中外退耕还林还草比较及其启示

在全面回顾总结世界各国退耕还林还草概况的基础上，论述了中外退耕还林还草的三大不同特点，分析了国外退耕还林还草的历史实践对我国目前正在进行的退耕还林还草试点的四方面启示，以期推动我国退耕还林还草的健康发展。     

关于现有退耕还林还草政策的探讨

退耕还林还草实行“三补两免两落实”政策，解决了当前退耕后农民在一个时期内的生计问题，同时缓解了农民在农业税、生活需要上的经济负担，一定程度地解决了造林种草种苗的费用。总的来讲，退耕还林还草政策较优惠，农民普遍欢迎，有利于退耕还林还草工程的实施。但通过两年来退耕还林还草工程的实施，笔者认为退耕还林还草工程的相关政策在以下几个方面值得完善：一、退耕还林还草面积应以实际水平面积为准实施退耕还林还草工程，要求以实际的水平面积为准，但目前农户的承包面积并非是实际水平面积，而是传统的承包面积，是以指手为界或…     

关于黑龙江省新一轮退耕还林还草工程的几点思考

坡耕地退耕还林还草可有效减少水土流失,改善生态环境。针对新一轮退耕还林还草工程,分析了黑龙江省15°以上坡耕地现状,明确可退耕地情况,总结了国家最新退耕还林还草相关配套政策。并提出黑龙江省退耕还林还草面临的挑战与对策,以期为顺利开展退耕还林还草工作提供一定参考。     

我国退耕还林还草工程的现状及实施对策

对退耕还林还草工程及其试点工作的现状进行分析，提出进一步搞好退耕还林还草工程的实施对策，为进一步搞好退耕还林还草工作提供参考。     

退耕还林还草文化构建

退耕还林还草文化是弘扬生态文明理念之行,是繁荣新时期生态文化之需,是退耕还林还草工程建设之魂,是推动退耕还林还草高质量发展之要。文中在论述退耕还林还草文化建设重大理论与现实意义的基础上,提出了退耕还林还草文化建设的基本构想,包括退耕还林还草文化建设的基本思路、核心内容、基本特征、基本方法。退耕还林还草文化核心内容包括退耕还林还草物质文化、精神文化、制度文化、行为文化。退耕还林还草文化是一种复兴文化、智慧文化、和谐文化、科学文化,其建设的基本方法包括全面研究、系统归纳,深入挖掘、精心创作,吸收借鉴、博采众长,广泛传播、正面引导。深入研究退耕还林还草文化,对于深刻理解退耕还林还草这一生态文明建设史上的标志性工程具有重大意义。     

甘肃省退耕还林(草)工程及生态环境建设初探

退耕还林还草生态工程实施4年来，取得了一些成就，但技术、运作、认识等方面出现了许多需要探讨的问题。结合甘肃退耕还林还草的实际，阐述了甘肃的优势、应处理的各种关系、如何实施好退耕还林还草等问题。     

正确处理退耕还林还草工程中的两大关系

为了落实江泽民总书记提出的“再造山川秀美”的伟大号召，按照党中央、国务院的部署，从２０００年开始在长江上游、黄河上中游等地区认真开展了退耕还林还草试点工作。总体看，试点工作开展一年多来，中央关于“退耕还林（草），封山绿化，以粮代赈，个体承包”政策措施深受广大农民的拥护，试点工作进展顺利，并取得阶段性成果。实践证明，党中央、国务院关于退耕还林还草的决策和措施是完全正确的。为进一步做好退耕还林还草工作，本文从一年来退耕还林还草工程的实施过程中出现的问题入手，探讨当前在退耕还林还草工程实施中应注意处理…     

德国森林资源和环境监测技术体系及其借鉴

在全面回顾总结世界各国退耕还林还草概况的基础上 ,论述了中外退耕还林还草的三大不同特点 ,分析了国外退耕还林还草的历史实践对我国目前正在进行的退耕还林还草试点的四方面启示 ,以期推动我国退耕还林还草的健康发展。     

退耕还林还草高质量发展策略

退耕还林还草是世界著名生态工程,是"两山"理念的生动实践。文中在分析退耕还林还草面临的新形势的基础上,系统回答了什么是退耕还林还草高质量发展、为什么要推动退耕还林还草高质量发展、怎样推动退耕还林还草高质量发展,提出了退耕还林还草高质量发展的基本思路、发展目标、核心内容和政策对策。     

国家林业局原局长王志宝在中西部地区退耕还林还草工作座谈会上的讲话(摘要)

