中国森林遥感Rao′s Q指数时空演变

明确宏观森林植物多样性时空分布格局,对于评估森林生态工程效果以及有效开展区域生物多样性保护工作具有重要意义。遥感生物多样性研究能够弥补原位观测在时空连续性方面的不足,研究旨在为区域尺度生物多样性研究引入一种新方法——遥感Rao′s Q指数。结果表明：基于归一化植被指数(NDVI)计算的Rao′s Q指数与收集的物种丰富度在空间分布上基本一致,且两者的数值拟合通过极显著检验(R²=0.66,P<0.001),Rao′s Q指数随物种丰富度增加而增加,适用于表征宏观尺度跨气候带地区的森林植物多样性。2000—2017年间,中国森林的Rao′s Q指数时空分布基本一致,整体呈南高北低的态势;不同时段中均以降低为主,降低面积占总面积的44.23%—54.08%,武夷山-南岭一带增高特征凸显,而2010—2017年也表现出降低特征,该区域森林植物多样性本底丰富,应加强管控力度,阻止降低热点区扩散。引入遥感Rao′s Q指数有效表征区域森林植物多样性分布特征,可为区域生态质量评估提供一种新的监测指标,进而为森林植物多样性保护及区域生态质量改善相关政策制定提供支撑。     

Monitoring ecological indicators of rangeland functional integrity and their relation to biodiversity at local to regional scales

Abstract Functional integrity is the intactness of soil and native vegetation patterns and the processes that maintain these patterns. In Australia's rangelands, the integrity of these patterns and processes have been modified by clearing, grazing and fire. Intuitively, biodiversity should be strongly related to functional integrity; that is, landscapes with high functional integrity should maintain biodiversity, and altered, less functional landscapes may lose some biodiversity, defined here as the variety and abundance of the plants, animals and microorganisms of concern. Simple indicators of biodiversity and functional integrity are needed that can be monitored at a range of scales, from fine to coarse. In the present paper, we use examples, primarily from published work on Australia's rangeland, to document that at finer patch and hillslope scales several indicators of landscape functional integrity have been identified. These indicators, based on the quantity and quality of vegetation patches and interpatch zones, are related to biodiversity. For example, a decrease in the cover and width (quantity) and condition (quality) of vegetation patches, and an increase in bare soil (quantity of interpatch) near cattle watering points in a paddock are significantly related to declines in plant and grasshopper diversity. These vegetation patch‐cover and bare‐soil indicators have been monitored traditionally by field‐based methods, but new high‐resolution, remote‐sensing imagery can be used in specific rangeland areas for this fine‐scale monitoring. At intermediate paddock and small watershed scales, indicators that can be derived from medium‐resolution remote‐sensing are also needed for efficient monitoring of rangeland condition (i.e. functional integrity) and biodiversity. For example, 30–100‐m‐pixel Landsat imagery has been used to assess the condition of rangelands along grazing gradients extending from watering‐points. The variety and abundance of key taxa have been related to these gradients (the Biograze project). At still larger region and catchment scales, indicators of rangeland functional integrity can also be monitored by coarse‐resolution remote‐sensing and related to biodiversity. For example, the extent and greenness (condition) of different regional landscapes have been monitored with 1‐km‐pixel satellite imagery. This regional information becomes more valuable when it indicates differences as a result of land management. Finally, we discuss potential future developments that could improve proposed indicators of landscape functional integrity and biodiversity, thereby improving our ability to monitor rangelands effectively.     

