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941.
Robert J. Farquharson Oscar J. Cacho John D. Mullen Graeme D. Schwenke 《Agricultural Economics》2008,38(2):181-192
Soil fertility decline and soil management for crop production are important economic issues for grain growers in north-eastern Australia. In that region, there is evidence of soil fertility decline which is attributed to past crop management practices. The questions addressed in this article are first, whether components of soil fertility can be improved by better management and second, by how much soil fertility would change. Soil fertility for crop production is considered in terms of soil organic carbon and nitrogen. A stochastic dynamic economic analysis of soil fertility management for wheat production is presented. A sequential analysis of first deriving the optimal nitrogen stock and application rates is followed by an assessment of tillage, stubble, and fertilizer strategies to obtain an optimal level of soil organic carbon. The recommended management practices are consistent with emerging management trends in the region. The derivation of optimal levels of soil fertility for agricultural purposes has other policy implications, which we discuss. 相似文献
942.
The establishment of deep-rooted perennial species and their processing for biomass-based products such as renewable energy can have benefits for both local and global scale environmental objectives. In this study, we assess the potential economic viability of biomass production in the South Australian River Murray Corridor and quantify the resultant benefits for local and global scale environmental objectives. We model the spatial distribution of economically viable biomass production in a Geographic Information System and quantify the model sensitivity and uncertainty using Monte Carlo analysis. The total potentially viable area for biomass production under the Most Likely Scenario is 360,728 ha (57.7% of the dryland agricultural area), producing over 3 million tonnes of green biomass per annum, with a total Net Present Value over 100 years of A$ 88 million. The salinity in the River Murray could be reduced by 2.65 EC (μS/cm) over a 100-year timeframe, and over 96,000 ha of land with high wind erosion potential could be stabilised over a much shorter period. With sufficient generating capacity, our Most Likely Scenario suggests that economically viable biomass production could reduce carbon emissions by over 1.7 million tonnes per annum through the production of renewable energy and a reduced reliance on coal-based electricity generation. Our analyses suggest that biomass production is a potentially viable alternative agricultural system that can have substantial local scale environmental benefits with complimentary global scale benefits for climate change mitigation. 相似文献
943.
Herbert Kyeyamwa Stijn Speelman Guido Van Huylenbroeck John Opuda-Asibo Wim Verbeke 《Agricultural Economics》2008,39(1):63-72
Farmers in sub‐Saharan Africa are constrained by large transaction costs associated with marketing of their livestock. However, transaction costs are often not taken into account in the analysis of factors hampering the development of livestock marketing in this region. This article empirically measures the influence of transaction costs on the offtake from cattle grazed on natural rangelands in Uganda. The study is based on the monitoring of 696 cattle transactions in three districts of Uganda from August 2004 to August 2005. The estimated models suggest that proportional transaction costs represented by the state of roads, distance to markets, and time taken to reach the market are important variables constraining market participation. In order to raise offtake from the national herd, it is essential to explicitly address these costs. One potential solution is collective action in marketing of livestock in which proportional and fixed transaction costs are reduced and shared among the group members. 相似文献
944.
Riccardo Scarpa John M. Rose 《The Australian journal of agricultural and resource economics》2008,52(3):253-282
We review the basic principles for the evaluation of design efficiency in discrete choice modelling with a focus on efficiency of WTP estimates from the multinomial logit model. The discussion is developed under the realistic assumption that researchers can plausibly define a prior belief on the range of values for the utility coefficients. D‐, A‐, B‐, S‐ and C‐errors are compared as measures of design performance in applied studies and their rationale is discussed. An empirical example based on the generation and comparison of fifteen separate designs from a common set of assumptions illustrates the relevant considerations to the context of non‐market valuation, with particular emphasis placed on C‐efficiency. Conclusions are drawn for the practice of reporting in non‐market valuation and for future work on design research. 相似文献
945.
Brian C. Briggeman Allan W. Gray Joshua D. Detre 《Review of Agricultural Economics》2008,30(2):370-378
Fresh Juice Incorporated (FJI) is in the process of determining whether it should launch a new fruit juice, Genetically Enhanced (GE) Juice. The GE Juice meets consumers' demands for a tasty, nutritious product and it would be the first new juice product in the last fifteen years. Before FJI decides to launch GE Juice, it must analyze the uncertainty surrounding market size, market share, and price of GE Juice. Finally, if FJI decides to launch GE Juice, then they must decide if they will bottle the juice themselves or outsource this process. This case teaches students how to discuss the strategic implications of launching a new product and develop a net present value and financial feasibility simulation model given limited information. 相似文献
946.
