农民协会的制度需求和供给分析

农民协会在我国有着100多年的历史,在现阶段重建农民协会对建设社会主义新农村有着深远的意义.然而,重建农民协会却面临着如何保障和规制其发展的难题.随着农村市民社会的兴起和农村民主政治的发展,具有鲜明"第三部门"特点的农民协会在农村市民社会和政治国家之间可以起到缓冲作用,制定一部《农会法》对于稳定、持续地发挥农民协会的该缓冲作用有着十分重要的价值.     

Temperature,discharge and development shape the larval diets of threatened green sturgeon in a highly managed section of the Sacramento River

Feeding at early fish life stages is a key determinant of survival to recruitment. To understand the environmental and developmental determinants of early life stage feeding in ESA‐threatened green sturgeon (Acipenser medirostris), we performed a diet study in a highly managed section of California's Sacramento River, where temperature and discharge are controlled by dam releases. Utilising field collections from 2012 to 2016, we assessed the impacts of temperature, discharge and morphological development on the composition and number of prey items in larval green sturgeon diets. Results show that there are more empty stomachs at colder temperatures. Higher discharge conditions decreased prey taxon richness and counts, especially the abundance of cyclopoid copepods in diets. Fish smaller than 30 mm had teeth on the oral jaws and showed a strong reliance on zooplankton prey. The developmental loss of teeth in fish greater than 30 mm was associated with decreased zooplankton consumption and increased richness of benthic macroinvertebrates in diets. Our results show that river management through dam releases has the potential to impact the earliest life stage of green sturgeon by reducing the prevalence of favoured zooplankton prey in diets.     

Stem and Crown Relations in Four Species from an Evermoist Forest in Sri Lanka

Abstract

The volume of a tree's crown represents the accumulated historic crown surfaces integrated over time and environmental conditions. As such the crown volume of a tree should be correlated to the stem diameter, which represents accumulated historic wood increment. This study examines the relationship between crown and stem metrics of four tree species, Macaranga peltata, Schumacheria castaneifolia, Shorea megistophylla, and Shorea trapezifolia, from an evermoist forest in southwestern Sri Lanka. Shorea megistophyllahad the highest correlation between crown volume and stem diameter of the four species (r² = 0.55). The addition of an inverted parabola, to represent historic crown surfaces not included by the current crown volume, improved correlations with stem diameter significantly, especially in the flat-topped pioneer species, Macaranga peltata. Schumacheria castaneifoliashowed poor correlations between stem and crown dimensions, suggesting that allocation to fruit and flower production may receive higher priority than diameter growth. The relative importance of current crown volume and cumulative crown volume in explaining variation in stem diameter offers insight into species life-history patterns.     

The privatisation of New Zealand forests

During the 1980s and early 1990s, the New Zealand economy went through radical economic changes, overhauling almost all aspects of economic policy. The New Zealand Forest Service was not exempt from these changes. This paper describes two major aspects of that change: the way the New Zealand Forest Service, like many other state trading activities, was restructured first through corporatisation under the State-Owned Enterprises Act 1986 which has ultimately led to privatisation; and secondly through the enactment of the New Zealand Resource Management Act 1991 which has fundamentally altered environmental management in New Zealand. The Act's underlying principle is based on the principle of sustainable management. This principle forms the foundation of forest management in New Zealand. Whether the restructuring and privatisation will produce a more efficient forestry sector is an issue that the author does not address. The Crown Assets sales are an ongoing and dynamic process which still have not been completed. This is a shortened version of a chapter originally presented in her LL.M. Thesis in 1995.     

BMBF-research-focus ‘percolation water prognosis’ concept and current activities

The 41 participants of the BMBF-research-focus ‘percolation water prognosis’ are working out the scientific basis of the methods, which are needed to carry out this ‘percolation water prognosis’. They are either focussing on the further development of methods for determining the source strength of materials or on improving existing models for predicting the contaminant transport through soils. Validity and transferability of these developed methods/models are evaluated by including the core projects ‘reference materials’ and ‘lysimeter experiments’ . Scientific co-ordination is carried out at the HSL, where — among other activities — a central database will be created to compare and interpret the results of the different projects. A routine procedure for carrying out the ‘percolation water prognosis’ in most cases must be easily applicable and generally accepted. Nevertheless, the research projects are examining the arising questions from different perspectives and apply highly sophisticated methods in order to provide a sound scientific basis [8]. Most of the projects have started in the course of the year 2001, so first results may be expected during 2002.     

