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Copyright of Kirkuk University Journal for Scientific Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) 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.)

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.)

Reforestation is very important in controlling land degradation and desertification. It has been established that the early diagnostics of the forest-growth conditions of soils and sustainability of forest plantations can be estimated by biogenic factors, such as the structure, dynamics, and functional activity of microbial complexes closely related to agrochemical soil indicators. The survival and sustainability of experimental forest plantations that were established in 1975 to 1978 on erosion-prone lands in the coastal zone of Shira Lake (Khakassia) have been studied. The forest growing properties of soils and the transformation of their fertility under the influence of stands have been evaluated. [ABSTRACT FROM AUTHOR]

Modern wars generate devastating effects on the environment by using chemical, biological, radioactive weapons. Toxic effects persist for long time on war fields. Negative environmental impacts such as desertification, migrant masses, depletion of natural resources (food, water, wood, etc.), and induced biodiversity produce, in turn, conflicts. This paper aims at i) identifying the consequences of conflicts and wars on the built environment with special reference to the industrial and residential buildings in urban areas; ii) determining the environmental impact of the procurement and use of natural resources and materials for the reconstruction of human settlements; iii) describing the results of this contribution according to their practical use. The research starts with a critical analysis of international examples related to modern wars. Contemporary situations of environmental degradation also related to major natural disasters that have altered the context in which they happened have been then analysed. Moreover, results of some significant interventions of environmental clean-up and building reconstruction have been examined, together with guidelines of the international humanitarian organizations on aspects of health and quality of life in areas with depleted environment. Results of these studies permit to suggest a post war methodology for the revitalization of the territory with restocking and monitored rebuilding, coordinated with contextual recovery of ecosystems. Construction techniques, with characteristics of resilience, habitability and sustainability are finally proposed. These solutions must also strive for reintegration of personal property and for the definitive localization of residents respecting their traditions and culture. Overall, this paper gives an operative contribution to one of the most important problems of humanity, which can be useful to future researches on territories marked by the environmental degradation caused by wars. Recovered environments, made sustainable, may help to understand that the real solution is avoiding wars and their deleterious effects. [ABSTRACT FROM AUTHOR]

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.)

Initial mapping of secondary succession in places disturbed by mining of the Khan Khentii Strictly Protected Area in Mongolia shows a possible innovative direction taken by afforestation in order to prevent further expansion of the Gobi Desert in northern Mongolia. The study results from the knowledge of secondary succession of mined areas, which are classified as the remains and consequences of prospecting and mining work dated to the Soviet times. Ongoing succession on sites affected by mining is very slow. In quarry dumps and canavas, herb layer has not been recovered despite the fact that the prospecting and mining activities had finished more than 30 years ago. Herbs biodiversity is very poor in these areas. Conversely, representatives of the tree layer, especially Larix sibirica and Populus tremula, are found far from the continuous forest; they colonized sites located within the aridized steppe. We assume that the main factor of successful tree growth on the mining activities remains consists in the humidity condensation due to and caused by the specific shape of the canavas and dumps. Trees prosperity on these extreme habitats can be ensured particularly in the early stages of growth when the tree roots are unable to reach the groundwater table. Detail mapping of quantitative and qualitative parameters of trees shows that the dump is an ideal shape of self-watering condensation mound for forest growth and can prevent the desertification as well. [ABSTRACT FROM AUTHOR]

Since the start of the Holocene, temperatures in the Arctic have steadily declined. This has been accredited to the orbitally forced decrease in summer insolation reconstructed over the same period. However, here we present climate modelling results from an Earth model of intermediate complexity (EMIC) that indicate that 17-40% of the cooling in the Arctic, over the period 9-0 ka, was a direct result of the desertification that occurred in the Sahara after the termination of the African Humid Period. We have performed a suite of sensitivity experiments to analyse the impact of different combinations of forcings, including various vegetation covers in the Sahara. Our simulations suggest that over the course of the Holocene, a strong increase in surface albedo in the Sahara as a result of desertification led to a regional increase in surface pressure, a weakening of the trade winds, the westerlies and the polar easterlies, which in turn reduced the meridional heat transported by the atmosphere to the Arctic. We conclude that during interglacials, the climate of the Northern Hemisphere is sensitive to changes in Sahara vegetation type. [ABSTRACT FROM AUTHOR]

