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Aboveground carbon sequestration of Cunninghamia lanceolata forests:Magnitude and drivers

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Forest Ecosystems 2024年第1期11卷 32-41页

作者： Chen Wang Shuguang Liu Yu zhu Andrew R.Smith Ying Ning deming Deng National Engineering Laboratory for Applied Technology of Forestry&Ecology in South China Central South University of Forestry and TechnologyChangsha 410004China Technology Innovation Center for Ecological Conservation and Restoration in Dongting Lake Basin Ministry of Natural ResourcesChangsha 410007China College of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004China School of Ecology and Environment Hainan UniversityHaikou 570228China School of Natural Sciences Bangor UniversityGwyneddLL572UWUK College of Forestry Central South University of Forestry and TechnologyChangsha 410004China Hunan Prospecting Designing&Research General Institute for Agriculture Forestry&IndustryChangsha 410007China

Understanding the spatial variation,temporal changes,and their underlying driving forces of carbon sequestration in various forests is of great importance for understanding the carbon cycle and carbon management *** carbon density and sequestration in various Cunninghamia lanceolata forests,extensively cultivated for timber production in subtropical China,vary with biodiversity,forest structure,environment,and cultural factors remain poorly explored,presenting a critical knowledge gap for realizing carbon sequestration supply potential through *** on a large-scale database of 449 permanent forest inventory plots,we quantified the spatial-temporal heterogeneity of aboveground carbon densities and carbon accumulation rates in Cunninghamia lanceolate forests in Hunan Province,China,and attributed the contributions of stand structure,environmental,and management factors to the heterogeneity using quantile age-sequence analysis,partial least squares path modeling(PLS-PM),and hot-spot *** results showed lower values of carbon density and sequestration on average,in comparison with other forests in the same climate zone(i.e.,subtropics),with pronounced spatial and temporal ***,quantile regression analysis using carbon accumulation rates along an age sequence showed large differences in carbon sequestration rates among underperformed and outperformed forests(0.50 and 1.80 Mg·ha^(-1)·yr^(-1)).PLS-PM demonstrated that maximum DBH and stand density were the main crucial drivers of aboveground carbon density from young to mature ***,species diversity and geotopographic factors were the significant factors causing the large discrepancy in aboveground carbon density change between low-and high-carbon-bearing *** analysis revealed the importance of culture attributes in shaping the geospatial patterns of carbon *** work highlighted that retaining largesized DBH trees and increasing shade-t

关键词： Carbon density Carbon accumulation rate Forest age Spatial variation Cultural influence

Weak type heterodimensional cycle bifurcation with orbit-flip

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Science China Mathematics 2011年第6期54卷 1175-1196页

作者： lu qiuying zhu deming GENG FengJie Department of Mathematics Zhejiang Sci- Tech University Hangzhou 310018 China Department of Mathematics East China Normal University Shanghai 200241 China School of Information Engineering China University of Geosciences Beijing 100083 China

In this paper, we study the weak type heterodimensional cycle with orbit-flip in its non-transversal orbit by using the local moving frame approach. For the first two subcases, we present the sufficient conditions for the existence, uniqueness and non-coexistence of the homoclinic orbit, heteroclinic orbit and periodic orbit. Based on the bifurcation analysis, the bifurcation surfaces and the existence regions are located. And for the third subcase, we theoretically established both the coexistence condition for the homoclinic loop and the periodic orbit and the coexistence condition for the persistent heterodimensional cycle and multiple periodic orbits due to the weak type of the transversal heteroclinic orbit. Moreover, an analytical example is presented for this subcase.

关键词： local moving frame weak heterodimensional cycle orbit-flip

1982—2020年乌兰县植被NPP时空动态特征及驱动力量化分析

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农业工程学报 2024年第3期40卷 328-334页

作者：刘辉宋孝玉王荣荣祝德名何希刘斯琪西安理工大学省部共建西北旱区生态水利国家重点实验室西安710048 河南大学土木建筑学院开封475004

气候变化和人类活动对植被NPP(net primary productivity,净初级生产力)的驱动作用是全球气候变化背景下的研究热点,并且在不同的时空尺度上尚不能达成共识。中国西北寒旱牧区植被生态系统脆弱,对气候变化和人类活动的响应十分敏感,该... 详细信息

气候变化和人类活动对植被NPP(net primary productivity,净初级生产力)的驱动作用是全球气候变化背景下的研究热点,并且在不同的时空尺度上尚不能达成共识。中国西北寒旱牧区植被生态系统脆弱,对气候变化和人类活动的响应十分敏感,该研究以青海省乌兰县作为代表性研究区,采用GIMMS-NDVI and MOD-NDVI数据融合构建了长时序归一化植被指数(normalized difference vegetation index,NDVI)数据集,并结合CASA(carnegie-ames-stanford approach)模型获取了研究区1982—2020年植被生长季NPP,利用Sen+MK趋势分析方法探究了研究区植被生长季NPP的时空演变特征,同时采用构建的ADE+Sen量化归因方法对多种气候要素和人类活动的驱动作用进行了定量分析。结果表明,研究区植被生长季NPP多年均值为(205.9±11.5)g/(m^(2)·a)(以C计),年际变化无显著趋势,不同植被类型的生长季NPP年际波动过程与全域生长季NPP基本一致。在空间上,植被生长季NPP自西向东逐渐增加,年际变化趋势具有明显的空间异质性,且整体以退化为主,平均变化率为-0.151 g/(m^(2)·a2),其中表现出严重退化和轻度退化的面积占比分别达到了31.7%和29.5%。气候变化主导的植被面积占比达85.2%,其贡献值的绝对平均值为1.025 g/(m^(2)·a2),约是人类活动贡献值绝对平均值的2倍,太阳辐射、降水量、平均气温和平均风速均是影响植被生长季NPP动态的主要气候因素。该研究表明研究区植被整体表现为退化状态,气候变化是导致该现象的主导驱动因素。研究结果可为中国西北寒旱牧区植被生态系统的可持续利用和保护提供参考。

