地球信息科学学报
地毬信息科學學報
지구신식과학학보
GEO-INFORMATION SCIENCE
2014年
3期
426-434
,共9页
草地覆盖度%土壤风蚀%RWEQ模型%防风固沙%锡林郭勒盟
草地覆蓋度%土壤風蝕%RWEQ模型%防風固沙%錫林郭勒盟
초지복개도%토양풍식%RWEQ모형%방풍고사%석림곽륵맹
vegetation coverage%wind erosion%RWEQ model%soil retention%Xilingol League
锡林郭勒盟为我国北方典型草原区,草地的退化与恢复影响生态系统的防风固沙服务功能。为了便于制定区域生态恢复的防治措施,实现草地生态系统的可持续发展与防治土壤风蚀危害,本文基于气象、遥感数据,运用RWEQ(Revised Wind Erosion Equation)模型,结合锡林郭勒盟的草地覆盖度变化对20世纪90年代以来的防风固沙服务功能的时空变化趋势进行了定量评估,并分析了草地覆盖度变化对防风固沙服务功能的影响。研究表明:锡林郭勒盟土壤风蚀以微度和轻度侵蚀为主,主要集中在植被盖度较高、降水相对较多,风场强度相对较低的东部、中部和南部地区;中度以上区域主要集中在西部的荒漠草原区与浑善达克沙地区,且侵蚀面积随侵蚀强度的增加而递减;防风固沙服务功能量的分布趋势与土壤风蚀模数的分布趋势基本一致;防风固沙服务功能保有率的分布特征与植被盖度的分布特征基本一致,表现为由西北到东南逐渐增加的趋势;在气候暖干化背景下,受京津风沙源治理工程实施的影响,以微度和轻度侵蚀为主的草地覆盖度减小区转为以微度和轻度为主的覆盖度增加区,轻度和中度以上侵蚀为主的草地覆盖度减小区转为基本持衡区;草地覆盖度的降低与增加对土壤风蚀的加剧和抑制作用明显,大部分地区的防风固沙服务功能保有率的下降(提升)与风蚀季节草地覆盖度的减小与提升呈显著正相关(r>0.6,p<0.05)。
錫林郭勒盟為我國北方典型草原區,草地的退化與恢複影響生態繫統的防風固沙服務功能。為瞭便于製定區域生態恢複的防治措施,實現草地生態繫統的可持續髮展與防治土壤風蝕危害,本文基于氣象、遙感數據,運用RWEQ(Revised Wind Erosion Equation)模型,結閤錫林郭勒盟的草地覆蓋度變化對20世紀90年代以來的防風固沙服務功能的時空變化趨勢進行瞭定量評估,併分析瞭草地覆蓋度變化對防風固沙服務功能的影響。研究錶明:錫林郭勒盟土壤風蝕以微度和輕度侵蝕為主,主要集中在植被蓋度較高、降水相對較多,風場彊度相對較低的東部、中部和南部地區;中度以上區域主要集中在西部的荒漠草原區與渾善達剋沙地區,且侵蝕麵積隨侵蝕彊度的增加而遞減;防風固沙服務功能量的分佈趨勢與土壤風蝕模數的分佈趨勢基本一緻;防風固沙服務功能保有率的分佈特徵與植被蓋度的分佈特徵基本一緻,錶現為由西北到東南逐漸增加的趨勢;在氣候暖榦化揹景下,受京津風沙源治理工程實施的影響,以微度和輕度侵蝕為主的草地覆蓋度減小區轉為以微度和輕度為主的覆蓋度增加區,輕度和中度以上侵蝕為主的草地覆蓋度減小區轉為基本持衡區;草地覆蓋度的降低與增加對土壤風蝕的加劇和抑製作用明顯,大部分地區的防風固沙服務功能保有率的下降(提升)與風蝕季節草地覆蓋度的減小與提升呈顯著正相關(r>0.6,p<0.05)。
석림곽륵맹위아국북방전형초원구,초지적퇴화여회복영향생태계통적방풍고사복무공능。위료편우제정구역생태회복적방치조시,실현초지생태계통적가지속발전여방치토양풍식위해,본문기우기상、요감수거,운용RWEQ(Revised Wind Erosion Equation)모형,결합석림곽륵맹적초지복개도변화대20세기90년대이래적방풍고사복무공능적시공변화추세진행료정량평고,병분석료초지복개도변화대방풍고사복무공능적영향。연구표명:석림곽륵맹토양풍식이미도화경도침식위주,주요집중재식피개도교고、강수상대교다,풍장강도상대교저적동부、중부화남부지구;중도이상구역주요집중재서부적황막초원구여혼선체극사지구,차침식면적수침식강도적증가이체감;방풍고사복무공능량적분포추세여토양풍식모수적분포추세기본일치;방풍고사복무공능보유솔적분포특정여식피개도적분포특정기본일치,표현위유서북도동남축점증가적추세;재기후난간화배경하,수경진풍사원치리공정실시적영향,이미도화경도침식위주적초지복개도감소구전위이미도화경도위주적복개도증가구,경도화중도이상침식위주적초지복개도감소구전위기본지형구;초지복개도적강저여증가대토양풍식적가극화억제작용명현,대부분지구적방풍고사복무공능보유솔적하강(제승)여풍식계절초지복개도적감소여제승정현저정상관(r>0.6,p<0.05)。
China is one of the countries suffering severely from soil wind erosion in the world, especially in the typical northern steppe. Xilingol League in Inner Mongolia is a part of the typical steppe zone. Ever since Bei-jing-Tianjin Dust Storms Sources Control Project was established in 2002, the grassland degradation situation has been controlled. The change of vegetation coverage can affect the ecological function of windbreak and sand-fixation. In order to prepare the prevention and control measures for regional ecological restoration, to un-derstand the practical significances of sustainable development of grassland ecosystem, and to control soil wind erosion, in this study, based on the meteorology and remote sensing data, combined with grassland degradation and recovery in Xilingol League, the Revised Wind Erosion Equation (RWEQ) was applied to quantitatively evaluate the spatio-temporal variations of soil conservation service function since the 1990s and to reveal the ef-fects of the change of vegetation coverage on soil wind erosion control service. The results are shown as follows. The intensity of soil wind erosion was low in the most regions of Xilingol League, Especially in the eastern, cen-tral and southern regions, with higher vegetation coverage, lower wind field intensity, and abundant rainfall. The wind erosion regions with medium and higher soil wind erosion intensity were mainly distributed in the western desert steppe and Otindag Sandy Land, and the area of these regions decreased progressively as the erosion inten-sity increased. The distribution pattern of soil retention was similar to soil wind erosion modulus. The distribu-tion characteristics of the soil retention rate were similar to the vegetation coverage, indicating a gradually in-creasing trend from northwest to southeast. Under the comprehensive influence of the warming-drying climate and the implementation of Beijing-Tianjin Dust storm Source Control Project, the vegetation coverage decreas-ing regions dominated by slight and micro erosion intensity turned into vegetation coverage increasing grassland dominated by slight and micro erosion intensity;the grassland having mild, medium or severe degree of vegeta-tion coverage reduction turned into the grassland with balanced vegetation coverage. The decrease or increase of vegetation coverage can significantly intensify or mitigate the soil wind erosion. Additionally, the soil retention rate showed a significant positive relationship with the grassland vegetation coverage in the spring seasons in most regions(r>0.6, p<0.05).