Soil erosion is the most important factor in land degradation and influences desertification in semi-arid areas. A comprehensive methodology that integrates revised universal soil loss equation (RUSLE) model and GIS was adopted to determine the soil erosion risk (SER) in semi-arid Aseer region, Saudi Arabia. Geoenvironmental factors viz. rainfall (R), soil erodibility (K), slope (LS), cover management and practice factors were computed to determine their effects on average annual soil loss. The high potential soil erosion, resulting from high denuded slope, devoid of vegetation cover and high intensity rainfall, is located towards the north western part of the study area. The analysis is investigated that the SER over the vegetation cover including dense vegetation, sparse vegetation and bushes increases with the higher altitude and higher slope angle. The erosion maps generated with RUSLE integrated with GIS can serve as effective inputs in deriving strategies for land planning/management in the environmentally sensitive mountainous areas. [ABSTRACT FROM AUTHOR]

Arid and semiarid China have experienced multiple arid phases throughout the Quaternary, and over the past five decades, there have been several periods with relatively high or low rates of desertification and rehabilitation. The causes of these changes and their historical trends have been debated by scientists because of their potentially huge significance for China, as well as for the global ecology and food supply. This paper reviews recent studies of desertification in different regions of arid and semiarid China. In general, the results of systematic monitoring, and analyses of the causes of desertification and the contemporaneous human impacts, suggest that desertification in China has been primarily caused by climate change, and particularly by strong wind regimes (with high sand transport potential) accompanied by decreased spring precipitation. Unfortunately, although numerous scientists have claimed that desertification in China is primarily due to human impacts: there is surprisingly little unassailable evidence to support this claim. The review presented in this paper show that desertification in China is likely to be controlled by climate change and geomorphological processes, even though human impacts have undeniably exacerbated their effects. Our arguments for both climate change and human activity as factors responsible for the observed changes in desertification rely primarily on inferences based on correlations between trends, thus future research must seek stronger and more direct evidence for the causal relationships that we have proposed as possibilities. This improved information is essential to provide a firm basis for future policy decisions on how best to combat desertification.

Carbonate rocks distribute widely in China. The total area of the carbonate rocks is about 3,430,000 km, and the exposed area of the carbonate is approximately 13 % of China's territory. In 2003, soil loss in Yunnan, Guizhou, and Guangxi provinces reached 179,600 km, which is almost 40.1 % of the total area, causing rocky desertification. In this study, the erosion-creep-collapse mechanism of underground soil loss for the karst rocky desertification in Chenqi village, Puding county, Guizhou province is proposed. The mechanism occurs under the following geological environment: slope surface undulation, underlying bedrock surface fluctuation and thin and inhomogeneous soil overlying, overlying soil generation by bedrock weathering, underground karst development, and large groundwater depth and lying water table under the bottom of soils. The erosion-creep-collapse mechanism of underground soil loss in the karst slopes is explained as follows: power loss due to human cultivation activities that destroy the soil structure, hydraulic force formed by rainfall infiltration, wet-dry cycle generated by rainfall, erosion effect caused by rainfall penetration, creeping and flowing of plastic-stream soil, and collapse. The erosion-creep-collapse mechanism of underground soil loss has seven steps: disturbance of soils filled in underground karst cave by human activities, internal soil erosion and partial collapse caused by hydraulic power, internal free surface formation within the soil in the filled karst cave, internal soil creeping, soil pipe formation, soil pipe collapse, and ground surface collapse and filling. Soil loss develops slowly, and sudden transportation occurs by collapse. Soil loss can be explained by the proposed mechanism, and soil loss can be prevented by controlling soil collapse. [ABSTRACT FROM AUTHOR]

The article discusses the role of the Pan-African Parliamentarians' Network on Climate Change (PAPNCC) in the desertification of lands because of climate change. Topics mentioned include the definitions of desertication and climate change, the link between the two and the concrete actions of PAPNCC to fight climate change and Africa desertification. It mentioned the missions of PAPNCC which includes influencing decisions, laws and public opinions, building awareness, and denouncing damages.

