Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Master → Chine → 2015 → Research on the Climatic Characteristics and Factors of Sand Emission Index as Well as Its Environmental Effects in the North of China

Lanzhou University (2015)

Research on the Climatic Characteristics and Factors of Sand Emission Index as Well as Its Environmental Effects in the North of China

付洁

Titre : Research on the Climatic Characteristics and Factors of Sand Emission Index as Well as Its Environmental Effects in the North of China

Auteur : 付洁

Grade : Master’s Theses 2015

Université : Lanzhou University

Résumé
There is a vast area of deserts and Gobi in the areas to the north of 35°N in China, which makes it one of the most important source regions of sandstorm in China, Asia or even the world, so it has a certain significance to make an analysis of it. An index was built and the characteristics of sand emission was analyzed on the basis of the days of dust storms and blowing sand of 277 weather stations in Northern China. Then the roles of relevant factors——vegetation coverage, wetness, strong wind days and thermal unstable days on sand emission were discussed and the environmental impacts was analyzed. The main conclusions are as follows :(1)By analyzing the temporal and spatial distribution of the sand emission index in Northern China, we found :①South Xinjiang District and Hexi District were the areas where it was most easy to blow sand away. The center was concentrated in Minfeng, Hetian in South Xinjiang District and Guaizihu, Minqin in Hexi District. It was not easy to blow sand up in Dongbei District. ② The sand emission index was higher in spring and summer while lower in autumn and winter. Spring was the most easy to blow sand and most of the regions reached the peak of the year in April. The smallest sand emission index occurred in winter in the districts of North Xinjiang District, South Xinjiang and Dongbei, and that of the other sub regions was in autumn. ③ The sand emission index has decreased since 1961 and the change key was in the 80s of twentieth century. After that, the sand emission index is gradually becoming smaller and smaller, especially in the 90s, when the decreasing trend was more obvious. And it’s harder to blow sand after 2000.(2) By analyzing the spatial correlation as well as temporal correlation of the sand emission index and its climatic factors, we found :① The vegetation coverage, wetness and unstable days showed significantly negative, negative and positive spatial correlation with the sand emission index, respectively. This illustrated that the land surface conditions of sand sources and unstable stratification factors played an important role on the regional distribution of sand. ② The roles of the climatic factors of which could impact the changes of sand emission index were different

Mots clés : sand emission index ;the north of China ;temporal and spatial distribution ;climatic causes ;sand emission rate ;air quality ;

Présentation (CNKI)

Page publiée le 15 avril 2022