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101.
Environmental pollution, food safety and health are closely linked. A key challenge in addressing the problem of food safety and protecting public health is building an integrated knowledge base to inform policy and strengthen governance. This requires breaking down the trans-departmental information barrier across the environment, food and health domains to ensure the effective flow of data and the efficient utilization of resources, and facilitate the collaborative governance of food safety. Achieving this will be crucial for the development of health and medical care in China in the era of big data. Currently, the information resources commanded by various departments are incomplete and fragmented. Data resources are also organized in vertical silos and there is a lack of data sharing within and across policy streams. To provide the basis for more effective integrated collection and analysis of data in future, this study summarizes the information resources of various departments whose work relates to interactions between environment, food and health, and presents measures to strengthen top-down design, and establish unified data standards and a big data sharing platform. It also points to the need for increased training of data analysts with interdisciplinary expertise.  相似文献   
102.
This article investigates the sources of vegetables consumed by farmers, their perception of pesticide-related food safety risks and the behaviors they engage in to protect themselves, and explores the implications for the social co-governance (shehui gongzhi) of food safety emphasized by China’s recent Food Safety Law. The research site is a county in Yunnan Province where vegetable growing is the major source of income and livelihood for local farmers. We surveyed 417 farmers and collected 776 vegetable samples from 377 surveyed farmer households and tested them for organophosphate and carbamate pesticide residues using PR-12N Rapid Detection Instrument for Pesticide Residues. The results showed that farmers know about the risks to food safety caused by pesticides used in vegetable growing and they purposely avoid these risks by mainly consuming vegetables planted in home gardens or private plots that use little or no pesticides. Vegetable samples from these private plots had the lowest positive rate of pesticide residues (6.10%), compared with vegetable samples from commercial farmland (13.73%) and markets (12.66%), and the difference was statistically significant (X2=9.69,0.005相似文献   
103.
Farmers are both the producers and consumers of food, and as such have a dual role in food safety: they both generate risks and are exposed to them. Based upon a survey of the food production and consumption habits of 140 farm households and long-term research in two villages in Yunnan province, this study found that rural families are highly dependent on the market for food production and consumption. In their role as consumers, farmers are aware of food safety risks and concerned about them, but their ability to protect themselves is limited. They do so primarily by avoiding certain products and growing as much of their own food as possible. At the same time, in their role as producers, farmers engage in practices, primarily the overuse and inappropriate use of fertilizer and pesticides, that are damaging to food safety and the environment. There is therefore a disconnect in their roles as consumers and producers that needs to be addressed if policy goals for improving food safety and reducing the use of agricultural chemicals are to be achieved. Farmers need more information about food safety risks related to the products they consume themselves, and technical guidance on the safe use of farm chemicals when growing food for market. However, such measures will not be effective unless the external pressures on farmers are also addressed, through consideration of market incentives to use farm chemicals and the impact of consumer demand.  相似文献   
104.
Food security and sustainable agricultural development are the hot issues of scientific research, especially after the population affected by hunger surprisingly increased in 2016. Long-lasting and recurrent famines caused by natural disasters and wars have afflicted Ethiopia. Unlike Ethiopia, which is still struggling to achieve food self-sufficiency, China managed to quickly become food self-sufficient at a rapid speed, despite the fact that it also faced the same challenges of famine over the last century. In the backdrop of differing environmental and socio-political challenges the two countries face, comparing the similarities and differences between the two countries will yield important lessons and insights for Ethiopia to follow to achieve food self-sufficiency. Here, the progress towards food security in Ethiopia and China is presented to quantitatively compare the gap of agricultural production between both countries. We found that food production in Ethiopia is heavily constrained by drought, soil degradation, climate change, out-dated agricultural production technologies, and poverty. According to these challenges, we examined corresponding responses in China to propose solutions for achieving food self-sufficiency in Ethiopia, given the realities of its unique national situation.  相似文献   
105.
This paper offers a systematic analysis of the concepts and contexts that frame the climate-smart agriculture (CSA) discourse in the academic and policy literature. Documents (n?=?113) related to CSA and published in peer-reviewed journals, books, working papers, and scientific reports from 2004 to 2016 were reviewed. Three key trends emerged from the analysis: studies are biased towards global policy agendas; research focuses on scientific and technical issues; and the integration of mitigation, adaptation, and food security (the three pillars of CSA) is becoming a popular scholarly solution. Findings suggest that CSA is a fairly new concept used to describe a range of adaptation and mitigation practices without a specific set of criteria. Although CSA is often framed around the three pillars, the underlying issues constructing the discourse differ at global, developing, and developed country scales. Although there is increasing research on developing countries, particularly in relation to how CSA can transform smallholder agriculture, there is a paucity of research documenting the experiences from developed countries. The findings suggest that research on CSA needs to move beyond solely focussing on scientific approaches and only in certain geographical contexts. If CSA is to be applicable for farmers across the globe, then cross-disciplinary research that is underpinned by broad socio-economic and political contexts is essential to understand how differences in narratives might affect implementation on-the-ground in both developing and developed countries.

POLICY RELEVANCE

Although policy makers are increasingly supportive of the climate-smart agriculture (CSA) approach, the rhetoric has largely been developed on the basis of scientific and technical arguments. The political implications of varying perspectives have resulted in a growing divide between how developing and developed countries frame solutions to the impacts of climate change on agriculture under the 2015 Paris Agreement. Different framings are part of the explanation for why the scope of CSA is being rethought, with the scientific community redirecting attention to seeking a separate work programme under the United Nations Framework Convention on Climate Change (UNFCCC). The current policy framing of CSA will give no new policy direction unless it grounds itself in the smallholder farmer and civil society contexts.  相似文献   
106.
