Climate change impacts on agriculture could arguably be most critical for developing countries in tropical regions: their populations rely importantly on agriculture and climate-dependant resources, poverty limits their capacity to anticipate and adapt to climate change, and population increase already poses a serious challenge to food security in those regions. Current projections of climate change impacts on tropical crop yields, even though on average negative, remain largely uncertain: there is need for more consistent, large-scale, quantitative assessments.

When attempting to address the environmental problems of a catchment, it is important to consider changes in a long-term environmental context. However, the long-term data on the state of the environment that are required for such an examination are rarely documented. Such data collection typically requires several years of investigation and observation. In addition, as there may be a significant time lag between the occurrence of a phenomenon and its cause, subsequent environmental investigations of changing animal and plant states scaling up to 5 years may be inadequate.

This special issue has presented some of the specific findings of the RE-Impact Project which was commissioned and funded by the EuropeAid Cooperation Office from 2007 until its conclusion in 2010. The project aimed to provide impact assessment frameworks and influence relevant policies through direct involvement in bioenergy projects and policy analysis in South Africa, Uganda, India and China. The papers summarised here have covered issues related to Jatropha curcas and forest-based bioenergy in these countries.

Legislative changes during the 1960s–1970s granted user rights over wildlife to landowners in southern Africa, resulting in a shift from livestock farming to wildlife-based land uses. Few comprehensive assessments of such land uses on private land in southern Africa have been conducted and the associated benefits are not always acknowledged by politicians. Nonetheless, wildlife-based land uses are growing in prevalence on private land. In Namibia wildlife-based land use occurs over c. 287,000 km².

Cities are characterized by dynamic interactions between socio-economic and biophysical forces. Currently more than half of the global population reside in cities which influence the global biogeochemical cycles and climate change, substantially exacerbating pressures on urban pollution, water quality and food security, as well as operating costs for infrastructure development. Goods and services such as aesthetic values, water purification, nutrient recycling, and biological diversity, that urban ecosystems generate for the society, are critical to sustain.

Population growth, urbanisation and climate change represent significant pressures on urban water resources, requiring water managers to consider a wider array of management options that account for economic, social and environmental factors.

Land cover changes affect local surface energy balances by changing the amount of solar energy reflected, the magnitude and duration over which absorbed energy is released as heat, and the amount of energy that is diverted to non-heating fluxes through evaporation. However, such local influences often are only crudely included in climate modeling exercises, if at all. A better understanding of local land conversion dynamics can serve to inform inputs for climate models and increase the role for land use planning in climate management policy.

This article reviews the level of current scientific understanding regarding the impact of future change in the large-scale climate-earth system on ecosystem services. Impacts from sea level rise, ocean acidification, increases in ocean temperature, potential collapse of the thermohaline circulation; failure of the South Asia monsoon; the melting of sea ice, the Greenland Ice Sheet and the West Antarctic Ice Sheet; changes in water availability; and Amazonia forest dieback, are considered.

Soil erosion by water is a major environmental threat to the sustainability and productive capacity of agriculture in many tropical and sub-tropical regions of the world. In temperate regions, meanwhile, the ‘off-site’ transport of sediment and pollutants into nearby water courses and the ‘muddy flooding’ of properties and infrastructure pose a much greater threat.

The conversion of marginal croplands to tree plantations, as an option to address climate change, land degradation, and irrigation water scarcity, as well as to improve the welfare of local population requires prior analysis.

Global changes in climate today present hostile weather conditions which pose considerable threats to the rich and poor alike. The capacity for developing countries to cope with these impacts is weak and a development concern. The post-conflict West African nation of Sierra Leone is no exception. In fact, rural areas are exposed to high degrees of vulnerability, livelihood insecurity and hostile environments. This paper explores the experiences of rural people and identifies impacts and coping mechanisms used in response to these changes.

This study provides a framework for the joint analysis of long-term land cover changes and climatic variations at regional scale. The land cover distribution observed in Italy in 1960, 1990, and 2006 was compared with trends in annual precipitation and the aridity index estimated during 1951–2007. Annual rainfall decreased by 0.41% per year during the examined period with the consequent increase in the aridity index (0.48% per year). Both rainfall decrease and aridity increase followed a non-uniform spatial distribution impacting differently the Mediterranean landscape mosaic.