检索结果-南通市图书馆

Silvicultural alternatives to conventional even-aged forest man-agement-what limits global adoption?

在线全文

学校读者我要写书评

暂无评论

Forest Ecosystems 2015年第2期2卷 123-138页

作者： Klaus J Puettmann Scott McG Wilson Susan C Baker Pablo J Donoso Lars Dr?ssler Girma Amente Brian D Harvey Thomas Knoke yuanchang lu Susanna Nocentini Francis E Putz Toshiya Yoshida Jürgen Bauhus Department of Forest Ecosystems and Society Oregon State University Consultant Forester and Forest Ecologist School ofBiological Sciences University of Tasmania Department of Forests and Society Faculty of Forest Sciences and Natural Resources Universidad Austral de Chile Southern Swedish Forest Research Centre Swedish Agricultural University Haramaya University Institut de recherche sur les forêts Université du Québec en Abitibi-Témiscamingue 445 Boulevard de l’Université Institute of Forest Management TUMSchool of Life Sciences Weihenstephan Technische Universit?t München Department of Forest Management and Statistics IFRIT Chinese Academy of Forestry Department of Agricultural Food and Forestry Systems University of Florence Department of Biology University of Florida Uryu Experimental Forest Field Science Center for Northern Biosphere Hokkaido University Chair of Silviculture Faculty of Environment and Natural Resources University of FreiburgTennenbacherstr

Background： The development of forestry as a scientific and management discipline over the last two centuries has mainly emphasized intensive management operations focused on increased commodity production, mostly wood. This conventionar＇ forest management approach has typically favored production of even-aged, single-species stands. While alternative management regimes have generally received less attention, this has been changing over the last three decades, especially in countries with developed economies. Reasons for this change include a combination of new information and concerns about the ecological consequences of intensive forestry practices and a willingness on the part of many forest owners and society to embrace a wider set of management objectives. Alternative silvicultural approaches are characterized by a set of fundamental principles, including avoidance of clearcutting, an emphasis on structural diversity and small-scale variability, deployment of mixed species with natural regeneration, and avoidance of intensive site-preparation methods. Methods： Our compilation of the authors＇ experiences and perspectives from various parts of the world aims to initiate a larger discussion concerning the constraints to and the potential of adopting alternative silvicultural practices. Results： The results suggest that a wider adoption of alternative silvicultural practices is currently hindered by a suite of ecological, economic, logistical, informational, cultural, and historical constraints. Individual contexts display their own unique combinations and relative significance of these constraints, and accordingly, targeted efforts, such as regulations and incentives, may help to overcome specific challenges. Conclusions： In a broader context, we propose that less emphases on strict applications of principles and on stand structures might provide additional flexibility and facilitate the adoption of alternative silvicultural regimes in a broader set of circumstances. At the same time, the acceptance of alternat

关键词： Natural Regeneration Forest Owner Stand Structure Commodity Production Private Landowner

Trees as hotspots:Using forests,trees,and agroforestry to foster diverse sustainable landscapes