1　关于试点工作进展情况 　　国务院西部地区开发会议决定开展退耕还林还草试点工作以来，国家林业局、国家计委、财政部联合下发了《关于开展2000年长江上游、黄河上中游地区退耕还林(草)试点示范工作的通知》(林计发〔2000〕111号)，并印发了试点实施方案，对退耕还林还草工作进行了安排部署。二是经专家充分论证，编制下发了《长江上游、黄河上中游地区2000年退耕还林(草)试点示范科技支撑方案》。三是对 174个试点县的主管领导和技术骨干进行了政策、技术培训。四是组织专业队伍，对先行启动的四川、陕西、甘肃 3省 1999年退耕还林还草的面积和质量进行了核查，为兑现政策提供了依据。五是派出 6个调查组，分别对不同类型地区的试点工作进行了专题调研，掌握了各地退耕还林还草的试点工作情况。六是召开了由 17个省区市林业厅局长、主管处长和种苗站长参加的退耕还林还草工作座谈会，研究讨论了 7个退耕还林还草试点工作的管理办法、标准和规程。     

Farmer participation in reforestation incentive programs in Costa Rica

Reforestation programs are a common policy response among developing country governments in the tropics attempting to deal with environmental and economic problems caused by widespread deforestation. The objective of this paper is to examine participation by small-and medium-sized farms in two reforestation programs undertaken in recent years by one country, Costa Rica, which has been at the forefront of developing country environmental protection efforts. Analysis of a survey of 243 program participants and non-participants shows that farm households participating in reforestation programs had generally larger farm sizes, were dedicated to low labor-intensive, land-extensive agricultural activities, faced significant family on-farm labor constraints, were more heavily dependent on off-farm income sources, and had more extensive contact with local extension efforts. Logistic regression is employed to econometrically identify demographic, economic, and land use determinants of farm household participation in reforestation programs; the implications of these findings are analyzed. The limitations of reforestation programs, especially with regard to management factors and quality of reforested plots, are reviewed. Implications for improving the efficiency of reforestation programs and the merits of other policy alternatives are also discussed.     

多元统计分析方法在林业中应用及IBM-PC系列程序集编制的研究

从70年代开始,随着微机的普及、推广,多元统计分析方法及其他数值分析方法在各个领域得到越来越广泛的应用。这就产生了两种要求:一是系统总结多元统计分析方法理论和应用情况,评价它在林业中应用的可能及前途;二是要为微机配置一套通用程序,使林业工作者从繁重的计算工作中解放出来,使多元统计分析方法付诸实施,也有利于多元统计分析     

The importance of agroforestry education and training

Sustainable agriculture should involve the successful management of resources for agriculture to satisfy changing human needs, while maintaining or enhancing the quality of the environment and conserving natural resources. The rapid depletion of forest resources and agricultural sustainability — two major global concerns — could be impacted significantly through agroforestry practices. Widespread application of agroforestry concepts and techniques offers great potential for helping to alleviate critical shortages of fuelwood and contributing to sustainable farming systems. There is a vital need to broaden the knowledge base of the subject of agroforestry in order to provide a more substantive basis for effective teaching and training programs. In a typical university organization, it is fairly easy to see how interdisciplinary research teams can be brought together to work on agroforestry projects. But how do we structure the education and training programs? The purpose of this conference is to address these issues and to guide the further evolution and development of agroforestry.     

Willingness to pay function for two fuel treatments to reduce wildfire acreage burned: A scope test and comparison of White and Hispanic households

This research uses the Contingent Valuation Method to test whether willingness to pay increases for larger reductions in acres of forests burned by wildfires across the states of California, Florida and Montana. This is known as a test of scope, a measure of internal validity of the contingent valuation method (CVM). The scope test is conducted separately for White households and Hispanic households to determine if cultural differences influences whether the scope test is passed. The public program to reduce acres burned involved prescribed burning and a mechanical fuel reduction program. The results of CVM logit regressions show that the acreage reduction variable is statistically significant at the 1% level for the two proposed fuel reduction programs, and the two types of households. The positive sign of this variable means that the more acreage reduction proposed in the survey the more likely people would pay for the fuel reduction program. Because of the significance of the acreage reduction variable in the willingness to pay function, this function can be used to evaluate the incremental benefits of different forest fire management plans that reduce acres burned by wildfires. These benefits would be part of the justification for prescribed burning and mechanical fire fuel reduction programs to protect forests from wildfires.     

An interdisciplinary online certificate and masters program in agroforestry

Over the past two decades, the American education system has experienced profound challenges due to long-term and sustained declines in federal and state funding, coupled with rapid and innovative progress in the development of advanced educational technologies. Concurrently, employers are increasing their expectations and outputs from their employees and as a result, working professionals are seeking affordable opportunities to upgrade their skills for career advancement while maintaining full time job responsibilities. Responding to these challenges, both public and private educational institutions have developed innovative online courses and curricula creating fully accredited undergraduate and graduate degree programs often at lower cost than in campus-based degree programs. These courses and programs enable working professionals and other non-traditional learners to realize their aspirations for advanced training, and breach the traditional barrier for those disadvantaged by limited time or distance. Agroforestry, the intentional mixing of trees with crop and/or animal production systems to create economic, environmental, and social benefits, is gaining recognition as an integral component of multifunctional working landscapes. While gradually gaining attention, widespread agroforestry illiteracy remains and the need for a cadre of well trained professionals is essential to support its continued growth. Short courses and workshops are helpful, but professionals and landowners alike across the U.S., Canada and overseas are seeking more comprehensive graduate degree or certificate programs. A web-based, asynchronous M.S. degree and/or a graduate Certificate will help to fill this void. Presently, there are no comparable comprehensive graduate programs in agroforestry elsewhere in the U.S. To meet the current and future needs of the agroforestry profession, The Center for Agroforestry at the University of Missouri has created an online graduate certificate and master’s degree program in agroforestry. Initial student evaluation data reveals that online agroforestry courses compare favorably with face-to-face courses. This program will serve as a model for other institutions interested in developing online programs in agroforestry and related disciplines.     