Tree species richness decreases while species evenness increases with disturbance frequency in a natural boreal forest landscape

Understanding species diversity and disturbance relationships is important for biodiversity conservation in disturbance‐driven boreal forests. Species richness and evenness may respond differently with stand development following fire. Furthermore, few studies have simultaneously accounted for the influences of climate and local site conditions on species diversity. Using forest inventory data, we examined the relationships between species richness, Shannon''s index, evenness, and time since last stand‐replacing fire (TSF) in a large landscape of disturbance‐driven boreal forest. TSF has negative effect on species richness and Shannon''s index, and a positive effect on species evenness. Path analysis revealed that the environmental variables affect richness and Shannon''s index only through their effects on TSF while affecting evenness directly as well as through their effects on TSF. Synthesis and applications. Our results demonstrate that species richness and Shannon''s index decrease while species evenness increases with TSF in a boreal forest landscape. Furthermore, we show that disturbance frequency, local site conditions, and climate simultaneously influence tree species diversity through complex direct and indirect effects in the studied boreal forest.     

Assessing current and projected suitable habitats for tree-of-heaven along the Appalachian Trail

The invasion of ecosystems by non-native species is a major driver of biodiversity loss worldwide. A critical component of effective land management to control invasion is the identification and active protection of areas at high risk of future invasion. The Appalachian Trail Decision Support System (A.T.-DSS) was developed to inform regional natural resource management by integrating remote sensing data, ground-based measurements and predictive modelling products. By incorporating NASA''s remote sensing data and modelling capacities from the Terrestrial Observation and Prediction System (TOPS), this study examined the current habitat suitability and projected suitable habitat for the invasive species tree-of-heaven (Ailanthus altissima) as a prototype application of the A.T.-DSS. Species observations from forest surveys, geospatial data, climatic projections and maximum entropy modelling were used to identify regions potentially susceptible to tree-of-heaven invasion. The modelling result predicted a 48% increase in suitable area over the study area, with significant expansion along the northern extremes of the Appalachian Trail.     

基于功能性状的中亚热带岩溶常绿落叶阔叶混交林物种多样性维持研究

理解植物功能性状和功能实体在森林群落的分布,有助于探讨物种丧失对森林生态系统功能、冗余和恢复力的影响。为了解脆弱的岩溶石山森林在应对生物多样性丧失的生态系统反馈,对桂林岩溶石山两块1hm²的常绿落叶阔叶混交林的木本植物数据进行了分析。包括基于功能性状计算功能多样性、构建功能实体计算功能冗余以及采用Pearson相关分析和Mantel检验评估物种多样性指标在生态系统的维持机制。结果显示:(1)青冈+大叶榉树群落的功能多样性指标均低于鱼骨木+青冈+圆叶乌桕群落,且两个群落间功能均匀度不相关(P ＞ 0.05),功能丰富度、功能离散度和Rao''s二次熵呈现极显著相关性(P ＜ 0.001),功能分散度呈现显著相关性(P ＜ 0.05)。(2)两个群落的物种丰富度与功能冗余指标表现出相似的线性关系,即物种丰富度与功能实体等级、功能冗余、功能超冗余呈正相关,与功能脆弱性呈负相关关系。(3)不同植物功能性状间、不同功能多样性指标间和不同功能冗余指标间的相关性较强,功能多样性指标和功能冗余指标间无显著相关性,但功能性状与功能多样性指标、功能性状与功能冗余指标均存在不同程度的相关性。而在功能实体与物种多样性指标的相关性方面,呈现出同物种丰富度与物种多样性指标相似的显著度。另外,物种多度与物种丰富度、功能分散度、功能离散度、Rao''s二次熵及功能脆弱性均显著相关。总之,在岩溶石山常绿落叶阔叶混交林中,高功能多样性的群落存在高功能冗余的现象,但功能多样性和功能冗余是相互独立的因素;物种丰富度高的群落所提供的保险效应无法抵消其生态系统的脆弱性。因此,不能仅通过保护物种丰富度来维持生态系统的特有功能,还应充分考虑多度对生态系统功能的贡献,以更有效地实现对岩溶石山森林生态系统的保护。     

Remote sensing of biodiversity: what to measure and monitor from space to species?

