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

Accueil du site → Master → Chine → 2013 → Analysis on the Grassland Degradation Situation and Its Recovery Mode of the Typical Area in Xinjiang

Université de Shihezi (2013)

Analysis on the Grassland Degradation Situation and Its Recovery Mode of the Typical Area in Xinjiang

毛继荣;

Titre : Analysis on the Grassland Degradation Situation and Its Recovery Mode of the Typical Area in Xinjiang

Auteur : 毛继荣;

Grade : Master’s Theses 2013

Université : Université de Shihezi

Résumé
Grassland degradation is the most important ecological and economic problems in the area of arid and semi-arid regions in China. Grassland degradation has become a major environmental problems. Grassland degradation affects sustainable development of animal husbandry in arid and semi-arid regions. The concept of grassland degradation varies with the research perspective. Therefore, the concept of different grassland degradation. It is also different emphasis. Currently, most of the degradation of natural grassland in Xinjiang. Grassland ecological environment is destroyed. The amount of animal husbandry sustainable development has been severely affected.The NDVI product images of NOAA/AVHRR from1981to2001and the NDVI product of SPOT VGA-NDVI from1998to2010were used to calculate vegetation coverage in Altay steppe, and then correlation coefficients between vegetation coverage and climate factors were employed to analyze the vegetation coverage changing trend and the reasons of the change. For1981-2009and annual grassland vegetation cover change analysis. Analysis of the causes of grassland change. Analysis of climate change on grassland degradation. Thus, to explore reasonable protection, development and utilization grasslands provide scientific and theoretical basis for countenneasures. The results shows that :(1) Changes in status for Altay prairie, grassland degradation clearly refers to the grassland ecosystem as a retrograde succession process, in this process, the system composition, structure and function changed significantly, the original energy flow downsizing, material circulation disorder, entropy increases, breaking the original steady state and orderliness order to lower energy conversion system, which is necessary to maintain ecological processes and even loss of ecological function decline, or at low level order form partial way top, creating a new metastable.(2) Altay region NDVI values change to reflect changes in vegetation cover, especially for grassland areas. Through the Altay region1980-2009regional vegetation NDVI variation can be seen, the average area of vegetation NDVI values showed an overall downward trend, especially in recent years has been to maintain vegetation cover lower level, where the annual maximum NDVI value dropped more obvious ; Altay region through vegetation growing season NDVI value analysis showed that industry growing season NDVI values showed significant downward trend.(3) Grassland biomass and grass height is an important indicator of good or bad quality pasture.2011on the Altay region’s comprehensive grassland resources survey shows that compared with1982, various types of grassland biomass decreased significantly, while the height of the grass there are different degrees of reduction, especially in steppe desert and desert steppe class category drop height clearly, this shows that grassland desertification Altay area is serious.(4) Altay region interannual variation of vegetation NDVI with precipitation changes, a phenomenon in the growing season and the annual average NDVI and annual variation in performance is particularly evident, suggesting that precipitation is the area of vegetation coverage change the dominant factor ; and for annual maximum NDVI values less obvious change was mainly due to annual maximum NDVI values generally between7-8months from the largest vegetation cover a ten-day data, with an average annual rainfall relationship is relatively small.(5) Since the Altay region in recent years increased precipitation and grassland degradation has shown clear trend, indicating that affect Altay grassland degradation is mainly due to human activities.(6) Altay prairie grazing activities in the long term, the typical fragile ecosystems in arid areas, the system is mainly affected by human factors. If you continue to blindly pursue the economic interests of grassland, increase grassland grazing, it will seriously damage grassland ecosystems, resulting in grassland degradation is increasing. Currently the focus should be strengthened degraded grassland protection, through fencing, rotational grazing, natural grassland reseeding, irrigation, establishment of artificial forage base and other measures to improve the ecological environment of the region, making the region’s ecological and economic benefits can simultaneously rational and rapid development

Mots clés : Altay; Degradation of steppe; Normalized Differential Vegetation Index; Precipitation; Temperature;

Présentation (CNKI)

Page publiée le 14 juin 2018