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Management breaks the natural productivity-biodiversity relationship in forests and grassland： an opinion

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Forest Ecosystems 2018年第1期5卷 28-35页

作者： e.d.schulze o.bouriaud u.weber c.roscher d.hessenmoeller f.kroiher p.schall mpi biogeochemistry Box 10016407701 JenaGermany national forest inventory national research and development institute for forestry incdsErolor Bd 128VoluntariRomania and University stefan cel Mare of Suceava13 Universitatl Str.720229 SuceavaRomanla ufz hemholtz centre for environmental researchphysiological diversityDiversityPermoserstr 1504318 Lelpzig Germany forstamt schmalkalden thueringen forstSchlossberg 1198574 Schmalkalden Germany thünen-institut für waldokosysteme Adolf Moller Str 11 6225 EberswaldeGermany department silviculture and forest ecology of the temperate zones university of gottingenD 37077 GOttingenGermany

Background： Two approaches mark the difference between the ＂ecological＂ and ＂agricultural＂ view of the biodiversity/ growth relation. In ecology the trend is averaged by taking monocultures of all species as baseline to evaluate mixtures. This contrasts the ＂agricultural＂ view focusing on the most productive species or species combination as baseline to evaluate mixtures. The present study investigates the change of highest rates （maximum） productivities in grasslands and forests with increasing plant （or tree） diversity, and compares these with the average response. Methods： We base our analysis on existing published datasets relating the growth of plant stands （growth rate per land area） to the diversity on the same plot. We use a global dataset （Ellis et al. 2012 and MODIS-data, see Fig. 1）, the grassland experiment in lena （Buchmann et al. 2017）, the regional study on forests in Romania and Germany by Bouriaud et al. （2016）, and data from the German National Forest inventory （BWl 3, see Fig. 3）. In all cases the average response of growth to changes in biodiversity as well as the boundary line of the maximum values was calculated. Results： in both vegetation types a decreasing trend of maximum productivity with any added species emerges, contrasting the average trend that was positive in grassland, but absent in forests. The trend of maximum values was non-significant in grasslands probably due to the fact that not all combinations of species mixtures were available. In temperate forests, maximum productivity decreases significantly by about 10% in regional studies and by 8% at national scale with each added species. Maximum biomass per area was the same for managed and unmanaged conditions. A global assessment of NPP and biodiversity could also not confirm a general positive biodiversity- productivity relationship. Conclusions： Managed grasslands and forests reach highest productivity and volumes at low diversity. Also globally we could not confirm a biodiversi

关键词： Biodiversity Productivity Maximum rates Land management forests Grasslands

Hurricane disturbances, tree diversity, and succession in North Carolina Piedmont forests, USA

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Journal of Forestry Research 2019年第1期30卷 219-231页

作者： Weimin Xi Robert K.Peet Michael T.Lee Dean L.Urban Department of Biology University of North Carolina at Chapel Hill Department of Biological and Health Sciences Texas A & M University-Kingsville The Nicholas School of the Environment Duke University

Windthrow plays a critical role in maintaining species diversity in temperate forests. Do large-scale strong wind events(i.e., tropical cyclones, including hurricanes,typhoons and severe cyclonic storms) increase tree diversity in severely damaged forest areas? Do hurricanes(tropical cyclones that occurs in the Atlantic Ocean and northeastern Pacific Ocean) lead to altered relative abundance of shade-tolerant and shade-intolerant species? Did historic hurricanes alter the succession trajectory of the damaged forests? We used nearly 70-year tree demographic data to assess the effects of two major hurricanes on woody species diversity in Piedmont forests, North Carolina, USA. Species richness(S) and Shannon–Wiener's diversity index(H') were used to evaluate the changes in tree diversity. The changes in composition were assessed with Nonmetric Multidimensional Scaling. The pre-hurricane successional phase can strongly influence both the damage severity and subsequent responses. Although there is often an immediate drop in diversity following a hurricane, understory tree diversity quickly increases to levels that exceed those prior to the disturbance. This leads to an increase in diversity in stands that were substantially damaged. Hurricanes significantly decrease the dominance of shade-intolerant canopy species while increasing preestablished, more shade-tolerant species. We conclude that large, and infrequent hurricanes help to maintain local tree diversity, but also accelerate the increase in dominance of understory species such as red maple and beech.

