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51.
If restoration is to become effective, able to compete for limited funds and truly adaptive, it must become evidence‐based. Three of the conditions essential for the establishment and advancement of evidence‐based restoration are (1) collection of baseline information; (2) setting clearly defined goals; and (3) relevant and adequate monitoring. Using a literature review, complemented with an online survey, we reviewed 10 restoration programs in South Africa to assess whether current restoration practice meets these conditions. The review showed good collection of baseline information and the setting of restoration goals that span ecological and socioeconomic considerations. However, to a large extent goals were poorly defined, there was more monitoring of inputs than outcomes, and monitoring of ecological indicators was inconsistent. These shortcomings can undermine restoration impacts, as well as the future sustainability of these expensive programs. We conclude with recommendations on how to mainstream the requirements of evidence‐based restoration into current and proposed restoration programs.  相似文献   
52.
A global strategy is necessary to achieve the level of coordination, synergy and therefore optimization of resources to achieve the broad goal of conserving mammals worldwide. Key elements for the development of such a strategy include: an institutional subject that owns the strategy; broad conservation goals, quantitative targets derived from them and appropriate indicators; data on the distribution of species, their threats, the cost-effectiveness of conservation actions; and a set of methods for the identification of conservation priorities. Previous global mammal research investigated phylogeny, extinction risk, and the species and areas that should be regarded as global conservation priorities. This theme issue presents new key elements: an updated Red List Index, a new list of evolutionarily distinct and globally endangered species, new high-resolution mammal distribution models, a global connectivity analysis and scenarios of future mammal distribution based on climate and land-cover change. Area prioritization schemes account for mammalian phylogeny, governance and cost-benefit of measures to abate habitat loss. Three discussion papers lay the foundations for the development of a global unifying mammal conservation strategy, which should not be further deterred by the knowledge gaps still existing.  相似文献   
53.
Engaging citizens is vital to achieving people‐centred health research. This paper aims to put attention to dynamics of power and dynamics of difference back at the centre of citizen engagement in health research priority‐setting. Without attention to power and difference, engagement can lead to presence without voice and voice without influence, particularly for disadvantaged and marginalised groups. By analysing six key bodies of literature, the paper first identifies the different components of engagement—who initiates, for what purpose, who participates, and how they participate—and the dynamics of power and dynamics of difference relevant to them. For each component of engagement, the ethical considerations relating to those dimensions of power and dimensions of difference are characterised for the research priority‐setting context and preliminary guidance on how they might be addressed is provided. An initial framework comprised of a series of questions reflecting these ethical considerations has been developed for use by researchers and citizens when designing engagement processes for research projects. Where researchers and citizens attend to the framework's questions and then revise their priority‐setting processes’ design to better represent diversity and mitigate power disparities, more inclusive citizen engagement is promoted. Disadvantaged and marginalised groups are more likely to be present and heard, which, in turn, will help generate research projects with topics and questions that encompass and more accurately reflect their health needs.  相似文献   
54.
This paper reviews a variety of studies designed to examine the effects of extinction upon control by specific stimulus-outcome (S-O) associations in Pavlovian conditioning. Studies conducted with rats in a magazine approach conditioning paradigm have shown that control by specific S-O associations is normally unaffected by extinction treatments, although other aspects of conditioned responding seem affected in a more enduring way. However, recent work suggests that extinction can undermine control by such associations if it is administered after the conditioned stimulus is weakly encoded. The results from these studies suggest that it may be important to consider multiple response systems in assessing the impact of extinction. Studies conducted with the flavor preference learning paradigm in rats also show that specific S-O associations can be undermined by procedures that involve presenting a flavor cue in the absence of its associated nutrient. These findings provide no support for the view that flavor preference learning necessarily entails some unique learning process that differs from more conventional processes. As in other situations, some of these effects likely involve a masking process, but the extent to which masking or true associative weakening occurs in extinction more generally is a topic that is not well understood. Finally, we present some data to suggest that extinction also involves conditional "occasion-setting" control by contextual cues. Special procedures are recommended in assessing such learning when the goal is to distinguish this form of learning from other more conventional mechanisms of extinction.  相似文献   
55.
