Search

Different methodologies try to identify priority conservation areas (PCA) to improve habitat conservation and decrease human pressures over bird species at coarse-scale. Map of potential biodiversity (PB) can identify PCA (high PB values) at different scale levels by considering ecological requirements and distributions through potential habitat suitability (PHS) models. The aim was to elaborate a map of PB of bird species based on PHS models to spatially identify PCA in Santa Cruz, Argentina. Moreover, we want to analysis species’ ecology requirements, and evaluate PB values and spatially identify PCA through two scale levels. We computed 47 models using Environmental Niche Factor Analysis (ENFA) on Biomapper software. Each model was visualized and combined to get a unique map of PB. We analyzed ecological requirements by specialization and marginality and PHS maps. Moreover, considering natural environments (regional level) and forest types’ cover (forest landscape level), we evaluated PB values using ANOVAs and identified PCA under different human pressures, using human footprint (HPF) map. Bird species related to Nothofagus forests were most specialist and exhibited a narrower potential distribution than grassland species. At regional level, Magellanic grass steppes displayed the highest PB values, where most of the PCA had high HPF values. At forest landscape level, ecotone N. antarctica forests had the highest PB values, where PCA with low HFP values were outside current protected networking. We conclude that combining PHS models and the map of PB allowed us to improve bird distribution studies and to assist biodiversity conservation strategies under human pressures.

Flower to fruits × and seed-to-seedling were the most critical transition in the early regeneration cycle of pure and mixed Nothofagus forests, both in coastal and mountain geographic locations. Within mixed forest, the deciduous N. pumilio shows better recruitment performance (e.g., highest transition probabilities) than the evergreen N. betuloides. The evergreen species fails to recruit in the mixed coastal forests for two of the three analysed cohorts, which implies an advantage of N. pumilio over N. betuloides that must be further examined. However, N. betuloides in average value had a higher probability of reaching 2-year survivor in mixed forest. Transition from flower to seedling encompasses major processes that define the success of the tree regeneration, and consequently, its study is crucial in the context of forest management. Here, we analysed the transition probability of the reproductive cycle of two Nothofagus species, which formed pure and mixed forests in coastal and mountain geographic locations of Tierra del Fuego (Argentina). Pure deciduous N. pumilio (Np), pure evergreen N. betuloides (Nb), and mixed N. pumilio–N. betuloides (M) forests in coasts and mountains (3 forest types × 2 geographic locations × 20 replicas = 120 replicas) were evaluated. Reproductive structures (female flowers, fruits, seeds, sound seeds, emerged seedlings and surviving seedlings up to 2 years) were studied since 2012–2018. Our results suggested that transition probabilities from flower to surviving seedlings varied inter-annually between N. pumilio and N. betuloides. The hazard ratio in the transition showed an influence of the cohorts and the geographic location on N. pumilio, while forest type and geographic location influenced on N. betuloides. Flower to fruits and seed to seedling were the most critical process in all forest types and locations. Cumulative transition probabilities (female flowers to 2-year-old seedlings) for N. pumilio were 0.3–46.2% in Np and 1.4–30.2% in M, and pure and mixed forests reached similar probabilities only in cohort 3. For N. betuloides, these were 2.8–24.4% in Nb and 0.0–6.5% in M. Both Nothofagus species showed a better performance of pure forests in mountains (15.9–46.2% Np; 3.8–24.8% Nb) than in coasts (0.3–16.1% Np; 2.8–5.3% Nb). Through this integrated approach, considering the full reproductive cycle, it is possible to quantify the influence of canopy composition and inter-annual variability in natural forest dynamic, and allows to identify the critical stages of tree recruitment in pure and mixed Nothofagus forests.

In forests affected by heavy fires and continuous grazing of exotic herbivorous mammal species, Nothofagus pumilio (lenga) cannot recover naturally. The main factors that hinder the natural recovery of these forests and the feasibility of native tree plantations are the exotic herbivorous pressure, like that produced by Lepus europaeus (European hare), and the environment degradation degree by anthropic disturbances. The objective of this study was to evaluate different plantation efforts to recover N. pumilio forests degraded by fires in Chilean Patagonia. The plantation actions also included wire fences for sapling protection in 100 ha, where 60 ha were established during autumn (May 2012), and 40 ha were established during spring (October 2012). In March 2013 we recorded the height annual growth (cm year−1), the section browsed at each sapling, the modification of plant form (number of new branches), and the vigor expression. We evaluated the data using one- and two-way ANOVAs, Cohen’s d effect size, and chi-square analyses. We measured a total of 872 plants, where 42% presented damages caused by European hare browsing. These results indicated that the wire fences were not completely useful to stop the damage on saplings (Cohen’s d effect size =

Las propuestas silvícolas de los bosques de Nothofagus pumilio se basan en la apertura del dosel para estimular el crecimiento de la regeneración, cambiando la disponibilidad de agua y luz. Las plántulas sobreviven como si fueran especies tolerantes y crecen lentamente por largo tiempo (más de 20 años) bajo altas coberturas. Sin embargo, cuando el dosel se abre debido a la cosecha o volteos por viento, la regeneración reacciona como una especie intolerante, colonizando rápidamente los sectores abiertos. El objetivo del estudio fue efectuar una comparación, analizando las características fisiológicas y morfológicas de plántulas de N. pumilio creciendo en un gradiente de luz bajo condiciones controladas de riego y temperatura.

