黄河三角洲不同经济林土壤有机碳分布特征及改良土壤效应

[Objective]This study explores the soil organic carbon(SOC)distribution characteristics and soil C sink potential of different types of economic forests in the Yellow River Delta,as well as improving soil capacity,thereby clarifying the influence of economic forests on SOC,soil structure and fertility.[Method]Typical economic forest tree species(i.e.Ziziphus jujuba,Prunus persica var.nectarina,Pyrus bretschneideri and P.persica var.nectarina+P.bretschneideri)in the Yellow River Delta were selected as the research objects,and Populus alba farmland shelterbelt was selected as the control.Soil samples from the 0-20 cm and 20-40 cm soil layers of different treatments were collected to measure SOC,moisture physical and available nutrient indicators.[Result]1)The mean values of SOC content and density in the whole profile ranged from 3.85 g/kg to 10.76 g/kg and 0.97 g/kg to 3.00 g/kg.Among them,a single stand economic forest>P.persica var.nectarina+P.bretschneideri>P.alba,and the economic forest increased by 50.05%compared with P.alba.The soil water-holding capacity is shown as follows:P.persica var.nectarina+P.bretschneideri>P.alba>single stand economic forest;the content of soil available nutrient in P.bretschneideri soil was the highest,and P.alba was the lowest.2)The SOC content and density and soil water-holding capacity and available nutrient contents in the 0-20 cm soil layer are exceeded that of 20-40 cm.3)SOC content and density were significantly positively correlated with soil water content,storage rainfall,available phosphorus and available potassium content,and significantly negatively correlated with effective storage capacity and pH.[Conclusion]This study has found that SOC storage in P.bretschneideri is the best,followed by P.persica var.nectarina;P.persica var.nectarina+P.bretschneideri has the best soil water storage performance,followed by single stand;P.bretschneideri has the best effect on improving soil nutrients,followed by Z.jujuba;P.bretschneideri and P.persica var.nectarina+P.bretschneideri are the planting modes with good soil C sink potential and soil improvement effect in this area.This result can provide a certain degree of reference for study on soil C sink and soil quality improvement of economic forests in the Yellow River Delta region.