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951.
澜沧江自然保护区云南铁杉群落特征研究 总被引:1,自引:0,他引:1
采用样方调查的方法,对澜沧江自然保护区云南铁杉林进行群落特征研究,结果表明:群落内共有维管植物48科70属99种及变种,蕨类植物5科6属8种,种子植物43科64属91种;壳斗科、兰科、山茶科、菊科和杜鹃花科为群落主要组成科;群落垂直结构明显,可分为乔木层、灌木层、草本层和层间植物;群落以中小高位芽植物(42.42%)占优势,叶级以中型叶为主(30.30%),叶片特征以单叶(81.82%)、革质叶(53.54%)、全缘叶(64.65%)、渐尖叶(41.41%)为主;对群落内云南铁杉树高、胸径和株数百分比进行分析,发现群落具有一定的波动性. 相似文献
952.
向海自然保护区鹤类生境优化的水量调控 总被引:4,自引:0,他引:4
在基于向海自然保护区湿地水位达到165m,鹤类可选择生境面积最大这一研究结果的基础上,利用区域水量平衡原理,计算了为维持这块鹤类生境面积的健康存在,需要从对向海自然保护区起重要水源调控功能的向海水库调出的水量,并根据研究区的实际条件,提出了研究区湿地生境安全的用水保障措施。 相似文献
953.
Establishment of protected areas in different ecoregions, ecosystems, and diversity hotspots under successive political systems 总被引:1,自引:0,他引:1
Eva-Liis Tuvi Ain Vellak Ülle Reier Robert Szava-Kovats Meelis Pärtel 《Biological conservation》2011,(5):1726-1732
Protected areas are valuable tools for nature conservation but the effectiveness of reserve networks must be monitored continuously. Knowing the history of the establishment of protected areas can help to improve future conservation. We explore how different ecoregions, ecosystems and diversity hotspots have been incorporated in protected areas in Estonia during the last century. We found that the average rate of establishment of protected areas has been surprisingly constant despite profound changes in political systems. However, establishment of protected areas has varied regionally; an agricultural region in south-east Estonia has seen less protection, partly due to lower biodiversity. Wetland ecosystems were initially more placed under protection, whereas recently semi-natural grasslands have gained more attention. In contrast, farmland is under-protected. Surprisingly, biodiversity hotspots were no more protected than the national average. We consider how the development of a protected area network has been influenced by individual persons and public opinion under successive political systems. We suggest that simultaneous gap analysis of ecoregions, ecosystems and diversity hotspots provides a more complete picture than examining a single aspect. Therefore this study can be used as a model for other regions. 相似文献
954.
湖北木林子自然保护区常绿落叶阔叶混交林干扰特征 总被引:1,自引:0,他引:1
常绿落叶阔叶混交林是木林子自然保护区的1种主要植被类型。在各种自然干扰和人为干扰的协同作用下,形成了木林子常绿落叶阔叶混交林特有的干扰体系。在常绿落叶阔叶混交林的保护和经营中,要利用封山育林、森林抚育、合理择伐和人工促进天然更新等增益性人工干扰,坚决阻止过渡的森林采伐和毁林开荒等破坏性人工干扰。应参照以自然林窗干扰,采用择伐方式经营常绿落叶阔叶混交林。 相似文献
955.
为了解白马雪山国家级自然保护区内野生动物及其生存状况,布设了长为3000m的固定监测样线17条,并结合随机样线,定期、不定期地采用肉眼观察、望远镜观察或拍照后识别的方法监测动物种类、密度、分布、种群变化等情况.对2006~2009监测数据进行分析,保护区内有国家重点保护动物15种,其中出现频率较高的有滇金丝猴、岩羊、苏门羚、斑羚等.野生动物受威胁因子主要有人为活动、自然灾害.监测结果表明,保护区内滇金丝猴等国家重点保护动物的数量总体上呈上升趋势. 相似文献
956.
957.
958.
通过对浙江古田山自然保护区4个主要阔叶树种——甜槠、木荷、青冈和石栎的调查采样,测定了4个物种共1160张叶片的叶长、叶宽和叶面积,基于此构建4个物种叶面积与叶长和(或)叶宽的8种常用回归模型。结果表明,模型SA=a(LW)+b具有最高的决定系数(R~2=0.97-0.99)和最低的均方差(MSE=0.52-1.59);幂指数模型SA=aW~b是所有单变量模型中拟合效果最佳的模型。 相似文献
959.
在较全面野外调查的基础上,结合历史资料,对将石自然保护区壳斗科植物资源及发掘利用状况进行了初步研究。调查结果表明,该区共有壳斗科植物6属26种1变种,其中多数物种在园林应用、造林、淀粉植物、木材利用等方面具有较高的开发价值。最后对该区的壳斗科植物资源的开发与利用提出了建议。 相似文献
960.
Paul R. Armsworth Lisette Cantú-Salazar Mark Parnell Zoe G. Davies Rob Stoneman 《Biological conservation》2011,(1):423-429
Protected area management must be resourced adequately to achieve its conservation objectives. The variability in management costs across candidate sites for protection therefore should inform conservation planning. For example, when considering whether to accept a donation of a property, a conservation organisation must determine whether an adequate endowment is available to fund future management activities. We examine variation in management costs across 78 small protected areas in the UK that are managed by a conservation NGO, the Yorkshire Wildlife Trust. Management costs exceed acquisition costs when funded on an endowment basis and are not correlated with acquisition costs or with proxy measures for conservation costs commonly relied upon in conservation planning studies. A combination of geographic, ecological and socioeconomic characteristics of sites explains 50% of the variation in management costs. Site area is the most important determinant of management costs, which demonstrate economies of scale; implementing conservation management on an additional hectare adjacent to a larger protected area would incur a lower cost than doing the same adjacent to a smaller site. In evidencing this effect of site area, we avoid problems of spurious correlation that confound previous studies. Protected areas that encompass a greater richness of priority habitats for conservation also require more expensive management. Conservation organisations may have little option but to create small protected areas to conserve biodiversity in highly fragmented landscapes, but the decision to do so should take account of the greater cost burden that small protected areas incur. 相似文献