No abstract

Land-use change can have negative effects on threatened species by modifying their habitat and population dynamics. The habitat of the Endangered Patagonian cypress Fitzroya cupressoides (Mol.) Johnst. (Cupressaceae), a conifer endemic to the temperate forests of southern Chile and Argentina, has been transformed by land-use change and overexploitation. The impact of landuse change on the spatial pattern of F. cupressoides habitat from  to  was evaluated at the landscape level, using satellite images. Additionally, eight  ×  m plots were established in four populations to assess their status. In each plot the density of F. cupressoides and the species richness of the associated plant communities were recorded and analysed, together with spatial patterns at the population and community levels. The loss of potential F. cupressoides habitat was % from  to  (-% for the four populations). The density of F. cupressoides was lowest in smaller habitat patches, where the number of plant species was higher and the matrix dominated by anthropogenic landuse. Land-use change was associated with a loss of potential habitat for F. cupressoides, and differences in the spatial patterns of habitat influenced the composition of remaining populations and communities. A landscape approach is recommended as a conservation planning strategy for F. cupressoides.

Currently, there is no precise information on the degree of transformation of Tropical Andes hotspot landscape and native ecosystems due to the intensification of agricultural and urban land-use. Proper knowledge of these changes would provide crucial information for planning conservation strategies. We evaluated the impact of the intensification of agricultural and urban land-use on the Inter-Andean Dry Forest and Tropical Montane Forest, both of which are categorized as Critically Endangered, and the state of the landscape in the High Rio Guayllabamba watershed, Ecuador, during the periods 1991–2005 and 2005–2017. The evaluation was carried out using Landsat satellite images of 30 x 30 m pixels and landscape metrics. We found an advanced state of landscape transformation. Since the 1990s, the loss of both ecosystems was largely caused by the conversion of forest to agriculture, resulting in substantial changes in the spatial configuration of these ecosystems. From 1991 to 2017, 19.8 % and 16.1 % of Inter-Andean Dry Forest and Tropical Montane Forest respectively, were converted to agriculture. The loss of Inter-Andean Dry Forest was 28 % and the number of forest patches increased by more than 150%. The loss of Tropical Montane Forest was 16.5 % and the number of forest patches increased by more than 300 %. The largest loss and fragmentation of forest cover occurred from 1991 to 2005. We suggested planning landscape-scale conservation, using the patch-corridor-matrix model. This model is appropriate given the current configuration of the landscape studied, with Inter-Andean Dry Forest and Tropical Montane Forest restricted to small patches sparsely distributed across the landscape.

Congruencias espaciales entre biodiversidad y servicios ecosistémicos en un paisaje forestal en el sur de Chile: bases para la planificación de la conservación SUMMARY There is a need for a better understanding on how biodiversity and ecosystem services are spatially related and assess to what extent the conservation of biodiversity will ensure the provision of services. In the Río Cruces watershed (Chile) the spatial congruence between biodiversity and water supply, erosion control and soil accumulation services was assessed using spatially explicit models, geographically weighted regression and overlap analyses. Biodiversity registered a positive spatial relationship with the three ecosystem services. The local R 2 value explained up to 95 %, 68 % and 37 % of the variance for soil accumulation, water supply and erosion control, respectively. High spatial congruence (> 67 %) was registered between biodiversity and ecosystem services hotspots. Our study recommends that decision makers develop plans and share efforts for conservation of biodiversity and ecosystem services in 43 subwatersheds, which are 16.4 % of the subwatersheds studied. We suggest that these efforts must be an integral part of environmental policies that need to be generated by the Chilean government.Existe la necesidad de generar una mejor comprensión sobre cómo la biodiversidad y los servicios ecosistémicos se relacionan espacialmente y evaluar en qué medida la conservación de la biodiversidad asegura la provisión de servicios ecosistémicos. En la cuenca del río Cruces, en el sur de Chile, la congruencia espacial entre biodiversidad y los servicios ecosistémicos provisión de agua, control de erosión y acumulación de suelo fue evaluada usando modelos espacialmente explícitos, regresiones geográficamente ponderadas y análisis de superposiciones. La biodiversidad registró una positiva relación especial con los tres servicios ecosistémicos. El valor de R 2 local explicó hasta un 95 %, 68 % y 37 % de la varianza para los servicios acumulación de suelo, provisión de agua y control de erosión, respectivamente. Alta congruencia especial (> 67 %) se registró entre biodiversidad y los hotspots de los tres servicios ecosistémicos. Este estudio recomienda a los tomadores de decisiones desarrollar planes y esfuerzos compartidos de conservación para la biodiversidad y los servicios ecosistémicos en 43 subcuencas, las cuales comprenden el 16,4 % de las subcuencas estudiadas. Además, es necesario que los esfuerzos compartidos de conservación sean parte integral de políticas ambientales, las cuales deben ser generadas por el gobierno de Chile.Palabras clave: paisajes antrópicos, paisajes cambiantes, bienestar humano, capital natural, modelos espacialmente explícitos.