Global biodiversity monitoring systems through remote sensing can support consistent assessment, monitoring, modelling and reporting on biodiversity which are key activities intended for sustainable management. This work presents an overview of biodiversity monitoring components, i.e. biodiversity levels, essential biodiversity variables, biodiversity indicators, scale, biodiversity inventory, biodiversity models, habitat, ecosystem services, vegetation health and biogeochemical heterogeneity and discusses what remote sensing through Earth Observations has contributed to the study of biodiversity. The technological advancements in remote sensing have enabled information-rich data on biodiversity. Remote sensing data are making a strong contribution in providing unique information relevant to various biodiversity research and conservation applications. The extensive use of Earth observation data are not yet realized in biodiversity assessment, monitoring and conservation. The development of direct remote sensing approaches and the techniques for quantifying biodiversity at the community to species level is likely to be a great challenge for comprehensive earth observation-based monitoring strategy.

     

A ‘fast-food approach’ to the standardization of quadratic diversity

Abstract

Intuitively, a community composed of ecologically dissimilar taxa is more diverse than a community composed of more similar taxa. However, since traditional diversity indices such as Shannon's entropy or Simpson's diversity are computed solely from the relative abundances of a given species assemblage, they cannot account for ecological differences between species. There have been recent developments regarding the use of quadratic entropy, a diversity index that incorporates both species relative abundances and a measure of the pairwise ecological differences between species. In this paper we firstly show that under some specific circumstances quadratic entropy can be additively decomposed into α- β- and γ-diversities, a property that renders it a desirable measure of diversity in the ecological practice. Next, we suggest a quick and simple method for obtaining a standardized version of quadratic entropy that may allow an easier interpretation of the resulting diversity values.     

The decomposition of Shannon's entropy and a confidence interval for beta diversity

Beta diversity is among the most employed theoretical concepts in ecology and biodiversity conservation. Up to date, a self‐contained definition of it, with no reference to alpha and gamma diversity, has never been proposed. Using Kullback‐Leibler divergence, we present the explicit formula of Shannon's β entropy, a bias correction for its estimator and a confidence interval. We also provide the mathematical framework to decompose Shannon diversity into several hierarchical nested levels. From botanical inventories of tropical forest plots in French Guiana, we estimate Shannon diversity at the plot, forest and regional level. We believe this is a complete and usefulness toolbox for ecologists interested in partitioning biodiversity.     

中国生物多样性核心监测指标遥感产品体系构建与思考

生物多样性的稳定维持关乎人类生存发展与地球健康。生物多样性核心监测指标(Essential Biodiversity Variables, EBVs)旨在结合地面调查与遥感技术, 为大尺度、长时间序列的生物多样性监测提供新的解决方案。然而, 目前学界仍然缺乏一套国家尺度标准化EBVs遥感监测产品数据集, 以进行生物多样性评估。本研究旨在对中国生物多样性核心监测指标遥感产品进行体系构建与思考, 首先综述了目前EBVs的遥感研究概况, 并根据EBVs研究文献的数量进行调研分析; 同时, 本文在已有遥感生物多样性产品优先标准的基础上, 添加了“可重复性”的新标准, 并据此构建了中国EBVs遥感产品体系与监测数据集的指标清单, 最终对中国EBVs遥感研究存在的问题进行思考与讨论。本研究可为中国的生物多样性遥感监测提供科学依据, 有望为中国生物多样性政策的制定提供支撑。     

Ecological complexity effects on thermal signature of different Madeira island ecosystems

From a systemic perspective, evolution and natural succession promote the creation of efficient biological structures and processes that capture and dissipate the solar energy, maximizing the entropy production. This ecological complexification results in better ecosystem thermodynamic performance indicated by lower temperature.In a brief period of evolutionary time human-induced disturbance has altered profoundly the structure and functioning of the Earth System, i.e. ecological simplification.The objective is to understand whether remote sensing data can be considered appropriate proxy indicators to test if more mature and complex ecosystems have higher entropy production rates which lead to lower and attenuated ecosystem temperatures.Simple remote sensing measurements of Madeira Island for Thermal Infrared Radiation and Normalized Difference Vegetation Index were used to analyse the surface temperature and biomass cover of Madeira ecosystems spectrum of different states of human-induced disturbance.The findings revealed it was possible to distinguish between ecosystem types using thermodynamic indicators, where older ecosystems with more complex structures exhibit more attenuated lower average temperatures.It was also found that habitat heterogeneity can represent either artificial (human) or natural disturbance with opposite consequences in the ecosystem thermal signature, i.e. lower temperature when natural disturbance and higher if anthropogenic disturbance.Simple thermal remote sensing data can be used as systemic indicator of ecosystem health by reflecting it levels of eco-exergy, i.e the available work energy in the ecosystem.     

