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Land use and land cover (LULC) change is one of the clearest representations of the global environmental change phenomenon at various spatial and temporal scales. Chile is worldwide recognized to have areas dedicated to non-native forest plantations that specifically in coastal range show high environmental and economic deterioration, questioning the sustainability of the forestry industry. Currently, there are no studies in Chile that reveal the real effects of the LULC change on the water balance at basin or sub-basin scales associated with future scenarios, which might contribute to territorial decision-making and reveal the real magnitude of the effects of these dynamics. In this study, in order to study LULC dynamics in a coastal basin in South-Central Chile, we assessed and analyzed the effects of future LULC change scenarios on the hydrological processes by generating future synthetic land cover maps from Landsat (Landsat 5 TM and Landsat 8 OLI) image datasets. The hydrological model Soil Water Assessment Tool (SWAT) was calibrated and validated, using hydroclimatic time series, to simulate discharges and other hydrological components over those future LULC scenarios. The LULC future scenarios were projected using combined Markov chain analysis (CA–Markov) and cellular automata algorithms for the near (2025), middle (2035) and far (2045) future. The results revealed that the effects on the different components of the water balance of the basin are not as significant except in the soil water transfer in percolation (increase 72.4%) and groundwater flow (increase 72.5%). This trend was especially observed in sub-basins with non-native forest plantations that dominated land cover in the year 2035, in which an increase of 43.6% in percolation and groundwater flows resulted in increased aquifer recharge and water storage, mainly offset by a decrease of 27% in the evapotranspiration. This work demonstrates the importance of evaluating the impacts of the dynamics of LULC on the hydrological response of a coastal basin, and also on how the land use governance and policy are closely linked to that of water resources.

Groundwater (GW) use has intensified in recent decades, threatening the ecological integrity of groundwater-dependent ecosystems (GDEs). The study of GDEs is limited; therefore, integrated, interdisciplinary environmental approaches that guarantee their monitoring and management amid current climate and anthropogenic changes are needed. A new geospatial method with an integrated and temporal approach was developed through a multicriteria approximation, taking into account expert opinion, remote sensing-GIS, and fieldwork to map groundwater-dependent ecosystem zones (GDEZ). A survey of experts (N = 26) was conducted to assign degrees of importance to the various geospatial parameters, and the mapping was carried out using 14 parameters. The reclassified parameters were normalized on a scale of 1 to 5 according to the degree of probability of the presence of GDE. The validation was carried out through fieldwork and statistical analysis. Then, the spatio-temporal changes amid changing GW levels were assessed using the summer season normalized difference vegetation index (NDVI). Two GDEZ maps were obtained, for 2002 and 2017, between which the high- and very-high-probability zones of GDEs decreased by 31,887 ha (~ 38%). The most sensitive temporal parameters that most influenced the spatio-temporal changes on GDEs were precipitation and land use, with rain exerting a slightly the greatest influence. It was also demonstrated that identified ecosystems decreased in area or were affected by aquifer depletion (NDVI-GW, r Pearson ≥0.74). This validated method allows spatio-temporal changes in GDEs to be mapped and analyzed at an annual scale and is transferable to other arid and semi-arid environments.

Native forest deforestation has been identified as one of the main land cover changes affecting flood risk specially during small and moderate storm events. In this regard, forest protection and reforestation are considered a nature-based solution (NbS) for flood regulation. However, there is a lack of knowledge about the effects of different deforestation spatial patterns over floods. Effects of land cover changes on floods in a humid tropical basin within the Ecuadorian Amazon are assessed distinguishing forest location and forest fragmentation. The hydrological distributed model TETIS was applied to simulate the hydrological response of a basin to extreme storms having return periods of 1, 10 and 100 years, considering five land cover scenarios. The model was calibrated and validated using nine storm samples collected at a gauge station during the years 2018 and 2020. The simulated overland flow in hillslopes and stormflows within the river channel were analyzed to i) assess the statistical differences among all land use scenarios with the Kruskal-Wallis test; ii) assess the statistical differences among pairs of both location and fragmentation scenarios through the post-hoc evaluation Dunn test; iii) assess the statistical differences in relation to the baseline. Obtained results indicate that stormflow is less sensitive than overland flow to land cover changes. Forest location have more influence than forest fragmentation over both, overland flow and storm flows. Deforestation of the upper basin represents the worst scenario for flood regulation, thus protection of existing forest, as well as reforestation of deforested areas located in the upper watersheds is a priority for flood risk mitigation and forest conservation. The results enhance our understanding of ecosystem services provided by tropical Andean foothills forests.

