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Digitally determining forest inventory units with an ecological classification system

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Science china(Technological Sciences) 2006年第z1期49卷 118-127页

作者： tang una, WANG Qingli, guofan shao, dai limin, WANG Shunzhong, LI Xiufen & XU Dong institute of Applied Ecology, chinese academy of Sciences, Shenyang 110016, china Graduate University of chinese academy of Sciences, beijing 100101, china Department of forestry and Natural resources, Purdue University, West Lafayette, IN 47907, USA institute of Applied Ecology Chinese Academy of Sciences

Management-level forest resource data in china were obtained with a combination of two forest inventories. However, inconsistencies in the spatial attributes of forest data vary between the two inventory types and between two inventories of the same type. The inconsistencies make it inconvenient for long-term forest management planning with digital technologies. Ecological Land Types (ELTs) and Ecological Land Type Phases (ELTPs) have been mapped in selected forestry regions in northeast china, where important forest industries are located. The boundaries of ELTs are determined by geomorphic conditions, which are quantified by Digital Elevation Models (DEM); ELTPs are classified by overlaying ELTs with forest vegetation data layers that are obtained with both remotely sensed and ground data. The ELTPs represent the divisions of land in terms of both natural and human-induced forest conditions, and therefore they are reliable units for forest inventories and management. This paper introduces a case study for digitally determining forest inventory units in Benxi City, Liaoning Province, northeast china. The general objective of the study was to explain how a compatible forest inventory system should be designed and why the compatible forest inventory system was significant to digital forestry in china.

关键词： forest inventory, ecological classification, ELT mapping, ELTP mapping, geographic information systems, forest management.

Practice and research Progress on Ecosystem Conservation in Transboundary Areas

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chinese Geographical Science 2016年第1期26卷 109-116页

作者： tang Lina GUI Liuming shao guofan WANG Luyan SHI Longyu Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences Department of forestry and Natural resources Purdue University

Many ecosystems extend across national or political boundaries. The consistent and effective protection of these ecosystems in transboundary areas(ETAs) is an important global research focus. Previous research on the protection of such areas can be categorized into seven themes: 1) ecological conservation of a single ETA; 2) investigation of the effects of a single conservation measure on a specific ETA; 3) determination of species-level effects due to ETA conservation; 4) comparison of the same protection measures between different ETAs; 5) introduction of a single conservation measure to a specific ETA; 6) understanding the relationship between conservation and sustainable development; and 7) generalization across multiple ETA conservation cases. The protection of ETAs involves various considerations, including funding support, demand and will for collaboration, community and public participation, historical and cultural factors, political backgrounds, uniqueness of biological resources, formulation of laws and regulations, founding of specialized administrative departments, non-governmental organizations, and fairness. Here, we briefly explain the research themes and considerations related to ETA conservation. The most important finding is that most major research themes do not focus on the challenges of ETA conservation. We use two nature reserves located between china and North Korea as examples to identify specific ways to improve ETA conservation on Changbai Mountains. The efficiency of ETA administration still remains low. The study of ETA conservation should focus on concrete regional information and aim to improve existing measures through the accumulation of experience.

关键词： ecosystem in transboundary area (ETA) intemational cooperation transboundary cooperation regional sustainable development terrestrial ecosystem

长江上游鲢幼鱼空间分布特征及其关键环境因子判别

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长江流域资源与环境 2023年第6期32卷 1220-1228页

作者：蒲艳杨浩田辉伍邓华堂倪文静魏念段辛斌刘绍平陈大庆西南大学生命科学学院淡水鱼类资源与生殖发育教育部重点实验室重庆400715 中国水产科学研究院长江水产研究所湖北武汉430223 西南大学水产学院渔业与水产生物技术实验室重庆400715 上海海洋大学水产与生命学院上海201306

鲢(Hypophthalmichthys molitrix)是长江重要的中上层经济鱼类,为了解长江上游鲢幼鱼空间分布变化与环境因子之间的关系。根据2019年9月至2020年1月在长江上游至三峡库区开展的渔业资源调查和水文环境数据,并利用广义可加模型(GAM)筛选... 详细信息

