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Cao H.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Cao H.,University of Chinese Academy of Sciences | Liu J.,International Ecosystem Management Partnership | Wang G.,CAS Institute of Remote Sensing | And 4 more authors.
Journal of Arid Land | Year: 2015

Sand and dust storms (SDS) are common phenomena in arid and semi-arid areas. In recent years, SDS frequencies and intensities have increased significantly in Iran. A research on SDS sources is important for understanding the mechanisms of dust generation and assessing its socio-economic and environmental impacts. In this paper, we developed a new approach to identify SDS source areas in Iran using a combination of nine related datasets, namely drought events, temperature, precipitation, location of sandy soils, SDS frequency, human- induced soil degradation (HISD), human influence index (HII), rain use efficiency (RUE) and net primary productivity (NPP) loss. To identify SDS source areas, we firstly normalized these datasets under uniform criteria including layer reprojection using Lambert conformal conic projection, data conversion from shapefile to raster, Min-Max Normalization with data range from 0 to 1, and data interpolation by Kriging and images resampling (resolution of 1 km). After that, a score map for the possibility of SDS sources was generated through overlaying multiple datasets under average weight allocation criterion, in which each item obtained weight equally. In the score map, the higher the score, the more possible a specific area could be regarded as SDS source area. Exceptions mostly came from large cities, like Tehran and Isfahan. As a result, final SDS source areas were mapped out, and Al-Howizeh/Al-Azim marshes and Sistan Basin were identified as main SDS source areas in Iran. The SDS source area in Al-Howizeh/Al-Azim marshes still keeps expanding. In addition, Al-Howizeh/Al-Azim marshes are now suffering rapid land degradation due to natural and human-induced factors and might totally vanish in the near future. Sistan Basin also demonstrates the impacts of soil degradation and wind erosion. With appropriate intensity, duration, wind speed and altitude of the dust storms, sand particles uplifting from this area might have developed into extreme dust storms, especially during the summer. © Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Science Press and Springer-Verlag Berlin Heidelberg 2015.

Cao H.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Cao H.,University of Chinese Academy of Sciences | Amiraslani F.,University of Tehran | Liu J.,International Ecosystem Management Partnership | And 2 more authors.
Science of the Total Environment | Year: 2015

Sand and Dust storms are common phenomena in arid and semi-arid areas. West Asia Region, especially Tigris-Euphrates alluvial plain, has been recognized as one of the most important dust source areas in the world. In this paper, a method is applied to extract SDS (Sand and Dust Storms) sources in West Asia region using thematic maps, climate and geography, HYSPLIT model and satellite images. Out of 50 dust storms happened during 2000-2013 and collected in form of MODIS images, 27 events were incorporated as demonstrations of the simulated trajectories by HYSPLIT model. Besides, a dataset of the newly released Landsat images was used as base-map for the interpretation of SDS source regions. As a result, six main clusters were recognized as dust source areas. Of which, 3 clusters situated in Tigris-Euphrates plain were identified as severe SDS sources (including 70% dust storms in this research). Another cluster in Sistan plain is also a potential source area. This approach also confirmed six main paths causing dust storms. These paths are driven by the climate system including Siberian and Polar anticyclones, monsoon from Indian Subcontinent and depression from north of Africa. The identification of SDS source areas and paths will improve our understandings on the mechanisms and impacts of dust storms on socio-economy and environment of the region. © 2014 Elsevier B.V.

Avishek K.,International Ecosystem Management Partnership | Avishek K.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Yu X.,International Ecosystem Management Partnership | Yu X.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Liu J.,International Ecosystem Management Partnership
Environmental Development | Year: 2012

Ecosystem complexities and the science-policy gap contribute to the challenges of ecosystem management. The objective of the paper is to assess selected existing ecosystem management policies, identify the science-policy gaps, and suggest measures for bridging the gaps for ecosystem management (EM) in Asia Pacific region. Nearly 18% of the world's total forest cover is found in the Asia Pacific region. Cropland has expanded by 130,000. sq km over the last 20 years at the expense of grasslands and forests that are the home to major biodiversity. Ecosystems such as forests, grasslands and mangroves have partially recovered from degradation in emerging economies like China, India, and Malaysia. This study shows that research on driving forces, fragile ecosystems, and appropriate policies need to be strengthened. Inadequate capacities and lack of strategies for community participation further broadens the science-policy gap. To bridge the gap, the following recommendations are proposed:. i)Encouraging policy oriented research in universities and research organization.ii)Developing research on fragile ecosystems.iii)Supporting capacity building and research in developing nations.iv)Developing strategies for community participation. It is further suggested that Australia, Japan, Republic of Korea, China, India and Malaysia act as referral countries for promoting ecosystem management practices in and across the region. Key research organizations from these countries could act as reference points for developing nations. Success stories from developed and emerging economies can also help in improving the region's research capabilities, policy orientations, and capacities. © 2012 Elsevier B.V.

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