Research On The Change Of Land Use/Cover And Ecological Vulnerability Of Ning’an City

Ning’an city located in the southeast of Heilongjiang Province. It’s located in the Zhangguangcailing of Changbai Mountains, among Laoye basin. Ning’an city belongs to the hilly area, the territory undulating, mountains staggered, widespread high hills, rivers, lying east, south and west sides, the middle and northern low. The forest landscape and farmland landscape of Ning’an city staggered distribution, and the frequent human activities become one of the biggest disturbance of the natural ecological environment. The change of landscape pattern damages the ecological function of the original. Ning’an city.is a typical ecological vulnerability zone of ecological environment, Because of the better foundation, its vulnerability is not obvious. Therefore, to understand the characteristics of regional land use/cover changing and ecological vulnerability, is an important foundation to promote the healthy development of ecological environment to ensure the stability of regional ecological environment.Based on relevant research at home and abroad, the related theories of land use/cover change and ecological vulnerability connotation are analyzed, and the theoretical basis for research. On this basis, this paper choose Ning An City of Heilongjiang Province as the study area, remote sensing image in1991,2000,2010as the main information source, and through visual interpretation, to extraction the land use/cover information of study area in1991,2000and2010. By GIS techniques and related models, this paper analyzes the study area for20years of land use/cover change feature; selected landscape indices to build ecological vulnerability model, and try to analyze the study area for20years ecological temporal and spatial variation of vulnerability On this basis, the article proposed ecological security countermeasures and suggestions in the study area of sustainable use of land resources.The results show that:Throughout the study period, grassland and woodland obvious show decreasing trend, respectively at a net decrease of33,500hm and30,300hm2;The arable land shows strong growth trend at a net increase of59,900hm2; Construction land increased, and a net increase of05,700hm2。 Waters and other sites have a slight decrease, respectively,400and1400hm2. Conversion of arable land and grassland, woodland and woodland and grassland is the main content of land use/cover type conversion. Study area in1991,2000and2010, the comprehensive index of land use degree were223.49,228.46and232.96. Generally speaking, the land use degree of study area in twentieth Century90years is relatively low, with the deepening development of land, by the late90’s and early twenty-first Century, the land use degree gradually increased. Through the landscape types of vulnerability model, the ecological vulnerability degree of arable land and construction land were the highest, and showed an upward trend year by year.1991～2010years, the arable land and construction land were increased by7.39%and0.7%, and two kinds of landscape disturbance from human activity, not suitable for farming land was cleared, and the increase of the construction land, intensified the ecological system instability. From1991to2010, the region’s arable land and construction land increased by7.39%and0.7%, respectively, and two types of landscape disturbance by human activities is the largest. Unsuitable for farming land was cultivated, and increased construction land exacerbated instability of the ecosystem. The study area’s ecological vulnerability index of1991,2000and2010statistics show that ecological vulnerability index of the61.7%in the sample area increased; Good ecological area significantly reduced and then increased; Mild vulnerable area increased slightly and then declined; General vulnerable area is decreased; Moderate vulnerable area increased and then slightly reduced; serious vulnerable area increased sharply in20years. Middle-high vulnerability area in increasing proportion, slightly vulnerability area in decreasing proportion, the ecological vulnerability growing.1991,2000and2010ecological vulnerability index of study area ordinary kriging interpolation results showed that:ecological vulnerability increased year by year; The vulnerability index was the highest in north-central, extension gradually reducing and middle-high vulnerability area gradually expanding in the study area. In20years, serious vulnerable area from scattered to concentrated, and gradually expand; general vulnerable area and mild vulnerable area around the serious vulnerable area, and to the extension of the rolling,20years, the proportion increased and then decreased.