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Dynamics of soil inorganic nitrogen and their responses to nitrogen additions in three subtropical forests, south China

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Journal of Environmental Sciences 2006年第4期18卷 752-759页

作者： FANG Yun-ting ZHU Wei-xing MO Jiang-ming ZHOU Guo-yi GUNDERSEN Per Dinghushan forest Ecosystem Research Station South China Botanical Garden Chinese Academy of Sciences Zhaoqing 526070 China Biological Sciences Binghamton University-SUNY Binghamton NY 13902-6000 USA forest and landscape denmark Hoersholm Kongevej 11 2970 Denmark The Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Three forests with different historical land-use, forest age, and species assemblages in subtropical China were selected to evaluate current soil N status and investigate the responses of soil inorganic N dynamics to monthly ammonium nitrate additions. Results showed that the mature monsoon evergreen broadleaved forest that has been protected for more than 400 years exhibited an advanced soil N status than the pine （Pinus massoniana） and pine-broadleaf mixed forests, both originated from the 1930＇s clear-cut and pine plantation. Mature forests had greater extractable inorganic N pool, lower N retention capacity, higher inorganic N leaching, and higher soil C/N ratios. Mineral soil extractable NH4^＋-N and NO3-N concentrations were significantly increased by experimental N additions on several sampling dates, but repeated ANOVA showed that the effect was not significant over the whole year except NH4^＋-N in the mature forest. In contrast, inorganic N （both NH4^＋-N and NO3^--N） in soil 20-cm below the surface was significantly elevated by the N additions. From 42% to 74% of N added was retained by the upper 20 cm soils in the pine and mixed forests, while 0%-70% was retained in the mature forest. Our results suggest that land-use history, forest age and species composition were likely to be some of the important factors that determine differing forest N retention responses to elevated N deposition in the study region.

关键词： N deposition N saturation extractable inorganic N soil solution inorganic N subtropical China

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Response of Nitrogen Leaching to Nitrogen Deposition in Disturbed and Mature forests of Southern China

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Pedosphere 2009年第1期19卷 111-120页

作者： FANG Yun-Ting M. YOH MO Jiang-Ming P. GUNDERSEN ZHOU Guo-Yi Dinghushan forest Ecosystem Research Station South China Botanical Garden the Chinese Academy of Sciences Zhaoqing Guangdong 520670 （China） Tokyo University of Agriculture and Technology Tokyo 183-8509 （Japan） forest ＆ landscape denmark Faculty of Life Sciences University of Copenhagen Hoersholm Kongevej 112970 （Denmark）

Current nitrogen (N) leaching losses and their responses to monthly N additions were investigated under a disturbed pine (Pinus massoniana) forest and a mature monsoon broadleaf forest in southern China. N leaching losses from both disturbed and mature forests were quite high (14.6 and 29.2 kg N ha-1 year-1, respectively), accounting for 57% and 80% of their corresponding atmospheric N inputs. N leaching losses were substantially increased following the first 1.5 years of N applications in both forests. The average increases induced by the addition of 50 and 100 kg N ha-1 year-1 were 36.5 and 24.9 kg N ha-1 year-1, respectively, in the mature forest, accounting for 73.0% and 24.9% of the annual amount of N added, and 14.2 and 16.8 kg N ha-1 year-1 in the disturbed forest, accounting for 28.4% and 16.8% of the added N. Great N leaching and a fast N leaching response to N additions in the mature forest might result from long-term N accumulation and high ambient N deposition load (greater than 30 kg N ha-1 year-1 over the past 15 years), whereas in the disturbed forest, it might result from the human disturbance and high ambient N deposition load. These results suggest that both disturbed and mature forests in the study region may be sensitive to increasing N deposition.

关键词：大气氮沉积氮增加氮流失氮饱和亚热带森林

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Has global deforestation accelerated due to the COVID-19 pandemic?

