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1.
Wu  Jianguo  Hobbs  Richard 《Landscape Ecology》2002,17(4):355-365
Landscape ecology has made tremendous progress in recent decades, but as a rapidly developing discipline it is faced with new problems and challenges. To identify the key issues and research priorities in landscape ecology, a special session entitled “Top 10 List for Landscape Ecology in the 21st Century” was organized at the 16th Annual Symposium of the US Regional Association of International Association of Landscape Ecology, held at Arizona State University (Tempe, Arizona, USA) during April 25–29, 2001. A group of leading landscape ecologists were invited to present their views. This paper is intended to be a synthesis, but not necessarily a consensus, of the special session. We have organized the diverse and wide-ranging perspectives into six general key issues and 10 priority research topics. The key issues are: (1) interdisciplinarity or transdisciplinarity, (2) integration between basic research and applications,(3) Conceptual and theoretical development, (4) education and training, (5)international scholarly communication and collaborations, and (6) outreach and communication with the public and decision makers. The top 10 research topics are: (1) ecological flows in landscape mosaics, (2) causes, processes, and consequences of land use and land cover change, (3) nonlinear dynamics and landscape complexity, (4) scaling, (5) methodological development, (6) relating landscape metrics to ecological processes, (7) integrating humans and their activities into landscape ecology, (8) optimization of landscape pattern, (9)landscape sustainability, and (10) data acquisition and accuracy assessment. We emphasize that, although this synthesis was based on the presentations at the“Top 10 List” session, it is not a document that has been agreed upon by each and every participant. Rather, we believe that it is reflective of the broad-scale vision of the collective as to where landscape ecology is now and where it may be going in future. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
2.
Integrated pest management (IPM) is facing both external and internal challenges. External challenges include increasing needs to manage pests (pathogens, animal pests and weeds) due to climate change, evolution of pesticide resistance as well as virulence matching host resistance. The complexity of designing effective pest management strategies, which rely less heavily on the use of conventional pesticides, is another external challenge. Internal challenges include organizational aspects such as decreasing trend in budget allocated to IPM research, increasing scarcity of human expertise, lack of knowledge transfer into practice and the communication gap both at country level and between countries, and lack of multi-, inter- and transdisciplinary IPM research. There is an increasing awareness that trans-national networking is one means to overcome such challenges and to address common priorities in agriculture. A large number of stakeholders (researchers, policy makers, growers and industries) are involved in the sector of crop protection, which needs to be coordinated through effective communications and dynamic collaboration to make any IPM strategy successful. Here we discuss a decade-long IPM networking experiences in Europe emphasizing how IPM research, implementation and adoption in Europe may benefit from a broader level networking.  相似文献   
3.
养蜂业作为现代农业的重要组成部分,具有投入少、见效快、不占用耕地、不污染环境的特点。蜜蜂授粉还可以较大幅度提高农作物的产量和品质,促进农业实现健康、绿色和高质量发展。基于外部性理论及兼顾产业内外部效益,利用国家蜂产业体系固定观察点调研资料、蜂蜜市场价格调查和UNComtrade数据,分析了我国蜂业发展概况、生产模式、布局和发展特征,研判养蜂业面临的挑战,探讨其战略定位。研究表明,定地养殖规模相对较小但投入低,大转地养年运输距离最大可达1.5万km且单群收益最高。专业化、机械化和组织化是促进近年蜂农饲养规模稳步提高的主要因素。当前养蜂业面临3个方面的挑战:出口利润直降,高品质蜂产品生产技术与市场双重考验,大田有偿授粉机制尚未建立。因此,从增加农业农村经济和全社会福利的视角,充分发挥养蜂业在农业绿色、生态和高质量发展中的关键作用,提出战略定位和相应的政策。应着眼于专业蜂农生产技术水平提升,积极探索蜂业与种植业的耦合发展的模式,强化养蜂业外部性功能,以标准分级推动优质优价体系,以提升产业内部效益。  相似文献   
4.
