林业科学
林業科學
임업과학
Scientia Silvae Sinicae
2015年
10期
35-42
,共8页
植被覆盖指数(FVC)%Sen+Mann-Kendall趋势分析%空间自相关分析%空间分布特征%新疆
植被覆蓋指數(FVC)%Sen+Mann-Kendall趨勢分析%空間自相關分析%空間分佈特徵%新疆
식피복개지수(FVC)%Sen+Mann-Kendall추세분석%공간자상관분석%공간분포특정%신강
fractional vegetation cover( FVC)%Sen + Mann-Kendall trend analysis%spatial auto-correlation analysis%spatial distribution characteristics%Xinjiang
【目的】对新疆植被覆盖变化的空间自相关性进行分析，研究植被覆盖的时间变化特征、空间分布特征及变化趋势等，为改善区域生态环境提供参考。【方法】利用新疆1998—2012年 NDVI数据，采用像元二分法获取植被覆盖指数( FVC)数据，在此基础上运用 Sen+Mann-Kendall 趋势分析和空间自相关分析方法，研究新疆植被覆盖的变化趋势特征和空间分布的聚集性特点。【结果】1)15年间新疆植被覆盖度略有下降趋势，山地和平原均呈下降趋势，山地较平原变化大。2) Sen +Mann-Kendall趋势分析可反映新疆 FVC 变化趋势的空间分布特点，全疆植被改善区域占25%，退化区域占28%，47%的区域变化不大，其中明显改善区域和严重退化区域所占比例均为10%左右。植被改善区域主要分布在天山北坡一带，退化区域主要分布在山地和平原的交错带，伊犁地区退化程度尤为严重。植被覆盖度极低地区基本不变，退化区域主要分布在植被低覆盖度区域周围。3)空间自相关分析进一步验证了 Sen+Mann-Kendall 趋势分析结果，新疆植被有明显的聚集现象。全局自相关性分析表明，当距离大于3 km后，空间自相关影响不大。局部相关性分析表明，新疆植被覆盖以“高－高聚集”和“低－低聚集”为主。【结论】植被盖度相对较高的地区植被覆盖越易改善，盖度较低或无覆盖的地区越难改善，而且退化越明显。根据植被盖度的聚集性可以看出，植被覆盖呈现明显的“高－高聚集”和“低－低聚集”格局，这与区域气候、水资源分布及人类活动的影响有着潜在的联系。今后可重点分析植被覆盖变化的影响因素，以了解干旱区植被覆盖变化的驱动机制。由于人类活动在短时期内对植被覆盖变化的影响比较显著，因此在空间上分析人类活动对植被覆盖变化的影响可为改善干旱区植被覆盖提供相应指导。【其他】本文从植被覆盖的空间聚集性解释了植被覆盖变化特点，一方面是对 Sen+Mann-Kendall 趋势分析的验证，另一方面为整体分析植被的变化特征提供了依据。
【目的】對新疆植被覆蓋變化的空間自相關性進行分析，研究植被覆蓋的時間變化特徵、空間分佈特徵及變化趨勢等，為改善區域生態環境提供參攷。【方法】利用新疆1998—2012年 NDVI數據，採用像元二分法穫取植被覆蓋指數( FVC)數據，在此基礎上運用 Sen+Mann-Kendall 趨勢分析和空間自相關分析方法，研究新疆植被覆蓋的變化趨勢特徵和空間分佈的聚集性特點。【結果】1)15年間新疆植被覆蓋度略有下降趨勢，山地和平原均呈下降趨勢，山地較平原變化大。2) Sen +Mann-Kendall趨勢分析可反映新疆 FVC 變化趨勢的空間分佈特點，全疆植被改善區域佔25%，退化區域佔28%，47%的區域變化不大，其中明顯改善區域和嚴重退化區域所佔比例均為10%左右。植被改善區域主要分佈在天山北坡一帶，退化區域主要分佈在山地和平原的交錯帶，伊犛地區退化程度尤為嚴重。植被覆蓋度極低地區基本不變，退化區域主要分佈在植被低覆蓋度區域週圍。3)空間自相關分析進一步驗證瞭 Sen+Mann-Kendall 趨勢分析結果，新疆植被有明顯的聚集現象。全跼自相關性分析錶明，噹距離大于3 km後，空間自相關影響不大。跼部相關性分析錶明，新疆植被覆蓋以“高－高聚集”和“低－低聚集”為主。【結論】植被蓋度相對較高的地區植被覆蓋越易改善，蓋度較低或無覆蓋的地區越難改善，而且退化越明顯。根據植被蓋度的聚集性可以看齣，植被覆蓋呈現明顯的“高－高聚集”和“低－低聚集”格跼，這與區域氣候、水資源分佈及人類活動的影響有著潛在的聯繫。今後可重點分析植被覆蓋變化的影響因素，以瞭解榦旱區植被覆蓋變化的驅動機製。由于人類活動在短時期內對植被覆蓋變化的影響比較顯著，因此在空間上分析人類活動對植被覆蓋變化的影響可為改善榦旱區植被覆蓋提供相應指導。【其他】本文從植被覆蓋的空間聚集性解釋瞭植被覆蓋變化特點，一方麵是對 Sen+Mann-Kendall 趨勢分析的驗證，另一方麵為整體分析植被的變化特徵提供瞭依據。
【목적】대신강식피복개변화적공간자상관성진행분석，연구식피복개적시간변화특정、공간분포특정급변화추세등，위개선구역생태배경제공삼고。【방법】이용신강1998—2012년 NDVI수거，채용상원이분법획취식피복개지수( FVC)수거，재차기출상운용 Sen+Mann-Kendall 추세분석화공간자상관분석방법，연구신강식피복개적변화추세특정화공간분포적취집성특점。【결과】1)15년간신강식피복개도략유하강추세，산지화평원균정하강추세，산지교평원변화대。2) Sen +Mann-Kendall추세분석가반영신강 FVC 변화추세적공간분포특점，전강식피개선구역점25%，퇴화구역점28%，47%적구역변화불대，기중명현개선구역화엄중퇴화구역소점비례균위10%좌우。식피개선구역주요분포재천산북파일대，퇴화구역주요분포재산지화평원적교착대，이리지구퇴화정도우위엄중。식피복개도겁저지구기본불변，퇴화구역주요분포재식피저복개도구역주위。3)공간자상관분석진일보험증료 Sen+Mann-Kendall 추세분석결과，신강식피유명현적취집현상。전국자상관성분석표명，당거리대우3 km후，공간자상관영향불대。국부상관성분석표명，신강식피복개이“고－고취집”화“저－저취집”위주。【결론】식피개도상대교고적지구식피복개월역개선，개도교저혹무복개적지구월난개선，이차퇴화월명현。근거식피개도적취집성가이간출，식피복개정현명현적“고－고취집”화“저－저취집”격국，저여구역기후、수자원분포급인류활동적영향유착잠재적련계。금후가중점분석식피복개변화적영향인소，이료해간한구식피복개변화적구동궤제。유우인류활동재단시기내대식피복개변화적영향비교현저，인차재공간상분석인류활동대식피복개변화적영향가위개선간한구식피복개제공상응지도。【기타】본문종식피복개적공간취집성해석료식피복개변화특점，일방면시대 Sen+Mann-Kendall 추세분석적험증，령일방면위정체분석식피적변화특정제공료의거。
