NDVI Changes Responses To Climate Factors Of Different Sandy Landscape Area In Horqin Sandyland

It is a keystone to recognize relationship between plant and environmental factorsin different ecological scales under global climate change situation. For bestunderstanding the meterological factor change impact on vegetation productivitypattern in different sandy landscape areas, under the background of global climatechange，we employed "3S" technology to monitor and analyze the dynamic change ofvegetation In14years.According to the needs of research,we select3kinds of sandy landscape areas thatinclude sandy landscape of fenced sandy protective area, artificial afforestation andsand-fixation area, and mobile sand dune area,where we extract NDVI, landscapeindex and meteorological data.After analysis the interannual variation,we analyzechange trends of the NDVI,landscape indexand the meterological factor and relationbetween them that MODIS NDVI is used as an indictor of vegetation productivity andthe meterological factor include precipitation(year, critical period, maximum daily incritical period, important period) and air temperature(yearly mean, critical period mean,maximum daily mean in critical period, minimum daily mean in critical period),respectively. Select show no obvious correlation factor. Through the path analysis anddecision analysis, and finally get the geographic factor influencing characteristics,main controlling factors and find out the influence of NDVI and landscape change,comparison of different sandy landscape type changes in vegetation productivity andits response to climate change. The results showed that:(1) the NDVI change trends increased and the precipitation effect was moresignificantly than the temperature at overall level in different sandy landscape types.More research details also illustrated that precipitation was apparent positivecorrelation effect and the temperature was versa. Critical period precipitation was thedirect factor to influence the sandy landscape of fenced protective area, the decisioncoefficient was maximum and positive, and it reached0.455. Nevertheless, theagriculture reclaiming and woodland renewing reduced the effect of hydrothermalconditions to NDVI in the artificial afforestation and sand-fixation area, but it was stillremarkable to the important period precipitation had a greatest impact among thefactors by comparative identification. Beside the effect of extreme temperature in the critical period, rest fators was not obvious in the sandy landscape of mobile sand dunearea.(2) From the point of view of landscape index, landscape area of sand enclosureand artificial reforestation landscape district two vegetation protection is good, but alandscape advantage the enclosed area of artificial afforestation area of rise and decline;while the mobile dune landscape area showed a plaque gradually fragmentation andcomplex. In NP, the sand enclosing types of landscape area, the critical period ofminimum temperature and precipitation contributed important surface fragmentation,and the precipitation eased the artificial afforestation area of landscape types of surfacefragmentation, mobile dune landscape types on the contrary, the annual precipitation ismore, but the broken surface; in the LPI. The sand enclosing types of landscape area,the higher the temperature the landscape dominance more apparent, and the artificialafforestation landscape landscape pattern affected by human activities, landscape typesof sand dune area, limit the role of the key period of precipitation and temperature arethe highlights the dominance of inhibition.