Human activities have led to an increase in land use change, with effects on the structure and functioning of ecosystems. The impact of contrasting land uses along river basins on the concentration of colored dissolved organic matter (CDOM) reaching the coastal zone, and its relationship with the carbonate system of the adjacent coastal ocean, is poorly known. To understand the relationship between land use change, CDOM and its influence on the carbonate system, two watersheds with contrasting land uses in southern Chile were studied. The samples were collected at eight stations between river and adjacent coastal areas, during three sampling campaigns in the austral summer and spring. Chemical and biological samples were analyzed in the laboratory according to standard protocols. Landsat 8 satellite images of the study area were used for identification and supervised classification using remote sensing tools. The Yaldad River basin showed 82% of native forest and the Colu River basin around 38% of grassland (agriculture). Low total alkalinity (AT) and Dissolved Inorganic Carbon (DIC), but high CDOM proportions were typically observed in freshwater. A higher CDOM and humic-like compounds concentration was observed along the river-coastal ocean continuum in the Yaldad basin, characterized by a predominance of native forests. In contrast, nutrient concentrations, AT and DIC, were higher in the Colu area. Low CaCO3 saturation state (ΩAr

Comprehensive flood risk assessment requires enhanced understanding of the coevolution of the river and its floodplain occupation. Paleoflood analysis to determine flood prone areas in combination with numerical simulations to estimate flood hazard and a historical analysis of urban development to consider the evolution of exposure to floods is a possible way forward. The well‐documented 2006 extreme flood in the Biobio River system and the impacted metropolitan area of Concepcion, Chile (~1 million inhabitants) was used as a complex scenario to test the reliability of the proposed method. Results showed that flood prone areas determined with hydro‐geomorphological methods are consistent with those computed with numerical models based on detailed digital elevation models. The flood generation via superficial flow pathways resulting in inundated areas could explain that rivers tend to reactivate paleochannels in extreme conditions. Urban development progressively increased the city's exposure to floods from 0 ha in 1,751 to 1,363 ha in 2006 evidencing a lack of appropriate flood risk management. The 100‐year peak discharge resulted in a high flood risk for about 5% of the total urbanized area of Concepcion, and higher discharges are likely to reactivate a paleochannel that crosses the current city centre. We conclude that the proposed paleo hydro‐geomorphology, hydraulic, and urban planning multimethod approach is a necessary tool to enhance understanding of flood risk in complex scenarios to improve flood risk management.

Land use change (LUC) is one of the most conditioning biophysical factors in the hydric regulation although the magnitude of its effects has been little studied. The objective was to analyze the changes in the magnitude of the ecosystem service of water regulation under future scenarios of LUC at watershed scale, taking as case study the municipality of Panguipulli (Los Rios Region, Southern Chile). The methodology was based on the Curve Number method applied through the ECOSER mapping protocol, which estimates the ability to regulate rainfall considering the type of vegetation and the physical characteristics of the soil. Modeling results showed that under a scenario A of increased old-growth forest cover (64 %), watersheds increase their capacity to regulate between 0.4 % and 7.1 %, while in a scenario of increased industrial forest (88 %), watersheds reduced their capacity to regulate between 0.3 % and 0.9 %, considering a single precipitation event in 24 hours. The watersheds with the largest increase in regulation capacity ( x = 11.8 m3 ha-1) had a low initial area of native forest ( x = 15 %), a large area of soil type A and B (40 %) and a smaller area of soil types C and D (21 %). The basins with the largest reduction in regulation capacity ( x = 4.4 m3 ha-1) exhibited a low area of plantations ( x = 5 %), a low area of soil type A and B (32 %) and higher area of soil type C and D (45 %). This information supports the need to focus land use planning efforts on watersheds most exposed to the expansion of plantations.

Effects of plantation forestry on biodiversity are controversially discussed in literature. While some authors stress positive effects, others tend to attribute a largely negative influence to plantations. One important factor steering the influence on biodiversity are management practices. A second important factor is the environmental matrix. Chile offers the option to analyse both factors jointly. The coastal range of central Chile has experienced rapid and widespread replacement of native Nothofagus spp. forests in favour of Pinus radiata plantations. Here, native forests remain limited to small patches surrounded by an environmental matrix of plantations. Management is rather intensive and not designed to maintain biodiversity. While in the coastal range of central Chile the transformation from native forests to non-native tree plantations has almost come to an end, spatial extension of P. contorta and P. ponderosa plantations has just recently begun in Chilean Patagonia. While the management is similar to central Chile, plantations rather exist as small patches surrounded by an environmental matrix of native plant formations (e.g. Nothofagus spp. forests and Nothofagus spp. scrublands). In the framework of this work, effects of the two diametric land usages on biodiversity are assessed and compared. Biodiversity is assessed at the α -, β - and γ -scale. At the α -scale, biodiversity impacts are inferred statistically, using one-way ANOVA and Tukey’s PostHoc test. Biodiversity of plants at both sites is significantly reduced in plantations when compared to native forests or scrublands. Plantation forestry lowers α -biodiversity and does not provide additional habitats for specialists. At the β -scale, weak edge effects due to the presence of native forests are observed. In total, plantation forestry tends to promote plant invasions and impairs the survival of endemics. At the γ -scale, plant species communities where predominantly native and endemic in forests, predominantly introduced in plantations. Positive effects of the more native environmental matrix in Patagonia are not found to be stronger than in central Chile, therefore it is concluded that management imposes a much stronger influence. Results show, that the biodiversity impacts in Central Chile are transferable to Chilean Patagonia, where plantation forestry is increasingly established.

