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基于最小尺度的浙江省毛竹生物量精确估算 被引量:8
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作者 周国模 刘恩斌 +2 位作者 施拥军 刘安兴 周宇峰 《林业科学》 EI CAS CSCD 北大核心 2011年第1期1-5,共5页
以浙江省为例,提出基于最小尺度的区域生物量估算新方法,包含3方面内容:1)利用二元Weibull生存函数推导二元Weibull分布函数,并用二元Weibull分布函数估算浙江省各径阶、各龄级毛竹的总株数;2)利用已有毛竹胸径、年龄二元单株生物量模型... 以浙江省为例,提出基于最小尺度的区域生物量估算新方法,包含3方面内容:1)利用二元Weibull生存函数推导二元Weibull分布函数,并用二元Weibull分布函数估算浙江省各径阶、各龄级毛竹的总株数;2)利用已有毛竹胸径、年龄二元单株生物量模型f(D,A),计算各径阶、各龄级毛竹的生物量;3)利用公式MT=∑mi=5∑nj=1kijf(Di,Aj)实现区域尺度生物量的精确估算。用该方法估算得浙江省毛竹总生物量为1.4716×1010kg。 展开更多
关键词 毛竹 二元Weibull分布函数 区域尺度生物量估算 浙江省
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森林生物量模型综述 被引量:101
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作者 王维枫 雷渊才 +1 位作者 王雪峰 赵浩彦 《西北林学院学报》 CSCD 北大核心 2008年第2期58-63,共6页
根据研究对象尺度不同将生物量模型分为单木生物量模型和大尺度森林生物量模型。分别介绍了这两类生物量模型的历史和现状,简要概括了生物量模型特点和存在的一些问题,并且对未来的发展趋势做了预测。
关键词 森林生物 单木生物量模型 尺度森林生物量模型 材积源生物量模型 遥感
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城市生物多样性分布格局研究进展 被引量:113
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作者 毛齐正 马克明 +5 位作者 邬建国 唐荣莉 张育新 罗上华 宝乐 蔡小虎 《生态学报》 CAS CSCD 北大核心 2013年第4期1051-1064,共14页
城市生物多样性分布格局由自然生态环境和城市化过程所决定;其动态和机理与自然生态系统迥然不同。城市生物多样性为城市生态系统提供了诸多生态系统功能和服务,对改善城市环境、维持城市可持续发展有着重要的意义和作用。城市化过程深... 城市生物多样性分布格局由自然生态环境和城市化过程所决定;其动态和机理与自然生态系统迥然不同。城市生物多样性为城市生态系统提供了诸多生态系统功能和服务,对改善城市环境、维持城市可持续发展有着重要的意义和作用。城市化过程深刻改变了城市的生物多样性分布格局,导致了诸如本地物种多样性降低、外来物种多样性增加、物种同质化等一系列问题。近年来,城市生物多样性受到学界高度关注,大量研究结果既回答了一些关键性问题,又提出了诸多新的论题和挑战。分析了当前城市生物多样性分布格局研究的若干热点问题,总结了影响城市生物多样性格局的主要因素,探讨了城市生物多样性格局研究方法的关键问题,指出了未来城市生物多样性研究的发展方向,特别强调了城市生物多样性的生态系统功能研究在未来城市生物多样性研究中的重要地位。 展开更多
关键词 城市生态学 城市生物多样性 生物多样性格局和尺度 城市生态系统功能和服务
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在利基市场中寻求生存之道
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《生物医药世界》 2002年第2期39-41,共3页
关键词 生物尺度公司 利基市场 整形外科产品 企业发展 产品 技术
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单细胞尺度下的微生物学研究:意义与方法 被引量:11
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作者 陈子熙 陈磊 张卫文 《微生物学报》 CAS CSCD 北大核心 2017年第6期920-931,共12页
最近研究表明,即便是处于同一种群中的微生物细胞,在基因转录和翻译、蛋白活性、以及代谢物丰度等多个水平都可能存在显著差异,说明微生物细胞间存在着多个层次上的异质性;同时,传统微生物学研究方法需要将所研究的微生物对象在实验室... 最近研究表明,即便是处于同一种群中的微生物细胞,在基因转录和翻译、蛋白活性、以及代谢物丰度等多个水平都可能存在显著差异,说明微生物细胞间存在着多个层次上的异质性;同时,传统微生物学研究方法需要将所研究的微生物对象在实验室实现再次培养,然后对纯培养的微生物种群进行研究,这样往往造成实验室的研究结果无法真实地反映微生物细胞在自然界中的原始状态,急需发展新的原位研究手段;此外,自然界中的微生物目前只有极少部分可以在实验室中进行培养,仍有大量微生物无法通过传统方法进行发掘和研究。单细胞尺度微生物学为解决这些微生物学研究中的重要挑战提供了一种新的策略和技术思路,有望帮助我们更为直观、深入地了解每个细胞内部的状态,以及其在自然界的生理生态功能。本文对单细胞尺度微生物学研究的意义以及当前单细胞尺度微生物学的研究方法,特别是新兴的微生物单细胞组学方法进行了介绍。 展开更多
关键词 单细胞尺度生物 异质性 不可培养微生物 单细胞基因组学 单细胞转录组学
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Responses of Tree Species to Climate Warming at Different Spatial Scales 被引量:2
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作者 LIANG Yu HE Hong S LEWIS Bernard L 《Chinese Geographical Science》 SCIE CSCD 2011年第4期427-436,共10页
Tree species respond to climate change at multiple scales,such as species physiological response at fine scale and species distribution (quantified by percent area) at broader spatial scale.At a given spatial scale,sp... Tree species respond to climate change at multiple scales,such as species physiological response at fine scale and species distribution (quantified by percent area) at broader spatial scale.At a given spatial scale,species physiological response and distribution can be correlated positively or negatively.The consistency of such correlation relationships at different spatial scales determines whether species responses derived from local scales can be extrapo-lated to broader spatial scales.In this study,we used a coupled modeling approach that coupled a plot-level ecosystem process model (LINKAGES) with a spatially explicit landscape model (LANDIS).We investigated species physio-logical responses and distribution responses to climate warming at the local,zonal and landscape scales respectively,and examined how species physiological response and distribution correlated at