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91.
The Diagnostic Recommendation and Integrated System (DRIS) was employed to interpret nutrient analyses of leaf tissues from ber fruit tree orchards grown in semi-arid and arid areas of Punjab in northwest India. The DRIS norms were established for various nutrient ratios obtained from the high-yield population and were used to compute DRIS indices, which assessed nutrient balance and their orders of limitation to yield. Nutrient sufficiency ranges derived from DRIS norms were 0.688–1.648%, 0.184–0.339%, 1.178–1.855%, 1.064–1.768%, 0.234–0.391%, and 0.124–0.180% for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) and were 55–205, 26–80, 17–33, and 5–11 mg kg?1 for iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu), respectively. According to these DRIS-derived sufficiency ranges, 79%, 76%, 76%, 75%, 84%, and 72% of samples were sufficient, whereas 13%, 15%, 21%, 14%, 7%, and 18% of total samples were low in N, P, K, Ca, Mg, and S, respectively. For micronutrients, 84%, 85%, 77%, and 86% of samples were sufficient, whereas 6%, 3%, 8%, and 2% of samples were low in Fe, Mn, Zn, and Cu, respectively.  相似文献   
92.
近几年,"美丽乡村"建设始终是社会上的热门话题。各地出现的"美丽乡村"也成为当地最热门的旅游地区。文章围绕"美丽乡村"建设展开,分析了当下"美丽乡村"建设过程中存在的一些问题,提出了大学生回乡对解决这些问题所产生的积极作用,探讨了鼓励大学生回乡的方法,对"美丽乡村"的建设具有一定指导意义。  相似文献   
93.
Diagnostic and recommendation integrated system (DRIS) norms were established for various nutrient ratios obtained from the high-yield population of maize cultivated in submountainous areas of Punjab and were used to compute DRIS indices. Nutrient sufficiency ranges derived from DRIS norms were 1.67–3.12, 0.23–0.43, 0.89–2.56, 0.21–0.50, 0.1–0.32, and 0.10–0.20% for nitrogen (N), phosphorous (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) and were 181–278, 27–75, 14–29, and 4–8 mg kg?1 for iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu), respectively. According to these DRIS-derived sufficiency ranges, 95, 94, 95, 87, 90, and 86% of samples were sufficient whereas 4, 3, 4, 2, 2, and 2% of samples were low in N, P, K, Ca, Mg, and S, respectively. In micronutrients, 80, 90, 85, and 68% of samples were sufficient, whereas 36 17, 10, 14, and 31% samples had excessive Fe, Mn, Zn, and Cu, respectively. Thus, the DRIS approach can be employed to obtain the fertility status of the soil, and the amount of each nutrient can be computed for balanced utilization of fertilizers.  相似文献   
94.
This study assessed the soil organic C (SOC) and soil nutrients in smallholding home garden, woodlot, grazing land, and cropland at two soil depths and two sites in Wolaita Zone, southern Ethiopia. The results showed that soil properties were significantly influenced by land use. The home garden had significantly higher (p < 0.05) SOC and soil nutrients when compared to the cropland. When the home garden was compared to the woodlot and grazing land uses, it had significantly higher (p < 0.05) values except in SOC, total N (TN), cation exchange capacity (CEC), and exchangeable Ca. Cropland, in comparison with grazing land and woodlot, had a non‐significant difference except TN. The SOC stock (0–40 cm) in the home garden, woodlot, grazing land and cropland was 79.5, 68.0, 65.0, and 58.1 Mg ha?1, respectively. Home garden significantly differed (p ≤ 0.05) in SOC only from cropland, and this was attributed not only to the relatively higher organic input in the home garden but also to the little organic matter input and frequently tillage of the cropland. The similar SOC among the home garden, woodlot and grazing lands may imply that the balance between inputs and outputs could be nearly similar for the land uses. Soil TN and CEC had a nearly similar pattern of difference as in SOC among the land uses because of their close relationship with SOC. In general, the land use influence on soil nutrients can be in the order: home garden > wood land ≈ grazing land ≈ cropland, with home garden showing the least difference from the woodlot and the greatest from the cropland. In the agroecosystem, in general, the influence of smallholding home garden on SOC and soil nutrient was marginally different from Eucalyptus woodlot and grazing lands but evidently different from cropland.  相似文献   
95.
