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Accuracy of space-for-time substitution for vegetation state prediction following shrub restoration

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Journal of Plant Ecology 2018年第2期11卷 208-217页

作者： Renhui Miao Xueli Qiu Meixia Guo ala musa Deming Jiang International Joint Research Laboratory for Global Change Ecology College of Life SciencesHenan UniversityKaifeng 475004China Graduate School of the Chinese Academy of Sciences Beijing 100049China

Aims:Space-for-time substitution(SFT)is often used for vegetation status estimation during the recovery process of ***,the evaluated accuracy of SFT remains *** eight-year located observation was used to assess the validity of SFT for vegetation state ***:This study analyzed a chronosequence of Caragana microphylla *** using the located observation method to test the accuracy of SFT for vegetation state prediction in the mobile sand dunes of the Horqin Sandy Land in northeastern China from July 2005 to June *** Findings:According to SFT,simple vegetation parameters(density,coverage and biomass)were found to be unstable,while sophisticated veg-etation parameters(species diversity and evenness)were relatively stable across the experimental treatments during the study ***,both the simple and sophisticated parameters were found to be relatively stable when tested using the located obser-vation ***,most simple vegetation parameters slightly increased,while sophisticated parameters slightly decreased after eight years of field ***,long-term restoration management facilitated improvements in the simple parameters,but may have adversely impacted the sophisticated parameters in the post-restoration *** results suggest that sophisticated vegetation parameter states can be predicted by SFT,while simple vegetation parameter states are not well predicted by *** conclusion,located observations or other effective evaluation methods must be employed to offset the deficiency of the SFT method for the prediction of vegetation parameters.

关键词： community structure desertification location observation restoration stability

The feasibility of using soil seed bank for natural regeneration of degraded sandy grasslands

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International Soil and Water Conservation Research 2022年第3期10卷 414-421页

作者： Yongcui Wang Lei Chu Zhimin Liu musa ala Jixiang Lin Jianqiang Qian Quanlai Zhou Lixin Wang CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang110016China Institute of Applied Ecology Chinese Academy of SciencesShenyang110016China Department of Horticulture and Landscape Architecture Purdue UniversityWest LafayetteIN47907USA College of Landscape Architecture Northeast Forestry UniversityHarbin150040China College of Forestry Henan Agricultural UniversityZhengzhou450002China Department of Earth Sciences Indiana University-Purdue University Indianapolis(IUPUI)IndianapolisIN46202USA

Desertification in degraded grasslands is manifested through the development of bare sandy patches,which eventually lead to habitat *** ability of these bare sandy patches to regenerate naturally through in-situ soil seed banks is not well *** fill this knowledge gap,we randomly selected 24 bare sandy patches with areas ranging from 19 to 898 m^(2) in a desertified grassland of the Horqin sandy land,Northern China to determine whether soil seed bank can be used for natural regeneration of bare sandy *** composition and density of soil seed bank as well as aboveground vegetation composition,abundance and coverage were *** then determined their relationships with in-situ habitat *** observations showed that the studied area had low soil seed bank density and species richness,as well as depauperate soil seed bank ***,local soil seed bank was not able to provide sufficient seed source for natural *** was indicated by the relationships between aboveground vegetation,soil seed bank and the in-situ habitat *** bare patches with an area between 300 m^(2) and 900 m^(2),increase the soil seed bank density and species richness should be the main restoration *** bare patches with a small area of less than 50 m^(2),restoration of vegetation density should be the main *** data highlighted that different extents of desertification,indicated by different bare patches,are requiring distinct restoration measures.

关键词： Degradation In-situ Restoration Seed bank Semi-arid

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沙丘土壤含水量与地下水埋深时空变化特征

干旱区研究 2020年第6期37卷 1427-1436页

作者：张圆浩阿拉木萨印家旺蒋绍妍中国科学院沈阳应用生态研究所辽宁沈阳110016 中国科学院大学北京100049 辽宁林业职业技术学院辽宁沈阳110101

干旱半干旱沙丘区降水稀少,蒸发量大,水资源状况是其生态系统运行的关键因素。沙丘区土壤含水量及地下水是其水资源状况的关键衡量指标,本研究依据植被盖度梯度,在沙丘区选取典型沙丘(流动沙丘、半固定沙丘、固定沙丘)为研究对象,开展... 详细信息

