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旱地农业在宁夏农业中的地位及发展战略措施 总被引：2，自引：0，他引：2
论述了旱地农业在宁夏农业中的战略地位 ,针对宁夏旱地农业发展面临的资源环境脆弱、生态环境退化严重 ;农业产业结构不合理 ;人口过快增长的问题 ,从建立旱作节水农业技术体系 ,建设农林牧复合型旱地农业体系 ,建设特色旱地农业产业化体系 ,建设生态安全保障体系 ,建设旱地农业信息化管理与服务体系方面提出了宁夏旱地农业发展的战略措施 相似文献
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农史学界一般认为北方旱地农业"耕-耙-耢"相结合的耕作技术体系形成于《齐民要术》时期,然而《齐民要术》完整记载"耕-杷-劳"配合的耕作技术只出现三次,更多的地方只提"耕劳"而不提"杷"。因此,农史学界所持的观点还需要在深入分析《齐民要术》中"杷""劳"关系的基础上进行确证。《齐民要术》"杷""劳"关系的考察,有助于从理性上明确认识"耕-杷-劳"旱地耕作技术体系的形成,也有助于深化古代耕作制度史的研究。 相似文献
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基于我国农业规模化经营发展现状,从联耕联种的发展背景入手,介绍联耕联种模式的内涵与类型,阐明联耕联种模式的比较优势,并着重从托管主体、经营方式、依赖条件、适应范围和农村剩余劳动力等5个方面分析模式推广中存在的困境与难题,并提出相关政策建议,以期促进联耕联种模式的推广和发展。 相似文献
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黑龙江地域广阔,旱地面积大,农业生产主要依赖自然降水,是典型的旱作农业区。系统阐述了旱作农业的基本概念,发展旱作农业的意义和必要性。针对黑龙江省自然条件和生产实际,提出了发展旱作农业的可行性建议。 相似文献
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Long Term Effects of Farming System on Soil Water Content and Dry Soil Layer in Deep Loess Profile of Loess Tableland in China 
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下载免费PDF全文 Soil water is strongly affected by land use/cover in the Loess Plateau in China. Water stored in thick loessal soils is one of the most important resources regulating vegetation growth. However, soil water in the deep loess profile, which is critical for maintaining the function of the “soil water pool” is rarely studied because deep profile soil samples are difficult to collect. In this study, four experimental plots were established in 2005 to represent different farming systems on the Changwu Tableland: fallow land, fertilized cropland, unfertilized cropland, and continuous alfalfa. The soil water content in the 15-m-deep loess profiles was monitored continuously from 2007 to 2012 with the neutron probe technique. The results showed that temporal variations in soil water profiles differed among the four farming systems. Under fallow land, the soil water content increased gradually over time, first in the surface layers and later in the deep soil layers. In contrast, the soil water content decreased gradually under continuous alfalfa. The distributions of soil water in deep soil layers under both fertilized and unfertilized cropland were relatively stable over time. Thus farming system significantly affected soil water content. Seven years after the start of the experiment, the soil water contents in the 15-m-deep profiles averaged 23.4% under fallow land, 20.3% under fertilized cropland, 21.6% under unfertilized cropland, and 16.0% under continuous alfalfa. Compared to measurements at the start of the experiment, both fallow land and unfertilized cropland increased soil water storage in the 15-m loess profiles. In contrast, continuous alfalfa reduced soil water storage. Fertilized cropland has no significant effect on soil water storage. These results suggest that deep soil water can be replenished under the fallow and unfertilized farming systems. Dry soil layers (i.e., those which have soil water content less than the