检索结果-南通市图书馆

Journal of Mountain Science 2008年第3期5卷 249-256页

作者： LU Xuyang CHENG Genwei XIAO Feipeng HUO Changfu Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The process-oriented model forest-dndc describing biogeochemical cycling of C and N and GHGs （greenhouse gases） fluxes （CO2, NO and N2O） in forest ecosystems was applied to simulate carbon sequestration and GHGs emissions in Abies fabric forest of the Gongga Mountains at southeastern edge of the Tibetan Plateau. The results indicated that the simulated gross primary production （GPP） of Abies fabric forest was strongly affected by temperature. The annual total GPP was 24,245.3 kg C ha^-1 yr^-1 for 2005 and 26,318.8 kg C ha^-1 yr^-1 for 2006, respectively. The annual total net primary production （NPP） was 5,935.5 and 4,882.2 kg C ha^-1 yr^-1 for 2005 and 2006, and the annual total net ecosystem production （NEP） was 4,815.4 and 3,512.8 kg C ha^-1 yr^-1 for 2005 and 2006, respectively. The simulated seasonal variation in CO2 emissions generally followed the seasonal variations in temperature and precipitation. The annual total CO2 emissions were 3,109.0 and 4,821.0 kg C ha^-1 yr^-1 for 2005 and 2006, the simulated annual total N2O emissions from forest soil were 1.47 and 1.36 kg N ha^-1 yr^-1 for 2005 and 2006, and the annual total NO emissions were 0.09 and o.12 kg N ha^-1 yr^-1 for 2005 and 2006, respectively.

关键词： Carbon sequestration forest-dndc GHGs Abiesfabric forest Gongga Mountains

Modelling Soil Greenhouse Gas Fluxes from a Broad-leaved Korean Pine forest in Changbai Mountain: forest-dndc Model Validation

在线全文

学校读者我要写书评

暂无评论

Journal of Resources and Ecology 2019年第2期10卷 127-136页

作者： YE Shu GUO Chuying HAN Jiayin ZHANG Leiming DAI Guanhua WEN Xuefa YU Guirui Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academyof Sciences Beijing 100101 China College of Resources and Environment University of Chinese Academy of Sciences Beijing 100190 China Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China

Fluctuations in soil greenhouse gas(GHG)are an important part of the terrestrial ecosystem carbon-nitrogen cycle,but uncertainties remain about the dynamic change and budget assessment of soil GHG *** high frequency and consecutive soil GHG fluxes measured with an automatic dynamic chamber system,we tested the applicability of the current forest-dndc model in simulating soil CH4,CO2 and N2O fluxes in a temperate broad-leaved Korean pine forest at Changbai *** results showed that the forest-dndc model reproduced general patterns of environmental variables,however,simulated seasonal variation in soil temperature,snow melt processes and soil moisture partly deviated from measured variables,especially during the non-growing *** modeled CH4 flux was close to the field measurement and co-varied mainly with soil temperature and *** modeled soil CO2 flux had the same seasonal trend to that of the observation along with variation in temperature,however,simulated CO2 flux in the growing season was *** modeled N2O flux attained a peak in summer due to the influence of temperature,which was apparently different from the observed peak of N2O flux in the freeze-thaw ***,both modeled CO2 flux and N2O flux were dampened by rainfall *** from consistent estimation of annual soil CH4 flux,the annual accumulation of CO2 and N2O was *** is still necessary to further optimize model parameters and processes using long-term high-frequency observation data,especially transference of heat and water in soil and GHG producing *** work will improve modeling,ecosystem carbon-nitrogen budget assessment and estimation of soil GHGs flux from the site to the region.

关键词： soil GHGs flux dynamic chamber method forest-dndc temperate forest

Modeling effects of temperature and precipitation on carbon characteristics and GHGs emissions in Abies fabric forest of subalpine

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2008年第3期20卷 339-346页

作者： LU Xuyang CHENG Genwei XIAO Feipeng FAN Jihui Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