在线全文

学校读者我要写书评

暂无评论

Circular Agricultural Systems 2022年第1期2卷 30-37页

作者： Vincent Gitz Jianchu Xu yuanchang lu Elaine Springgay Illias Animon Razan Khalifa Al Mubarak Robert Nasi Tony Simons Ranjit Barthakur Ren Wang Jianrong Su Fergus Sinclair Eduardo Somarriba Dossa G.O.Gbadamassi Ramni Jamnadass Christopher JKettle Dengpan Bu Anja Gassner Yves Laumonier Mi Zhou Himlal Baral Fangyuan Hua Peter AMinang Yufu Guo Michael Allen Brady Yanxia Li Peter Mortimer Bin Yang Heng Gui Fiona Worthy Deli Zhai Huafang Chen Huili Li Yufang Su Alexandre Meybeck Fabio Ricci CIFOR-ICRAF Bogor 16115Indonesia Center for Mountain Futures Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China CIFOR-ICRAF China Program World AgroforestryKunming 650201China State Key Laboratory of Animal Nutrition Institute of Animal SciencesChinese Academy of Agricultural SciencesBeijing 100081China Research Institute of Forest Resource Information Techniques Chinese Academy of ForestryBeijing 100091China Food and Agriculture Organization of the United Nations(FAO) Rome 00153Italy Food and Agriculture Organization of the United Nations(FAO) Bangkok 10200Thailand Mohamed bin Zayed Species Conservation Fund Abu Dhabi 131112United Arab Emirates Balipara Foundation GuwahatiAssam 781024India China National Gene Bank Shenzhen 518083China Research Institute of Resource Insects Chinese Academy of ForestryKunming 650233China World Agroforestry Centre(ICRAF) United Nations AvenueGigiriP.O.Box 30677-00100NairobiKenya CATIE Turrialba 30501Costa Rica Xishuangbanna Tropical Botanical Garden Chinese Academy of SciencesMengla 666303China Bioversity International Rome 00153Italy Global Landscapes Forum CIFOR gmbHCharles-de-Gaulle-Straße 553113 BonnGermany Institute of American and Oceania Study Chinese Academy of International Trade and Economic CooperationMinistry of CommerceBeijingChina Institute of Ecology Peking UniversityBeijing 100871China National Forestry and Grassland Administration Beijing 100714China International Network for Bamboo and Rattan(INBAR) Beijing 100102China Yunnan University Kunming 650500China Editorial Office of Biological Science Institute of BotanyChinese Academy SciencesBeijing 100093China

Forests,trees,and agroforestry(FTA)are ecosystem hotspots.They exemplify the contributions of biodiversity to sustainable and resilient landscapes,green circular economy and to sustainable agriculture and food systems for healthy diets.However,most research on these topics have been performed separately and lack comparison.The International FTA-Kunming Conference'Forests,trees and agroforestry for diverse sustainable landscapes'22nd–24th June 2021,focused on these contributions,brought together scientists NGOs,and policy makers to further the understanding of tree diversity;provided a communication platform for scientists to share their research results;evaluated the role of tree diversity in agroecology and circular agriculture;assessed benefits of landscape restoration;and explored applied research in mountain ecosystems and food security.The goals were to gather evidence that ground the design of solutions that can contribute to the implementation of the post 2020 Global Biodiversity Framework and towards the UN Food Systems Summit,and the overall implementation of the SDGs.This paper summarizes the outcomes of the international FTA Conference in Kunming 2021 and points out the highlights of research involved in six major themes.

关键词： landscape sustainable diverse

Variety regulation research of the Anthraquinone in San Cheng Qi Tang compound prescribe compatibility of medicines

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中医药学刊 2005年第5期23卷 869-871页

作者： SUNZhao-shu ZHANGZhen-qiu yuanchang-lu LiaoningUniversityofTraditionalChineseMedicine 110032Shenyang

The purpose is to research compound prescribe compatibility of medicines have some influence on anthraquinone which is the gentleman medicine CRC’s valid composition dissolution rate in San Cheng Qi Tang.The method:Adopting respectively RP-HPLC and colorimetric method,measure the content of liberation3-methylchrysazin and 3-methylchrysazin and combined 3-methylchrysazin and 3-methylchrysazin total liberation anthraquinone and total combined anthraquinone in the different decoction water liquid coming from single CRC the different decoction and compatibility of medicines method of San Cheng Qi Tang.The result: Compared with CRC single flavor decoction water,liberation anthraquinone and combined anthraquinone content show differently in the most decoction water liquid,Combined 3-methylchrysazin and combined anthraquinone content in decoction prescribe as follows in proper order decrease:Da Cheng Qi Tang > Xiao San Cheng Qi Tang > Tiao Wei Cheng Qi Tang.The conclusion :Because CRC mate with different medicine material .different decoction method,liberation anthraquinone and combined anthraquinone content in San Cheng Qi Tang change.The combined 3-methylchrysazin and combined anthraquinon content variety order in accordance with its decanta bottom function.