each corresponding scale and whether the correlations were consistent among these scales.The results indicate that for zonal and warming-sensitive species,the correlations between species physiological response and distribution are consistent at these spatial scales,and therefore the research results of vegetation response to climate warming at the local scale can be extrapolated to the zonal and landscape scales.By contrast,for zonal and warming-insensitive species the correlations among different spatial scales are consistent at some spatial scales but at other scales.The results also suggest that the results of azonal species at the local scale near their distribution boundaries can not be extrapolated simply to broader scales due to stronger responses to climate warming in those boundary regions. 展开更多
关键词 climate warming vegetation response local scale zonal scale landscape scale LANDIS Changbai Mountains
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气候变化与生物多样性之间的复杂关系和反馈机制 被引量:12
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作者 井新 蒋胜竞 +2 位作者 刘慧颖 李昱 贺金生 《生物多样性》 CAS CSCD 北大核心 2022年第10期289-307,共19页
气候变化与生物多样性丧失是人类社会正在经历的两大变化。气候变化影响生物多样性的方方面面,是导致生物多样性丧失的一个主要驱动因子;反过来,生物多样性丧失会加剧气候变化。因此,阻止甚至扭转气候变化和生物多样性丧失是当前人类社... 气候变化与生物多样性丧失是人类社会正在经历的两大变化。气候变化影响生物多样性的方方面面,是导致生物多样性丧失的一个主要驱动因子;反过来,生物多样性丧失会加剧气候变化。因此,阻止甚至扭转气候变化和生物多样性丧失是当前人类社会亟需解决的全球性问题,但我们对气候变化与生物多样性之间的复杂关系和反馈机制尚缺乏清晰认识。本文总结了近年气候变化与生物多样性变化的研究进展,重点概述了不同组织层次、空间尺度和维度的生物多样性对气候变化的响应和反馈等相关领域的研究进展和存在的主要问题。结果发现多数研究关注气候变化对生物多样性的直接影响,涉及到生物多样性的不同组织层次、维度和营养级,但针对气候变化间接影响的研究仍然较少,机理研究同样需要加强;生物多样性对生态系统功能影响的环境依赖和尺度推演、生物多样性对生态系统多功能性的作用机理和量化方法是当前研究面临的挑战;生物多样性对生态系统响应气候变化的作用机制尚无统一的认识;生物多样性对气候变化的正、负反馈效应是国内外研究的盲点。最后,本文展望了未来发展方向和需要解决的关键科学问题,包括多因子气候变化对生物多样性的影响;减缓和适应气候变化的措施如何惠益于生物多样性保护;生物多样性与生态系统功能的理论如何应用到现实世界;生物多样性保护对实现碳中和目标的贡献。 展开更多
关键词 气候变化 多维度生物多样性 尺度生物多样性 生态系统多功能性 反馈机制
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The below-ground biomass contributes more to wetland soil carbon pools than the above-ground biomass-a survey based on global wetlands
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作者 Yueyan Pan Jiakai Liu +6 位作者 Mingxiang Zhang Peisheng Huang Matt Hipesy Liyi Dai Ziwen Ma Fan Zhang Zhenming Zhang 《Journal of Plant Ecology》 SCIE CSCD 2024年第5期17-28,共12页
The biomass of wetland plants is highly responsive to environmental factors and plays a crucial role in the dynamics of the soil organic carbon(SOC)pool.In this study,we collected and analyzed global data on wetland p... The biomass of wetland plants is highly responsive to environmental factors and plays a crucial role in the dynamics of the soil organic carbon(SOC)pool.In this study,we collected and analyzed global data on wetland plant biomass from 1980 to 2021.By examining 1134 observations from 182 published papers on wetland ecosystems,we created a comprehensive database of wetland plant above-ground biomass(AGB)and below-ground biomass(BGB).Using this database,we analyzed the biomass characteristics of different climate zones,wetland types and plant species globally.Based on this,we analyzed the differences between the biomass of different plant species and the linkage between AGB and BGB and organic carbon.Our study has revealed that wetland plant AGB is greater in equatorial regions but BGB is highest in polar areas,and lowest in arid and equatorial zones.For plant species,the BGB of the Poales is higher than the AGB but Caryophyllales,Cyperales and Lamiales have higher AGB.Moreover,our findings indicate that BGB plays a more significant role in contributing to the organic carbon pool compared to AGB.Notably,when BGB is less than 1 t C ha^(-1),even slight changes in biomass can have a significant impact on the organic carbon pool.And we observed that the SOC increases by 5.7 t C ha^(-1)when the BGB content is low,indicating that the SOC is more sensitive to changes in biomass under such circumstances.Our study provides a basis for the global response of AGB and BGB of wetland plants to organic carbon. 展开更多
