Study On The Vegetation Change And Its Influencing Factors Of Upland Meadow In Dahaituo Nature Reserve

Meadow is an independent natural complex, which is rich in plant, animal and microbial resources. The meadow vegetation of Dahaituo Nature Reserve in Hebei is typical, and the meadow type is diverse. We analyze the relationship between meteorological factors, social economic development and meadow vegetation change in Dahaituo Nature Reserve. It can provide guidance for environmental protection and "ecological Chicheng" to Chicheng County.In nearly 36 years, in this paper, the upland meadow vegetation as research object in Dahaituo Nature Reserve. We are based on remote sensing data in last 30 years and analyze the situation of patch area change, different slope change and different exposure change. We analyze the relationship between climate change and social economic situation and the meadow vegetation change which is based on the development of social economy, such as population change, urban population change, economic change, industry change, and climate change in Dahaituo Nature Reserve. The conclusions are drawn as follows:(1) At present, the meadow area of Dahaituo nature reserve is about 150 hm2, but in the medium and long term, meadow area decrease; meadow mainly grows in sunny slope. The area of sunny slope is 2.5 times larger than the area of shady slop; in general, the change of the proportion of the meadow slope is stable.(2) Nearly 36 years, the average annual precipitation changes of the meadow area in Dahaituo nature reserve showed cyclic fluctuation, and rise slightly. The annual average temperature increased significantly, and mainly caused by the increase of temperature in January (winter). Changes of meadow area were negatively correlated with annual temperature change, and positive correlation with annual precipitation change, but were not significant. Correlation between changes of meadow area and annual precipitation is greater than the annual temperature. The growth of the meadow and annual temperature was negative correlation and was significant, which mainly caused by the average temperature in January. The growth of the meadow and annual precipitation was positive correlation and was not significant.(3) Analysis of social and economic data shows that, in recent 30 years, the gross domestic product and population of Chicheng county has a significant upward trend. The agricultural population and the cultivated land area all have the obvious downward trend. The change of meadow area was negatively correlated with population and GDP, but it was not significant. Correlation between the change of meadow area and the change of GDP is stronger than the correlation between the change of meadow area and the population. By comparison, the change of meadow area was positively correlated with the agricultural population and cultivated land area, and both were significant. GDP may be the economic factor that to be more likely than the population of agriculture to cause the changes of the meadow.The growth of the meadow was negatively correlated with the population and GDP, and showed a significant correlation. In contrast, with the agricultural population and the area of cultivated land area is not significant. Population is the main factor that affects the growth of meadow.Based on the above analysis, the results showed as followed:the relationship between the change of meadow area and climate factors or social and economic factors were not significant. The Meadow growth was significantly correlated with the mean temperature of January in climatic factors and population in social and economic factors. It showed that the lower the temperature in the meadow, the better the growth of the meadow, the more population, the worse the growth of the meadow.