Land use change resulted in land degradation is a focus of research on global environmental changes and plays a significant role in the stability and economic development of oases in arid regions of China. Jinta Oasis, a typical oasis of temperate arid zone in northwestern China, was investigated to assess land-use change dynamics during 1988-2003 with the aid of satellite remote sensing and GIS, and to explore the interaction between these changes and oasis environment.

A dráguló olajár „felszínre hozta” a fosszilis energiahordozók környezetbarát energiahordozókkal való kiváltásának problémáját. Az olajkészletek korlátozottságamellett a bizonytalan kitermelés és a folyamatosan növekvő árak a bioüzemanyagokfelé irányítják a politikai döntéshozók és a befektetők figyelmét.

Water demand in a viable economy tends to be dynamic: it changes over time in response to growth, drought, and social policy. Institutional capacity to re-allocate water between users and uses under stress from multiple sources is a key concern. Climate change threatens to add to those stresses in snowmelt systems by changing the timing of runoff and possibly increasing the severity and duration of drought. This article examines Snake and Klamath River institutions for their ability to resolve conflict induced by demand growth, drought, and environmental constraints on water use.

Effects of salinity and sodicity on some soil physical properties were discussed in this article. Effects of salinity and sodicity on floculation, dispersion, infiltration, hydraulic conductivity, runoff and seal formation were taken into consideration in assessment. In many studies it is indicated that high natrium concentration of soil decreases infiltration and hydraulic conductivity values and stimulates crust formation and dispersion occurrence associated with many factors such as texture, structure, Ca and Mg concentration in solution.

In certain regions where mixed farming prevails, the specialization of the farms (with the progressive disappearance of livestock) has brought about uniform methods of land occupation which run counter the environmental functions of farming. For that matter, grasslands and perennial covers have beneficial effects, but their insertion or their maintenance have to be thought out at the territorial scale.

As data sets of multiple types and scales proliferate, it will be increasingly important to be able to flexibly combine them in ways that retain relevant information. A case in point is Amazonia, a large, data-poor region where most whole-basin data sets are limited to understanding land cover interpreted through a variety of remote sensing techniques and sensors. A growing body of work, however, indicates that the future state of much of Amazonia depends on the land use to which converted areas are put, but land use in the tropics is difficult to assess from remotely sensed data alone.

China has long been experiencing intense land use/cover changes (LUCC). Undesirable land use/cover changes have resulted in widespread land degradation. This study examines the temporal and spatial dynamics of land use change and land degradation as evident from land use survey datasets (1991-2001). Six prominent land degradation processes were identified, namely: desertification, secondary salinisation, loss of agricultural use, deforestation, grassland degradation and loss of wetland. Rates of conversion were calculated and distribution patterns were mapped with the aid of GIS.