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Heavy metal accumulation by panicled goldenrain tree(Koelreuteria paniculata) and common elaeocarpus(Elaeocarpus decipens) in abandoned mine soils in southern China

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Journal of Environmental Sciences 2009年第3期21卷 340-345页

作者： TIAN Dalun ZHU Fan yan wende Fang Xi XIANG Wenhua DENG Xiangwen WANG Guangjun PENG Changhui Section of Ecology Research Central-South University of Forestry& Technology Hunan 410004 China Institute of Environment Sciences Department of Biology Sciences University of Quebec at Montreal Case postale 8888 succ Centre-Ville Montreal (QC) H3C 3P8 Canada

Phytoremediation can be used as a sustainable technology for mine spoil remediation to remove heavy metals. This study investigated the concentration of 7 heavy metal contamination in soil and plant samples at an abandoned mine site. We found that, after vegetation remediation at the abandoned mine site, the reduction rates for 7 heavy metals were in the range of 4.2%-86%, where reduction rates over 50% were achieved for four heavy metals （Zn, Mn, Cd, Ni）. Transfer coefficients of the panicled goldenrain tree （Koelreuteria paniculata Laxm） and the common elaeocarpus （Elaeocarpus decipens） for Zn, Mn, Ni, and Co were more than 1. Enrichment coefficients of both trees for Mn were higher than 1. Our results suggest that the panicled goldenrain tree and the common elaeocarpus tree may act as accumulators in remediation. Moreover, the woody vegetation remediation in abandoned mining areas play an important role in improving scenery besides removing heavy metal from contaminated soil.

关键词： panicled goldenrain tree (Koelreuteria paniculata) common elaeocarpus (Elaeocarpus decipens) heavy metal elements accumulation abandoned mine sites

Impacts of changed litter inputs on soil CO2 efflux in three forest types in central south China

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Science Bulletin 2013年第7期58卷 750-757页

作者： yan wende CHEN XiaoYong TIAN DaLun PENG YuanYing WANG GuangJun ZHENG Wei National Engineering Laboratory for Applied Forest Ecological Technology in Southern China College of Life Science and Technology Central South University of Forestry and Technology College of Arts and Sciences Governors State UniversityUniversity Park Natural Sciences Division College of DuPage

Climate change is expected to cause the alteration of litter production in forests,which may result in substantial changes in soil CO2 efflux (FCO2) process as litter represents a major pathway of carbon from vegetation to the *** this study,we conducted an aboveground litter manipulation experiment to examine the influence of litter addition and exclusion on soil FCO2 in Camphor tree,Masson pine,and mixed Camphor tree and Masson pine forests in central south *** input manipulation included three treatments:non-litter input (litter exclusion),double litter input (litter addition),and natural litter input (control).On average,litter exclusion significantly reduced soil FCO2 rate by approximately 39%,24% and 22% in Camphor tree forests,the Mixed forests,and Masson pine forests,*** a yearly basis,double litter addition significantly increased soil CO2 by 12% in the Mixed forests (P=0.02) but not in both Camphor tree and Masson pine forests (P>0.05),when compared with their corresponding control ***,litter addition increased soil FCO2 rates in the months of June-August in Camphor tree and Masson pine forests,coinciding with high soil temperature of summer *** exclusion reduced soil FCO2 more than litter addition increased it in the study *** of soil respiration to litter input treatments varied with forest *** input treatments did not alter the seasonal patterns of soil temperature and soil water *** results indicated that changes in aboveground litter as a result of global climate change and/or forest management have a great potential to alter soil respiration and soil carbon balance in forest ecosystems.