关键词：蒽醌中药汤剂中医药疗法含量检测三承气汤化学成分

亚热带森林土壤氮磷钾和有机质的空间格局及其对森林经营的启示

在线全文

学校读者我要写书评

暂无评论

Journal of Resources and Ecology 2022年第3期13卷 417-427页

作者：韩丽丽陆元昌马武孟京辉北京林业大学国家林业和草原局森林经营工程技术研究中心北京100083 中国林业科学研究院资源信息研究所北京100091 普渡大学林业与自然资源系美国印第安纳州西拉斐特47906

土壤氮磷钾和土壤有机质明显影响森林生长。但是,这些土壤特性具有空间异质性,这使得进行可持续森林经营变得更加复杂。因此,必须深入了解土壤氮磷钾和有机质的空间分布及其变异状况。在本研究中,我们在中国广西壮族自治区西南部的热带... 详细信息

土壤氮磷钾和土壤有机质明显影响森林生长。但是,这些土壤特性具有空间异质性,这使得进行可持续森林经营变得更加复杂。因此,必须深入了解土壤氮磷钾和有机质的空间分布及其变异状况。在本研究中,我们在中国广西壮族自治区西南部的热带林业实验中心,布设了181个样点并进行了采样,应用地统计学方法研究了土壤中氮磷钾和有机质的空间变异性。块金值与基台值的比值表明土壤中氮具有很强的空间依赖性,主要受内在因素影响(如土壤质地、母质、植被类型和地形),而土壤中有机质、磷钾具有中等的空间依赖性,受内在因素和外在因素(如栽培技术、施肥和种植模式)共同影响。在土壤中氮磷钾和有机质的空间变异性的基础上,本研究采用普通克里格方法进行空间插值,制作了土壤氮磷钾和有机质空间分布图。模型验证表明,土壤性质空间分布图能够可靠地指导森林经营活动。

关键词：土壤性质空间分布地统计普通克里格空间插值

Study on Transpiration and Stomatal Conductance Characteristics of C3 and C4 Plant

在线全文

学校读者我要写书评

暂无评论

Journal of Northeast Agricultural University(English Edition) 2009年第4期16卷 1-8页

作者： MENG Jinghui lu yuanchang Ronald Kohne LIU Gang Resource and Information Institute Chinese Academy of Forestry Beijing 100096 China Faulty of Forest Sciences and Ecology Universitity Goettingen Goettingen 37077 Germany Department of Crop Sciences-Tropical Agronomy Goettingen University Goettingen 37077 Germany College of Horticulture and Forestry Science Huazhong Agricultural University Wuhan 4300702 China

The transpiration experiment was done under greenhouse conditions with a C3 plant sweet pepper （Capsicum annuum Linn.） and two C4 plants, sorghum （Sorghum bicolor L.Moench） and maize （Zea mays Linn.）. Three species were irrigated with three different water treatment levels of 100%, 66% and 33% which gave a comparison of tolerance and adaptation to irrigation and two different levels of water stress. The measurements of transpiration rate and stomatal conductance were done between 8.00 a.m. and 16.00 p.m. with measurements about each 1.5 h with an infrared gas analyzer. The results showed that Z. mays probably due to a higher leaf area had very low values and was significantly different （LSD pairwise comparison） from C. annuum and S. bicolor. The hypotheses that C4 plants and C3 plants have different transpiration rates and stomatal conductance could not be shown with the results. However, the hypotheses that for the same species, the highest values in transpiration rate and stomatal conductance were with the 100% irrigation treatment and the lowest values were with the 33% irrigation treatment could be accepted due to the results of this trial.

