Maintaining sustainable development in semi-arid regions is a complex task due to scarce precipitation, with notable temporal and spatial variations that complicate planning and proper management of water resources. Most of the water extractions from the aquifers in southeast Spain are carried out to supply a growing agricultural sector and increasingly successful tourism, which is the case of the Sierra de Gador-Campo de Dalias system. Savings, reutilization and awareness among water users are essential elements in any sustainable water policy. Some of the possible solutions proposed that offer low environmental impacts include certain infrastructure works, such as dams, ditches or recharge in gravel pits. Also, desalinization plants constitute a technical alternative in theory but involve high costs. The integration of all these resources, together with their proper management, is necessary to ensure the future water supply and economic growth in the region, safeguarding the state of its aquifers that are currently intensely overexploited.

Intensive irrigated agriculture substantially modifies the hydrological cycle and often has major environmental impacts. The article focuses upon a specific concern-the tendency for progressive long-term increases in the salinity of groundwater recharge derived from irrigated permeable soils and replenishment of unconfined aquifers in more arid regions. This process has received only scant attention in the water-resource literature and has not been considered by agricultural science. This work makes an original contribution by analysing, from scientific principles, how the salinisation of groundwater recharge arises and identifies the factors affecting its severity. If not proactively managed, the process eventually will impact irrigation waterwell salinity, the productivity of agriculture itself, and can even lead to land abandonment. The types of management measure required for mitigation are discussed through three detailed case histories of areas with high-value groundwater-irrigated agriculture (in Spain, Argentina and Pakistan), which provide a long-term perspective on the evolution of the problem over various decades.

The aim of the research detailed here has been to apply a new approach in assessing cave environmental changes -the so-called Cave Disturbance Index (CDI), relating to relief, water objects, air, vegetation and fauna (as the main geographical components of the cave environment) plus cultural aspects of recent cave use. Indicators coming under each of these categories are considered in detail and a quantitative estimation of total CDI then proposed. Practical application of the CDI method is then demonstrated by reference to caves situated in the Muradimovskoe Uschelie Natural Park (Southern Ural Mountains).

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Agricultural irrigation represents the main use of global water resources. Irrigation has an impact on the environment, and scientific evidence suggests that it inevitably leads to salinization of both soil and aquifers. The effects are most pronounced under arid and semi-arid conditions. In considering the varied impacts of irrigation practices on groundwater quality, these can be classed as either directthe direct result of applying water and accompanying agrochemicals to croplandor indirectthe effects of irrigation abstractions on groundwater hydrogeochemistry. This paper summarizes and illustrates through paradigmatic case studies the main impacts of irrigation practices on groundwater salinity. Typically, a diverse range of groundwater salinization processes operating concomitantly at different time scales (from days to hundreds of years) is involved in agricultural irrigation. Case studies suggest that the existing paradigm for irrigated agriculture of focusing mainly on crop production increases has contributed to widespread salinization of groundwater resources.