全文获取类型
收费全文 | 384篇 |
免费 | 6篇 |
国内免费 | 6篇 |
专业分类
林业 | 60篇 |
农学 | 12篇 |
基础科学 | 21篇 |
10篇 | |
综合类 | 241篇 |
农作物 | 12篇 |
水产渔业 | 3篇 |
畜牧兽医 | 23篇 |
园艺 | 12篇 |
植物保护 | 2篇 |
出版年
2023年 | 3篇 |
2022年 | 2篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 8篇 |
2015年 | 10篇 |
2014年 | 10篇 |
2013年 | 45篇 |
2012年 | 52篇 |
2011年 | 54篇 |
2010年 | 15篇 |
2009年 | 14篇 |
2008年 | 26篇 |
2007年 | 29篇 |
2006年 | 21篇 |
2005年 | 17篇 |
2004年 | 13篇 |
2003年 | 6篇 |
2002年 | 9篇 |
2001年 | 6篇 |
2000年 | 8篇 |
1999年 | 6篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1988年 | 1篇 |
排序方式: 共有396条查询结果,搜索用时 31 毫秒
81.
82.
鹑梭状芽胞杆菌外毒素的分离与特性研究 总被引:1,自引:0,他引:1
用色氨酸磷酸液体培养基厌氧培养, 蔡氏滤器过滤, 以饱和硫酸铵沉淀, 制备了鹑梭状芽胞杆菌外毒素, 经检测该毒素的稳定性较差, 60 ℃10 分钟即可破坏, 经 S D S聚丙烯酰胺凝胶电泳分析证明, 该毒素至少有11种蛋白成分, 分子量在30000 ~67000 之间, 静脉注射小鼠02 m g 可引起死亡, 经口灌服雏鸡, 可出现肝脏坏死和肠粘膜溃疡。 相似文献
83.
《Southern Forests》2013,75(4):381-389
One of the dominant challenges facing the South African forestry sector is the issue of land restitution. The aim of this study was, therefore, to assess the perception of beneficiaries of benefit-sharing modalities for forest-based land reform initiatives in their locality. A random sampling technique selected 140 and 175 households in Amabomvini and Cata communities in KwaZulu-Natal and Eastern Cape provinces, respectively. The household beneficiaries showed a lack of knowledge of the criteria used for the disbursement of the benefits. In addition, over 70.0% of household beneficiaries in Amabomvini, compared with far less than 70.0% in Cata, preferred using rental income for infrastructure development in their respective communities. The results further showed that the relationship between the responses of the respondents from both Amabomvini and Cata communities regarding their perception on the existence of the criteria established to share the benefits, was statistically significant (χ2 = 34.452, df = 4, p < 0.005). However, a lack of transparency, trust and greed were among the factors that household beneficiaries identified as the root causes to the poor benefit-sharing mechanisms. Therefore, it is recommended that there should be political will and commitment from government in order to ensure the development and strengthening of existing benefit- sharing policies for the improvement of livelihoods of the land beneficiaries. 相似文献
84.
85.
依据《森林法》、《少数民族区域自治法》和少数民族林业发展实际,论述了民族自治地方实行林业生产建设的优惠政策及少数民族地区林权争议的类型,提出了六条解决少数民族地区林权争议的原则。 相似文献
86.
Gerhard Weiss Suzanne Martin Anne Matilainen Birger Vennesland Carmen Nastase Erlend Nybakk Laura Bouriaud 《Small-Scale Forestry》2007,6(4):423-442
This article examines innovation processes in forest recreational services on the basis of case studies in five European countries
with differing institutional backgrounds of forest ownership and access rights. The analysis reveals that forest-related recreation
services are developed under varying institutional conditions and on public as well as private land. Ideas for innovations
in recreational services may come from within but often outside the forestry sector. Financing is provided from public and
private sources. Both public and private spheres have important roles in providing natural, human and financial resources
and usually a network of public and private actors are involved in innovation processes. Of particular importance are cross-sectoral
interactions between forestry and tourism. Greater institutional support is needed for the development of forest-related recreation
services because the field is at an early stage of development. It is concluded that support should focus on providing ideas
and financial resources for product development and on facilitating cross-sectoral interaction between forestry and tourism
actors. A particular need is seen for development of models for durable interaction between land owners and tourism operators
on a regional scale. 相似文献
87.
建立与集体林权制度改革相适应的光泽县森林经营和森林防火新机制 总被引:2,自引:0,他引:2
通过分析光泽县集体林权制度改革后的林业现状和问题,探索闽北林区森林经营管理和森林防火新机制,提出新时期森林经营的总体目标是构建巩固林权制度改革成果的五大配套体系(资源培育和管理体系、森林集约化经营和管理体系、林业科技和技术服务体系、森林防火体系、森林病虫害防治体系)。 相似文献
88.
89.
90.