Agro-Ecosystems最新文献_第8页

Isoenzymatic variations in populations of Chenopodium album L. resistant and susceptible to triazines 三嗪类抗性和敏感性藜麦群体的同工酶变异

Agro-Ecosystems Pub Date : 1981-06-01 DOI: 10.1016/0304-3746(81)90011-1

J. Gasquez, J.P. Compoint

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引用次数: 38

Cropping and yields in agricultural systems of the north-eastern hill region of India 印度东北部山区农业系统的种植和产量

Agro-Ecosystems Pub Date : 1981-06-01 DOI: 10.1016/0304-3746(81)90012-3

O.P. Toky, P.S. Ramakrishnan

引用次数: 72

The study of vegetation 植被研究

Agro-Ecosystems Pub Date : 1981-06-01 DOI: 10.1016/0304-3746(81)90021-4

R. Misra

引用次数: 0

A comparison of productivities and energy values between slash and burn agriculture and secondary succession in the upper Rio Negro region of the Amazon Basin 亚马逊河流域上里奥内格罗地区刀耕火种农业与次生演替的生产力和能量值比较

Agro-Ecosystems Pub Date : 1981-06-01 DOI: 10.1016/0304-3746(81)90015-9

Christopher Uhl, Peter Murphy

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引用次数: 43

Plant strategies and vegetation processes 植物策略和植被过程

Agro-Ecosystems Pub Date : 1981-06-01 DOI: 10.1016/0304-3746(81)90020-2

R. Misra

引用次数: 55

China's agro-ecosystem 中国的农业生态系统

Agro-Ecosystems Pub Date : 1981-06-01 DOI: 10.1016/0304-3746(81)90013-5

Vaclav Smil

{"title":"China's agro-ecosystem","authors":"Vaclav Smil","doi":"10.1016/0304-3746(81)90013-5","DOIUrl":"10.1016/0304-3746(81)90013-5","url":null,"abstract":"<div><p>China's agro-ecosystem is circumscribed by two critical environmental constraints; relative shortage of arable land and frequent regional lack or surplus of moisture. Intensive cropping and intricate water controls were developed over the centuries to deal with these constraints, and they remain the cornerstone of China's farming today. Human and animal labor continues to be an essential input, as are large quantities of organic fertilizers. Reliance on biomass fuels will also stay high for the foreseeable future. Farming modernization has brought the greatest advances to water control (both irrigation and drainage) and nitrogenous fertilizer production. However, widespread shortages and qualitative deficiences of modern inputs will not be easily eradicated. Total food output during the past three decades just kept pace with the population growth and the one-sided stress on grain production led to insufficient supply of edible oils, fruits and above all, animal foods. Overall use of external energy subsidies (direct and indirect use of fossil fuels and hydro-electricity) is still rather moderate but bold modernization plans for the 1980's would raise it substantially, thus lowering the currently high output/input ratio. Whatever the actual pace of modernization, careful attention to China's deteriorating environment will be critical. Land losses and soil degradation, erosion, deforestation and pollution are assuming alarming proportions and the long-range development of China's farming in balance with its protected environment is finally being recognized as the precondition of sustainable success.</p></div>","PeriodicalId":100066,"journal":{"name":"Agro-Ecosystems","volume":"7 1","pages":"Pages 27-46"},"PeriodicalIF":0.0,"publicationDate":"1981-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0304-3746(81)90013-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82546055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Variability of stream water quality in some land management systems in the southern Kakioka Basin, Japan 日本Kakioka盆地南部一些土地管理系统中河流水质的变化

Agro-Ecosystems Pub Date : 1981-06-01 DOI: 10.1016/0304-3746(81)90014-7

T. Hirose, N. Kuramoto

引用次数: 6

Bird problems in agriculture 农业中的鸟类问题

Agro-Ecosystems Pub Date : 1981-06-01 DOI: 10.1016/0304-3746(81)90016-0

Richard Arnold

引用次数: 0

Heathlands and related shrublands. Descriptive studies, ecosystems of the world 9A 希斯兰和相关的灌木地。描述性研究，世界生态系统9A

Agro-Ecosystems Pub Date : 1981-06-01 DOI: 10.1016/0304-3746(81)90018-4

P. Jacquard