关键词： Wind disturbance Tree species diversity Plant succession Disturbance-diversity relationship Piedmont forests

Contrasting effects of nitrogen addition on litter decomposition in forests and grasslands in China

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Journal of Arid Land 2021年第7期13卷 717-729页

作者： SU Yuan MA Xiaofei GONG Yanming LI Kaihui HAN Wenxuan LIU Xuejun State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Bayanbulak Grassland Ecosystem Research Station Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesBayanbulak 841314China University of Chinese Academy of Sciences Beijing 100049China Chinese Academy of Sciences Research Center for Ecology and Environment of Central Asia Urumqi 830011China Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation College of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Nitrogen(N)addition has profound impacts on litter-mediated nutrient *** studies have reported different effects of N addition on litter decomposition,exhibiting positive,negative,or neutral *** meta-analysis of litter decomposition under N addition was mainly based on a small number of samples to allow comparisons among ecosystem *** study presents the results of a meta-analysis incorporating data from 53 published studies(including 617 observations)across forests,grasslands,wetlands,and croplands in China,to investigate how environmental and experimental factors impact the effects of N addition on litter *** across all of the studies,N addition significantly slows litter decomposition by 7.02%.Considering ecosystem types,N addition significantly accelerates litter decomposition by 3.70%and 11.22%in grasslands and wetlands,respectively,clearly inhibits litter decomposition by 14.53%in forests,and has no significant effects on litter decomposition in *** the accelerated litter decomposition rate in grasslands due to N addition,litter decomposition rate increases slightly with increasing rates of N ***,N addition slows litter decomposition in forests,but litter decomposition is at a significantly increasing rate with increasing amounts of N *** responses of litter decomposition to N addition are also influenced by the forms of N addition,experiential duration of N addition,humidity index,litter quality,and soil *** summary,N addition alters litter decomposition rate,but the direction and magnitude of the response are affected by the forms of N addition,the rate of N addition,ambient N deposition,experimental duration,and climate *** study highlights the contrasting effects of N addition on litter decomposition in forests and *** finding could be used in biogeochemical models to better evaluate ecosystem carbon cycling under increasing N deposition due to th

关键词： litter decomposition rate N addition ambient N deposition litter quality meta-analysis forests grasslands

A new sampling method in the Zagros forests using GIS(case study: Ilam forests of Iran)

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Journal of Forestry Research 2019年第6期30卷 2079-2085页

作者： A.Karamshahi Faculty of Agriculture Ilam University

One of the basic parameters in forest management planning is detailed knowledge of growing stock,information collected by forest *** methods must be accurate,inexpensive,and be easy to implement in the *** study presents a new sampling method called branching transect for use in the Iranian Zagros forests and similar *** of the new method include greater accuracy,easy implementation in nature,simplicity of statistical calculations,and low *** this method,transect is used,which includes some subtransects(side branches).The length of the main transect,side branches,number of trees measured in each side branch,and the number of sub-branches in this method are changeable based on homogeneity,heterogeneity,and density of a *** this study,based on the density and heterogeneity of the forest area studied,20-m transects with four and eight side branches were *** plots(Transects)in four inventory networks(100 m×100 m,100 m×150 m,150 m×150 m and 100 m×200 m)were implemented in the GIS *** results of this sampling method were compared to the results of total inventory(100%count)in terms of accuracy,precision(t-test),and inventory error *** transect results were statistially similar to total inventory counts in all *** results show that this method of estimating density and canopy per hectare can be used in Zagros forests and similar forests.