The purpose of this study was to analyse how visitors valued a socio-ecological system through the use of social media data. We gathered YouTube´s videos of Ushuaia city and its surrounding forested landscapes (Tierra del Fuego, Argentina) posted between 2010 and 2020. We used the screen time (seconds) of each video to compare the value of visitors on biophysical, cultural, and biodiversity attributes of the studied socio-ecological system. Each of the visitors registered differently the same attribute (e.g. mountains, forests, signposts, fauna, among others), therefore we assessed the time each visitor spend on any attribute, that was calculated considering the focus and scale through which it was observed. Based on our analyses, we found a diversity of attributes with different valuation data for each visitor. Attributes were classified as biophysical, cultural, and biodiversity variables, and the origin of the visitors (e.g. regions of the world) was also evaluated, with descriptive and multivariate analyses. Results indicated that visitors give more value to biophysical and cultural attributes compared to local biodiversity. These outputs highlight the need to explore and implement alternative methods to assess the socio-ecological values to achieve management objectives, and to include socio-ecological attributes in the study area as key indicators to create better tools and solutions for conservation issues. In this context, we provide a new insight into how visitors can appreciate different socio-ecological values.

During the last thirty years, shelterwood cuts has been the most applied regeneration method in Nothofagus pumilio (lenga) forests. This treatment was implemented without any consideration of the landscape, and without considering yield gradients (e.g. stand site qualities), environmental restrictions (e.g. soil water availability) or potential natural disturbance factors (e.g. wind exposure). The objective was to evaluate the dynamics of the remnant forest structure and the natural regeneration 10 years after harvesting across the landscape considering different environmental gradients. Sampling plots were established in nine stands distributed across Tierra del Fuego, Argentina (north, east and south areas) where forestry activity has been concentrated during the last years. The selected areas presented differences in the rainfall regime (402 to 446 mm yr-1) and site qualities of the stands (2.6 to 3.3). Forest structure was similar among the studied areas, nevertheless harvesting intensity was variable (30 % to 57 %) generating different remnant basal areas (BA) (22 to 47 m² ha-1) and woody debris accumulation in the forest floor (167 to 230 m³ ha-1) after harvesting, or in combination with local wind-throws. The current forest structure presented differences in BA (6 to 34 m² ha-1) and established regeneration (49 to 110 thousand ha-1) that varied in height (0.6 to 1.0 m) and growth (4.1 to 12.8 cm yr-1) according to the area and the received damage due to abiotic and biotic factors. We can conclude that forests located along the considered landscapes and environmental gradients differentially responded to the proposed silvicultural treatments, where climate influenced over the post-harvest canopy stability and the established regeneration. For this, it is mandatory to define different silvicultural strategies throughout the landscape., El método de regeneración más aplicado en bosques de Nothofagus pumilio (lenga) es la corta de protección. Este tratamiento se implementó sin consideración del paisaje o gradientes de productividad (ej. calidad de sitio), restricciones ambientales (ej. humedad del suelo) o factores de disturbio (ej. viento). El objetivo fue evaluar la dinámica de la estructura forestal remanente y la respuesta de la regeneración luego de 10 años de cosecha en el paisaje considerando gradientes ambientales. Se establecieron parcelas en nueve rodales en distintos sectores de Tierra del Fuego, Argentina (norte, este y sur) donde se concentra la actividad forestal. Las zonas seleccionadas presentan diferencias en el régimen hídrico (402 a 446 mm año-1) y calidades de sitio (2,6 a 3,3). La estructura forestal fue similar entre zonas, pero las intensidades de corta fue variable (30% a 57%) generando diferentes áreas basales (AB) remanentes (22 a 47 m2 ha-1) y residuos forestales (167 a 230 m3 ha-1) luego de la cosecha o por volteos de viento. La estructura forestal actual presenta diferencias en AB (6 a 34 m2 ha-1) y regeneración instalada (49 a 110 miles ha-1) variando en altura (0,6 a 1,0 m) y crecimiento (4,1 a 12,8 cm año-1) por zona y daños recibidos (abióticos y bióticos). Concluimos que los bosques responden diferencialmente a los tratamientos silvícola en los paisajes y gradientes ambientales analizados, donde el clima influye en la estabilidad del dosel y la regeneración. En consecuencia, se hace necesario establecer estrategias silvícolas diferenciales a lo largo del paisaje., Laboratorio de Investigaciones en Madera

Aegorhinus nodipennis (Curculionidae) es una especie nativa de la Patagonia continental de Argentina y Chile, considerada plaga de importancia en cultivos frutihortícolas de Chile. En esta nota se describe su detección y los daños generados en forestaciones y huertas de cascos de estancias de Tierra del Fuego argentina (Ea. Sara y Ea. Viamonte), causando la mortalidad de añosos árboles exóticos de madera blanda (principalmente abedules, sauces y serbales), de valor ornamental paisajístico o en cortinas forestales, desde el año 2017 hasta el presente. Se discute el potencial de invasión y afectación de los ecosistemas nativos de la región, así como de profundizar los estudios sobre su comportamiento en esta región, y la importancia de realizar monitoreos y control para la preservación de la vegetación nativa y la de cascos de estancias, de importancia histórica y cultural para la población fueguina.

