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Chinese Geographical Science 2016年第4期26卷 495-507页

作者： ZHANG Jing LYU Zhipeng SHAO Siya LI Fangfang YANG Shengtian SONG Wenlong LI Wei LI Shun-jiang College of Global Change and Earth System Sciences Beijing Normal University School of Geography Beijing Normal University School of Environment Beijing Normal University

The effects of acid deposition on pine forest ecosystems in Longli of Guizhou Province, southwestern China are studied using indoor experiments and model simulations. Indoor experiments are designed to explore the aluminum toxicity on pine seedlings, and the long-term soil acidification model （LTSAM） and a terrestrial biogeochemistry model （CENTURY） are used to simulate the influences of acid deposition on pine forest ecosystems. The indoor experiment results of aluminum toxicishow that aluminum ions in solution limit plant growth and acid deposition enhances this effect by facilitating the release of aluminum ions from the soil. pine seedling bio- mass and root elongation decrease as the aluminum concentration increases. The results of model simulations show that the soil chemis- try varies significantly with different changes in acid deposition. When the acid deposition increases, the pH value in the soil solution decreases and the soil A13＋ concentration increases. The increased acid deposition also has negative impacts on the forest ecosystem, i.e., decreases plant biomass, net primary productivity （NPP） and net C02 uptake. As a result, the soil organic carbon （SOC） decreases be- cause of the limited supply of decomposition material. Thus acid deposition need be reduced to help protect the forest ecosystems.

关键词： acid deposition aluminum toxicity long-term soil acidification model (LTSAM) terrestrial biogeochemistry model(CENTURY) pine forest

Effect of forest fire on soil microbial biomass and enzymatic activity in oak and pine forests of Uttarakhand Himalaya, India

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Ecological Processes 2021年第1期10卷 394-407页

作者： Devanshi Singh Priyanka Sharma Ujjwal Kumar Achlesh Daverey Kusum Arunachalam School of Environment and Natural Resources Doon UniversityDehradunUttarakhand 248012India

Background:forest fire incidences in the Himalayan region of Uttarakhand,India are very common in *** and oak are the principal and dominant species of Himalayan subtropical forest and Himalayan temperate forest,*** vegetation influences the physicochemical and biological properties of soil and forest fire in pine and oak forests may have a different effect on the physicochemical and biological properties of ***,the present study was carried out to assess the impact of forest fire on soil microbial properties,enzymatic activity,and their relationship with soil physicochemical properties in the advent of forest fire in the pine and oak forests of the Garhwal region of Uttarakhand Himalaya,***:The soil microbial biomass carbon and nitrogen,soil basal respiration,and acid phosphatase activity decreased,whereas dehydrogenase activity increased at burnt sites of both forest *** overall change in soil microbial biomass carbon was 63 and 40%at the burnt oak forest and burnt pine forest,*** activity and acid phosphatase activity showed a strong positive correlation with soil organic matter(r=0.8)and microbial indices,*** ratio of soil microbial biomass carbon/nitrogen was reduced at burnt sites of both forest *** analysis results showed that fire had a significant impact on soil *** soil basal respiration was linked with macro-and micronutrients at burnt sites,whereas at control sites,it was linked with physicochemical properties of soil along with ***:forest fire had a significant impact on soil properties of both forest *** impact of forest fire on soil microbial biomass carbon was stronger in the oak forest than in the pine *** type influenced soil enzymatic activity at burnt *** bacterial community was dominated over fungi in burnt sites of both *** microbial indices can be used as a selective measure to assess

关键词： Microbial indices Soil enzymes Microbial biomass forest fire pine forest Oak forest

The relationships between selected soil properties and caesium-137 identify organic carbon,nitrogen and water soluble phenols as indicators of soil erosion processes in different forest stands

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Journal of forestry Research 2021年第6期32卷 2589-2598页

作者： Federico Romeo Paolo Porto Carmelo Mallamaci Adele Muscolo Department of Agriculture Mediterranea UniversityFeo di Vito89122Reggio CalabriaItaly

