Search

Logging, grazing, wood extraction, and anthropogenic fires are pervasive throughout the subtropical dry vegetation of South America leading to changes in woodlands structure and ultimately its degradation. The Chac ohaco biome encompasses the second-largest forest in South America and has a long history of intensive use. We sought to characterize the structure and heterogeneity of its woodlands across biogeo graphic subunits and climatic gradients, and evaluate structure controls. We quantified canopy height, cover, vertical complexity, vegetation amount above 3 m and total veg etation amount over 58 woodlands within the Argentinean Chaco by means of terres trial laser scanner. We assessed the relationship between three groups near the maximum, average and minimum values of each structural variable and precipitation, temperature and temperature of the coldest month using quantile regressions. We found large variability in structural attributes within each biogeographical subunit, showing woodland areas with similar structure across broad gradients of climate. This suggests a considerable impact of current and past land use in shaping woodland struc tures across the Chaco. Overall, structural variables were positively associated with precipitation and temperature, albeit more strongly to the former, except for canopy height, which showed a strong association with mean temperature of the coldest month. We hypothesize that land-use impact on woodland structure decreases with increasing precipitation, as the lack of water may limit the recovery of vegetation struc ture. Our results contribute to a better understanding of variation in key structural vari ables of Chaco woodlands in relation to climate and land use. Fil: Ferraina, Antonella. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Clima y Agua; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis. Grupo de Estudios Ambientales; Argentina. Universidad Nacional de San Luis; Argentina Fil: Abelleyra, D. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Clima y Agua; Argentina Fil: Grosfeld, Javier Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico y Tecnológico Patagonia Norte; Argentina. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina Fil: Verón, S. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Clima y Agua; Argentina

Soil is the most important terrestrial carbon (C) reservoir but is greatly impacted by land use change (LUC). Previous analyses of LUC impacts on soil C have focused on biophysical variables, leaving aside the influence of socioeconomics. The aim of our study was to determine global soil organic carbon (SOC) change patterns after LUC and to assess the impacts of both biophysical and socioeconomic factors that influence stocks of SOC after LUC simultaneously. This was done at a global scale using 817 sites from 99 peer-reviewed publications. We performed separate analyses for cases in which there were gains and losses of SOC. The best predictors of SOC stock changes were the type of LUC and predictors related to sampling depth, climate, biome, soil order, relief, geology, years since LUC, and primary productivity. However, also, socioeconomic variables such as indices of poverty, population growth, and levels of corruption were important. They explained 33% of the variability in SOC on their own and helped improve model accuracy from 42 to 53% when considered in combination with biophysical variables. SOC losses were highly correlated to the type of LUC and social variables, while SOC gains correlated most strongly with years since LUC and the biophysical variables. The analyses confirm that one of the biggest drivers of SOC loss is conversion to agroindustrial scale cropping, whereas with regard to the recuperation of SOC after LUC, the factor “time since conversion” emerged as the most important predictive variable, which must be better integrated in respective policy expectations. We conclude that policies should more than ever incentivize holistic approaches that prevent additional loss of native SOC, while at the same time promoting sustainable intensification of existing agricultural regions. Finally future investments on LUC to regain SOC should be aligned with efforts to alleviate poverty and corruption for their potential to achieve mutual gains in soil fertility and socio-economic parameters.

Pine tree invasions threaten many natural ecosystems of the Southern Hemisphere, modifying their structure and functioning through shifts in fire regimes, water balance, and biodiversity. The magnitude of such impacts depends on how much of the landscape has been invaded, thus a better understanding of the dispersal ability of pines and predictions of their future invasions are needed. Here we depict the spatio-temporal patterns of Pinus elliottii and Pinus taeda invading a new environment away from planted plots (i.e., invasion front), and discuss the underlying mechanisms that lead to a very concerning, yet poorly documented, pine invasion in central Argentina. Combining high-resolution imagery, allometric field data, and dendrochronology, we reconstructed the pine invasion into mountain grasslands from its onset in 1990. We found that even though the maximum density of invading pines (80 trees ha−1) was very low compared to adjacent plantation (1000 trees ha−1), density decreases exponentially with distance from the plantation edge. Remarkably, invading pines were found throughout the sampling plots showing high dispersal capacity, with no differences in age with increasing distance. The observed low density and spatially widespread exotic pine establishment, create a stealth type of invasion that is difficult to perceive in its early stages and challenging to manage once large areas are compromised. As invasion continues, long-distance dispersal will possibly become a major agent of landscape transformation and may lead to large pine-dominated neo-ecosystems, such as the savanna-like formation described here that replaced native grasslands in only three decades.

Over the last decades, the rapid replacement of native forests by crops and pastures in the Argentinean semiarid Chaco plains has triggered unprecedented groundwater level raises resulting from deep drainage increases, leading to the first massive waterlogging event on records (~25,000 Ha flooded in 2015 near Bandera, one of the most cultivated clusters of the Chaco). In this paper, we link this episode to the ongoing deforestation and cropping scheme shifts through the combined analysis of remote sensing data, agricultural surveys, local farmer information and hydrologic modelling. From 2000 to 2015, the agricultural area of Bandera increased from 21% to 50%, mostly at the expense of dry forests. In this period, agriculture migrated from more intensive (i.e., double-cropping) to more water-conservative (i.e., late-summer single crops) schemes as a general strategy to reduce drought risks. These changes reduced regional evapotranspiration and increased the intensity of deep drainage in wet years. Contrasting cropping schemes displayed significant evapotranspiration differences, but all of them experienced substantial drainage losses (~100–200 mm) during the wettest year (2014/2015), suggesting that cropping adjustments have a limited capacity to halt the generation of water excesses. Nearly 50% of the cropped area in Bandera could not be sown or harvested following the groundwater recharge event of 2014/2015. In the ongoing context of shallow and rising water tables, the introduction of novel cropping schemes that include deep-rooted perennials, to promote transpirative groundwater discharge, seems crucial to avoid the recurrence of water excesses and their associated dryland salinity risk in the region. Fil: Giménez, Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Mercau, Jorge Luis. Instituto Nacional de Tecnología Agropecuaria. Centro Regional La Pampa-San Luis. Estación Experimental Agropecuaria San Luis. Agencia de Extensión Rural San Luis; Argentina Fil: Bert, Federico Esteban. Universidad de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Kuppel, Sylvain. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Centre National de la Recherche Scientifique; Francia. University of Aberdeen; Reino Unido Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geología; Argentina Fil: Houspanossian, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geología; Argentina Fil: Magliano, Patricio Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; Argentina Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina

Aim: Invasive species have the potential to alter hydrological processes by changing the 7 local water balance. However, general patterns of how rainfall is partitioned into 8 interception, throughfall and stemflow for invasive species worldwide have been 9 seldom explored. We (a) describe the percentage of interception, throughfall and 10 stemflow for the invasive woody plant species; (b) analyse the influence of 11 morphological attributes (i.e., life-form, bark roughness, leaf type, leaf phenology and 12 leaf area index) of invasive species on rainfall partitioning; and (c) compare the rainfall 13 partitioning fluxes for co-occurring invasive and native species, testing whether these 14 fluxes variation depends on water availability of the study location. 15Location: Global. 16Time period: Present. 17Major taxa studied: Plants. 18Methods: We compiled data of 100 studies that assessed rainfall partitioning by 19 invasive species (N=67) and registered their morphological attributes. By means of a 20 meta-analysis we compared the rainfall partitioning by native and invasive species 21 (N=47 comparisons) and assessed how their fluxes were affected by water availability. 22Results: Interception, throughfall and stemflow ranged from 1.6 - 59.5%, 39.1 - 92.7% 23 and 0.1 - 31.6% of total rainfall, respectively. The bark roughness and leaf type were the 24 most important attributes driving rainfall partitioning fluxes. While rough-barked 25 species constrain rainfall inputs by promoting higher losses due to interception, smooth-26 barked species with broadleaves enhance the amount of rainwater reaching the soil by 27 maximizing stemflow. For pair-wise comparisons, invasive species have higher 28 stemflow values than native species for both drylands and humid areas, and higher 29 throughfall in drylands, but less in humid areas. 30Main conclusions: Our findings suggest that specific morphological attributes of 31 invasive species determine higher localized water inputs, which may represent an 32 ecohydrological advantage, particularly in water-limited ecosystems. These insights 33also suggest that the ecological role of stemflow, throughfall and interception should be 34 considered in future plant invasions research. 3536 Fil: Whitworth Hulse, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Magliano, Patricio Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; Argentina Fil: Zeballos, Sebastián Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Aguiar, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina

States are reacting to the global crises of biodiversity and the provision of ecosystem services mainly through the expansion of their networks of protected areas. This reaction would have been boosted by the commitments made between the parties of the Convention on Biological Diversity, and facilitated by the opportunities offered by isolated territories, where economic interests are minimal. However, few studies have discussed the importance of national power as conservation conditionings, particularly in the ocean. In this regard, here we evaluate whether the relative extent of marine protected areas (MPAs) is related to different elements of national power. Following a quantitative approach and incorporating into analyses 155 countries, our models suggest that an increasing power (in terms of country size –land and ocean– and military capacity) is related to greater marine protection. Although these patterns could be initially associated with the ample human and economic resources of most powerful countries and with the opportunities provided by their overseas territories, different arguments would support national power elements as conservation drivers. Specifically, the exertion of such power through conservation could be linked to geopolitical strategies such as the (re)validation of a country’s sovereignty over its Exclusive Economic Zone (EEZ), the greater regulation of the circulation and use of this space, the greater influence in the regional context, and the assurance in the provision of future ecosystem goods and services. In this way, changes in geopolitical conditions could affect MPAs, compromising the effective conservation of biodiversity and ecosystem processes, as well as the sustainable management of assets.

Protected areas are one of the most effective tools for nature conservation. Consequently, almost all countries have agreed to set increasingly demanding goals for the expansion of their protected area systems. However, there is a large disparity among countries, and research on the cultural drivers of differences remains quite unexplored. Here, we analyze the relationship between the protected extent and a limited spectrum of socio-economic characteristics, making focus on size and power features. Protected areas under strict conservation categories (I to IV, IUCN) were considered for 195 countries, and relationships were modeled by means of LOESS regressions, violin plots, and a random forest ensemble learning method. Larger and more powerful countries (in terms of land area, gross domestic product, or military expenditure) protect less and in relatively smaller units than smaller and less powerful countries. Out of the twenty most extensive countries of the world, only two exceed 10 % of protection. This situation is problematic since an effective growth of the global protected area network depends on the willingness of larger and more powerful countries. We propose different hypotheses a posteriori that explain the role of size and power driving protection. These hypotheses involve direct mechanisms (e.g., the persuasive capacity of large countries) or mechanisms that mediate the interactions of some others (e.g., tourism contribution to GDP and insularity). Independently of mechanisms, our results emphasize the conservation responsibilities of large and powerful countries and contribute envisioning conservation scenarios in the face of changes in the number and size of countries. Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina

Fil: Baldi, Germán. Universidad Nacional de San Luis. Instituto de Matemática Aplicada San Luis. San Luis, Argentina. Fil: Schauman, Santiago. Universidad Nacional de San Luis. Instituto de Matemática Aplicada San Luis. San Luis, Argentina. Fil: Texeira, Marcos. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Métodos Cuantitativos y Sistemas de Información. Buenos Aires, Argentina. Fil: Marinaro, Sofía. Universidad Nacional de Tucumán. Instituto de Ecología Regional. - CONICET - Horco Molle, Horco Molle, Tucumán Fil: Martin, Osvaldo A. Universidad Nacional de San Luis. Instituto de Matemática Aplicada San Luis. San Luis, Argentina. Fil: Gandini, Patricia. Universidad Nacional de la Patagonia Austral. Instituto Ciencias del Ambiente, Sustentabilidad y Recursos Naturales. Santa Cruz, Argentina. Fil: Jobbágy, Esteban G. Universidad Nacional de San Luis. Instituto de Matemática Aplicada San Luis. San Luis, Argentina. Background: South America faces strong environmental transformations due to agriculture and infrastructure expansion and due to demographic growth, demanding immediate action to preserve natural assets by means of the deployment of protected areas.\nCurrently, 7.1% of the (sub)continent is under strict conservation categories (I to IV, IUCN), but the spatial distribution of these 1.3 x 106 km2 is poorly understood.\nWe evaluate protected area representativeness, map conservation priorities and assess demographic, productive or geopolitical causes of the existing protection spatial patterns using a random forest method.\nMethods: We characterized representativeness by two dimensions: the extent and the equality of protection.\nThe first refers to the fraction of a territory under protection, while the second refers to the spatial distribution of this protection along natural conditions.\nWe characterized natural conditions by 113 biogeographical units (specifically, ecoregions) and a series of limited and significant climatic, topographic and edaphic traits.\nWe analyzed representativeness every ten years since 1960 at national and continental levels. In the physical approach, histograms allowed us to map the degree of conservation priorities.\nFinally, we ranked the importance of different productive or geopolitical variables driving the observed distributions with a random forest technique.\nResults: Representativeness was variable across countries in spite of its priority in conservation agendas.\nBrazil, Peru and Argentina underrepresented a significant fraction of their natural diversity, while Bolivia and Venezuela protected their natural diversity equitably under extensive conservation networks.\nAs protected networks increased their extent, so did their equality across countries and within them through time.\nMapping revealed as top continental priorities southern temperate, subhumid and fertile lowland environments, and other country - specific needs (e.g., hot, humid plains of Venezuela). Protection extent was generally driven by a low population density and isolation, while other variables - like distance to frontiers, were relevant only locally (e.g., in Argentina). Discussion: Our description of the spatial distribution can help societies and governments to improve the allocation of conservation efforts, being top continental priorities the southern temperate, subhumid and fertile lowland environments.\nWe identify the main limitations that future conservation efforts will face, as protection was generally driven by the opportunities provided by low population density and isolation.\nFrom a methodological perspective, the complementary physical approach reveals new properties of protection and provides tools to explore nature representativeness at different spatial, temporal and conceptual levels, complementing the traditional ones based on biodiversity or biogeographical attributes. grafs., tbls., mapas