In the last years, different spatial analyses were developed to support multi-taxon biodiversity conservation strategies. In fact, the use of species distribution models as input allowed to create spatial decision-support maps. Of special interest are maps of potential biodiversity (MPB), which define distribution and ecological requirements of relevant species and maps of priority conservation areas (MPCA), which define priority areas considering endemism and richness. The objective of this paper was to assess multi-taxon biodiversity based on two different spatial analyses and to test their efficiency to support conservation decision at Patagonia. We computed 119 potential habitat suitability maps (one deer, birds, lizards, darkling-beetles, plants) with ENFA (Environmental Niche Factor Analysis) and 15 environmental variables, using Biomapper software. ENFA calculate two ecological indexes (marginality and specialization) which describe the narrowness of species niches and how extreme are the optimum environmental conditions related to the whole study area. These maps were combined obtaining a MPB and MPCA using Zonation software. Multivariate analyses were performed to compare methodologies, analysing environmental variables, ecological areas, forest types and protected areas. Multivariate and ecological indexes showed that deer, lizards and darkling-beetles presented a narrow range, while birds and plants presented a large range of marginality and specialization mainly related to vegetation and climate. At provincial level, highest potential biodiversity and conservation priority values were related to shrublands and humid steppes. However, MPCA showed higher values related to forests and alpine vegetation due to endemism, while MPB showed differences among forest types. These analyses showed that the most valuable areas were not represented in the protected areas, however, many higher conservation priority values were found inside the protected compared with unprotected areas. Different spatial decision-support maps presented similar outputs at provincial scale, but differed in the forest landscape matrix. Both methodologies can be used to plan conservation strategies depending on the specific objectives (e.g. highlighting richness or endemism).

North American beavers (Castor canadensis) are responsible for the major changes in the Tierra del Fuego Archipelago, altering riparian forests for the long-term. Passive restoration of the areas affected was ineffective in the medium-term (up to 20 years), being necessary active strategies. Plantations in abandoned ponds were made with Nothofagus pumilio and N. antarctica tree species across Tierra del Fuego island (Argentina). In the first experiment, we analysed the influence of biotic and abiotic factors in three micro-habitats in the impacted areas: front and tail of ponds, and cut not-flooded forest areas. Five-years-old N. pumilio seedlings had 39% survival in front, 21% in tails, and 46% in cut areas at year-3 of the restoration experiments, being negatively influenced by plant cover and soil moisture. Lower growth was recorded during year-1 (0.7–0.9 cm yr−1), but increased on time (1.9 cm yr−1 front, 1.6 cm yr−1 tail, 4.3 cm yr−1 cut areas). A second experiment explores the alternative to substitute the tree species to face the harder conditions of the impact and climate change. For this, we conducted a new plantation at four locations across the main bioclimatic zones, where 10–40 cm N. antarctica plants attained 17% survival in meadows (front and tail) and 30% in cut areas, being higher with larger than smaller plants (25% vs. 18%), and where they are mainly influenced by rainfall (4% in sites &lt, 400 mm yr−1 and 41% in &gt, 400 mm yr−1). The main damage was detected in the above-ground biomass due to dryness, but root survival allowed the emergence of new shoots in the following growing season. It is necessary to monitor different Nothofagus species across natural environments in the landscape to determine the feasibility and effectiveness of different strategies in restoration plans, considering the selection of climate-resilient tree species.

Background: Biodiversity supports multiple ecosystem services, whereas species loss endangers the provision of many services and affects ecosystem resilience and resistance capacity. The increase of remote sensing techniques llows to estimate biodiversity and ecosystem services supply at the landscape level in areas with low available data (e.g. Southern Patagonia). This paper evaluates the potential biodiversity and how it links with ecosystem services, based on vascular plant species across eight ecological areas. We also evaluated the habitat plant requirements and their relation with natural gradients. A total of 977 plots were used to develop habitat suitability maps based on an environmental niche factor analysis of 15 more important indicator species for each ecological area (n = 53 species) using 40 explanatory variables. Finally, these maps were combined into a single potential biodiversity map, which was linked with environmental variables and ecosystem services supply. For comparisons, data were extracted and compared through analyses of variance. Results: The plant habitat requirements varied greatly among the different ecological areas, and it was possible to define groups according to its specialization and marginality indexes. The potential biodiversity map allowed us to detect coldspots in the western mountains and hotspots in southern and eastern areas. Higher biodiversity was associated to higher temperatures and normalized difference vegetation index, while lower biodiversity was related to elevation and rainfall. Potential biodiversity was closely associated with supporting and provisioning ecosystem services in shrublands and grasslands in the humid steppe, while the lowest values were related to cultural ecosystem services in Nothofagus forests. Conclusions: The present study showed that plant species present remarkable differences in spatial distributions and ecological requirements, being a useful proxy for potential biodiversity modelling. Potential biodiversity values change across ecological areas allowing to identify hotspots and coldspots, a useful tool for landscape management and conservation strategies. In addition, links with ecosystem services detect potential synergies and trade-offs, where areas with the lowest potential biodiversity are related to cultural ecosystem services (e.g. aesthetic values) and areas with the greatest potential biodiversity showed threats related to productive activities (e.g. livestock). EEA Santa Cruz Fil: Rosas, Yamina Micaela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas (CADIC); Argentina. Fil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina. Fil: Peri, Pablo Luis. Universidad Nacional de la Patagonia Austral; Argentina. Fil: Peri, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas (CADIC); Argentina. Fil: Lasagno, Romina Gisele. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina. Fil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas (CADIC); Argentina