Southeast Asia is one of the richest reservoirs of biodiversity on earth and home to one of the highest concentrations of endemic species. Many protected areas (PA) have been established across the region, but to date no systematic evaluation of their efficacy has been published because no comprehensive dataset was available which could be fed into an analysis of conservation gaps. We collected the geographic range for 1086 mammal species of Southeast Asia and we built species-specific habitat suitability models for 901 of them. We performed two gap analyses (one based on a combination of distribution models and distribution ranges and one based on distribution ranges only) for each mammalian species, to evaluate the effectiveness of the existing network of PA and to identify priority regions and priority species for expanding and consolidating the network. Our results indicate that 7.5-8.2% of species are not covered by any PA, and 51.6-59.1% are covered only partially. These species are distributed throughout the entire study area and their conservation requires the creation of new PA that can help fill this existing conservation gap. This would be particularly important for species which are endemic of small islands, where species survival is often threatened by the presence of introduced species and habitat conversion. Yet PAs cannot be considered as the ending point of a conservation strategy, because overall, 34% of the species we analyzed (many of which already covered by existing PAs) were at risk of extinction when considering the IUCN red-list criteria. PAs should therefore be considered in a broader framework of all local ecological and socio-economic trends, including the growing human population, growing economy and infrastructure development.  相似文献   
96.
阐述了云南省大理白族自治州喜洲镇白族农户生态庭园的6种模式类型,即普通型、集约养殖型、劳务输出型、庭园车间型、水面开发型和服务经营型,并在研究模式结构基础上简析了庭园经营与大田生产的关系和白族庭园的特殊性,提出了进一步建设农户生态庭园的若干建议。  相似文献   
97.
在描述家庭网络的重要性的基础上对基于家庭网络的数字融合及其影响进行分析和研究。随着信息技术和产品逐步由多标准向标准融合过渡,网络、通信、软件、硬件和消费电子产品等生产厂家通过成立联盟,推动家庭网络技术和产品相互兼容。于是产业融合得到促进,家庭网络市场逐步扩大。家庭网络推动服务融合和创新,促进形成新的价值链。在新的价值链中,新的商业模式促进网络运营、应用和服务的改变和融合,合作和协同不可或缺,并得到了政策和资源方面的支持。对于家庭网络业的发展来说,技术是基础,内容是源泉,应用是动力,协同是关键。  相似文献   
98.
Experimental forests and ranges are living laboratories that provide opportunities for conducting scientific research and transferring research results to partners and stakeholders. They are invaluable for their long-term data and capacity to foster collaborative, interdisciplinary research. The San Joaquin Experimental Range (SJER) was established to develop appropriate land management practices on foothill rangelands in California. SJER has a long and rich history of avian research. Natural history observations recorded since 1935 demonstrate that oak woodlands are one of the most diverse habitat types in North America. Early avian studies focused on California quail (Callipepla californica) as a game species and led to insights on quail diet and habitat requirements. Starting in the late 1970s, the focus of avian research shifted to methods for detecting changes in wildlife populations over time and response to management practices. This research has led to important recommendations for implementing bird monitoring programs. Using data collected on bird numbers, in conjunction with monitoring reproductive success of all species, recent studies have examined life history strategies, source-sink dynamics, the effects of livestock grazing, and the impacts of an invasive species on native cavity-nesting species. We are currently in the process of examining population trends and predicting the effects of climate change using long-term data. SJER continues to provide unique opportunities for research and educational activities that increase our understanding of the foothill oak woodlands of California.  相似文献   
99.
为提升家居生活的安全性、便利性、舒适性、艺术性及实现环保节能,需实时监测家居环境的温湿度、亮度等条件,以便更好地了解家居环境并进而对家居环境进行智能控制。鉴于此,基于高性能、低功耗单片机MSP430F149通过单总线方式控制温湿度传感器AM2301,实现了智能温湿度计对家居环境中温度、湿度进行监测。当家居环境中的温湿度过高、过低时都会有相应的LED灯闪烁警告;并且通过LabVIEW设计实现了上位机软件显示温湿度数据,方便通过PC机实时查看家居环境中的温湿度值。为智能家居的环境监测做了基础工作,并方便基于MSP430F149单片机做进一步扩展工作,为实现智能家居奠定了基础。  相似文献   
100.
随着经济一体化的推进,人民币在周边国家和地区逐步区域化、国际化已成为不争的事实。本文以云南省参与GMS合作边境贸易结算本币化现象为切入点,阐述了边境贸易结算本币化的现状、分析了正负面效应,提出促进云南省与周边GMS国家边境贸易本币结算和人民币区域化的对策建议。  相似文献   
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