城市乔木树种多样性遥感反演方法研究

量化城市乔木树种多样性是定量研究其生态系统服务的前提和基础。目前,城市树种多样性水平的定量研究以地面调查方法为主,存在效率低、成本高的问题。针对上述问题,首先验证了光谱变异性假说和生产力假说在城市中的适用性,进而提出了快速量化城市树种多样性水平的方法。该方法基于神经网络刻画了乔木斑块多样性与光谱异质性之间的关系,能够较准确地反演城市乔木的香浓维纳指数和辛普森指数。为城市乔木树种多样性的调查提供了新的思路,并将为定量研究城市乔木多样性的生态系统服务提供基础数据。     

基于地面调查的植被生态质量综合评估指标体系构建

植被是陆地生态系统的主体,是保障生态质量的基础,也是基于自然的生态系统增汇、实现“碳中和”的重要利器。植被是生态质量评价的核心要素,但目前的生态质量评价研究中所用到的植被指标多是通过遥感反演或者气象指数模型计算得到的,而基于典型生态系统尺度地面调查的植被观测数据更直接、更准确,数据也很丰富,却很少用于生态质量评价,也缺乏系统的评价指标体系。通过文献研究、专家研讨和问卷调查,并借鉴群落退化演替和生态系统长期监测研究的理论基础,构建基于地面调查的植被生态质量综合评估指标体系。该指标体系整体分为三级,一级综合指数由群落结构指数、物质生产指数、生物多样性指数、群落发展或者演替趋势4个二级分项指标构成,二级分项指标由12—14个三级指标组成,不同植被类型各有其特征指标。该体系将完善我国多尺度陆地生态系统的生态质量评价指标体系,为新时期国家生态质量评价提供科学建议,为我国生态文明建设提供技术支撑。     

FQA:一种基于物种保守性的植物区系质量评价方法

植物区系质量评价法(FQA)是一种利用植物物种对特定生境的保守性和植物群落的物种丰富度快速评估栖息地质量的方法.基于样方物种组成和专家赋值的植物物种保守系数,运用简单的公式即可计算出样方的植物区系质量指数(FQI).该指数能够反映植被的完整性和退化程度,可以用于对栖息地质量进行时空对比,已经在美国、加拿大等十余个国家广泛应用.本文介绍该方法的原理、计算公式和应用案例,为生态管理工作者和研究人员提供一种简单、可重复、可对比的生境质量评估工具.     

基于地面观测的陆地生态系统碳储量多源数据整合方法

陆地生态系统有机碳储量通常指一定面积的植被、土壤和凋落物的有机碳存储量总和。准确评估陆地生态系统碳储量现状和变化,对于揭示全球变化对陆地生态系统碳库的影响、指导政府决策者制定气候应对策略和评估现有措施的有效性等具有重要意义。地面观测数据是生态系统碳储量及其变化评估的重要数据源之一,但目前除少数生态站开展了长期地面数据观测外,绝大多数地面观测数据呈现出多源化、相互不匹配、时间不连续等特点;因此,迫切需要发展科学、规范化的多源数据整合方法,将这些多源、分散的地面观测数据整编形成长期系统的地面动态观测数据集,提高数据资源价值。从陆地生态系统碳储量组分及其基本算法着手,系统梳理了植被和土壤碳储量估算中植被不同器官生物量和碳含量、土壤碳含量、土壤容重等关键参数的观测现状,并详细介绍了这些关键参数的科学推导方法。此外,也进一步讨论了多源地面观测碳储量数据整合的方法,并展望了该方法体系未来的发展方向,期待能为后续相关研究提供可借鉴的规范性方法。     

四种常绿乔木潜在及未来分布区模拟研究

基于《中国木本植物分布图集》和Arc GIS地理信息平台,通过Climate China模型提取2000s(1990-2009)、2020s(2010-2039)、2050s(2040-2069)三个时段的13个气候变量数据为主要气候信息源,采用最大熵法(MaxEnt)生态位模型对四种常绿乔木在中国范围的潜在适生分布区进行模拟预测,得出该四种乔木在2000s、2020s、2050s的分布变化。结果表明:MaxEnt生态位模型模拟的该四种常绿乔木潜在适生分布范围大于文献记载中的分布区域;影响该四种常绿乔木分布的主要气候变量并不完全一致;在未来气候变化下,该四种常绿乔木潜在适生分布区的变化趋势不同。研究结果可为植物适生区划、园林绿化树种引种栽培区的选择提供理论指导。     