中国土壤动物多样性监测: 探知土壤中的奥秘   总被引:1,自引:0,他引:1  
土壤动物多样性变化及其对环境的指示作用已被学术界和政府决策部门高度关注。本文从土壤动物多样性监测的重要性及面临的挑战、国内外土壤动物多样性监测概况等方面进行了评述, 提出了未来、尤其是2016-2020年我国土壤动物多样性监测的目标、站点布局、样地设置、监测类群和指标等, 并讨论了在制定土壤动物多样性监测方案时需考虑的问题, 有助于在全国开展多点化土壤动物多样性及分布状况的监测工作, 建立标准统一、数据共享的土壤动物监测网, 提供完整的、可信的监测数据, 为国家生态文明建设提供科技支撑。  相似文献   
56.
植物生长调节剂对火龙果坐果率和果实生长的影响   总被引:1,自引:0,他引:1  
以‘红龙果Ⅱ’为试材,研究不同生长调节剂处理对火龙果坐果率和果实生长的影响。结果表明:浓度为30 mg/L GA3或100 mg/L 6-BA对提高火龙果坐果率及促进果实生长效果最佳。  相似文献   
57.
叠层石的形态和它们与陆源沉积的关系反映了沉积盆地的构造背景。在巴西中部地区 ,叠层石出现在中元古和新元古代的 Paranoa′群、Vazante群和 Bambui′群。根据沉积学和矿物学的研究分析 ,Paranoa′群形成于被动边缘盆地 ,而另外两个群形成于前陆盆地。Vazante群沉积在形成巴西褶皱带的山脉附近 ,然而 Bam bui′群的大部分都形成于克拉通地区。通常远离山脉褶皱带的 Paranoa′群和 Bambui′群内的叠层石建造的形态和规模的改变与环境的变化有关。在柱状生长方向的频繁变化和不规则的丰富陆源物质的夹层进入叠层石 ,表征活跃的构造背景 ,例如在Vazante,Paranoa′群和 Bam bui′群的西部  相似文献   
58.
The study aims to investigate the effect of foliar spray with three plant growth regulators (PGRs) p-Chlorophenoxyacetic acid (CPA) at 20 and 40 ppm; Gibberellic acid (GA3) at 20 and 30 ppm, 1-Naphthaleneacetic acid (NAA) at 10 and 20 ppm on the response of fruit set, yield, and fruit quality of some hot pepper cultivars (Chillina, Parbirian, Shampion, and Hyffa) grown in sandy soil under plastic tunnels as compared to the control. Spraying Chillina cultivar GA3 at 30 ppm significantly increased the number of fruits/ plant and fruit set (%), yield/plant, and total yield/fad. In addition, the contents of TSS and Vit C, furthermore, maximum capsaicin content were observed in chili fruits in both seasons. However, the interaction between Chillina cultivar and spraying with GA3 at 20 ppm ranked second in yield and quality. The interaction between Parbirian cultivars and spraying with GA3 at 20 or 30 ppm increased the number of flowers/plants in both seasons. On the other hand, the interaction between Shampion cultivar and spraying with tap water (control) gave the lowest values of the number of flowers/ plants, the number of fruits/ plant and fruit set (%), yield, and its components, and fruit quality in both seasons.  相似文献   
59.
在人工气候室研究了15个光敏核雄性不育系粳稻抽穗与结实对日长与温度的反应特性。1个品系抽穗的光周期反应极弱,8个中等;6个强;农垦58S与其原种反应均强.但PSP略有差异;而且农垦58S在雌雄蕊原基分化前移入LD,不但抽穗延迟且结实率显著降低,而农垦58抽穗虽延迟但结实正常。高温抽穗促进车品系间差异大,从0~4d.9%,较多为22%~38%。15个不育结实的光周期反应明显;它们在高温、低温、LD下结实明显受阻,有的即使在SD下结实率亦很低。说明它们雄性细胞较孱弱易受不良光、温条件危害,可能是遗传上有缺陷;繁种时应注意地区的光、温条件,并利用SD下结实尚可的品系。  相似文献   
60.
KCl处理对百合柱头生理及结实的影响   总被引:3,自引:0,他引:3  
以百合(Lilium)品种‘Pollyanna’为材料,研究了KCl处理对柱头中SOD、POD及CAT等3种保护酶活性、可溶性蛋白含量以及电阻率的影响。结果表明,处理后3种酶的活性均表现出不同程度的应激性升高,其中SOD活性在花开当天和花开1d显著升高,在蕾期与花开2d极显著升高;花开当天及花开1d的POD活性极显著升高;CAT活性在花开1d升高显著,花开2d及3d时升高极显著。柱头可溶性蛋白含量及电阻率无显著变化,表明KCl处理削弱了细胞膜的膜脂过氧化作用,延缓了柱头衰老,提高了授粉受精作用,且与结实率升高表现出一定相关性。  相似文献   
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