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]

Quantitative information on the contribution of dust storms to atmospheric PM10(particulate matter with an aerodynamic diameter ≤10 µm) levels is still lacking, especially in urban environments with close proximity to dust sources. The main objective of this study was to quantify the contribution of dust storms to PM10concentrations in a desert urban center, the city of Beer-Sheva, Negev, Israel, during the period of 2001–2012. Toward this end, a background value based on the “dust-free” season was used as a threshold value to identify potentially “dust days.” Subsequently, the net contribution of dust storms to PM10was assessed. During the study period, daily PM10concentrations ranged from 6 to over 2000 µg/m3. In each year, over 10% of the daily concentrations exceeded the calculated threshold (BVt) of 71 µg/m3. An average daily net contribution of dust to PM10of 122 µg/m3was calculated for the entire study period based on this background value. Furthermore, a dust storm intensity parameter (Ai) was used to analyze several storms with very high PM10contributions (hourly averages of 1000–5197 μg/m3). This analysis revealed that the strongest storms occurred mainly in the last 3 yr of the study. Finally, these findings indicate that this arid urban environment experiences high PM10levels whose origin lies in both local and regional dust events. [ABSTRACT FROM PUBLISHER]

The authors explore a new approach to monitoring of desertification that is based on use of results on the relation between albedo and surface temperature for the Sonoran Desert in northwestern Mexico. The criteria of predominance of radiation by using the threshold value of Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectroradiometer (MODIS) normalized difference vegetation index (NDVI) were determined. The radiation mechanism for regulating the temperature of the surface and the definition of threshold values for AVHRR and MODIS NDVI have an objective justification for the energy budget, which is based on the dominance of radiation surface temperature regulation in relation to evapotranspiration. Changes in the extent of arid regions with AVHRR NDVI of <0.08 and MODIS NDVI of <0.10 can be considered to be a characteristic in the evolution of desertification in the Sonoran Desert region. This is true because, in a certain year, the time span of the period when radiation factor predominates is important for the desertification process. [ABSTRACT FROM AUTHOR]

An assessment is presented on land degradation and its impact on food security, or food supply reliability. Preventive measures include decentralizing the management of sustainable development programs, and to strengthen international agreements regarding land use.

Desertification, land degradation in arid, semi-arid, and dry sub-humid regions, is a global environmental problem. With respect to increasing importance of desertification and its complexity, the necessity of attention to the optimal de-desertification alternatives is essential. Therefore, this work presents an analytic hierarchy process (AHP) method to objectively select the optimal de-desertification alternatives based on the results of interviews with experts in Khezr Abad region, central Iran as the case study. This model was used in Yazd Khezr Abad region to evaluate the efficiency in presentation of better alternatives related to personal and environmental situations. Obtained results indicate that the criterion 'proportion and adaptation to the environment' with the weighted average of 33.6% is the most important criterion from experts viewpoints. While prevention alternatives of land usage unsuitable of reveres and conversion with 22.88% mean weight and vegetation cover development and reclamation with 21.9% mean weight are recognized ordinarily as the most important de-desertification alternatives in region. Finally, sensitivity analysis is performed in detail by varying the objective factor decision weight, the priority weight of subjective factors, and the gain factors. After the fulfillment of sensitivity analysis and determination of the most sensitive criteria and alternatives, the former classification and ranking of alternatives does not change so much, and it was observed that unsuitable land use alternative with the preference degree of 22.7% was still in the first order of priority. The final priority of livestock grazing control alternative was replaced with the alternative of modification of ground water harvesting. [ABSTRACT FROM AUTHOR]