espanolA nivel global mas de la mitad del agua generada a traves del proceso de escorrentia es usada por el hombre. En el centro-sur de Chile las cuencas hidrograficas han sido sometidas a intensas transformaciones territoriales, incluyendo la forestacion masiva con especies exoticas. Este estudio evalua el efecto hidrologico de futuros escenarios de expansion forestal en una cuenca de meso escala (4.340 km²) utilizando el modelo SWAT. Los escenarios fueron construidos a traves del modelo de regresion logistica proyectando el desarrollo forestal hacia los anos 2018, 2028 y 2038. Los resultados muestran una tendencia a la disminucion de los caudales, especialmente en la epoca de estiaje. Para algunos escenarios la disminucion de los caudales de verano supera el 50% respecto al periodo base. Esta tendencia decreciente de los caudales, producto del aumento de la cobertura forestal, es consistente con la reportada por otros autores en cuencas de pequena y meso-escala. EnglishA global level more than half of the water generated through the process of runoff is used by man. In south-central Chile the watersheds have been subjected to intensive processes of land use changes, including expansion of forest plantations with exotic species. This study evaluates the hydrological effects of future scenarios for forest expansion in a basin of mesoscale (4.340 km2) using the SWAT model. The scenarios were constructed through logistic regression model forest development planning to the years 2018, 2028 and 2038. The results of the validation process show that the model has good capacity to represent the hydrology of the watershed under analysis. Simulations indicate a decreasing trend in flows especially in the dry season. For some scenarios, decreasing summer flows exceed 50% respect to the base period. This decreasing trend is consistent with those reported by other authors in basins of small and meso-scale.

The aim of this study was to establish sustainably feasible areas for the implementation of anaerobic co-digestion plants for agricultural wastes (cattle/swine slurries and cereal crop wastes). The methodology was based on the use of geographic information systems (GIS), the analytic hierarchy process (AHP) and map algebra generated from hedges related to environmental, social and economic constraints. The GIS model obtained was applied to a region of Chile (Bío Bío Region) as a case study showing the energy potential (205 MW-h) of agricultural wastes (swine/cattle manures and cereal crop wastes) and thereby assessing its energy contribution (3.5%) at country level (Chile). From this model, it was possible to spatially identify the influence of each factor (environmental, economic and social) when defining suitable areas for the siting of anaerobic co-digestion plants. In conclusion, GIS-based models establish appropriate areas for the location of anaerobic co-digestion plants in the revaluation of agricultural waste from the production of energy through biogas production.

Several impacts over ecosystem services have been produced by land use/cover changes, placing it as one of the main factors driving global environmental change. In the present study, the SWAT model was used to assess the effect of land use/cover changes on the hydrology response in the Andalien river basin from the south-central zone of Chile. Three land use/cover scenarios (LU_1986, LU_2001, and LU_2011) were compared over a period of 30 years (1984&ndash, 2013) to remove the effect of climate variability on hydrology. The results show a significant decrease in total annual flows among the three LU scenarios. The greater differences in the annual flows of 25.05 m3/s were observed between LU_1986 and LU_2011 scenarios. The hydrological cycle dynamics in the basin show an increasing trend of evapotranspiration and surface flows with a significant decrease in percolation and lateral flow on a monthly and seasonal scale. This behavior can be explained by the increasing percentage of the basin area covered by exotic plantations, from 35.22% to 63.93% during the period. The evidence of these changes and the evaluation of their effects are particularly relevant for the long-term sustainable management of water resources.

A new indicator for the accounting effect of landcover is defined based on the integration of thermodynamics (exergy analysis) and ecology (net primary production (NPP)). The indicator NPPEX allows quantifying and assessing the impacts of landuse changes, in spatial and temporally dimensions. This study is focused on the effect of landuse changes on NPP-based exergy for the south-central of Chile from 2000 to 2014. The exergy-based spatially characterization factor (NPPEX) was estimated based on the time series of NPP extracted from MODIS and exergy conversion factor. Finally, the dynamic of NPPEX changes by the transition of each landuse type was studied for identifying the driver force influencing on biomass productivity. Results confirmed the important influence of forestry policy on land use changes, in particular, the forest transitions during the two last decade, which exhibit a cover increase of 28% between 1994 and 2014 established mainly on land destined to crops, native forest, and shrubs. In consequences, the highest land efficiency (NPPEX) was obtained for exotic tree plantations (88.25–91.4 MJex m−2yr−1) during all studied period, due to high carbon stock per square meter associated to its intensive forest management. From the transition of landcover changes point of view, there was produced a positive effect on NPPEX, being the exotic tree plantation expansion the main driver of gains of NPPEX. Nevertheless, this expansion has carried out severe local environmental impacts (i.e., ecosystem fragmentation, biodiversity loss, topsoil compaction, losses of Biobio Basin's morpho-sedimentary regulation capacity, etc.).

espanolResumen: Se estudian las fluctuaciones de siete glaciares del Campo de Hielo Norte y su relacion con variaciones climaticas decadales post Pequena Edad del Hielo, a traves de bibliografia, interpretacion de documentos cartograficos, fotografias aereas, imagenes satelitales y levantamiento en terreno. Variaciones climaticas a escala decadal se obtienen de los registros de las estaciones meteorologicas de Puerto Aysen y Balmaceda. Se constata el retroceso generalizado, continuo y sincronico en ambas laderas del Campo de Hielo, perturbado solo por pequenos avances en las decadas de los 1920s y 1940s. Desde 1972 las precipitaciones disminuyen y las temperaturas aumentan; simultaneamente el ritmo del retroceso glacial se acelera, culminando con un colapso de gran parte de los frentes glaciares en la decada de los 1990s. Los efectos geomorfologicos de este repliegue glacial es la configuracion de una nueva geomorfologia en la zona proglacial y de zonas de peligro asociadas a procesos paraglaciales. EnglishAbstract: We study the fluctuations seven North Ice Field glaciers and their relationship with decadal climatic variations post Little Ice Age, through bibliography, interpretation of cartographic documents, aerial photographs, satellite images and terrain surveys. Decadal climatic variations are obtained from the records of Puerto Aysen and Balmaceda meteorological stations. Widespread, continuous and synchronous glacial regression on both slopes of the icefield is observed, disturbed only by small advances in the 1920s and 1940s. Since 1972 precipitation has declined and temperatures have increased; simultaneously the rate of glacial retreat accelerates, culminating with a collapse of much of the glacial fronts in the 1990s. The geomorphological eff ects of the glacial retreat is setting a new proglacial geomorphology and danger zones associated with paraglacial processes.