关键词 plant biomass global scale organic carbon pool organic carbon sensitivity WETLAND
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制造纳米硅的新方法
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《航空精密制造技术》 北大核心 2001年第3期21-21,共1页
关键词 纳米硅 生物传感器 纳米结构 研究人员 微处理器 硅显示器 生物尺度 高密度数据 计算机电路 磁性材料
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UAVs as remote sensing platforms in plant ecology:review of applications and challenges 被引量:2
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作者 Zhongyu Sun Xiaonian Wang +3 位作者 Zhihui Wang Long Yang Yichun Xie Yuhui Huang 《Journal of Plant Ecology》 SCIE CSCD 2021年第6期1003-1023,共21页
Aims Unmanned aerial vehicles(UAVs),i.e.drones,have recently emerged as cost-effective and flexible tools for acquiring remote sensing data with fine spatial and temporal resolution.It provides a new method and opport... Aims Unmanned aerial vehicles(UAVs),i.e.drones,have recently emerged as cost-effective and flexible tools for acquiring remote sensing data with fine spatial and temporal resolution.It provides a new method and opportunity for plant ecologists to study issues from individual to regional scales.However,as a new method,UAVs remote sensing applications in plant ecology are still challenged.The needs of plant ecology research and the application development of UAVs remote sensing should be better integrated.Methods This report provides a comprehensive review of UAV-based remote sensing applications in plant ecology to synthesize prospects of applying drones to advance plant ecology research.Important Findings Of the 400 references,59%were published in remote sensing journals rather than in plant ecology journals,reflecting a substantial gap between the interests of remote sensing experts and plant ecologists.Most of the studies focused on UAV remote sensing’s technical aspects,such as data processing and remote sensing inversion,with little attention on answering ecological questions.There were 61%of studies involved community-scale research.RGB and multispectral cameras were the most used sensors(75%).More ecologically meaningful parameters can be extracted from UAV data to better understand the canopy surface irregularity and community heterogeneity,identify geometrical characteristics of canopy gaps and construct canopy chemical assemblies from living vegetation volumes.More cooperation between plant ecologists and remote sensing experts is needed to promote UAV remote sensing in advancing plant ecology research. 展开更多
关键词 UAVS DRONES unmanned aircraft systems(UASs) plant ecology species identification community function
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Selecting the Appropriate Urban Biodiversity Restoration Indices based on the Pressure-State-Response Model and a Multi-scale Management Problem Investigation in Zhuhai City 被引量:1
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作者 LI Fen GAO Nannan +3 位作者 PENG Rui HE Longbin LAI Yupei YANG Shiqi 《Journal of Resources and Ecology》 CSCD 2022年第3期518-527,共10页
Urban biodiversity is now recognized as playing a critical role in supporting global biodiversity.However,it is important to note that biodiversity is a systematic and holistic concept and prior studies have not gener... Urban biodiversity is now recognized as playing a critical role in supporting global biodiversity.However,it is important to note that biodiversity is a systematic and holistic concept and prior studies have not generally focused on cross-border or multi-scale management problems.On one hand,the ecosystems of cities are interconnected with adjacent cities by natural landscapes,so they are like mosaics instead of being isolated.Urban biodiversity research demands the consideration of the continuity within an ecosystem.On the other hand,both active protection and passive restoration strategies for urban biodiversity should