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Seed size-and density-related hidden treatments in common biodiversity experiments

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Journal of Plant Ecology 2011年第3期4卷 132-137页

作者： Qinfeng Guo usda forest Service Eastern Forest Environmental Threat Assessment Center200 WT Weaver BoulevardAshevilleNC 28804USA

Aims With a few exceptions,most well-known field biodiversity experiments on ecosystem functioning have been conducted in plant communities(especially grasslands)in which different numbers of species are planted as *** these experiments,investigators have either kept the total seed weight or seed number constant across treatment ***,although in some cases attempts have been made to randomly choose species for planting from a designated species pool,the issue of possible‘hidden treatments’remains ***,the total and relative abundance among species and across treatments could still affect the *** study aims to determine whether treatments related to planted seed abundance and seed size may contribute to observed *** We re-analyzed data from four biodiversity experiments based on a common seeding design(*** treatments).Important Findings We show that diversity(richness)treatments usually involve a hidden treatment related to the planted seeds(***,number and seed size)that ultimately affect plant ***,the un-intended hidden treatment of seeding more seeds on more diverse plots contributes to the productivity to some *** derivative but often neglected hidden treatments are important for further improvement of experimental design and have significant implications in ecological restoration.

关键词： experimental design productivity restoration seed number seed weight

environmental remediation promotes the restoration of biodiversity in the Shenzhen Bay Estuary,South China

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Ecosystem Health and Sustainability 2022年第1期8卷 26-34页

作者： Hualin Xu Ke Liu Tianzhu Ning Gu Huang Qianmei Zhang Yuelin Li Mengqi Wang Yiming Fan Weili an Lingbo Ji Qinfeng Guo Hai Ren Neilingding-Futian National Nature Reserve Administration Bureau of Guangdong ShenzhenChina Department of Ecology South China Botanical GardenChinese Academy of SciencesGuangzhouChina University of Chinese Academy of Sciences BeijingChina CSCEC Aecom Consultans Co. Ltd Shenzhen BranchShenzhenChina Core Botanical Gardens Chinese Academy of SciencesGuangzhouChina School of Physics and Optoelectronic Engineering Foshan UniversityFoshanChina Zhongkai College of Agricultural Technology GuangzhouChina eastern forest environmental threat assessment center USDA Forest ServiceRTPNCUSA

Background:Rapid urbanization has greatly changed land-use patterns in many estuarine areas around the world,including the Guangdong-Hong Kong-Macao Greater Bay Area(GBA)resulting in serious water pollution and ecosystem *** City has conducted comprehensive ecological management and restoration in the Shenzhen Bay since *** natural vegetation consisting of mangroves,semi-mangroves,wetland plants,and terrestrial plants were restored from the bund to the inner bank of the Fengtang *** and sewage flow diversion systems were *** non-point source and point-source sewage are now treated in municipal sewage treatment plants,then naturally flow through the constructed wetland,and then through a natural wetland,restored natural embankment,and finally through mangrove communities substantially improving water ***:The restoration of the wetland has increased animal and microbial diversity and has supported the establishment of a complex and stable food *** water purification and habitat restoration,the number of alien invasive plants in the estuarine ecosystem has decreased,and the diversity of native species of birds,fish,macrobenthos,amphibians,and reptiles has ***:These improvements indicate that human beings and nature can coexist in support of the sustainable development of Shenzhen City.

关键词： Coastal city sewage treatment ecological restoration mangrove bird diversity

Improving forest burn severity estimations with partial least squares regression and orthogonal signal correction methods in Daxing'an Mountains,China

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Journal of forestry Research 2021年第3期32卷 1157-1165页

作者： Cunyong Ju Tijiu Cai Wenhong Li Ge Sun Chengliang Lei Xueying Di Xiuling Man School of forestry Northeast Forestry UniversityHarbin 150040People’s Republic of China Key Laboratory of Sustainable forest Ecosystem Management-Ministry of Education Northeast Forestry UniversityHarbin 150040People’s Republic of China Earth and Ocean Sciences Nicholas SchoolDuke UniversityDurham 27708USA eastern forest environmental threat assessment center Southern Research StationUSDA Forest ServiceRaleigh 27606USA Endangered Species Import and Export Management center State Forestry AdministrationBeijing 100714People’s Republic of China

