Changing characteristics of soil pH and nutrients in vegetable greenhouses with different planting years in Southeast Tibet

作者 Cao Jianting; Yang Hong; Peng Yan; Zhang Xinjun

期刊 Journal of Northwest A & F University. Natural Science Edition , 2019,8:47

摘要 【Objective】This study elucidated the spatio-temporal characteristics of soil pH,conductivity and nutrient contents in greenhouse with different planting years to provide basis for sustainable use of conservation tillage soils.【Method】The vegetable sheds(2a,7aand 15a)and neighboring farmland soils at different planting ages in Nyingchi,Tibet were selected to measure soil pH,conductivity,and contents of organic matter,total nitrogen and available N,available P and available K at depths of 0-70cm.【Result】 Soil pH in vegetable greenhouses at different planting years and farmland gradually increased with the increase of soil depth.Soil acidity in vegetable greenhouses was more severe compared with farmland.Soil pH showed a V-shaped with the extension of planting years,and the smallest value of 5.080.22was found in 7agreenhouse.Soil conductivity decreased with the increase of soil depth,and surface aggregation was very significant.The vertical spatial variability of soil conductivity in vegetable greenhouses was more significant than in farmland.With the increase of planting years,the soil conductivity showed an increasing trend.In the early stage of vegetable greenhouse,the soil conductivity increased slightly.With the further extension of planting years,the soil conductivity increased more significantly.Soil organic matter,total nitrogen,and available nitrogen,phosphorus,and potassium contents decreased with the increase of soil depth.thesurface aggregationphenomenon in the vegetable greenhouse soil was more significant compared with the farmland.Soil organic matter,total nitrogen,and available N,P,and K contents increased with the increase of planting years,indicating significant accumulation of soil nutrients in vegetable greenhouses.Pearson correlation analysis showed that there was significant or extremely significant correlations between soil physical and chemical indicators.【Conclusion】During the production process of greenhouses in Bayi Town,southeastern Tibet,soil acidification was severe and soil surface nutrient accumulation was significant, resulting in environmental risks.It is advisable to appropriately control the application amount of chemical fertilizers in production management and to promote scientific fertilization for sustainable use of soil and ecological and environmental safety of greenhouses.