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Mapping species assemblages of tropical forests at different hierarchical levels based on multivariate regression trees

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Forest ecosystems 2023年第3期10卷 387-397页

作者： Qi Yang Maaike Y.Bader Guang Feng Jialing Li Dexu Zhang Wenxing Long Wuzhishan national Long Term Forest ecosystem research Station College of ForestryHainan UniversityHaikou570228China Ecological Plant Geography Faculty of GeographyUniversity of MarburgDeutschhausstrasse 1035032MarburgGermany Wuzhishan division of Hainan Tropical Rainforest national Park Bureau Wuzhishan572200China

Background: Vegetation distribution maps are of great significance for nature protection and management. In diverse tropical forests, accurate spatial mapping of vegetation types is challenging;the high species diversity and abundance of rare species challenge classification concepts, while remote sensing signals may not vary systematically with species composition, complicating the technical capability for delineating vegetation types in the ***: We used a combination of field-based compositional data and their relations to environmental variables to predict the distribution of forest types in the Wuzhishan national Natural Reserve(WNNR), Hainan Island,China, using multivariate regression trees(MRT). The MRT was based on arboreal vegetation composition in 132plots of 20 m×20 m with a regular spacing of 1 km. Apart from the MRT, non-metric multidimensional scaling(NMDS) was used to evaluate vegetation-environment ***: The MRT model worked best when using 14 key environmental variables including topography, climate,latitude and soil, although the difference with the simpler model including only topographical variables was small. The full model classified the 132 plots into 3 vegetation types, 6 formation groups, 20 formations and 65associations at different hierarchical syntaxonomic levels. This model was the basis for forest vegetation maps for the WNNR. MRT and NMDS showed that elevation was the main driving force for the distribution of vegetation types and formation groups. Climate, latitude, and soil(especially available P), together with topographic variables, all influenced the distribution of formations and ***: While elevation determines forest-type distributions, lower-level syntaxonomic forest classes respond to the topographic diversity typical for mountains. Apart from providing the first detailed forest vegetation map for any part of WNNR, we show how, in spite of limitations, MRT with existing enviro

关键词： Species assemblages Tropical forest Mapping Multivariate regression trees Non-metric multidimensional scaling

Using radium isotopes to evaluate the uncertainty of submarine groundwater discharge in the northeast and entirety of Daya Bay

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海洋学报:英文版 2023年第8期42卷 24-31页

作者： Hequan Gu Feng Zhao Zhixin Ni Meigui Wu Li Zhao Aicui Dang Dongmei Li Minxia Zhang Qin Hu South China Sea Environment Monitoring Center State Oceanic AdministrationGuangzhou 510300China Nansha Islands Coral Reef ecosystem national Observation and research Station Guangzhou 510300China Key Laboratory of Marine Environmental survey Technology and Application Ministry of Natural ResourcesGuangzhou 510300China CNOOC research Institute Co. Ltd.Beijing 100028China

Submarine groundwater discharge(SGD),which can be traced using naturally occurring radium isotopes,has been recognized as a significant nutrient source and land-ocean interaction passage for the coastal waters of the Daya Bay,***,uncertainties in assessing SGD fluxes must still be discussed in *** this study,we attempted to utilize the Monte Carlo method to evaluate the uncertainties of radium-derived SGD flux in the northeast and entirety of the Daya *** results show that the uncertainties of the SGD estimate in the northeast bay are very sensitive to variations in excess radium inventories as well as radium inputs from bottom sediments,while the uncertainties of the SGD estimate for the entire bay are strongly affected by fluctuations in radium inputs from bottom sediments and radium end-members of *** study will help to distinguish the key factors controlling the accuracy of SGD estimates in similar coastal waters.

