都江堰市不同农用地利用方式下土壤肥力质量动态变化特征研究

Study on Dynamic Change Characteristics of Soil Fertility Quality under Different Agricultural Land Use Patterns in Dujiangyan City

通过对都江堰市崇义镇大桥村、青城山镇赤城村和向峨乡石花村农用地进行定点监测,选取了水田、旱地、果园、菜地4种主要农用地利用方式,分析了2020—2022年不同农用地利用方式下土壤肥力质量的动态变化特征,为都江堰市农用地持续利用提供了数据支持。结果表明,2020—2022年不同农用地利用方式下土壤中的全氮、碱解氮、全钾、速效钾、全磷、有效磷含量均值大小均表现为菜地>果园>水田>旱地。土壤有机质整体呈上升趋势,监测样点间差异小,其中旱地变化幅度最大,3 a提高了2.90%;土壤全氮和碱解氮含量无明显差异,其中菜地氮素含量最高;菜地和果园土壤全磷和有效磷含量均明显高于水田和旱地,且样点间差异较大;2021—2022年水田和旱地土壤速效钾含量明显提高,2020—2021年差异不明显,且样点间差异较小。鉴于此,建议研究区增加有机肥的投入,提高土壤肥力;继续推广秸秆还田,高肥力的土壤一年还田一茬,维持土壤有机质的稳定,中低肥力的土壤可以两年还田三茬,同时还田时应配施氮肥,调整土壤碳氮比,防治秸秆腐烂与作物生长争氮。

Based on the fixed-point monitoring of agricultural land in Daqiao Village,Chongyi Town,Chicheng Village,Qingchengshan Town and Shihua Village,Xiang’e Township,Dujiangyan City,this paper selects four main land use patterns:paddy field,dry land,orchard and vegetable land,and analyzes the dynamic changes of soil fertility quality under different agricultural land use patterns from 2020 to 2022,so as to provide data support for the sustainable use of agricultural land in Dujiangyan City.The results showed that under different agricultural land use patterns,the contents of total nitrogen,alkali-hydrolyzed nitrogen,total potassium,available potassium,total phosphorus and available phosphorus in soil from 2020 to 2022 were vegetable land>orchard>paddy field>dry land.The soil organic matter showed an overall upward trend.The difference among the monitoring samples was small,and the dry land changed the most,with an increase of 2.90%in 3 years.There was no significant difference between the content of total nitrogen and available nitrogen in soil,among which the nitrogen content in vegetable land was the highest.The contents of total phosphorus and available phosphorus in vegetable land and orchard soil were significantly higher than those in paddy field and dry land,and the difference among sample points was large.From 2021 to 2022,the contents of available potassium in paddy field and dry land increased significantly.The difference between 2020 and 2021 was not significant,and the difference among sample points was small.Therefore,it is suggested to increase the input of organic fertilizer in the study area to improve soil fertility,continue to promote straw returning to the field,high-fertility soil returning to the field for one year to maintain the stability of soil organic matter,and medium-low-fertility soil can return to three crops for two years.At the same time,nitrogen fertilizer should be applied when returning to the field,adjust the soil carbon-nitrogen ratio,prevent straw decay and crop growth to compete for nitrogen.