水田垦造中土壤有机质的提升及pH调整研究

Study on Soil Organic Matter Increment and pH Adjustment during the Reclamation Process of Paddy Fields

垦造水田对于提高耕地产能、保障国家粮食安全和维护生态环境健康具有重要意义,其中土壤质量提升极其关键。以粤北南岭山区韶关市A村旱地土壤为研究对象,详细分析土壤基本理化性质、重金属和有机污染物含量,判明其改造为水田过程中土壤质量提升的主要限制因子。在此基础上,设计调整有机质和pH等措施对土壤进行改良,并通过质量等别评价最终判定改造前后土壤质量变化特征,使其达到水田垦造要求。研究结果表明:该地区土壤重金属和有机污染物含量符合《土壤环境质量标准》,土壤有机质、pH和容重是该区域土壤进行水田垦造的最主要限制因子。通过表土剥离重构、施用有机肥45000 kg·hm^-2和黄腐酸钾7500 kg·hm^-2、以及播撒生石灰1500 kg·hm^-2能够有效提升该地区土壤有机质含量和pH值、并降低容重,使土壤具备垦造水田的基本条件。同时,经过改良,预计研究区可新增水田面积13.15 hm 2,国家级耕地利用等别提高至4等,省级耕地利用等别提高至10等。综上所述,土壤有机质和pH调整是耕地提质改造的必要手段,本研究为广东省耕地提质改造项目的有效实施提供重要的科学参考。

Paddy fields reclamation is of great significance for increasing the productivity of arable land,ensuring national food security,and maintaining the health of ecological environment.Taken the upland soil of village A in Shaoguan City,Nanling Mountain area,North Guangdong Province as the research object,this paper analyzed its basic physical and chemical properties of soil,contents of heavy metals and organic pollutants in detail,and identified the main limiting factors of soil quality improvement in the process of paddy field reclamation.Based on that,measures on soil organic matter increment and pH adjustment were designed to improve the soil,and the characteristics of soil quality before and after the reclamation were finally evaluated through quality evaluation,so as to meet the requirements of paddy field reclamation.The results showed that the contents of heavy metals and organic pollutants in the soil of this area were in accordance with the quality standard of soil environment,and the soil organic matter,pH and bulk density were the main limiting factors for paddy field reclamation in this area.The content of organic matter and pH value of soil in this area can be effectively increased and the bulk density can be reduced by stripping and restructuring the surface soil,applying 45000 kg·hm^-2 of organic fertilizer,7500 kg·hm^-2 of potassium fulvic acid and spreading 1500 kg·hm^-2 of quicklime,so that the soil in this area can be equipped with the basic conditions the reclamation of paddy fields.At the same time,it was estimated that 13.15 hm 2 of paddy field can be added to the research area after the reclamation,and the use grade of national-level cultivated land will be increased to 4,and that of provincial-level cultivated land will be increased to 10.In summary,soil organic matter increment and pH adjustment are the essential for improving soil quality during the reclamation process of paddy fields.This study provides an important scientific basis for the upgrading of arable land in Guangdong province.