Modeling and mapping of cultural ecosystem services (CES) represents a significant gap in ecosystem service research. A GIS-based methodological framework was developed and applied to map agricultural heritage (AH), understood as a non-divisible combination of three cultural services (dimensions, D): the heritage value associated to a culturally significant species (i.e. Chiloé native potato) (D1); the traditional systems of knowledge of AH keepers (D2); and the social relations among them (D3). The final aim of the study was to provide indicators of the “final” service (AHi, measured in a 0–100 point scale) and its benefits (AHB, measured in US$/ha), capable to display areas where high value farmland was located. In essence, AHi comprised a set of biocultural variables validated and weighted by expert opinion. The experts gave the maximum importance to 5 variables: number of native potato varieties cultivated (D1), use of own seed (D1), form in which cultivation knowledge was acquired by the keeper (D2), exchange of own seed (D3), and number of other potato keepers known (D3). In turn, AHB reflected society's willingness to pay for the nonmaterial benefits of AH conservation. Since these benefits “propagate” across space extending from local to unknown and distant beneficiaries, and the aim was to identify the most valuable areas for their capacity to satisfy a potential demand, AHB was spatialized following the approach of “ascribing” the potential benefits to their “point of provision”. Thus the highest values of AHi coincided with the highest values of AHB (US$10.64–8.64 ha−1) a comprised 5608 ha of the landscape, and similarly the lowest values of AHi matched the lowest values of AHB (US$1.69–0.18 ha−1) comprising 13,070 ha of the landscape. Fil: Nahuelhual, Laura. Universidad Austral de Chile; Chile. Fundación Centro de los Bosques Nativos ; Chile. Center for Climate and Resilience Research; Chile Fil: Carmona, A.. Universidad Austral de Chile; Chile. Center for Climate and Resilience Research; Chile Fil: Laterra, Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Balcarce; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina Fil: Barrena, José. Universidad Austral de Chile; Chile. Center for Climate and Resilience Research; Chile Fil: Aguayo, Mauricio. Universidad de Concepción; Chile

Non-native tree plantations (NNTP) are an increasingly relevant global source of timber. Their expansion may lead to tradeoffs with important local ecosystem services (ES) that need to be evaluated for a sound and sustainable landscape planning. For a mountain area in southern Chile, we assessed the effects of NNTP expansion and potential NNTP timber-ES tradeoffs through a spatial tradeoff typology based on ES supply variations. We evaluated changes in prioritized ES (native timber supply, forage supply, water regulation, and recreation opportunities) and NNTP timber supply based on a probabilistic projection of NNTP expansion at two administrative levels (the municipality and small, medium and large farm properties). Results show that NNTP expansion triggered an increase of 361% in NNTP timber supply at the expense of decreases in provision of selected ES, such as forage supply (16.3%), native timber supply (9.4%), water regulation (0.4%) and recreation opportunities (66.8%). Tradeoffs were restricted to small geographic areas but were considerably high in terms of the magnitude of ES supply losses. Tradeoffs were highest in medium farms as compared to small and large properties. Results corroborate that tradeoffs arise from the interplay of several factors, such as ES type and ES productivity, and they are site-specific and scale dependent. If NNTP continue to expand at the current rate (yearly 9.6%) and under the current management (large scale monocultures), significant ES supply changes are inevitable. These results can inform landowners, landscape planners and governments to better anticipate and mitigate tradeoffs arising from afforestation.

Land use and cover change (LUCC) is among the most important factors affecting ecosystem services. This study examines the influence of LUCC on recreation and ecotourism opportunities over three decades in southern Chile. An in-depth analysis of the transition matrix was conducted based on Landsat images from 1976, 1985, 1999 and 2007. Main LUCC trajectories were linked to two ecosystem service indicators: (i) Recreation and ecotourism potential, measured in a 0–100 point scale; and (ii) Recreation and ecotourism opportunities, measured in visitors/ha. A total of 900 trajectories occurred in the landscape between 1976 and 2007. The most important trajectories in terms of area, were the recent degradation of old-growth to secondary forest between 1999 and 2007 (23,290 ha; 13.5 % of landscape), and the early clearing of shrublands for agriculture and pasture land between 1976 and 1985 (7,187 ha, 4.2 % of landscape). In turn, the single most influential trajectory on the magnitude of the indicators was early and permanent degradation of old-growth forest to secondary forest. As a result of these landscape changes, recreation and ecotourism opportunities for the entire landscape were reduced from 65,050 persons in 1976 to 25,038 persons in 1985, further declining to 22,346 and 21,608 persons in 1999 and 2007, respectively. This decrease resulted from changes in specific attributes (i.e. emblematic flora and fauna and forest structure) that were affected by forest degradation and fragmentation. These results highlight the substantial impact of LUCC on recreation opportunity decline, which mirrors biodiversity losses in the study area.