基于表面建模技术的数控车床动态加工仿真模型研究

在充分考虑数控车床加工表面特征的基础上,对以往仿真模型的不足进行了分析,提出了基于螺旋曲面的加工表面模型。该模型充分考虑了数控程序中主轴转速和进给速率两个重要参数,并提出了数控车床动态加工过程仿真的时间驱动机制。     

美国林务局计划体系及其分析工具

本文介绍了美国农业部林务局(USDAFS,简称美国林务局)的林业计划体系及其计划分析工具,论述了美国林务局林业计划体系的组织形式和执行方式,特别是在制订不同层次的复杂的林业计划时所采用的民主、科学的管理手段,很值得我们学习与借鉴。     

Natural factors affecting wood structure

The structure and properties of wood are affected by genetic, environmental and anthropogenic factors acting during the formation of wood cells and tissue. In order to understand these factors and the way they interact, wood scientists face exciting and challenging problems in two areas of plant biology. Firstly, they need to understand the molecular basis for genetic programs which code for various fundamental processes of xylogenesis. The most promising area seems to lie in the identification of genetic programs for seasonal initiation and termination of cambial activity. Secondly, they need to understand the basic code, the mechanism of propagation and the transduction system of morphogenetic messages which provide information for structural differentiation of xylem in the plant. This paper discusses the various concepts concerning the contribution of auxin to the morphogenetic fields in which the information is specified without spatial, directional or time-limiting conditions. Received 2 January 2001     

Voluntary Certification Design Choices Influence Producer Participation,Stakeholder Acceptance,and Environmental Sustainability in Commodity Agriculture Sectors in Tropical Forest Landscapes

Voluntary certification programs are one type of intervention used to incentivize the agricultural commodity sector in tropical landscapes to reduce deforestation and improve sustainability. Cases of the Roundtable on Sustainable Palm Oil (RSPO) voluntary certification program in Indonesia and the Sustainable Agriculture Network (SAN), voluntary certification for cattle in Brazil, are used to contrast the role taken in two significantly different programs to render sustainability outcomes. While producers in both countries follow a similar path toward compliance with certification standards, only the RSPO program offers enticements for producers to participate in the intermediate stages of compliance by offering membership in its affiliated industry roundtable. Design choices about the core activities of a program (adoption, implementation, and enforcement and monitoring) that are ancillary to standards setting are found to be opportunities for providing benefits to both producers and civil society stakeholders without compromising the program’s rigor. A framework is proposed to understand voluntary certification programs as both creators and brokers of benefits between producers and other sustainability stakeholders, potentially providing an approach to simultaneously increase participation and maintain program rigor.     

Application of for the identification and management of hybrid poplar accessions

Molecular markers are a powerful tool with many potential applications in agriculture and forestry. In particular, can provide information on the relatedness of various clones or varieties that are difficult to distinguish morphologically, thus helping in the management of plant accessions and in breeding programs. The goal of this study is to genotype 15 clones used in the Prairie Farm Rehabilitation Administration (PFRA) breeding programs. Simple Sequence Repeat (SSR, or microsatellite markers) were selected for genotyping using the polymerase chain reaction (PCR). This type of marker is considered the method of choice due to their abundance, polymorphism and reliability compared to other types of . Sixteen previously isolated and characterized in aspen (Populus tremuloides) and other poplar species (Populus spp.) were initially tested. Nine markers were selected based on the “informativeness” and the quality of the amplification products. The nine markers were combined in groups of three to improve the efficiency of the genotyping technique. Using the nine markers, the average number of alleles per locus was 5.1. The expected and observed heterozygosity ranges were 0.32 to 0.80 and 0.13 to 0.92 respectively. The results also show that it is possible to produce a unique “DNA fingerprint” specific to each of the 15 hybrid poplar clones with the nine . In this study it was possible to show that two clones, P. ‘Melville’ and P. x ‘Walker’ used in Saskatchewan have similar DNA profiles with nine markers and a combined probability of identity of 2.23×10⁻⁶ suggesting that these clones are identical. This observation will prevent unnecessary duplication of the two accessions in breeding programs. This revised version was published online in August 2006 with corrections to the Cover Date.