色木槭天然次生林群落结构特征

对色木槭天然次生林群落进行研究,测定了该群落主要乔木树种的重要值,分析了该群落的种类组成,物种多样性。结果表明：色木槭天然次生林乔木层共有16个种群,其中色木槭、蒙古栎、糠椴、山榆占明显优势,为该层的优势种和建群种;径级以<15 cm的株数最多,占总株数的87.82%,林分幼树更新数量充足。群落的Simpson指数为0.833、Shannon-wiener多样性指数为2.101、丰富度指数为2.291、均匀性指数为0.758和生态优势度指数为0.113。乔木层立木以低龄种群在群落中占优势,为了促进群落将向地带性典型植被类型演替,提出了抚育管理的建议。     

绿地格局对城市地表热环境的调节功能

城市绿地作为一种稀缺资源,为城市可持续发展提供多种生态服务功能保障.探讨如何在有限的土地资源内合理配置城市绿地,使其发挥最大的生态服务功能非常重要.研究基于北京市2002年7月的QuickBird数据和Landsat 7 ETM+数据分别提取城市绿地格局和地表温度,分析城市绿地格局(绿地面积、形状指数、邻接关系)与绿地地表温度及冷岛强度的相关关系.邻接关系包括邻接绿地斑块个数百分比和邻接绿地斑块面积百分比.邻接绿地斑块面积百分比采用缓冲区分析法,主要以乔木林地对地表热环境的调节作用为例.结果表明绿地格局参数对地表温度的影响相差较大:①城区主要的绿地类型(乔木林地、水体、草地)的温度都与其面积呈显著负相关,其中水体的相关系数最高;②只有乔木林地、水体的温度与其形状指数呈显著负相关,而灌木林地的温度与各个格局参数不相关;③乔木林地的缓冲区分析显示温度与其大小、形状、邻接绿地面积百分比关系都呈负相关,其中与邻接绿地面积百分比的相关关系最强,其冷岛强度也主要受邻接绿地面积百分比的影响.基于遥感识别的城市绿地微气候调节功能研究,有助于提高有限的城市绿地的生态服务功能,并可为城市绿地的规划管理和景观分析提供依据.     

近20年辽宁省植被动态特征及其对气候变化的响应

区域归一化植被指数(NDVI)变化特征对环境容量和生态发展方向有重要指示作用。基于SPOT/VEGETATION NDVI数据和ESA CCI-LC植被分类数据,利用Theil-Sen+Mann-Kendall、变异系数、Hurst指数和相关性分析方法,对辽宁省2000—2019年不同植被类型归一化植被指数时空变化特征和气候因子之间的响应关系进行分析。结果表明：(1)NDVI均值呈现从乔木到草原逐渐降低的趋势,不同植被类型在生长季具有不同的生长习性;(2)各植被类型都呈增加趋势,结合Hurst指数和Sen趋势,辽宁省36.26%的植被将趋于改善,约有61.51%的植被将趋于退化;(3)变异系数结果表明：所有植被类型中以乔木植被最为稳定,草原型植被最不稳定。(4)辽宁省各植被类型NDVI与降水显著正相关,与气温相关性相对较低。结果可为辽宁省生态评价和碳循环研究提供植被覆盖动态参考。     