Alpine environments and their temporal changes are rarely studied at high latitudes in the southern hemisphere. We analyzed alpine plants, soil temperatures, and growing-season length in mountains of two landscapes of South Patagonia (46° to 56° SL): three summits (814–1085 m a.s.l) surrounded by foothill grasslands in Santa Cruz province (SC), and four summits (634–864 m a.s.l.) in sub-Antarctic forests of Tierra del Fuego province (TF). Sampling followed the protocolized methodology of the Global Observational Research Initiative in Alpine Environments (GLORIA). Factors were topography (elevation and cardinal aspect) and time (baseline vs. re-sampling for plants, five annual periods for temperatures), assessed by univariate and multivariate tests. Plant composition reflected the lowland surrounding landscapes, with only 9 mountain species on 52 totals in SC and 3 on 30 in TF. Richness was higher in re-sampling than baseline, being assemblages more influenced by aspect than elevation. Mean annual soil temperature and growing-season length, which varied with topography, were related to the Multivariate El Niño Southern Oscillation Index (MEI) but did not show clear warming trends over time. We highlight the importance of long-term studies in mountainous regions of extreme southern latitudes, where factors other than warming (e.g., extreme climate events) explain variations., Laboratorio de Investigaciones en Madera

Land-sharing strategies, as variable retention silvicultural proposals, are useful to mitigate harmful effects of economic activities on forest biodiversity; benefits have been reported worldwide for several organisms. However, we suggest that this approach could be useful to improve beetle conservation not only in forests but also in other ecosystem types, based on the results from Southern Patagonia (Argentina). We studied above-ground beetle communities using pitfall traps in Nothofagus pumilio forests, Mulguraea tridens shrublands, and magellanic steppes. The forests were located in Tierra del Fuego Province, while the shrublands and the steppes were in Santa Cruz Province. In forests and shrublands, we compared retention approaches (aggregated/dispersed retention harvesting in forests, and managed cut and retention strips in shrublands) vs. control situations (without harvesting/cuttings). In dry and humid steppes, both impacted by livestock, we evaluated grazed and exclusion paddocks, comparable to structural retentions (reference areas without grazing do not exist). Richness, abundance, frequency, Shannon-Wiener diversity and Pielou evenness indices, and similarity among assemblages were evaluated using univariate and multivariate statistical tests. In forests and shrublands, retention approaches (aggregated/dispersed and strips) allowed the partial or total maintenance of beetle community richness, preserving them similar to natural and non-impacted ecosystems. In dry and humid steppes, exclusion areas presented significantly different richness, abundance and diversity of arthropod assemblages, but with inverse trends: lower values in grazed areas than in exclusions in dry steppe, and higher values in grazed areas than in exclusions in humid steppe. We concluded that land-sharing could be implemented in forests and non-forest ecosystems to preserve beetle communities, being the variable retention approaches and the grazing exclusion areas good alternatives for private or public lands. Likewise, we consider that legislation to promote conservation (like National Law 26331) should not be only applicable for and implemented in forests, but also in non-forest ecosystems. Fil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sola, Francisco Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego, Antártida e Islas del Atlántico Sur. Instituto de Ciencias Polares, Ambientales y Recursos Naturales; Argentina Fil: Cellini, Juan Manuel. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Laboratorio de Investigaciones en Maderas; Argentina Fil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Río Gallegos; Argentina Fil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Ecologically sustainable forest management aims to preserve ecosystem integrity by providing wood and nonwood values. For this, it is necessary to determine the losses produced by the different management practices in natural forest resilience. The aim was to determine changes in forest structure values along the natural cycle and human impacts generated by rural timber, pastoral and silvopastoral uses in managed, unmanaged, and transformed Nothofagus antarctica forests of Tierra del Fuego (Argentina), as well as in some associated environments (grasslands). We sampled 145 sites to determine landscape characterization, microclimate, soil properties, debris, forest structure and regeneration under different conditions: (i) six phases of natural forest dynamic (even-and uneven-aged), (ii) four types of management and conversion alternatives with and without natural regeneration, and (iii) forest edges and grasslands. Main results showed that stand characteristics (abiotic, soil, forest structure, and regeneration) did not significantly change along the different natural forest phases in even- and uneven-aged structures. However, many studied variables strongly varied depending on harvesting intensities and fire occurrence. The magnitude of these changes was directly related to the impact degree. Multivariate analyses showed a close relationship among the different natural forest phases, and how stands with harvesting or different conversion intensity differ from the control stands, or how much they become similar to openlands. Through different indexes, we related the modifications of the stand characteristics with the magnitude and direction of the changes. Then, these could be used to propose sustainable forest management strategies in the framework of silvopastoral systems., Facultad de Ciencias Agrarias y Forestales

