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1.
草原工程侵蚀区植被恢复模式的水土保持效应   总被引:3,自引:0,他引:3  
以内蒙古草原大型露天煤矿开采形成的人工再塑地貌为研究对象,针对水土流失特点,结合自然气候、立地条件等因素,以快速恢复工程侵蚀区受损植被、减少水土流失为目的,通过水土保持措施组合配置试验,研究草原工程侵蚀区人工再塑地貌不同植被恢复模式的水土保持效应。结果表明:人工再塑地貌平台植被恢复采用“栽植灌木+种草”的措施配置灌木保存率为85.4%,草本植物盖度76%,土壤风蚀量比其他样区减少30%~85%;边坡植被恢复采用“栽植灌木+种草”模式和“生物笆+灌木”模式植物盖度达60%以上,抗蚀保土能力较强;通过秩和比法进行综合效益评价,“生态袋+种草”和“栽植灌木+种草”两种模式在治理投资成本与水土保持效益方面结合较好,水土流失防控效果明显,可在草原工程侵蚀区人工再塑地貌边坡水土流失治理中优先应用。  相似文献   
2.
郭磊 《湖南农机》2012,(5):184-185
按照"卓越工程师教育培养计划"围绕工程能力这一核心问题,实践教学在整个教学过程中的重要性日益突出。文章按照卓越工程师培养对实践教学的新要求,结合南昌工程学院热能与动力工程专业的实际,提出了多项实践教学改革的措施,在实施中做了一些有益的探索。  相似文献   
3.
网络工程人才的需求与层次化培养   总被引:1,自引:0,他引:1  
随着计算机网络的发展,网络工程的基础性、全局性作用日益增强。构建安全、可靠、高效的网络已成为我国在新的历史条件下的必然选择,网络工程专业人才也成为信息社会的急需人才。本文论述了网络工程的现状与人才需求,并详细论述了培养网络工程人才的策略和层次问题,对培养合格的网络工程人才具有一定的指导意义。  相似文献   
4.
在监理工作中配备既懂工程技术又懂经济、管理和法律知识,具有实践经验和良好职业道德素质的复合型人才一造价工程师,是非常必要的.  相似文献   
5.
本文叙述了高等级公路建设过程中测量监理工程师的职责、作用、应具备的素质,说明了测量监理的工作流程,具有参考价值。  相似文献   
6.
侯进慧 《安徽农业科学》2014,(13):4074-4077
立足应用型高校人才培养实际,以徐州工程学院国家级“卓越计划”实施专业食品科学与工程专业微生物学教学改革实践为基础,讨论了开展面向“卓越工程师”培养的微生物学教学改革措施,以为相关课程的改革提供参考.  相似文献   
7.
Failure to consider both the consumptive and non-consumptive effects of predators on prey can lead to erroneous conclusions about the net effect of the relationship. The predatory devil crayfish, Cambarus diogenes Girard functions as an ecosystem engineer constructing extensive burrow systems through aquatic habitats. Despite crayfish posing a serious predation threat, preliminary data indicate that the federally endangered Hines Emerald dragonfly larvae, Somatochlora hineana Williamson regularly inhabit crayfish burrows. During late summer, S. hineana larval habitat dries up; leaving crayfish burrows as some of the only wetted habitats. Thus, C. diogenes can affect S. hineana through both direct, negative and indirect positive effects. We examined the positive role of crayfish burrows as drought refuges, and the threat of predation by C. diogenes on S. hineana larvae. Monthly field sampling indicated that S. hineana use open channel areas in spring and early summer moving into burrow systems in mid summer when channel areas normally dry. Laboratory experiments and field observations confirmed that crayfish prey on S. hineana larvae. Adult crayfish were a larger predation threat than juvenile crayfish. Despite their negative predatory impact, removal of crayfish from burrows in the field did not enhance densities of S. hineana larvae. Although S. hineana may face the threat of predation in burrows, they face a greater risk of desiccation if they remain in the open channel. These results lead to the counterintuitive conclusion that the maintenance of a predator is important for conserving an endangered prey species.  相似文献   
8.
基于卓越计划的食品工程创新人才培养模式构建与实践   总被引:1,自引:0,他引:1  
以培养食品工程卓越工程师为指引,分析了食品产业发展前景及对应用型创新人才的需求,提出了以产业为导向的食品工程创新人才培养模式,构建了产业导向型"3+1"学历运行模式与教学运行机制。旨在专业贴近产业,教学贴近企业,按通用标准与产业标准培养人才。  相似文献   
9.
African elephants can affect the quality of the habitat of other species by breaking or uprooting trees and shrubs in savannas. Their effect on vegetation has been widely studied but less is known about the effects of such vegetation changes on other animals. We studied how changes in the vegetation caused by elephants influence the selection of microhabitats by five African herbivore species (giraffe, kudu, steenbok, impala, and zebra) in Hwange National Park, Zimbabwe. There was no clear significant effect of overall elephant-induced vegetation changes on microhabitat selection except for the small species (steenbok and impala) that used vegetation modified by elephants preferentially. This is consistent with a medium-term browsing facilitation hypothesis. More subtle possible effects were detected for larger browsers (giraffe and kudu). They selected areas with broken and uprooted plants and avoided coppiced areas. All of the browsers selected sites characterized by plants uprooted and broken by elephants, which were associated with a higher visibility, and ultimately a better probability of detecting an approaching predator, suggesting that perceived predation risk plays an important role in microhabitat selection. These results illustrate how elephants can initiate indirect effects that influence microhabitat selection by other herbivores. Understanding the indirect effects of elephants through changes in food availability and predation risk thus needs further investigation. The results of this study do not provide support for the hypothesis that elephant-induced changes in the structure of habitats have caused the declines in the populations of the other herbivores in the study area.  相似文献   
10.
Populations of organisms that create habitat can often be fragmented throughout landscapes by anthropogenic disturbances such as harvesting and loss or change to the identity of such bioengineers may lead to large changes in biodiversity. Using the fauna associated with a bioengineer, the intertidal mussel Perna perna, we tested hypotheses about the relative importance of larval export from protected populations in marine reserves. Harvesting led to the replacement of P. perna and the domination of shores outside reserves by turf-forming coralline algae, mostly Corallina spp. We determined whether the diverse fauna recruiting onto artificial units of habitat placed within mussel beds differed between reserves and non-reserve areas or whether shores outside reserves, and open to harvesting, received recruits through larval export from reserves. Furthermore, we determined whether this was affected by the distance away from reserves and whether colonisation was achieved by movement of adults from surrounding biogenic habitats or via the plankton. Overall, we found no effect of increasing distance away from a reserve on the cover of adult mussels or associated fauna. We found strong effects of the presence of marine reserves on abundances of molluscs and polychaetes but not crustaceans. There were greater densities of molluscs in sites with a reserve (i.e. inside reserves, and up to 5 km outside reserve boundaries), but more polychaetes in exploited sites. For molluscs, this pattern was driven by gastropods rather than bivalves. Furthermore, although reserves had greater cover of adult mussels than non-reserve areas, recruitment of mussels was not greater inside or near to reserves. Our study illustrates the effectiveness of these reserves in protecting stocks of adult mussels, and although there was no evidence that reserves provided export of the larvae of mussels (the target species), they did provide larval export of non-targeted associated species. By protecting a harvested bioengineer and through export of the larvae of its associated fauna, these reserves fulfil some, but not all the conservation aims of a marine protected area.  相似文献   
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