Evaluation Of Initial Vegetation Restoration Effect Of Different Continuous Slope And Land Preparation Models For Damaged Mountains On Rocky Coast

In recent years,the rapid economic development in coastal areas has led to the over exploitation of mineral resources.There are a large number of damaged mountains in the mining area.Affected by sea breeze,precipitation and soil texture,landslides,rock collapse and other disasters occur frequently,endangering the safety of people's lives and property.Therefore,the ecological treatment of damaged mountains along the sea is imminent.In order to explore the impact of the continuous slope and land preparation mode of coastal damaged mountains on the initial restoration of vegetation,this paper selects the damaged mountains in Doulingzi Village,Yinjiahe mining area,Rizhao City as the research object,and selects five modes:secondary continuous slope mode(SM),fourth continuous slope mode(FM),low continuous slope mode(LM),medium continuous slope mode(MM)and high continuous slope mode(HM).In general,it is divided into two types:graded continuous slope and land preparation mode(SM,FM)and overall continuous slope and land preparation mode(LM,MM,HM),with the corresponding bare slope(CK1,CK2)as the control.Through the actual investigation in spring,summer and autumn and one-year laboratory experiment,by the analysis of the measured indicators of soil and vegetation,compare the impact of different models on the ecological restoration effect,study the internal relationship between different models and water holding capacity and soil factors,and evaluate the restoration effect of different models by principal component analysis.The results are as follows:(1)In terms of forest conservation rate,in general,the forest conservation rate of all slope continuation measures is more than 75%.In the model of graded continuous slope preparation,the mean value of forest preservation rate is FM(85%)>SM(75%);In the overall continuous slope land preparation model,the forest preservation rate is LM(82%)>HM(78%)>MM(77%).Among them,the forest preservation rate of FM is the highest.On the whole,there is no significant difference between the forest growth of the graded continuous slope and land preparation mode(SM,FM)and the overall continuous slope and land preparation mode(LM,MM,HM).In the experimental plot,the growth status of FM and LM was the best.(2)In terms of soil water holding capacity,compared with the control plot,each model effectively reduces the soil bulk density,optimizes the soil structure,improves the soil water holding capacity,and effectively improves the soil water holding capacity of the experimental plot.Among them,FM has the best water holding capacity,and its maximum water holding capacity is 642.4 t·hm~2.The loss of soil fixation is 970.735 t·hm^-2·A^-1.(3)In terms of soil consolidation,the soil erodibility in the test site ranges from 0.0270 to0.304.In the graded slope preparation mode,the soil erodibility of SM(0.0270)is the least;In the overall land preparation model,the soil erodibility of LM(0.0292)is the smallest.Compared with other models,SM and LM have more advantages in reducing soil erodibility.However,in the calculation of soil erosion modulus,the soil erosion modulus of FM is the smallest due to the influence of many factors.(4)The overall improvement effect of soil nutrients is good.Although the nutrients in the plot are poor,they show an upward trend.The soil nutrient content of each model is greater than CK.In the graded continuous slope land preparation model,the mean value of soil nutrient content is SM>FM;In the overall continuous slope land preparation model,the mean value of soil nutrient content showed LM>MM>HM.(5)In the calculation of the total value of soil consolidation and fertilizer conservation in the experimental site,the total value of soil consolidation and fertilizer conservation in the mode of graded continuous slope preparation is the highest on the whole.The total value of soil consolidation and fertilizer conservation of FM(3.8157 million yuan·hm^-2·A^-1)is the highest in the graded continuous slope land preparation mode.In the overall continuous slope land preparation mode,the total value of soil consolidation and fertilizer conservation of LM(2.7884million yuan·hm^-2·A^-1)with slow slope is the highest.To sum up,principal component analysis is used to comprehensively evaluate the repair effects of different modes,and the scores of the two modes are FM>SM respectively;LM>HM>MM.On the whole,the ecological restoration effect of graded continuous slope land preparation mode is higher than that of overall continuous slope land preparation mode.The results show that the soil and water conservation capacity of each model is greatly improved compared with the bare slope.In the slope with high altitude,the more compact the horizontal step distribution and the more soil and water conservation measures,the better the overall restoration effect;In the slope with low altitude,the gentler the slope is,the better the overall repair effect is.