Spatiotemporal Changes Of Grassland Fire In Inner Mongolia In Recent 30 Years

Steppe ecosystem was an important role for the people who live in grazing district and sustainable economic development. Researching the natural calamities at pasture also had the attention from government. Being a disaster as prairie fire almost seems one of significant threaten for steppe ecosystem. According to the data based on the periods from 1981-2013,which were the prairie fire at inner Mongolia, researcher adopt by statistical analysis and GIS spatial statistics to research the feature of time and space in prairie fire and then analyzed the relationship among the Prairie fire pattern, precipitation and vegetation coverage The feature as rule of time was used by the traditional methods but spatial distribution pattern was obtained Arcgis10.2 kernel density function and hot spot analysis tool.The study in Pastoral areas of Inner Mongolia grassland fire pattern and precipitation and vegetation coverage put in ENVI and SPSS. Getting the results as:1. Time characteristicsBased on 1981-2000 the pastoral areas of Inner Mongolia grassland fire statistics and the MODIS data in 2000- 2013, using time series analysis methods analyze the time characteristics of the pastoral areas of Inner Mongolia grassland fire including annual variation, seasonal variation and the ten-day change rule. For nearly 30 years of grassland fire, there is a decrease in the pastoral areas of Inner Mongolia grassland fire trend in data.1987 is the biggest year in that Inner Mongolia grassland pastoral area loss caused by the fire nearly 30 years. From seasonal change, grassland fire season change, obviously. The fire in pastoral areas of Inner Mongolia grassland occurred in spring and autumn but winter and summer almost no prairie fire. Because summer is the grassland vegetation growth period, fuel moisture content is high, plants does not have the prairie fire behavior occurrence conditions. The low winter temperatures and grassland pastoral area is covered with ice and snow it is impossible to happen the prairie fire behavior. Change rules of grassland fire for month are analyzed prairie fire is mainly in 4, 5, 6 9and 10.2.SpatialfeatureBased on historical statistic data and 2000-2013 MCD45 product from the point of information using the average nearest neighbor Arcgis10.2 software tool, the density of nuclear analysis tools and hot spot analysis methods to analyze the nearly 30 years of pastoral areas of Inner Mongolia grassland fire of space distribution, the density of space and spatial frequency. The results show that the pastoral areas of Inner Mongolia in recent 10 years of distribution pattern of grassland fire behavior is clustering distribution, illustrate the prairie fire, behavior is not random, is produced by certain influence. A decade of grassland fire frequency is in the northeast of Inner Mongolia, such as northwest of hulun bei er including; Chen barr tiger flag and ewenki first-hand, xilingol league area in the northeast; East WuZhu MuQinQi and west ujimqin.3. Pastoral areas of Inner Mongolia grassland or pattern’s relationship with precipitation, vegetation coveragePastoral areas of Inner Mongolia grassland or pattern’s have relationship with precipitation, vegetation coverage. High annual rainfall, vegetation grew well, more than a year litter grasslands also, litter more fuel quantity is to increase the occurrence of grassland fire behavior, fire area is large.From the contrast of vegetation coverage and pastoral areas of Inner Mongolia grassland fire behavior distribution, high vegetation coverage areas of grassland fire behavior occurred more frequently, and the fire area is relatively large.The results showed that grassland vegetation coverage from the pastoral areas of Inner Mongolia northeast to the southwest has a tendency to gradually reduce, the occurrence of grassland fire behavior and fire area.