The Response Of The Oasis Climate In Yanqi Basin To The Changing Land Utilization

Oases and desert are the unique landscape types in arid northwest China, residesin the desert oasis among the fragile natural environment, combined with irrationalexploitation of people, so that the original oasis ecosystem and climate changed. Oasisin Arid Region of Northwest China the development of magnitude enhancement inrecent years, only4%of the Oasis station area gathered more than95%of thepopulation and90percent of the social wealth. Life on the Oasis of the protection andthe people are closely related, and therefore the importance of the oasis climate cannot be ignored, it is one of the important factors for sustainable development impact.This paper selects a representative oasis Yanqi Basin as the research object, using thelinear trend analysis, a total anomaly analysis, Mann-Kendall test methods such asanalysis of the past50years in the Yanqi Basin oasis climate (temperature,precipitation, evaporation) changes in the characteristics of the use of analysis of theYanqi Basin oasis of nearly30years of land use change, climate change and changesin the Yanqi Basin oasis land use dynamic analysis of the relationship between the useof the transfer matrix. The results showed that:1) Yanqi Basin oasis showed an increasing trend in temperature in the past50years, but the plain areas in the basin and the basin margin of Yamaguchi areas, there’sa big change in the temperature difference. The temperature of plains rise slowlybefore1980in the following50years the average temperature,20years after1990thetemperatures rising violent. In1990s Yanqi rise faster than the annual averagetemperature and static, and Master violent and static since2000, and a Master riseintense than the Yanqi; entire Yanqi Basin plains average annual temperature inmid-1990s the average temperature increase of30over the previous0.37℃, agrowth rate of43.68‰, compared with10years ago in the21st century1990sgrowth0.58℃, a growth rate of46.61‰, showing a relatively stable growth trend. Plains surrounding the Yamaguchi region showing a rising temperatures-decliningtrend in the1990s compared with the previous30-year average annual temperaturerose by0.972℃,2000after the mid-10’s average temperature over the previous90dropped0.523℃, but the overall temperature changes tends to rise. So nearly50years Yanqi Basin oasis temperatures rise, but nearly30years of rapid change,temperature change Plains region has continued to rise over the edge of the basindramatic changes in mean annual temperature. Seasonal temperature changes in basinplains from strong to weak once for winter, spring, fall, summer, but the performanceof the Yamaguchi District the most obvious changes in summer temperatures. It canbe seen that there is a significant difference in the Yanqi Basin, plain oasis oasis oftemperature changes and temperature changes Yamaguchi. In recent30years, with thesurrounding plains of the Yamaguchi District Yanqi Basin Basin, the average annualtemperature rising trend emerged, plains rising temperatures compared with theYamaguchi District obvious changes in temperature’s rising plains region, the regionshowed a rise trend in Yamaguchi-downward.2）The evaporation changes showed the opposite trend between basin plains andmountain pass from the nearly50years of the Yanqi Basinthe.The evaporation of theplains showed decline-rise, in the1990s the evaporation reduced violently inHeshuo and Hejing area, but flat in Yanqi,in10years before the21st centuryevaporation showed dramatic reduction in Yanqi, and small increase in Heshuo andHejing area, but the total showed a continued downward trend.From a seasonalperspective, evaporation in summer declined the most obviously, followed in springand followed in the fall, the evaporation in winter did not change significantly, andshowed a weak downward trend. In total, the evaporation in summer and autumn hadan important influence on the evaporation of Yanqi Basin. The evaporation of edgeregion in the Yanqi Basin showed an upward trend. Evaporation changes in the last30years around the region showed an increasing trend, and decreasing trend in plains.3)The annual precipitation in all stations of Yanqi basin plain area are showed atrend of obvious volatility rises in recent50years,until the1990s when the trend ofrise is gentle, the average stay in years and change slightly; However, the increase ofprecipitation in the90s is obvious, it’s almost50years altogether. In the21st century,the precipitation suddenly decreased, and then remain relatively stable volatilitychanges. The change trend of precipitation in summer half year and winter half yearmaintain a high level of consistency, and the change of summer precipitation is stable,and the change is bigger than winter, there are many years appear unstable andgradual change trend in winter, the rainfall in summer half year is the key to affect theprecipitation throughout the year. The Precipitation change tendency in yanqi basinaround the mountain is coincide to the plain area, but the change of precipitationintensity in the surrounding area is less insensitive than plain region. The precipitationchange tendency of the plains and the surrounding mountain pass area shows a highdegree of consistency in nearly30years; both are rising-falling tendency, but thebasin plain area is dramatic than the mountain pass area.4)The land use of Yanqi basin in the nearly30years has changed drastically,cultivated land area showed a trend of absolute growth, growth in68409.07hm2inthe90s, growing64052.64hm2in twenty years.Vegetation, saline-alkali land, unusedshowed a trend of absolute reduction and vegetation has reduced80234.79hm2,saline-alkali3052.17hm2, saline-alkali land3052.17hm2, unused land55924.51hm2.The change of water and wetland is alternant, the water in the90s has a growth of36774.09hm2, reduced29999.79hm2after2000, the total increase is6775.11hm2in30years, wetland reduced16054.29hm2in the90s, and increased6028.91hm2after2000, and thus it almost has no change.5)The climate change has a certain relationship with the of change land use,which mainly reflects on the changes of the temperature and evaporation, the annual average temperature increase obviously faster than the surrounding areas in Yanqibasin, and years of climate change in each three meteorological sites showed aconsistency with the development change trend of land use. the change tendency ofthe evaporation in basin plain and around the basin plain area has no consistency,basin plain area remain a trend of rising down warding, and the surrounding areashowed a trend of rising due to the large reduction of wet water and vegetation in theplain area.