Health Evaluation Of Artificial Ecological Public Welfare Forest In Typical Small Watershed Of Alpine Loess Area In Qinghai

In this study,the health status of artificial ecological public welfare forest in three typical small watersheds of different afforestation periods in the high cold loess region of Qinghai Province was evaluated,and the measures to improve the health status were put forward.18 evaluation indexes including forest soil quality,forest structure,forest stability and forest community productivity were selected to construct the evaluation of artificial ecological public welfare forest In the price index system,the weights obtained by AHP and entropy method were combined,and the combination weight was taken as the final weight of evaluation index.The health index of artificial ecological public welfare forest was obtained by using comprehensive index method.Five health grades including unhealthy [0,0.40],subhealth [0.40,0.55),healthy [0.55,0.70),good health [0.70,0.85] and high-quality health [0.85,1] were divided into five health grades The results showed that:(1)the area percentages of unhealthy,sub-health,healthy,good health and high-quality healthy forests were 38.8%,42.2%,12.4%,6.5% and 0% respectively,and the overall health index of the artificial ecological public welfare forest was 0.45(2)the area percentage of unhealthy,sub-health,healthy,good health and high-quality healthy forests in the small watershed of ta'ergou were 0%,6.3%,68.0%,14.3% and 11.4% respectively,and the overall health index of the artificial ecological public welfare forest was 0.66,so the artificial ecological public welfare forest was in a healthy state;(3)Yangjiazhai The area percentages of unhealthy,sub-health,healthy,good health and high-quality healthy stands in small watershed were 12.4%,60.5%,27.1%,0% and 0%,respectively,and the overall health index of artificial ecological public welfare forest was 0.49,so the artificial ecological public welfare forest in Yangjiazhai small watershed was in sub-health state;(4)using path analysis model,the average tree height and volume per unit area were forest stands Soil organic matter,coverage of shrub and grass,community structure and soil water content were the limiting factors affecting forest health.According to the results of health evaluation of artificial ecological public welfare forest,the number and area distribution of artificial ecological public welfare forest in different age groups and different sites,as well as the determination results of limiting factors,the measures to improve the health status of artificial ecological public welfare forest were put forward.