Irrigation and Participation: Rehabilitation of the Rajapur Project in Nepal

Rajapur is one of the world's largest farmer-managedirrigation systems, but it suffers badly from flood damage.This 15,000 ha project has now been rehabilitated withoutchanging the traditional management arrangements. The workswere planned carefully with effective participation, andindigenous organisations strengthened to help them cope withmore modern structures. The project was implemented over a 10-year period, and was adapted throughout this time as farmerrequirements and aspirations were better expressed andunderstood. This willingness to change the project wasfundamental to its success, and highlighted several key issueswhich will help planning similar projects in the future,making participation a reality and not mere rhetoric.     

Reconciling traditional inland fisheries management and sustainability in industrialized countries, with emphasis on Europe

In northern industrialized countries, the inland fisheries sector has long been dominated by recreational fisheries, which normally exploit fish for leisure or subsistence and provide many (poorly investigated) benefits to society. Various factors constrain the development and existence of inland fisheries, such as local user conflicts, low social priority and inadequate research and funding. In many cases, however, degradation of the environment and loss of aquatic habitat are the predominant concerns for the sustainability of inland fisheries. The need for concerted effort to prevent and reduce environmental degradation, as well as conservation of freshwater fish and fisheries as renewable common pool resources or entities in their own right is the greatest challenge facing sustainable development of inland waters. In inland fisheries management, the declining quality of the aquatic environment coupled with long‐term inadequate and often inappropriate fisheries management has led to an emphasis on enhancement practices, such as stocking, to mitigate anthropogenic stress. However, this is not always the most appropriate management approach. Therefore, there is an urgent need to alter many traditional inland fisheries management practices and systems to focus on sustainable development. This paper reviews the literature regarding the inputs needed for sustainability of inland fisheries in industrialized countries. To understand better the problems facing sustainable inland fisheries management, the inland fisheries environment, its benefits, negative impacts and constraints, as well as historical management, paradigms, trends and current practices are described. Major philosophical shifts, challenges and promising integrated management approaches are envisaged in a holistic framework. The following are considered key elements for sustainable development of inland fisheries: communication, information dissemination, education, institutional restructuring, marketing outreach, management plans, decision analysis, socioeconomic evaluation and research into the human dimension, in addition to traditional biological and ecological sciences. If these inputs are integrated with traditional fisheries management practices, the prospects for sustainability in the inland fisheries will be enhanced.     

Genetic diversity and parentage in farmer selections of cacao from Southern Sulawesi,Indonesia revealed by microsatellite markers

Indonesia is the third largest cocoa-producing country in the world. Knowledge of genetic diversity and parentage of farmer selections is important for effective selection and rational deployment of superior cacao clones in farmers’ fields. We assessed genetic diversity and parentage of 53 farmer selections of cacao in Sulawesi, Indonesia, using 152 international clones as references. Cluster analysis, based on 15 microsatellite markers, showed that these Sulawesi farmer selections are mainly comprised of hybrids derived from Trinitario and two Upper Amazon Forastero groups. Bayesian assignment and likelihood-based parentage analysis further demonstrated that only a small number of germplasm groups, dominantly Trinitario and Parinari, contributed to these farmer selections, in spite of diverse parental clones having been used in the breeding program and seed gardens in Indonesia since the 1950s. The narrow parentage predicts a less durable host resistance to cacao diseases. Limited access of the farmers to diverse planting materials or the strong preference for large pods and large bean size by local farmers, may have affected the selection outcome. Diverse sources of resistance, harbored in different cacao germplasm groups, need to be effectively incorporated to broaden the on-farm diversity and ensure sustainable cacao production in Sulawesi.     

Preservation and Reuse of the Architectural Heritages in the Wave of Urban Construction -Taking Harbin for Example

Preservation of architectural heritages is a very important problem of urban construction in Harbin. After summing up the preserving work in Harbin, the opinions about the work of preserving and reusing the architectural heritages are proposed in this paper. It points out that the legislation is the key in architectural heritage preservation.     

Studies on the Efficacy of Various Insecticides Against Mustard Aphid [Lipaphis erysimi (Kalt)]

Abstract

An experiment was designed to test the efficacy of various insecticides for the control of mustard aphid (Lipaphis erysimi (Kalt)) on mustard (Brassica juncea), variety RL 18 at the Research Farm of the Haryana Agricultural University, Hissar (India). Out of the 13 insecticides tried, each at two levels, it was found that methyldemeton 250 ml and menazon 250 g a.i. gave the maximum control of mustard aphid. Maximum yield of 1111 kg/ha was obtained with methyldemeton 250 ml (a.i./ha) against 360 kg/ha of the control.     