关键词： Branching transect Canopy Density Network Sampling methods Zagros forests

Simulating　sensitivities　of　Changbai　Mountain　forests　to　potential　climate　change

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Journal of Environmental Sciences 1996年第3期8卷 354-366页

作者： Yan Xiaodong Zhao Shidong (Institute of Applied Ecology. Chinese Academy of Sciences,Shenyang 110015, China) Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110015 China

Changbai Mt. forest in the northeastern China is both a very important timber resource of China and one of the most typical and less disturbed temperate mixed evergreen coniferous-deciduous forest in the *** this paper, NEWCOP. a gap class model of forest growth and succession was proposed to simulate the sensitivity of the forest in Changbai Mountain to elevate CO_2. warmer temperature and precipitation change. NEWCOP was tested on long term simulation behaviors and short term fitting ability to field data. About the response of forests of Changbai Mountain to possible climate change, NEWCOP suggested that forest landscape go up within long term and forest biomass comes down within short term because of dieback of forest trees.

关键词： gap model climate change forests China.

Diversity of root-associated fungi of Rhododendron simsii in subtropical forests: fungal communities with high resistance to anthropogenic disturbances

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Journal of Forestry Research 2019年第6期30卷 2321-2330页

作者： Yanhua Zhang Fangping Tang Jian Ni Lijia Dong Lifu Sun College of Life Sciences Shaoxing University

Species of the Ericaceae or heath family are widely distribute in continental ecosystems and their special ericoid mycorrhizas(ERM)are considered benefi cial to their survival and persistence in variable ***,increasing anthropogenic disturbances and improper forest management are aff ecting subtropical forests of China where these native species *** activities not only aff ect plant communities above-ground,but also impose pressures on microbial communities *** this study,rootassociated fungal communities of Rhododendron simsii in four forest types under diff erent anthropogenic disturbances were identifi ed using an Illumina Miseq platform,i.e.,old growth forests,secondary forests with one cutting(SECⅠ),secondary forests with two cuttings(SECⅡ),and Chinesefi r plantations(PLF).Intra-and inter-annual variations were analyzed by comparing samples taken in diff erent seasons and *** results show that:(1)over 1000 OTUs were found in hair roots with most from the division Ascomycota and Basidiomycota belonging to diff erent functional groups;(2)while there were a few indicator OTUs specifi c to diff erent forest types,seasons and years,the proportion of shared taxa was quite large,accounting for 44.9–79.4%of the total OTUs;(3)signifi cantly positive correlations were found between disturbance sensitivity and temporal variations in common fungal orders,and both in major fungal orders were signifi cantly diff erent among fungal functional groups in which putative and possible ERM fungi were highly resistant to disturbances and low temporal *** high disturbance resistance and temporal persistence of putative ERM fungi may be essential for the successful adaptation of *** in disturbed subtropical forests of China.

关键词： Rhododendron simsii Mycorrhiza Fungal community Diversity Subtropical forests Human disturbance

Interaction between climate and management on beta diversity components of vegetation in relation to soil properties in arid and semi-arid oak forests, Iran

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Journal of Arid Land 2019年第1期11卷 43-57页

作者： Heydari MEHDI Aazami FATEMEH Faramarzi MARZBAN Omidipour REZA Bazgir MASOUD Pothier DAVID Prévosto BERNARD Department of Forest Science College of Agriculture Ilam University Department of Rangeland and Watershed Management College of Agriculture Ilam University Department of Rangeland and Watershed Management College of Natural Resources and Earth Sciences Shahrekord University Department of Soil Science College of Agriculture Ilam University Department of Wood and Forest Sciences Centre for Forest Research Laval University Irstea-National Research Institute of Science and Technology for Environment and Agriculture

This study aimed to investigate the interaction between regions with different climatic conditions(arid vs. semi-arid) and management(protected vs. unprotected) on the turnover and nestedness of vegetation in relation to physical, chemical and biological properties of soils in the Ilam Province of Iran. In each of the two regions, we sampled 8 sites(4 managed and 4 unmanaged sites) within each of which we established 4 circular plots(1000 m^2) that were used to investigate woody species, while two micro-plots(1 m×1 m) were established in each 1000-m^2 plot to analyze herbaceous species. In each sample unit, we also extracted three soil samples(0–20 cm depth) for measuring soil properties. The results indicated that the interaction between region and conservational management significantly affected the percent of canopy cover of Persian oak(Quercus brantii Linddl), soil respiration, substrate-induced respiration, as well as beta and gamma diversities and turnover of plant species. The percent of oak canopy cover was positively correlated with soil silt, electrical conductivity, available potassium, and alpha diversity, whereas it was negatively correlated with plant turnover. In addition, plant turnover was positively related to available phosphorus, while nestedness of species was positively related to organic carbon and total nitrogen. According to these results, we concluded that physical, chemical, and biological characteristics of limited ecological niche generally influenced plant diversity. Also, this study demonstrated the major contribution of the beta diversity on gamma diversity, especially in semi-arid region, because of the higher heterogeneity of vegetation in this area.