关键词： soil respiration litter exclusion litter addition subtropical forests soil environmental factors

Phenomenological models of diffusivities based on local composition

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化工进展 2011年第S2期30卷 30-35页

作者： yan Jianmin,XIAO wende (School of Chemistry and Chemical Engineering,Shanghai JiaoTong University,Shanghai 200240)

In phenomenological models,diffusivity is at least a function of composition and the diffusivities at infinite *** additional parameter(?),which can be determined by diffusivity in midpoint,are specially brought forward as token of fractional friction related with the interactions of same molecules in this paper,to extrapolate a new correlative equation for the mutual Maxwell-Stefan ***,the correlative equation can be extended to calculate diffusivities in multicomponent mixtures based on binary data *** theoretical calculations are evaluated with published experimental *** M-S diffusivities in a three-component liquid system are regarded as binary coefficients,the predictive results also agree with the experimental *** indicate that the model with additional coefficients is superior to currently used Darken methods,especially for systems of polar organic-water and those containing associative component.

关键词： diffusivity diffusion phenomenological models Maxwell-Stefan’s law

杉木叶片性状不支持广为接受的通量性状网络假说

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Journal of Plant Ecology 2023年第2期16卷 151-161页

作者： Xi Peng Meifang Zhao Shuguang Liu wende yan College of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China Huitong National Field Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province Huitong 410015China National Engineering Laboratory for Applied Technology of Forestry and Ecology in Southern China Changsha 410004China

“高叶脉密度-更快生长和更高的生产力”模型和假说认为高叶脉密度能促进更高的碳和水的耦合效率,暗示了个体的快速生长和高林分生产力,这些假说被研究者广泛关注和认同。然而,这些模型和假说并没有包括足够的裸子植物样本,特别是在亚... 详细信息

“高叶脉密度-更快生长和更高的生产力”模型和假说认为高叶脉密度能促进更高的碳和水的耦合效率,暗示了个体的快速生长和高林分生产力,这些假说被研究者广泛关注和认同。然而,这些模型和假说并没有包括足够的裸子植物样本,特别是在亚热带栽培的针叶树种。我们在此研究了叶脉密度和叶功能性状的值和比例关系,这些样本来自于以快速生长著称的杉木(Cunninghamia lanceolata)的主要分布区。我们还检索了一个经验数据集,该数据集包括杉木的光合作用、生物化学、解剖学和水力特性。杉木叶脉密度(范围为0.34–1.09 mm/mm)远低于全球报道的范围(1–25 mm/mm),而杉木以快速生长和高产在中国长期闻名。我们进一步证实,较高的脉络密度与较小的叶片负相关(r=-0.71,P<0.001),这与被子植物中发现的情况一致。然而,我们发现,与全球物种(正相关)相比,杉木的叶脉密度-叶厚相关性和叶片寿命可塑性呈现相反的趋势,这种关系可能暗示功能效率和生产力间的权衡。我们的结果将为普适的生长规律提供有效的补充评估,包括评价区域植物性状特征、植物物种的配置和性状效率对水力潜能的影响。

关键词：叶脉密度叶片大小叶片厚度性状可塑性种类变异

Soil respiration dynamics in Cinnamomum camphora forest and a nearby Liquidambar formosana forest in Subtropical China

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Chinese Science Bulletin 2010年第16期55卷 736-743页

作者： TIAN DaLun WANG GuangJun yan wende XIANG WenHua PENG ChangHui Faculty of Life Science and Technology Central South University of Forestry & Technology Changsha 410004 China Institut des sciences de l'environnement Departement des sciences biologiques Universite du Quebec a Montreal Montreal QC H3C 3P8 Canada

Climate change can significantly affect carbon cycling of forest *** diurnal and seasonal dynamics of soil respiration (Rs) in Cinnamomum camphora and Liquidambar formosana forests were investigated by using infrared gas exchange analyzer of Li-Cor 6400-09 each month in *** temperature and moisture were also *** variations in Rs varied with daily soil temperature in the two *** the growing season,soil respiration peaked on July 28 due to higher soil temperature and moisture *** Rs variations were predominantly influenced by soil *** soil respirations in *** and *** forests were strongly related to soil temperature (x) at 5-cm depth (Rs=0.1598e 0.1377x (R 2=0.9289,P=0.001) and Rs=0.2177e 0.0962x (R 2=0.927,P=0.000)),while annual mean Rs rate was 2.614 and 1.397 μmol m-2 s-1 and Q 10 values were 3.96 and 2.62 for the two forests,***,Rs was not influenced by seasonal changes in soil moisture (w) in the two forests in *** developed two equations (Rs=-0.020w 2 +0.497w+0.562 (R 2=0.109,P>0.05),Rs=-0.001w 2 +0.072w +0.731(R 2=0.053,P>0.05)) to describe the relationship between Rs and soil moisture.A positive relationship between Rs and soil moisture were observed when soil moisture was below 12.43% and 18.00%,but when soil moisture exceeded threshold values of 12.43% and 18.00%,soil moisture became the restraint factor for ***-term observations of soil respiration and moisture are required to understand the temporal dynamics of soil respiration.

