A landscape ecology assessment of land-use change on the Great Plains-Denver (CO, USA) metropolitan edge

For better or worse, in those parts of the world with a widespread farming, livestock rising, and urban expansion, the maintenance of species richness and ecosystem services cannot depend only upon protected natural sites. Can they rely on a network of cultural landscapes endowed with their own associated biodiversity? We analyze the effects of land-cover change on landscape ecological patterns and processes that sustain bird species richness associated to cropland-grassland landscapes in the Great Plains-Denver metropolitan edge. Our purpose is to assess the potential contribution to bird biodiversity maintenance of Great Plain's cropland-grassland mosaics kept as farmland green belts in the edge of metropolitan areas. We present a quantitative landscape ecology assessment of land-cover changes (1930-2010) experienced in five Great Plains counties in Colorado. Several landscape metrics assess the diversity of land-cover patterns and their impact on ecological connectivity indices. These metrics are applied to historical land-cover maps and datasets drawn from aerial photos and satellite imagery. The results show that the cropland-grassland mosaics that link the metropolitan edge with the surrounding habitats sheltered in less human-disturbed areas provide a heterogeneous land matrix were a high bird species richness exists. They also suggest that keeping multifunctional farmland-grassland green belts near the edge of metropolitan areas may provide important ecosystem services, supplementing traditional conservation policies. Our maps and indicators can be used for selecting certain types of landscape patterns and priority areas on which biodiversity conservation efforts and land-use planning can concentrate

Introduction: historical perspectives on bioinvasions in the Mediterranean region

This chapter introduces the main themes of the book and states its aims and scope. It defines and provides an overview of the study region, discussing the biophysical and historiographical dimensions of defining a ‘Mediterranean region’. Key polemics arising in debates over how to think about bioinvasions are considered, and the editors’ positions clarified. An overview of the book’s ten chapters follows, informing a concluding discussion on directions for future study of bioinvasions in the Mediterranean region

Domesticated Nature : The Culturally Constructed Niche of Humanity

William Denevan argued that pristine landscapes are a myth, including in Amazonia-imagined by many as one of the last bastions of pristine Nature. During the last century, evidence accumulated to show that humans domesticated Nature during the Holocene by creating cultural niches in all habitable regions of the planet. This process of cultural niche construction is the result of human agency, grounded on culturally transmitted ecological knowledge to domesticate landscapes, and plant and animal populations, thus increasing human carrying capacity. The expansion of culturally constructed niches during the Holocene does not mean that every inch of the habitable planet became a garden; rather, there is a mosaic of landscapes domesticated to different degrees, especially forests. Consequently, domesticated landscapes depend upon their humans, even though humans can also degrade these landscapes, which gave rise to the Anthropocene concept. As a result, Edward O. Wilson proposed that half of the biosphere be set aside for Nature. Many prime areas for the half-Earth proposal are tropical forests, all with high linguistic diversity; Borneo, New Guinea, the Congo, and Amazonia are examples. Since all of Nature in the habitable regions of the planet is cultural to some degree, setting aside half requires partnership with local human populations, rather than their exclusion, which is too common today. Their participation is essential, because it is their niche construction activities that resulted in what we call Nature and without them Nature will change-through natural processes-into something different from that which we plan to conserve