Andean watersheds present important snowfall accumulation mainly during the winter which is later melted during spring and part of the summer. The effect of snowmelt on the water balance can be critical to sustain agriculture activities, hydropower generation, urban water supply and wildlife. In Chile 25 % of the territory between the Valparaiso and Araucanía Regions comprise areas where snow precipitation occurs. As in many other difficult-to-access regions of the world, in the Chilean Andes there is a lack of hydrological data like discharge, snow courses, snow depths, which complicate the analysis of important hydrological processes (e.g. water availability). Remote sensing provides a promising opportunity to enhance the assessment and monitoring of the spatial and temporal variability of snow characteristics, like Snow Cover Area (SCA) and Snow Cover Dynamic (SCD). In the above mentioned context the objectives of this study are to evaluate the suitability of MOD10A2 to estimate SCA and to assess SCD at five watersheds (Aconcagua, Rapel, Maule, Biobío and Toltén) located in the Chilean Andes, between latitude 32.0º S and 39.5º S. Those watershed were chosen because their importance in terms of number of inhabitants, and dependence of economic activities on water resources. SCA area was obtained from MOD10A2 for the period 2000–2013 and SCD was analysed through a number of statistical tests to explore observed trends. Prior of obtaining SCA for trend analysis, a validation of MOD10A2 product was done; comparing presence of snow predicted by MODIS with ground observations. Results indicate that there is an overall agreement from 81 to 98 % between SCA-determined from ground observations, and MOD10A2, showing that MODIS snow product can be taken as a feasible remote sensing tool for SCA estimation in South-Central Chile. Regarding SCD no significant reduction in SCA area for 2000–2013 was detected, with the exception of the Aconcagua and Rapel watersheds, although an important decline in SCA for the period of 2012 and 2013 was also evident, which is coincident with the rainfall deficit for the same years. Findings were compared against ENSO episodes occurring during 2010–2013, detecting that Niña years are coincident with maximum SCA during winter in all watersheds.

The diel variation of temperature in mesoscale river reaches (catchment area > 1000 km2) is analysed using concurrent measurements of water temperature and of those meteorological (incident short-wave radiation, air temperature, relative humidity and wind speed variables) and hydraulic variables (streamflow, top width, channel slope and flow depth) controlling the thermal regime. Measurements were taken along two river reaches located in central Chile, on the Itata (11 290 km2, Strahler's order 6, reach length 30 km, Qbankfull = 400 m3 s−1) and Vergara (4340 km2, Strahler's order 5, reach length 20 km, Qbankfull = 85 m3 s−1) rivers. The measuring frequency was 15 min. The relevant energy fluxes at the air–water interface, that is, atmospheric long-wave radiation, net short-wave radiation, radiation emitted by the water body, evaporation (latent heat) and conduction heat are computed and analysed for four scenarios of 12 days duration each, representing typical conditions for the austral winter, spring, summer and autumn. We find large differences in the diel river temperature range between the two sites and across seasons (and thus, flows and meteorological conditions), as reported in previous studies, but no clear relationship with the controlling variables is overtly observed. Following a dimensional analysis, we obtain a dimensionless parameter corresponding to the ratio of solar-to-stream power, which adequately explains the diel variation of water temperature in mesoscale rivers. A number of our own measurements as well as literature data are used for preliminary testing of the proposed parameter. This easy-to-compute number is shown to predict quite well all of the cases, constituting a simple and useful criterion to estimate a priori the magnitude of temperature diel variations in a river reach, given prevailing meteorological (daily maximum solar radiation) and hydrologic–hydraulic (streamflow, mean top width) conditions. Copyright © 2012 John Wiley & Sons, Ltd.

Ecosystems can act as both sources and sinks of allochthonous nutrients and organic matter. In this sense, fjord ecosystems are a typical interface and buffer zone between freshwater systems, glaciated continents, and the coastal ocean. In order to evaluate the potential sources and composition of organic matter across fjord ecosystems, we characterized particulate organic matter along a lake–river–fjord corridor in the Chilean Patagonia using stable isotope (δ13C) and lipid (fatty acid composition) biomarker analyses. Furthermore, estimates of zooplankton carbon ingestion rates and measurements of δ13C and δ15N in zooplankton (copepods) were used to evaluate the implications of allochthonous subsidies for copepods inhabiting inner fjord areas. Our results showed that riverine freshwater flows contributed an important amount of dissolved silicon but, scarce nitrate and phosphate to the brackish surface layer of the fjord ecosystem. Isotopic signatures of particulate organic matter from lakes and rivers were distinct from their counterparts in oceanic influenced stations. Terrestrial allochthonous sources could support around 68–86% of the particulate organic carbon in the river plume and glacier melting areas, whereas fatty acid concentrations were maximal in the surface waters of the Pascua and Baker river plumes. Estimates of carbon ingestion rates and δ13C in copepods from the river plume areas indicated that terrestrial carbon could account for a significant percentage of the copepod body carbon (20–50%) during periods of food limitation. Particulate organic matter from the Pascua River showed a greater allochthonous contribution of terrigenous/vascular plant sources. Rivers may provide fjord ecosystems with allochthonous contributions from different sources because of the distinct vegetation coverage and land use along each river’s watershed. These observations have significant implications for the management of local riverine areas in the context of any human project that may modify terrestrial habitats as well as the productivity, food webs, and community structure of rivers, lakes, fjords, and the coastal ocean in the Chilean Patagonia.