T. Efole Ewoukem O. Mikolasek J. Aubin M. Tomedi Eyango V. Pouomogne D. Ombredane 《国际农业可持续发展杂志》2017,15(2):208-222
In Sub-Saharan Africa, fish ponds are often an integral part of farming systems but have suffered from a lack of viability and sustainability. The present study aims to understand the strategies used by fish farmers to overcome economic and environmental constraints. In 2008 and 2009, fish farmers were surveyed in Central and Western Cameroon, and the fish production systems were classified by cluster analysis. Four broad types were identified according to the complexity of household operations. The development of extensive systems (large-scale and low-input) in rural areas of central Cameroon is induced mainly by abundant available land. For semi-intensive systems in both regions (small-scale and high-input in the Western Region, large-scale and high-input in peri-urban areas of the Central Region), horizontal integration is not sufficient to make fish production profitable and sustainable. More intensive fish farms tend towards vertical integration, in which farmers establish close links with input suppliers. Main causes of low productivity of semi-intensive systems (1–2?t/ha/yr) are both lack of knowledge of fish farming principles by farmers and lack of technical improvement by extension agents and researchers which need to consider the local complexity of farming systems to develop and intensify fish production. The adaptation of development strategies to socio-economic and environmental contexts is a necessity to hope for an increase in fish pond aquaculture production in Africa. 相似文献
947.
State‐contingent analysis of farmers’ response to weather variability: irrigated dairy farming in the Murray Valley,Australia
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Thilak Mallawaarachchi Céline Nauges Orion Sanders John Quiggin 《The Australian journal of agricultural and resource economics》2017,61(1):36-55
The agricultural sector is commonly regarded as one of the most vulnerable to climate change. Current understanding of the impact of climate change on this sector relies on the underlying assumptions about farmers’ possible responses to weather variability, including changes in crop choice, input combinations and land management practices. Many previous analyses rely on the implicit (and restrictive) assumption that farmers operate under a fixed technology set across different states of nature. This assumption, represented through stochastic production or profit functions, is commonly made but seldom tested and may understate farmers’ responses to climate change if state‐contingent production technologies are, in reality, more flexible. The potential for farmers to adapt production technologies in response to unforeseen events is at the core of the state‐contingent approach. Advanced in Chambers and Quiggin (2000), the theory contends that producers can manage uncertainty through the allocation of productive inputs to different states of nature. In this article, we test the assumption that farmers’ observed behaviour is consistent with the state‐contingent production theory using farm‐level data from Australia. More precisely, we estimate the milk production technology for a sample of irrigated dairy farms from the southern Murray–Darling Basin over the period from 2006–2007 to 2009–2010. 相似文献
948.
949.
Carmen Hubbard John Davis Siyi Feng David Harvey Anne Liddon Andrew Moxey Mercy Ojo Myles Patton George Philippidis Charles Scott Shailesh Shrestha Michael Wallace 《EuroChoices》2018,17(2):19-26
There is little doubt that Brexit would have significant implications for UK agriculture, a sector with strong trade links to the EU and strong reliance on CAP income support. This article reports preliminary results from employing a Computable General Equilibrium Model, a Partial Equilibrium Model and Farm Level Models to explore selected trade and domestic policy scenarios post‐Brexit. These allow for the estimation of changes in producer prices, production and farm incomes against a baseline scenario of continued EU membership. Under a Free Trade Agreement with the EU, agricultural impacts are relatively modest. By contrast, unilateral removal of import tariffs has significant negative impacts on prices, production and incomes. Adoption of the EU's WTO tariff schedule for all imports favours net importers (e.g. dairy) and harms net exporters (e.g. sheep). Given the strong dependence of most UK farms on direct payments, their removal worsens negative impacts of new trade arrangements and offsets positive impacts. Impacts vary across different types and sizes of farm, but also regionally. However, the period of adjustment to new trade and domestic policy conditions may prove very challenging for a large number of farm businesses. 相似文献
950.