Carbon Stock of Larch Plantations and Its Comparison with an Old-growth Forest in Northeast China

The overall goal of this study was to understand carbon(C) stock dynamics in four different-aged Japanese larch(Larix kaempferi) plantations in Northeast China that were established after clear-cutting old-growth Korean pine deciduous forests. Four Japanese larch plantations which were at 10, 15, 21, and 35 years old and an old-growth Korean pine deciduous forest which was 300 years old in Northeast China were selected and sampled. We compared the C pools of biomass(tree, shrub and herb), litterfall(LF), and soil organic carbon(SOC) among them. The biomass C stock of larch plantation at 10, 15, 21, and 35 years old was 26.8, 37.9, 63.6, and 83.2 Mg/ha, respectively, while the biomass C stock of the old-growth Korean pine deciduous forest was 175.1 Mg/ha. The SOC stock of these larch plantations was 172.1, 169.7, 140.3, and 136.2 Mg/ha respectively, and SOC stock of 170.4 Mg/ha in the control of old-growth forest. The biomass C stock increased with stand age of larch plantations, whereas SOC stock decreased with age, and C stock of LF did not change significantly(P > 0.05). The increase of biomass C offset the decline of SOC stock with age, making total carbon stock(TCS) of larch plantations stable from stand ages of 10–35 years. The TCS in larch plantations was much smaller than that in the old-growth forest, suggesting that the conversion of old-growth forests to young larch plantations releases substantial C into the atmosphere.

Structure and floristic composition of old-growth wet evergreen forests of Nelliampathy Hills, Southern Western Ghats

We analyze the structure and composition of old-growth wet evergreen forest of Nelliampathy hills, the chain of hills lying immediately south of Palghat Gap, in the southern Western Ghats of India. We sampled 30 plots of 0.1 ha each （50 m × 20 m） at six locations enumerating all plants ？ 10 cm girth at breast height. We pooled the data and computed various structural parameters. There were 152 species of 120 genera and 51 families of the study area. Of these, 118 （77%） were trees, 24 were climbers （16%） and 10 were shrubs （7%）. Species richness varied from 58–99 per 0.5 ha sample and Shannon indices of diversity ranged from 4.4 to 5.2. Fifty-nine per cent （89 species） of the species were Indian Sub-continent elements and 34% （51 species） are endemic to the Western Ghats. Fifteen species are listed in various threat categories. Aglaia and Litsea were the most species-rich genera. Numbers of families ranged from 27–43 per 0.5 ha sample. Euphorbiaceae and Lauraceae were the most species-rich families. Stand density varied from 1714 to 2244 stems·ha？1 and basal area from 53.6 to 102.1 m2·ha？1. The vegetation was dominated by 3–6 species and six dominance patterns characterized the species composition within the hill complex. The old-growth evergreen forests of Nelliampathy exist as small fragments rich in biodiversity and can be used as benchmarks for comparison with disturbed forests.

COMPETITION IN OLD GROWTH KOREAN PINE FOREST

Korean pine(Pinus koraiensis) interspecilic competition and intraspecifie companioned with other species competition in old growth Korean pine forest in northeast China were studied using Hegyi's competition index model for individual tree.The results show that differences of competitive intensity exist in interspecific and intraspecific for Korean pine with an order of intraspecific ＞Abies nephrolepis Picea koraiensis Tilia amurensis Betula costat＞Acer mono ＞Ulnuts propinqua＞Populus davidiana,and that relationship of competitive index to indivdual size (in DBH) of objective tree follows closely multiplieate eqtuation and that competitive intensity gradually reduces with inereasing of individual size of objective tree, but it is tending towards stability after individual of objective tree inerease to specified size (DBH about 20 cm).It provided a serviceable approach for researches of intraspecific relationship in population ecology.

MORE ATTENTION TO PROTECTION AND RESEARCH ON OLD-GROWTH KOREAN PINE (PINUS KORAIENSIS) FORESTS

This paper reviews the researches on old-growth korean pine (Pinus koraoensis) forest in Northeast China. The ecological characteristies of the forest were summarized. According to the researeh results, the importance of studying and reserving on the old-growth forest was addressed, which were the indispensable research laboratory and classroom for forest managers. The conelusions indicate that the future of Korean pine forest management should be based on the research results of oldgrowth forests.