Objective]Fractional vegetation cover( FVC) can reflect the status of land use/cover enougth,especially the arid areas where are sensitive to vegetation change degree significantly. Xinjiang belongs to arid areas,because of the influence of human activities and climate change vegetation cover in Xinjiang has changed in recent years. Therefore,it is necessary to monitor and investigate the change of Xinjiang vegetation cover dynamically,which would provide a reference for improving regional ecological environment. [Method]Based on the NDVI data from 1998 to 2012 of Xinjiang and the FVC data obtained by using dichotomy,this paper studied the characteristics of vegetation changing trend and its spatial clustering distribution through Sen + Mann Kendall trend analysis and spatial auto-correlation analysis. [Result]The results show that:1) The vegetation cover declines slightly among 15 years in Xinjiang. 2) Sen + Mann Kendall analysis reflects the spatial distribution characteristics of FVC changing trend in Xinjiang. Improvement areas of vegetation cover are mainly distributed in the north slope of Tianshan Mountain,and degradation areas are mainly distributed in the ecotone of mountains and plains,degradation degree is particularly severe in Ili region. Meanwhile,the areas with very low vegetation coverage remain unchanged basically,and degradation areas are mainly distributed around the low coverage region. 3) The spatial auto-correlation analysis further verifies the results of Sen + Mann Kendall analysis. Vegetation cover exhibits apparent agglomeration phenomenon in Xinjiang. Partial correlation analysis shows that vegetation coverage is given priority to“high-high concentration”and“low-low concentration”.[Conclusion]It can be seen that the relatively high vegetation coverage areas are easier to be improved,while low coverage areas or areas without coverage are more difficult to be improved, and present obvious degradation. According to the clustering characteristics of vegetation coverage,vegetation coverage presents obviously“H -H gathered”and“L-L gathered”pattern. This phenomenon has potential links with the regional climate,water resources distribution and the influence of human activities. In order to understand the driving mechanism of vegetation change in arid areas,we can analyze the affecting factors on the changes of vegetation cover in the future. Due to the influence of human activities on vegetation coverage change in a short period is more significant,the space analysis can provide corresponding guidance for improving vegetation in arid areas. [Other]This paper explains the characteristic of vegetation changes from the perspective of vegetation spatial clustering. On the one hand,it validate the results of Sen + Mann Kendall trend analysis,on the other hand,it would provide a basis for the overall analysis of characteristics of the vegetation changes.