关键词：净初级生产力气候变化人类活动定量分析乌兰县

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中国传统医药非物质文化遗产保护述评

南京中医药大学学报（社会科学版） 2024年第3期25卷 141-145,178页

作者：朱德明叶亮浙江中医药大学浙江中医药文化研究院浙江杭州310053 南京中医药大学学报编辑部江苏南京210023

阐述了我国非物质文化遗产的保护措施,介绍了传统医药非遗的申报条件及我国传统医药非遗保护取得的成效。指出我国现阶段传统医药非遗存在列入国家级非遗代表性项目名录数目偏少且分类不清,单位和个人对传统医药非遗保护与传承乏力,传... 详细信息

阐述了我国非物质文化遗产的保护措施,介绍了传统医药非遗的申报条件及我国传统医药非遗保护取得的成效。指出我国现阶段传统医药非遗存在列入国家级非遗代表性项目名录数目偏少且分类不清,单位和个人对传统医药非遗保护与传承乏力,传承人才缺乏,软硬传播平台和数字化建设不足等问题。提出要高度重视传统医药非遗的保护与传承工作,强化政策支持,加强对非遗项目的考核与评估,加强非遗传承人队伍建设,加快软硬传播平台、数字化建设,从而进一步促进和完善我国传统医药非遗保护与传承工作。

关键词：非物质文化遗产中医药非遗非遗传承非遗保护传承人

Bifurcation of Degenerate Homoclinic Orbits toSaddle-Center in Reversible Systems

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Chinese Annals of Mathematics,Series B 2008年第6期29卷 575-584页

作者： Xingbo LIU deming zhu Department of Mathematics East China Normal University Shanghai 200241 China

The authors study the bifurcation of homoclinic orbits from a degenerate homoclinic orbit in reversible system. The unperturbed system is assumed to have saddle-center type equilibrium whose stable and unstable manifolds intersect in two-dimensional manifolds. A perturbation technique for the detection of symmetric and nonsymmetric homoctinic orbits near the primary homoclinic orbits is developed. Some known results are extended.

关键词： Reversible system Homoclinic orbits Saddle-center Bifurcation

Bifurcation Analysis of the Multiple Flips Homoclinic Orbit

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Chinese Annals of Mathematics,Series B 2015年第1期36卷 91-104页

作者： Tiansi ZHANG deming zhu College of Science University of Shanghai for Science and Technology Department of Mathematics East China Normal University

A high-codimension homoclinic bifurcation is considered with one orbit flip and two inclination flips accompanied by resonant principal eigenvalues. A local active coordinate system in a small neighborhood of homoclinic orbit is introduced. By analysis of the bifurcation equation, the authors obtain the conditions when the original flip homoclinic orbit is kept or broken. The existence and the existence regions of several double periodic orbits and one triple periodic orbit bifurcations are proved. Moreover, the complicated homoclinic-doubling bifurcations are found and expressed approximately.

关键词： Orbit flip Inclination flips Homoclinic orbit Resonance

Codimension 3 Non-resonant Bifurcations of Rough Heteroclinic Loops with One Orbit Flip

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Chinese Annals of Mathematics,Series B 2006年第6期27卷 657-674页

作者： Shuliang SHUI deming zhu College of Mathematics Physics and Information Engineering Zhejiaag Normal University Jinhua 321004 Zhejiang China College of Sciences Shanghai University Shanghai 200436 China Department of Mathematics East China Normal University Shanghai 200062 China

Heteroclinic bifurcations in four dimensional vector fields are investigated by setting up a local coordinates near a rough heteroclinic loop. This heteroclinic loop has a principal heteroclinic orbit and a non-principal heteroclinic orbit that takes orbit flip. The existence, nonexistence, coexistence and uniqueness of the 1-heteroclinic loop, 1-homoclinic orbit and l-periodic orbit are studied. The existence of the two-fold or three-fold 1-periodic orbit is also obtained.

关键词： Bifurcation Heteroclinic loop Non-resonance Orbit flip Periodic orbit

Stability and Uniqueness of Periodic Orbits Produced During Homoclinic Bifurcation

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Acta Mathematica Sinica,English Series 1995年第3期11卷 267-277页

作者： zhu deming Department of Mathematics East China Normal University Shanghai

Under a generic assumption, the existence and the uniqueness of the periodic orbit generating from a homoclinic bifurcation are shown, and the dimensions of its stable and unstable manifolds are given. In the case of ... 详细信息

关键词： Homoclinic bifurcation Periodic orbit Stable manifolds Dimensions

Bifurcation of Homoclinic Orbits with Saddle-Center Equilibrium

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Chinese Annals of Mathematics,Series B 2007年第1期28卷 81-92页

作者： Xingbo LIU Xianlong FU deming zhu Department of Mathematics East China Normal University Shanghai 200062 China.

In this paper, the authors develop new global perturbation techniques for detecting the persistence of transversal homoclinic orbits in a more general nondegenerated system with action-angle variable. The unperturbed system is assumed to have saddlecenter type equilibrium whose stable and unstable manifolds intersect in one dimensional manifold, and does not have to be completely integrable or near-integrable. By constructing local coordinate systems near the unperturbed homoclinic orbit, the conditions of existence of transversal homoclinic orbit are obtained, and the existence of periodic orbits bifurcated from homoclinic orbit is also considered.

关键词： Local coordinate system Homoclinic orbit Bifurcation