AGE STRUCTURE AND SPATIAL PATTERN OF OLD-GROWTH KOREAN PINE FOREST IN XIAOXING'ANLING MOUNTAIN

Spatial pattern of trees, basal stem increment and height were examined in a 5.0 ha mixed deciduous/ Pinus koraiensis forest from October in 1984 to May in 1987. Conclusions arc as following: 1. Analysis of the age-structure of the korcan pine forest shows that it is different from general steady-state forest type. The lack of saplings and individuals in small-diameter class clearly indicates that regeneration is not continuous. Continuous regeneration depends on thinning of the canopy to form a gap. Similar-aged korcan pine seedings grow in these gaps. 2. The horizontal structure of the korcan pine is a mosaic of more or less even-aged groups of trees. The mosaic is a result of korcan pine by regeneration strategy. The aggregations of korcan pine of different ages overlaps to form a continuous population generation. As a results, the population is maintained in steady state.

喀斯特栎类老龄林的空间结构分析

[目的]研究喀斯特栎类老龄林的分布格局、空间关联和标记特征,探明垂直分层在喀斯特森林生物多样性维系中的作用。[方法]在中国西南地区南盘江流域的喀斯特老龄林(>300 a)中建立1块面积为200 m×110 m的固定样地,依据树高和物种组分将树木划分为林分上层和林分下层,用负指数函数分析了径阶与物种多度和丰富度的数量关系,用双相关函数g(r)分析林分上层、林分下层以及它们各自主要种群的分布格局和空间关联,用标记相关函数kmm(r)分析树种和树木大小的空间分布。[结果](1)林分、林分上层和林分下层的径阶分布均呈倒J型,林分和林分下层的物种丰富度随径阶的增大而减小,而林分上层则呈先升后降的趋势;(2)林分上层在多数尺度上呈规则或随机分布,仅在小尺度(r=0~1 m、4~6 m)上表现为聚集分布,林分下层的聚集强度和尺度皆大于林分上层;(3)林分上层和林分下层之间,以及它们各自的主要种群之间均以随机关联为主,只有个别种间对在小尺度(r=0~2 m)上呈正关联或负关联;(4)林分和林分下层在所有观测尺度上表现为同种聚集,强度明显大于林分上层;林分和林分上层的个体大小分化明显,小径木聚集。林分下层的个体大小相近,在多数尺度上混生。[结论]垂直分层决定了林分上层、林分下层的物种组分、多度、分布格局和空间关联,在物种共存和多样性维持中扮演重要角色。

景迈山古茶林对村落地方性的重构——以芒景村为例

基于生态与经济的视角,本研究利用人文主义与结构主义对景迈山芒景村的地方性重构过程进行了分析,探究物质在地方性重构与人的主体实践之间的互动机制。结果显示,古茶林的社会意义随着社会的发展产生演变,并通过主体的文化实践与社会系统相互影响、共同演化,显示出物质这一实体承载的社会意义的动态性。然而,社会意义实践的主体又是多元的,在利益上存在着冲突、博弈与妥协,这使得地方性在重构的过程中充满了不确定性。在他者的表征过程中,古茶林经历了从低产、落后向生态、有机话语的转变;在地者通过历史想象,将物质的社会意义与民族文化记忆联结起来,对地方性进行着持续的建构与重塑,并以此为基础形成本民族的文化体系,从而重构了芒景村的地方性。

Stand age structural dynamics of conifer, mixedwood, and hardwood stands in the boreal forest of central Canada

To study the effects of stand development and overstory composition on stand age structure, we sampled 32 stands representing conifer, mixedwood, and hardwood stand types, ranging in ages from 72 to 201 years on upland mesic sites in northwestern Ontario. We defined the stages of stand development as: stem exclusion/canopy transition, canopy transition, canopy transition/gap dynamics, and gap dynamics. Stand age structure of conifer stands changed from bimodal, bimodal, reverse-J, and bimodal, respectively, through the stages of stand development. Mixedwood and hardwood stands revealed similar trends, with the exception of missing the canopy transition/gap dynamic stage in mixedwoods. Canopy transition/gap dynamic stage in hardwoods showed a weaker reverse-J distribution than their conifer counterparts. The results suggest that forest management activities such as partial and selection harvesting and seed-tree systems may diversify standard landscape-level age structures and benefit wildlife, hasten the onset of old-growth, and create desired stand age structures. We also recommend that the determination of old-growth using the following criteria in the boreal forest: 1) canopy breakdown of pioneering cohort is complete and stand is dominated by later successional tree species, and 2) stand age structure is bimodal, with dominating canopy trees that fall within a relatively narrow range of age and height classes and a significant amount of understory regeneration.