关键词： transpiration rate stomatal conductance water stress

近30年西双版纳热带雨林群落冠层组成与结构的动态变化

在线全文

学校读者我要写书评

暂无评论

西北农林科技大学学报（自然科学版） 2023年第10期51卷 80-88,96页

作者：李建伟杜凡陆元昌杨健明刘瑞党雪芳石明西南林业大学林学院云南昆明650224 中国林业科学研究院资源信息研究所北京100091

【目的】研究1993—2021年西双版纳原始热带雨林在自然状态下的生长变化规律,为热带雨林的保护和恢复重建提供科学依据。【方法】为了解原始热带雨林的自然演变情况,对5块共1.25 hm2的望天树群落(Parashorea chinensis)样地开展了近30... 详细信息

【目的】研究1993—2021年西双版纳原始热带雨林在自然状态下的生长变化规律,为热带雨林的保护和恢复重建提供科学依据。【方法】为了解原始热带雨林的自然演变情况,对5块共1.25 hm2的望天树群落(Parashorea chinensis)样地开展了近30年的监测,从乔木层树种数量、树种多样性指数、个体数量、径级结构以及主要树种和偶见种等的变化分析群落演变。【结果】①1993年初测时5块样地记录乔木层树种183种,隶属于48科116属,到2021年乔木层树种减少到177种,隶属于43科112属,其间有28个种退出乔木层,22个种新进入乔木层,退出及新进入的乔木多为偶见种;群落的丰富度指数和Simpson指数均呈小幅下降,年均减少率分别为0.12%和0.08%。②28年来,5块样地乔木树种个体由1963株减少到1779株,累计死亡699株,年均死亡率1.27%;累计进界515株,年均进界率0.94%。死亡乔木集中于小径级(5 cm≤胸径(DBH)<15 cm)个体,计485株,占总死亡株数的69.38%;大径级(DBH≥45 cm)个体死亡最少,计16株,占2.29%。初测时5块样地中有21个主要树种,计1189株;2021年减少至18个主要树种,计1155株,其间进界324株,死亡353株,年均进界率及年均死亡率分别为0.94%和1.03%;望天树及假海桐等5个主要树种的种群数量在增加,毒鼠子和钝叶桂等15个主要树种的种群数量在减少,金钩花和阔叶蒲桃的种群数量保持不变。③群落的径级结构未发生明显变化,均以小径级的个体数量最多,随着胸径的增大个体数量逐渐减少,呈倒“J”型分布。主要树种个体数量波动随径级增大在减小,而偶见种各径级个体数量波动均较大,且无论在哪个径级,主要树种的径级结构都比偶见种径级结构变化小。【结论】虽然望天树群落各项指标均有一定变化,但波动不明显,群落外貌特征基本保持不变,整体发展较为稳定,群落接近顶极群落状态。

关键词：望天树林乔木层树种种群变化动态群落结构西双版纳

在线全文

学校读者我要写书评

暂无评论

森林改善空气环境质量功能监测与评价研究

生态环境学报 2015年第1期24卷 84-89页

作者：邓成张守攻陆元昌中国林业科学研究院北京100091 广西林业勘测设计院广西南宁530028

为全面了解森林内部属性与森林改善空气环境功能之间的内在关系与规律,以及不同森林在改善空气环境质量方面的能力强弱,以中国林业科学研究院热带林业试验中心为研究对象,于2014年7─8月按照2 km×2 km网格间距进行系统抽样,设置51个样... 详细信息

为全面了解森林内部属性与森林改善空气环境功能之间的内在关系与规律,以及不同森林在改善空气环境质量方面的能力强弱,以中国林业科学研究院热带林业试验中心为研究对象,于2014年7─8月按照2 km×2 km网格间距进行系统抽样,设置51个样地对森林空气温度、湿度、负氧离子含量等空气环境状况指标及林分特征因子进行了监测,并对林分类型、发展阶段、郁闭度等林分因子与森林空气温度、湿度、负氧离子含量之间的关系进行了分析。采用温湿指数、安培空气质量评价系数、森林空气负氧离子评价模型对不同类型森林的空气环境质量进行了评价。结果表明：1）森林改善空气环境质量功能主要与其林分类型、发展阶段、林分郁闭度有关;2）在调节空气温湿度,改善空气环境舒适度方面,针叶混交林最强,然后依次为针阔混交林、阔叶混交林、针叶纯林、阔叶纯林、灌木林,以未成林最弱。在吸附污染物、净化空气方面,针阔混交林最强,然后依次为阔叶混交林、阔叶纯林、针叶混交林、针叶纯林、灌木林,以未成林最弱;3）不同发展阶段的林分在改善空气环境舒适度方面的差异不明显,但随着林分发展阶段的深入,森林的结构越来越复杂,森林净化空气的能力也逐渐增强;4）森林在调节空气温湿度,改善空气环境舒适度等方面的功能随郁闭度的增加而增强,当郁闭度大于0.4时,森林改善空气环境舒适度的功能显著增强。郁闭度在0.4-0.7之间的林分净化空气的功能较强,尤以郁闭度为0.5时最强,当林分郁闭度低于0.4或高于0.7以后,林分净化空气的功能均有所降低;5）总体来说混交林改善空气环境质量的功能要显著强于纯林。研究结果对于经营单位如何通过林分状态的调控来增强森林的空气环境改善功能具有重要指导意义。