基于探索性空间数据分析的海坛岛土地利用生态风险评价

生态风险评价作为一种新型环境管理工具,提供了定量化评估土地利用变化生态效应的新视角.本研究以福建海坛岛为案例区,基于1990年Landsat TM与2010年SPOT5遥感影像、2030年平潭综合试验区总体布局规划图和野外调查等数据,构建度量生态终点的生态风险表征指数,运用探索性空间数据分析中的空间自相关和半方差分析方法,对海坛岛过去 现在 未来不同土地利用情景下生态风险进行评价,分析其潜在的风险性及其变化趋势.结果表明： 海坛岛生态风险指数存在明显的尺度效应,在3000 m范围内表现出较强的正相关,生态风险指数空间分布以高 高聚集和低 低聚集类型为主;生态风险指数具有显著的各向同性特点,且其空间分布与对应时期局部空间自相关指数分布模式一致;各生态风险等级区年际变化较为剧烈,波动态势与波动幅度均有所不同;低生态风险区呈先增后降趋势,中、高生态风险区呈先降后升趋势.规划期的人为扰动强烈,高生态风险区在整个区域扩展蔓延.为减低土地利用生态风险、维护区域生态安全,可采取的生态风险控制策略包括：优化土地资源空间格局、保护关键生态区域、控制建设用地规模.
     

运用植物区系质量指数快速评估湿地植被恢复成效

目前通常采用的评估湿地保护和恢复成效的指标体系较为复杂, 常涉及生物学、环境科学和社会学等多个学科, 导致监测评估成本高, 并难以实现综合的定量评估, 因此有必要提出能够在较大程度上表达生态环境状况的综合生态指标。植物区系质量指数(Floristic Quality Assessment Index, FQAI)反映了植物区系中物种的生态保守性程度, 作者将其作为主要生态指标, 来验证该指标用于湿地植被恢复成效定量评估的有效性。作者以四川盆地丘陵和平原地区湿地植物为对象, 构建了区域库塘及河滩湿地植物区系质量指数计算方法与赋值表, 以成都市重要水源地——云桥湿地的3年生态恢复成效为案例进行了检验。结果表明, 在云桥湿地3年恢复期间, 植物物种组成及其比例在恢复年限间无显著差异, Shannon-Wiener指数、Pielou指数和Simpson指数在3年中也并未发生显著变化, 但生态保守性系数平均值(CC_mean)和植物区系质量指数(FQAI)均随恢复年限显著上升, 表明FQAI可以快速、有效地实现生态系统水平湿地植被恢复成效的比较和定量评估。     

A new assessment method for the quality of ecological monitoring data: taking CERN's tree growth dataset as a case

This paper presented a new and simple assessment method for the quality of ecological monitoring data. This method theorized the associations between the data reliability as an ordinal variable with different number of classes and the data sources such as natural main ecological processes, secondary ecological processes, and extraneous and exotic processes, and offered a new data quality index to estimate the quality of the whole dataset by using the reasonableness ratio of observations. The assessment results provided the reliability class of each dataset, good explanations for outlier (or error data) flagging decisions, and quality value of the whole dataset. The method was applied to assess two tree growth datasets from Chinese Ecosystem Research Network (CERN), and the results demonstrated that the new data quality index could quantitatively evaluate the quality of the tree growth datasets. The new method would facilitate the development of corresponding software.     

Ecobat: An online resource to facilitate transparent,evidence‐based interpretation of bat activity data

Acoustic surveys of bats are one of the techniques most commonly used by ecological practitioners. The results are used in Ecological Impact Assessments to assess the likely impacts of future developments on species that are widely protected in law, and to monitor developments’ postconstruction. However, there is no standardized methodology for analyzing or interpreting these data, which can make the assessment of the ecological value of a site very subjective. Comparisons of sites and projects are therefore difficult for ecologists and decision‐makers, for example, when trying to identify the best location for a new road based on relative bat activity levels along alternative routes. Here, we present a new web‐based, data‐driven tool, Ecobat, which addresses the need for a more robust way of interpreting ecological data. Ecobat offers users an easy, standardized, and objective method for analyzing bat activity data. It allows ecological practitioners to compare bat activity data at regional and national scales and to generate a numerical indicator of the relative importance of a night's worth of bat activity. The tool is free and open‐source; because the underlying algorithms are already developed, it could easily be expanded to new geographical regions and species. Data donation is required to ensure the robustness of the analyses; we use a positive feedback mechanism to encourage ecological practitioners to share data by providing in return high quality, contextualized data analysis, and graphical visualizations for direct use in ecological reports.     