In the last few decades,the use of environmental radionuclides,particularly caesium-137(^(137)Cs),represented one of the most valid methods for estimating soil ***,the cost associated with the use of the equipment needed for radiometric analyses is still high and,for this reason,finding more easily measurable indicators can be *** is a strong correlation between^(137)Cs,organic carbon(OC),nitrogen(N)and water soluble phenols(WSP)exists,indicating the latter parameters as possible early indicators of soil *** on the above assumptions,the main purpose of this work is to identify specific soil chemical parameters able to indicate early triggering of soil ***,several soil parameters such as pH,electric conductivity(EC),WSP,OC,N and C/N have been evaluated against^(137)Cs and on a comparative *** addition,since the rate of soil erosion depends on the degree of coverage and canopy structure,two different tree species(Pinus nigra laricio *** Fagus sylvatica L.)have been considered in this contribution in which ten different scenarios of forest management have been *** results show that the reduction in tree cover of managed sites triggers erosion and nutrient loss *** has been observed that the loss of^(137)Cs,compared to the control areas,is closely correlated with those of WSP,OC and *** parameters(WSP,OC and N),more easily assessable,can be a valid tool to understand easily,triggering of erosive phenomena.

关键词： ^(137)Cs Erosion indicators forest thinning Beech forest pine forest

Deposition of litter and nutrients in leaves and twigs in different plant communities of northeastern Mexico

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Journal of forestry Research 2018年第5期29卷 1307-1314页

作者： Humberto González-Rodríguez Roque Gonzalo Ramírez-Lozano Israel Cantú-Silva Marco Vinicio Gómez-Meza Eduardo Estrada-Castillón José Ramón Arévalo Facultad de Ciencias forestales Universidad Autdnoma deNuevo Ledn Carr. Nac. No 85 km 145 67700 LinaresNuevo Ledn Mexico Facultad de Ciencias Bioldgicas Universidad Autdnoma deNuevo Ledn Ave. Universidad S/N Cd. Universitaria66451 San Nicolfis de los Garza Nuevo Ledn Mexico Facultad de Economla Universidad Autdnoma de NuevoLedn Monterrey Nuevo Ledn Mexico Departamento de Botanica Ecologiay Fisiologfa Vegetal Facultad de Ciencias Universidad de La LagunaCanary Islands Spain

Studies on litterfall and decomposition provide estimations of decomposition rates of different *** is key information to understanding ecosystem dynamics and changes in a scenario of global *** objective of this research was to assess litterfall production,the potential deposition of macro and micronutrients through leaf and twig fall as well as macronutrient—use efficiency in three forest ecosystems at different altitudes： a pine forest mixed with deciduous species（S1）; a Quercus ***（S2）; and,a Tamaulipan thornscrub forest（S3）.Total annual litterfall deposition was 594,742 and 533 g m^（-2） for S1,S2 and *** litter was higher （68%） than twigs（18%）,reproductive structures（8%） or miscellaneous material（6%）.Micronutrient leaf deposition was higher for Fe followed by Mn,Zn and *** leaf deposition was higher for Ca followed by K,Mg and *** though P deposition in leaves and twigs was lower than other macronutrients,its nutrient use efficiency was higher than Ca,Mg or *** and species composition determine litter and nutrient deposition,with higher values at mid-altitudes（550 m）.Altitude is an important factor to consider when analyzing litter production as well as nutrient deposition as shown in this *** production and nutrient deposition are expected to change in a scenario of global warming.

关键词： Deciduous species Litter deposition Leaf/twig litter nutrients pine forest Tamaulipan thornscrub

Theoretical derivation of risk-ratios for assessing wind damage in a coastal forest

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Journal of forestry Research 2002年第4期13卷 309-315,338页

作者：朱教君松崎健李凤芹権田豊中国科学院沈阳应用生态研究所沈阳中国110016 日本国立新泻大学农学部

Based on the discussion of relationships between thinning and wind damage, and published information, a method for estimating risk ratios of wind damage was developed. Estimations of risk-ratio for Pinus thunbergii trees and stands were de-duced from stem bending theory and coefficients characterizing wind profile, distribution of branches and optical stratification po-rosity. The results showed that if the value of constant b in the branch distribution-model equals the attenuation coefficient s in the wind profile model for a single tree crown, then the parameter H/D1.33 (height over stem diameter cubed) can be used to compare and evaluate the risk-ratio of wind damage for individual trees. The same method can be applied to stands using the coefficient of wind profile in a stand, i.e. attenuation coefficient , the coefficient from distributions of optical stratification porosity, i.e. extinction coefficient , and the parameter D1.33. The application of parameter H/D1.33 and the process of determining risk ra-tios of wind damage for stands were also given in the paper.

关键词： Wind damage Thinning pine forest Risk-ratio CLC number: S761.2 S757.1 Document code: A Article ID: 1007-662X(2002)04-309-07