关键词：森林空气环境森林功能监测森林功能评价温湿指数空气负氧离子

在线全文

学校读者我要写书评

暂无评论

经营单位级的森林多功能监测体系研究

西北农林科技大学学报（自然科学版） 2016年第7期44卷 131-137页

作者：邓成张守攻陆元昌唐学君广西林业勘测设计院广西南宁530028 中国林业科学研究院北京100091 国家林业局华东林业调查规划设计院浙江杭州310019

【目的】研究经营单位级的森林多功能监测体系,为森林经营单位及时掌握多功能森林的生长发育状态、内部结构特征、更新演替规律及其与所处环境间的相互关系提供有效手段,进而为其森林多功能经营提供数据支撑和理论指导。【方法】以中国... 详细信息

【目的】研究经营单位级的森林多功能监测体系,为森林经营单位及时掌握多功能森林的生长发育状态、内部结构特征、更新演替规律及其与所处环境间的相互关系提供有效手段,进而为其森林多功能经营提供数据支撑和理论指导。【方法】以中国林业科学研究院热带林业试验中心森林为研究对象,从抽样体系设计、样地布设方法、调查因子设置及观测指标数据采集等方面对森林多功能监测技术进行系统介绍和实践操作。【结果】基于1km×1km网格抽样框架,通过二重系统抽样,采用群状圆形样地方式,布设一重样地和二重样地,建立了经营单位级的森林多功能监测体系。实践操作结果表明,采用该监测体系调查一个样地所需费用与我国森林资源连续清查所需费用相当,但工作量仅约为后者的1/3,其中对热带林业实验中心森林蓄积量的抽样精度为94.97%,说明抽样效率较高。【结论】建立的经营单位级森林标多功能该监测体系实用性强,监测效率高,对森林经营单位开展森林多功能经营及森林多功能综合监测具有指导意义。

关键词：经营单位级森林多功能多功能监测体系

利用QAR和DEM的机载气象雷达地杂波仿真方法

在线全文

学校读者我要写书评

暂无评论

数据采集与处理 2017年第4期32卷 785-791页

作者：张金玉秦娟卢晓光钟元昌天津理工大学电气电子工程学院薄膜电子与通信器件重点实验室天津300384 中国民航大学智能信号与图像处理天津市重点实验室天津300300

地杂波是降低机载气象雷达性能的一个关键因素。利用数字高程模型(Digital elevation model,DEM)精确计算不同地形的电磁散射时,本文提出了将经纬度变化量转换成距离变化量的方法,简化计算,并修正了俯角和擦地角计算。然后根据气象雷达... 详细信息

地杂波是降低机载气象雷达性能的一个关键因素。利用数字高程模型(Digital elevation model,DEM)精确计算不同地形的电磁散射时,本文提出了将经纬度变化量转换成距离变化量的方法,简化计算,并修正了俯角和擦地角计算。然后根据气象雷达方程建模地杂波,按照WXR-2100的实际参数设置雷达参数,结合快速存取记录器(Quick access recorder,QAR)反演的航班飞行参数,分别高保真地仿真了起飞和巡航两个阶段机载气象雷达不同工作模式下的杂波图,反映了实际的运行情况,最后建立了杂波图数据库。

关键词：机载气象雷达地杂波仿真数字高程模型快速存取记录器坐标转换