关键词： submarine groundwater discharge(SGD) radium isotopes Monte-Carlo method Daya Bay uncertainty analysis

Beyond city expansion:multi-scale environmental impacts of urban megaregion formation in China

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national Science Review 2022年第1期9卷 79-91页

作者： Weiqi Zhou Wenjuan Yu Yuguo Qian Lijian Han Steward T.A.Pickett Jing Wang Weifeng Li Zhiyun Ouyang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences Cary Institute of ecosystem Studies Beijing Urban ecosystem research Station Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Environmental degradation caused by rapid urbanization is a pressing global ***,little is known about how urban changes operate and affect environments across multiple *** on China,we found urbanization was indeed massive from 2000 to 2015,but it was also very uneven,exhibiting high internal city *** areas in China as a whole became less green,warmer,and had exacerbated PM2.5 ***,environmental impacts differed in newly developed versus older areas of *** impacts were prominent in newly urbanized areas,while old urban areas generally showed improved environmental *** addition,regional environmental issues are emerging as cities expand,connect and interact to form urban *** turn urbanization into an opportunity for,rather than an obstacle to,sustainable development,we must move beyond documenting urban expansion to understand the environmental consequences of both internal city dynamics and the formation of urban megaregions.

关键词： urbanization urban and regional sustainability landscape change air pollution urban heat island

Physiological Basis of Stagnant Flooding Tolerance in Rice

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Rice science 2017年第2期24卷 73-84页

作者： Sandhya R.KUANAR Anuprita RAY Santosh K.SETHI Krishnendu CHATTOPADHYAY Ramani K.SARKAR Crop Physiology&Biochemistry division National Rice Research InstituteCuttack 753006India

Stagnant flooding(SF) is an important constraint which prolonges partial submergence damages of rice plants and reduces grain yield. Due to the heterogeneity in flood-prone ecosystem, many different types of traditional rice varieties are being grown by the farmers. The local landraces adapted to extreme in water availability could be the sources of new gene(s) which would be utilized to improve the adaptability of rice to SF with high yield. The main goal of this study is to identify new genetic resources tolerant to SF based on morpho-physiological traits. A total of 16 rice varieties were selected after initial screening from more than 400 rice varieties which were collected from eastern states of India. The increase rate of plant height was higher under SF compared to control, whereas no such trend was observed in the increment rate of aboveground total dry weight and culm dry weight. Area of aerenchyma gas spaces per tiller increased whereas root oxidase activity decreased under SF. The reduction of root oxidase activity, leaf area, and leaf dry weight was higher in susceptible varieties under SF compared to control. Stability index for different grain yield and yield attributes revealed that the impact of SF differed among different varieties. Correlation coefficient studies among different parameters taking stability index showed significant association with the grain yield. Based on the findings, it was concluded that maintenance of equivalent panicle weight and panicle number, plant height and harvest index at the maturity stage, leaf area, leaf and culm dry weights, root oxidase activity and tiller numbers at the flowering stage under SF compared to control help the plant to counteract the adverse effects of SF.

关键词： morpho-physiological trait rice stagnant flooding yield

Litterfall production and nutrient return in different-aged Chinese fir(Cunninghamia lanceolata) plantations in South China

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Journal of Forestry research 2015年第1期26卷 79-89页

作者： Lili Zhou Addo-Danso Daniel Shalom Pengfei Wu Shubin Li Yayun Jia Xiangqing Ma Forestry College Fujian Agriculture and Forestry University Chinese fir Engineering Technology research Center of the State Forestry Administration Faculty of Forestry University of British Columbia ecosystem Services and Climate Change division CSIR-Forestry Research Institute of Ghana

The amounts of litter produced and nutrients returned play a fundamental role in the productivity and biogeochemical and nutrient cycling of forest *** monitored annual litterfall production, nutrient return,and monthly dynamics over a one-year period in Chinese fir plantations aged 10, 22, and 34 years. Our objective was to quantify litterfall and nutrient return over a complete harvest rotation of Chinese fir. Annual litterfall production increased with stand age and was recorded as（3,294.6 ± 360.4）,（3,733.9 ± 211.2）, and（4,876.1 ± 212.8） kg ha-1a-1in stands aged 10, 22 and 34 years, respectively. Total litter production was significantly greater in the stand aged34 years than in the stand aged 10 years（p ／ 0.05）. With the exception of miscellaneous components, needle litterfall constituted the highest proportion（27.5–43.6 %）, followed by branches/twigs（9.5–16.6 %）. In all three plantations,annual total nutrient return to soil was in the order of C（1,119.95–2,709.05 kg ha-1a-1） [ N（39.32–62.04 kg ha-1a-1） [ K（15.95–22.44 kg ha-1a-1） [ P（1.30–1.63 kg ha-1a-1）. C, N, K and P input to soil was significantly lower in the 10-year-old stand in comparison to the 22- and34-year-old stands（p ／ 0.05）. Litterfall production and nutrient return（C, N and K） followed similar patterns, and C and N input to soil was significantly related to litterfall production（needle, branch and total litterfall）. C, N, P and K input to soil and total litterfall production were mainly driven by needle litterfall.