干旱半干旱沙丘区降水稀少,蒸发量大,水资源状况是其生态系统运行的关键因素。沙丘区土壤含水量及地下水是其水资源状况的关键衡量指标,本研究依据植被盖度梯度,在沙丘区选取典型沙丘(流动沙丘、半固定沙丘、固定沙丘)为研究对象,开展了不同植被盖度下和不同沙丘坡位的土壤水分含量和地下水埋深变化特征研究。结果表明:(1)沙丘植被盖度影响沙丘土壤含水量,随着植被盖度的增高,沙丘土壤水分含量逐渐降低,表现为土壤水分含量顺序为:流动沙丘>半固定沙丘>固定沙丘。沙丘不同坡位土壤水分含量存在差异,表现为:迎风坡底>背风坡底>迎风坡中>丘顶>背风坡中的趋势。沙丘土壤水分的时间变化特征主要受到降雨过程的控制,呈现出与降雨发生特征的一致性。(2)沙丘区地下水位季节性变化表现出非生长季明显回升,生长季逐渐下降的趋势,年度变化范围-0.21~0.18 m之间。植被盖度影响沙丘区地下水位的变化特征,变异系数由大到小为:固定沙丘>半固定沙丘>流动沙丘;受降雨影响,当短时间内累积降雨量或者单次降雨量超过30 mm时,沙丘区地下水位表现出对应的回升,回升幅度受到沙丘表面植被盖度和坡位的影响而呈现差异。(3)地下水可能对沙丘坡底位置深层土壤水分进行补给,但对沙丘坡中及以上区域土壤水分未见明显补给作用。

关键词：沙丘植被盖度沙丘坡位土壤含水量地下水埋深

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科尔沁沙地沙丘植被对丘间低地水体的影响

中国沙漠 2022年第6期42卷 194-203页

作者：印家旺阿拉木萨苏宇航中国科学院沈阳应用生态研究所辽宁沈阳110016 中国科学院大学北京100049

在流动沙丘以建立固沙植被的方式向固定沙丘转化的过程中,植被将改变沙丘水分再分配过程,影响沙丘的水文调节功能,甚至可能引起沙丘生态系统水资源失衡。为探明植被对沙丘水文调解功能的影响,以科尔沁沙地不同植被盖度的沙丘-丘间地水... 详细信息

在流动沙丘以建立固沙植被的方式向固定沙丘转化的过程中,植被将改变沙丘水分再分配过程,影响沙丘的水文调节功能,甚至可能引起沙丘生态系统水资源失衡。为探明植被对沙丘水文调解功能的影响,以科尔沁沙地不同植被盖度的沙丘-丘间地水体组合体为研究对象,于2021年生长季开展了沙丘植被盖度、丘间低地水体变化特征、气象因素的动态观测,以期明确沙丘植被变化对丘间低地水体的影响。结果表明:(1)沙丘植被盖度影响沙丘水分对外补给能力,随着沙丘表面固沙植被盖度增加,单位面积沙丘对外水分补给能力降低,表现为流动沙丘(58.25 mm)>半固定沙丘(24.75 mm)>固定沙丘(14.87 mm),占同期降水量的比例分别为21.39%、9.09%、5.46%。(2)生长季流域降水补给量、植被盖度、气温显著影响沙丘对丘间低地水体的水分补给量,丘间低地水体获补量与流域降水补给量显著正相关,与植被盖度、气温极显著负相关。(3)依据水量平衡原理推导出沙丘水分对外补给量(Y)与影响因素(降水补给量X_(1),植被盖度X_(2),平均气温X_(3))的关系模型,Y=1052.737+0.1X_(1)-11.459X_(2)-37.585X_(3),R2=0.641。可根据模型预测沙丘水分对外补给量,为流动沙丘生物治理模式的合理选择提供支持。