Land use planning is mainly based on monetary values of provisioning ecosystem services (ES). However, many other non-monetary ES and biodiversity provide values for human well-being, and it should be included in the decision-making. The objective of this chapter was to characterize different ES (provisioning, cultural, supporting, regulating) and potential biodiversity in different forest types in Tierra del Fuego Province, Argentina. We map and extract information for provision of ES and biodiversity and compare them through univariate and multivariate methods. We found that each forest type showed different potential biodiversity that determines the need of specific conservation and management strategies. Forest types presented different types and levels of provision of the studied ES, where several synergies and trade-offs were observed according to the current economic activities. Beside this, ES and potential biodiversity of the forests are not equally represented in the currently protected natural reserve network, compared to the values at landscape level. These outputs can be used to improve the current land use planning and the effectiveness of conservation at landscape level.

Cattle grazing and fire are common types of management on natural ecosystems, generating several threats to the conservation of native vegetation (e.g., changes in species richness, cover, and abundance, mainly of bovine-palatable species). In this work, we analysed the response of the structure and composition of vegetation managed with different cattle stocking rates and fire in the savanna ecosystems of Colombia. The study was located in the eastern area of the Llanos region, where savannas were subjected to grazing and burning. Regarding grazing, we classified the area according to the cattle stocking rate (Bos indicus ~300 kg): NG = non-grazed, LS = low stocking rate (0.5 ind ha&minus, 1 yr&minus, 1), and HS = high stocking rate (1.0 ind ha&minus, 1). Controlled artificial burning was applied in all the area at the beginning of the study, and surveys were conducted in the same plots at pre-burn (t0) and four post-burn times (t1, t2, t3, t4), at 15, 45, 75 and 105 days after burning. Vegetation composition (species list, life-form, palatability) and structure (bare soil and vascular plant ground covers, species height and richness) were recorded at each sampling. Data were compared through ANOVAs and multivariate analyses. We found 53 species in total: 26 in the pre-burn treatment and 44 in the post-burn treatments, detecting an increase of 18 species considering all treatments. Seven natives and two exotic species represented the dominant cover (&gt, 50%). LS and HS had the highest number of palatable species in t0 (seven species) compared with NG (two species), but this became similar after burning (14 species in NG, 12 in LS, and 11 in HS). ANOVAs and multivariate analyses showed that plant assemblages were significantly different according to the grazing treatment, and more homogeneous in pre-burn than in post-burn periods. Cattle grazing favored higher covers of dominant palatable species (e.g., Axonopus purpusii) compared with NG, but many native species with high palatability only recovered within the system after burning. In the context of the current management proposals, the search for new alternatives other than intensive cattle grazing and burning is needed to reconcile human production activities, international commitments against climate change and biodiversity conservation in the savanna landscapes.

North American beaver is the most iconic and studied invasive species of Tierra del Fuego. The scientific literature has focused on highlighting the beaver negative impacts on the ecosystems, which have resulted in reduced actions such as eradication. However, the beaver problem in relation to ecosystem services (ES) has been little described or analyzed. This chapter provides a beaver habitat suitability map and discusses the potential positive and/or negative relationships between beaver invasion and ES (provisioning, cultural, supporting and regulating). We found that ES approaches can provide evidence of the beaver role for the people at different archipelago’s vegetation zones. We conclude by outlining how the comprehensive assessment of ES can be a tool that allows to understand and to guide decision-making for the beaver issue.

The role of biodiversity in natural forests is critical as a regulator of ecosystem function, productivity, and provision of ecosystem services. The objective was to analyse the conservation value of Nothofagus forests in Southern Patagonia (Santa Cruz and Tierra del Fuego provinces), Argentina, through integration of maps of potential biodiversity (MPB) and human footprint (HFM), which can help to improve the natural reserve designs through the spatial prioritization of their conservation values. To achieve the, first we determine that the different forest types presented different species assemblage with specific ecological niche requirements which justify differential conservation or management strategies. We used understory plants as proxy, and we selected indicator species of the understory plants for the following analyses. With these species we produce the MPB, and we found that the occurrence of MPB differ from the pattern of HFM according to the different forest types. After that, we identify woodland patches with special values of MPB and low HFM according to the different forest types, and analyzed if the distribution of MPB of the different forest types changed across the current natural protected reserve network, private and public lands. Finally, with these outputs, we propose new methodologies to enhance the current natural reserve network effectiveness. These outputs can be used as a tool to determine new strategies for management and conservation at landscape level in Southern Patagonia.

