Research On The Adaptability Of Apocynum Venetum L. To The Slopes Of Different Gradient In The Quarry

Abandoned quarries are a kind of abandoned mines,and the site conditions are relatively harsh.During mining,a large number of gravel slopes are formed,which restricts the normal growth of plants.Therefore,vegetation restoration on the slopes of the quarry has become the focus and difficulty of the ecological restoration of the entire quarry.The selection of plant species is very important for the ecological restoration of the quarry slope.Apocynum venetum L.has strong ecological adaptability and adversity resistance.To explore its adaptability to the slopes of different slopes of quarries in order to understand its restoration potential.It is useful for promoting the ecological restoration of Apocynum venetum in quarries.The application in this field has important theoretical and practical significance.The Wenxi Quarry in Tangshan City,Hebei Province was originally a dolomite quarry for construction.The bedrock is exposed.It is a typical open-pit mining.This paper takes it as the research object and studies two kinds of planting in open field and transplanting.The growth status and physiological response of Apocynum venetum in different slope slopes of the quarry under the method,the results are as follows:(1)The average survival rate of Apocynum venetum was higher than the survival rate of direct seeding in open field.The survival rate of transplanting on 0° slope was as high as 91.1%,while the survival rate of direct seeding on other slope slopes was only 20%-30%.However,the average seedling rate of transplanting was lower than that of direct broadcast.Compared with the initial survival rate,the seedling rate of slopes with different slopes decreased slightly,but there was no significant difference.The seedling rate decreased slightly with the increase of slope,but all reached more than 70%,which indicates that the slope of the quarry The habitat can meet the basic needs of Apocynum venetum.(2)The increase in slope slope of the quarry has different degrees of inhibition on the growth of apocynum plant height,crown width,number of branches,and leaf area under the two cultivation methods(P<0.05),that is,the slope of the sample plot increases.Apocynum venetum had an inhibitory effect on the growth of the upper part of the ground;the slope of the slope promoted the growth of root system length and root-to-shoot ratio.In the 60° slope,the root length of the direct seedlings of Apocynum venetum was increased by 30.82% compared with the control.The increase is the largest.This shows that in terms of biomass allocation,Apocynum venetum will preferentially transfer biomass to the underground part and promote the growth of the underground part under slope adversity conditions.(3)With the increase of slope,the survival rate of Apocynum venetum under the two cultivation methods gradually decreased,indicating that the slope had a significant inhibitory effect on the survival rate of Apocynum venetum under the two cultivation methods(P<0.05).Compared with the two different cultivation methods,the overwintering survival rate of direct seedlings in the open field is slightly higher than that of transplanted seedlings at all slopes,and the overwintering survival rate of direct seedings in all slopes is above 80%;the transplanted seedlings have a slope of 75° The sample plot is 33.58% lower than the 0° slope,which is the largest drop in all treatments.In general,apocynum venetum has a higher possibility of establishing a long-term stable community on the slope of the quarry through live broadcast.(4)The increase of the slope slope has a significant inhibitory effect on the specific leaf area,relative leaf water content and chlorophyll content of Apocynum venetum(P<0.05).For example,in the autumn of 2020,the relative water content of the leaves of direct seedlings and transplanted seedlings in the open field is 38.93% and 34.73% of the 0° slope,respectively.The slope of the slope has an obvious promotion effect on the relative conductivity of the leaves(P<0.05).The relative conductivity of the leaves of the direct seedlings on the 75° slope in the open field reaches the maximum value of 54.51%,which is 131.86% of the 0° slope in the same period.Slope slope has a certain degree of promoting effect on the dry matter content,soluble protein content,MDA content and antioxidant enzyme activity of Apocynum venetum.The various changes of the above physiological indicators indicate that the slope produces physiological stress on Apocynum venetum,which in turn affects its normal growth.(5)According to the results of this study,the seedlings of apocynum venetum seedlings grow better than the transplanted seedlings,and the open field seedlings and the transplanted seedlings are more resistant to the quarry slope environment after one year of planting.Adaptability has increased.In the specific application of ecological restoration in the future,open-field live broadcasting can be combined with spraying,which is less costly and saves time and effort;transplanting is more controllable and has a higher initial survival rate.It can be used on the slope of a quarry with a large slope.Apply as appropriate.