关键词：亚热带森林土壤呼吸中国树林

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Mathematical model study on the damage of the liquid phase to productivity in the gas reservoir with a bottom water zone

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Petroleum 2018年第2期4卷 209-214页

作者： Xiaoliang Huang Xiao Guo Xinqian Lu Xiang Zhou Zhilin Qi wende yan Jiqiang Li College of Petroleum Engineering Southwest Petroleum UniversityChengdu610500China School of Petroleum Engineering Chongqing University of Science&TechnologyChongqing401331China Petroleum Systems Engineering Faculty of Engineering and Applied Science University of ReginaReginaS4S 0A2Canada

The production process in the gas reservoir with an aquifer is *** gas production,aquifer water could possibly flow into the production well and accumulate within the well bore,which leads to a lower production rate and may even block the ***,few studies in the literature investigate the damage caused by the liquid phase in this kind of reservoir or predict gas productivity using the relationship between reservoir pressure and water gas ratio(WGR).For this reason,it is important to know the effects of the formation of liquid phase behavior on production when an aquifer is present under a gas *** the results of published literature reviews,we found that studies focused on the production of a gas reservoir with bottom ***,for gas well damage from the liquid phase behavior,we found that there was no statistical data or mathematical model of the relationship between reservoir pressure and the gas oil ratio(GOR),which affects *** this research,based on the theory of fluid flow in porous media,a new mathematical model of water and gas production and a new equation on gas well productivity is *** verify the model and equation,gas production data collected from the field are *** analyzing the typical gas reservoir with bottom water and the collected data,influences from the liquid phase behavior are *** this way,mathematical relationships between reservoir pressure and the WGR and between the GOR and production decline were *** new gas productivity model is derived from the gas and water pseudo pressure functions,which can be applied to analyze well damage caused by the liquid *** order to verify the mathematical model,production data were collected from a typical gas reservoir with an aquifer located in the Changxing gas *** results indicate that a semi-logarithmic linear relationship is obtained between the WGR and productivity *** the WGR increases from 0.5 to

关键词： Mathematical model Liquid phase Well productivity Gas reservoir with an aquifer

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土壤微食物网与森林土壤固碳的进展与思考

中南林业科技大学学报 2023年第11期43卷 1-12页

作者：闫文德中南林业科技大学湖南长沙410004

森林土壤碳库在全球气候调控和碳平衡维持方面具有至关重要的作用。作为碎屑食物网的起点,土壤微食物网是森林生态系统地上-地下碳转化的关键驱动者,决定着森林土壤有机碳的分解、转化和储存等过程,影响着森林生态系统的固碳潜力。首先... 详细信息

森林土壤碳库在全球气候调控和碳平衡维持方面具有至关重要的作用。作为碎屑食物网的起点,土壤微食物网是森林生态系统地上-地下碳转化的关键驱动者,决定着森林土壤有机碳的分解、转化和储存等过程,影响着森林生态系统的固碳潜力。首先,从土壤微食物网的结构组成的视角出发,分析了微食物网不同组分对森林土壤碳库的影响途径。其次,以土壤微食物网各组分之间的相互作用为支点,进一步从能量流动角度分析其对土壤有机碳的传递过程,从营养级联层面探讨其对土壤碳储存的调控作用,从微食物网复杂性和稳定性的变化探索其对森林土壤固碳能力的反馈机制。最后,针对目前土壤微食物网研究存在的不足和局限性,在厘清多组分的微食物网结构特征,解构多元化的微食物网关系网络,以及探索切实有效的微食物网调控策略等方面提出相关建议。在“双碳”战略目标建设背景下,本研究为提升森林生态系统的固碳潜力提供新的研究思路和理论支撑。

