| Soil and water loss in hilly slope land is an important problem faced by geography,ecology and other disciplines,and is closely related to human economic and social development.Hedgerow is a strip shrub or herb planted along the contour line in a single or combined mode,which is an important means of ecological restoration in hilly slope land.The ecological environment in the hilly area of the Taihang Mountains is sensitive and fragile,the stability of the ecosystem is poor,and ecological problems such as soil erosion and land degradation have existed for a long time.It is still a national key control area of soil erosion.The study on soil and water conservation function of hedgerows on sloping land is helpful to control soil and water loss in Taihang Mountains,and can provide scientific basis for ecological restoration and sustainable economic and social development in mountainous areas.（1）Differences in physiological characteristics of hedgerows.The above-ground biomass of Mentha haplocalyx was the highest,and the above-ground biomass of Paeonia lactiflora,brocade lantern and Houttuynia cordata was lower,and Mentha haplocalyx was significantly higher than white peony,brocade lantern and Houttuynia cordata（p<0.05）.The underground biomass of Paeonia lactiflora was the highest and significantly higher than that of the other five hedgerows（p<0.05）.The total biomass of Mentha haplocalyx was the highest,and that of Physalis alkekengi and Houttuynia cordata were lower.The total biomass of Mentha haplocalyx was significantly higher than that of Physalis alkekengi and Houttuynia cordata（p<0.05）.The root-shoot ratio of Paeonia lactiflora was significantly higher than that of the other five hedgerows（p<0.05）.The water content of Houttuynia cordata,Physalis alkekengi and Eupatorium adenophorum was higher,and the water content of Paeonia lactiflora was the lowest.The water content of Houttuynia cordata and Physalis alkekengi was significantly higher than that of Paeonia lactiflora（p<0.05）.The transpiration rate of Eupatorium adenophorum leaves was the highest,while the net photosynthetic rate of Paeonia lactiflora and Mentha haplocalyx leaves was higher.（2）Hedgerows have the effect of regulating and storing soil moisture on the slope.The water storage capacity of Paeonia lactiflora and Mentha haplocalyx hedgerows is relatively high,while that of Eupatorium adenophorum hedgerows is relatively low.According to the analysis of various indexes of soil water storage capacity,the average soil bulk density between hedgerows was small,and the difference between the parallel positions of CK was large.The soil electrical conductivity on the hedgerow or in the hedgerow was higher than that under the hedgerow,while CK was lower than that under the hedgerow.The difference of average soil natural water content between hedgerow belts was small,and the average soil natural water content in the upper and middle belts of CK belt was 23.87%and 31.84%lower than that in the lower belt.Among them,the average soil natural water content in the Paeonia lactiflora belt was significantly higher than that in the other hedgerows and CK（p<0.05）.The average soil saturated water holding capacity in hedgerows was higher,while that in CK was lower,and that in Mentha haplocalyx and Paeonia lactiflora strips was significantly higher than that in Artemisia argyi and CK（p<0.05）.The average soil capillary water holding capacity of hedgerows was middle>lower>upper,and CK was lower>upper>middle.The soil capillary water holding capacity of six hedgerows was higher than CK.The average soil field capacity of the upper and middle hedgerow belts was 18.87%and 24.66%higher than that of the upper and middle hedgerow belts of CK,respectively.The soil field capacity of Paeonia lactiflora was significantly higher than that of Eupatorium adenophorum and CK（p<0.05）.（3）Hedgerows can stabilize soil structure and regulate soil nutrients.Among them,the ability of Mentha haplocalyx and Paeonia lactiflora hedgerows to stabilize soil structure is relatively high,while that of Artemisia argyi hedgerows is relatively low.Eupatorium adenophorum and Houttuynia cordata hedgerows have relatively high ability to regulate soil carbon and nitrogen,while Artemisia argyi and Physalis alkekengi hedgerows are relatively low.Analysis according to the indicators of soil retention capacity,the soil porosity of Mentha haplocalyx,Paeonia lactiflora and Eupatorium adenophorum is higher than that under the belt,while that of Artemisia argyi and CK is lower than that under the belt.The interception coefficient of soil sand in the hedgerow belt or in the hedgerow belt was basically higher than that of CK,among which the interception coefficient of soil sand in Paeonia lactiflora was the highest,and Artemisia argyi was the lowest.The soil water stability index of hedgerows was basically higher in the upper and middle zones than in the lower zone,and CK was characterized by middle zone>lower zone>upper zone.The soil water stability index of Mentha haplocalyx was higher,while that of Artemisia argyi and Houttuynia cordata was lower.The average soil erodibility index in the upper and middle hedgerows was 7.82%and3.71%lower than that of CK,respectively,and that in the upper and middle hedgerows of Paeonia lactiflora was significantly lower than that of Artemisia argyi and CK（p<0.05）.The average soil total nitrogen content on hedgerows was 4.53%higher than that of CK,with Houttuynia cordata being the highest(1.08g·kg-1)and Mentha haplocalyx being the lowest(0.73g·kg-1).The average soil organic carbon content in the upper and middle hedgerow belts was 17.57%and 8.02%higher than that in the upper and middle hedgerow belts of CK,and3.86%lower than that in the lower hedgerow belts of CK.The average soil organic carbon content in the upper and middle hedgerow belts of Eupatorium adenophorum was significantly higher than that in Artemisia argyi and Physalis alkekengi（p<0.05）.（4）There are differences in soil and water conservation functions of different hedgerows,and the causes are related to plant physiological characteristics.The comprehensive evaluation results of soil and water conservation function of hedgerows showed that:Paeonia lactiflora>Mentha haplocalyx>Physalis alkekengi>Houttuynia cordata>Artemisia argyi>Eupatorium adenophorum.The results of cluster analysis showed that the soil and water conservation function of Paeonia lactiflora was strong.The clustering distance of mint and houttuynia hedgerows is close,and the soil and water conservation function is medium;the hedgerows of Physalis alkekengi,Artemisia argyi and Eupatorium adenophorum are close to each other,and their soil and water conservation functions are weak.The difference in soil and water conservation capacity of different hedgerows may be related to the physiological characteristics such as belowground biomass,aboveground stem and leaf morphology and plant photosynthetic efficiency.The study found that the difference of hedgerow species significantly affected most of the indicators of soil and water conservation capacity,and there was a significant or extremely significant positive correlation between the physiological characteristics such as underground biomass and leaf net photosynthetic efficiency of hedgerows and the indicators of soil and water conservation capacity.Therefore,the hedgerows of Paeonia lactiflora and Mentha haplocalyx can be selected to prevent soil erosion and promote ecosystem restoration on the slope land of Taihang Mountains.They have strong adaptability to the environment of water and fertilizer shortage on the slope land,and the effect of soil and water conservation is obvious. |
PDF Full Text Request