沙漠与绿洲气象
沙漠與綠洲氣象
사막여록주기상
Desert and Oasis Meteorology
2015年
4期
1-7
,共7页
陈峰%袁玉江%张瑞波%喻树龙
陳峰%袁玉江%張瑞波%喻樹龍
진봉%원옥강%장서파%유수룡
巴丹吉林沙漠%树木年轮%NDVI重建%西风
巴丹吉林沙漠%樹木年輪%NDVI重建%西風
파단길림사막%수목년륜%NDVI중건%서풍
Badain Jaran Desert%tree-ring%NDVI reconstruction%westerlies
利用巴丹吉林沙漠南缘山地3个采样点的青海云杉树轮样本研制出区域树轮宽度年表。相关分析发现区域树轮宽度年表与5—7月NDVI变化有较好相关性,相关系数为0.670(P<0.001)。利用线性回归模型重建了巴丹吉林沙漠南缘山地1765—2010年5—7月NDVI变化,方差解释量为44.9%。NDVI重建序列揭示在1765—2010年期间巴丹吉林沙漠南缘山地有10个植被生长良好时段和10个植被生长较差时段。同时,NDVI重建序列的低值与河西走廊极端干旱历史事件有着良好的一致性。多窗谱周期分析发现,巴丹吉林沙漠南缘山地5—7月NDVI重建序列具有11.4,8.1,4.9,3.4,2.4 a的准周期变化。交叉小波分析发现太阳黑子活动是区域NDVI变化的重要驱动力之一。基于NDVI与区域干湿变化良好相关,分析了极端低值年份和极端高值年份的矢量风场距平变化发现区域NDVI变化与大范围气候场变化有显著关联,发现当西风增强时,研究区气候偏湿,有利于树木生长,NDVI值偏高,形成较宽的树轮。当研究区被来自北面沙漠地区气流控制时候,研究区气流偏干,不利于树木生长。
利用巴丹吉林沙漠南緣山地3箇採樣點的青海雲杉樹輪樣本研製齣區域樹輪寬度年錶。相關分析髮現區域樹輪寬度年錶與5—7月NDVI變化有較好相關性,相關繫數為0.670(P<0.001)。利用線性迴歸模型重建瞭巴丹吉林沙漠南緣山地1765—2010年5—7月NDVI變化,方差解釋量為44.9%。NDVI重建序列揭示在1765—2010年期間巴丹吉林沙漠南緣山地有10箇植被生長良好時段和10箇植被生長較差時段。同時,NDVI重建序列的低值與河西走廊極耑榦旱歷史事件有著良好的一緻性。多窗譜週期分析髮現,巴丹吉林沙漠南緣山地5—7月NDVI重建序列具有11.4,8.1,4.9,3.4,2.4 a的準週期變化。交扠小波分析髮現太暘黑子活動是區域NDVI變化的重要驅動力之一。基于NDVI與區域榦濕變化良好相關,分析瞭極耑低值年份和極耑高值年份的矢量風場距平變化髮現區域NDVI變化與大範圍氣候場變化有顯著關聯,髮現噹西風增彊時,研究區氣候偏濕,有利于樹木生長,NDVI值偏高,形成較寬的樹輪。噹研究區被來自北麵沙漠地區氣流控製時候,研究區氣流偏榦,不利于樹木生長。
이용파단길림사막남연산지3개채양점적청해운삼수륜양본연제출구역수륜관도년표。상관분석발현구역수륜관도년표여5—7월NDVI변화유교호상관성,상관계수위0.670(P<0.001)。이용선성회귀모형중건료파단길림사막남연산지1765—2010년5—7월NDVI변화,방차해석량위44.9%。NDVI중건서렬게시재1765—2010년기간파단길림사막남연산지유10개식피생장량호시단화10개식피생장교차시단。동시,NDVI중건서렬적저치여하서주랑겁단간한역사사건유착량호적일치성。다창보주기분석발현,파단길림사막남연산지5—7월NDVI중건서렬구유11.4,8.1,4.9,3.4,2.4 a적준주기변화。교차소파분석발현태양흑자활동시구역NDVI변화적중요구동력지일。기우NDVI여구역간습변화량호상관,분석료겁단저치년빈화겁단고치년빈적시량풍장거평변화발현구역NDVI변화여대범위기후장변화유현저관련,발현당서풍증강시,연구구기후편습,유리우수목생장,NDVI치편고,형성교관적수륜。당연구구피래자북면사막지구기류공제시후,연구구기류편간,불리우수목생장。
A regional tree-ring chronology of Picea crassifolia spanning 1765-2010 was developed from the southern edge of the Badain Jaran Desert, northwestern China. The climate/NDVI response analysis shows the regional tree-ring chronology have a good correlation (r=0.670)with May-July NDVI. Based on the regional tree-ring chronology, we developed a May-July NDVI reconstruction of the southern edge of the Badain Jaran Desert for the period AD 1765-2010. The NDVI/tree-growth model accounts for 44.9% of the observed NDVI variance during the period 1982-2006. Ten high NDVI periods (NDVI values higher than the average of reconstruction) and ten low NDVI periods (NDVI values lower than the average) was found during 1765-2010 respectively, and reflected the strong-weak changes of the Westerlies. There is a reasonable agreement with climatic extremes previously estimated from documentary records in northwest China. The results reveal common climatic extremes over much of Gansu. Many of these events have had profound impacts on the peoples of the Hexi Corridor over the past several centuries. The multitaper method (MTM) spectral analysis indicates the existence of 11.4 years,8.1 years,4.9 years,3.4 years and 2.4 years cycles, which may potentially be the fingerprints of some proposed climate change forcings. Preliminary analysis of links between large-scale climatic variation and the NDVI reconstructions shows that there is a relationship between extremes in NDVI reconstruction and anomalous atmospheric circulation in the region,and revealed that the westerlies have the great effects on the NDVI changes of the study area.