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951.
SOFTWARE REVIEWS     
software reviews are in this article MACATLAS . Number Cruncher Statistical System (NCSS) TRANSPRO FIRE-ROUTER  相似文献   
952.
农户的非农就业如何影响中国的土地流转?   总被引:1,自引:0,他引:1  
To clarify the impact of non-agricultural employment on rural land circulation in China,we built logit models using the Chinese Household Income Project 2013 dataset,which includes 18,948 household samples over 15 provinces,126 cities and 234 counties of China in 2013.We use the proportion of non-agricultural income,the proportion of non-agricultural laborers and non-agricultural fixed operating assets to reflect the degree of the households’dependence on agriculture,the degree of the households’laborers committed to non-agricultural employment and the stability of non-agricultural employment,respectively.The results show that the stability of non-agricultural employment is an important reason for farmers to transfer out their land,and an increase in non-agricultural income is the fundamental reason.The proportion of non-agricultural assets has the greatest impact on the decision to transfer land,followed by the proportion of non-agricultural income.Per unit increase in the non-agricultural income ratio has a stronger effect on the transfer-out decision than it does on the transfer-in decision,which is a 0.09 increase of the probability of transfer-out the land and a 0.07 decrease of the probability of transfer-in the land.In terms of regional differences,when considering the impact of non-agricultural employment on the land transfer-out decision,the impacts of non-agricultural income and labor force are the greatest in the Central region.The impact of non-agricultural assets is the greatest in the Eastern region.For the Eastern region,the decision to transfer out land is mainly affected by non-agricultural assets and the non-agricultural labor force,and the decision to transfer in land is mainly affected by non-agricultural assets.In the Central and Western regions,the decision to transfer out land is mainly affected by non-agricultural assets,non-agricultural income and the non-agricultural labor force,in that order.The decision to transfer in land in the Central region is not significantly affected by non-agricultural employment.The decision to transfer in land in the Western region is mainly affected by non-agricultural assets,non-agricultural labor force and non-agricultural income,in that order.We note that non-agricultural assets have a prominent impact on land transfer,which shows that the stability of non-agricultural employment has an important impact on land transfer decision-making.Vocational training for rural labor forces may be an effective means to promote stable non-agricultural employment and simultaneously facilitate rural land circulation,especially in Central and Western China.  相似文献   
953.
实施流域生态管理的长江中下游湿地保护探讨   总被引:4,自引:1,他引:4  
长江中下游地区湿地分布广泛且类型多样,是我国淡水湖泊分布最集中和最具有代表性的地区。为了从根本上解决长江中下游湿地利用面临的问题,实现湿地资源的可持续利用,保护湿地环境,解决区内上、下游用水的供需矛盾,实现水资源的优化配置,调动区域湿地保护的积极性和主动性,有必要遵循湿地流域分布规律,应用流域生态学最新理论与实践成果,进行流域生态管理。一方面,要从流域角度处理好几大江湖关系、蓄泄关系、湖垸关系和山湖(河)关系等;另一方面,在流域内建立统一协调机制,对流域湿地进行保护与合理利用、合理布局和统一规划;同时在保护的前提下,科学合理地利用长江中下游湿地资源,开拓新的生产力。  相似文献   
954.
中原经济区要建设成为全国"三化"协调发展示范区、全国重要的经济增长板块、全国综合交通枢纽和物流中心、华夏历史文明传承核心区,必须加快自主创新体系建设,提高自主创新能力,充分发挥科技创新的有力支撑作用。科技创新是一类开放的复杂巨系统,其专家系统、技术支撑系统、数据信息系统构成了科技创新体系的内核。通过加强人才培养、引进和使用,推进知识创新体系建设;狠抓科技投入和输出,推动技术创新体系建设;强化政府政策扶持引导,推进制度和管理创新体系建设,必然会推动区域发展由要素驱动向创新驱动转变,必然会推动和促进中原经济区的快速、全面、科学和可持续发展。  相似文献   
955.