Sustainability science recognizes the importance of the integrated assessment of the ecological and social systems in land-use planning. However, most studies so far have been conceptual rather than empirical. We developed a framework to characterize the social-ecological systems heterogeneity according to its functioning through the identification of social–ecological functional types (SEFT). The SEFT framework builds on the plant, ecosystem and agent functional type approaches, taking a step forward to integrate the dimensions of social–ecological systems into an operational product to characterize administrative units in a hierarchical way. To illustrate this novel framework, we described the heterogeneity of SEFT in the Argentine Chaco by clustering administrative entities. This area is a global deforestation hotspot and has diverse social actors that harness ecosystem services in multiple, and sometimes contrasting and conflictive, ways which determines an urgent need for land-use planning. We combined data from national census and remote sensing to identify SEFT by clustering census tracts based on 17 input variables that integrate key human, ecological and interaction processes across landscapes. We identified three classes and eight subclasses of SEFT. Ecological variables defined the first level of heterogeneity (classes), while human variables and the variables of interactions between the human and ecological components defined a second level of heterogeneity (subclasses). The degree of anthropization and mean annual productivity were important variables to explain the first two axes in the ordination (32% of the total variance). This framework offers a conceptually novel and comprehensive approach to understand the spatial heterogeneity of social–ecological systems functioning, which could play a pivotal role to support conservation or land-use planning in rural areas. Fil: Vallejos, María. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Aguiar, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Mastrangelo, Matias Enrique. Universidad Nacional de Mar del Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Gallego, Federico. Universidad de la República; Uruguay Fil: Pacheco Romero, Manuel. Universidad de Almería; España Fil: Alcaraz Segura, Domingo. Universidad de Almería; España. Universidad de Granada; España Fil: Paruelo, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Universidad de la República; Uruguay

The replacement of natural vegetation by pastures and extensive crops is generally driven by economic incentives and supported by technology improvements and multiple subsidies. However, towards areas of increasing aridity the productive performance of these replacements may decline from all perspectives – ecological to agronomic to economic – due to intrinsic differences in the structural and physiological adjustment of natural and cultivated vegetation to reduced and fluctuating water availability. We compare natural woody vegetation, perennial C4 pastures and annual crops (maize, soybean and wheat) along a gradient of decreasing precipitation (900–400 mm of annual mean) encompassing the current agricultural frontier of the Dry Chaco and Western Espinal ecoregions of South America. We assess (i) aboveground net primary productivity (ANPP) (ii) yields of product dry mass, edible energy and protein outputs and, (iii) economic gross profits and return of investment. We linked climatic with yield data from national statistics, field trials and empiric models, together with productive parameters and market prices obtained from local consultants and economic bulletins. Maize achieved the highest ANPP of all vegetation covers (+ 42% in average compared to the rest) along the entire precipitation gradient, while the rest of the crops were very similar to natural vegetation. Pastures approached the ANPP of natural vegetation in the humid range, but had the lowest performance below 700 mm (− 15%). Along the entire precipitation gradient, maize was outstanding in mass and edible energy yield while soybean was so in protein production. Soybean had the highest gross profit per hectare (+ 50%) and total capital return of investment (+ 70%). Pastures offered the highest functional capital return of investment (+ 98%; without fixed capital, infrastructure and land value costs), explaining their relevance at the onset of the deforestation process and the gradual prevalence of crops afterwards. While agronomic and economic incentives for natural vegetation replacement remain strong along the whole aridity gradient, crop choice rather than land use system seem to shape the key ecological process of net primary productivity. Fil: Murray, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional La Pampa-San Luis; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: von Bernard, Tamara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Viglizzo, Ernesto Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Industrial. Centro Regional La Pampa; Argentina Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina

The net amount of rainfall entering into the soil and its spatial distribution at the patch scale are key drivers of ecosystem processes in drylands. The spatial distribution of water is mainly controlled by vegetation canopy which determines the partitioning of rainfall into interception, throughfall and stemflow. In this paper, we synthesized and analyzed rainfall partitioning for 68 woody plant species in drylands (delimited by a rainfall-potential evapotranspiration ratio 0.05 for all cases). Shrubs were more abundant towards the dry edge of the rainfall gradient (145-500 mm year^−1), while trees were more abundant towards the subhumid edge (500-805 mm year^−1). These results suggested that higher stemflow found towards the dry edge of the rainfall gradient was caused by the higher abundance of shrubs, which generated more stemflow than trees. Our findings highlighted the ecohydrological key role of vegetation life form and rainfall inputs affecting the amount of water entering into the soil and its spatial distribution in drylands. Fil: Magliano, Patricio Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia; Argentina Fil: Whitworth Hulse, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina

The Dry Chaco is mostly known as a forested ecosystem. However it includes natural grasslands, savannas, scrublands, and wetlands. With one of the highest global deforestation rates in the last two decades and only 12% of the area protected, the concern about land-use change in this ecoregion has raised exponentially; but conservation initiatives developed in last years almost exclusively targeted forests whereas natural grasslands and savannas remain as neglected ecosystem within scientific and governmental agendas. While currently the distribution of natural grassland and savanna area encompasses over 20,000 km2, historical records and spatial models indicate that natural grassland and savannas were more widespread in pre-European era. Two main reasons drove this reduction in natural grasslands and savannas: woody encroachment by fire suppression and overgrazing, and conversion to agriculture and implanted pastures. In this article, through a combination of analyzes and bibliographic revisions, we describe biotic and abiotic components of natural grassland and savannas of the Dry Chaco. We also present the current distribution and conservation status of these ecosystems, and describe the process of change and the ecological consequences for biogeochemical cycles and biologic interactions. To provide basis for management, we estimate current grazing stocking rates on natural grasslands and savannas of Argentine Dry Chaco and we propose an alternative approach to sustainably intensify the use of these ecosystems and improve cattle rancher livelihoods. Despite the existent knowledge about natural grasslands and savannas in the region, we believe that is necessary to motivate the scientific community and national institutions to increase efforts to reconcile the restoration and conservation of these particular rangelands. Fil: Fernández, Pedro. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Investigación Animal del Chaco Semiárido; Argentina Fil: Baumann, Mathias. Humboldt-Universität zu Berlin; Alemania Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Banegas, Natalia Romina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Investigación Animal del Chaco Semiárido; Argentina Fil: Bravo, Sandra. Universidad Nacional de Santiago del Estero. Facultad de Ciencias Forestales. Instituto de Silvicultura y Manejo de Bosques; Argentina Fil: Gasparri, Nestor Ignacio. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentina Fil: Lucherini, Mauro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; Argentina Fil: Marinaro Fuentes, María Sofía. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentina Fil: Nanni, Ana Sofía. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentina Fil: Nasca, Jose Andres. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias. Instituto de Investigación Animal del Chaco Semiárido; Argentina Fil: Tessi, Torcuato. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Córdoba. Estación Experimental Agropecuaria Manfredi; Argentina Fil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentina

El vasto territorio del Chaco Seco y el Espinal se consolida como uno de los centros globales de producción de granos y carne. Tanto por distintas normas legales, limitaciones productivas, o causas culturales, el bosque nativo se preserva en grandes porciones y numerosos pequeños fragmentos inmersos en la matriz agrícola (en lo subsiguiente, "remanentes"). Estos remanentes suelen pasar desapercibidos para la comunidad científica y los tomadores de decisiones, quedando al margen de la planificación territorial y de acciones de conservación. En este trabajo describimos la estructura espacial de los remanentes, y generamos un esquema de clasificación que permite identificar distintos tipos según sus propiedades espaciales. Siguiendo una estrategia de clasificación basada en objetos, cartografiamos ~22,000 remanentes en ocho áreas focales (AF) dispersas en el territorio usando imágenes satelitales CBERS-2B. Mediante índices espaciales, estos remanentes de tamaños, formas, y niveles de aislamiento variables, fueron categorizados en cinco clases, desde "isletas" hasta "bloques compactos". La superficie de remanentes resultó mayor en el Chaco Seco que en el Espinal (entre 10.1% y 19.4% en la primera región, y entre 3.1% y 7.3% en la segunda). Las diferencias en el nivel de fragmentación se amplificaron entre AF, dependiendo tanto de la superficie total de remanentes, como de la ocurrencia relativa de distintos tipos. Así, en AF San Luis la fragmentación resultó 70 superior que en AF de Anta (Salta). En este trabajo brindamos herramientas para la identificación y el monitoreo de estos remanentes, las cuales podrán ser consideradas tanto con fines productivos como de conservación. Finalmente, las acciones de manejo y conservación deben reconocer la existencia de estos fragmentos de bosques en paisajes altamente transformados por la actividad agropecuaria. The vast territory of the Dry Chaco and the Espinal became one of the global centers for the production of grains and meat. Due to different legal norms, productive limitations or cultural causes, the native forest is preserved on extensive patches as well as on numerous small fragments within the agricultural matrix. These remnants are seldom considered by the scientific community and decision-makers, and are left out of territorial planning and conservation actions. In this paper, we describe the spatial structure of the remnants and generate a classification scheme that allows identifying different types according to their spatial properties. Following an object-based classification strategy, we mapped ~22000 remnants in eight foci areas (FA) scattered throughout the territory using CBERS-2B satellite images. By means of spatial metrics, these remnants of variable sizes, shapes and isolation levels were categorized into five classes, from “islets” to “compact blocks”. The surface of remnants was higher in the Dry Chaco than in the Espinal (between 10.1% and 19.4% in the first region, and between 3.1% and 7.3% in the second). Differences in the level of fragmentation were amplified between FA, depending both on the total surface of remnants and on the relative occurrence of different types. Thus, in the FA of San Luis the fragmentation was 70 times higher than in the FA of Anta (Salta). In this work, we provide tools for the identification and monitoring of these remnants, which may be considered for both productive and conservation purposes. Finally, management and conservation actions must recognize the existence of these pieces of forest in landscapes highly transformed by agricultural activity. Fil: Muñoz Garachana, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Aragón, Myriam Roxana. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina

In the South American dry forest of the Dry Chaco and Chiquitania, the area under cultivation rose from 10% to 19% over the last ten years, and little biophysical, economical, or political constrains seem to prevent further expansion. Although typically associated to a homogeneous agribusiness system, agriculture and its expansion in this territory involve a diverse array of land users. Here we (i) identified and mapped the most conspicuous groups of land users based on existing scientific literature and technical reports, and (ii) described their associated landscape pattern and (iii) vegetation functioning based on different remote sensing tools applied to a set of 218 sample points. We recognized 14 groups of land users of local or foreign origin, composed by individuals or corporative organizations, and dedicated to farming, ranching or both. These groups displayed a wide variation in the scale of their operations as suggested by a 60-fold difference in paddock sizes. Twelve years of MODIS-NDVI data showed small and non- significant differences in the magnitude of primary productivity (1.2 fold-difference) but strong contrasts in its seasonality and long-term variability, including shifts in the rates of vegetation greening and browning (up to 4 fold-differences), growing period length (193 to 278 days y-1)number of cultivation seasons per year (1 to 1.75), and inter-annual coefficient of variation (up to 0.13). Agriculture under capitalized groups was characterized by very large paddocks, less stable productivity patterns, and more divergent seasonality. Instead, all smallholders showed more stable productivities both seasonally and inter-annually. Deforestation and cultivation in these dry regions does not have a single imprint on landscapes configuration and primary production dynamics, but one that shifts depending on the human and productive context under which they take place. Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina Fil: Houspanossian, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina Fil: Murray, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Rosales, Adriel A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina. Universidad de La Punta; Argentina Fil: Rueda, Carla Vanezza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina. Universidad Nacional de Santiago del Estero. Facultad de Ciencias Forestales. Instituto de Silvicultura y Manejo de Bosques; Argentina Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina

Charcoal production has been widespread in the past and is still common where poor societies and dry forests coexist. For the Dry Chaco in South America, one of the largest remaining dry forests of the world, we describe the geographical distribution, type of production systems, environmental and social context and output of charcoal based on remote sensing (charcoal kiln detection); together with existing environmental (forest cover/biomass), social (population density, poverty), and infrastructure (roads) data. While most of the region has low kiln densities (1 kiln every 5km2). Individual or small groups (up to three units) prevail over the regions (58.2% of all kiln sites), frequently associated with a forest land cover. Large groups of kilns (≥12 units, 15.5% of all kilns) were associated with land cleared for cultivation. For a subset of kiln sites for which forest biomass data was available, we found that typical kiln sites (1-3 kilns) had half of the average biomass of the region within a radius of 125m. Although charcoal production in the whole region has been stable for 50years, a strong redistribution from richer to poorer provinces has taken place. At the county level, kiln density and charcoal production records showed a linear association that suggests an average output of 11 tons of charcoal per year per kiln. Comparing counties with high vs. low charcoal production with similarly high forest cover, the first had higher population density and poverty levels. Today small scale charcoal production by poor rural people represents the only significant use of forests products that provides some market incentive for their preservation. However this situation is associated with marginal social conditions, inefficient production, and forest degradation. Developing charcoal production under environmentally and socially virtuous conditions should be seen as a unique opportunity and an urgent challenge in the face of the fast deforestation of dry forests. Fil: Rueda, Carla Vanezza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis; Argentina. Universidad Nacional de San Luis; Argentina. Universidad Nacional de Santiago del Estero. Facultad de Cs.forestales. Instituto de Silvicultura y Manejo de Bosques; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis; Argentina. Universidad Nacional de San Luis; Argentina Fil: Gasparri, Nestor Ignacio. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis; Argentina. Universidad Nacional de San Luis; Argentina