Comparative Studies on US Lacey Act Amendment and EU Timber Regulation

The US and EU markets are the main destinations of Chinese forest products.Through analyzing the similarities and differences between the US Lacey Act Amendment and the EU Timber Regulation,the paper focused on how to realize better compatibility and practicality of Chinese timber legality verification scheme in terms of verification standard setting,verification procedures,pilot work of timber legality verification scheme,capacity-building trainings and studies on key problems.     

Ammonia Emissions from Broiler Houses

Air emissions will be one of the greatest challenges facing the poultry industry in the future. Federal regulations as applied to animal agriculture will be further defined as additional baseline data are obtained. Ammonia emissions monitoring requires accurate ventilation estimates, ammonia detection, and trained personnel. There are wide variations in ammonia emissions among houses, ages of birds, and flocks. Ammonia emission levels per house occasionally exceed the threshold of 45 kg /d (100 lb/d) set by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and Emergency Planning and Community Right to Know Act (EPCRA). In the future poultry producers may need to address ammonia emissions when adopting best management practices for their operations.     

美国农产品产地直销支持政策对中国的启示

美国2014农业法案,在营养援助计划、信贷支持、农村发展和园艺支持计划中增加了一些新的支持产地和区域农产品直销的政策和规定.通过对“农民-消费者”和“农场-厂商”包括机构、学校、农场地零售店、餐厅等食品销售渠道的支持,旨在加强消费者与本地和地区食品市场的连接.在整理美国新农业法案对产地和区域食物直销支持政策内容的基础上,对其影响进行评价,进而结合目前我国农产品直销支持政策存在的问题提出其对我国的启示.     

Conservation status of eulachon in the California Current

Eulachon (Thaleichthys pacificus), an anadromous smelt in the Northeast Pacific Ocean was examined for listing under the USA’s Endangered Species Act (ESA). A southern Distinct Population Segment (DPS) of eulachon – that occurs in the California Current and is composed of numerous subpopulations that spawn in rivers from northern California to northern British Columbia – was identified on the basis of ecological and environmental characteristics, and to a lesser extent, genetic and life history variation. Although the northern terrestrial boundary of this DPS remains uncertain, our consensus opinion was that this northern boundary occurs south of the Nass River and that the DPS was discrete from more northern eulachon, as well as significant to the biological species as a whole and thus is a ‘species’ under the ESA. Eulachon have been nearly absent in northern California for over two decades, have declined in the Fraser River by over 97% in the past 10 years, and are at historically low levels in other British Columbia rivers in the DPS, and nearly so in the Columbia River. Major threats to southern eulachon include climate change impacts on ocean and freshwater habitat, by‐catch in offshore shrimp trawl fisheries, changes in downstream flow timing and intensity owing to dams and water diversions, and predation. These threats, together with large declines in abundance, indicate that the southern DPS of eulachon is at moderate risk of extinction throughout all of its range. The southern DPS was listed as threatened under the ESA in May 2010 – the first marine forage fish to be afforded these statutory protections, which apply only to waters under U.S. jurisdiction.     

应对国际林产品贸易面临的新挑战

伴随着林产品贸易规模的扩大, 中国林产品贸易环境面临不断恶化的风险。金融危机、森林认证和雷斯法案构成了中国林产品贸易环境变化的主要因素。如何应对林产品贸易面临的新挑战成为制约中国林产品贸易发展的首要问题。文中首先分析中国林产品贸易环境的构成因素并简要介绍各个因素产生和发展的背景; 在此基础上, 结合中国林产品贸易的实际情况, 对不同因素的影响分别予以分析; 最后, 针对贸易环境不同层次的特点, 提出应对国际林产品贸易环境变化的系统性的政策建议。