not only be developed by researchers or municipal government agencies,but more importantly,they should consider the real ecosystem management problems faced by multi-scale departments in order to build a practicable Pressure-State-Response(PSR)model.The solutions for these issues should be included in the analysis to form a complete and more effective urban biodiversity strategy.The study in this paper offers an answer to whether different scales of cities or districts should adopt the same biodiversity strategy;and therefore,the decision depends on whether the places are of the same importance to the global or regional ecosystem,or whether the ecological elements are connected to the adjacent cities/districts and the problems that multiple stakeholders care about. 展开更多
关键词 biodiversity restoration multi-scale management urban biodiversity ECOSYSTEM multi-stakeholders
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Nitrogen addition affects plant biomass allocation but not allometric relationships among different organs across the globe 被引量:9
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作者 Kai Yue Dario A.Fomara +7 位作者 Wang Li Xiangyin Ni Yan Peng Shu Liao Siyi Tan Dingyi Wang Fuzhong Wu Yusheng Yang 《Journal of Plant Ecology》 SCIE CSCD 2021年第3期361-371,共11页
Aims Biomass allocation to different organs is a fundamental plant ecophysiological process to better respond to changing environments;yet,it remains poorly understood how patterns of biomass allocation respond to nit... Aims Biomass allocation to different organs is a fundamental plant ecophysiological process to better respond to changing environments;yet,it remains poorly understood how patterns of biomass allocation respond to nitrogen(N)additions across terrestrial ecosystems worldwide.Methods We conducted a meta-analysis using 5474 pairwise observations from 333 articles to assess how N addition affected plant biomass and biomass allocation among different organs.We also tested the'ratio-based optimal partitioning'vs.the'isometric allocation,hypotheses to explain potential N addition effects on biomass allocation.Important Findings We found that(i)N addition significantly increased whole plant biomass and the biomass of different organs,but decreased rootrshoot ratio(RS)and root mass fraction(RMF)while no effects of N addition on leaf mass fraction and stem mass fraction at the global scale;(ii)the effects of N addition on ratio-based biomass allocation were mediated by individual or interactive effects of moderator variables such as experimental conditions,plant functional types,latitudes and rates of N addition and(iii)N addition did not affect allometric relationships among different organs,suggesting that decreases in RS and RMF may result from isometric allocation patterns following increases in whole plant biomass.Despite alteration of ratio-based biomass allocation between root and shoot by N addition,the unaffected allometric scaling relationships among different organs(including root vs.shoot)suggest that plant biomass allocation patterns are more appropriately explained by the isometric allocation hypothesis rather than the optimal partitioning hypothesis.Our findings contribute to better understand N-induced effects on allometric relationships of terrestrial plants,and suggest that these ecophysiological responses should be incorporated into models that aim to predict how terrestrial ecosystems may respond to enhanced N deposition under future global change scenarios. 展开更多
关键词 meta-analysis ALLOMETRY biomass fraction ECOSYSTEM plant functional type global
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Human activity affects the perception of risk by mule deer 被引量:3
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作者 Mary V. PRICE Evelyn H. STROMBOM Daniel T. BLUMSTEIN 《Current Zoology》 SCIE CAS CSCD 2014年第6期693-699,共7页
