Study On Health Status Of Armeniaca Vulgaris

Armeniaca vulgaris Lam.is one of the important tree species of wild fruit forest in Xinjiang.To maintain its health status and sustainable development ability is important for maintaining the ecosystem function of wild fruit forest and protecting wild fruit tree resources.In recent years,there were some problems of populations that hindered reproduction,reduced living capacity and increasing number of declining dead individuals,which is due to environmental changes,pests and diseases,human disturbance and other adverse factors.In order to accurately grasp the survival and health status of Armeniaca vulgaris population and clearify its sustainable development ability,this study used Yili wild fruit forest as the research area,located in the Huocheng County Daxigou,Xinyuan County Tuergen Xinghuagou,Gongliu County Xiaomohegou and Yilegedaigou.A total of 22 sample plots of 20×20 m~2were set up in wild fruits forests.Based on the structure of Armeniaca vulgaris population,natural regeneration ability and pest damage research,comprehensive evaluation of Armeniaca vulgaris population health for promoting the sustainable survival of Armeniaca vulgaris population and provide some theoretical references.The main research results are as follows:(1)Armeniaca vulgaris population structure health evaluation:Armeniaca vulgaris has both pure forest and mixed forest with wild apple,hawthorn and cherry plum.The average population density in the concentrated distribution area was 359±37 plants/hm~2,and the canopy density was 0.76.The average tree height,DBH and crown width were 6.61±2.22 m,20.53±8.18 cm and 5.60±1.71 m,respectively.There was no significant difference in tree height,but the crown width was larger.The canopy of the population structure in the density area showed a large cross overlap,and there was a significant shading and inhibition of growth.The age-class gradient structure of Armeniaca vulgaris was basically’spindle’,and the overall structure was unstable.It was mainly composed of 83.60%of mature middle-aged and older individuals,and seriously lacked young individuals(10.16%).The DBH growth of Armeniaca vulgaris in Xinghuagou,Mohegou and Yilegedaigou was in the middle state,while the DBH growth of Armeniaca vulgaris in Daxigou was in the inferior state,and the horizontal distribution pattern was evenly distributed.Comprehensive index evaluation method was used to preliminarily evaluate the structural health status of Armeniaca vulgaris population.It is urgent to carry out health care and structural recovery in areas with significant decline.(2)Analysis of regeneration ability of Armeniaca vulgaris:The results volume and the number of seeds in soil seed bank of Armeniaca vulgaris in Mohegou and Yilegedaigou were very low,but the proportion of aged seeds in soil layer was high.There were no saplings in the survey plots,and the regeneration was limited by provenance.The results of Armeniaca vulgaris in Xinghuagou were high,which could meet the needs of regeneration.The density of germinated seedlings reached 3.96±1.12 plants/m2 in the year.The survival of seedlings was difficult under the influence of lights,drought,pests,diseases,grazing and other factors in the forest land,and the establishment of young trees in the plot was limited.The Armeniaca vulgaris in Daxigou could germinated and built successfully,but the results were low.The density of germinated seedlings was 0.89±0.47 plants/m~2,and the density of built young trees was 880±254.20 plants/hm~2.The regeneration ability was not significant.High stand canopy density and weak understory light are extremely significant factors limiting regeneration.It is extremely difficult to achieve natural regeneration in the forest in the densely distributed areas of Armeniaca vulgaris by comprehensive evaluation.The natural regeneration is hindered by human disturbance in sparse woodland,open space and other areas,resulting in weak population regeneration ability.(3)Armeniaca vulgaris harm degree investigation:Diseases and insect pests are the main factors endangering the health of Armeniaca vulgaris population.The occurrence of diseases and insect pests in descending order is bacterial perforation,korean gecko,apricot bud gall,gummosis,almond bee and bark beetle,followed by human disturbance of tourism and grazing.Armeniaca vulgaris plants in Xinghuagou and Daxigou showed mild decline trend,Armeniaca vulgaris plants in Mohegou showed moderate reduction,Armeniaca vulgaris plants in Yilegedaigou showed severe decrease,and Armeniaca vulgaris population showed moderate lowering.The damage rates of Armeniaca vulgaris population was higher,and the damage degree was severer showed a declining trend.Based on the above research results,it can be preliminarily determined that the healthy status of Armeniaca vulgaris population was medium to low.The structure was unstable.The suitable area density for survival was large and the canopy density was high,and the regeneration in the forest land was limited.Under the site conditions outside the wild fruit trees have been distributed,it is more difficult to replant Armeniaca vulgaris.Armeniaca vulgaris in Gongliu County and Yilegedaigou was seriously damaged by pests and diseases,and the decline was significant.