文章基本信息

标题：A Peri-Urban Neotropical Forest Transition and its Consequences for Environmental Services
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作者：H Ricardo Grau ; María Eugenia Hernández ; Jorgelina Gutierrez 等
期刊名称：Ecology and Society
印刷版ISSN：1708-3087
电子版ISSN：1708-3087
出版年度：2008
卷号：13
期号：1
出版社：The Resilience Alliance
摘要：We analyzed changes in land cover in the Sierra de San Javier and its surroundings, an area of ca. 70 000 ha near San Miguel de Tucumán, an urban center of ca. 1 million people in subtropical Argentina. The analysis covered two periods: 1949–1972 and 1972–2006 using remote sensing techniques. For the year 2001, we mapped the patterns of distribution of secondary forests dominated by the most abundant exotic tree species (Ligustrum lucidum). Based on land-cover maps, we estimated sediment yield as an index of watershed condition. Urban area was growing during the whole study period. Between 1949 and 2006, forest area increased approximately 1400 ha, mostly over abandoned agriculture and grasslands; this expansion was accelerated between 1972 and 2006. Increased forest cover resulted in a reduction in erosion and sediment yield that was disproportionately large, as most new forests are located in areas of steep slopes and high rainfall. By 2001, Ligustum-dominated forests had expanded to more than 500 ha, in the southern portion of the sierra only. Overall, the analysis quantifies a process of Neotropical peri-urban forest transition, likely associated with socioeconomic changes related to population urbanization, that promotes improvements of some environmental services, such as watershed and biodiversity conservation. However, natural communities are strongly affected by past land use and neighboring urban areas, which have promoted a growing importance of exotic species with mostly unknown ecological consequences.
关键词：exotic species invasion; forest transition; GIS; land-use change; subtropical Argentina; urbanization; watershed conservation; yungas