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欲研究提高水稻作物上养分利用率的措施,则需要了解所施养分的去向及其对作物产量的影响。在亚洲水稻为主的耕作制中,保持和提高土壤肥力必须研究养分综合管理。充分利用土地上的已有资源可导致作物大幅度增产,故现在十分强调上壤 N 素及其管理。通过运用~(15)N 平衡技术和微气象学技术,在氮挥发的定量测定和反硝化损失的评价方面均已取得进展。现在人们对于控制水稻淹水特性的交互作用因素有了进一步的了解。淹水特性和风速一类大气参数很大程度上决定着水稻生态体系的养分气态损失过程。在定量研究 NH_3挥发损失方面,由于方法较为先进,故取得的进展比反硝化损失的定量研究方面更大。在 N 素综合管理方面,施用生物肥料和在禾谷类作物耕作制中种植绿肥等往往更有利于作物持续高产。在利用系统方法管理磷和钾养分方面也大有可为。例如,P 肥应主要施用在旱作、尤其豆科作物上,而非施用在水稻和小麦等禾谷类作物上。豆科绿肥除了 N 以外,还能提供 P 和 K。关于土壤中的养分平衡,特别是水稻不同部位不同浓度 K、Ca 和 Mg 之间的交互影响,我们还了解得很不够。在禾谷类作物集约耕作制下,缺 S 对作物生产的影响将变得日趋重要。在养分综合管理研究中,研究重点明确、且学科间交流增强的系统研究方法具有颇多益处。
To study ways to improve nutrient use efficiency in rice crops, one needs to know where the nutrients are being applied and how they affect crop yields. In the paddy-based farming system in Asia, integrated nutrient management must be studied to maintain and enhance soil fertility. Making full use of existing resources on the land can lead to a substantial increase in crop yield, the emphasis is now placed on the availability of N and its management. Through the use of ~ (15) N balance technology and micro-meteorology techniques, progress has been made in the quantitative determination of nitrogen volatilization and in the evaluation of denitrification losses. Now people have a better understanding of the interaction factors that control the flooding characteristics of rice. A series of atmospheric parameters, such as flooding characteristics and wind speed, determine to a great extent the nutrient-gas loss process in rice ecosystem. In the quantitative study of NH 3 volatilization losses, the progress made is greater than quantitative studies of denitrification losses because of the more advanced methods. In the context of N-integrated management, the application of biological fertilizers and the planting of green manure in the cropping systems of cereal crops are often more conducive to the continued high crop yields. There is also room for a systematic approach to the management of phosphorus and potassium nutrients. For example, P fertilizer should be applied primarily to dry crops, especially leguminous crops, rather than to cereal crops such as rice and wheat. Legume green manure in addition to N, but also provide P and K. We also know enough about the nutrient balance in soils, especially the interaction between different concentrations of K, Ca and Mg in different parts of rice. Under intensive farming of cereal crops, the impact of the lack of S on crop production will become increasingly important. In the research of integrated management of nutrients, there are many benefits to the systematic research methods that have a clear research focus and enhanced interdisciplinary exchanges.