山东农业科学
山東農業科學
산동농업과학
SHANGDONG AGRICULTURAL SCIENCES
2014年
9期
98-105
,共8页
归一化植被指数(NDVI)%植被覆盖度%NDVI差值指数%动态变化%宝鸡市
歸一化植被指數(NDVI)%植被覆蓋度%NDVI差值指數%動態變化%寶鷄市
귀일화식피지수(NDVI)%식피복개도%NDVI차치지수%동태변화%보계시
NDVI%Vegetation coverage%NDVI difference value%Dynamic change%Baoji City
植被覆盖度是反映地区生态环境的重要指标,本文利用1988、2000、2007年三期TM遥感数据,计算出宝鸡市的归一化植被指数( NDVI),并通过像元二分模型计算出不同时段的植被覆盖度,最后将归一化植被指数的差值进行分级,以此来分析宝鸡市1988~2007近20年的植被覆盖变化动态。结果表明:1988~2000年间,极低覆盖度、高覆盖度、极高覆盖度比例都呈现出减少趋势,减少比例分别为宝鸡市土地面积的0.02%、1.66%和1.98%,其他各级别植被覆盖度也都有不同程度下降;2000~2007年间,极高植被覆盖度增大的比例达到8.04%。 NDVI差值指数分级结果显示,1988~2000年植被退化明显,2000~2007年有大幅度改善;从长时间序列看,生态退化比较明显的区域是金台区、扶风县、岐山县、凤翔县。人为因素是影响植被覆盖变化的主要驱动因素,主要包括山区或平原区的生态绿化工程、城市景观绿化工程、农业产业结构调整、畜牧业发展、人口因素等。
植被覆蓋度是反映地區生態環境的重要指標,本文利用1988、2000、2007年三期TM遙感數據,計算齣寶鷄市的歸一化植被指數( NDVI),併通過像元二分模型計算齣不同時段的植被覆蓋度,最後將歸一化植被指數的差值進行分級,以此來分析寶鷄市1988~2007近20年的植被覆蓋變化動態。結果錶明:1988~2000年間,極低覆蓋度、高覆蓋度、極高覆蓋度比例都呈現齣減少趨勢,減少比例分彆為寶鷄市土地麵積的0.02%、1.66%和1.98%,其他各級彆植被覆蓋度也都有不同程度下降;2000~2007年間,極高植被覆蓋度增大的比例達到8.04%。 NDVI差值指數分級結果顯示,1988~2000年植被退化明顯,2000~2007年有大幅度改善;從長時間序列看,生態退化比較明顯的區域是金檯區、扶風縣、岐山縣、鳳翔縣。人為因素是影響植被覆蓋變化的主要驅動因素,主要包括山區或平原區的生態綠化工程、城市景觀綠化工程、農業產業結構調整、畜牧業髮展、人口因素等。
식피복개도시반영지구생태배경적중요지표,본문이용1988、2000、2007년삼기TM요감수거,계산출보계시적귀일화식피지수( NDVI),병통과상원이분모형계산출불동시단적식피복개도,최후장귀일화식피지수적차치진행분급,이차래분석보계시1988~2007근20년적식피복개변화동태。결과표명:1988~2000년간,겁저복개도、고복개도、겁고복개도비례도정현출감소추세,감소비례분별위보계시토지면적적0.02%、1.66%화1.98%,기타각급별식피복개도야도유불동정도하강;2000~2007년간,겁고식피복개도증대적비례체도8.04%。 NDVI차치지수분급결과현시,1988~2000년식피퇴화명현,2000~2007년유대폭도개선;종장시간서렬간,생태퇴화비교명현적구역시금태구、부풍현、기산현、봉상현。인위인소시영향식피복개변화적주요구동인소,주요포괄산구혹평원구적생태녹화공정、성시경관녹화공정、농업산업결구조정、축목업발전、인구인소등。
The vegetation coverage is an important indicator of the ecological environment in one region . In this paper , using TM remote sensing data in 1988 , 2000 and 2007 , the normalized difference vegetation in-dex ( NDVI) of Baoji was calculated .And the vegetation coverage of Baoji in different times was worked out through the pixel binary model .Finally, the difference of normalized difference vegetation index was classified to analyze the dynamic change of vegetation coverage in Baoji in the past 20 years from 1988 to 2007 .The re-sults showed that the extremely low coverage , high coverage and extremely high coverage all showed a decrease trend from 1988 to 2000, and the reduce proportion was 0.02%, 1.66%and 1.98%of Baoji land area re-spectively .The other levels of vegetation coverage also had different degrees of decline .The proportion of ex-tremely high vegetation coverage increased 8.04%from 2000 to 2007.NDVI difference value grading results showed that the vegetation degradation from 1988 to 2000 was serious , while the situation was improved during 2000 ~2007 .From long time series , the vegetation degradation mainly appeared in Jintai District , Fufeng County , Qishan County and Fengxiang County .Human factors were the main driving force that affecting the change of vegetation coverage , mainly including the ecological greening projects in mountains or plains , urban landscape greening projects , agricultural industrial structure adjustment , animal husbandry development , de-mographic factors, etc.