Tropical and Subtropical dry forests around the globe are experiencing rapid clearing and concomitant biodiversity loss (1). In their Research Article "Plantdiversity patterns in neotropical dry forests and their conservation implications" (23 September 2016, p. 1383), DRYFLOR et al. highlight the often underappreciated, yet exceptional floristic richness and uniqueness of these forests, and they provide compelling arguments for ramping up efforts to protect them. We applaud the DRYFLOR team for their seminal work, but we are also concerned about the exclusion of the Gran Chaco, frequently considered the world's largest continuous tropical dry forest region. Fil: Kuemmerle, Tobias. Humboldt-University Berlin. Geography Department; Alemania Fil: Altrichter, Mariana. Prescott College. Department of Environmental Studies; Estados Unidos Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina Fil: Cabido, Marcelo Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Camino, Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Cuellar, Erika. Santa Cruz; Bolivia Fil: Cuellar, Rosa Leny. Fundación Kaa Iya; Bolivia Fil: Decarre, Julieta. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias; Argentina Fil: Díaz, Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Gasparri, Nestor Ignacio. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Laboratorio de Investigaciones Ecológicas de las Yungas; Argentina Fil: Gavier Pizarro, Gregorio. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigaciones Agropecuarias; Argentina Fil: Ginzburg, Rubén Gabriel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina Fil: Giordano, Anthony J.. Society for the Preservation of Endangered Carnivores and their International Ecological Study; Estados Unidos. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Laboratorio de Investigaciones Ecológicas de las Yungas; Argentina Fil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Laboratorio de Investigaciones Ecológicas de las Yungas; Argentina Fil: Jobbagy Gampel, Esteban Gabrie. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina Fil: Leynaud, Gerardo Cristhian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentina Fil: Macchi, Leandro. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Laboratorio de Investigaciones Ecológicas de las Yungas; Argentina Fil: Mastrangelo, Matias Enrique. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias. Laboratorio de Agroecología; Argentina Fil: Matteucci, Silvia Diana. Universidad de Buenos Aires. Facultad de Arquitectura y Urbanismo. Grupo de Ecología del Paisaje y Medio Ambiente; Argentina Fil: Noss, Andrew. University of Florida; Estados Unidos Fil: Paruelo, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Piquer Rodríguez, Maria. Humboldt-University Berlin. Geography Department; Alemania Fil: Romero Muñoz, Alfredo. Humboldt-University Berlin. Geography Department; Alemania Fil: Semper-Pascual, Asunción. Humboldt-University Berlin. Geography Department; Alemania Fil: Thompson, Jeffrey J.. Guyra Paraguay; Paraguay. Consejo Nacional de Ciencia y Tecnología; Paraguay Fil: Torrella, Sebastián Andrés. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina Fil: Torres, Ricardo Marcelo. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Museo de Zoología; Argentina Fil: Volante, José Norberto. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Salta-Jujuy. Estación Experimental Agropecuaria Salta; Argentina Fil: Yanosky, Alberto. Guayra Paraguay; Paraguay Fil: Zak, Marcelo Román. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina

Few field studies examine greenhouse gas (GHG) emissions from African agricultural systems, resulting in high uncertainty for national inventories. This lack of data is particularly noticeable in smallholder farms in sub-Saharan Africa, where low inputs are often correlated with low yields, often resulting in food insecurity as well. We provide the most comprehensive study in Africa to date, examining annual soil CO2, CH4 and N2O emissions from 59 smallholder plots across different vegetation types, field types and land classes in western Kenya. The study area consists of a lowland area (approximately 1200ma.s.l.) rising approximately 600m to a highland plateau. Cumulative annual fluxes ranged from2.8 to 15.0MgCO2-Cha-1,-6.0 to 2.4kgCH4-Cha-1 and-0.1 to 1.8kgN2O-Nha-1. Management intensity of the plots did not result in differences in annual GHG fluxes measured (P Combining double low line 0.46, 0.14 and 0.67 for CO2, CH4 and N2O respectively). The similar emissions were likely related to low fertilizer input rates (≤20kgNha-1). Grazing plots had the highest CO2 fluxes (P Combining double low line 0.005), treed plots (plantations) were a larger CH4 sink than grazing plots (P Combining double low line 0.05), while soil N2O emissions were similar across vegetation types (P Combining double low line 0.59). This study is likely representative for low fertilizer input, smallholder systems across sub-Saharan Africa, providing critical data for estimating regional or continental GHG inventories. Low crop yields, likely due to low fertilization inputs, resulted in high (up to 67gN2O-Nkg-1 aboveground N uptake) yield-scaled emissions. Improvement of crop production through better water and nutrient management might therefore be an important tool in increasing food security in the region while reducing the climate footprint per unit of food produced. Fil: Pelster, David. International Livestock Research Institute; Kenia Fil: Rufino, Mariana Cristina. Centre for International Forestry Research; Kenia. Lancaster University; Reino Unido Fil: Rosenstock, Todd. World Agroforestry Centre; Kenia Fil: Mango, Joash. World Agroforestry Centre; Kenia Fil: Saiz, Gustavo. Karlsruhe Institute of Technology; Alemania Fil: Diaz Pines, Eugenio. Karlsruhe Institute of Technology; Alemania Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Butterbach Bahl, Klaus. International Livestock Research Institute; Kenia. Karlsruhe Institute of Technology; Alemania

The aim of this work was to determine Echinococcus granulosus sensu lato species and genotypes in intermediate and definitive hosts and in human isolates from endemic regions of Argentina and Brazil including those where no molecular data is available by a combination of classical and alternative molecular tools. A total of 227 samples were isolated from humans, natural intermediate and definitive hosts. Amplification of cytochrome c oxidase subunit I gene fragment was performed and a combination of AluI digestion assay, High Resolution Melting anal- ysis (HRM) assay and DNA sequencing was implemented for Echinococcus species/genotype determination. E. granulosus sensu stricto (G1) was found in sheep (n = 35), cattle (n = 67) and dogs (n = 5); E. ortleppi (G5) in humans (n = 3) and cattle (n = 108); E. canadensis (G6) in humans (n = 2) and E. canadensis (G7) in pigs (n = 7). We reported for the first time the presence of E. ortleppi (G5) and E. canadensis (G6) in humans from San Juan and Catamarca Argentinean provinces and E. canadensis (G7) in pigs from Cordoba Argentinean province. In this work, we widened molecular epidemiology studies of E. granulosus s. l. in South America by an- alyzing several isolates from definitive and intermediate hosts, including humans from endemic regions were such information was scarce or unavailable. The presence of different species/genotypes in the same region and host species reinforce the need of rapid and specific techniques for accurate determination of Echinococcus species such as the ones proposed in this work. Fil: Avila, Héctor Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina. Centro de Investigaciones en Zoonosis; Argentina Fil: Santos, Guilherme B.. Universidade Federal do Rio Grande do Sul; Brasil Fil: Cucher, Marcela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Macchiaroli, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Pérez, Matías Gastón. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis; Argentina Fil: Jensen, Oscar. Centro de Investigaciones en Zoonosis; Argentina Fil: Pérez, Matías Gastón. División Zoonosis; Argentina Fil: López, Raúl. Departamento de Zoonosis Provincial; Argentina Fil: Negro, Perla Susana. Cátedra de Parasitología y Enfermedades Parasitarias; Argentina Fil: Scialfa, Exequiel Alejandro. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Agronomía; Argentina Fil: Zaha, Arnaldo. Universidade Federal do Rio Grande do Sul; Brasil Fil: Ferreira, Henrique B.. Universidade Federal do Rio Grande do Sul; Brasil Fil: Rosenzvit, Mara Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina Fil: Kamenetzky, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; Argentina

In this paper, we explored how aridity influences the regional deforestation and land-use patterns (i.e. crops/pastures) in South American Dry Chaco. To do this, we contrasted land use during last decade (2001–2012) with a spatially explicit aridity index, which we complemented with a crop water balance model. Land-use classifications were performed by considering the temporal variability of NDVI from MODIS satellites, showing that 40 and 60% of deforested land was assigned to crops and pastures, respectively. Results indicate that although the regional deforestation pattern was not associated with the aridity gradient, with drier areas similarly deforested as wetter areas, contrasting differences were observed in the use of this land, with crops mostly located (90%) in wetter areas and pastures evenly distributed across the whole aridity gradient. This research highlighted the strong effect of water limitations on the land-use option after deforestation and may help to set the basis for future land-use planning policies. Fil: Houspanossian, Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina Fil: Giménez, Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina Fil: Nosetto, Marcelo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis ; Argentina