stable field water capacity) in the subsoil of the Changwu Tableland region can be classified as either temporary dry soil layers or persistent dry soil layers. Temporary dry soil layers, which typically form under annual crops, often disappear during wet years. Persistent dry soil layers generally develop under perennial vegetation. Even after removing the vegetation, persistent dry soil layers remain for several decades. This study provides information useful for the conservation and utilization of soil water resources in the Loess Tableland. 相似文献
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针对甘肃省旱作农业区年降水量少、季节分布不均匀、玉米生产中春旱严重的问题,采用田间试验的方法,研究了4种不同覆膜时期对旱地玉米生育期、土壤水分变化、水分利用效率、产量及经济效益的影响。结果表明,全膜双垄沟秋季覆膜优于顶凌覆膜、春覆膜和播前覆膜,即早覆膜优于晚覆膜。全膜双垄沟秋覆膜增加了降水利用率和水分利用效率,降水利用率为70.21%,产量为10039.34kg/hm2,比播前覆膜增产24.81%,水分利用效率30.19kg/(hm2·mm),比播前覆膜提高15.26%。全膜双垄沟秋覆膜可明显减少冬春季土壤水分的无效蒸发,增加土壤水分含量,使玉米的经济性状明显改善,增产增收,是旱作区进一步挖掘降水潜力和高产田创建的有效途径。 相似文献
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综合运用市场价值法和影子工程法等评价方法,估算出楚雄坝子2009年耕地生态系统服务价值,水田、旱地分别为209709.00、162967.66元/（hm2.年）。通过解译卫星遥感影像,发现1989～2009年楚雄坝子内城市扩张分别占用水田、旱地855、378 hm2。因此,2009年损失的耕地生态系统服务价值达2.41亿元。 相似文献
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针对全球气候变暖、我国水资源紧缺的问题,重点分析了目前我国热带、亚热带旱作农业的发展现状及存在问题,着重阐述了我国热带、亚热带地区发展旱作农业的意义,并对热区发展早作农业提出一些建议和对策。 相似文献
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MA Shi-ming Joachim Sauerborn 《中国农业科学(英文版)》2006,5(3):169-178
The history of the organic farming worldwide was reviewed in this paper. The development of the organic farming worldwide had gone through three stages, emergence, expansion, and growth. The contributors and their thoughts during the different development stages of the organic farming were briefly introduced. And the development status of the organic farming worldwide was reviewed from the aspects of land area under organic management, land area under organic management in percentage of total agricultural area, and world markets for organic products. Besides, the main existing problems for the further development of the world＇s organic farming, as well as the development status, problems and strategies of the Chinese organic farming were discussed. 相似文献
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在分析西吉县全膜双垄沟播技术在玉米生产中优势及存在问题的基础上,提出了加大旱作农业的扶持力度;加大种植业结构调整;大力推广机械化种植技术;强化管理和技术培训;选定品种,确定海拔;根据地力确定密度等旱作节水农业发展对策。 相似文献
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农艺农机结合是推进山西旱作节水农业现代化进程的突破口 总被引：4，自引：3，他引：1
通过分析山西农业机械化现状,指出了山西农业机械化存在的问题,并依据山西耕地类型和干旱气象特征,探讨了山西旱作节水农业对机械装备的需求特点。通过在研究、示范实践中将农艺与农机紧密结合的有益探索,明确了农艺农机结合是推进旱作节水农业现代化进程的突破口。 相似文献
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土地利用方式对径流中N、P输出的影响 总被引：2，自引：0，他引：2
不同土地利用方式对径流中N、P输出的影响有很大差异。降雨和地表径流是农田营养物质流失的主动力。该文综述了有关农用地N、P流失的研究现状,通过对农用地,特别是坡地降雨径流中N、P浓度的讨论,以及对旱地和水田中N、P流失量差异的比较,研究不同土地利用方式对径流中N、P输出的影响。最后,结合近年来国内外研究进展,提出了将来的研究重点。 相似文献
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世界有机农业发展的历史回顾与发展动态 总被引：20，自引：0，他引：20
简要回顾了世界有机农业的发展历程。将世界有机农业的发展历程分为产生、扩展和增长3个阶段，介绍了各阶段的代表人物和思想。从有机农业的面积、占耕地比例和有机产品的市场状况，综述了世界有机农业的发展动态，并讨论了世界有机农业进一步发展存在的主要问题。简述了中国有机农业的发展动态、问题和对策。 相似文献