鲢(Hypophthalmichthys molitrix)是长江重要的中上层经济鱼类,为了解长江上游鲢幼鱼空间分布变化与环境因子之间的关系。根据2019年9月至2020年1月在长江上游至三峡库区开展的渔业资源调查和水文环境数据,并利用广义可加模型(GAM)筛选影响其分布特征的主要环境因子。结果显示,长江上游鲢幼鱼资源密度具有显著的空间分布差异,主要分布于三峡库区丰都江段;影响鲢幼鱼资源密度分布的主要环境因子为流速、浮游生物密度、离坝距离和水温,其中流速偏差解释率最大为57.7%。随着流速增大,鲢幼鱼资源密度整体呈现降低的趋势,集中分布于0.10~0.55 m/s流速范围内;浮游生物密度和离坝距离与鲢资源密度具有显著的线性关系,即随着浮游生物密度增加和距离大坝越远,其鲢幼鱼资源密度呈现上升趋势;随着水温的升高,鲢幼鱼资源密度整体呈现缓慢上升的趋势,集中分布在18℃~21.5℃水温范围内。本研究揭示了长江上游流速、浮游生物密度、离坝距离和水温变化对鲢幼鱼空间分布特征的影响。在长江十年禁渔背景下,应加强缓流生境库区和干支流汇合处的生境保护,为鲢种群资源量恢复构建重要栖息地。

关键词：鲢广义可加模型空间分布环境因子长江上游

基于居民用户调控潜力精细评估的台区侧灵活资源多目标日前优化调度

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供用电 2022年第9期39卷 42-50页

作者：张世帅陈毓春邵雪松张君之陈霄唐巍国网电力科学研究院北京100085 国网江苏省电力有限公司营销服务中心江苏南京210019 中国农业大学信息与电气工程学院北京100083 国网江苏省电力有限公司江苏南京210014

以空调和电热水器为代表的居民温控负荷和电动汽车是台区用户侧重要的灵活可调资源,具有较大的调控潜力。由于居民负荷的参数不尽相同,配电调度中心难以直接准确评估其调控响应潜力,导致调度计划与实际调度要求存在较大差异。针对上述问... 详细信息

以空调和电热水器为代表的居民温控负荷和电动汽车是台区用户侧重要的灵活可调资源,具有较大的调控潜力。由于居民负荷的参数不尽相同,配电调度中心难以直接准确评估其调控响应潜力,导致调度计划与实际调度要求存在较大差异。针对上述问题,构建了台区侧灵活资源协同调度框架,并建立各温控负荷和电动汽车聚合模型;提出了基于物理特征量分类聚合的灵活资源调控潜力精细评估方法;在此基础上,以电网削峰需求偏差最小和电网收益最大为目标,兼顾调峰目标和光伏出力的不确定性,建立了台区侧温控负荷和电动汽车灵活资源模糊机会约束多目标日前优化调度模型,并通过模糊约束条件清晰等价类转换实现模型求解。仿真结果表明该方法通过选择合适的权重系数可以实现电网调峰需求和经济利益的平衡,模糊机会约束规划置信水平取0.90时结果最优。

关键词：灵活资源功率聚合日前调度模糊机会约束规划配电台区

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云南省古茶树资源调查与分析

植物遗传资源学报 2020年第2期21卷 296-307页

作者：蒋会兵唐一春陈林波王平盛蔡新虞富莲杨柳霞王兴华李崇兴江鸿键王本忠段学良李静何月波王东李少峰卜保国云南省农业科学院茶叶研究所勐海666201 云南农业大学龙润普洱茶学院昆明650201 中国农业科学院茶叶研究所杭州310008 云南省普洱市茶树良种场普洱665000 云南省临沧市茶叶科学研究所临沧677000 云南省临沧市发展生物办公室临沧677000 云南省文山州农业农村局文山663000 云南省保山市农业农村局保山678000 云南省西双版纳州农业农村局勐海666100 云南省红河州农业农村局蒙自661100 云南省德宏州农业农村局芒市678400 云南省大理州农业农村局大理671000 云南省楚雄州农业农村局楚雄675000

为更好地保护和开发利用古茶树资源,2010-2017年对云南省12个地区58个县/市的古茶树资源进行了全面普查,依据《Flora of china》英文修订版分类确立了古茶树资源物种名录,建立初步的古茶树资源数据信息库。以此为基础,利用地理信息系统... 详细信息

