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11.
Maize is one of the major staples and cash crops for many Tanzanians. Excessive volatility of maize prices destabilises farm income in maize‐growing regions and is likely to jeopardise nutrition and investment in many poor rural communities. This study investigates whether market reform policies in Tanzania have increased the volatility of maize prices, and identifies regional characteristics that can be attributed to the spatial price volatility. To achieve the objectives, an autoregressive conditional heteroskedasticity in mean (ARCH‐M) model is developed and estimated in this study. Results show that the reforms have increased farm‐gate prices and overall price volatility. Maize prices are lower in surplus and less developed regions than those in deficit and developed regions. Results also show that the developed and maize‐deficit regions, and regions bordering other countries have experienced less volatile prices than less developed, maize‐surplus and non‐bordering regions. Our findings indicate that investments in communication and transportation infrastructures from government and donor countries are likely to increase inter‐regional and international trade, thereby reducing the spatial price volatility in Tanzanian maize prices in the long run.  相似文献   
12.
While it is often recognised that agricultural technology adoption decisions are intertwined and best characterised by multivariate models, typical approaches to examining adoption and impacts of agricultural technology have focused on single technology adoption choice and ignored interdependence among technologies. We examine farm‐ and market‐level impacts of multiple technology adoption choices using comprehensive household survey data collected in 2010/11 and 2012/13 in Ethiopia. Economic surplus analysis combined with panel data switching endogenous regression models are used to compute the supply shift parameter (K‐shift parameter), while at the same time controlling for the endogeneity inherent in agricultural technology adoption among farmers. We find that our improved technology set choices have significant impacts on farm‐level maize yield and maize production costs, where the greatest effect appears to be generated when various technologies are combined. The change in maize yield and production costs results in an average 26.4% cost reduction per kilogram of maize output (the K‐shift parameter). This increases the producer and consumer surpluses by US$ 140 and US$ 105 million per annum, respectively. These changes in economic surplus help to reduce the number of poor people by an estimated 788 thousand per year. We conclude that deliberate extension efforts and other policies that encourage integration of technologies are important for maize technologies to yield their full potential at both farm and market levels.  相似文献   
13.
This study analyses the economics of conservation tillage (CT) with respect to its effect on maize yield and chemical fertiliser, herbicide, and female and male labour demand. We estimate production and input demand functions using seemingly unrelated regressions on plot‐level cross‐sectional farm household data collected in the north‐west of Ethiopia. A two‐step control function is applied to address potential endogeneity bias due to the inclusion of the CT adoption decision as an explanatory variable. Our results show that CT increases maize yield and chemical fertiliser demand. Additionally, the results show that the adoption of CT reduces female and male labour required for crop production. However, this is achieved through the increased use of herbicides, which might have an undesirable health and environmental effects.  相似文献   
14.
We estimate the perceived costs of legal requirements (‘coexistence measures’) for growing genetically modified (GM) Bt maize in Germany using a choice experiment. The costs of the evaluated ex‐ante and ex‐post coexistence measures range from zero to more than €300 per measure and most are greater than the extra revenue the farmers in our survey expect from growing Bt maize or than estimates in the literature. The cost estimates for temporal separation, the highest in our evaluation, imply that the exclusion of this measure in Germany is justified. The costliest measures of the ones that are currently applied in Germany are joint and strict liability for all damages. Our results further show that neighbours do not cause a problem and opportunities for reducing costs through agreements with them exist. Finally, we find that farmers’ attitudes towards GM crops affect the probability of adoption of Bt maize. Our results imply that strict liability will deter the cultivation of Bt maize in Germany unless liability issues can be addressed through other means, for example, through neighbours agreements.  相似文献   
15.
During the past 15 years, there has been a considerable increase in highland maize farming in Nan, a province in northern Thailand. The increase in farming area causes an excessive forest encroachment and environmental problems, e.g. soil degradation, landslide, and pesticide contamination. This research explores the mechanism and factors which drive a sustainable transformation from highland maize farming to reforestation. We survey 107 farmers in Nammeed and Sopsai watersheds in where the reverses of growing trend of deforestation in Thailand have been observed. Comparative statistical analysis and regression are used to analyse factors affecting farmer’s decisions and compare differences between the two sites. We find that the fundamental mechanism driving a sustainable transformation from highland maize farming to reforestation comprises 3 pillars. These are 1) realization of adequate economic, health or environmental benefits derived from the alternatives; 2) a sense of belonging and attachment towards the forest and 3) effective enforcements of communal rules and regulations. While natural transformation in Nammeed area highlights the roles of flatland as key driver of the change, subsidy schemes can supplement the transformation during transitional period as seen in Sopsai area.  相似文献   
16.
Faidherbia albida is a tree species indigenous to semi-arid regions of Africa that reportedly substantially increases maize (Zea mays) yields in its immediate vicinity. In southern Zambia, F. albida is widely used in indigenous maize farming systems and this has apparently increased over the past two decades. Using a combination of interviews, group meetings, and observations, this study sought to understand why this species seems to have recently been embraced, while other technological innovations apparently have not. We observed a bimodal age distribution of the trees in agricultural fields and posit that the missing cohorts were removed as weeds as a result of evolving notions of what constituted modern farming practices in the emerging maize economy. With subsequent research and social promotion of the beneficial effects of F. albida, farmers now allow the trees to grow in their fields. A holonic analysis points to the important relationship of F. albida to contexts that shaped past and current uses of the tree by farmers on the Tonga Plateau: information, maize, cattle, land tenure, and government policy. Advice promulgated by social promotion activities took root in farmer knowledge contexts because of positive regard for F. albida and timeless injunctions against cutting mature specimens. Furthermore, cultivation of the tree was highly compatible with other important contexts in which farmers operate. However, our research also revealed the potential for adoption of the tree to create new tensions arising from the strong gendering of work and crops in the region.  相似文献   
17.
18.
Kenya is a globally recognized maize “success story.” As the overall percentage of maize farmers growing hybrids tops 80% and the seed industry matures, the slow pace of hybrid replacement on farms, and the continued dominance of the seed industry by Kenya Seed Company, may dampen productivity. Our econometric analysis identifies the factors that explain farmer demand for hybrid seed, and the age of hybrids they grow, considering hybrid seed ownership. Male‐headed households with more education, more assets, and more land plant more hybrid seed. Scale of seed demand per farm is differentiated by agroecology. We find a strong farmer response to the seed‐to‐grain price ratio, which we interpret as evidence of a commercial orientation even on household farms. However, despite the dramatic increase in the number of hybrids sold and the breadth of seed suppliers as seed markets liberalize, an older hybrid still dominates national demand.  相似文献   
19.
This study examined the acceptability and perceptions of traditionally prepared maize meal porridge, cooked from commercial roller-mill white maize meal and hammer-mill white and yellow maize meal (with and without fibre), among female Tsonga consumers in Giyani in Limpopo Province, South Africa. The study used sensory evaluation tests, followed by focus group discussions to gather supportive information about consumer attitudes, perceptions and practices regarding the consumption of maize meal porridge prepared from these maize meal types. Giyani consumers preferred commercial roller-mill white sifted fortified and white super-fortified maize meal, but, contrary to popular belief, were also willing to accept hammer-mill yellow maize meal, mainly for its nutritional value.  相似文献   
20.
能源短缺困扰世界经济的发展,许多国家纷纷调整能源政策,寻找矿物质能源的替代产品.玉米作为集粮,经、饲为一体的经济作物,研发燃料乙醇作为能源替代品,得到了世界各国的普遍关注和重视.  相似文献   
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