关键词：沙地水分运移植被盖度降水补给水量平衡

科尔沁沙地不同土地利用类型土壤入渗特征比较研究

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水土保持通报 2022年第4期42卷 90-98页

作者：印家旺阿拉木萨苏宇航蒋绍妍中国科学院沈阳应用生态研究所辽宁沈阳110016 中国科学院大学北京100049 辽宁生态工程职业学院辽宁沈阳110101

[目的]探究科尔沁沙地不同土地利用类型土壤入渗特征的差异,为干旱—半干旱区包气带水分与物质运移等相关研究提供科学参考。[方法]利用双环入渗仪野外实测和室内土壤物理性质分析相结合的方法,研究了科尔沁沙地具有代表性的8种土地利... 详细信息

[目的]探究科尔沁沙地不同土地利用类型土壤入渗特征的差异,为干旱—半干旱区包气带水分与物质运移等相关研究提供科学参考。[方法]利用双环入渗仪野外实测和室内土壤物理性质分析相结合的方法,研究了科尔沁沙地具有代表性的8种土地利用类型(樟子松林地、小叶锦鸡儿林地、白柠条林地、撂荒草地、草甸草地、疏林草地、玉米农田以及裸沙地)土壤入渗特征及其影响因素,同时采用Kastiakov模型、Horton模型、Philip模型和G-P综合模型对其水分入渗过程进行了拟合,比较其拟合优度。[结果](1)不同土地利用类型土壤入渗特征存在显著差异,初始入渗率变化范围为1.595~12.020 mm/min,由大到小依次为:裸沙地>白柠条林地>玉米农田>樟子松林地>小叶锦鸡儿林地>草甸草地>撂荒草地>疏林草地;15 min入渗率变化范围为0.617~3.690 mm/min,由大到小依次为:裸沙地>白柠条林地>樟子松林地>小叶锦鸡儿林地>玉米农田>撂荒草地>草甸草地>疏林草地;土壤稳定入渗率变化范围为0.576~3.495 mm/min,由大到小依次为:裸沙地>白柠条林地>玉米农田>小叶锦鸡儿林地>樟子松林地>撂荒草地>草甸草地>疏林草地;(2)不同土地利用类型入渗率与土壤容重、细砂含量呈极显著负相关,与中砂含量呈极显著正相关;稳定入渗率与非毛管孔隙度呈显著正相关;(3)各模型对科尔沁沙地土壤入渗过程的拟合优度依次为:Horton模型>G-P综合模型>Kastiakov模型>Philip模型,其中Horton模型决定系数最高且相对误差最小,能更准确地模拟科尔沁沙地土壤入渗的实际情况。[结论]科尔沁沙地不同土地利用类型土壤入渗特征存在差异,土壤性质对其入渗特征影响显著;Horton模型在科尔沁沙地拟合度较高,可应用此模型来估算水分入渗过程。

关键词：科尔沁沙地不同土地利用类型水分入渗入渗模型模型拟合

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Comparative seismic design optimization of spatial steel dome structures through three recent metaheuristic algorithms

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Frontiers of Structural and Civil Engineering 2022年第1期16卷 57-74页

作者： Serdar CARBAS musa ARTAR Department of Civil Engineering Karamanoglu Mehmetbey UniversityKaraman 70200Turkey Department of Civil Engineering Bayburt UniversityBayburt 69000Turkey

Steel dome structures,with their striking structural forms,take a place among the impressive and aesthetic load bearing systems featuring large internal spaces without internal *** this paper,the seismic design optimization of spatial steel dome structures is achieved through three recent metaheuristic algorithms that are water strider(WS),grey wolf(GW),and brain storm optimization(BSO).The structural elements of the domes are treated as design variables collected in member *** structural stress and stability limitations are enforced by ASD-AISC ***,the displacement restrictions are considered in design *** metaheuristic algorithms are encoded in MATLAB interacting with SAP2000 for gathering structural reactions through open application programming interface(OAPI).The optimum spatial steel dome designs achieved by proposed WS,GW,and BSO algorithms are compared with respect to solution accuracy,convergence rates,and reliability,utilizing three real-size design examples for considering both the previously reported optimum design results obtained by classical metaheuristic algorithms and a gradient descent-based hyperband optimization(HBO)algorithm.