遥感用于森林生物多样性监测的进展

随着物种和栖息地的丧失,全球范围的生物多样性保护已经成为迫切的需要。航空航天技术的迅猛发展使遥感成为能提供跨越不同时空尺度监测陆地生态系统生物多样性的重要工具,这方面的研究在欧美等国已经有了小范围的开展,在国内刚刚起步。国外关于生物多样性遥感探测的方法基本有3种:1.利用遥感数据直接对物种或生境制图,进而估算生物多样性;2 .建立遥感数据的光谱反射率与地面观测物种多样性的关系模型;3.与野外调查数据结合直接在遥感数据上进行生物多样性指数制图。研究表明,物种直接制图法只能应用于较小的范围;生境制图的方法,应用广泛,技术相对成熟,研究范围局限于几百公里的范畴,但不能获取生境内部的多样性信息。光谱模型技术目前正处于探索阶段,对于植被复杂、生物多样性高的地域,具有较大的应用潜力。在遥感数据上直接进行生物多样性制图在加拿大已经得到了应用。     

Ecohydrodynamics of Cold-Water Coral Reefs: A Case Study of the Mingulay Reef Complex (Western Scotland)

Ecohydrodynamics investigates the hydrodynamic constraints on ecosystems across different temporal and spatial scales. Ecohydrodynamics play a pivotal role in the structure and functioning of marine ecosystems, however the lack of integrated complex flow models for deep-water ecosystems beyond the coastal zone prevents further synthesis in these settings. We present a hydrodynamic model for one of Earth''s most biologically diverse deep-water ecosystems, cold-water coral reefs. The Mingulay Reef Complex (western Scotland) is an inshore seascape of cold-water coral reefs formed by the scleractinian coral Lophelia pertusa. We applied single-image edge detection and composite front maps using satellite remote sensing, to detect oceanographic fronts and peaks of chlorophyll a values that likely affect food supply to corals and other suspension-feeding fauna. We also present a high resolution 3D ocean model to incorporate salient aspects of the regional and local oceanography. Model validation using in situ current speed, direction and sea elevation data confirmed the model''s realistic representation of spatial and temporal aspects of circulation at the reef complex including a tidally driven current regime, eddies, and downwelling phenomena. This novel combination of 3D hydrodynamic modelling and remote sensing in deep-water ecosystems improves our understanding of the temporal and spatial scales of ecological processes occurring in marine systems. The modelled information has been integrated into a 3D GIS, providing a user interface for visualization and interrogation of results that allows wider ecological application of the model and that can provide valuable input for marine biodiversity and conservation applications.     

鄱阳湖湿地大型底栖无脊椎动物多样性对群落次级生产力及稳定性的影响

理解生物多样性对生态系统功能及稳定性的影响对于制定有效的保护管理策略有重要意义。然而,目前生物多样性与群落生产力、稳定性的关系仍存在争议。在鄱阳湖湿地布设30个采样点,于2019年秋季开展大型底栖无脊椎动物群落野外调查。基于底栖动物群落数据,采用广义加性模型分析物种、谱系、功能多样性对鄱阳湖湿地底栖动物群落次级生产力与稳定性的影响。结果表明:底栖动物群落的次级生产力与反映物种多样性的指数(Simpson多样性指数、Shannon-Wiener多样性指数、Pielou均匀度指数)、分类多样性指数、平均分类差异指数、功能丰富度指数等呈显著的负相关,其中Pielou均匀度指数与次级生产力的相关度最高(r²=0.33)。功能多样性对群落次级生产力的空间分异有最高的解释度(r²=0.75)。P/B值(次级生产力与生物量之比代表群落稳定性)与物种、谱系、功能多样性指数均呈正相关,其中功能丰富度与P/B值的相关度最高(r²=0.22)。反映物种多样性的三个指数总体上对P/B值的空间分异解释度最高(r²=0.37)。谱系多样性与次级生产力、P/B值的相关性相对较弱。生物多样性指数总体分别解释了次级生产力和群落稳定性中81.9%、54.8%的变异。上述研究结果表明,生物多样性与群落生产力、稳定性的关系可能因具体的生物群落而异。研究结果对于鄱阳湖湿地的底栖生物多样性保护有参考价值。     

