不同放牧制度对高原鼢鼠活动区高寒草地群落结构影响

为探讨不同放牧制度对高原鼢鼠的生物调控机制,本研究以高原鼢鼠（Myospalax baileyi）危害严重的天然草场为研究对象,通过网围栏设置禁牧区、季节性放牧区及自由放牧区,分析草地群落结构及高原鼢鼠种群密度与单子叶、阔叶类植物的相关性。结果表明：禁牧区禾本科植物重要值两年均高于季节性放牧和自由放牧区。3个样区的多样性指数在第二年都有所增加;同时,自由放牧区第一年的优势度指数和均匀度指数高于季节放牧区和禁牧区;季节性放牧第二年草地群落多样性指数高于禁牧区和自由放牧区,同时季节性放牧区的优势度指数显著高于禁牧区和自由放牧区（P<0.05）。另外,禁牧区单子叶植物地上生物量最高,季节放牧区阔叶类植物地下生物量最高。高原鼢鼠相对鼠群密度表现为：季节性放牧区>自由放牧区>禁牧区,且禁牧区高原鼢鼠相对种群密度与单子叶植物地上生物量、阔叶类植物地下生物量呈正相关;季节性放牧区的相对鼠群密度与地上生物量呈负相关,与地下生物量呈正相关;自由放牧区的相对鼠群密度与单子叶植物地上生物量呈负相关,与单子叶植物地下生物量、阔叶类植物生物量（地下、地上）均呈正相关。综上所述,建立合理的放牧制度可以改善高寒草甸草地群落结构,进而调控高原鼢鼠的种群密度。     

社会转型期档案工作的新思路——论档案工作“两个体系”建设的理论内涵、时代意义和实现途径

实现“两个转变”、建立“两个体系”是新时期我国档案工作的新战略,现从理论内涵、时代意义和实现途径等方面对其进行全方位分析,探讨不同实践主体在建立“两个体系”中的职责和任务,为促进“两个体系”建设目标的实现提供参考。     

Pre-harvest survival of codling moth in artificially infested sweet cherry fruits

Prior to the 2009 season, sweet cherry fruits, Prunus avium (L.) L., from North America were required to be fumigated with methyl bromide before being exported to Japan to eliminate possible infestation by codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae). However, based on recent biological research on host status, a new procedure (the “systems approach”) was implemented relying on the cumulative effects of pre- and post-harvest practices to produce pest-free sweet cherry fruits for export. This is an organized process that involves the integration of procedures used in the production, harvest, packaging, and distribution of a commodity which cumulatively meet the requirements for quarantine security. The objective of our study was to provide additional information to support the systems approach for codling moth in sweet cherries fruits. For four seasons, branches with sweet cherry fruits were caged on trees and infested by released ovipositing codling moths into the cages. Fruits were sampled weekly for codling moth individuals at each life stage. Eggs were laid mostly on leaves with the seasonal average numbers per cage ranging from 142 to 617. Populations declined rapidly after egg eclosion, with <1.5% of the original cohort surviving to fifth instars. Even after 8 weeks, none had formed cocoons or pupated. This failure of the codling moth to complete a life cycle under field conditions supports previous life history studies and demonstrates that sweet cherry fruits are inadequate hosts for codling moth.     

基于项目的Java课程综合实训设计

本文介绍了医院管理软件要实现的功能及对系统进行的总体设计、系统功能模块设计及数据库设计,描述软件设计过程中的主要技术细节。     

冬小麦根系各级分枝形成及其解剖结构研究

从池栽、盆栽和大田取根,系统观察高产小麦各级分枝根形成和解剖结构.结果表明,小麦根系经由分枝,初生根可达6级,次生根可达5级.各级分枝根解剖结构的差异主要是皮层细胞层数和中柱维管束数目的不同.小麦分蘖期以后继续发生的根,如果土壤条件适宜,植株生长健壮,其根皮层可一直维持正常状态到抽穗期,抽穗后根皮层将逐渐萎缩.高     

Productivity and Costs in Shelterwood Harvesting

Harvesting costs have a significant influence on the application and potential use of the shelterwood system. These costs are strongly related to the time needed for the logging operations. In this study, which was carried out in Norway spruce [Picea abies (L.) Karst.] stands in northern Sweden, the effective time (E ₀) of a single-grip harvester in shelterwood cutting, thinning of shelterwoods and clearcutting was measured. Based on these data the costs of shelterwood harvestings and clearcutting were calculated and compared. It was found that (1) the time per tree in shelterwood cutting and thinning of shelterwoods was greater than in clearcutting, (2) the time per cubic metre was higher in sparse shelterwoods than in dense shelterwoods, (3) most of this increase was due to longer driving time because fewer trees were harvested, and (4) the longer time and higher logging costs in the shelterwood system (compared with the clearcutting system) were mostly related to the establishment of the shelterwood. It was concluded that the shelterwood alternative is especially competitive when it is desirable to maximize the share of saw logs at the expense of pulpwood.     