关键词： climatic conditions conservation management beta diversity oak forests physical-chemical property semi-arid region

Factors influencing the concentration of negative air ions during the year in forests and urban green spaces of the Dapeng Peninsula in Shenzhen, China

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Journal of Forestry Research 2020年第6期31卷 2537-2547页

作者： Yafei Wang Zhuobiao Ni Di Wu Chen Fan Jiaqi Lu Beicheng Xia School of Environmental Science and Engineering Sun Yat-sen University135 Xingang Xi RoadGuangzhou 510275People’s Republic of China Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology Sun Yat-sen University135 Xingang Xi RoadGuangzhou 510275People’s Republic of China Shenzhen Degrees of Freedom Environmental Protection Science and Technology Co. Ltd.ShenzhenPeople’s Republic of China

Negative air ions(NAIs)benefit the mental and physical health of humans,but rapid urbanization can decrease the abundance of *** the spatial and seasonal distribution of NAIs and determining the factors that infl uence the concentration during urbanization is thus *** the present study of a typical developing urban district in southern China,negative air ion concentrations(NAICs)in 60 forests sites and 30 urban green spaces were quantifi ed on seven consecutive days in each of the four *** seasonal variations in NAIC were revealed in forests and urban green spaces with trough values in *** progressively decreased from forests to urban green spaces and was infl uenced by local land morphology,vegetation characteristics,and climatic *** vast,heavily vegetated northeastern region was the richest area for NAIs,whereas the narrow central region(urbanized area)was the poorest,implying dramatic impacts of urbanization on the spatial distribution of *** relationship between air temperature and NAIC was better fi tted with a quadratic equation than a linear ***,the NAIC was more sensitive to local morphology in urban green spaces than in urban forests,indicating the vulnerability of NAIs in urbanized ***,the appropriate design of local urban morphology is critical.

关键词： forests Negative air ion concentration Urban green spaces Shenzhen

Topography and soil content contribute to plant community composition and structure in subtropical evergreen-deciduous broadleaved mixed forests

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Plant Diversity 2021年第4期43卷 264-274页

作者： Qichi Yang Hehe Zhang Lihui Wang Feng Ling Zhengxiang Wang Tingting Li Jinliang Huang Key Laboratory for Environment and Disaster Monitoring and Evaluation HubeiInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan430077China University of Chinese Academy of Sciences Beijing100049China School of Resource and Environment Hubei UniversityWuhan430062China

Topography and soil factors are known to play crucial roles in the species composition of plant communities in subtropical evergreen-deciduous broadleaved mixed *** this study,we used a systematic quantitative approach to classify plant community types in the subtropical forests of Hubei Province(central China),and then quantified the relative contribution of drivers responsible for variation in species composition and *** classified the subtropical forests in the study area into 12 community *** these,species diversity indices of three communities were significantly higher than those of *** each community type,species richness,abundance,basal area and importance values of evergreen and deciduous species were *** most community types,deciduous species richness was higher than that of evergreen *** regression analysis showed that the dominant factors that affect species composition in each community type are elevation,slope,aspect,soil nitrogen content,and soil phosphorus ***,structural equation modeling analysis showed that the majority of variance in species composition of plant communities can be explained by elevation,aspect,soil water content,litterfall,total nitrogen,and total ***,the major factors that affect evergreen and deciduous species distribution across the 12 community types in subtropical evergreendeciduous broadleaved mixed forests include elevation,slope and aspect,soil total nitrogen content,soil total phosphorus content,soil available nitrogen content and soil available phosphorus content.

关键词： Environmental factors Plant community Two-way indicator species analysis Detrended correspondence analysis Evergreen-deciduous broadleaved mixed forests Northwestern of Hubei