生物多样性遥感研究方法浅议

概括了遥感在生物多样性研究方面的的优势及在各种尺度为生物多样性评价提供信息的能力;讨论了生物多样性信息系统应具备的功能和应包含的内容;分析了生物多样性遥感研究中数学模型与地理信息系统的耦合问题。     

Forest disturbance and recovery in Peruvian Amazonia

Amazonian forests function as biomass and biodiversity reservoirs, contributing to climate change mitigation. While they continuously experience disturbance, the effect that disturbances have on biomass and biodiversity over time has not yet been assessed at a large scale. Here, we evaluate the degree of recent forest disturbance in Peruvian Amazonia and the effects that disturbance, environmental conditions and human use have on biomass and biodiversity in disturbed forests. We integrate tree-level data on aboveground biomass (AGB) and species richness from 1840 forest plots from Peru's National Forest Inventory with remotely sensed monitoring of forest change dynamics, based on disturbances detected from Landsat-derived Normalized Difference Moisture Index time series. Our results show a clear negative effect of disturbance intensity tree species richness. This effect was also observed on AGB and species richness recovery values towards undisturbed levels, as well as on the recovery of species composition towards undisturbed levels. Time since disturbance had a larger effect on AGB than on species richness. While time since disturbance has a positive effect on AGB, unexpectedly we found a small negative effect of time since disturbance on species richness. We estimate that roughly 15% of Peruvian Amazonian forests have experienced disturbance at least once since 1984, and that, following disturbance, have been increasing in AGB at a rate of 4.7 Mg ha⁻¹ year⁻¹ during the first 20 years. Furthermore, the positive effect of surrounding forest cover was evident for both AGB and its recovery towards undisturbed levels, as well as for species richness. There was a negative effect of forest accessibility on the recovery of species composition towards undisturbed levels. Moving forward, we recommend that forest-based climate change mitigation endeavours consider forest disturbance through the integration of forest inventory data with remote sensing methods.     

Can we detect oceanic biodiversity hotspots from space?

Understanding the variability of marine biodiversity is a central issue in microbiology. Current observational programs are based on in situ studies, but their implementation at the global scale is particularly challenging, owing to the ocean extent, its temporal variability and the heterogeneity of the data sources on which compilations are built. Here, we explore the possibility of identifying phytoplanktonic biodiversity hotspots from satellite. We define a Shannon entropy index based on patchiness in ocean color bio-optical anomalies. This index provides a high resolution (1 degree) global coverage. It shows a relation to temperature and mid-latitude maxima in accordance with those previously evidenced in microbiological biodiversity model and observational studies. Regional maxima are in remarkable agreement with several known biodiversity hotspots for plankton organisms and even for higher levels of the marine trophic chain, as well as with some in situ planktonic biodiversity estimates (from Atlantic Meridional Transect cruise). These results encourage to explore marine biodiversity with a coordinated effort of the molecular, ecological and remote sensing communities.     