为更好地保护和开发利用古茶树资源,2010-2017年对云南省12个地区58个县/市的古茶树资源进行了全面普查,依据《Flora of china》英文修订版分类确立了古茶树资源物种名录,建立初步的古茶树资源数据信息库。以此为基础,利用地理信息系统和统计学分析了云南古茶树资源种类组成、地理分布特征、生境类型及形态多样性。结果表明:云南古茶树种类多,调查共获得古茶树资源分布点474个,记录样本植株2570份,隶属7种6变种;古茶树资源分布广而不均,主要分布于滇西、滇南、滇东南及滇中哀牢山山脉,滇东南是古茶树物种多样性的分布中心,滇西是特有种的分化中心,云南古茶树资源的地理分布可能存在滇西-大理茶(Camellia taliensis(***.)Melch.)、滇南-普洱茶(*** ***(***.)Kitam.)和滇东南-厚轴茶(*** ***)3个现有分布中心;古茶树资源生境复杂多样,可大致分为原生林、次生林和高山旱地等3类,不同生境分布的古茶树种类及其生长状况有差异;古茶树资源具有丰富的形态多样性,其描述型性状多样性指数为0.58~1.48,数值型性状变异系数为4.37%~51.03%,总体上营养器官的变异性高于花部器官。本工作为进一步探讨云南地区古茶树资源的系统演化、多样性保护及合理利用提供了重要的本底资料。此外,根据古茶树资源现状,初步提出了一些保护利用建议。

关键词：古茶树资源调查地理分布生境形态多样性

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二维材料最新研究进展

物理化学学报 2021年第12期37卷 1-151页

作者：常诚陈伟陈也陈永华陈雨丁峰樊春海范红金范战西龚成宫勇吉何其远洪勋胡晟胡伟达黄维黄元季威李德慧李连忠李强林立凌崇益刘鸣华刘楠刘庄 Kian Ping Loh 马建民缪峰彭海琳邵明飞宋礼苏邵孙硕谭超良唐智勇王定胜王欢王金兰王欣王欣然 Andrew T.S.Wee 魏钟鸣吴宇恩吴忠帅熊杰熊启华徐伟高尹鹏曾海波曾志远翟天佑张晗张辉张其春张铁锐张翔赵立东赵美廷赵伟杰赵运宣周凯歌周兴周喻朱宏伟张华刘忠范 institute of Science and Technology Austria Am Campus 13400 KlosterneuburgAustria Department of Chemistry National University of Singapore3 Science Drive 3117543Singapore Department of Chemistry The Chinese University of Hong KongShatinNew TerritoriesHong KongChina Key Laboratory of Flexible Electronics and institute of Advanced Materials Nanjing Tech UniversityNanjing 211816China School of Life Sciences Shanghai UniversityShanghai 200444China Centre for Multidimensional Carbon Materials Institute for Basic ScienceUlsan 44919Korea School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore Department of Chemistry City University of Hong KongKowloonHong KongChina Department of Electrical and Computer Engineering and Quantum Technology Center University of MarylandCollege ParkMaryland 20742USA School of Materials Science and Engineering Beihang UniversityBeijing 100191China Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Center of Advanced Nanocatalysis(CAN) Hefei National Laboratory for Physical Sciences at the MicroscaleDepartment of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China College of Chemistry and Chemical Engineering State Key Laboratory of Physical Chemistry of Solid SurfacesCollaborative Innovation Center of Chemistry for Energy Materials(iChEM)Xiamen UniversityXiamen361005Fujian ProvinceChina State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China Advanced research institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing100081China beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of PhysicsRenmin University of ChinaBeijing 100872China School of Optical and Electronic information Wuhan National Laboratory

research on two-dimensional(2D) materials has been explosively increasing in last seventeen years in varying subjects including condensed matter physics, electronic engineering, materials science, and chemistry since the mechanical exfoliation of graphene in 2004. Starting from graphene, 2D materials now have become a big family with numerous members and diverse categories. The unique structural features and physicochemical properties of 2D materials make them one class of the most appealing candidates for a wide range of potential applications. In particular, we have seen some major breakthroughs made in the field of 2D materials in last five years not only in developing novel synthetic methods and exploring new structures/properties but also in identifying innovative applications and pushing forward commercialisation. In this review, we provide a critical summary on the recent progress made in the field of 2D materials with a particular focus on last five years. After a brief backgroundintroduction, we first discuss the major synthetic methods for 2D materials, including the mechanical exfoliation, liquid exfoliation, vapor phase deposition, and wet-chemical synthesis as well as phase engineering of 2D materials belonging to the field of phase engineering of nanomaterials(PEN). We then introduce the superconducting/optical/magnetic properties and chirality of 2D materials along with newly emerging magic angle 2D superlattices. Following that, the promising applications of 2D materials in electronics, optoelectronics, catalysis, energy storage, solar cells, biomedicine, sensors, environments, etc. are described sequentially. Thereafter, we present the theoretic calculations and simulations of 2D materials. Finally, after concluding the current progress, we provide some personal discussions on the existing challenges and future outlooks in this rapidly developing field.

关键词： Two-dimensional materials Transition metal dichalcogenides Phase engineering of nanomaterials Electronics Optoelectronics Catalysis Energy storage and conversion