The South African midwater trawl fishery targets adult horse mackerel Trachurus capensis. The bulk of the catch is taken by a single freezer-trawler, the biggest fishing vessel operating in South African waters. As fishing takes place off the south coast in ecologically sensitive areas, there are concerns about the potential impacts of this fishing operation on non-target species. Fishing behaviour and bycatch of this fishery from 2004 to 2014 were investigated by analysing observer records with regard to catch composition, volume and temporal and spatial patterns. The midwater trawl fishery was estimated to have caught 25 415 tonnes annually, with a bycatch of 6.9% of the total catch, by weight. There are species overlaps with various fisheries, namely the demersal trawl, small-pelagic, line, shark longline and squid fisheries, yet the total bycatch estimates from this fishery are generally small relative to catches taken in the target fisheries. Bycatch species with the highest average annual catches were chub mackerel Scomber japonicus, redeye roundherring Etrumeus whiteheadi, ribbonfish Lepidopus caudatus and hake Merluccius spp. Large-fauna bycatch species included sunfish Mola mola as well as a number of CITES II- and IUCN-listed species, such as Cape fur seal Arctocephalus pusillus, dusky shark Carcharhinus obscurus, smooth hammerhead shark Sphyrna zygaena and thresher sharks Alopias spp. The 97.9% observer coverage is high and the 6.9% bycatch rate low compared to other South African fisheries; however, due to the large size of the individual hauls (average of 46.3 t), the average sampling rate of 1.56% is low. Our analyses suggest that bycatch in the South African midwater trawl fishery has been lower than in other South African fisheries and similar fisheries elsewhere, but due to the combination of high catch volumes and low sampling rates, estimation errors for rare species are high and there is a substantial risk of incidental unmonitored bycatch of rare large fauna and aggregations of small fauna. This could be mitigated by spatio-temporal management of this fishery, to avoid fishing in high-risk areas, and the introduction of an electronic monitoring programme.  相似文献   
956.
云南省金沙江流域土壤流失方程研究   总被引:17,自引:2,他引:17  
云南金沙江流域是长江中上游水土流失最严重的区域。本项研究以“通用土壤流失方程”(USLE)为蓝本,运用小区实验等手段,综合分析了各个侵蚀因子,建立了云南金沙江流域土壤流失方程A=R·K·LS·c·P,并确定了方程中诸因子的求算方法和数值,以及该流域土壤允许流失量,为方程的应用提供了基本的技术数据。同时,还进行了方程的检验,方程计算值与小区实测值的相对误差在6.3%以下,表明该方程在实际应用中是可靠的。该方程的建立,可为云南金沙江流域预测预报土壤侵蚀,制定土地合理利用规划方案、水土保持措施和土地生态安全格局提供了一套可靠的科学方法和依据。  相似文献   
957.
将地质灾害治理工程项目管理及质量控制分为4个阶段:策划(可行性研究)阶段,准备阶段,施工阶段.验收审查阶段,分别阐述其管理及质量控制的重点内容。  相似文献   
958.
试论生态旅游的生态化道路--以自然生态旅游区为例   总被引:5,自引:1,他引:5  
生态旅游已成为当今世界旅游发展的潮流。然而,在生态旅游开发过程中,存在着众多的。非生态化”现象,尤其是在自然生态旅游区。分析当前自然生态旅游区旅游开发和建设中的“非生态化”现象,主要包括盲目开发,自然景观破坏严重;游客严重超载,生态环境受破坏;人造景观和设施泛滥,景观污染和趋同现象严重;管理和文明建设落后,文化景观功能退化或受损等。运用景观生态学原理和生态安全理论等,从景观功能分区、旅游生态管理容量、景观结构生态设计、景观生态安全格局构建、生态教育等方面提出自然生态旅游区的生态化道路。  相似文献   
959.
国内外旅游解说研究进展综述   总被引:14,自引:0,他引:14  
本文对国外旅游解说系统研究从旅游解说的起源、原理、内涵、框架、功能、受众类型、解说方式、解说规划等方面进行了全面的总结,综合了国内旅游研究的研究现状与趋势。寻找出国内解说研究与国外解说研究的差距,借此推动国内的旅游解说系统研究,从而更好地为旅游规划、旅游业的可持续发展和游客管理服务。  相似文献   
960.
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