过量施用磷肥和有机肥对土壤磷渗漏的影响

采用土柱培养的模拟试验方法,研究在不同磷水平土壤上大量施用磷肥和有机肥对土壤测试磷、土壤磷渗漏的影响及机理。结果表明,不同磷水平土壤施用磷肥和有机肥后,土壤CaCl2-P、Olsen-P和土壤渗漏液中可溶性磷均显著增加;单位量磷肥或有机肥所增加土壤各形态磷量随土壤磷水平的增加而增大;随着磷肥和有机肥用量的增加,单位量磷肥或有机肥所增加各形态磷量也逐渐增大,差异均达到显著和极显著水平;施用磷肥和有机肥土壤磷的最大吸磷量（Qm）和土壤磷吸持指数（PSI）逐渐减少,土壤磷的吸附饱和度（DPS）逐渐增加;单位量磷肥或有机肥所增加的土壤磷的吸附饱和度随着土壤磷水平的增加而增加。随磷肥和有机肥用量的增加,不同磷水平土壤磷的吸附饱和度逐渐增加、土壤磷的吸持指数下降、土壤磷的渗漏量逐渐增大;土壤磷渗漏量与土壤测试磷呈显著正相关;单位量磷肥或有机肥所增加的土壤测试磷随着磷肥或有机肥用量以及土壤磷水平的增加而增加。     

几种水生植物净化能力比较

通过模拟人工湿地的方法测试了7种高等水生植物对农村生活污水的净化能力,旨在筛选合适的湿地植物。结果表明:有植物处理系统对COD、总氮和总磷的去除效果明显高于无植物对照,植物本身的氮磷累积作用对氮的去除贡献为7%~63%,磷的去除贡献为12%~65%。多数测试植物对氮磷的富集量茎叶高于根系。不同植物的净化能力也有较大差异,从强到弱的顺序依次为芦竹>荻>菖蒲>芦苇>水生鸢尾>千屈菜>野慈姑。聚类分析结果显示这7种植物明显分为3类,其中,芦竹单独为一类,此类植物净化能力强;菖蒲、芦苇和荻为一类,此类植物净化能力较强;水生鸢尾、千屈菜和野慈姑为一类,此类植物净化能力较弱。     

Partial organic substitution weakens the negative effect of chemical fertilizer on soil micro-food webs

Soil biotic communities play vital roles in enhancing soil nutrient cycling and soil fertility. Long-term excessive nitrogen(N) application is disadvantageous to the stability of soil food webs and affects arable soil health and sustainable utilization. Proper organic substitution is essential to improve soil health and alleviate the disadvantages of excessive chemical fertilization. However, the biological effects of various organic amendments on soil micro-food webs are poorly understood. In o...     

Dynamics of organic carbon and nitrogen in deep soil profile and crop yields under long-term fertilization in wheat-maize cropping system

Soil organic carbon(SOC) and nitrogen(N) are two of the most important indicators for agricultural productivity. The primary objective of this study was to investigate the changes in SOC and N in the deep soil profile(up to 100 cm) and their relationships with crop productivity under the influence of long-term(since 1990) fertilization in the wheat-maize cropping system. Treatments included CK(control), NP(inorganic N and phosphorus(P) fertilizers), NPK(inorganic N, P and potassium fertilizers),...     

不同钾肥施用水平对木薯产量影响试验初报

为探索不同钾肥施用水平对木薯产量的影响,笔者在藤县进行同量基肥、不同量钾肥追肥施用的研究试验。试验结果表明：追施不同量的钾肥均能增加木薯的产量,但对作物的农艺性状基本无影响;从综合效益出发,以追施氯化钾225kg／hm^2产生的综合效益最好。     

硅钙肥在水稻上的应用效果试验初报

在水稻采用配方施肥的基础上,结合施用硅钙肥,试验结果表明：加施硅钙肥,能显著提高水稻抗纹枯病、穗颈瘟能力,增强水稻抗倒伏性,比常规施肥每667m2增产78.5kg,增产18.9%,增收113元,以每667m2施50kg为宜,施用方法全部作底肥。     

生物有机肥配施硅钙钾镁肥对西瓜产量、品质及土壤养分的影响

为科学减少化肥用量,改善土壤结构和环境,研究生物有机肥和硅钙钾镁肥对作物生长和改善土壤养分方面的作用,以‘L600’小果型西瓜为研究对象,设置生物有机肥配施硅钙钾镁肥并减少底肥化肥用量等4个处理,以常规施肥作为对照,研究上述肥料对西瓜产量、品质及土壤养分的影响。结果表明：生物有机肥配施硅钙钾镁肥与常规施肥相比,产量提高8.05%,心糖含量提高13.08%,边糖含量提高5.77%,维生素C含量提高18.57%,总酸含量降低31.25%、硝酸盐含量下降18.22%。两种肥料对改善土壤环境具有积极作用,土壤pH、有效磷、速效钾含量对比常规施肥明显升高。在此条件下减少底肥化肥施用,能够保证西瓜产量和品质,是一种有效的减量施肥方法。     

我国滴灌创新发展综述

我国是农业大国,农业作为用水大户,迫切需要大力推广节水灌溉技术。滴灌技术及设备是我国节水灌溉的重要组成部分,也是较早引入我国的节水灌溉模式。我国滴灌技术及设备走过了引进消化、示范推广、自主创新的发展阶段,为我国节水农业的发展做出了重要贡献。回顾了我国滴灌事业的创新发展历程,提出了发展区划及建议。     

Nitrogen application affects maize grain filling by regulating grain water relations

Grain water relations play an important role in grain filling in maize. The study aimed to gain a clear understanding of the changes in grain dry weight and water relations in maize grains by using hybrids with contrasting nitrogen efficiencies under differing nitrogen levels. The objectives were: 1) to understand the changes in dry matter and percent moisture content(MC) during grain development in response to different nitrogen application rates and 2) to determine whether nitrogen application...     

Characteristics of lodging resistance of high-yield winter wheat as affected by nitrogen rate and irrigation managements

High yields of wheat are mainly obtained through a high level of nitrogen and irrigation supplementation.However,excessive nitrogen and irrigation supplication increase the risk of lodging.The main objectives of this work were to clarify the capacity of lodging resistance of wheat in response to nitrogen and irrigation,as well as to explore the effective ways of improving lodging resistance in a high-yield wheat cultivar.In this study,field experiments were conducted in the 2015–2016 and 2016–20...