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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The term of “desertification” refers to a land degradation processes of arid, semiarid and sub-humid areas. Although the concept originates from Sub-Saharan Africa, desertification threatens also the area of Hungary. The greatest desertification risk is in the central part of the country, in the Danube-Tisza Interfluve where drought has always been a huge problem for the local society. Aridification processes are mainly due to climate change. Temperature increase and precipitation decrease as well as the increase of the frequency and amplitude of extreme events contribute to the acceleration of desertification risk. Severe or moderate droughts occur in Hungary nearly every year. Drought frequency has increased, primarily in the last decades. Main findings of several research projects of MEDALUS II and III EU Framework projects (experiments on the effects of climate change on vegetation, soils and ground water level) are summarized in the paper. [ABSTRACT FROM AUTHOR]

Copyright of Zagazig Journal of Agricultural Research is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dealing with major risks has become one of the most important challenges for sustainable urban development in the light of rapid urbanization, which touched most of Algerian cities and led to a doubling of human, material, economic and environmental losses, which in turn led to the deterioration of the urban fabric. Since the early 1960s the city of Bou Saada underwent a fast, chaotic and unplanned urban evolution over 65% of its surface, most of which is located on slopes - slopes of mountains, of valleys - and near the sand dunes, being thus exposed to the risk of flooding, rockfalls and desertification. A morpho-dynamic analysis shows that this is linked to the physical environment on the one hand and, on the other hand, human activities like rapid population growth in urban areas, the ambiguity of the real estate Algerian slums and the various irresponsible types of configuration carved these dangers and increased their severity in the urban system. In order to reduce their harm, these natural hazards must be understood, their impact on the urban area determined and the urban agglomerations must be protected from their effects. [ABSTRACT FROM AUTHOR]

There has been dam building in Iran since Achaemenian times (2500 years ago) as a means to control water streams. While dam building was stopped for a time, other indigenous approaches to water management, such as qanats (known for more than 3,000 years), surface ponds and underground small ponds for rain harvesting have been continuously used by farmers to date. The new era of dam building was begun in Iran in the mid 1950s by international companies and has since remained the major approach to water supply. Yet dam building has affected the quantity and quality of water in watersheds, rivers and other water bodies, leading to noticeable destruction of natural habitats and species. Dam building has inundated forests in reservoirs, helped in timber smuggling upstream, and decreased forests downstream, thus accelerating desertification. The actual benefits of dams do not offset even a part of the costs incurred for construction, and their operation and maintenance. [ABSTRACT FROM AUTHOR]

Arid and semiarid regions cover more than 40% of Earth's land surface. Desertification, or broadscale land degradation in drylands, is a major environmental hazard facing inhabitants of the world's deserts as well as an important component of global change. There is no unifying framework that simply and effectively explains different forms of desertification. In this article, we argue for the unifying concept that diverse forms of desertification, and its remediation, are driven by changes in the length of connected pathways for the movement of fire, water, and soil resources. Biophysical feedbacks increase the length of connected pathways, explaining the persistence of desertified landscapes around the globe. Management of connectivity in the context of environmental and socioeconomic change is essential to understanding, and potentially reversing, the harmful effects of desertification. [ABSTRACT FROM AUTHOR]

The article discusses the expansion of shrubs and the reduction of herbaceous species in California. It examines the presence of gopher disturbance in the reproduction of sagebrush plants along with the availability of water. It also cites the growth and survival of the sagebrush seedlings based on the climatic and soil conditions of the ecosystem.