Rapid urban development threatens biodiversity, reducing local livelihoods and well-being when replacing natural habitat by urban structures. Although there is a lot of literature on the effects of urbanization on biodiversity, little has been investigated in South America. This study evaluated, for the first-time, bird community variation in an urban gradient of Nothofagus South-Antarctic forest in Ushuaia, the southernmost city of Argentina. We also studied differences during the breeding season and habitat characteristics. We conducted bird surveys monthly from October 2016 to February 2017 in 12 plots classified as (i) urban, (ii) peri-urban and (iii) non-urban forest. We counted birds for 15 min (three times per month) in each plot to obtain assemblage richness, abundance, density and several indices (Shannon-Weiner diversity, Pielou evenness and abundance-based Chao-Sorensen similarity) for the communities and functional groups. We recorded use of strata, weather conditions and human/domestic animal presence during counting, as well as habitat variables (forest structure, ground cover and understory plants) in each plot. We performed univariate and multivariate analyses, which showed that urbanization positively affects bird community structure (all variables increased in urban forest), with a reduction in the abundance of insectivores cavity-nesters that feed on trees (Campephilus magellanicus, Troglodytes aedon, Aphrastura spinicauda and Pygarrhichas albogularis). Bird assemblages changed similarities over the season; non-urban forests were more dissimilar than urban and peri-urban in October and November, but not in the other months, highlighting different roles of each forest in different periods. We found differences in habitats along the urbanization gradient, and discuss possible influences on bird communities, such as more food supply associated with berry shrubs and low overall richness at high latitudes. According to our results, urban forests with native vegetation are useful structures that help to maintain native bird communities and ecological functions in Ushuaia city. Fil: Benitez, Julieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Pizarro, J. Cristóbal. Universidad de Concepción; Chile Fil: Blazina, Ana Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina

Usually, stands with aging trees are considered forests with higher conservation values, regardless their structural diversity and other functional attributes. Natural stands present a wide range of age structures, from even-aged stands growing at different development growth phases (e.g. CO = stands at initial or final optimum development growth phase, MD = stands at mature or decaying development growth phases) to uneven-aged stands with mixed development growth phases (e.g. UOG = stands combining mature or decaying development growth phases with initial or final optimum development growth phases, UMD = stands combining only mature and decaying development growth phases). The aim of this work was to compare richness and cover of understory vascular plants of even- and uneven-aged stands of Nothofagus antarctica (nire) forests in Tierra del Fuego (Argentina), and relate these characteristics with abiotic, soil and forest structure variables. A total of 75 stands were sampled across the natural range distribution of the forests, where understory (point intercept method), forest structure (angle count sampling and eye-fish photos) and environmental (soil) variables were measured. 17 one-way ANOVAs were conducted using Tukey test at p UOG > MD > CO (17–28 total, and 13–24 native species, respectively). Neither exotic species richness (4–5 species) nor understory cover significantly changed among treatments (total, dicots, ferns and bryophytes). However, monocots cover significantly differed among treatments (F = 3.9, p = 0.012), where UMD > MD > UOG > CO. Finally, indicator species cover for environmental degradation did not present significant differences (F = 2.1, p = 0.106), but they were positive related to forests growing in mature stages. We concluded that uneven-aged stands presented significantly higher conservation values compared to even-aged stands, where mature/decay stands have better conservation values than optimum growth development phases. These findings can be used for better silviculture practices that combine silvopastoral use and conservation strategies., Facultad de Ciencias Agrarias y Forestales, Consejo Nacional de Investigaciones Científicas y Técnicas

Estimation of biomass and nutrient contents in tree components are essential for evaluating the impact of harvesting on carbon fixation capacity, bio-element recycling, and long-term effect on the balance that influence over net primary productivity. In many reports, fixed values were roughly considered at tree and stand level; however, the nutrient contents can vary across natural gradients (e.g. site quality and crown class) and according tree components (e.g. leaves, branches, bark, wood); and also, can be related to their fibre contents. The objective was to determine these changes in one tree species (Nothofagus pumilio) growing in Southern Patagonia (Argentina), comparing carbon (C), nitrogen (N) and fibre tissue contents of above-ground biomass across site quality and crown class gradients. We found that C, N and fibre (cellulose, hemicellulose, lignin) at different tree compartments varied with the site quality and crown class gradients (dominant, codominant, intermediate, suppressed). High tree growth rate (better site qualities and dominant trees) affected tissue density and fibre content by increasing C content (e.g. lignin generated higher carbon content). Also, we found the same trend for N content, which was more evidently related to some tissues (e.g. leaves). The use of fixed values in the modelling for tree or stand approaches in C or N estimations can generate significant biases in N. pumilio trees, being necessary consider specific values for the different natural gradients that influence over this tree growth species. Calculating accurately the stored and sequestered C or N contents can improve management strategies and modelling of the natural forest stands. The information provided in the present study suggests the need of incorporate the natural gradients into the tree models for C sequestration and N storage estimations.