Tree species diversity,species regeneration and biological productivity of seeded Acacia catechu Willd. In rehabilitated limestone mines in the North West Indian Himalayas

Degraded sites like mine spoils on hillslopes are characterized by poor soil physico‐chemical environments and instability. Reclamation of such areas using low cost bioengineering and vegetative methods were carried out in an abandoned limestone mine in the lower western Indian Himalayas and the impact of these measures on vegetation diversity, secondary succession and growth of seeded Acacia catechu Willd. after two decades of protection are reported in this paper. Results reveal that introduction of fast growing leguminous species affected species diversity and hampered the regeneration and growth of native vegetation, due to the dense shade of the over‐storey component. Species diversity (H') levels increased with the opening of the canopy at different elevations, with the highest diversity (1·624) being recorded on the hilltop with Acacia catechu and Wedlandia exserta dominating the area. Enumeration of various species in the growth stages indicated a large population in the pole stage followed by tree and sapling stage indicating scattered regeneration mostly by 1‐2 species. Tree associations in the lower, middle and upper reaches were of Leucaena leucocephala—A. catechu, A. catechu—Boehemeria rugulosa and A. catechu‐W. exserta, respectively. Seeded A. catechu plants now in the tree stage have attained an average height of 5·5 m and dbh of 10·44 cm with an average wood volume of 0·027 m³ in a period of 16–21 years. At current prices of heartwood (US $435 per m³) of A. catechu which is used in the manufacture of ‘kattha’, the investments made two decades ago (US$ 13043) in the rehabilitation of the limestone mine are fairly justified. Copyright © 2010 John Wiley & Sons, Ltd.     

人工生境缀块对受损河岸生态系统的修复作用

利用生态工程学方法,在长春市西小沿子河研究了人工生境缀块对受损河岸生态系统的修复作用.结果表明,实验区经过人工生态修复和近4年的自然演替,新增加了3个草本植物种,植物群落结构得到优化,形成了较为稳定的乔-灌-草群落结构,植被覆盖率达到95%以上,为动物提供了栖息空间.生境缀块内的土壤微生物数量、土壤生化作用强度、土壤酶活性、有机质含量、全N、全K、底栖动物种类及数量均较对照区增加,其中微生物数量、呼吸强度、纤维分解强度、固氮作用强度、过氧化氢酶活性、脲酶活性和有机质含量均达到显著差异水平（P＜0.05）.人工生境缀块使受损河岸的稳定性增加,改善了河岸生态系统功能,使生态系统发生正向演替,土壤环境向良性方向发展,同时成功地控制了土壤侵蚀.生态护岸不仅降低经济成本,而且具有生态价值、环境价值、景观价值、教育价值和社会价值,为混凝土河岸的生态改造和受损河岸的生态修复提供了新的模式.      

农业活动对景观格局的影响

景观格局是自然和人类共同作用的结果,并随着经济发展和人口增长,农业活动在景观格局中起着愈来愈大的作用。放牧过程导致土壤退化和生物群落的不稳定,间歇式放牧会提高物种丰富度,促进生态系统的进化;植树造林不但有利于生态恢复和重建,而且对经济建设有巨大作用,更是保护生物多样性的手段;农作物种植包括物理干扰和化学干扰过程,改变了微生物的活性,同时对土壤性质产生影响;土地整理是人为的、强制性、时效性强的一种干扰,能在短期内对生态系统及景观格局产生剧烈影响,通过调整景观结构、改善景观破碎化,改变农业土地利用结构,使得社会效益、生态效益和环境效益均有所增加。     

国内外河流生态修复相关研究进展

河流生态系统是一个复杂、多变、非线性的系统,增加了河流生态修复工作的难度。如何真正修复河流生态系统,国内外许多学者进行了大量的理论和实践研究,取得丰硕的成果和宝贵的经验。总结国外城市化对河流生态的影响、河流生态修复技术、河流生态评价及河流生态修复后评估方面的成果,旨在为我国正在广泛开展的水生态修复工作提供参考;总结国内河流生态修复已有的成果和存在的问题,并展望我国今后河流生态修复工作应重点开展的工作内容。