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871.
哀牢山湿性常绿阔叶林和次生林木质物残体的组成与碳贮量 总被引:7,自引:0,他引:7
研究了哀牢山山地湿性常绿阔叶林和3个主要次生演替类型(栎类萌生林、滇山杨林和旱冬瓜林)木质物残体的组成和碳贮量特征.结果表明:哀牢山徐家坝地区原生森林(常绿阔叶林)木质物残体的碳贮量达36.56t.hm-2,树种组成以腾冲栲、木果石栎和景东石栎等为主,多数是直径≥10cm的大径级、处于中等分解状态的倒木.这主要是由于该区常年潮湿温凉,木质物残体中占优势的壳斗科倒木的材质坚硬,难以分解.3类次生林木质物残体的碳贮量在1.2~5.0t.hm-2,为栎类萌生林>滇山杨林>旱冬瓜林,表现出木质物残体碳贮量随群落演替进程而逐渐增加的趋势. 相似文献
872.
小兴安岭南坡野猪家域分析 总被引:13,自引:1,他引:12
采用笼式活捕野猪,利用无线电遥测技术、R2V、Arcview 和SPSS 软件技术,于2004 年7 月15 日至2006年1 月19 日,对小兴安岭南坡野猪家域进行测定、计算和分析,以了解该地区野猪的家域变化规律。研究结果表明:季节变化影响野猪家域面积,在春、秋季,野猪的家域面积显著大于冬季,而春、夏季间无显著差异;不同性别及年龄野猪家域大小也不同,成体雄性秋季发情期和亚成体春季分窝期家域面积显著增加;在冬、春季家族群野猪的家域面积显著大于独体野猪家域面积,说明家族群对家域面积有影响;亚成体家域大小主要受家族群家域的影响,家族群野猪面积大,相应地家族野猪中亚成体家域面积也大。 相似文献
873.
Shen Xian-sheng 《植物学报(英文版)》1986,28(6)
It is now known that there are 1108 species (including varieties) of vascular plants, in the Tiantangzhai Mountainous region, which belong to 565 genera and 152 families. The Dabieshan Mountains first took shape in the Sinian Period. The origin of the flora of the Dabie Mountains is very ancient, and the flora originated principally from the Tertiary ancient tropical flora. There are many ancient families and genera as well as many relic species. There are all told 81 monotypic and oligotypic genera which are genetically ancient or primitive in the Tiantangzhai Mountainous Region The flora of the Dabieshan Mountains comprises a portion of the flora of East China. In this paper, author has drawn a clear line of demarcation between East China and Central China, from Yichang to Xiangfan in Hubei Province; and a dividing line between East China and North China, through the Tongbaishan Mountains from the Southern foot of the Funiushan Mountains to Huai river. 相似文献
874.
《岭南科学杂志》(Lingnan Science Journal)为原岭南大学创办的英文刊物,是我国现代最早、最为著名的以刊登生物科学及农业科学成果为主的期刊之一。其所刊登的昆虫分类与区系研究成果极大地推动了当时我国昆虫学事业的发展,也成为我国昆虫多样性研究,特别是华南地区昆虫多样性研究不可或缺的基础资料。本文通过查阅中山大学生物博物馆资料室中该期刊珍贵的原始文献资料,对其自创刊至停刊30年间所发表的全部昆虫分类与区系研究论文进行调查与统计,分析了相关工作所涉及的昆虫类群、作者、新属种发表情况以及物种区系分布等信息,同时提供了全部论文的题名索引。结果表明:该杂志所刊登的昆虫分类与区系研究论文对于我国昆虫学研究意义重大,不但大量增加了新分类单元的数量,同时加深和细化了我们对物种区系分布的认识,其中广东省及其周边地区为新物种发表最重要的模式产地。这些工作为我国生物多样性热点地区之一的岭南地区昆虫物种多样性本底调查、农林害虫防控以及资源昆虫利用等工作奠定了坚实基础,同时也为粤港澳大湾区生态文明建设提供重要的基础数据。 相似文献
875.
Fei Yu Guangjie Li Shanshan Wei Xianfeng Yi Jianmin Ma Keming Ma Guangwen Chen 《Ecology and evolution》2022,12(1)
In general, it is accepted that gap formation significantly affects the placement of scatter‐hoarded seeds by small rodents, but the effects of different forest gap sizes on the seed‐eating and scatter‐hoarding behaviors of small rodents remain unclear. Thus, we examined the effects of a closed‐canopy forest, forest edge, and gaps with different sizes on the spatial dispersal of Quercus variabilis acorns and cache placement by small rodents using coded plastic tags in the Taihang Mountains, China. The seeds were removed rapidly, and there were significant differences in the seed‐eating and caching strategies between the stand types. We found that Q. variabilis acorns were usually eaten after being removed from the closed‐canopy forest and forest edges. By contrast, the Q. variabilis acorns in the forest gap stands were more likely to be scatter‐hoarded. The dispersal distances of Q. variabilis acorns were significantly longer in the forest gap plots compared with the closed canopy and forest edge plots. However, the proportion of scatter‐hoarded seeds did not increase significantly as the gap size increased. In small‐scale oak reforestation projects or research, creating small gaps to promote rodent‐mediated seed dispersal may effectively accelerate forest recovery and successional processes. 相似文献
876.