The forest landscape of southern Chile, which includes Chilean temperate forest ecosystem, has been designated as a hotspot for biodiversity conservation. However, this landscape has been transformed by land-use change. A proper knowledge about how land-use change impact this ecosystem would provide crucial information for planning conservation strategies. At the commune of Arauco – Chile, the impact of the land-use change on the spatial pattern of native forest ecosystem from 1990 to 2010 was evaluated at the landscape level. This evaluation was carried out using satellite images, landscape metrics and spatially explicit models. The loss of native forest ecosystem was of 40.7% (loss rate of 4.39% per year). Conversely, the exotic species plantations increased more than 150%. The number patches of native forest ecosystem increased more than 130%. The size distribution of patches (<100 ha) increased more than 22%. The aggregation index of native forest ecosystem decreased from 62.5 to 40.1. The loss of native forest ecosystem was caused by the expansion of exotic species plantations, which was associated with substantial changes in the spatial pattern of the forest landscape. As a strategy for conservation of the native forest ecosystem we suggest a landscape approach, using the corridor–patch–matrix model. We recommend that this strategy be complemented with land-use planning. Moreover, this strategy must be supported by a framework of environmental policies. We also recommend strengthening the existing ecological restoration programmes and developing new programmes to restore the native forest ecosystem.

Pérdida y fragmentación de ecosistemas boscosos nativos y su influencia en la diversidad de hábitats en el hotspot Andes tropicales Loss and fragmentation of native forest ecosystems and its influence on habitat diversity in the Tropical Andes hotspot

La cuenca hidrográfica del río Mira en Ecuador posee una alta biodiversidad, sin embargo, el uso intensivo del suelo ha ocasionado cambios en el paisaje y ha generado alteraciones en la distribución de especies. El presente estudio evalúa los patrones espaciales del paisaje boscoso y sus impactos en la distribución de Dipsas elegans (Boulenger, 1986) mediante mapas temáticos de uso y cobertura de suelo derivados de imágenes satelitales Landsat de los años 1991, 2000 y 2017, y la generación de métricas para la evaluación del paisaje boscoso. Adicionalmente, se analizó la distribución potencial de D. elegans usando el modelo de máxima entropía (MaxEnt). Los resultados obtenidos evidenciaron que existió una pérdida del bosque de 235.726,96 ha (10,28%) con una tasa de deforestación anual del 0,44%. Además, se registró un incremento del número de parches (1.249-1.741) y su densidad (0,23-0,33), lo que demuestra fragmentación del bosque nativo debido al avance del uso de suelo agrícola y la deforestación. D. elegans se distribuye principalmente en la cuenca media del río Mira, la cual registra la presencia de bosque nativo y otras coberturas con un área de 104.747 ha (19,6%). La pérdida de hábitat de D. elegans, respecto al modelo de distribución fue de 33.859,33 ha (32,32%), lo que demuestra que la especie es susceptible a la reducción del tamaño de parche, efectos borde y aislamiento de hábitat.