Abies fabric forest in the eastern slope of Gongga mountain is one type of subalpine dark coniferous forests of southwestern China. It is located on the southeastern edge of the Qinghai-Tibet plateau and is sensitive to climatic changes. A process-oriented biogeochemical model, forest-dndc, was applied to simulate the effects of climatic factors, temperature and precipitation changes on carbon characteristics, and greenhouse gases （GHGs） emissions in A. fabric forest. Validation indicated that the forest-dndc could be used to predict carbon characteristics and GHGs emissions with reasonable accuracy. The model simulated carbon fluxes, soil carbon dynamics, soil CO2, N2O, and NO emissions with the changes of temperature and precipitation conditions. The results showed that with variation in the baseline temperature from -2℃ to ＋2℃, the gross primary production （GPP） and soil organic carbon （SOC） increased, and the net primary production （NPP） and net ecosystem production （NEP） decreased because of higher respiration rate. With increasing baseline precipitation the GPP and NPP increased slightly, and the NEP and SOC showed decreasing trend. Soil CO2 emissions increased with the increase of temperature, and CO2 emissions changed little with increased baseline precipitation. With increased temperature and decreased baseline temperature, the total annual soil N2O emissions increased. With the variation of baseline temperature from -2℃ to ＋2℃, the total annual soil NO emissions increased. The total annual N2O and NO emissions showed increasing trends with the increase of precipitation. The biogeochemical simulation of the typical forest indicated that temperature changes strongly affected carbon fluxes, soil carbon dynamics, and soil GHGs emissions. The precipitation was not a principal factor affecting carbon fluxes, soil carbon dynamics, and soil CO2 emissions, but changes in precipitation could exert strong effect on soil N2O and NO emissions.

关键词： carbon characteristics greenhouse gases (GHGs) forest-dndc Abies fabric forest

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

在线全文

学校读者我要写书评

暂无评论

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

Estimated Carbon Sequestration in a Temperate forest in Idaho of USA

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Natural Science 2017年第12期9卷 421-436页

作者： Zhaohua Dai Richard A. Birdsey Alexa J. Dugan USDA forest Service Newtown Square PA USA Commission for Environmental Cooperation Montreal Canada School of forest Resources and Environmental Science Michigan Technological University Houghton MI USA

Assessing carbon (C) sequestration in forest ecosystems is fundamental to supply information to monitoring, reporting and verification (MRV) for reducing deforestation and forest degradation (REDD). The spatially-explicit version of forest-dndc (Fdndc) was evaluated using plot-based observations from Nez Perce-Clearwater National forest (NPCNF) in Idaho of United States and used to assess C stocks in?about 16,000 km2. The model evaluation indicated that the Fdndc can be used to assess C stocks with disturbances in this temperate forest with a proper model performance efficiency and small error between observations and simulations. Aboveground biomass in this forest was 85.1 Mg C ha-1 in 2010. The mean aboveground biomass in the forest increased by about 0.6 Mg C ha-1 yr-1 in the last 20 years from 1990 to 2010 with spatial mean stand age about 98 years old in 2010. Spatial differences in distributions of biomass, net primary production and net ecosystem product are substantial. The spatial divergence in C sequestration is mainly associated with the spatial disparities in stand age due to disturbances, secondly with ecological drivers and species. Climate variability and change can substantially impact C stocks in the forest based on the climatic variability of spatial climate data for a 33-year period from 1981 to 2013. Temperature rise can produce more biomass in NPCNF, but biomass cannot increase with an increase in precipitation in this forest. The simulation with disturbances using observations and estimates for the time period from 1991 to 2011?showed the effects of disturbances on C stocks in forests. The impacts of fires and insects on C stocks in this forest are highly dependent on the severity, the higher, the more C loss to atmosphere due to?fires, and the more dead woods produced by fires and insects. The rates of biomass increase with an increase in stand age are different among the species. The changes in forest C stocks?in the forest are almost species

关键词： Disturbances Insects Fire Biomass forest-dndc Spatially-Explicit Modeling Approach REDD

气候变化对亚高山暗针叶林土壤温室气体排放的影响

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

生态环境学报 2009年第6期18卷 2194-2199页

作者：鲁旭阳霍常富范继辉程根伟中国科学院成都山地灾害与环境研究所四川成都610041 中国科学院成都山地灾害与环境研究所山地环境演变与调控重点实验室四川成都610041

利用生物地球化学模型forest-dndc模拟气候变化对贡嘎山亚高山暗针叶林土壤温室气体的释放的影响。以位于贡嘎山东坡海拔3000m的峨眉冷杉(Abies fabri)中龄林为研究对象,以1999-2006年8年的日气候数据进行平均得到的日平均最高温度、日... 详细信息

利用生物地球化学模型forest-dndc模拟气候变化对贡嘎山亚高山暗针叶林土壤温室气体的释放的影响。以位于贡嘎山东坡海拔3000m的峨眉冷杉(Abies fabri)中龄林为研究对象,以1999-2006年8年的日气候数据进行平均得到的日平均最高温度、日平均最低温度和日平均降水总量作为基线(Base)气候情景,另外设置了温度+2℃(T+)、温度-2℃(T-)、降水量+20%(P+)、降水量-20%(P-)、温度+2℃同时降水量+20%(T+P+)、温度-2℃同时降水量-20%(T-P-)、温度+2℃同时降水量-20%(T+P-)、温度-2℃同时降水量+20%(T-P+)8种气候变化情景。结果显示:贡嘎山峨眉冷杉林土壤CO2释放随着温度增加而增加,土壤N2O释放对降水量改变敏感,而土壤NO的释放对温度和降水的改变均比较敏感,二者表现为协同作用。温度+2℃同时降水量+20%(T+P+)情景下土壤CO2释放最高,高于基线情景的36.08%;温度-2℃同时降水量+20%(T-P+)情景下土壤CO2释放最低,低于基线情景的36.89%。土壤N2O释放随着降水量的增加而升高,随着降水量减少而降低;温度和降水量同时增加时土壤NO释放均高于单一增加温度或降水量情景,而温度和降水量同时降低时土壤NO释放均低于单一降低温度或降水量情景。

