本文關(guān)鍵詞：錫林郭勒草原干旱災(zāi)害監(jiān)測(cè)與風(fēng)險(xiǎn)評(píng)估研究　出處：《中國農(nóng)業(yè)科學(xué)院》2016年博士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 氣候變化 蒸散發(fā) 干旱監(jiān)測(cè) 群落變化 風(fēng)險(xiǎn)評(píng)估

【摘要】：為進(jìn)一步提高錫林郭勒草原的干旱災(zāi)害監(jiān)測(cè)和防災(zāi)減災(zāi)能力,論文利用3S技術(shù)結(jié)合野外實(shí)地調(diào)查、數(shù)學(xué)建模、社會(huì)經(jīng)濟(jì)數(shù)據(jù)統(tǒng)計(jì)分析和自然災(zāi)害風(fēng)險(xiǎn)評(píng)估等方法,對(duì)錫林郭勒草原進(jìn)行干旱災(zāi)害監(jiān)測(cè)和風(fēng)險(xiǎn)評(píng)估等內(nèi)容的研究。研究結(jié)果表明:(1)近54年(1961~2014年)錫林郭勒草原年降水量呈下降趨勢(shì),氣候變化率為-1.46mm/10a;夏季和7~8月降水量均呈下降趨勢(shì);夏季降水量占全年的66.4%,7、8月降水量占全年的50.0%,年度和夏季降水量的下降主要是由7~8月降水量的下降引起的;空間上各年代200mm等降水量線呈東西波動(dòng)變化狀態(tài)。年、季、月尺度的氣溫均呈上升趨勢(shì),氣候變化率為0.41°C/10a,年平均氣溫在2℃以上區(qū)域所占面積逐步增加,2℃等溫線向東北方向小幅度推進(jìn)。(2)近15年(2000~2014年)蒸散發(fā)的年動(dòng)態(tài)表明,草甸草原的蒸散發(fā)在250mm上下波動(dòng),典型草原、沙地植被和總體在200mm上下波動(dòng),荒漠草原在150mm上下波動(dòng);季節(jié)動(dòng)態(tài)表明,草甸草原、典型草原、沙地植被和總體的蒸散發(fā)均為夏秋季冬春季,荒漠草原為秋冬季春夏季;月動(dòng)態(tài)表明,草甸草原、典型草原、沙地植被和總體的蒸散發(fā)均為7月和8月最高,而荒漠草原為11月和2月最高,各類草原的最低蒸散發(fā)均出現(xiàn)在5月。(3)基于實(shí)際蒸散發(fā)(ET)和潛在蒸散發(fā)(PET)的蒸散發(fā)虧缺指數(shù)(ETDI)與實(shí)測(cè)土壤含水量的相關(guān)性最高,建立的土壤含水量反演模型SVM=-48.851×ETDI+54.669(R2=0.62,RMSE=2.75%)的驗(yàn)證精度為RMSE=3.27%,該模型達(dá)到了區(qū)域土壤含水量快速反演的應(yīng)用水平。(4)近15年(2000~2014年)錫林郭勒草原的干旱年動(dòng)態(tài)表明,草甸草原基本無旱,典型草原、沙地植被和總體基本為輕旱,荒漠草原基本為重旱;近15年總體的無旱和重旱面積呈增加趨勢(shì)。月尺度上,各類草原返青期4~5月尤其5月的干旱程度較重,基本為中旱或重旱;草甸草原、典型草原和沙地植被6月的干旱程度均緩減,到盛草期7~8月基本為無旱或輕旱,到枯草期9~10月干旱進(jìn)一步緩減;而荒漠草原各月干旱均較重,基本為中旱或重旱。近15年錫林郭勒草原4~5月的重旱面積呈上升趨勢(shì),需要注意和加強(qiáng)預(yù)防返青期干旱。(5)主要群落變化分析表明,草甸草原和典型草原的禾本科植物優(yōu)勢(shì)度均明顯上升,菊科植物的優(yōu)勢(shì)度均明顯下降,豆科植物的相對(duì)重量均呈下降趨勢(shì),群落內(nèi)以禾本科植物為主的物種聚集程度增加,植物的個(gè)體數(shù)量向不均勻方向發(fā)展;荒漠草原的禾本科和菊科植物的優(yōu)勢(shì)度均下降,而其它科植物的優(yōu)勢(shì)度上升;典型草原和荒漠草原的物種豐富度下降,植物科、屬、種的數(shù)目均為下降趨勢(shì);各類草原的植物種類變化均較大、相似性較低。(6)錫林郭勒各旗縣市之間的干旱災(zāi)害風(fēng)險(xiǎn)差異較大,其中二連浩特市是干旱災(zāi)害風(fēng)險(xiǎn)極高區(qū)域;蘇尼特右旗、蘇尼特左旗和鑲黃旗是干旱災(zāi)害風(fēng)險(xiǎn)高的區(qū)域,風(fēng)險(xiǎn)僅次于二連浩特市;阿巴嘎旗、錫林浩特市和正鑲白旗是發(fā)生干旱災(zāi)害風(fēng)險(xiǎn)中等的區(qū)域;東西烏珠穆沁旗和正藍(lán)旗發(fā)生干旱災(zāi)害風(fēng)險(xiǎn)較低;多倫縣和太仆寺旗是發(fā)生干旱災(zāi)害風(fēng)險(xiǎn)極低的區(qū)域。近11年(2003~2013年)東西烏珠穆沁旗、阿巴嘎旗和錫林浩特市的干旱災(zāi)害風(fēng)險(xiǎn)均呈下降趨勢(shì),其它旗縣市的干旱災(zāi)害風(fēng)險(xiǎn)均呈上升趨勢(shì)。
[Abstract]:In order to further improve the drought disaster monitoring and disaster prevention and mitigation capacity of Xilinguole grassland, the use of 3S technology combined with field investigation, mathematical modeling, social economic data and statistical analysis of natural disaster risk assessment methods of drought disaster monitoring and risk assessment of Xilingol Grassland. The results show: (1) 54 years (1961~2014 years) the annual precipitation of Xilinguole grassland decreased, climate change rate of -1.46mm/10a and 7~8; summer precipitation decreased; summer precipitation accounted for 66.4%, 7,8 accounted for 50% of the annual precipitation decreased, annual and summer precipitation is mainly caused by the decline of 7~8 monthly precipitation the space in the 200mm; isohyet is fluctuation. Year, season, month scale temperature showed an upward trend, climate change rate is 0.41 ~ C /10a, the annual average temperature A gradual increase in the area occupied area of more than 2 DEG C, 2 C isotherm to the Northeast small forward. (2) in recent 15 years (2000~2014 years) the annual dynamic evapotranspiration showed that meadow evapotranspiration