The lack of long-term records of productivity is a critical limitation to the study of ecosystem dynamics. Annual rings, a measure of growth in woody species, are a useful tool to document ecosystem dynamics. Time series of the Normalized Difference Vegetation Index (NDVI) provide estimates of ecosystem productivity through satellite-derived data on the fraction of photosynthetic active radiation absorbed by vegetation. In the Patagonian steppes, we relate changes in NDVI to interannual variations in the radial growth of the shrub Anarthrophyllum rigidum. A widely distributed network of 15 ring-width chronologies of A. rigidum was used to estimate changes in NDVI across the Patagonia steppe (35°–50°S). In most sites, interannual variations in shrub growth and NDVI are regulated by winter precipitation. The water accumulated in the soil during winter is used by A. rigidum during the growing season, concurrent with the maximum NDVI values. At 10 from the 15 selected sites, variations in the radial growth of A. rigidum explained between 23 and 62% of the total variance in seasonal NDVI, suggesting that the A. rigidum growth at some sites provides good estimates of productivity in the Patagonian shrubby steppes during the growing season. However, we were unable to determine clear relationships between radial growth and NDVI at high-elevation mountainous sites or where intensive grazing by sheep masked the effect of climate variability on shrub growth. We conclude that dendrochronological methods can complement other estimates to reconstruct variations of productivity, supplementing and extending the few short records available in the Patagonian steppe.

Grasslands are one of the most modified biomes on Earth. Land use changes had a large impact on carbon (C) stocks of grasslands. Understanding the impact of land use/land cover changes on C stocks and fluxes is critical to evaluate the potential of rangeland ecosystem as C sinks. In this article we analyze C stocks and fluxes across the environmental gradients of one of the most extensive temperate rangeland areas: the Rio de la Plata Grasslands (RPG) in South America. The analysis summarizes information provided by field studies, remote sensing estimates, and modeling exercises. Average estimates of aboveground net primary production (ANPP) ranged from 240 to 316 g C ? m 22 ? yr 21 . Estimates of belowground NPP (BNPP) were more variable than ANPP and ranged from 264 to 568 g C ? m 22 ? yr 21 . Total Carbon ranged from 5 004 to 15 008 g C ? m 22 . Plant biomass contribution to Total Carbon averaged 13% and varied from 9.5% to 27% among sites. The largest plant C stock corresponded to belowground biomass. Aboveground green biomass represented less than 7% of the plant C. Soil organic carbon (SOC) was concentrated in the slow and passive compartments of the organic matter. Active soil pool represented only 6.7% of the SOC. The understanding of C dynamics and stocks in the RPG grasslands is still partial and incomplete. Field estimates of ANPP and BNPP are scarce, and they are not based on a common measurement protocol. Remotely sensed techniques have the potential to generate a coherent and spatially explicit database on ANPP. However, more work is needed to improve estimates of the spatial and temporal variability of radiation use efficiency. The absence of a flux tower network restricts the ability to track seasonal changes in C uptake and to understand fine-scale controls of C dynamics. Resumen

This chapter presents a method for targeting landscapes with the objective of assessing mitigation options for smallholder agriculture. It presents alternatives in terms of the degree of detail and complexity of the analysis, to match the requirement of research and development initiatives. We address heterogeneity in land-use decisions that is linked to the agro-ecological characteristics of the landscape and to the social and economic profiles of the land users. We believe that as projects implement this approach, and more data become available, the method will be refined to reduce costs and increase the efficiency and effectiveness of mitigation in smallholder agriculture. The approach is based on the assumption that landscape classifications reflect differences in land productivity and greenhouse gas (GHG) emissions, and can be used to scale up point or field-level measurements. At local level, the diversity of soils and land management can be meaningfully summarized using a suitable typology. Field types reflecting small-scale fertility gradients are correlated to land quality, land productivity and quite likely to GHG emissions. A typology can be a useful tool to connect farmers? fields to landscape units because it represents the inherent quality of the land and human-induced changes, and connects the landscape to the existing socioeconomic profiles of smallholders. The method is explained using a smallholder system from western Kenya as an example. Fil: Rufino, Mariana Cristina. Centre for International Forestry Research Institute; Kenia Fil: Atzberger, Clement. University of Natural Resources; Austria Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Butterbach Bahl, Klaus. International Livestock Research Institute; Kenia Fil: Rosenstock, Todd S.. World Agroforestry Centre; Kenia Fil: Stern, David. Maseno University; Kenia

The dry subtropics are subject to a rapid expansion of crops and pastures over vast areas of natural woodlands and savannas. In this paper, we explored the effect of this transformation on vegetation productivity (magnitude, and seasonal and long-term variability) along aridity gradients which span from semiarid to subhumid conditions, considering exclusively those areas with summer rains (>66%). Vegetation productivity was characterized with the proxy metric "Enhanced Vegetation Index" (EVI) (2000 to 2012 period), on 6186 natural and cultivated sampling points on five continents, and combined with a global climatology database by means of additive models for quantile regressions. Globally and regionally, cultivation amplified the seasonal and inter-annual variability of EVI without affecting its magnitude. Natural and cultivated systems maintained a similar and continuous increase of EVI with increasing water availability, yet achieved through contrasting ways. In natural systems, the productivity peak and the growing season length displayed concurrent steady increases with water availability, while in cultivated systems the productivity peak increased from semiarid to dry-subhumid conditions, and stabilized thereafter giving place to an increase in the growing season length towards wetter conditions. Our results help to understand and predict the ecological impacts of deforestation on vegetation productivity, a key ecosystem process linked to a broad range of services. Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Texeira González, Marcos Alexis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Murray, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina

Rainwater harvesting (RWH) has been essential for the establishment of human settlements in many dry regions of the world that lacked suitable surface or groundwater resources. A vast fraction of the South American Dry Chaco ecoregion still relies on RWH to support, not only livestock production, but domestic and industrial uses as well. As a result, water capture and storage infrastructure is widely disseminated throughout the region. In this paper we characterized the most typical RWH systems in two contrastingly developed sub-regions of Dry Chaco, ranging from extensive ranching to intensive beef and dairy production (central Argentina and western Paraguay, respectively). In each sub-region, we quantified RWH systems density, spatial distribution and associations with landscape features; furthermore, we illustrated how the daily dynamic of water stock in a typical RWH system contributes to assess their capture and storage efficiency. We found that randomly distributed low sophisticated RWH systems prevailed in central Argentina, while clustered distributed high sophisticated ones were more common in western Paraguay. RWH systems density was ten times higher in western Paraguay (0.94 vs. 0.098 units/km2), showing an exponential association with land cleared fraction and proximity to villages. The daily dynamic of water stock of the RWH impoundment showed that water harvest events were exponentially associated with precipitation magnitude events (R2 = 0.86), while annual water losses were explained by infiltration and evaporation fluxes (59 vs. 41%, respectively). Across both sub-regions, RWH accounts for less than 1% of the annual precipitation, playing a minor role on the regional water balance; however at a local level, they can affect several hydrological fluxes including the onset of groundwater recharge and the mitigation of extreme runoff events. Fil: Magliano, Patricio Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis; Argentina Fil: Murray, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis; Argentina. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis; Argentina Fil: Aurand, Santiago. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Paez, Ricardo Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis; Argentina Fil: Harder, Wilbert. Servicio Agropecuario Paraguayo; Paraguay Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis; Argentina