Temporal degradation of data limits biodiversity research

Spatial and/or temporal biases in biodiversity data can directly influence the utility, comparability, and reliability of ecological and evolutionary studies. While the effects of biased spatial coverage of biodiversity data are relatively well known, temporal variation in data quality (i.e., the congruence between recorded and actual information) has received much less attention. Here, we develop a conceptual framework for understanding the influence of time on biodiversity data quality based on three main processes: (1) the natural dynamics of ecological systems—such as species turnover or local extinction; (2) periodic taxonomic revisions, and; (3) the loss of physical and metadata due to inefficient curation, accidents, or funding shortfalls. Temporal decay in data quality driven by these three processes has fundamental consequences for the usage and comparability of data collected in different time periods. Data decay can be partly ameliorated by adopting standard protocols for generation, storage, and sharing data and metadata. However, some data degradation is unavoidable due to natural variations in ecological systems. Consequently, changes in biodiversity data quality over time need be carefully assessed and, if possible, taken into account when analyzing aging datasets.     

面向生态系统评估的多源数据融合体系

基于生态系统服务功能的生态系统评估是识别生态环境问题、开展生态系统恢复和生物多样性保护、建立生态补偿机制的重要基础,也是保障国家生态安全、推进生态文明建设的重要环节。生态系统评估涉及生态系统多个方面,需要多要素、多类型、多尺度的生态系统观测数据作为支撑。地面观测数据和遥感数据是生态系统评估的两大数据源,但是其在使用时常存在观测标准不一、观测要素不全面、时间连续性不足、尺度不匹配等问题,给生态系统评估增加了极大的不确定性。如何融合不同尺度的观测数据量化生态系统服务功能是实现生态系统准确评估的关键。为此,从观测尺度出发,阐述了地面观测数据、近地面遥感数据、机载遥感数据和卫星遥感数据的特点及其在问题,并综述了这几类数据源进行融合的常用方法,并以生产力、固碳能力、生物多样性几个关键生态参数为例介绍了“基于多源数据融合的生态系统评估技术及其应用研究”项目的多源数据融合体系。最后,总结面向生态系统评估的多源数据融合体系,并指出了该研究的未来发展方向。     

Impact of abundance data errors on the uncertainty of an ecological water quality assessment index

Increased awareness about the uncertainty of ecological water quality (EWQ) assessment tools in river management has led to the identification of the underlying uncertainty sources and the quantification of their effect on assessment. More specifically, with respect to macroinvertebrate-based EWQ assessment, use of erroneous abundance data has been identified as a (possible) source of uncertainty. In this paper, the effect of erroneous abundance data on the uncertainty of an EWQ assessment index was investigated. A model simulation based method, the virtual ecologist approach, was used to estimate the impact of abundance data errors on the uncertainty of the Multimetric Macroinvertebrate Index Flanders (MMIF). The results of this study show that the effects of relative small errors on the MMIF and assessment are limited. Additionally, it is observed that uncertainties due to abundance errors increase with decreasing EWQ (i.e. lower MMIF). This is important, since decision-makers typically formulate management actions for rivers with a low EWQ. In short, the innovative virtual ecologist approach proved to be very successful to research the index uncertainty and present a unique insight in the functioning of the assessment index.     

An appraisal of a biocontamination assessment method for freshwater macroinvertebrate assemblages; a practical way to measure a significant biological pressure?