关键词：土壤微食物网能量流动营养级联复杂性和稳定性森林生态系统土壤固碳

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Impacts of changed litter inputs on soil CO_2 efflux in three forest types in central south China

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Science China(Technological Sciences) 2013年第3期56卷 750-757页

Climate change is expected to cause the alteration of litter production in forests, which may result in substantial changes in soil CO2 effiux （FCO2） process as litter represents a major pathway of carbon from vegetation to the soils. In this study, we conducted an aboveground litter manipulation experiment to examine the influence of litter addition and exclusion on soil FCO2 in Camphor tree, Masson pine, and mixed Camphor tree and Masson pine forests in central south China. Litter input manipulation included three treatments： nonqitter input （litter exclusion）, double litter input （litter addition）, and natural litter input （control）. On average, litter exclusion significantly reduced soil FCO2 rate by approximately 39%, 24% and 22% in Camphor tree forests, the Mixed forests, and Masson pine forests, respectively. On a yearly basis, double litter addition significantly increased soil CO2 by 12% in the Mixed forests （P=0.02） but not in both Camphor tree and Masson pine forests （P〉0.05）, when compared with their corre- sponding control treatments. However, litter addition increased soil FCO2 rates in the months of June-August in Camphor tree and Masson pine forests, coinciding with high soil temperature of summer conditions. Litter exclusion reduced soil FCO2 more than litter addition increased it in the study sites. Responses of soil respiration to litter input treatments varied with forest types. Litter input treatments did not alter the seasonal patterns of soil temperature and soil water content. Our results indicated that changes in aboveground litter as a result of global climate change and/or forest management have a great potential to alter soil respiration and soil carbon balance in forest ecosystems.

关键词： soil respiration litter exclusion litter addition subtropical forests soil environmental factors

Short-term Effects of Nitrogen Deposition on Soil Respiration of Cinnamomum camphora Plantation

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Chinese Forestry Science and Technology 2012年第3期11卷 37-38页

作者： Zhang Xuyuan yan wende Ma Xiuhong Zheng Wei Wang Guangjun Liang Xiaocui School of Life Science & Technology Central South University of Forestry & Technology National Engineering Laboratory for Applied Technology of Forestry & Ecology in South China Tianzhu Nursery Garden

The nitrogen deposition experiments on Cinnamomum camphora plantation of Hunan provincial botanical garden were simulated from June the 7th to October the 7th,2010,the nitrogen deposition levels was respectively as control(CK, 0 g·m-2 a-1),low nitrogen(LN,5 g·m-2 a-1),medium nitrogen(MN,15 g·m-2 a-1) and high nitrogen(HN, 30 g·m -2 a-1).The soil respiration speed and soil surface temperature and the surface water content of the soil were determined by LI-8100 measuring *** results show that the average values of soil respiration speed were CK (4.09±0.66μmol·m-2 s-1),LN(2.39±029μmol·m-2 s-1), MN(2.18±0.19μmol·m-2s-1),HN (2.28±0.25μmol·m-2 s-1),and the treatment of the CK was obviously higher than the other three treatments（P10 （temperature sensitivity coefficients） for soil respiration of CK,LN,MN and HN treatments were 1.84,1.71,1.83 and *** was positive correlation between the respiration speed and the surface（≤10 cm） temperature of tested *** was negative correlation between the respiration speed and the surface（≤5 cm） water content of tested soil（P>0.05）.Volumetric water content of 5-cm soil was between 0.266 6-0.294 4(m3·m-3), and the monthly content did not vary too much during the research period（1.8%-9.4%）.The findings suggest that the initial stage of nitrogen deposition obviously influenced the soil respiration of *** plantation.

关键词： soil respiration nitrogen deposition Q10value Cinnamomum camphora plantation