A multidisciplinary approach is followed for analysis of the effect of changes in land use patterns on the hydrologic response of the Vergara watershed (4340 km2) located in central Chile. Probable future land use scenarios were generated using heuristic rules and logistic regression models, in order to identify and represent the main pressure on the watershed, namely forestation of extensive areas used for agriculture with rapid growing exotic species. The hydrologic response of the watershed was computed with a physically based distributed precipitation-runoff model, which was calibrated and validated for the current period. Results show that mean annual discharge increase with agricultural land use and diminish with introduced forest coverage. Thus, forestation of areas with introduced species like Pinus radiata and Eucalyptus globulus might be regulated in order to protect the water resources of the watershed.

Alien conifer invasions are affecting ecosystems across the globe, but until recently, reports of such invasions in South America were scarce. Pinus contorta was first established in Chilean Patagonia for erosion control caused by historical fires and cattle farming. Recently, the species has been planted over large areas for commercial purposes. It is well adapted to local conditions and is now spreading into natural areas. This study analyzes natural regeneration of Pinus contorta around Coyhaique city, Chile, to determine the spatial patterns of invasion. Five study sites were selected, four with grasslands dominated by exotic species and one site in the steppe. In each site, the plantation (seed source) was characterized using morphological attributes and density. Regeneration, density, height and age at different distances from the seed source were recorded, and ground cover was measured as an environmental factor influencing the invasion process. A comparative analysis was also conducted between the situation in Chile and other countries affected by P. contorta invasion. In Chile, P. contorta regeneration is significantly influenced by distance from the seed source. Higher densities are found close to the parent stand (up to 13,222 trees ha−1), decreasing as distance from the seed source increases. Age and height structure indicate that the invasion process is at an early stage, and this offers a unique opportunity to study the process of invasion and to monitor it over time. In order to preserve the distinctiveness of Patagonian ecosystem, decisive action is required to control invasive conifers, with P. contorta as the number one priority. Relative to control, there is much that can be learnt from the experiences of other countries, such as New Zealand.

Urban growth patterns of Chilean mid-cities are explored, analyzing land use/land cover changes between 1955–1978 and 1978–1998 in Los Angeles, a mid-city located in central Chile. Urban sprawl is analyzed with respect to population growth and possible effects on the city's socio-spatial structure. Markov's matrix was used to analyze sequences of land use/land cover changes, whereas regression analysis was used to study the relationship between city and population growth. The study is based on remotely sensed data and processed in a GIS environment using Arcview 3.2, IDRISI, and Arc-Info N.T.

El Parque Nacional Torres del Paine (TDP) es un area donde las plantas invasoras son una amenaza creciente para la conservacion. El aumento de turistas ha propiciado durante los ultimos anos un incremento de invasoras en sitios donde el turismo tiene impacto directo (e.g. areas de camping, senderos). En ocasiones, turistas negligentes han provocado mega-incendios que han favorecido la dispersion de estas plantas. En este trabajo se revisa la informacion concerniente a las plantas exoticas en TDP, y se utiliza un marco conceptual para abordar esta problematica, que incluye conceptos jerarquicos de invasibilidad. Se presentan resultados para dos experiencias en donde este marco conceptual tiene aplicacion: a) una prospeccion en que se evalua la distribucion y abundancia de exoticas post-incendio; b) un experimento de campo donde se evalua el efecto del control de invasoras en la supervivencia de plantulas de lenga (Nothofagus pumilio). Ademas se entregan antecedentes que permiten calcular el costo de la operacion de control. La investigacion sobre plantas exoticas en TDP incluye listados de especies que categorizan a priori las invasoras, careciendo de informacion ecologica de campo. Se detecto la presencia de 34 especies de plantas exoticas en sitios incendiados, algunas de ellas con gran potencial de invasion post-incendio. La supervivencia de plantulas de Lenga es mayor cuando se han controlado las malezas mediante remocion mecanica, posiblemente debido a la facilitacion inducida. Los costos de control de especies de malezas mediante remocion mecanica pueden fluctuar desde CLP$ 700.000 a $1.400.000 para el control de 1 hectarea. Este estudio resalta la necesidad de considerar a las especies invasoras como un fenomeno contexto-dependiente, que puede o no persistir dependiendo del tipo de perturbacion que facilite su dispersion, grados de severidad, tiempo post-perturbacion y resiliencia ecosistemica. Abstract Torres del Paine National Park (TDP) is an area in which invasive plants are a growing threat for the biodiversity conservation. The growing number of visitors in TDP has allowed in the last years the increase of invasive species in places where tourism has a direct impact (e.g. camping areas, trails). In other occasions negligent tourists have set mega-fires that stimulate the dispersion of this plants. In this work we review the information concerning on alien plant species in TDP and we use a conceptual framework widely accepted to address this problematic. We present the results of two field experiences in which this conceptual framework has been applied: a) a prospection where the distribution and the abundance of post-fire exotics are evaluated; b) a field experiment in which we evaluated the effect of invasive plant control on Lenga seedlings. These seedlings were planted with reforestation purposes. Furthermore we give the background that allows the calculation of the monetary costs of the weed control. The investigation of alien plant species includes checklists that categorize a priori the invasive species, lacking of field ecologic information. We recorded the presence of 34 exotic plant species in burned places, some of them having a great post-fire invasibility potential. Meanwhile in the sites where reforestation occurs the survival of lenga beech seedlings is higher when the weeds has been controled by mechanical removal, likely by the facilitation induced by control. The costs of weed control fluctuate from CLP$ 700.000 to 1.400.000 per hectare (USD$ 1.135 to 2.270). This study highlights the need to consider the invasive plant species as a context-dependent phenomenon that may or may not persists, depending on the type of disturbance that facilitates their dispersion, severity, post-disturbance time and ecosistemic resilience.

