The Evaluation Of Index Systems Of Karst Vegetation Natural Restoration In Guizhou

The evaluation of Karst forest vegetation restoration has become one of the focused problems of restoration ecology,and many ecological scholars pay attention to it.In this paper,105 typical samples have been surveyed,using systematic clustering analysis,principal component analysis and analytical hierarchy process(AHP) to establish the evaluation of index systems and quantitive criteria of karst vegetation natural restoration in Guizhou.This study not only perfected basic study of degraded ecosystem vegetation restoration in kast mountain area of Guizhou, but also improved to recognize theory level of degraded ecosystem in karst.The main study results were as following:(1) The degradation of ecosystem of typical karst mountain is mainly caused by two reasons:the first is natural reasons,including weather,lithology,geological structure movement and characteristics of topography-landform,the second is anthropogenic reasons,namely human disturbance and destruction,such as cut,herd, reclamation,fire etc.(2) The evaluation of index systems of karst vegetation natural restoration in Guizhou were composed of 7 principles.(3) The 22 factors have beem screened out from the 27 factors that is closely relationship with karst vegetation restoration,to establish the evaluation of index systems and quantitive criteria of karst vegetation natural restoration in Guizhou.At the same time,the comprehensive evaluation model of vegetation restoration have been estalished.Karst vegetation of Guizhou were evaluated in the productivity, organizational structure and soil characteristics sides.(4) The degraded communities of karst were divided into six stages,namely herbaceous stage,scrub-herbaceous stage,shrub-scrub stage,shrub-arbor stage,arbor stage and climax arbor stage by a method of combination of systematic clustering analysis and principal component analysis.(5) By analytical hierarchy process(AHP),the evaluation of index systems of karst vegetation natural restoration in Guizhou were divided into five levels,namely one level was 0～0.15 for the poor,two levels were 0.15～0.30 for the general,three levels were 0.30～0.50 for the better,four levels were 0.50～0.75 for the very good, five levels were 0.75～1 for the best.(6) With the development of natural restoration of vegetation from low level stage to advanced stage,the comprehensive object restoration index of karst vegetation natural restoration in Guizhou were increased,the lowest was 0.0702,the highest was 0.9157.The restoration index of arbor stage and climax arbor stage were higher than others.The productivity,organizational structure and soil characteristics restorated very good,it showed the structure and function of community have restorated gradually.(7) The restoration index of productivity and organizational structure of different restoration stage in different climatic zone were incressed with the course of vegetation restoration in karst degraded community,but in the same restoration stage Libo county's index was significantly higher than Puding county's.The soil characteristics of Puding and Libo wer increasing trend in addition to the scrub-herbaceous stage of Puding and the shrub-scrub stage of Libo.In the same restoration stage,in addition to the arbor stage of Puding,the restoration stages of Libo were significantly higher than those of Puding.(8) Taking the same and different index weight to obtain object restoration index of different restoration stage in different climatic zone were not significantly different in karst degraded community.