Abstract: Based on extraction of environmental information from lake (reservoir) sediment, this paper carried out systematic studies on effects of land use/land cover changes on soil erosion in last 40 years in Shibanqiao catchment of Guanling County, located in the southwest of Guizhou Province. Seven sediment cores were retrieved and analysis of activity of 137Cs of sediment samples was undertaken. The information of soil erosion in each phase was deduced, and then integrating it with land use/land cover changes in corresponded phase, the author took a further step to interpret the effects of land use/land cover changes on soil erosion. Such conclusions were drawn: (1) the rate and amount of soil erosion is related not only with land use/land cover regime but also with whether there are abundant erodible sources provided for erosion. (2) During 1960 to 1978, in the beginning of land use change, naturally selective erosion was dominant. Then the percentage of surface soil erosion increased, and became dominant in the subsequent phase. Soil erosion was decreased but rocky desertification expanded in a higher rate. So it can be deduced that there was a lag between the development of rocky desertification and soil erosion;(4) The accelerated soil erosion resulted from the stir of soil during the implementation of ecological engineering was detected between 1990 to 2002, in view of which, a suggestion was put forward in this paper that ecological constructions and engineering towards water and soil maintenance should pay attention to the problem of soil erosion followed, especially should avoid the stir of soil. © 2011 Published by Elsevier Ltd. Selection and peer-review under responsibility of RIUDS [Copyright &y& Elsevier]

Steppe grasslands are distributed over vast areas in arid and semiarid regions of Eurasia. However, steppe grasslands face desertification or degradation caused by human over-activity. In the last decades, steppe regions have seen increased areas of crop cultivation and subsequent abandonment due to inappropriate agricultural management. Land degradation of abandoned croplands has become a common problem in the Inner Mongolia Autonomous Region, China. A field survey was conducted in the Xilingol steppe, and vegetation was classified into three groups. Based on comparisons of species composition and soil characters, group 1 represents steppe grassland, group 2 represents abandoned croplands and group 3 represents yardangs. The typical indicator species of steppe, abandoned croplands and yardangs are Leymus chinensis, Cleistogenes squarrosa and Elymus dahuricus, respectively. Abandoned croplands are exposed to wind and rain, resulting in soil erosion, which not only increases coarse sand content but also decreases total carbon and total nitrogen in the soil. We found that soil condition is an important factor affecting the early stages of secondary succession in abandoned croplands and that farming in typical steppes might contribute to land degradation. We concluded that abandoned croplands can be converted to yardangs by erosion. The extension of yardangs might then lead to desertification in steppe regions. Land managers should be aware that farming in typical steppes is associated with a risk of desertification. The degree of degradation of steppe can be measured by monitoring these indicator species. [ABSTRACT FROM AUTHOR]

Desertification is of critical concern because it may affect 40% of the global land area inhabited by more than 1 billion people. During the process of desertification, defined as land degradation in arid, semi-arid and dry subhumid areas, drylands shift to a state of reduced biological productivity that may lead to widespread loss of human well-being. Despite recent advances, we need a better understanding of the response of ecosystems to desertification to improve the assessment and monitoring of desertification. We used a published physiognomic description, MODIS monthly NDVI data for 2000-2005 and rain gauge data to characterize the long-term effects of degradation for an area of 128 000 ha located in western Patagonia. We focused on three aspects of vegetation dynamics: radiation interception, precipitation use efficiency (PUE) and the sensitivity of vegetation to interannual changes in precipitation (i.e. the slope of the relationship between the above-ground net primary productivity and precipitation, the precipitation marginal response, PMR). In particular, we analysed the response of PMR and PUE to long-term changes in vegetation structure due to grazing. On average, NDVI decreased by 28%, ranging between 35% (grass or grass-shrub steppes to semi-deserts) and 22% (grass or grass-shrub steppes to low cover grass steppes) suggesting that, in Patagonia, desertification may imply a reduction in the above-ground net primary productivity. Additionally, PMR and PUE captured the functional modifications associated with vegetation structure caused by desertification. In general, grass and grass-shrub steppes had the highest average PUE and PMR. Shrub steppes and semi-deserts had the lowest PMR and PUE. These results support the hypothesis that PUE is more sensitive to changes in total plant cover and PMR to changes in plant functional type composition. Synthesis and applications. Our results indicate that the precipitation marginal response could complement current desertification assessments based only on precipitation use efficiency thereby improving our ability to monitor desertification. Enhanced monitoring programmes could provide an early warning signal for the onset of desertification allowing for timely management action. [ABSTRACT FROM AUTHOR]