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Journal of forestry Research 2023年第4期34卷 1153-1165页

作者： Jonnathan Céspedes Janelle M.Sylvester Lisset Pérez-Marulanda Paula Paz-Garcia Louis Reymondin Mehran Khodadadi Jhon J.Tello Augusto Castro-Nunez The Alliance of Bioversity International and International Center for Tropical Agriculture(CIAT) Km 17 Recta Cali-PalmiraCaliColombia Department of Geosciences and Natural Resource Management University of CopenhagenCopenhagenDenmark Leibniz Centre for Agricultural landscape Research(ZALF) MünchebergGermany

As the COVID-19 pandemic unfolded,questions arose as to whether the pandemic would amplify or pacify tropical *** reports warned of increased deforestation rates;however,these studies were limited to a few months in 2020 or to selected *** better understand how the pandemic infl uenced tropical deforestation globally,this study used historical deforestation data(2004–2019)from the Terra-i pantropical land cover change monitoring system to project expected deforestation trends for 2020,which were used to determine whether observed deforestation deviated from expected trajectories after the fi rst COVID-19 cases were *** series analyses were conducted at the regional level for the Americas,Africa and Asia and at the country level for Brazil,Colombia,Peru,the Democratic Republic of Congo and *** results suggest that the pandemic did not alter the course of deforestation trends in some countries(e.g.,Brazil,Indonesia),while it did in others(e.g.,Peru).We posit the importance of monitoring the long-term eff ects of the pandemic on deforestation trends as countries prioritize economic recovery in the aftermath of the pandemic.

关键词： Deforestation COVID-19 Time series Terra-i Drivers of deforestation monitoring

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Sap flow for beech(Fagus sylvatica L.)in a natural and a managed forest—effect of spatial heterogeneity

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Journal of Plant Ecology 2011年第1期4卷 23-35页

作者： Lise Dalsgaard Teis Nørgaard Mikkelsen Annemarie Bastrup-Birk forest and landscape Faculty of Life SciencesUniversity of CopenhagenRolighedsvej 231958 Frederiksberg CDenmark RisøNational Laboratory for Sustainable Energy Technical University of DenmarkFrederiksborgvej 399P.O.Box 494000 RoskildeDenmark

Aims Beech(Fagus sylvatica L.)is an important species in natural and managed forests in *** drought-sensitive species dominates even-aged stands as well more natural stands composed of a mixture of tree species,age and size *** study evaluates the extent that heterogeneity in spacing and tree diameter affect the seasonal availability and use of *** Two stands were evaluated:(i)a heterogeneous forest remnant(NAT)with trees up to;300 years old,a mean top height of 28.4 m and a total of 733 stems ha1with stem diameters averaging 18 cm and(ii)an even-aged 80-year old stand(MAN),with a height of 25 m,and a total of 283 stems ha1 with diameters averaging 38 *** sap flow,Js(g m2 s1),was continuously measured in 12(MAN)and 13(NAT)trees using 20-mm long heat dissipation *** tree measures of sap flow were correlated using non-linear statistical methods with air vapour pressure deficit(D,hPa)and global radiation(Rg,J m2 day1),along with constraints imposed by reductions in soil water content(SWC).SWC was measured as volumetric%using time domain *** Findings The daily integrated Js(Js-sum)for trees growing in the evenly spaced MAN stand and trees in canopy and closed forest positions in NAT stand decreased as the availability of soil moisture was *** the heterogeneous NAT stand,SWC in a recently formed canopy gap remained high throughout the vegetation *** on regression models,the predicted relative decrease in Js-sum for dry relative to moist soil water conditions in the closed forest(at mean daily D=10 hPa)was 7–11%for trees near the gap and 39–42%for trees in the closed *** MAN,the reduction in Js-sum was 29%in dry relative to moist ***-sum in the outer 20 mm of the xylem in NAT was lower than that in MAN and the rate of decline in Js with xylem depth was less in NAT than in *** MAN,Js-sum in deep and outer xylem was negatively affected at low soil moisture availability

关键词： canopy gap canopy structure tree size tree water use

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Response of soil fauna to simulated nitrogen deposition: A nursery experiment in subtropical China

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Journal of Environmental Sciences 2007年第5期19卷 603-609页

作者： XU Guo-liang MO Jiang-ming FU Sheng-lei PER Gundersen ZHOU Guo-yi XUE Jing-Hua Institute of Ecology South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Danish Center for forest Landscape and Planning KVL Hoersholm Kongevej 11 DK-2970 Hoersholm Denmark

