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Effects of Land Cover Disturbance on Stream Invertebrate Diversity and Metal Concentrations in a Small Urban Industrial Watershed

Journal Articles & Books
Décembre, 2012

The landscape surrounding Sudbury, Ontario, has been severely affected by 100 years of mining and forestry and a recent, large-scale ecological risk assessment found that terrestrial plant communities continue to be impaired by remnant metals and poor soil conditions. We investigated the risks of these adverse landscape conditions on a small headwater stream by digitizing land cover at a fine scale and relating it to benthic invertebrate diversity and metal concentrations at 13 sites in the system.

Mapping land-use and land-cover change along Bolivia's Corredor Bioceánico with CBERS and the Landsat series: 1975–2008

Journal Articles & Books
Décembre, 2012
Bolivie
Amérique centrale
Amérique du Sud

This study uses a combination of Landsat series data (Multispectral Scanner or MSS, Thematic Mapper or TM and Enhanced Thematic Mapper or ETM+) to map land-use and land-cover change (LULCC) from 1975 to 2001. It extends the land change record to 2008 using Chinese–Brazil Earth Resources Satellite (CBERS)-2 and CBERS-2B data on a multi-scene level. It also establishes a methodology to correct for systematic distortion inherent in CBERS imagery without the loss of information present in Landsat 7 ETM+ imagery post-2003.

Accounting for space and time in soil carbon dynamics in timbered rangelands

Journal Articles & Books
Décembre, 2012

Employing rangelands for climate change mitigation is hindered by conflicting reports on the direction and magnitude of change in soil organic carbon (ΔSOC) following changes in woody cover. Publications on woody thickening and deforestation, which had led to uncertainty in ΔSOC, were re-evaluated, and the dimensional-dependence of their data was determined. To model the fundamentals of SOC flux, linked SOC pools were simulated with first-order kinetics. Influences from forest development timelines and location of mature trees, with a potential for deep-set roots, were considered.

Deforestation, agroforestry, and sustainable land management practices among the Classic period Maya

Journal Articles & Books
Décembre, 2012
Honduras

This article explores evidence of deforestation and forest management practices in the Maya lowlands during the pre-Columbian period. In the early twentieth century, scholars first began to examine the role of the environment in the rise and collapse of the great southern Maya polities of the Classic period, proposing that deforestation was an important factor in their political fragmentation and depopulation between the eighth and tenth centuries. In the last twenty-five years, this hypothesis has gained broad acceptance largely due to research at the ancient city of Copan, Honduras.

Multiple environmental services as an opportunity for watershed restoration

Journal Articles & Books
Décembre, 2012
Australie

The impact of reforestation on water supplies is often considered in terms of impacts on water yields. In specific circumstances, reforestation will improve water quality, to the extent that previously unusable water can be utilised. Such is the case with salinisation, a process that threatens up to 17million hectares of Australian farmland, major fresh water resources, biodiversity and built infrastructure.

Degradation of soils as a result of long-term human-induced transformation of the environment in Iran: an overview

Journal Articles & Books
Décembre, 2012
Iran

Human-induced soil degradation is a serious and complex environmental challenge in Iran. For a long time, human activities, namely the overuse of land, have been influencing the natural processes on and in soils; therefore, various types of soil degradation can be observed in many parts of the country. The understanding and the consideration of direct and indirect effects of human activities on soils are indispensable for the prediction of the human impact on soil degradation processes.

Can active restoration of tropical rainforest rescue biodiversity? A case with bird community indicators

Journal Articles & Books
Décembre, 2012

There is vigorous debate about the potential for reforestation to offset losses in biodiversity associated with tropical deforestation, but a scarcity of good data. We quantified developmental trajectories following active restoration (replanting) of deforested pasture land to tropical Australian rainforest, using 20 different bird community indicators within chronosequences of multiple sites. Bird species composition in restored sites (1–24years old) was intermediate between that of reference sites in pasture and primary rainforest.

Ecosystem functional changes associated with land clearing in NW Argentina

Journal Articles & Books
Décembre, 2012
Argentine

We assessed the extension of natural habitat conversion into croplands and grazing lands in subtropical NW Argentina and its impact on two key ecosystem functional attributes. We quantified changes in remotely sensed surrogates of aboveground net primary production (ANPP) and seasonality of carbon gains. Both functional attributes are associated with intermediate ecosystem services sensuFisher et al. (2009). Deforestation was estimated based on photointerpretation of Landsat imagery.

Global forecasts of urban expansion to 2030 and direct impacts on biodiversity and carbon pools

Journal Articles & Books
Décembre, 2012
Sri Lanka
Afrique occidentale
Global

Urban land-cover change threatens biodiversity and affects ecosystem productivity through loss of habitat, biomass, and carbon storage. However, despite projections that world urban populations will increase to nearly 5 billion by 2030, little is known about future locations, magnitudes, and rates of urban expansion. Here we develop spatially explicit probabilistic forecasts of global urban land-cover change and explore the direct impacts on biodiversity hotspots and tropical carbon biomass.

Committed carbon emissions, deforestation, and community land conversion from oil palm plantation expansion in West Kalimantan, Indonesia

Journal Articles & Books
Décembre, 2012
Indonésie

Industrial agricultural plantations are a rapidly increasing yet largely unmeasured source of tropical land cover change. Here, we evaluate impacts of oil palm plantation development on land cover, carbon flux, and agrarian community lands in West Kalimantan, Indonesian Borneo. With a spatially explicit land change/carbon bookkeeping model, parameterized using high-resolution satellite time series and informed by socioeconomic surveys, we assess previous and project future plantation expansion under five scenarios.

Comprehensive evaluation of the climate-change implications of shifting land use between forest and grassland: New Zealand as a case study

Journal Articles & Books
Décembre, 2012
Nouvelle-Zélande

The transition of land between forest and grassland has important implications for greenhouse gas emissions and removals. In this paper, we use New Zealand as a case study to comprehensively assess, compare and quantify the net climate change impact of shifting land use between temperate forest and grassland. Forests store large amounts of carbon in their biomass, whereas grasslands contain relatively little biomass carbon. These biomass changes tend to dominate the carbon balance under land-use change.

Impacts of internal and external policies on land change in Uruguay, 2001–2009

Journal Articles & Books
Décembre, 2012
Uruguay
Argentine

Policies play a pivotal role in determining land change. Uruguay has been subject to first a rise and then decline in plantations of exotic trees as a result of internal Uruguayan government policies, and a recent substantial increase in soybean cultivation that may be attributed to Argentinean policies. To properly assess the relationship between land change and changes in land-use policies, vegetation change for Uruguay from 2001 to 2009 was mapped using MODIS imagery.