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1.
In Turkey, 99.9 % of the forest land belongs to the state, and according to the Turkish Constitution, the ownership of the state forests cannot be transferred to private parties or other non-state organizations. However, some permits have been granted to use and benefit from the state forests without transferring the ownership. One such is the private afforestation permit. Private afforestation aims to increase forest lands and the growing stock, to re-establish the deteriorating balance between soil, water, and plants, to improve the environmental value, and to provide income to natural entities. This study aims to identify the legal and administrative regulation dimensions of the land use policy on private afforestation in Turkey and to compare them with other successful international afforestation policies.The second part of this paper is a case study on the impact of the legal changes over time in private afforestation in the sample area. Interviews were conducted with participants in the program using questions addressing the socio-economic and cultural benefits of private afforestation along with their afforestation practices and problems. The overall conclusion of this survey was that private afforestation practice had contributed to the income level of the participants. Further, to increase the participation in the program, more public awareness was necessary and incentives to participate must be increased.  相似文献   
2.
城市自生群落具有重要的生态服务功能与潜力,但因其外貌不被公众所接受而难以在城市公共空间中应用。将群落生态学和设计学相结合,探索一种介入栽培植物对城市自生群落进行改良,最终形成具有一定美学价值的植物群落的途径。实验以植物群落设计美学原理和种间竞争原理为依据,向已经演替1年的城市自生群落中引入63种栽培植物,按照分层的方式对群落进行改良。3年的观测结果表明,有61.9%的栽培植物可以在城市自生群落中定居并建立优势,能对76.7%的自生植物起到抑制作用,使55.8%的自生植物消失。相比城市自生群落,改良后的群落美观度提高29.4%,公众接受度提高24%,群落的物种丰富度提高至2.29倍。相比一般的人工植物群落,改良后的群落可以节约58.2%的建植成本,降低83.9%的浇水成本和67.8%的除草成本。实验证明改良设计是一种可行的群落设计途径,能有效提高群落的物种丰富度和美学价值,同时让自然参与群落设计过程,实现人与自然的合作。  相似文献   
3.
通过对上海近30年的气候因子汇总分析,结合对上 海世博公园主要绿化树种生长状况调查和年度生物量计算,通 过典型相关性分析发现,极端高低温、强风和暴雨等5个气候 因子对树木的生长产生了不同程度的影响,有些因子严重阻碍 了树木的正常生长,成为障碍因子。经过10年的绿化实践验 证,上海世博公园对骨干树种的选择,以乡土树种为主,群落 结构较为稳定,且气候障碍因子对乡土树种的影响较小。在引 种外来树种时,采用气候相似植物区系法,结合植物耐寒、耐 热带图,把种源地划分为2个气候带和3个植物区系,并确定了 最南引种线,成功引种了红花槭等20种观花色叶乔木树种。  相似文献   
4.
Wildlife sightings are not always guaranteed. To address this risk, tour operators often offer a money-back guarantee as a refund mechanism. However, studies have overlooked the influences of such refund mechanisms on tourists' tour participation decisions and tourism revenue. We conducted choice experiments to examine the impact of such mechanisms using a case of Amami rabbit tourism in Japan. We found that the guarantee significantly influences the tourists’ decision-making and tour revenue. In particular, we found that the expected tourist participation rate and tour guide revenue vary drastically depending on the probability of the rabbit encounter. The maximum expected revenue from the tour with a 90% chance was about 20 times larger than that with a 10% chance. This indicates that conserving wildlife to maintain the sighting probability raises tour benefits, creating a win-win situation by balancing conservation and tourism development.  相似文献   
5.
Despite the significant effect that invasive species have on natural values, the number and extent of invasions continue to rise globally. At least three dominant reasons explain why policy development and implementation can fail: differences in managers’ mental models of invasive species management; cross-agency responsibility; and poor planning and management (i.e., planning–implementation gap). We used a case study of cross-agency management of gamba grass (Andropogon gayanus) in Australia to explore the differences in organizational staffs’ mental models of management. The gamba grass invasion in northern Australia is continuing to expand and associated effects are increasing; coordinated action across agencies is needed to manage the expansion. Our aim was to examine how staff would represent their mental models as a diagram that we could compare between individuals and groups. We used cognitive mapping techniques to elicit models of 15 individuals from across 5 organizations, represented as an influence diagram, which shows the interrelationships that define a system. We compiled the individual influence diagrams to create a team model of management that captures the common connections across participants’ diagrams. The team model revealed that education, science, legislation, enforcement and property management plans were perceived to be the most important management tools to control or eradicate gamba grass. The Weed Management Branch was perceived to have the most central role in gamba grass management, while other organizations were perceived to have specific roles according to their core business. Significant positive correlations (i.e., shared perceptions) were observed across half of the participants, indicating that the some participants have shared models that could be used as a starting point for discussing the team model, clarifying roles and responsibilities, and potentially building consensus around a shared model. Dominant opportunities for improvement identified by participants were better use of management tools, namely education and enforcement, better coordination and collaboration between agencies and increased resourcing. Our research demonstrates the value and validity of using influence diagrams to explore managers’ mental models and to create a team model that could serve as a starting point for improved cross-agency natural resource management.  相似文献   
6.
