江苏省南通县农业资源的开发利用

本文根据江苏省南通县农业资源开发利用的现状,运用聚类分析法和模糊综合评判法,以乡为基本单元,将各乡划分为若干类。找出各类特征,明确开发整治的方向,制定开发利用的措施。     

湖北稻区农业资源特点和耕作方式新发展

本文论证了湖北稻区的资源具有三大特点。因此,认定该区应细分为:东南部早三熟双季稻区,中部单、双季稻两热三熟并存区,西北部单季稻两熟区。笔者认为,本区近10年发展麦稻、油稻稻、油稻减少肥稻稻、肥稻其主流是好的;讨论了紫云英大量减步后如何解决有机肥源匮乏的问题。主张今后应积极开发冬种,积极提倡冬作起厢分带间套,既稳定大宗作物的发展,又增产经作、饲料、蔬菜、绿肥,以提高稻田的经济效益。     

湖北稻区冬半年农业资源特点和冬季农业开发

本文论证了湖北稻区冬半年的农业资源及其特点,讨论了开发本区冬季农业的意义、发展方向及其关键措施。     

CONCENTRATIONS OF POLLUTANTS IN AGRICULTURAL RUNOFF1

ABSTRACT. .Eighteen rural lakes in Lubbock County were sampled on a routine basis following runoff-producing rainfall for a period of approximately eighteen months to determine whether or not runoff from intensively farmed agricultural areas contained significant concentrations of nitrates, phosphates, herbicides, or insecticides. An additional fifteen lakes lying within a triangle bounded by the cities of Plainview, Canyon, and Hereford, Texas, were sampled one time during the summer of 1969 to provide additional data regarding the nature and extent of the potential problem in an area with a different soil type and a slightly different cropping pattern. Based on results of detailed analyses of approximately two hundred samples of water collected from the lakes and an equal number of sediment samples collected from the same lakes at the same time, it appears that the concentrations of all chemical pollutants in runoff from agricultural lands in the High Plains are well below the allowable concentrations for drinking water.     

山地农业资源的时空性与持续利用研究：以陕西秦巴山地为例

山地是一种特殊的生态环境类型,受自然分异规律与人类经济活动的双重干预和影响,产生其特有的时空分异规律与层带组合格局。通过土地生态类型格局分析,可以揭示山地生态环境类型结构瑟功能的异质性和有序性,从而为探讨农业资源的时空性及其开发利用模式提供科学指导。     

我国农业县（市）绿色食品发展对策研究

发展绿色食品是实现区域可持续发展和发展生态农业的一条有效途径。本文分析了我国农业县（市）发展绿色食品普遍存在的问题,在此基础上提出了发展绿色食品的对策。     

长江流域商品粮基地建设与农业持续发展

长江流域横跨我国中亚热带,光、热、水气候资源及其时空组合优势明显,土地自然生产力较高。粮食生产在全国占有重要地位。但由于流域内山地比重大,人口稠密,人均土地资源偏少,在现有耕地资源有限和粮食市场不稳等的多重压力下,历史时期内形成的“南粮北调”正逐渐被“北粮南调”所取代。在分析长江流域粮食生产现状和近二十年来商品粮基地建设对粮食生产的促进作用的基础上,从流域经济持续发展角度,提出了发挥长江流域粮食生     

三峡库区山地可持续农业发展的问题与对策

三峡库区山地农业的发展与三峡工程的命运休戚相关。本文在详细分析库区山地可持续农业发展的主要制约因素的基础上,提出了库区山地可持续农业发展的主要途径     

常熟市农业资源的开发潜力与对策

该文就常熟市农业资源的实际出发,从改造中低产田、开发长江滩地、复耕零星废弃地、利用庭园空间、立体利用水面、开发杂草资源、加工植物蛋白饲料及发展棉田套作等8个方面的途径,评价了农业开发潜力,说明在经济发达地区的农业开发是大有可为的。文章提出了相应的实施对策。     

Importance of Sediment–Water Interactions in Coeur d’Alene Lake,Idaho, USA: Management Implications

A field study at Coeur dAlene Lake, Idaho, USA, was conducted between October 1998 and August 2001 to examine the potential importance of sediment–water interactions on contaminant transport and to provide the first direct measurements of the benthic flux of dissolved solutes of environmental concern in this lake. Because of potential ecological effects, dissolved zinc and orthophosphate were the solutes of primary interest. Results from deployments of an in situ flux chamber indicated that benthic fluxes of dissolved Zn and orthophosphate were comparable in magnitude to riverine inputs. Tracer analyses and benthic-community metrics provided evidence that solute benthic flux were diffusion-controlled at the flux-chamber deployment sites. That is, effects of biomixing (or bioturbation) and ground-water interactions did not strongly influence benthic flux. Remediation efforts in the river might not produce desired water-quality effects in the lake because imposed shifts in concentration gradients near the sediment–water interface would generate a benthic feedback response. Therefore, development of water-quality models to justify remediation strategies requires consideration of contaminant flux between the water column and underlying sediment in basins that have been affected by long-term (decadal) anthropogenic activities.