Berberis microphylla G. Forst. (calafate) is an evergreen and spiny shrub considered as a non-timber patagonian forest product, that is relevant for diversification of agrifood production, particularly interesting since its black–blue fruits are rich in phenolic compounds. The objective of this research is to analyze the variability in floral traits and reproductive success of Berberis microphylla G. Forst. among and within three populations of Tierra del Fuego along three growing seasons. The presence of variability in some floral traits as well as in the reproductive success of B. microphylla among and within three Tierra del Fuego populations was observed, in agreement with the environmental conditions i.e. mean daily temperatures and accumulated rainfall for the three populations and the three growing seasons. Flower dry weight and gynoecium area are good indicators of flower quality (i.e. ovule number), with positive and significant correlations between them (flower dry weight with gynoecium area, r = 0.551; p=

Biodiversity loss remains one of the most pressing issues for global governance. This situation can be seen in Argentina and Chile through the effects of biodiversity loss caused by the introduction and expansion of beavers in Southern Patagonia. This case is interesting because, despite the Beagle conflict (i.e., the border dispute) between these countries some decades ago, nowadays Argentina and Chile are facing shared environmental problems and both are actively seeking solutions. The main question in this paper is, how did Argentina and Chile search for a solution to shared environmental problems caused by the expansion of beavers in Southern Patagonia? This paper tackles this question and presents the results of the conducted qualitative research. The results indicate that, in order to understand what Argentina and Chile are doing to achieve a solution to their shared environmental problems, research cannot be exclusively focus on domestic affairs. Instead, this issue requires taking into account how international dimensions influenced domestic policies. As this paper argues, in Argentina and Chile, international cooperation is a method of influencing biodiversity governance through funds granted by international organizations and international expert recommendations. Fil: Lorenzo, Cristian A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina. Universidad Nacional de Tierra del Fuego. Instituto de Ciencias Polares, Recursos Naturales y Ambiente; Argentina Fil: Kelly, Julián. Universidad Nacional de Tierra del Fuego. Instituto de Cultura, Sociedad y Estado; Argentina Fil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Estenssoro Saavedra, Fernando. Universidad de Santiago de Chile; Chile Fil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina

The comprehensive assessment of environmental gradients influencing species assemblages is important for implementing new conservation strategies under climate change. This study aims to determine the multi-scale effect of altitudinal and longitudinal gradients as drivers of richness and plant community assembly in mountain landscapes of Isla de los Estados (Argentina) to identify areas with greater conservation value in Southern Patagonia. We chose three fjords across the island that extends from West to East and we categorized landscapes into four ecosystem types according to their vegetation type (forests and open-lands) and elevation (lower lands, 0-100 m.a.s.l. and upper lands, 300-400 m.a.s.l.). Forest structure, soil cover (woody debris, rocky outcrop and bare soil) and vegetation cover (vascular and non-vascular), including richness and growth-forms (trees, shrubs, prostrate and erect herbs, tussock and rhizomatous grasses, ferns and inferior plants) were measured in 60 sampling areas (3 fjords × 2 vegetation types × 2 elevations × 5 replicates). ANOVAs and multivariate methods were used to analyse heterogeneity in forest structure, plant richness, and life-form. In addition, species richness and the Simpson's diversity index were calculated to understand plant assembly at multiple-scales (α, β and γ). Our results showed that environmental gradients (altitudinal and longitudinal) are more important drivers of change of ecosystem type than forest spatial structure. Furthermore, forest structure significantly varied with altitudinal and longitudinal gradients affecting most of the studied variables. A greater similarity (in richness and cover) between open-lands of lower and higher elevations was detected, as well as between forests. Fjords showed a West-East gradient, where the western and center fjords were more closely related to each other than to the eastern fjord. A multi-scale diversity approach may play central role in improving our understanding the main environmental drivers of richness and plant community assembly in these forests, both theoretical and empirical, and may be used to identify the spatial scale at which ecosystem types have greater conservation value. This study indicates that for southern forest conservation at regional level, efforts must cover all environmental gradients, including the different vegetation types to assure ful conservation of all the species assemblages. Fil: Huertas Herrera, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina

Mast seeding is characteristic of many long-lived tree species and widely proposed as a mechanism to reduce seed predation. However, whether the efficiency of this reproductive response may vary depending on type of seed predator (e.g., invertebrates vs. vertebrates) or depending on local characteristics, remains seldom explored. We evaluated for 8 yrs the patterns of seed production in antarctic beech (Nothofagus antarctica) forests related to management and its influence on insect and bird pre-dispersal seed predation. Along the study, mature seed production was highly variable across years (the population-level coefficient of variation, CVp: 0.98–1.14) and spatially synchronized (Pearson correlation coefficient: 0.83–0.86). Forest type (primary unmanaged, secondary-growth and managed stands) did not influence the amount of seed production nor masting patterns. Mean yearly seed predation by insects was higher than by birds, and their relationship with seeding patterns differed: i.e., while the proportion of seeds predated by insects increased during non-mast years maximum bird predation occurred in mast years. Therefore, predation by insects and birds showed a strong negative relationship. Our results suggest that effectiveness of masting to escape seed predators may be highly depend on the type of predator. We address whether this effect may be due to differences in life history traits among the seed predators involved (i.e., degree of host specificity, dispersal ability or the duration of the life-cycle) and whether an “imperfect” control of avian seed predation may partially be advantageous for the dynamics of the masting species to enhance seed dispersal. Fil: Soler Esteban, Rosina Matilde. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Espelta, Josep Maria. Consejo Superior de Investigaciones Científicas. Centre de Recerca Ecológica I Aplicacions Forestals; España Fil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Martínez Pastur, Guillermo José. Universidad Nacional de la Patagonia Austral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

