不同管理措施对杏园昆虫群落结构的影响

为全面了解杏树林害虫的危害与发生规律,为综合防治提供依据,应用生物多样性指数分析了英吉沙县不同管理措施杏园生态系统中昆虫群落结构特征.结果表明:在3种类型的杏园中有昆虫37种,分别隶属于9目26科;不同杏园昆虫群落的科数、物种数及丰富度均有不同程度的变化;不同生境集中性指数也有一定的差异;各园的优势种主要以剌吸式口器的朝鲜球坚蚧为主;不同杏园昆虫群落及各类群生态优势集中性在不同时段并不一致.     

STUDY ON THE LOG PRODUCTION LINE IN LOG YARD

The article deals with the prduction lines in log yard by investigating the utilizationof machines in forest areas,presents the methods and rules of differentiating the log productionlines and also summarizes the formation and development of three kinds of log production lines innortbeast forest areas of China.It gives different combination types of log production lines andtheir applications, so it is significant for us to evaluate and standardize the log Production lines.     

Management Strategies of Free-Roaming Horses in Alberta Compared with Other Jurisdictions

Management strategies of free-roaming species are subject to polarizing debates around the world. This paper provides perspectives on free-roaming horse management strategies practiced in Alberta and compares them against national management strategies used in Canada and internationally (United States and Australia) to illustrate importance of science-based and socially inclusive management schemes. Owing to their pluralistic status as an introduced and culturally significant species of western Canada, free-roaming horse populations are a contentious environmental management issue in Alberta. Some stakeholders (e.g., indigenous people, horse and animal rights advocates) believe the government aims to extirpate free-roaming horses in favor of cattle grazing. However, the Albertan government and ranchers believe it is important to conserve and manage free-roaming horse populations for all land users while minimizing adverse environmental effects in sensitive foothill and mountain grasslands and associated riparian areas in Alberta. Despite this contention, a systematic approach that is mindful of the history and cultural value of horses to society is required to properly manage this species. Best management practices from case studies were used to compare against four main concerns identified from the literature of free-roaming horse management used in Alberta. Concerns include 1) cultural heritage values, 2) free-roaming (or wild) horse designation, 3) lack of scientifically rigorous population monitoring, and 4) societal considerations. Ecological effects of free-roaming horses and human dimensions of their management are discussed. It is recommended that lessons learned from other jurisdictions be applied to free-roaming horse management in Alberta to provide a more holistic framework as the government develops a “feral horse management strategy.”     

紫金山矿区裸地植被恢复技术研究

选金废渣堆积场的植被恢复是紫金山矿区生态恢复的重点。通过对废矿石(渣)堆边坡的裸地整治、植物选择与配置、栽植和管护等一系列技术措施的研究与探索,形成了工程措施与生物措施并举的快速植被恢复技术,并取得良好的治理效果。     

如何强化与提高贮木场商品化管理水平

近几年，由于森工企业经济不景气，方正林业局从长远目标做起，做好贮木场商品化管理，挖潜增效，面向市场，提高了经济效益。     

人工神经网络在现代农业园区机械化程度综合评估中的应用

通过将人工神经网络应用于现代化农业园区机械化程度的综合评估,介绍了神经网络的评估原理,建立了农业园区机械化程度的评估模型。并用计算实例表明此种方法还具有较好的可靠性     

美国公理会与民国保定乡村建设述论

在二十世纪二三十年代中国开展的乡村建设运动中,除以往被学界重视的民间乡建团体外,关注较少的近代来华传教团体也起了非常重要的作用,尤其是在乡建开展较为出色的保定地区,美国公理会可谓翘楚。该会针对保定乡村落后的现状,在此开办平民学校,推广农业改良并提倡农业教育。这些乡村建设活动虽然带有宗教性的功利动机,在开展过程中也遇到了世俗与宗教相冲突的两难境地,但在部分地区的确改进了民众的生活水平,一定程度上缓解了当地乡村社会面貌。     

Conservation of Zingiber germplasm through in vitro rhizome formation

The effects of various concentrations of maleic hydrazide (MH; 2, 4, 6, 8 mg/l) and three light treatments (16-h, 24-h, 0-h) on in vitro rhizome formation and conservation of ginger (Zingiber officinale Rosc. cv. Rio de Janeiro) were studied. In vitro rhizome formation occurred in all the above treatments. Addition of MH (2–8 mg/l) to the control medium (CM) comprising Murashige and Skoog's (1962) salts, 9% sucrose, 0.8% agar-agar, 0.1 mg/l α-naphthaleneacetic acid (NAA), 1 mg/l N⁶-benzyladenine (BA), did not show any significant positive effects on rhizome formation as well as survival of cultures. A significant effect of light treatments was observed on survival of cultures but not on rhizome formation. More than 50% cultures survived up to 14 months on CM under 16-h and 24-h light conditions as compared to 20% cultures on same medium incubated under dark. A total of 33 genotypes of cultivated and wild species of Zingiber were subsequently tested for conservation through in vitro rhizome formation on CM under 16-h light condition. All genotypes produced rhizomes of varying size with numbers ranging from 3 to 15 per culture and were conserved for at least 12 months; some genotypes could be conserved even up to 16–20 months. Viability of rhizomes was determined by in vitro regeneration of shoots upon subculture and their subsequent establishment in soil. Following the protocol described in the present paper, some 160 genotypes of cultivated and wild species of Zingiber, collected from different geographical regions of India, are being conserved at In Vitro Genebank of National Bureau of Plant Genetic Resources, New Delhi.