fluctuation in 250mm under typical steppe, vegetation and the overall in the 200mm wave, desert the fluctuation in 150mm grassland; seasonal dynamics showed that the meadow steppe, typical steppe, vegetation and the total evapotranspiration was in summer and autumn winter spring sandy desert grassland for spring summer autumn and winter months; dynamic show, meadow steppe, typical steppe, vegetation evapotranspiration and total body fat were highest in July and August, and the desert the grassland in November and highest in February and lowest of all kinds of sporadic steamed grassland appeared in May. (3) based on actual evapotranspiration (ET) and potential evapotranspiration (PET) evapotranspiration deficit index (ETDI) and the measured soil moisture is the highest, the establishment of soil moisture inversion Model SVM=-48.851 * ETDI+54.669 (R2=0.62, RMSE=2.75%) to verify the accuracy of RMSE=3.27%, the model achieves the application level of regional soil water content inversion. (4) in recent 15 years (2000~2014 years) in Xilingol Grassland drought year development indicates that the basic meadow grassland drought, typical steppe, sandy vegetation and general mild drought the basic, severe drought in desert steppe; nearly 15 years overall drought and severe drought area showed an increasing trend. The month scale, various types of grassland green period 4~5 months especially drought in May is heavy, basic for drought or heavy drought; meadow steppe, typical steppe and sandy vegetation in June were drought mitigation to 7~8, Sheng grass is mostly drought and light drought, 9~10 drought withered period further reduced; and each month in arid desert steppe were heavier, basic for drought or heavy drought. Nearly 15 years 4~5 months of heavy drought in Xilinguole grassland area increased to To pay attention to and strengthen the prevention of reviving period drought. (5) the main community change analysis shows that the typical steppe and meadow steppe grasses dominance increased obviously, Compositae dominance decreased and the relative weight of leguminous plants decreased in the community dominated by Poaceae species increase the aggregation degree the number of individual plants, unevendevelopment direction; desert steppe Gramineae and Compositae dominance decreased, while the other species dominance increased; species richness in typical steppe and desert steppe decreased, plant families, genera, species number was decreased; the change of all kinds of grassland plant species a large, low similarity. (6) the difference between the risk of drought disaster in Xilinguole flag counties of Erenhot city is larger, the high risk of drought disaster area; Sunite Right Banner, and Xianghuangqi is regional drought disaster risk high risk, second only to Erenhot city and Xilinhaote city; Abagaqi, Zhengxiangbaiqi region drought disaster risk is moderate; and something Ujimqin Zhenglanqi drought disaster risk is relatively low; Duolun County and Taipusiqi are regional drought disaster risk is extremely low. Nearly 11 years (2003~2013 years east Ujimqin), drought disaster risk in Xilinhaote city and the decreased drought disaster risk of other counties, is on the rise.

【學(xué)位授予單位】：中國農(nóng)業(yè)科學(xué)院
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2016
【分類號(hào)】：S812.6
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本文編號(hào)：1427836