We studied the responses of soil fauna to a simulated nitrogen deposition in nursery experimental plots in Subtropical China. Dissolved NH4NO3 was applied to the soil by spraying twice per month for 16 months, starting January 2003 with treatments of 0, 5, 10, 15 and 30 gN/（m^2·a）. Soil fauna was sampled after 6, 9, 13 and 16 months of treatment in three soil depths （0-5 cm, 5-10 cm, 10-15 cm）. Soil available N increased in correspondence with the increasing N treatment, whereas soil pH decreased. Bacterial and fungal densities were elevated by the N treatment. Soil fauna increased in the lower nitrogen treatments but decreased in the higher N treatments, which might indicate that there was a threshold around 10 gN/（m^2·a） for the stimulating effects of N addition. The N effects were dependent on the soil depth and sampling time. The data also suggested that the effects of the different N treatments were related to the level of N saturation, especially the concentration of NO3^- in the soil.

关键词： soil fauna N deposition response Subtropical China

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A Case Study Report for Urban forestry Policy Project Co-funded by EC:Analysis of Urban forestry Policy in Hangzhou,China

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Chinese forestry Science and Technology 2008年第1期7卷 13-19页

作者： Stephan Pauleit Danish Centre for forest Landscape and Planning University of Copenhagen DK 1958 Frederiksberg Denmark

Hangzhou is a typical city on the establishment of urban forest in China, so it was identified as a case study site in Urban forestry Policy Project Co-funded by EC. The name of the project is "Developing Policy Formulation and Implementation Tools for Providing Support for Ecological forest Management in China’s Urban and Peri-Urban Areas". Experts from the project team have conducted a field survey on urban forestry policy in Hangzhou for one week. Through the field survey and the workshop, the experts understand the current development of urban forestry, the management institutions, the policy framework, the policy- making and the implementation procedure in Hangzhou. The impacts of urban policy and experiences of urban forest planning and management were analyzed. Finally, the main existing problems of urban forestry development were concluded and related policy recommendations in Hangzhou were provided.

关键词： Hangzhou urban forestry administrative agency policy formulation implementation impacts measures

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Urban forestry as a Vehicle for Healthy and Sustainable Development

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Chinese forestry Science and Technology 2005年第1期4卷 1-14页

作者： NILSSON Kjell Danish Centre for forest Landscape and Planning Rolighedsvej 23 DK-1958 Frederiksberg C Denmark

Urban forestry has been defined as the art, science and technology of managing trees and forestresources in and around urban community ecosystems for the physiological, sociological, economic andaesthetic benefits trees provide. The importance of urban forestry has received limited attention in manypoor countries as it is often percieved as being associated with beautification projects, which are considereda luxury benefiting only the wealthier part of the population. However, urban forestry may have a number ofenvironmental, economic and socio-cultural values, which will also benefit poorer segments of city *** in poorer countries, planning for urban trees and forests is a good investment, as these areas will bedemanded when income levels increase. Once everything is allocated to other construction or infrastructure,it may be very difficult to create new green areas unless these are planned *** Danish Centre for forest, landscape and Planning has been leading actor in the development of Urbanforestry during the last decade. EUFORIC (European Urban forestry Research and Information Centre),COST Action E12 Urban forests and Trees and E39 forests, Trees and Human Health and Wellbeing areall examples of activities initiated and coordinated by the Danish centre. It has also developed urban forestryand urban greening as a concept for environment and development aid projects in Eastern Europe anddeveloping countries in Southeast Asia and Southern Africa. Over the coming years, the main challange willbe to ensure that the expansion of the green infrastructure in the worlds urban areas is implemented withinthe framework of sustainability and human health and well-being, without the use of a technology inimical toman and nature and with as few chemical aids as possible.

