Study On Dynamic Change Of Vegetation Coverage And Its Relationship With Meteorological Factors In Songhuaba Water Source Area

This article introduced the Landsat TM/ETM+ data with MODIS data, the existing water source reserve of weather stations of air temperature, rainfall data, using software ENVI4.8 and ArcGIS10.0 software and remote sensing, the use of the Pixel Unmixing model, linear regression and correlation analysis method, spatial and temporal variations in Songhua water source reserve basin of vegetation coverage and analyzes the change trend of temperature, precipitation, explore the main forest vegetation coverage and the correlation of meteorological factors, it is concluded that the main forest vegetation Songhua river basin and hydro meteorological factors change.The main research conclusions are as follows:1. The temperature distribution of:Loose China river basin in 1953-2010 main forest temperature change the rising trend of fluctuations, the range of the rise in temperature is 0.45℃/10 a, higher than the average temperature for nearly 50 years the national increase speed is 0.22℃/10 a, and 0.13℃/10 a global temperature increase of speed.2. The precipitation distribution:R/S analysis method to analyze the water conservation in 1953-2010 precipitation change, it is concluded that the pine China dam catchment areas precipitation showed a trend of the development, trend abate, and the continuity is not obvious. And loose dam catchment areas of precipitation change, between 1944 and 2010 in 56 years of average annual precipitation change present volatility change trend, rainfall in a downward trend, main forest decline rate is 0.6989 / a.3. The vegetation coverage change rule on the interannual and space:The loose Songhua river basin average main forest vegetation coverage, fluctuated in 25 years of change, but the overall average vegetation coverage rose 8.42% in 2012 compared to 1988, vegetation coverage value growth of 0.3368%/a. 1992~1994, up 11.2773% on the average vegetation coverage, up 1.0195% on the average vegetation coverage from 2000 to 2010, 2000 years later, vegetation coverage is slow. Integral space, 51.16% area of main forest regions of vegetation coverage is increased, the growth of the area are mainly concentrated in some mountains, the central region, in the northeast and southwest mountainous area, reduce the area concentrated in the north and northwest and southeast part of the region.Seasonal changes in vegetation characteristics in the study area, analysis of 13 years from 2000 to 2012, according to the results, every season average vegetation coverage appeared rising trend, especially in summer and autumn rising trend is more obvious; Four seasons of the distribution of vegetation coverage from big to small in turn is summer > autumn > spring > winter.4. The vegetation coverage and the temperature, precipitation correlation analysis:Loose Songhua river basin catchment areas have very good corresponding relationship between vegetation coverage and rainfall, from the overall present a positive correlation between annual precipitation and vegetation coverage, with the increase of precipitation and vegetation coverage increased as well. And water conservation vegetation coverage in 1988-2012 and the annual average temperature of the correlation coefficient is 0.824, showing a positive correlation. Correlation coefficient of 0.7430, with precipitation temperature correlation is higher than precipitation, show that the area is the main factor for the growth of vegetation temperature. Season main forest vegetation coverage and climate change show that vegetation coverage in summer precipitation change is consistent, both were positively correlated. Autumn and winter, precipitation and vegetation coverage changes in volatility. The spring of spring and autumn precipitation is relatively small, generally has a positive correlation.Loose China dam season main forest vegetation coverage change with temperature has certain correlation, the relationship between the spring and summer is the trend of changes in vegetation as the temperature rises to promote the increase of vegetation coverage, the spring and summer for the main growth period of vegetation growth.