The survival of the world's human populations in anything resembling their present numbers is unlikely. A number of interacting problems threaten future and present generations. The principal elements are continued population increase, accelerating adverse climatic change and all its consequences -especially increasing desertification, freshwater depletion, damaging climatic behaviour, crop damage, rising sea levels, and resource depletion. These events will probably accelerate attempts to migrate by ever larger numbers of people accompanied by civil and perhaps international conflict. The present fast evolving economic chaos is merely a precursor. This paper sketches the primary elements and postulates some grim possible consequences. [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 focuses on the water utilization of natural and planted trees in the semiarid desert. It mentions the application of stable isotope techniques to examine the water utilization of Sabina vulgaris Ant., Artemisia ordosic Krasch. and Salix Matsudana Koidz. in the semiarid desert of Inner Mongolia, China. It notes the decline of agricultural productivity due to severe desertification.

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.

The increase in desertification has caused concern among environmentalists and members of international organizations such as the UN. Reports indicate that desertification continues to spread in parts of Africa, South America and Asia. Scientists believe that human activity and interaction with the environment is the chief cause for the increase in global desertification. In order to halt the spread of desertification, interantional organizations such as the UN should reorient their programs and examine the social dynamics involved in the problem.

A primitive equations global zonally averaged climate model is developed. The model includes biofeedback mechanisms. For the Northern Hemisphere the parameterization of biofeedback mechanisms is similar to that used by Gutman et al. (1984). For the Southern Hemisphere new parameterizations are derived. The model simulates reasonably well the mean annual zonally averaged climate and geobotanic zones. Deforestation, desertification and irrigation experiments are performed. In the case of deforestation and desertification there is a reduction in the surface net radiation, evaporation and precipitation and an increase in the surface temperature. In the case of irrigation experiment opposite changes occurred. In all the cases considered the changes in evapotranspiration overcome the effect of surface albedo modification. In all the experiments changes are smaller in the Southern Hemisphere.

Outlines contributing factors affecting the rate of acceleration of land-degradation and desertification. Effects of natural causes to rate of desertification; Impact of negative resource management systems; Human factors contributing to desertification problem; Impact of desertification to socioeconomic status of population; Need for sustainable development strategies in development agenda.

Reports on the possibility that desertification is the result of inherent biophysical feedbacks in dryland systems. Application of the qualitative stability analysis of partially-specified systems; Seven key environmental components in desertification; Stability theory; Mutually-reinforcing links causing one variable to be favored.

The article presents several approaches that can be implemented to stop the desertification of the karst mountain region of Southwest China, which is extremely fragile geological environment and poor social economy. Population growth control is shown to be one of the major factors that can be used for the antidesertification and development of the region.

Several analyses are conducted to explain the various effects of the droughts and land desertification practices on the Agricultural Drought Framework, which is observed in the semiarid East African regions. It is shown that an increase in the usage of rainwater can be extremely beneficial, as it can lead to better productivity and food security in the country.

Desserts in China are expanding at an alarming rate due to overgrazing, water and agriculture mismanagement and the amplifying effects of climate change. Enterprising locals have turned to tourism as the desserts are taking over farmland.

The Heihe River Basin is a typical bigger inland river basin in the arid zone of Northwestern China but the changes in hydrological status and the degradation of vegetation have promoted land desertification and soil salinization in the entire middle and lower reaches of Heihe River Basin. The hydrological indicators of desertification in the Heihe River Basin are determined in both surface and ground water.

The change in mobility patterns with the onset of the desert is investigated through strontium isotope analysis of Holocene human skeletons from prehistorically burials in Fezzes in southwestern Libya with the aim of characterizing ancient groups' adaptations during progressive desertification. It is evident that the transformation in the economy of prehistoric groups correlated with a shift in mobility and kinship systems and the onset of the desert would have changed not only the way people approached local resources but also they way they perceived and organized themselves.

Protection policies such as returning farmland to forestry and pasture, conserving water, prohibition of grazing, and migration of farmers are the primary principles for regulating eco-environment degeneration in desertification areas of Northern China. However, conflicts have arisen between the policies implemented and the reality of eco-environmental protection, leading to an unchanged situation in the degeneration of the land.

Evaluates desertification through biological and environmental conditions. Correlations between excessive population growth and soil degradation; Effect of human pressure, drought and famine to the degradation cycle.