Several indices and simple empirical models and ratios of single band from pre-and post-fire Landsat images have been developed to estimate and/or map burn ***,these models and indices are usually site-,time-and vegetation-dependent and their applications are *** Daxing'an Mountains range has the largest forested area in China and is prone to *** or not the existing models can effectively characterize the burn severity over a large region is *** this study,we used the orthogonal signal correction method based on partial least squares regression(PLSR)to select those variables that better interpret the variance of burn severity.A new index and other commonly used indices were used to construct a new,multivariate PLSR model which was compared with the popular single variable models,according to three assessment indices:relative root mean square error(RMSE%),relative bias(R E%)and Nash–Sutcliffe efficiency(NSE%).The results indicate that the multivariate PLSR model performed better than the other single variable models with higher NSE%(68.2%vs.67.8%)and less RE%(3.7%vs.-8.7%),while achieving almost the same R MSE%.We also discuss the spectral characteristics of the four selected variables for constructing the multivariate PLSR model and their correlation with the field burn severity *** new model developed from this study should help to better understand the patterns of forest burn severity and assist in vegetation restoration efforts in the region.

关键词： Satellite data Normalized burn ratio Variable selection Multiple regression

Ecohydrological processes and ecosystem services in the Anthropocene: a review

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Ecological Processes 2017年第1期6卷 364-372页

作者： Ge Sun Dennis Hallema Heidi Asbjornsen eastern forest environmental threat assessment center Southern Research StationU.S.Department of Agriculture Forest Service920 Main Campus Dr.Suite 300RaleighNC 27606USA Oak Ridge Institute for Science and Education U.S.Department of EnergyOak RidgeTN 37830USA Institute for the Study of Earth Oceansand SpaceUniversity of New HampshireDurhamNHUSA

The framework for ecosystem services has been increasingly used in integrated watershed ecosystem management practices that involve scientists,engineers,managers,and policy *** objective of this review is to explore the intimate connections between ecohydrological processes and water-related ecosystem services in human-dominated ecosystems in the *** synthesize current literature to illustrate the importance of understanding the ecohydrological processes for accurately quantifying ecosystem services under different environmental and socioeconomic settings and *** synthesis focuses on managed ecosystems that are dominated by humans and explores how ecological processes affect the tradeoffs and synergies of multiple ecosystem *** identify research gaps in studying ecological processes mainly including energy,carbon,water,and nutrient balances to better assess and quantify ecosystem services that are critical for sustaining natural resources for future *** better assess ecosystem services,future ecohydrological studies need to better account for the scaling effects of natural and anthropogenic stressors exerted on evapotranspiration and other water supply and demand *** studies should focus on the bidirectional interactions between hydrological functions and services and human actions to solve real world problems such as water shortages,ecological degradation,and climate change adaptation.

关键词： watershed services ecosystem

秦淮河流域土地利用/覆被变化对蒸散量变化的贡献

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中国农业气象 2019年第5期40卷 269-283页

作者：秦孟晟郝璐郑箐舟金楷仑孙阁南京信息工程大学江苏省农业气象重点实验室南京210044 eastern forest environmental threat assessment center Southern Research StationUSDA Forest ServiceResearch Triangle Park

为评估城市化造成的土地利用/覆被类型变化(Land use/cover change,LUCC)对流域尺度蒸散量变化的影响,选取长三角地区秦淮河流域为研究区,基于Landsat系列卫星数据和站点气象数据,构建决策树模型,提取2000年和2013年土地利用/覆被类型数... 详细信息