与现代农业发展的新要求结合,通过对莘县70 年来农业发展取得的成就、经验的总结,深入 剖析莘县农业当前所面临的挑战,并从发展“绿色生态”农业,促进农业可持续发展、发展“三型特色” 农业,提升农产品竞争力、发展“品牌信息”农业,提高农产品影响力、实施“科技兴农”战略,促进农业 高质量发展、坚持“依法治农”策略,完善相关法规体系建设、实施“人才强农”战略,加强农业高层次人 才培养等方面,就莘县农业发展思路与对策进行了深入思考。  相似文献   
5.
从宁夏产业结构、能源结构等内在因素和国家加大节能减排力度、国际上减缓温室气体排放等外部因素,分析宁夏发展低碳经济的必要性和紧迫性。低碳经济会延缓宁夏的工业化发展,打破现有经济结构,提高发展门槛。同时,低碳经济也给宁夏带来一次深层调整产业结构的机会,促进风能、太阳能发电等低碳产业的发展,凸显其后发优势。由此提出,优化能源结构提高能源利用效率,调整产业结构促进低碳型产业的发展,出台政策创建利于形成低碳经济发展模式的软环境,加强植被建设和土被保护提高碳汇能力,争取空间为解决发展与环境矛盾创造条件等低碳经济发展措施。  相似文献   
6.
中国加入WTO之后,农业将面临许多新的机遇与挑战,农业发展必须要采取一些新的对策,我们应当有所准备。  相似文献   
7.
当前农民的就业问题成为“三农”中最突出的问题。加入WT()后,我国进一步置身于全球化之中,这势必会对农村劳动就业产生深远的影响。本文分析了全球化背景下中国农村劳动就业形势,并针对全球化对农村就业的冲击提出相应对策。  相似文献   
8.
着重分析了在青藏高原气候呈现"暖湿化”趋势下,生态建设面临的各种挑战和机遇,同时给出了林业生态建设应对气候暖湿化的措施,以期为西藏生态建设的规划和实施提供借鉴。  相似文献   
9.
Ethiopia has a large and diverse population of small ruminants, which contribute substantially to the livelihood and income of the rural poor and the country at large. However, the sector faces a number of challenges. Productivity per animal and flock offtake are both very low. Reasons attributed for the apparent low productivity are as follows: absence of appropriate breeding programmes, lack of technical capacity, inadequate and poor‐quality feeds, diseases leading to high lamb mortality, and underdeveloped markets in terms of infrastructure and information. Historically, sheep and goats have received little policy or investment attention. Genetic improvement of small ruminants could contribute to bridging the productivity gap. In the past, the government of Ethiopia has placed much emphasis on importing exotic genetics and cross‐breeding with local stock as a strategy for genetic improvement. However, this has not led to a significant productivity improvement and the programmes have generally been unsustainable. Currently, there is a change in approach and a recognition of the need to focus genetic improvement efforts on the local genetic resources that are well adapted to the diverse agro‐ecologies and production environments in the country. Community‐based breeding programmes (CBBPs), which focus on indigenous stock and consider farmers’ needs, views, decisions and active participation, from inception through to implementation, have been identified as programmes of choice. The Ethiopian government and the private sector need to invest in strategic areas around CBBPs to make the programme work for the poor and be sustainable in low‐input systems.  相似文献   
10.
本文通过归纳南海各渔业区的渔业资源特点及国内渔业管理现状,提出了当前南海渔业资源及其管理面临的主要挑战。南海为我国渔业资源最富饶的海域之一,然而南海北部渔业区重要经济种类正面临资源开发过度的严峻形势。南海外海开发潜力巨大,但迫切需要及时丰富和优化渔业资源调查评估和手段。有关南海目前的渔业管理现状,休渔制度的实行使得开捕后的多种主要经济物种资源有所恢复,但效果有限,仍需未来更多的研究和调查数据来论证休渔制度的效果。人类活动、气候变暖及海洋酸化、资源评估手段较为单一和落后等问题,为南海渔业资源的管理和养护带来巨大挑战。制定合理的渔业资源养护和管理措施,开展持续的资源调查以及引入合适的资源评估手段,对实现南海渔业资源的可持续利用具有重要意义。  相似文献   
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