Freshwater invasive or alien species (IAS) can have a major impact on benthic macroinvertebrate assemblage structure and diversity. This has implications for accurate biological monitoring, the assessment of the ecological quality status of rivers and achievement of Water Framework Directive (WFD) objectives. Although IAS constitutes a major biological pressure to WFD objectives, current approaches to ecological status assessment tend to ignore their presence. This problem is compounded as biotic indices such as the Biological Monitoring Working Party (BMWP) score do not distinguish between native and IAS, when IAS tend to be more tolerant of organic pollution than the natives they replace. Biocontamination is the presence of an IAS in a system, and we tested a new method of biocontamination assessment, designed to be used alongside current routine water quality monitoring techniques, by applying it to biological monitoring data from the river monitoring programme of a small Island, The Isle of Man. Although 54% of monitoring sites exhibited no biocontamination, 19% showed low or moderate biocontamination and 27% high or severe biocontamination. Richness contamination was low (only two contaminated families being recorded), but abundance contamination was high in some sites (87% of individuals being IAS). Sites with a greater relative abundance of IAS individuals exhibited lower BMWP water quality. Within invaded sites BMWP monitoring was not responsive to changing chemical water quality, whereas within uninvaded sites it was. In invaded sites, the relative abundance of IAS increased as ammonia and BOD₅ increased. Our study shows current monitoring approaches mask the presence of AIS within assemblages, with some highly biocontaminated sites registering high BMWP biological quality. This new index represents a simple way to integrate the IAS biological pressure into established WFD monitoring programmes, to produce more comprehensive estimates of ecological quality status than are currently being realised.     

Enhancing Life-Cycle Inventories via Reconciliation with the Laws of Thermodynamics

Abstract: Obtaining reliable results from life-cycle assessment studies is often quite difficult because life-cycle inventory (LCI) data are usually erroneous, incomplete, and even physically meaningless. The real data must satisfy the laws of thermodynamics, so the quality of LCI data may be enhanced by adjusting them to satisfy these laws. This is not a new idea, but a formal thermodynamically sound and statistically rigorous approach for accomplishing this task is not yet available. This article proposes such an approach based on methods for data rectification developed in process systems engineering. This approach exploits redundancy in the available data and models and solves a constrained optimization problem to remove random errors and estimate some missing values. The quality of the results and presence of gross errors are determined by statistical tests on the constraints and measurements. The accuracy of the rectified data is strongly dependent on the accuracy and completeness of the available models, which should capture information such as the life-cycle network, stream compositions, and reactions. Such models are often not provided in LCI databases, so the proposed approach tackles many new challenges that are not encountered in process data rectification. An iterative approach is developed that relies on increasingly detailed information about the life-cycle processes from the user. A comprehensive application of the method to the chlor-alkali inventory being compiled by the National Renewable Energy Laboratory demonstrates the benefits and challenges of this approach.     

Integrating models with data in ecology and palaeoecology: advances towards a model-data fusion approach

It is increasingly being recognized that global ecological research requires novel methods and strategies in which to combine process-based ecological models and data in cohesive, systematic ways. Model-data fusion (MDF) is an emerging area of research in ecology and palaeoecology. It provides a new quantitative approach that offers a high level of empirical constraint over model predictions based on observations using inverse modelling and data assimilation (DA) techniques. Increasing demands to integrate model and data methods in the past decade has led to MDF utilization in palaeoecology, ecology and earth system sciences. This paper reviews key features and principles of MDF and highlights different approaches with regards to DA. After providing a critical evaluation of the numerous benefits of MDF and its current applications in palaeoecology (i.e., palaeoclimatic reconstruction, palaeovegetation and palaeocarbon storage) and ecology (i.e. parameter and uncertainty estimation, model error identification, remote sensing and ecological forecasting), the paper discusses method limitations, current challenges and future research direction. In the ongoing data-rich era of today's world, MDF could become an important diagnostic and prognostic tool in which to improve our understanding of ecological processes while testing ecological theory and hypotheses and forecasting changes in ecosystem structure, function and services.     

An overall assessment of Life Cycle Inventory quality

A qualitative, quantitative, and overall quality assessment of life cycle inventory is suggested. The method is composed of five indicators which are set up at three levels of the inventory quality: flows, processes, and the system. The method allows one to assess the reliability of the method generating inventory data (justness of data, completeness of data, representativity of processes, repeatability of system definition) and at the same time to quantify the uncertainty of the resulting data made under the data generation method. LCA practitioners can finally decide the overall inventory quality through the information for the acceptability of the inventory result comparing the objective of quality and the cost necessary to improve the quality. The operation of the method was verified in the application to the production of polyethylene bottles. The proposed method was also found applicable for the validation of data in the ISO’s LCA data documentation format.