为评估城市化造成的土地利用/覆被类型变化(Land use/cover change,LUCC)对流域尺度蒸散量变化的影响,选取长三角地区秦淮河流域为研究区,基于Landsat系列卫星数据和站点气象数据,构建决策树模型,提取2000年和2013年土地利用/覆被类型数据,同时借助SEBAL模型估算研究区四季典型日(春季:2014-05-26、夏季:2013-08-11、秋季:2013-10-14、冬季:2014-01-02)栅格尺度蒸散,探讨2000-2013年秦淮河流域主要土地利用/覆被类型间转化过程对流域尺度日蒸散量变化的贡献。结果表明:(1)相较于2000年,2013年秦淮河流域不透水面增加183.8%,而水稻田、旱地、林地和水域分别减少19.1%、10.7%、12.8%和9.5%。2000-2013年主要土地利用/覆被类型转化方向包括水稻田→不透水面、旱地→不透水面、水稻田→旱地和旱地→水稻田,转化面积分别为208、168、282和232km^2;(2)仅考虑LUCC的影响,对比2000年,2013年研究区流域尺度日蒸散总量在四季典型日分别减少134万、109万、60万和5万m^3。在春、夏、秋三季典型日,水稻田和旱地向不透水面转化过程造成的贡献率分别为-58.5%、-59.5%、-54.4%和-35.1%、-36.3%、-39.8%,负贡献会抵消旱地向水稻田转化过程造成的正贡献(分别为16.8%、16.3%、5.7%),导致春、夏、秋三季典型日流域尺度日蒸散量下降;而在冬季典型日,水稻田向不透水面、旱地向不透水面和水稻田向旱地转化过程造成的负贡献(分别为-48.8%、-20.5%和-31.8%)会抵消旱地向水稻田转化过程造成的正贡献(26.1%),导致冬季典型日流域尺度日蒸散量下降。总体而言,2000-2013年秦淮河流域城市化带来土地利用/覆被的显著变化,使蒸散较高的水稻田和旱地向蒸散较低的不透水面大面积转化,导致流域尺度日蒸散量在四季均呈下降趋势。

关键词：蒸散 SEBAL模型土地利用/覆被变化秦淮河流域 Landsat卫星影像

Modeling the impacts of climate variability and hurricane on carbon sequestration in a coastal forested wetland in South Carolina

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Natural Science 2013年第3期5卷 375-388页

作者： Zhaohua Dai Carl C. Trettin Changsheng Li Ge Sun Devendra M. Amatya Harbin Li center for forested Wetland Research USDA Forest Service Cordesville USA Earth Science Research center EOS University of New Hampshire Durham US Earth Science Research center EOS University of New Hampshire Durham USA eastern forest environmental threat assessment center Southern Research Station USDA Forest Service Raleigh USA

The impacts of hurricane disturbance and climate variability on carbon dynamics in a coastal forested wetland in South Carolina of USA were simulated using the forest-DNDC model with a spatially explicit approach. The model was validated using the measured biomass before and after Hurricane Hugo and the biomass inventories in 2006 and 2007, showed that the forest- DNDC model was applicable for estimating carbon dynamics with hurricane disturbance. The simulated results indicated that Hurricane Hugo in 1989 substantially influenced carbon storage immediately after the disturbance event. The simulated net ecosystem exchange (NEE) for the 58-year period (1950-2007) indicated that the hurricane reduced CO2 sequestration due primarily to the increased decomposition of a large amount of litter and woody debris, including fallen trees (over 80% of pre-hurricane trees), debris and branches, and dead roots. The inter-annual fluctuation of soil CO2 flux showed that the climate variability interfered substantially soil carbon dynamics in the forest. The results showed that there were substantial spatial and temporal differences in CO2 flux (3.2 - 4.8 Mg·C·ha–1) and wood biomass due to the differences in physical and biogeochemical characteristics in the forest.