Fast food restaurants and liquor stores—vice stores—have been shown to be more prevalent in predominantly Black and low income U.S. neighborhoods, and are associated with a number of health risks and social ills. The purpose of this study was to investigate in the City of Chicago vice store density and spatial distribution as a function of racial, socioeconomic, and other population characteristics; to examine spatial clustering among these outlets; and to study how store turnover follows population change over a 13-year period. We used spatial point process analysis to fit linear and non-linear models for the intensity function of stores. Spatial clustering was estimated using the K function. We found heterogeneous associations between stores and population characteristics, with the most consistent finding being a positive association between percent Black and liquor store exposure. A high degree of spatial clustering was evident, and liquor stores were more likely to stay in business over time than fast food restaurants. However, when liquor stores closed, they were more likely to be replaced by non-vice businesses. Results suggest that vice stores are associated with lower positions in racial and socioeconomic hierarchies, and this patterning is often durable over time.  相似文献   
107.
Urban agriculture and the sustainability fix in Vancouver and Detroit   总被引:1,自引:1,他引:0  
Both Vancouver, British Columbia, and Detroit, Michigan, have significant and growing urban agriculture movements. In this article, I follow recent work investigating the connection between urban agriculture and neoliberalization to determine how these local governments have used urban agriculture in narratives of economic development to selectively pursue a sustainability fix. I analyze how different regimes of local governance have influenced the urban agriculture movements, leading to local, hybridized fixes that adapt to different material and discursive contexts in each place. I argue that in both cities, urban agriculture has radical potential as a grassroots response to economic and environmental injustice, but has also been enrolled as a device by the local state in which the primary goal of sustainability planning becomes enhanced economic competitiveness. Pursuing an agenda of food justice requires examining the larger context and effects of municipal involvement with food movements.  相似文献   
108.
食物浓度对模糊秀体溞生长和繁殖的影响   总被引:1,自引:1,他引:0  
尹娟  韩博平 《湖泊科学》2008,20(3):344-350
模糊秀体潘是热带水体中枝角类的主要优势种,它在竞争及对热带水体的适应方面的优势尚不清楚。本文以模糊秀体潘为研究对象,观察不同食物浓度下其生长和繁殖的特点,探讨模糊秀体潘成热带水体优势种的原因。以蛋白核小球藻为食物,浓度梯度设为0.05mg/L、0.1mg/L、0.3mg/L、0.6mg/L和1.0mg/L小球藻浓度为0.05mg/L的培养液中,模糊秀体潘存活率很低且未观察到繁殖现象其它4个浓度小球藻喂养的模糊秀体潘体长生长率和最大体长均随食物浓度的升高而增加,最大体长分别达到1.087mm、1.125mm、1.225mm、1.313mm;食物浓度对模糊秀体溢的胚胎发育时间,平均寿命,个体累计产幼数无显著影响:随着食物浓度的升高,模糊秀体滏初次怀卵体长显著增加,繁殖前期的历时相应缩短,平均每胎产幼数增加:内禀增长率随食物浓度升高而增大,达到0.6mg/L后比较稳定。浓度为0.6mg/L时,模糊秀体潘的净生殖率也达到最大值。1.0mg/L组的世代时间最短,内禀增长率接近最大值。0.6mg/L和1.0mg/L为模糊秀体潘生长比较适宜的食物浓度。热带自然水体中,模糊秀体潘相对其它浮游动物个体小和怀卵率低的现象并非食物不足所致;食物充足条件下的最大成体的个体大小与野外样品接近,也说明自然水体中捕食并没有显著影响成体的个体大小。模糊秀体潘体型较小、身体透明、行动敏捷,容易逃避鱼类的捕食,可能是模糊秀体潘能在食物丰富的热带水体中,特别是透明度较低的富营养化湖泊中能够成为枝角类中优势种的主要原因。  相似文献   
109.
Himalayan mountain system is distinguished globally for a rich biodiversity and for its role in regulating the climate of the South Asia.Traditional crop-livestock mixed farming in the Himalaya is highly dependent on forests for fodder and manure prepared from forest leaf litter and livestock excreta. Apart from sustaining farm production, forests provide a variety of other tangible and intangible benefits, which are critical for sustainable livelihood of not only 115 million mountain people, but also many more people living in the adjoining plains. Extension of agricultural landuse coupled with replacement of traditional staple food crops by cash crops and of multipurpose agroforestry trees by fruit trees are widespread changes. Cultivation of Fagopyrum esculentum,Fagopyrum tataricum, Panicum miliaceum, Setaria italica and Pisum arvense has been almost abandoned. Increasing stress on cash crops is driven by a socio-cultural change from subsistence to market economy facilitated by improvement in accessibility and supply of staple food grains at subsidized price by the government. Farmers have gained substantial economic benefits from cash crops. However, loss of agrobiodiversity implies more risks to local livelihood in the events of downfall in market price/demand of cash crops, termination of supply of staple food grains at subsidized price, pest outbreaks in a cash crop dominated homogeneous landscape and abnormal climate years. Indigenous innovations enabling improvement in farm economy by conserving and/enhancing agrobiodiversity do exist, but are highly localized. The changes in agrobiodiversity are such that soil loss and run-off from the croplands have dramatically increased together with increase in local pressure on forests. As farm productivity is maintained with forest-based inputs, continued depletion of forest resources will result in poor economic returns from agriculture to local people,apart from loss of global benefits from Himalayan forests. Interventions including improvement in traditional manure and management of on-farm trees,participatory development of agroforestry in degraded forest lands and policies favoring economic benefits to local people from non-timber forest products could reduce the risks of decline in agricultural biodiversity and associated threats to livelihoods and Himalayan ecosystems.  相似文献   
110.
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