This paper analyzes the impact that the Chilean government’s land-ownership policies have had on the Mapuche-Pehuenche communities, especially with respect to the control of their territory and natural resources. The results show a tendency towards nonprotection of their rights to control their territories with an increasing loss of autonomy and control over land. State intervention, together with large private investment projects, has generated socio-economic and territorial impacts in the indigenous areas, such as the migration of young persons, socio-cultural changes, and conflicts over access and use of ecological zones. The territorial re-ordering of the original Mapuche space, combined with its increasing appropriation by private actors and the Chilean government, has produced a subordinated integration of the indigenous communities with respect to

Una revisión bibliográfica de inundaciones fluviales históricas en el período 15742012 a través de diferentes publicaciones, permite analizar, explicar y sistematizar causas o factores detonantes, periodos de recurrencia, distribución y efectos geográficos de las inundaciones acaecidas en Chile continental. Según el factor detonante se identifican 5 tipos principales de inundaciones asociadas a: procesos volcánicos, procesos nivoglaciares, deslizamientos, intervenciones antrópicas y precipitaciones; estas últimas causan el 71% de las inundaciones en el período analizado. A nivel nacional, se observa un patrón zonal de los tipos de eventos dividido en 5 áreas homogéneas, cuya mayor recurrencia se concentra en el dominio climático mediterráneo, consistente con montos pluviométricos intensos y cambios ambientales ocurridos durante las últimas tres décadas. Se constata un incremento de inundaciones catastróficas, relacionadas principalmente con procesos nivoglaciares e intervenciones antrópicas, desde la segunda mitad del siglo XX a la fecha. A literature review of river floods from 1574 to 2012, allows us to analyze and identify the causes or trigger factors, recurrence periods, spatial distribution and geographical effects of flooding within continental Chile. Five types of flooding are identified, based on the triggering factor: volcanic processes, snow/glacial processes, landslides, anthropic interventions and rainfalls. Rainfall is responsible for 71% of flooding events during the period studied. We were able to spatial patterns at a national level, allowing us to define five homogenous zones. The area with the most frequent events corresponds to the Mediterranean climatic domain, which has been characterized by intense storms and environmental changes over the last three decades. An increase in catastrophic flooding from the second half of the 20th century to the present was observed, primarily associated with nivo-glacial processes and human interventions.

A través de un análisis histórico documental se reconocen los efectos del impacto humano en el territorio insular de Aysén, entre los siglos XVI y XIX. Los resultados obtenidos permiten reconstruir un proceso de intervención ambiental que alcanzó su peak en la segunda mitad del siglo XIX, marcado por una notoria degradación de los ecosistemas locales debido a la caza comercial de pinnipedos y la tala maderera del ciprés de las Guaitecas. Se constata que las alteraciones del paisaje natural derivadas de la actividad aborigen basal y de aquella asociada a la colonización española de Chiloé, fueron leves a moderadas; sin embargo, en el aspecto cultural, la mencionada colonización fue determinante en la desaparición de la población indígena que ocupaba los archipiélagos aiseninos. Se verifica además que las características biogeográficas y fisiográficas del territorio atenuaron los adversos efectos ambientales generados por la actividad antrópica histórica, contribuyendo a la preservación del paisaje ecológico insular.

The effects of a perturbation gradient on a Patagonian rodent community were assessed over the course of a year by comparing the community parameters in natural and different disturbed environments in the central Chilean Patagonia. The studied habitat types were mature forest, second-growth forest, forest plantations, and agricultural grassland. We recorded eight species of sigmodontine rodents (

The question of how ecosystem services can be spatially defined and visualized continues to be challenging, particularly for cultural services such as recreation and ecotourism. This study proposes a methodological framework that combines Geographic Information System and participatory methods (Delphi method and Analytic Hierarchy Process) to map recreation and ecotourism at the municipality level. Attributes selected were singular natural resources, scenic beauty, accessibility, tourism attraction capacity, and tourism use aptitude, which were represented by specific spatial criteria validated and weighted by experts. Two types of indicators were obtained and mapped: i) Recreation and ecotourism potential (REPf) which, based on the selected attributes, measured recreation potential in a 0–100 point scale; and ii) Recreation and ecotourism opportunities (REOi), which adjusting REPf by carrying capacity, measured the visitors per hectare that could sustainably recreate in the study area. The resulting maps were highly consistent with the distribution of areas recognized by the tourism authorities as of interest for recreation development (i.e. areas with emblematic flora and fauna and the presence of public and private protected areas). Overall, the methodology demonstrates an important potential for identifying recreation areas to inform local decision making regarding land use planning.