To systematically review publications on Echinococcus granulosus sensu lato species/genotypes reported in domestic intermediate and definitive hosts in South America and in human cases worldwide, taking into account those articles where DNA sequencing was performed; and to analyse the density of each type of livestock that can act as intermediate host, and features of medical importance such as cyst organ location.Literature search in numerous databases. We included only articles where samples were genotyped by sequencing since to date it is the most accurate method to unambiguously identify all E. granulosus s. l. genotypes. Also, we report new E. granulosus s. l. samples from Argentina and Uruguay analysed by sequencing of cox1 gene.In South America, five countries have cystic echinococcosis cases for which sequencing data are available: Argentina, Brazil, Chile, Peru and Uruguay, adding up 1534 cases. E. granulosus s. s. (G1) accounts for most of the global burden of human and livestock cases. Also, E. canadensis (G6) plays a significant role in human cystic echinococcosis. Likewise, worldwide analysis of human cases showed that 72.9% are caused by E. granulosus s. s. (G1) and 12.2% and 9.6% by E. canadensis G6 and G7, respectively.E. granulosus s. s. (G1) accounts for most of the global burden followed by E. canadensis (G6 and G7) in South America and worldwide. This information should be taken into account to suit local cystic echinococcosis control and prevention programmes according to each molecular epidemiological situation.

Few field studies examine greenhouse gas (GHG) emissions from African agricultural systems resulting in high uncertainty for national inventories. We provide here the most comprehensive study in Africa to date, examining annual CO2, CH4 and N2O emissions from 59 plots, across different vegetation types, field types and land classes in western Kenya. The study area consists of a lowland area (approximately 1200 m a.s.l.) rising approximately 600 m to a highland plateau. Cumulative annual fluxes ranged from 2.8 to 15.0 Mg CO2-C ha−1, −6.0 to 2.4 kg CH4-C ha−1 and −0.1 to 1.8 kg N2O-N ha−1. Management intensity of the plots did not result in differences in annual fluxes for the GHGs measured (P = 0.46, 0.67 and 0.14 for CO2, N2O and CH4 respectively). The similar emissions were likely related to low fertilizer input rates (≤ 20 kg ha−1). Grazing plots had the highest CO2 fluxes (P = 0.005); treed plots were a larger CH4 sink than grazing plots (P = 0.05); while N2O emissions were similar across vegetation types (P = 0.59). This case study is likely representative for low fertilizer input, smallholder systems across sub-Saharan Africa, providing critical data for estimating regional or continental GHG inventories. Low crop yields, likely due to low inputs, resulted in high (up to 67 g N2O-N kg−1 aboveground N uptake) yield-scaled emissions. Improving crop production through intensification of agricultural production (i.e. water and nutrient management) may be an important tool to mitigate the impact of African agriculture on climate change.

Land use and land cover change (LUCC) affects regional climate through modifications in the water balance and energy budget. These impacts are frequently expressed by: changes in the amount and frequency of precipitation and alteration of surface temperatures. In South America, most of the studies of the effects of LUCC on the local and regional climate have focused on the Amazon region (54 studies), whereas LUCC within non-Amazonian regions have been largely undermined regardless their potential importance in regulating the regional climate (19 studies). We estimated that 3.6million km^2 of the original natural vegetation cover in non-Amazonian South America were converted into other types of land use, which is about 4 times greater than the historical Amazon deforestation. Moreover, there is evidence showing that LUCC within such fairly neglected ecosystems cause significant reductions in precipitation and increases in surface temperatures, with occasional impacts affecting neighboring or remote areas. We explore the implications of these findings in the context of water security, climatic extremes and future research priorities. Fil: Salazar, Alvaro. The University of Queensland; Australia Fil: Baldi, Germán. Universidad Nacional de San Martín. Instituto de Investigaciones en Ingeniería Ambiental. Centro de Estudios Ambientales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Hirota, Marina. Universidade Federal de Santa Catarina; Brasil Fil: Syktus, Jozef. The University of Queensland; Australia Fil: McAlpine, Clive. The University of Queensland; Australia

In the last century, the grasslands of southern South America were rapidly converted to croplands, starting a fragmentation process that is still ongoing. Almost no information is available on the spatial patterns and environmental controls of these processes. Our objective was to characterize the degree of fragmentation and to analyze the environmental controls of landscape composition of the Rio de la Plata grasslands, in southern South America. We classified land cover types using three Landsat TM scenes and we analyzed landscape structure using six metrics. Grassland is still the predominant land cover type in the Pampas, occupying 65.5% of the analyzed area. The abundance of the original land cover varied regionally, being higher in the south east (Flooding Pampa) and lower in the northern part of the area studied (Rolling Pampa). Landscape fragmentation was determined by crop production, therefore, was highest in the Rolling Pampa and lowest in the Flooding Pampa. The fragmentation patterns were associated to both climatic and edaphic factors. Fragmentation of native vegetation was mainly regulated by soil drainage, as in poorly drained soils, crop production is almost unfeasible.

Land use change, particularly in forested ecosystems,has a direct impact on the global carbon cycle. Consequently, the regional assessment of biomass and the understanding of its current spatial controls are research priorities for regional ecology and land use. Field data and satellite imagery were combined here to map woodlands and estimate their above-ground biomass (AGB) in the Dry Chaco ecoregion of northern Argentina. Allometric equations were used to derive AGB from diameter at breast height data collected at 50 samples during 2007. In order to generate the AGB regional map, this information was later associated with MODIS-Terra spectral data (NDVI) using the Random Forest (RF) method. Finally, AGB spatial patterns were associated with potential biophysical and human controlling factors through correlation and regression analyses. Results indicate that the use of RF and NDVI of the dry season derived from MODIS-Terra was suitable to map regional AGB, what makes this methodology applicable to other dry woodlands. The RF model used to map AGB showed a mean deviation of 2.9 % and a precision of 15 % for one prediction. At this regional scale of analysis, biophysical rather than human factors controlled AGB spatial patterns, in part because the region includes a wide range of environmental situations. Warmer conditions showed a higher biomass, suggesting an energetic limitation for AGB accumulation. However, human controls (distance to towns, cultivation, and roads) also conditioned AGB patterns, suggesting lower AGB values near cultivated areas. The relation between AGB and water availability was surprisingly weak, but partially obscured by the land use history and degradation due to extensive cattle ranching. We propose that a combination of environmental factor and land use affects the AGB regional patterns and promotes unexpected relationships with environmental factors. This work represents the first spatially explicit AGB (patterns and controls) analysis for an extensive subtropical dry woodland area (113,000 km2) and shows how biophysical and human factors co-control regional patterns. Fil: Gasparri, Nestor Ignacio. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentina Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina

Rapidly increasing demand for food, fiber, and fuel together with new technologies and the mobility of global capital are driving revolutionary changes in land use throughout the world. Efforts to increase land productivity include conversion of millions of hectares of rangelands to crop production, including many marginal lands with low resistance and resilience todegradation. Sustaining the productivity of these lands requires careful land use planning and innovative management systems. Historically, this responsibility has been left to agronomists and others with expertise in crop production. In this article, we argue that the revolutionary land use changes necessary to support national and global food security potentially makerangeland science more relevant now than ever. Maintaining and increasing relevance will require a revolutionary change in range science from a discipline that focuses on a particular land use or land cover to one that addresses the challenge of managing all lands that, at one time, were considered to be marginal for crop production. We propose four strategies to increase the relevance of rangeland science to global land management: 1) expand our awareness and understanding of local to global economic, social, and technological trends in order to anticipate and identify drivers and patterns of conversion; 2) emphasize empirical studies and modeling that anticipate the biophysical (ecosystem services) and societal consequences of large-scale changes in land cover and use; 3) significantly increase communication and collaboration with the disciplines and sectors of society currently responsible for managing the new land uses; and 4) develop and adopt a dynamic and flexible resilience-based land classification system and data-supported conceptual models (e.g., state-and-transition models) that represent all lands, regardless of use and the consequences of land conversion to various uses instead of changes in state or condition that are focused on a single land use. Fil: Herrick, J. E.. United States Department Of Agriculture; Estados Unidos Fil: Brown, J. R.. United States Department Of Agriculture; Estados Unidos Fil: Bestelmeyer, B. T.. United States Department Of Agriculture; Estados Unidos Fil: Andrews, S. S.. United States Department Of Agriculture; Estados Unidos Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto de Matemática Aplicada de San Luis; Argentina Fil: Davies, J.. International Union for Conservation of Nature; Kenia Fil: Duniway, M.. US Geological Survey; Estados Unidos Fil: Havstad, K. M.. United States Department Of Agriculture; Estados Unidos Fil: Karl, J. W.. United States Department Of Agriculture; Estados Unidos Fil: Karlen, D. L.. United States Department Of Agriculture; Estados Unidos Fil: Peters, D. P. C.. United States Department Of Agriculture; Estados Unidos Fil: Quinton, J. N.. Lancaster University; Reino Unido Fil: Riginos, C.. University of Wyoming; Estados Unidos Fil: Shaver, P. L.. United States Department Of Agriculture; Estados Unidos Fil: Steinaker, D.. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Twomlow, S.. United Nations Environment Programme; Kenia

We studied the associations between small mammal assemblages and patterns of land use and land- scape structure, and their seasonal variations in temperate agroecosystems. We collected barn owl, Tyto alba , pellets from nest sites located in the Pampean region included in Buenos Aires province (36 sites in winter and 29 in summer). We used Google Earth and SAC-C imagery classification to describe land use and landscape structure around pellet collection sites. In winter, we found a significant relation between the relative abundances of small mammal species and landscape variables. Landscape accounted for 33.2 % of variance in species data. Calomys spp. were relatively more abundant in sites with higher winter crops cover, while Akodon azarae and Oligoryzomys flavescens increased their relative abundances in sites with more grassland cover. The commensal rodents Mus musculus and Rattus spp. were rela- tively more abundant in sites with higher urban cover, or near households and grain storage facilities. We found no signifi- cant small mammal-landscape association in summer. Our results are in agreement with previous studies showing that land use patterns may influence small mammal assemblages. Moreover, our results also show that seasonality plays a major role modulating the intensity of these small mammal- landscape associations in temperate agroecosystems.

Dry subtropical regions, originally hosting xerophytic vegetation, are currently characterized by diverse land cover/use patterns. Using existing biophysical and socio-economic databases, we explored how human contexts influenced land cover, vegetation composition and agricultural production in five distant regions. On average, cultivated areas represented a minor proportion (

Dry subtropical regions (DST), originally hosting woodlands and savannas, are subject to contrasting human pressures and land uses and different degrees of water limitation. We quantified how this variable context influences landscape pattern and vegetation functioning, by exploring the associations between three groups of variables describing (i) human pressures (population density, poverty, and market isolation) and climate (water availability), (ii) landscape pattern (woody cover, infrastructure, paddock size, etc.), and (iii) vegetation functioning (magnitude and stability of primary productivity), in regions of Asia, Africa, Australia, and America. We collected data from global socioeconomic databases and remote sensing products for 4525 samples (representing uncultivated and cultivated conditions), located along 35 transects spanning semiarid to subhumid conditions. A Reciprocal Averaging ordination of uncultivated samples revealed a dominant gradient of declining woody cover accompanied by lower and less stable productivity. This gradient, likely capturing increasing vegetation degradation, had a negative relationship with poverty (characterized by infant mortality) and with market isolation (measured by travel time to large cities). With partial overlaps, regions displayed an increasing degradation ranking from Africa to South America, to Australia, to North America, and to Asia. A similar analysis of cultivated samples, showed a dominant gradient of increasing paddock size accompanied by decreasing primary productivity stability, which included all regions except Asia. This gradient was negatively associated with poverty and population density. A unique combination of small paddocks and high infrastructure differentiated Asian cultivated samples. While water availability gradients were related to productivity trends, they were unrelated to landscape pattern. Our comparative approach suggests that, in DST, human pressures have an overwhelming role driving landscape patterns and one shared with water availability shaping vegetation functioning.

In the last decades, South American ecosystems underwent important functional modifications due to climate alterations and direct human intervention on land use and land cover. Among remotely sensed data sets, NOAA-AVHRR "Normalized Difference Vegetation Index" (NDVI) represents one of the most powerful tools to evaluate these changes thanks to their extended temporal coverage. In this paper we explored the possibilities and limitations of three commonly used NOAA-AVHRR NDVI series (PAL, GIMIMS and FASIR) to detect ecosystem functional changes in the South American continent. We performed pixel-based linear regressions for four NDVI variables (average annual, maximum annual, minimum annual and intra-annual coefficient of variation) for the 1982-1999 period and (1) analyzed the convergences and divergences of significant multi-annual trends identified across all series, (2) explored the degree of aggregation of the trends using the O-ring statistic, and (3) evaluated observed trends using independent information on ecosystem functional changes in five focal regions. Several differences arose in terms of the patterns of change (the sign, localization and total number of pixels with changes). FASIR presented the highest proportion of changing pixels (32.7%) and GIMMS the lowest (16.2%). PAL and FASIR data sets showed the highest agreement, with a convergence of detected trends on 71.2% of the pixels. Even though positive and negative changes showed substantial spatial aggregation, important differences in the scale of aggregation emerged among the series, with GIMMS showing the smaller scale (11 pixels). The independent evaluations suggest higher accuracy in the detection of ecosystem changes among PAL and FASIR series than with GIMMS, as they detected trends that match expected shifts. In fact, this last series eliminated most of the long term patterns over the continent. For example, in the "Eastern Paraguay" and "Uruguay River margins" focal regions, the extensive changes due to land use and land cover change expansion were detected by PAL and FASIR, but completely ignored by GIMMS. Although the technical explanation of the differences remains unclear and needs further exploration, we found that the evaluation of this type of remote sensing tools should not only be focused at the level of assumptions (i.e. physical or mathematical aspects of image processing), but also at the level of results (i.e. contrasting observed patterns with independent proofs of change). We finally present the online collaborative initiative "Land ecosystem change utility for South America", which facilitates this type of evaluations and helps to identify the most important functional changes of the continent. Fil: Baldi, Germán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Nosetto, Marcelo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina Fil: Aragón, Myriam Roxana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina Fil: Aversa, Fernando. Universidad Nacional de San Luis; Argentina Fil: Paruelo, José. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Jobbagy Gampel, Esteban Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi". Universidad Nacional de San Luis. Facultad de Ciencias Físico, Matemáticas y Naturales. Instituto de Matemática Aplicada de San Luis "Prof. Ezio Marchi"; Argentina