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971.
Current silvicultural treatments in beech forests are aimed at achieving thick logs without discoloured hardwood. Therefore
intensive thinning is applied already in younger stands with the objective of large-sized trunks at an age of 100 years. However,
this approach bears the risk that dead wood structures and broken trees are completely removed from the forest. The impact
of three different silvicultural management intensity levels on wood-inhabiting fungi over decades was investigated in a large
beech forest (>10,000 ha) in southern Germany in 69 sampling plots: A Intensive Thinning and Logging with high-value trees,
B Conservation-Oriented Logging with integration of special structures such as dead wood and broken trees and C Strict Forest
Reserves with no logging for 30 years. The analysis of community showed marked differences in the fungus species composition
of the three treatments, independent of stand age. The relative frequencies of species between treatments were statistically
different. Indicator species for naturalness were more abundant at sites with low silvicultural management intensity. Fomes fomentarius, the most common fungus in virgin forests and strict forest reserves, is almost missing in forests with high-management intensity.
The species richness seemed to be lower where intensive thinning was applied (P = 0.051). Species characteristic for coarse woody debris were associated to low management intensity, whereas species with
a significant preference for stumps became more frequent with increasing management intensity. A total amount of dead wood
higher than 60 m3/ha was found to enable significantly higher numbers of species indicators of naturalness (P = 0.013). In conclusion, when applying intensive silvicultural treatment, the role of dead wood needs to be actively considered
in order to maintain the natural biocoenosis of beech forests. 相似文献
972.
The focus of foreign direct investment (FDI) in the global forest sector has shifted from developed to developing economies (currently accounting 73% of total) during the past two decades. China has been the main global driver with its annual FDI soaring from USD 130 million in 2002 to USD 550 million in 2010. In light of international economic and business theories, choice of foreign entry mode is considered the most critical issue in corporate expansion strategy, which, however, has not been empirically studied in the forest sector. To fill this gap, our paper focuses on modeling two equity-based entry mode choices (i.e. wholly owned subsidiary or joint ventures) of foreign investment projects in China based on data from 109 activities of the Top 100 forest, paper, and packaging industry companies. By using logistic modeling, the main determinants of corporate entry mode choice are found to be cultural and geographical distance between the corporate home country and China, duration of corporate presence in China, and spatial concentration of local-level forest industry. Instead, investment project size and local resource availability are found to have no significant impact on corporate entry mode choice in China. 相似文献
973.
Liu
Xianyin China Forestry Publishing House Beijing Xu Huacheng Zheng Junbao Beijing Forestry
University Hebei Forestry College Baoding 《中国林学(英文版)》1994,(1)
LandscapePatternsandDynamicsinShanhaiguanForestFarm,HebeiProvinceLiuXianyinChinaForestryPublishingHouse,BeijingXuHuachengZhen... 相似文献
974.
林分系统的演变,必定是通过净生长量和死亡量的涨落,改变旧的(株数-蓄积量)结构,形成新的转化功能,再发生新的涨落,策动着将来的(株数-蓄积量)演变,这种生长运动导致林分的进化、发展,维持着非平衡态结构的稳定、有序。林分系统的时、空演变是多样化的,而坐标上运动的方向和速度,既表现了林分结构的变化,又反映着能量演变的频率和动量产生的波长,说明演变具有波、粒二象性的特性。 相似文献
975.
杨梅岭林场混交林调查初报 总被引:8,自引:0,他引:8
对霞浦县杨梅岭林场杉木、马尾松混交林和杉木、柳杉混交林初期生长的实地调查表明,10年生杉木、柳杉混交林的单位蓄积量比杉木、马尾松混交林大72.2%,比杉木纯林大2.4倍,为较为成功的混交方式。 相似文献
976.
977.
AStudyonWaterExchangeinRootZoneofProtectiveForestEcosysteminLoessAreaYuXinxiaoCollegeofSoilandWaterConserration,BeijingForest... 相似文献
978.
979.
980.
浅谈当前森林覆盖率计算的两个公式 总被引:1,自引:0,他引:1
介绍计算森林覆盖率的2个公式,指出应该用(2)式计算森林覆盖率.分析了有林地面积、国家特别规定灌木林地面积、灌木林地面积与森林覆盖率的关系. 相似文献