关键词： Cunninghamia lanceolata Litterfall production Nutrient return

Pitfalls in interpretation of shallow seismic data

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Applied Geophysics 2012年第1期9卷 87-94,117页

作者： Ahmed Ismail Edward Smith Andrew Phillips Andrew Stumpf Illinois State Geological survey division University of Illinois Urbana-Champaign national research Institute of Astronomy and Geophysics

High-resolution shallow seismic methods are the most widely used geophysical methods in near surface characterization. However, in many cases interpreting the seismic images can be misleading. In this article, we present three case studies where results from P-wave seismic reflection, SH-wave seismic reflection, and multi-channel analysis of surface wave （MASW） surveys were incorrectly interpreted because of inadequate constraints on either the surveyed sites surface or subsurface conditions. A P-wave reflection survey feature was first interpreted as a shallow fault zone but it was later determined to result from a high level of background noise as the acquisition passed through a road intersection. A SH-wave seismic reflection survey feature was interpreted to be a reverse dip-slip fault but targeted drilling showed it was deep local erosion into the bedrock surface. Finally, in an MASW survey, a steeply dipping feature was first interpreted as a bedrock valley. However, later exploratory drilling showed the feature to be a shallow layer of very soft lake sediment that severely damped most of the applied surface wave frequency band. Although initial interpretations were incorrect, they stimulated discussions among geophysicists and geologists and underscored the need for meaningful cooperation and discourse between the scientists before, during, and after geophysical data acquisition.

关键词： Seismic reflection multi-channel analysis of surface wave interpretation pitfalls

Patients’experiences with‘sludge’(administrative burden)in the cancer screening process and its relationship with screening completion,experience and health system distrust

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Family Medicine and Community Health 2024年第S2期12卷 8-17页

作者： Michelle S Rockwell Brianna Chang Vivian Zagarese Jamie K Turner Ally Southworth YingXing Wu Paul Yeaton Li Li Jeffrey S Stein Sarah H Parker John W Epling Department of Family and Community Medicine Virginia Tech Carilion School of MedicineRoanokeVirginiaUSA Department of Family and Community Medicine Carilion ClinicRoanokeVirginiaUSA Virginia Tech Carilion School of Medicine RoanokeVirginiaUSA Department of Health Systems and Implementation Science Virginia Tech Carilion School of MedicineRoanokeVirginiaUSA Graduate Program in Translational Biology Medicineand HealthVirginia TechRoanokeVirginiaUSA Health Analytics research Team Carilion ClinicRoanokeVirginiaUSA division of Gastroenterology Department of Internal MedicineCarilion ClinicRoanokeVirginiaUSA Department of Family Medicine University of Virginia School of MedicineCharlottesvilleVirginiaUSA Center for Health Behaviors research Fralin Biomedical Research Institute at VTCRoanokeVirginiaUSA