关键词：贡嘎山峨眉冷杉土壤呼吸 forest-dndc 气候变化

在线全文

学校读者我要写书评

暂无评论

贡嘎山冷杉林土壤CO_2释放的模拟研究

浙江林业科技 2009年第6期29卷 11-16页

作者：鲁旭阳范继辉霍常富程根伟中国科学院成都山地灾害与环境研究所四川成都610041 中国科学院贡嘎山高山生态系统观测试验站四川泸定626102

利用贡嘎山冷杉林1998年和1999年土壤CO2通量对生物地球化学循环模型forest-dndc进行校准和验证,通过调整温度和湿度对土壤根呼吸影响的计算公式和对模型参数的本土化,提高了模拟值与真实值之间的吻合程度,尤其是提高了冬季土壤CO2释放... 详细信息

利用贡嘎山冷杉林1998年和1999年土壤CO2通量对生物地球化学循环模型forest-dndc进行校准和验证,通过调整温度和湿度对土壤根呼吸影响的计算公式和对模型参数的本土化,提高了模拟值与真实值之间的吻合程度,尤其是提高了冬季土壤CO2释放模拟的准确性。校准后使土壤CO2日释放量模拟结果的平均误差(e)和相对平均误差(e′)分别下降了3.81 kg/hm2和13.49%,绝对平均误差(M)和相对绝对平均误差(M′)也同时降低;模型效率的Nash-Sutcliffe系数(Me)和冷模拟(利用默认参数)相比,也由0.651提高到0.683。模型验证结果表明,冷杉林土壤CO2释放通量模拟值大体上能够与实际观测值的季节变化和日变化保持一致,在释放的量上也与实际观测值相当。

关键词： CO2通量 forest-dndc 模型校准冷杉

喀斯特常绿与落叶阔叶混交林过去50年来的碳循环模拟

在线全文

学校读者我要写书评

暂无评论

地球与环境 2017年第1期45卷 96-105页

作者：李梦德刘立斌倪健中国科学院地球化学研究所环境地球化学国家重点实验室贵阳550081 中国科学院普定喀斯特生态系统观测研究站贵州普定562100 中国科学院大学北京100049

通过对forest-dndc模型的植被和土壤参数本地化校准,以气象插值数据为输入,模拟了贵州省普定县高原型喀斯特次生常绿与落叶阔叶混交林1965~2014年的土壤、植被和生态系统碳循环特征。结果表明,与冷模拟和实测值相比,参数本地化校准后的... 详细信息

通过对forest-dndc模型的植被和土壤参数本地化校准,以气象插值数据为输入,模拟了贵州省普定县高原型喀斯特次生常绿与落叶阔叶混交林1965~2014年的土壤、植被和生态系统碳循环特征。结果表明,与冷模拟和实测值相比,参数本地化校准后的模型能更准确地模拟春、秋、冬3个季节的土壤呼吸动态,而模拟的夏季土壤呼吸偏小;但统计检验指出,参数修订后的forest-dndc模型能够较好地模拟喀斯特森林土壤呼吸,降低了模拟误差,可用于喀斯特常绿与落叶阔叶混交林碳动态的模拟。进一步分析发现,1965~2014年喀斯特森林的碳通量除模拟早期的前3~4年急剧增加之外,随后总初级生产力(GPP)保持相对稳定,植物呼吸(Rplant)和生态系统呼吸(R_(ecosystem))随着森林发育而增加,土壤呼吸(R_(soil))减少,植被净初级生产力(NPP)呈迅速减小趋势;净生态系统碳交换量(NEE)亦较迅速下降,在2013年达到最低值-0.17 t C/ha,喀斯特森林由碳汇变为弱碳源。相关分析表明,年均温度和年降水对喀斯特常绿与落叶阔叶混交林的GPP和R_(soil)没有显著影响,但却显著影响NPP、R_(plant)、R_(ecosystem)和NEE。

关键词： forest-dndc 喀斯特常绿与落叶阔叶混交林碳循环

海南热带山地雨林林窗对土壤呼吸的影响及其模拟研究

在线全文

学校读者我要写书评

暂无评论

海南热带山地雨林林窗对土壤呼吸的影响及其模拟研究

作者：许全海南大学

学位级别：硕士

随着全球气候变暖,极端气候呈现出增多增强的变化趋势,台风俨然已成为我国沿海森林林窗的主要驱动力之一,森林林窗呈现增加的趋势。在此背景下,林窗对土壤呼吸的影响研究是森林土壤碳循环和全球气候变化研究中的前沿和热点。海南岛尖峰... 详细信息