En este trabajo se estimó la pérdida y fragmentación de bosque nativo en la cuenca del río Aysén, ocurrida entre los años 1900 y 1998, debido principalmente a incendios forestales producto de la colonización del territorio. En la reconstrucción de la cobertura boscosa fueron de gran utilidad distintos registros históricos y el sistema de información geográfica (SIG ArcView 3.2). Se aplicaron diferentes índices del paisaje (área, densidad y tamaño del fragmento, área núcleo total, distancia euclidiana, índices de forma y de agregación, y longitud de borde total), evaluándose los cambios en los patrones de distribución del bosque nativo entre 1900 y 1998. Se reconoció que el bosque perdido fue reemplazado mayormente por praderas, evidenciándose una pérdida aproximada del 23%, de bosque nativo, identificándose además un aumento de fragmentos menores a 100 ha, y la disección de estos debido a los incendios generados durante la colonización. Sin embargo, dichos fragmentos presentarían una alta conectividad, situación que fue corroborada a través de diferentes índices de paisaje. This work estimates the loss and fragmentation of native forest in the watershed of the river Aysén during the 20th century, as a result of clearance fires induced by land settlers. In order to generate the reconstruction of the native forest cover, several documentary records and GIS ArcView 3.2 were used. Different indexes of landscape changes were applied (area, density and size of the fragment, core area, euclidean distance, shape and aggregation index, and edge length) to estimate the distribution of the native forest between 1900 and 1998, which indicate that the main replacement of the forest was by prairies. A loss of approximately 23% of native forest was registered, also an increase in the number of forest fragments (

The historical behaviour of Cipreses glacier from the nineteenth through the early twentieth century is described based on written records, cartography, iconography and photographs. These data allow us to infer that the last maximum advance of Cipreses glacier attributable to the ‘Little Ice Age’ occurred around AD 1842. The first historical retreat was recorded in 1858 and, since then, the glacier has shown a clear retreating trend with no new advances. All this information was compared with the historical data gathered for San Rafael glacier, which shows the occurrence of a cold period contemporary with the European LIA. Whereas Cipreses glacier was retreating by 1858, San Rafael glacier was advancing, reaching its last maximum between 1857 and 1875. The dates for the advances and retreats reveal a time-lag of approximately 30 years in the responses of these glaciers. The comparison of timing in glacier advances suggests that this time-lag is due to changes in precipitation and temperature associated mainly with fluctuations of the Westerlies.

Las coloraciones anormales en los mamiferos marinos ocurren en muy baja frecuencia. Estas coloraciones atipicas son clasificadas como albinismo, melanismo y leucismo, siendo esta ultima coloracion registrada con mas frecuencia en Arctocephalus gazella. En este articulo se documenta el primer caso de leucismo en un ejemplar de Otaria flavescens observado en la zona austral de Chile, asi como de una actualizacion de coloraciones atipicas informadas en otaridos.

Past ice lobe behaviour at Laguna San Rafael is described in documents provided by Spanish and then Chilean explorers from the late seventeenth to the early twentieth centuries. These records begin in AD 1675, when temperate conditions, probably similar to those at present, prevailed. At that point, the glacier was confined within its valley, not penetrating the Laguna. The glacier advanced noticeably during the nineteenth century and probably reached a maximum position for the `Little Ice Age' around AD 1875. The historical sources suggest a slight retreat in AD 1904 in relation to the conditions prevailing 29 years earlier. The historical data show that the eighteenth to nineteenth century cooling period at San Rafael glacier was within the temporal window of the European `Little Ice Age'. This work provides independent, direct historical evidence for the occurrence of this event in southern Chile.

Through development of a spatial simulation model of the land use change it is evaluated and predicted the increase of the surface runoff coefficient in Los Angeles city, Biobio region, between years 1998 and 2022. The model has been developed in the SIG Idrisi Kilimanjaro integrating Markov Chains, Multi-Criteria Evaluation and Cellular Automata. The assessment of the surface runoff coefficient is based on the method of USSCS. The use of spatial models represents a powerful tool to analyze the environmental effects of the urban development, from a geographic approach.

Urbanization is increasingly homogenizing the biota of less developed countries. Even though urban sprawl is a worldwide problem, most studies on the effects of urbanization, and the conceptual models have focused on developed countries. South America has not escaped urbanization, and here we discuss the potential impacts of urban sprawl with respect to three ecosystems in the metropolitan area of Concepcion, Chile. We consider this area a good model and fairly representative of other cities in developing countries which are also experiencing rapid and uncontrolled growth. We found that the impacts of urban sprawl on biodiversity in the metropolitan area of Concepcion differ little from cities in other parts of the world: native ecosystems are replaced by pavements and buildings and what is left of the natural soil is covered with green areas dominated by non-native ornamental species. Wetlands and other peri-urban ecosystems are rapidly being destroyed, fragmented or invaded by non-native species. We found that from a study area of 32,000 ha, there was a net loss to urbanization of 1734 ha of wetlands (23% of the original) and 1417 ha (9%) of agricultural, forest and shrub land cover types between 1975 and 2000. From the total area urbanized (3151 ha), 55% corresponded to wetlands and 45% to agricultural, forest and shrub lands cover types. We see the lack of environmental awareness as a major cause of the increasing deterioration of biodiversity in urban areas of developing countries. More research is needed to fully understand the effects of urban sprawl on the biodiversity of developing countries to include these ecosystems in global conservation strategies.