Objective‘Sludge’refers to administrative burdens or frictions that preclude people from getting what they want or need(eg,duplicative forms,complicated instructions,long waiting times).This mixed methods study evaluated patients’perceptions of sludge in the colorectal cancer(CRC)screening process and some impacts of this *** We employed an exploratory sequential mixed methods study design that comprised patient interviews and a patient *** interviews informed final survey revisions and captured contextual data about patients’experiences with *** transcripts were inductively and deductively analysed to identify overarching *** survey quantified sludge,delayed or forgone screenings,screening experience(Net Promoter Score)and health system distrust(Health System Distrust Scale).We usedχ2 or t-tests for univariable comparisons and logistic or linear regressions to evaluate the association between cumulative sludge score and delayed or forgone screenings,screening experience and health system *** were integrated for *** Southeastern United *** Patients who were 45–75 years of age,at average risk for CRC and had either completed or been referred for CRC screening(colonoscopy or stool-based test)within the previous 12 *** 22 interview participants and 255 survey participants completed the study.38(15%)survey participants rated their screening experience as poor(Net Promoter Score=0–7 out of 10).The mean(SD)Health System Distrust Scale score was 22.4(6.3)out of 45 possible points(higher score=greater distrust).Perceptions of sludge in the CRC screening process varied,with long waiting times and burdensome communication being the most common sources(58%and 35%of participants,respectively).Sludge was positively associated with delayed or forgone screenings(OR=1.42,95%CI 1.28,1.57,p<0.001),poor screening experience(OR=1.15,95%CI 1.04,1.28,p=0.009)and health system distrust(β=0.47,p

关键词： sludge screening burden

A New Theory on the Origin of Fusain

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地质学报 1938年第2期 191-196页

作者： C.C.HSIAO Fuel research division of the Chemical Laboratory national Geological survey of China

The occurrence of fusain in practically all the coal deposits and itsdistinctly different properties as compared with those of other constituentsof coal have stimulated many speculations in regard to its mode *** vari... 详细信息

关键词： Th A New Theory on the Origin of Fusain

Litter removal impacts on soil biodiversity and eucalypt plantation development in the seasonal tropics

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Journal of Forestry research 2023年第3期34卷 735-748页

作者： Jonas Inkotte Barbara Bomfim Sarah Camelo da Silva Marco Bruno Xavier Valadão Márcio Gonçalves da Rosa Roberta Batista Viana Alcides Gatto Reginaldo SPereira Department of Forestry Engineering University of BrasiliaBrasíliaDistrito FederalBrazil Climate and ecosystem Sciences division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA SESI/SENAI Social Service Industry Santa Catarina StateChapecóBrazil

The little layer of tree plantations provides primary nutrients for uptake,buff ers changes in soil moisture,and provides habitat and substrate to soil epigeic ***,this layer in eucalypt plantations is often removed to reduce fuel load during the fi re season in the Brazilian savanna(Cerrado).Therefore,it is necessary to quantify the eff ects of changes in litter dynamics on the function of these plantations,on key nutrient cycling processes and on epigeic fauna diversity and *** two adjacent stands(one juvenile and one mature),the consequences of two years of litter removal were quantifi ed as monthly litterfall,leaf and fi ne wood litter decomposition,epigeic fauna abundance and diversity,soil biogeochemical variables,and tree diameter and basal area *** litterfall rates in juvenile and mature stands did not change with litter removal over the study *** litterfall ranged from 4.1 to 4.9 Mg ha^(−1)a^(−1)in litter removal plots and from 3.9 to 4.8 Mg ha^(−1)a^(−1)in control *** wood litter decomposition was slower in litter removal plots compared to controls,while leaf decomposition rates were similar in *** years of litter removal in the juvenile stand did not aff ect topsoil biogeochemical parameters but decreased available phosphorus at 20–40 cm depth relative to *** the mature stand,total cation exchange capacity(0–20 cm)was higher in controls(6.4 cmol c dm^(−3))relative to litter removal plots(6.3 cmol c dm^(−3)),while soil moisture(0–40 cm depth)was lower in litter removal(25.45 m 3 m^(−3))compared to control plots(26 m^(3)m^(−3))in the dry season.A non-metric multidimensional scaling ordination revealed an increased homogeneity in epigeic fauna where litter was ***,decomposition,diameter increment,four soil physical parameters and fourteen chemical parameters at 0–20 and 20–40 cm depth explained the diff erences in soil epigeic fauna composition between litter removal and control p

关键词： Cerrado Nutrient cycling Soil ecology Soil epigeic fauna Plantation management