开发适宜性视角的农业文化遗产地旅游资源评价框架——以浙江省庆元县为例

旅游资源评价是农业文化遗产旅游开发与有效保护的前提,评价结果对于遗产地资源管理与可持续利用具有重要影响。文章基于农业文化遗产旅游资源的开发适宜性视角,从资源要素价值、时间适宜性和空间适宜性3个维度,选取历史文化价值、艺术观赏价值、科学研究价值、自然环境、资源规模潜力、游客舒适度和交通可达性7个层面的15个指标,通过层次分析法和熵值法确定组合权重,运用多因子加权评价模型和GIS空间分析方法,并以浙江省庆元县香菇文化系统为例,对农业文化遗产旅游资源进行评价。结果表明:庆元县农业文化遗产旅游资源开发适宜性空间上总体呈"中间高,四周低"的格局。其中,中部地区的松原镇、五大堡乡、四山乡、贤良镇和百山祖乡的旅游资源优势突出,是开发潜力最大的地区;南部地区的安南乡、举水乡、岭头乡和龙溪乡尽管形成了一定规模的自然旅游资源,但由于交通可达性较差,降低了旅游开发适宜度;东部地区的左溪镇、官塘乡和江根乡可供开发的旅游资源较少,因而旅游开发适宜度不高。从时间分布上看,春末(4月和5月)及秋季(10月)是庆元香菇文化资源旅游开发的最佳时期。为增强南部和东部地区旅游资源开发的适宜度,建议进一步加强该区的交通基础设施建设,提高区域之间的交通通达度;同时,采取多种资源组合的开发方式,增加游客的适游时间。基于开发适宜性视角构建农业文化遗产旅游资源评价框架,可为农业文化遗产地旅游资源价值分析、旅游开发实践提供理论支撑和方法指导。     

农业文化遗产的保护与发展

农业是国民经济和社会发展的基础。悠久的农业文明创造了一批经济与生态价值高度统一的土地利用系统,体现了独特的动态保护思想以及农业可持续发展的理念,对于现代生态农业的发展具有重要的价值。2002年联合国粮农组织发起了"全球重要农业文化遗产"保护项目,并在全世界得到迅速开展。本文介绍了全球重要农业文化遗产的概念内涵及其项目进展,分析了农业文化遗产在促进农业多种功能、促进传统知识与现代技术的融合、促进农村可持续发展方面的重要作用。在此基础上,分析并总结了我国农业文化遗产保护与发展的现状与面临的问题,最后从科学研究和管理实践两个角度对我国农业文化遗产的保护与发展工作提出了建议。     

全球重要农业文化遗产-青田县稻鱼共生系统保护与可持续发展之思考

浙江青田县龙现村稻鱼共生系统作为全球重要农业文化遗产,其保护和可持续发展的问题现已引起了社会的关注。在调查研究的基础上,分析了青田县龙现村稻鱼共生系统得以长期延续的历史渊源、自然环境条件和人文社会因素等原因。同时,指出了这种稻鱼共生模式在当今市场经济条件下面临的挑战与问题,如市场问题、产业化问题、旅游业发展导致的环境问题、农业文化消失问题等。最后提出了一系列对策措施,如加强全村生态规划,建立稻鱼共生自然保护区,打造稻鱼生产品牌,适度发展农业生态旅游,建立多方参与机制等措施。     

The impacts of climate change on livestock and livestock systems in developing countries: A review of what we know and what we need to know

Despite the importance of livestock to poor people and the magnitude of the changes that are likely to befall livestock systems, the intersection of climate change and livestock in developing countries is a relatively neglected research area. Little is known about the interactions of climate and increasing climate variability with other drivers of change in livestock systems and in broader development trends. In many places in the tropics and subtropics, livestock systems are changing rapidly, and the spatial heterogeneity of household response to change may be very large. While opportunities may exist for some households to take advantage of more conducive rangeland and cropping conditions, for example, the changes projected will pose serious problems for many other households. We briefly review the literature on climate change impacts on livestock and livestock systems in developing countries, and identify some key knowledge and data gaps. We also list some of the broad researchable issues associated with how smallholders and pastoralists might respond to climate change. The agendas of research and development organisations may need adjustment if the needs of vulnerable livestock keepers in the coming decades are to be met effectively.