El objetivo de este trabajo fue evaluar la utilidad de la base de datos provista por la plataforma global eBird6 para estimar la función ambiental de conservación del hábitat natural y de la diversidad biológica de los paisajes boscosos y esteparios de Tierra del Fuego, a través de la caracterización de su avifauna. Usando eBird se recopiló información sobre observaciones de aves (latitud y longitud, fecha de observación y especies) desde 1973 hasta febrero del 2016

Key message: Canopy composition in mixed Patagonian Nothofagus forests has an impact on soil properties like cationic exchange capacity and pH, while most soil variables changed with site [P, cation exchange capacity (CEC), soil moisture (SM), resistance to penetration (R)]. Site conditions and canopy composition need be considered together to better understand the distribution of Nothofagus species.Context: Forests can influence soil development, changing main soil properties by several mechanisms, but this has never been investigated in mixed Nothofagus forests. Such influences can be strongly variable depending on local site conditions, and the interactions between both factors need to be clearly established.Aims: To reveal the effect on physical and chemical mineral soil properties in mixed Nothofagus forests of canopy composition and their interactions with site conditions.Methods: Two sites and threemixed forest types, with different proportion of deciduous-evergreen,were selected in coastal andmountain sites. We evaluated forest structure, litterfall and physico-chemical properties of mineral soil (N= 60), and analyzed these factors with general linear models and multivariate statistics [multi-response permutation procedure (MRPP), principal component analyses (PCA)].Results: Basal area and litterfall were significantly influenced by forest type × sites. CEC and pH value varied among forests types and sites, but sites also influenced other variables (P, SM, R). Multivariate analyses reveals a much stronger effect of site conditions than that of species mixture.Conclusion: Forest soil studies must consider environmental factors on different spatial scale and canopy species composition to better understand their influence on soil dynamics in mixed Nothofagus forests. Fil: Toro Manríquez, Mónica del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Soler Esteban, Rosina Matilde. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Promis, Álvaro. Universidad de Chile; Chile

Disturbances have frequently been shown to increase the invasibility of plant communities. Harvesting, the most common and severe type of anthropogenic disturbance in forests, creates pulses of enhanced resource availability for alien plants and for native colonizers. However, it is unclear for how long initial changes in species composition of the understorey persist after harvesting. Using annually surveyed permanent plots (n = 72 plots across six stands), we analysed temporal changes of plant understorey composition of Patagonian Nothofagus pumilio forests during 12 years under three different conditions created by variable retention harvesting: retained forest patches (aggregates) of 30 m radius in a density of one patch ha−1 (AR), dispersed retention within the influence of the aggregate (DRI), retained dispersed single trees (DR); and primary unharvested forests as control (PF). Our results show that: (i) cover of native forest species in the understorey declined only very slowly in AR, but alien species cover increased strongly and became dominant nine years after harvesting (YAH); (ii) DR and DRI supported higher cover of alien species in the understorey than AR and PF, and alien species became dominant two to three YAH. Yet, they started to decline following a peak at eight YAH; (iii the cover of native forest species in the understorey was high in the beginning but alien species became dominant in DR and DRI after four and seven YAH, respectively. Tree regeneration significantly influenced understorey dynamics, i.e. (iv) in DR, a negative relationship with alien species cover, and a positive relationship with native colonizers from other habitats; (v) in DR and in DRI, this relationship was negative with alien species richness; (vi) in DRI, it was positive with native colonizers from associated environments (cover and richness). We conclude that alien plants invade Patagonian forests after harvesting, but decline with time when tree regeneration is established. Our results highlight the role of harvesting in facilitating plant invasions in forests, and how the spatio-temporal trajectories of such invasions are influenced by different levels of disturbance created by harvesting according to the position within the resultant matrix. Fil: Soler Esteban, Rosina Matilde. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Rumpf, Sabine B.. Universidad de Viena; Austria. University of Otago; Nueva Zelanda Fil: Schindler, Stefan. Universidad de Viena; Austria Fil: Martínez Pastur, Guillermo José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina Fil: Barrera, Marcelo. Universidad Nacional de La Plata; Argentina Fil: Cellini, Juan Manuel. Universidad Nacional de La Plata; Argentina Fil: Pérez Flores, Magalí. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Essl, Franz. Universidad de Viena; Austria Fil: Rabitsch, Wolfgang. Universidad de Viena; Austria Fil: Lencinas, María Vanessa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Austral de Investigaciones Científicas; Argentina