关键词： steel dome optimization water strider algorithm grey wolf algorithm brain storm optimization algorithm hyperband optimization algorithm

EFFECT OF THE COMPOSITION OF m-CRESOL/H_2O SOLVENT ON HYDRODYNAMIC PROPERTIES OF NYLON 6

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Chinese Journal of Polymer Science 2006年第4期24卷 369-377页

作者： musa Kaleem Baloch Mohsan Nawaz Department of Chemistry

The intrinsic viscosity [η], Huggins constant （Ku）, [η]0, α^3 and flow activation energy values of nylon 6 have been measured in wateηm-cresol （0/100-20/80） systems at different temperatures （20-60℃）. It has been found that the intrinsic viscosity, [η]0 and α^3 increase with the increase in water contents in m-cresol up to 15% and then decrease. They increase with the increase in temperature irrespective of solvent composition. It has been noted that the percent increase of α^3 is the highest at 60℃ and the lowest at 20℃ for a particular solvent system. The intrinsic viscosity data obey Arrhenius equation over the considered conditions. The activation energy and the KH values decrease very sharply with the addition of water, giving a minimum value at 15% of water and then increase slowly. The variation of all the parameters has been explained in terms of variation in thermodynamic quality of solvent with the addition of water to m-cresol and change in temperature, resulting in the change of conformational and orientational properties of polymer molecules. This change of solvent quality also results in variation of selective sorption of solvent over the polymer, such as hydrogen bonding, etc.

关键词： Intrinsic viscosity Huggins constant Thermodynamic quality of solvent Activation energy Hydrogen bonding Conformation Selective sorption.

Monte Carlo Study of CO-NO Catalytic Surface Reaction Including CO-CO Repulsion

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Chinese Physics Letters 2006年第4期23卷 1034-1037页

作者： Waqar Ahmad musa Kaleem Baloach Physics Research Division Pakistan Institute of Nuclear Science and Technology PO Nilore Islamabad Pakista Department of Chemistry Gomal University D.I. Khan Pakistan

The CO-NO reaction on a catalytic surface is studied by using Langmuir-Hinshclwood thermal mechanism with Monte Carlo computer simulation. In this model, a novel concept of CO CO repulsion is introduced, which has experimental evidence due to the formation of dipoles when these molecules are chemisorbed on the surface. The system is investigated by applying two approaches of NO dissociation. In the first ***, NO always decomposes into N and O before adsorption on the surface, In the second case, NO adsorbs on the surface molecularly and then dissociates into N and O if a vacancy is present in its adjacent neighbourhood. The steady state reactive window （i.e. the continuous production of CO2 and N2） is obtained only with the diffusion of N-atoms on the surface, which extends with CO-CO repulsion in the first, case. Itowever, in the second case, reactive window is obtained with CO-CO repulsion alone, The reactive window width in this case is reasonably large. The first-order phase transition is eliminated in both the cases with CO-CO repulsion.

关键词： KINETIC PHASE-TRANSITIONS SQUARE LATTICE HEXAGONAL SURFACES REACTIONMODEL NITRIC-OXIDE SIMULATION MECHANISM

Miscibility between PS and PSAN Affected by Solvent and Temperature of the System

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Chinese Journal of Polymer Science 2014年第11期32卷 1442-1449页

作者： Zafarullah Khan Marwat musa Kaleem Baloch Department of Chemistry Gomal University Dera Ismail Khan Khyber PakhtoonkhwaPakistan

The influence of solvent on the miscibility of polystyrene（PS） and poly（styrene-co-acrylonitrile）（PSAN） blends has been investigated viscometrically. The miscibility of different PS/PSAN blend（30/70, 50/50 and 70/30） compositions in acetone and benzene at 20, 30, and 40 °C was investigated on the basis of the sign of Chee（ΔB and ）, and Sun’s（α） criteria. The values of these parameters were evaluated from the analyses of reduced viscosity data of binary（solvent/polymer） and ternary（solvent/polymer1/polymer2） polymer systems. These investigations indicated partial miscibility for both the blend systems. However, PS/PSAN/acetone blend system showed somewhat higher partial miscibility than the PS/PSAN/Benzene blend system highlighting the impact of solvent over the polymer-polymer interactions and hence their miscibility. The results obtained through viscometry were also corroborated by the refractive index and density results for the blends under study. The effect of temperature on miscibility in both the cases was almost negligible.

关键词： Miscibility Polystyrene Poly(styrene-co-acrylonitrile) Viscosity Density Refractive index.