关键词：城市森林可持续发展城市生态环境人类健康城市绿化约翰内斯堡马来西亚

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Higher Education on Urban forestry in Europe: An Overview

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Chinese forestry Science and Technology 2003年第3期2卷 16-27页

作者： ANDERSEN FRODE KONIJNENDIJK CECIL C RANDRUP THOMAS B Skov SkovSkov & LandskabDanish Forest and Landscape Research Institute Hφrsholm Kongevej 11DK-2970 HφrsholmDenmark& LandskabDanish Forest and Landscape Research Institute Hφrsholm Kongevej 11DK-2970 HφrsholmDenmark Corresponding author& LandskabDanish Forest and Landscape Research Institute Hφrsholm Kongevej 11.DK-2970 Hφrsholm. Denmark

In order to meet the demands of modern, information-based society, higher education in natural resource management needs to be transformed. Enhanced mobility of students and staff, multi- and transdisciplinary approaches, as well as innovative educational approaches are called for. Moreover, the urban component needs to be better incorporated, as exemplified by the emerging field of urban forestry. This paper relates to the developments in higher education within the context of education on urban forest...

关键词： higher education urban forestry Europe

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Effect of Simulated N Deposition on Soil Exchangeable Cations in Three forest Types of Subtropical China

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Pedosphere 2009年第2期19卷 189-198页

作者： LU Xian-Kai MO Jiang-Ming P.GUNDERSERN ZHU Wei-Xing ZHOU Guo-Yi LI De-Jun ZHANGXu Dinghushan forest Ecosystem Research Station South China Botanical Garden Chinese Academy of Sciences Zhaoqing 526070 China Danish Centre for forest Landscape and Planning University of Copenhagen Hoersholm Kongevej 11 DK-2970 Hoersholm Denmark Department of Biological Sciences State University of New York Binghamton NY 13902-6000 （USA） Nanjing Agricultural University Nanjing 210095 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The effects of simulated nitrogen(N)deposition on soil exchangeable cations were studied in three forest types of subtropical *** N treatments with three replications were designed for the monsoon evergreen broadleaf forest (mature forest):control(0 kg N ha-1 year-1),low N(50 kg N ha-1 year-1),medium N(100 kg N ha-1 year-1)and high N(150 kg N ha-1 year-1),and only three treatments(i.e.,control,low N,medium N)were established for the pine and mixed *** had been applied continuously for 26 months before the *** mature forest responded more rapidly and intensively to N additions than the pine and mixed forests,and exhibited some significant negative symptoms,e.g.,soil acidification,Al mobilization and leaching of base cations from *** pine and mixed forests responded slowly to N additions and exhibited no significant response of soil *** of soil exchangeable cations to N deposition varied in the forests of subtropical China,depending on soil N status and land-use history.

关键词：交换性阳离子亚热带森林土壤酸化森林类型氮沉降模拟可交换季风常绿阔叶林

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Effects of micro-environmental conditions and forest disturbance on the establishment of two Andean palms in Ecuador

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Open Journal of Ecology 2012年第4期2卷 233-243页

作者： Diana Rodríguez-Paredes Rommel Montúfar-Galárraga Henrik Meilby Ecology and Genetics Pontificia Universidad Católica del Ecuador Quito Ecuador forest & landscape University of Copenhagen Copenhagen Denmark

The wax palm (Ceroxylon echinulatum) and palm heart (Prestoea acuminata) are key elements in Andean natural forests. This ecosystem is threatened by deforestation and habitat degradation, thus, it is vital to explore the impact of anthropogenic activities on the ecological structure and preferences of these species in order to develop proper conservation strategies. Fifty-seven 400 m2 plots were established in two forest areas, a disturbed forest (n = 30 plots) and an undisturbed forest (n = 27 plots) in the Ecuadorean Andes. Nine micro-environmental variables and the number of individuals of C. echinulatum and P. acuminata in five size classes were recorded in each plot. Logistic regression models helped identify environmental variables that influence the establishment of the species. Results showed that different micro-environmental variables determined the presence of different size classes. Both species were benefitted by the environmental conditions of the disturbed forest. Light availability was important for the establishment of both species, especially for the canopy species (C. echinulatum). This palm was negatively affected by the variable “fallen wood”, while P. acuminata was negatively affected mainly by the steepness of the terrain. The environmental variables for the successful establishment of the studied species that were identified by this study provide clues for the sustainable management of C. echinulatum and P. acuminata in Andean forests.

关键词： Andean forest Ceroxylon forest Disturbance Micro-Environmental Variables Palm Establishment Prestoea Sustainable Management

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