Natural vegetation enhances the value of agricultural landscapes for people and wildlife. However, the role of anthropogenic versus topographic factors in driving the extent of natural vegetation cover within agricultural lands at large spatial scales remains unexplored. I assessed the influence of anthropogenic and topographic variables on the extent of agricultural mosaics with high natural vegetation cover in the country of Turkey where a large extent of natural and semi-natural vegetation is maintained by traditional agriculture. GIS layers depicting human land use, elevation, slope, roads and population data were obtained and summarized at two spatial scales, within provinces and for 100 km2 grid cells covering the country’s entire agricultural land area. Average farm size was also obtained at province level. Hierarchical Partitioning was conducted to determine the independent effect of anthropogenic and topographic variables on the variation in agriculture with high natural vegetation. Slope had the largest independent effect on the variation in the proportion of agricultural mosaic with high natural vegetation cover. The extent of agricultural and settlement area also explained much of the variation in natural vegetation across both grid cells and provinces. The proportion of natural vegetation increased as human population and road density decreased across grid cells and as average farm size decreased across provinces. These results suggest that while topography is the primary driver of natural vegetation cover within agricultural mosaics in Turkey, the pressures associated with urban development and agricultural industrialization may also influence the cultural and wildlife value of agricultural landscapes.  相似文献   
7.
Southern African countries are increasingly dependent on natural beauty and wildlife for tourism. Conservation is essential for sustainable tourism, and is expensive, especially for threatened and endangered species. The current price of a species only takes into account its current usefulness, often leading to an underestimation of the value of wildlife. This paper contributes to debates on the value of endangered species by estimating current use and non-use values for the rhino, a species under extreme threat. Internationally, literature that values scarce and endangered species uses willingness-to-pay (WTP) to derive a value of the species. This paper uses WTP to determine the non-consumptive use value of the rhino based on three surveys, n = 1291, conducted in South Africa's Kruger National Park (KNP) and compare it to consumptive use values. Non-use and inter-temporal values are also estimated to provide a comprehensive valuation of the rhino. Non-consumptive use values per rhino in KNP are shown to exceed consumptive use values by a minimum of 50%. The threat of extinction is shown to be linked to institutional, market and policy failures. Policy implications include raising poaching fines, raising wildlife value awareness and incentivising the community benefits of wildlife conservation.  相似文献   
8.
[目的]文章以马铃薯关键生长期——结薯期为测量时点,以马铃薯和玉米、大豆、水稻为研究对象,开展高光谱曲线特征差异性研究。[方法]为更好地描述马铃薯与其他作物的光谱差异,创建高光谱反射率差异性指数、高光谱一阶导数差异性指数、高光谱红边幅值差异性指数、高光谱曲率差异性指数及高光谱植被指数差异性指数。[结果](1)马铃薯与玉米、大豆、水稻3种作物光谱曲线具有明显差异,马铃薯与玉米的反射率值在480nm附近蓝色波段位置差异最显著,差异性指数值为67.866%,与大豆、水稻的最大差异性指数值分别为49.068%、57.559%,均位于550nm附近绿色波峰位置;(2)作物光谱曲线经一阶导数变换运算,马铃薯与其他作物间的光谱差异被显著放大,在近红外波段放大程度最显著;(3)马铃薯与玉米、大豆、水稻高光谱曲率差异性指数最大值均位于波长750nm附近,差异性指数值分别为78.365%、63.471%、80.882%;(4)常用植被指数中,比值植被指数、增强型植被指数可显著区分马铃薯与玉米、大豆、水稻。[结论]差异性分析结果为农作物空间分布遥感识别提供了技术支撑。  相似文献   
9.
基于光能利用率模型的河南省冬小麦单产估算研究   总被引:2,自引:0,他引:2  
[目的]快速、准确估算空间尺度上作物产量,对于评价农田生态系统对气候变化的响应、制定科学合理的粮食政策、对外粮食贸易等具有重要意义。河南省冬小麦产量占全国1/4,准确估算河南省冬小麦产量对维护国家粮食安全具有重要作用。单产估算作为农作物估产中的关键技术,也是作物估产的难点之一。[方法]文章首先利用VPM(Vegetation Photosynthesis Model)估算冬小麦NPP(Net Primary Product),结合收获指数、冬小麦收获部分的含水量、含碳量、NPP分配到地上或地下部分比例等一系列符合该研究区的经验指数,进行河南省冬小麦单产估算研究,并分析了引起模拟误差的原因。[结果]模拟单产较实测单产低估4.4%(实测单产为6 810kg/hm~2,模拟单产为6 519kg/hm~2),但两者之间存在显著相关关系,两者相关系数的平方R2=0.70(n=50,p0.01)。通过与MODIS-GPP产品获得的冬小麦单产数据比较,基于VPM模型的模拟结果优于MODIS-GPP产品。[结论]基于VPM可快速、准确估算河南省空间尺度冬小麦单产,该方法具有较好的适用性。  相似文献   
10.
Despite the important role of Neglected and Underutilized Species (NUS) in diversifying agriculture, supporting traditional farming systems and improving food and nutritional security particularly in marginal lands, very little attention is being paid to their mainstreaming in national policies and institutions. Based on a detailed review of the regulatory frameworks governing the conservation, sustainable use and equitable sharing of benefits arising out of plant genetic resources and the circulation and registration of seeds and improved varieties, this paper discusses the extent to which the measures in place in India may favour or affect the conservation and use of NUS. In addition to these frameworks, in view of the major change realized by the 2013 National Food Security Act which has included coarse cereals in the country’s Public Distribution System (PDS), the paper also incorporates this latest policy in its analyses. A special focus is given to small millets, a group of species with unexploited economic and nutritional potential but extremely important for marginal communities’ food security and livelihoods. A set of policy recommendations and opportunities to explore are proposed to address the identified constraints with the purpose of creating a more supportive policy environment and enhancing the national capacity to promote NUS.  相似文献   
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