随着全球气候变暖,极端气候呈现出增多增强的变化趋势,台风俨然已成为我国沿海森林林窗的主要驱动力之一,森林林窗呈现增加的趋势。在此背景下,林窗对土壤呼吸的影响研究是森林土壤碳循环和全球气候变化研究中的前沿和热点。海南岛尖峰岭是自然保存较为完好的热带原始林区,也是热带山地雨林的典型地区,极具研究价值。定量评估热带山地雨林林窗对土壤呼吸的影响,可以为热带森林生态系统土壤呼吸的准确估算和土壤有机碳管理提供科学依据。以海南岛尖峰岭热带山地雨林天然林林窗和60 hm2动态观测样地为研究对象,通过开展(台风干扰形成)林窗土壤呼吸的长期原位观测试验,设置去除\保留凋落物处理,分析凋落物对土壤呼吸的影响;通过分析林窗内外土壤的理化性质及气象要素的异质性特征,运用冗余分析方法研究土壤呼吸的排放与环境因子的关系,并利用forest-dndc模拟林窗内外土壤呼吸的排放规律,其主要研究结果如下:1、雨季初期尖峰岭热带山地雨林土壤蔗糖酶、脲酶、过氧化氢酶和酸性磷酸酶的活性分别在1 5.36～60.94 mg·g-1 d-1、0.30～0.68 mg·g-1 d-1、1.59～3.30 ml·g-1·20min-1 和0.61～1.13 mg·g-1·h-1之间,土壤酶活性与环境因子的冗余分析的结果表明:土壤有机碳和全氮是雨季影响土壤酶活性的重要影响因子,它们分别能解释土壤酶活性变异的为 36.9%和 26.6%。2、林窗内外空气温度、空气相对湿度和地下5 cm 土壤温度、土壤含水量具有明显的日变化和月变化特征,日变化和月变化均呈现出单峰型的变化,在日变化尺度上,配对T检验的结果表明,林窗的空气温度、空气相对湿度和土壤温度与林内均存在极显著差异性(P0.05)。林窗的土壤有机碳、全氮、全磷、铵态氮、硝态氮、蔗糖酶、脲酶和过氧化氢酶的含量分别为35.84 g·kg-1、2.33 g·kg-1、0.14 g·kg-1、8.80 mg kg-1、11.52 mg kg-1、33.58 mg g-1 d-1、0.33 mg·g-1 d-1和3.38 ml g-1·20 min-1;林内的土壤有机碳、全氮、全磷、铵态氮、硝态氮、蔗糖酶、脲酶和过氧化氢酶的含量分别为 36.04 g·kg-1、2.37 g·kg-1、0.16 g·kg-1、10.79 mg·kg-1、10.24 mg·kg-1、43.98 mg·g-1·d-1、0.37 mg·g-1·d-1和3.57 ml·g-1·20 min-1。配对T检验的结果表明,林窗土壤全磷、蔗糖酶、脲酶和过氧化氢酶与林内存在显著差异性(P0.05)。3、2014～2018年林窗年平均土壤呼吸速率分别为2.68、2.17、3.10、2.69和3.29μmol·m-2·s-1;林内年平均土壤呼吸速率分别为2.54、2.11、2.81、2.49和2.38μmol·m-2·s-1。方差分析的结果表明,2014～2017年林窗内外的土壤呼吸差异性不显著(P>0.05),2018年的林窗和林内的土壤呼吸存在显著差异性(P<0.05),其中,雨季的土壤呼吸显著大于旱季的土壤呼吸(P<0.05)。全年林窗和林内地上凋落物对土壤呼吸的贡献率分别为31.96%和22.38%。在月和年际尺度上,林窗内外的土壤呼吸的排放速率呈现多峰型曲线变化规律,排放趋势大致相同,整体呈现出雨季大于旱季的变化规律。4、土壤呼吸与环境因子的冗余分析的结果表明,地下5 cm 土壤温度和有机碳是影响土壤呼吸最主要的环境因子,分别解释了土壤呼吸变异性的1 5.7%和6.7%(P<0.05);地下5 cm 土壤温度和土壤脲酶是影响林窗土壤呼吸的最主要环境因子,分别解释了土壤呼吸变异性的26.2%和3.5%(P<0.05);地下5 cm 土壤温度和有机碳是影响林内土壤呼吸的最主要因素,分别解释了土壤呼吸变异性的10.7%和15.8%(P

关键词：热带山地雨林土壤呼吸林窗 forest-dndc