施氮时期对高产夏玉米氮代谢关键酶活性及抗氧化特性的影响

选用玉米品种登海661和郑单958为材料,研究了高产条件下施氮时期对夏玉米产量、氮素利用率、氮代谢相关酶及抗氧化酶活性的影响.结果表明： 拔节期一次性施氮不利于夏玉米产量提高和氮素积累,分次施氮且增施花粒肥显著提高了植株和籽粒的吸氮量,并提高了籽粒产量.拔节期、10叶期、花后10 d按2∶4∶4施氮,登海661产量最高可达14123.0 kg·hm^-2;基肥、拔节期、10叶期、花后10 d按1∶2∶5∶2施氮,郑单958产量最高可达14517.1 kg·hm^-2,这2种施氮方式较拔节期一次性施氮分别增产14.5%和17.5%.花前分次施氮可以显著提高开花期硝酸还原酶活性;登海661和郑单958在花后0~42 d中,施氮处理的谷氨酰胺合成酶、谷氨酸合成酶、谷氨酸脱氢酶活性分别平均提高了32.6%、47.1%、50.4%和145%、61.8%、25.6%,减缓了其下降趋势;超氧化物歧化酶、过氧化氢酶活性提高了22.0%、36.6%和13.4%、62.0%,丙二醛含量显著降低.在高产条件下,分次施氮且适当增加花粒肥施入比例可以提高氮代谢相关酶活性,延缓植株衰老,促进氮素吸收利用,进而提高籽粒产量.     

Hyperspectral modeling of ecological indicators – A new approach for monitoring former military training areas

Military areas are valuable habitats and refuges for rare and endangered plants and animals. We developed a new approach applying innovative methods of hyperspectral remote sensing to bridge the existing gap between remote sensing technology and the demands of the nature conservation community. Remote sensing has already proven to be a valuable monitoring instrument. However, the approaches lack the consideration of the demands of applied nature conservation which includes the legal demands of the EU Habitat Directive. Following the idea of the Vital Signs Monitoring in the USA, we identified a subset of the highest priority monitoring indicators for our study area. We analyzed continuous spectral response curves and tested the measurability of N = 19 indicators on the basis of complexity levels aggregated from extensive vegetation assemblages. The spectral differentiability for the floristic as well as faunistic indicators revealed values up to 100% accuracy. We point out difficulties when it comes to distinguishing faunistic habitat requirements of several species adapted to dry open landscapes, which in this case results in Overall accuracy of 67, 87–95, and 35% in the error matrix. In summary, we provide an applicable and feasible method to facilitating monitoring military areas by hyperspectral remote sensing in the following.     

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。     

A Biodiversity Indicators Dashboard: Addressing Challenges to Monitoring Progress towards the Aichi Biodiversity Targets Using Disaggregated Global Data

Recognizing the imperiled status of biodiversity and its benefit to human well-being, the world''s governments committed in 2010 to take effective and urgent action to halt biodiversity loss through the Convention on Biological Diversity''s “Aichi Targets”. These targets, and many conservation programs, require monitoring to assess progress toward specific goals. However, comprehensive and easily understood information on biodiversity trends at appropriate spatial scales is often not available to the policy makers, managers, and scientists who require it. We surveyed conservation stakeholders in three geographically diverse regions of critical biodiversity concern (the Tropical Andes, the African Great Lakes, and the Greater Mekong) and found high demand for biodiversity indicator information but uneven availability. To begin to address this need, we present a biodiversity “dashboard” – a visualization of biodiversity indicators designed to enable tracking of biodiversity and conservation performance data in a clear, user-friendly format. This builds on previous, more conceptual, indicator work to create an operationalized online interface communicating multiple indicators at multiple spatial scales. We structured this dashboard around the Pressure-State-Response-Benefit framework, selecting four indicators to measure pressure on biodiversity (deforestation rate), state of species (Red List Index), conservation response (protection of key biodiversity areas), and benefits to human populations (freshwater provision). Disaggregating global data, we present dashboard maps and graphics for the three regions surveyed and their component countries. These visualizations provide charts showing regional and national trends and lay the foundation for a web-enabled, interactive biodiversity indicators dashboard. This new tool can help track progress toward the Aichi Targets, support national monitoring and reporting, and inform outcome-based policy-making for the protection of natural resources.