关键词： Greenhouse Gas forest-DNDC Biogeochemical Model Biomass Climate Change

Surface storm flow prediction on hillslopes based on topography and hydrologic connectivity

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Ecological Processes 2016年第1期5卷 153-165页

作者： Dennis W.Hallema Roger Moussa Ge Sun Steven G.McNulty INRA UMR LISAH Laboratoire d’etude des Interactions Sol-Agrosysteme-Hydrosysteme(INRAIRDMontpellier SupAgro)2 place Pierre Viala34060 Montpellier CEDEX 2France U.S.Department of Agriculture forest Service Eastern Forest Environmental Threat Assessment CenterSouthern Research StationRaleighNC 27606USA U.S.Department of Energy Oak Ridge Institute for Science and EducationOak RidgeTN 37830USA

Background:Hillslopes provide critical watershed ecosystem services such as soil erosion control and storm flow regulation through collecting,storing,and releasing rain *** intense rainstorms,rainfall intensity and infiltration capacity on the hillslope control Hortonian runoff while the topographic attributes of the hillslope(e.g.,slope,aspect,curvature)and the channel network define the structural hydraulic connectivity that determines how rapidly excess water is *** paper discusses literature on the link between topographic attributes and hydrologic connectivity and demonstrates how this link can be used to define a parsimonious model for predicting surface runoff during high intensity *** text:First,we provide a topographic characterization of the hillslope necessary to determine the structural hydrologic connectivity of surface flow based on existing ***,we demonstrate a hydrologic surface response model that routes the geomorphologic unit hydrograph(GIUH)through a spatial domain of representative elementary hillslopes reflecting the structural hydrologic *** attributes impact flow and travel time distributions by affecting gravitational acceleration of overland flow and channel,solar irradiance,flow deceleration by vegetation,and flow divergence/***:We show with an example where we apply the GIUH-based model to hypothetical hillslopes that the spatial organization of the channel network is critical in the flow and travel time distribution,and that topographic attributes are key in obtaining simple yet accurate representations of hydrologic *** GIUH models of surface runoff that use this hydrologic connectivity have the advantage of low data requirements,being scalable and applicable regardless of the spatial complexity of the hillslope,and have the potential to fundamentally improve flood forecasting tools used in the assessment of ecosystem servi

关键词： Hydrological processes Hydrologic connectivity Storm flow Ecosystem services GIUH

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变化环境下流域水-碳平衡演化研究综述

水利学报 2021年第3期52卷 300-309页

作者：段凯孙阁刘宁中山大学土木工程学院广东广州510275 南方海洋科学与工程广东省实验室(珠海) 广东珠海519082 eastern forest environmental threat assessment center USDA Forest ServiceResearch Triangle ParkNC 27709

流域水量平衡与碳平衡通过植物光合作用与蒸散发过程紧密相联。在全球环境变化的背景下,研究流域水-碳平衡的耦合关系与对变化环境的响应规律对于发展生态水文科学具有重要科学意义,也可为区域水安全保障、生态系统服务功能评价、气候... 详细信息

流域水量平衡与碳平衡通过植物光合作用与蒸散发过程紧密相联。在全球环境变化的背景下,研究流域水-碳平衡的耦合关系与对变化环境的响应规律对于发展生态水文科学具有重要科学意义,也可为区域水安全保障、生态系统服务功能评价、气候变化适应性对策制定等提供科学支撑。本文从水循环与碳循环要素的监测、水-碳耦合关系的量化和模拟、变化环境对水-碳平衡的干扰、流域尺度上水-碳平衡演化规律识别与归因等方面对相关研究进展进行综述,探讨当前的研究热点、面临的问题与挑战、以及未来的发展趋势。

关键词：水-碳耦合流域水-碳平衡变化环境研究进展

Pandemic spotlight on urban water quality

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Ecological Processes 2020年第1期9卷 249-251页

作者： Dennis W.Hallema François-Nicolas Robinne Steven G.McNulty Department of forestry and environmental Resources North Carolina State University3041 East Cornwallis RoadResearch Triangle ParkNC 27709USA Canadian Partnership for Wildland Fire Science Department of Renewable ResourcesUniversity of Alberta751 General Services BuildingEdmontonAB T6G 2H1Canada eastern forest environmental threat assessment center Southern Research StationU.S.Department of Agriculture Forest ServiceResearch Triangle ParkNC 27709USA.

Surface water improvements associated with the COVID-19 economic slowdown illustrate environmental resiliency and societal control over urban water quality.

关键词： urban quality. water