Human activity has been shown to influence how animals assess the risk of predation, but we know little about the spatial scale of such impacts. We quantified how vigilance and flight behavior in mule deer Odocoileus ... Human activity has been shown to influence how animals assess the risk of predation, but we know little about the spatial scale of such impacts. We quantified how vigilance and flight behavior in mule deer Odocoileus hemionus varied with distance from an area of concentrated human activity--a subalpine field station. An observer walked trails at various distances away from the station looking for deer. Upon encounter, the observer walked toward the focal animal and noted the distance at which it alerted and directed its attention to the approaching human (Alert Distance; AD), and the distance at which it fled (Flight Initiation Distance;. FID). AD and FID both increased nonlinearly with distance from the center of the field station, reaching pla- teaus around 250 m and 750 m, respectively. Deer also tended to flee by stotting or running, rather than by walking, when far from the station but they walked away when near the station. These results indicate that deer perceive lower risk near a focused area of human activity, and that vigilance and flight behaviors respond on somewhat different spatial scales. The concept of a spatial "human footprint" on behavior may be useful for understanding how human activities affect wildlife 展开更多
关键词 Flight initiation distance Alert distance Predation risk assessment Human disturbance Mule deer Odocoileushemionus VIGILANCE
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Effects of sediment physical properties on the phosphorus release in aquatic environment 被引量:9
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作者 ZHU HongWei WANG DaoZeng +2 位作者 CHENG PengDa FAN JingYu ZHONG BaoChang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第2期82-89,共8页
Particle size, porosity, and the initial phosphorus concentration in sediments are the main factors affecting phosphorus release flux through the sediment-water interface. Sediments can be physically divided to muddy ... Particle size, porosity, and the initial phosphorus concentration in sediments are the main factors affecting phosphorus release flux through the sediment-water interface. Sediments can be physically divided to muddy and sandy matters, and the adsorption-desorption capacity of sediment with phosphorus depends on particle size. According to phosphorus adsorption-desorption experiments, phosphorus sorption capacity of the sediment decreases with the increase of particle dimension. But among the size-similar particles, sediment with a bigger particle size has the larger initial phosphorus release rate. In terms of muddy and sandy sediments, there are inversely proportional relationships between the release rate and the flux. Due to the contact of surface sediment and the overlying water, the release flux from the sediment is either from direct desorption of surface sediment layer or from the diffusion of pore water in the sediment layer, which is mainly determined by sediment particle size and porosity. Generally, static phosphorus release process may include two stages: the first is the initial release. As for coarse particles, phosphorus is desorbed from surface sediment. And for fine particles, phosphorus concentration in water often decreases, mainly from pore water by the molecular diffusion. During the second stage, pore water flows faster in coarse sediment, and phosphorus is easy to desorb from the surface of the particles as diffusion dominates. For the smaller liquid-solid ratio of fine particles and the larger amount of phosphorus adsorption, the release flux from pore water due to diffusion is very small with longer sorption duration. 展开更多
关键词 sediments pollutants particle size POROSITY phosphorus desorption molecular diffusion
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