Tianlong Cai Qing Quan Gang Song Yongjie Wu Zhixin Wen Chunlan Zhang Yanhua Qu Gexia Qiao Fumin Lei 《动物学报(英文版)》2021,67(4):431-440
Strong correlations between species diversity and climate have been widely observed, but the mechanism underlying this relationship is unclear. Here, we explored the causes of the richness–climate relationships among passerine birds in China by integrating tropical conservatism and diversification rate hypotheses using path models. We found that assemblages with higher species richness southwest of the Salween–Mekong–Pearl River Divide are phylogenetically overdispersed and have shorter mean root distances (MRDs), while species-rich regions northeast of this divide (e.g., north Hengduan Mountains–south Qinling Mountains) are phylogenetically clustered and have longer MRDs. The results of the path analyses showed that the direct effect of climatic factors on species richness was stronger than their indirect effects on species richness via phylogenetic relatedness, indicating that neither tropical conservatism nor diversification rate hypotheses can well explain the richness–climate relationship among passerines in China. However, when path analyses were conducted within subregions separately, we found that the tropical conservatism hypothesis was well supported in the southwestern Salween–Mekong–Pearl River Divide, while the diversification rate hypothesis could explain the richness–climate relationship well in the northeastern divide. We conclude that the diversity patterns of passerines in different subregions of the Eastern Himalayas-Mountains of Southwest China may be shaped by different evolutionary processes related to geological and climatic histories, which explains why the tropical conservatism or diversification rate hypothesis alone cannot fully explain the richness–climate relationships. 相似文献
877.
记述采自陕西省秦岭山区斑胸蚜蝇属1新种及1新记录种,即楯斑斑胸蚜蝇Spilomyiascutimaculata,sp.nov.和连斑斑胸蚜蝇SpilomyiapanfiloviZimina1952。模式标本保存于陕西理工学院陕西省资源生物重点实验室。 相似文献
878.
879.
The influence of herbivory on plant cover and species composition in the Pryor Mountain Wild Horse Range,USA 总被引:4,自引:0,他引:4
We investigated the effects of short- and long-term ungulate grazing on plant species cover and composition in arid lowland and more mesic upland communities of the Pryor Mountain Wild Horse Range (PMWHR). Measurements were taken over two years which differed significantly in growing season precipitation. Interannual differences in plant cover were significantly greater than differences between grazed and ungrazed communities. In the arid lowlands total plant cover decreased from 47% in 1993, a relatively wet year, to 29% in 1994, a relatively dry year. In the more mesic uplands total plant cover decreased from 107% in 1993 to 56% in 1994. The magnitude of change in cover was greatest in the grasses, especially for Pseudoroegneria spicata, the most abundant species in the lowland communities, which decreased from 21% cover in 1993 to 11% in 1994. There was not a consistent effect of herbivory on plant cover across sites, but its effects, particularly on the dominant perennial grasses, were conspicuous at some sites. For instance, in the lowlands cover of P. spicata was 3–12% in long-term grazed sites and 9–28% in short- to long-term ungrazed sites. Our study indicates that abiotic factors (e.g., precipitation) are more likely than grazing to affect abundances of key plant species, and hence ecosystem dynamics, in the PMWHR, and that the effects of herbivory are more localized and more prevalent in the lowland grasses than in the other plant functional groups. 相似文献
880.
山西五台山种子植物区系分析 总被引:16,自引:3,他引:13
五台山有种子植物865种,隶属于392属92科,其中裸子植物3科, 6属, 7种,被子植物89科, 386属, 858种(双子叶植物76科, 294属, 699种,单子叶植物13科, 92属, 159种)。五台山种子植物属的区系成分类型多样,具有明显的温带色彩。突出特征是温带成分占绝对优势,达255属,占总属数的73.48%(其中北温带成分156属,占总属数的为44.96%),在植物区系的组成中具有重要作用。在五台山种子植物种的区系成分中,中国特有种占绝对优势,达286种,占总种数的33.41%,它们是构成五台山优势植被类型的建群种和优势种的主要成分,如华北落叶松、油松、青木千、黄刺玫、虎榛子、蚂蚱腿子等。类平均聚类结果表明,五台山种子植物区系成分与北京东灵山、百花山关系最为密切,与长白山关系次之,与关帝山、大青山有一定差异,与太岳山、太行山和中条山差异较大,与太白山差异最明显,这主要由它们的生态地理条件、区系成分的组成及植被建群种和优势种等差异所决定。 相似文献