Research On Comprehensive Supporting Technology For Rain Harvesting And Afforestation In The Front Mountain Belt Of The Northern Slope Of The Tianshan Mountains

The research objects are Rosa laxa Retz.,Prunus sibirica L.,and Hippophae rhamnoides subsp.turkestanica Rousi in the front mountain belt of the northern slope of the Tianshan Mountains.Under the two soil preparation methods of horizontal ditch and V-shaped pit,Set up three single-item water and moisture retention technologies,including grass covering cloth(A),bentonite water retention(B),and fulvic acid fertilizer retention(C).Carry out water-harvesting afforestation experiments without irrigation.The effects of different afforestation techniques on soil water content in afforestation and the responses of seedling growth indicators,physiological indicators and photosynthetic characteristics were analyzed.The best comprehensive supporting technologies for water harvesting and afforestation in the front mountain belt area of the northern slope of the Tianshan Mountains were screened out.The experimental research conclusions are as follows(1)In terms of afforestation effect,the afforestation survival rate and growth amount of horizontal ditch and V-shaped pit preparation are similar.The single-item water and moisture conservation technology is preferred to choose the grass covering cloth to ensure a higher afforestation survival rate and growth.Comprehensive water and moisture retention technology,grass-covering cloth + bentonite + fulvic acid is the best,followed by grass-covering cloth + bentonite(suitable for R.laxa,H.rhamnoides)or grass-covering cloth + fulvic acid(suitable for P.sibirica).(2)In terms of physiological indicators,water and moisture conservation technology can reduce the soluble protein,proline,peroxidase activity,malondialdehyde content and increase chlorophyll content in seedling leaves to varying degrees.The difference between the two land preparation methods is not obvious;The single-item water and moisture retention technology is covered with grass-proof cloth,and the comprehensive technology is covered with grass-proof cloth + bentonite + fulvic acid,which can effectively reduce the drought stress of seedlings,followed by grass-proof cloth + bentonite(suitable for R.laxa,H.rhamnoides)Or covered with grass cloth + fulvic acid(suitable for P.sibirica).(3)In terms of photosynthetic indicators,The soil preparation method had no significant influence on the photosynthetic indexes of the three seedlings;Different water and moisture conservation techniques had different effects on the photosynthetic indexes of the three tree species.In the single technology,the effect of A treatment on plant photosynthetic index was significantly higher than that of B+C treatment;In the comprehensive technology,A+B treatment has obvious effects on the photosynthesis of R.laxa and H.rhamnoides.A+C treatment had a significant effect on P.sibirica,and A+B+C treatment was the best.(4)In terms of hormone indicators,The soil preparation method had no significant effect on the hormone content of the three seedlings;In terms of water conservation and moisture conservation technology,A treatment and A+B+C treatment can effectively alleviate the drought stress of afforestation seedlings under non-irrigation conditions.Thereby reducing the content of abscisic acid in seedling leaves and increasing the content of gibberellin,indole acetic acid and zeatin riboside;Among the combination measures,A+B treatments had obvious effects on the hormone contents of R.laxa and H.rhamnoides,and A+C treatments had obvious effects on P.sibirica.(5)According to the technical regulations of afforestation and cost-minimization analysis,This study identified technologies in the mountain belt area in front of the northern slope of the Tianshan Mountains,afforestation techniques for two species of R.laxa and H.rhamnoides(V-shaped pit + grass-proof cloth +bentonite,V-shaped pit + grass-proof cloth).two kinds of P.sibirica afforestation techniques(V-shaped pit+ grass-proof cloth,V-shaped pit + bentonite).