摘要
开展2 a种植冬小麦-夏玉米的盆栽试验,研究污泥添加对石灰性土壤养分的影响,构建石灰性土壤中污泥添加量(0、3.75、7.50、37.5、75.0 t/hm^2)与有效磷之间的关系,确定磷素淋失的临界值。结果表明:污泥添加降低了石灰性土壤的pH值,但土壤有机质、全氮、碱解氮、全磷、有效磷、速效钾和土壤综合肥力指数随污泥添加量的增加呈增加趋势。试验期间,同年轮作季的污泥添加量相同时,玉米季土壤养分含量小于小麦季,且各养分随污泥施用年限的增加而增加,并与污泥的累积施用量之间存在显著(P<0.05)或极显著(P<0.01)的正相关关系。当污泥添加量大于等于37.5 t/hm^2时,土壤养分含量与未添加污泥处理相比差异显著(P<0.05)。污泥施用后该土壤磷素淋失临界值为有效磷质量分数28.57 mg/kg,其对应的污泥施用量分别为61.39 t/hm^2。研究可为在石灰性土壤中污泥的合理施用提供依据。
China’s urban sludge production is huge. The harmless and resource-based disposal of sludge is imminent.Agricultural use is an effective way to dispose sludge after its harmless treatment. Calcareous soil is one of the soil types widely distributed in arid and semi-arid areas of China. The purpose of this study was to clarify the impact of sludge on nutrient status and fertility characteristics of calcareous soil by continuously adding sludge on calcareous soil and to explore the critical value of phosphorus leaching from calcareous soil by adding sludge, so as to provide support to the rational application of sludge in this kind of soil. The typical calcareous soil in the north of China was selected as the object of this study, and the added amount of composted sludge was in accordance with the sludge application amount specified in the control standard for pollutants in agricultural sludge(GB4284-2018). The five treatments of sludge addition amount were designed: 0 t/hm^2(Control), 3.75 t/hm^2(H1), 7.50 t/hm^2(H2), 37.5 t/hm^2(H3), 75.0 t/hm^2(H4). The pot experiment of two years’ continuous planting of winter wheat and summer maize was carried out to analyze the annual and seasonal changes of soil nutrients after adding different levels of composted sludge. The integrated fertility index was determined by Nemero index method according to the relationship between soil available phosphorus Olsen-P and soluble phosphorus CaCl2-P. The relationship between sludge addition and phosphorus leaching critical value was determined. The results showed that the pH values of calcareous soil decreased with the addition of sludge, but the content of soil organic matter(OM), total nitrogen(TN), available nitrogen(AN), total phosphorus(TP), available phosphorus(Olsen-P), available potassium(AK) and soil integrated fertility index(IFI) increased with the increase of sludge addition. During the experiment, the content of soil nutrient in maize season was lower than that in wheat season when the sludge addition was the same in the same production season, and the nutrient content increased with the increase of sludge application years. There was a significant(P<0.05) or extremely significant(P<0.01) positive correlation between the nutrient content and the cumulative application amount of sludge. When the amount of sludge added in each growing season was more than or equal to 37.5 t/hm^2, the soil nutrient contents of treatments were significantly different from those of control treatments(P<0.05). The phosphorus leaching thresholds calculated by the above method was 28.57 mg/kg in calcareous soils. At this time, the amount of sludge application in the field was 61.39 t/hm^2. The addition of sludge improved the nutrient and fertility status of calcareous soil, and attention should be paid to the risk of soil acidification and phosphorus leaching caused by excessive application of sludge.
作者
常会庆
吴杰
王启震
焦常锋
朱晓辉
王浩
Chang Huiqing;Wu Jie;Wang Qizhen;Jiao Changfeng;Zhu Xiaohui;Wang Hao(School of Agriculture,Henan University of Science and Technology,Luoyang Key Laboratory of Symbiotic Microorganism and Green Development,Luoyang Key Laboratory of Plant Nutrition and Environmental Ecology,Luoyang 471000,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2020年第6期231-238,共8页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金面上项目(41571319)
国家重点研发计划(2017YFD0801300)。
关键词
养分
磷
淋失
污泥
石灰性土壤
临界值
nutrients
phosphorus
leaching
sludge
calcareous soils
critical values