景迈山古茶林文化景观遗产价值认知的过程与思考

基于遗产价值认知的建构性质,文章通过分析2012年以来景迈山古茶林申遗文本内容的变化,提出景迈山遗产价值的认知和思考是一个不断趋于完善和深化的过程。这其中既体现出国际权威话语体系对世界遗产“突出普遍价值”及真实性、完整性的建构,也包括国家性、民族性和地方性视角对遗产价值内涵的文化自信反馈,具体反映在遗产名称、遗产要素、遗产范围、突出普遍价值及真实性完整性等内容上。遗产价值描述的历次修订充分展现了对景迈山遗产资源特征认识的不断深入,同时彰显了我国30余年来在遗产申报、保护与管理工作中逐渐显现的文化自信,也对我国未来遗产申报的价值认知与建构具有启示意义。

Resilience of Bottomland Hardwood Stands Following Agricultural Use on the Santee Experimental Forest

Resilience is a key function that affects an ecosystem’s ability to recover from disturbance. Understanding the extent to which forest communities recover after a long period of disturbance without direct intervention is important to provide context for considering ecosystem response to disturbance regimes. Species composition and structure were recorded on bottomland hardwood stands that were once inland and freshwater tidal rice fields. We sampled 17 old-field sites and 7 reference sites across three geomorphic settings. The old-field sites ranged from 30 to 120 years since agricultural abandonment. A total of 89 species were found across the old field sites and reference sample areas. Of that total, trees comprised 33 species, shrubs—5 species, and vine/herbs/forbs—51 species. Using field data, combined with stand inventory records, aerial photography (1936-2010), and high-resolution LiDAR imagery, we chronicled the evolution of the forest since the cessation of agriculture. Our findings demonstrate how Pinus taeda seeded directly after the rice fields went to fallow;and this conversion of bottomland swamp to rice to pine was a direct result of water management embankments constructed across the landscape to aid in crop irrigation. The remnant water management features may still alter flooding patterns thereby affecting development of Taxodium distichum and Nyssa aquatica in the old-fields. These results suggest, that over the 100+ years forest stands on the Santee Experimental Forest have developed to represent bottomland hardwoods characteristic of the southeastern United States coastal plain.

郑州市新、老城区暴雨内涝灾害风险指标重要性分析

为探究影响城市暴雨内涝灾害风险的评价指标及各指标的重要性,以郑州市高新区和金水区作为新、老城区的代表,建立了涵盖自然要素和社会要素的风险指标评价体系,并利用随机森林模型分别确定了各评价指标对新、老城区暴雨内涝灾害影响的重要程度。结果表明,对于新、老城区来说,孕灾环境敏感性均是最重要的一级指标,其中,不透水率、管道密度分别是地表、地下孕灾环境最重要的三级指标;致灾因子危险性对于金水区和高新区的重要性最低,且雨量的重要性远大于雨型;新、老城区的差异主要体现在承灾体稳定性,其对于金水区、高新区的重要性分别为0.23、0.09。结果可为郑州市暴雨内涝灾害的防治提供一定参考。

普洱景迈山古茶林文化景观世界遗产申报回顾与总结

鉴于景迈山古茶林资源特点以及文化景观遗产特性,自2011年开展申遗工作以来,该项目陆续经历了准备期、发展期、整治期和迎评期4个发展阶段,各阶段重点任务明晰。回顾漫长申遗历程,以下经验值得借鉴,即系统挖掘世居民族历史文化价值,同时统筹可持续发展的时代需求;建立管理机构,制定管理法规,依法依规加强遗产地科学管理;积极开展遗产教育与公众参与,注重价值传播与经验交流。

海岛大径级树木健康评价指标体系构建——以上海大金山岛为例

大径级树木是维持森林群落结构稳定性的主体。海岛由于特殊的生物地理环境蕴育着数量可观的大径级树木。本文以上海大金山岛168株大径级树木为对象,调查了影响树木生长的生物和非生物因素,根据敏感性分析筛选出12个反映海岛大径级树木健康的关键指标;利用层次分析法构建了海岛大径级树木健康评价指标体系,并评价每株个体的健康程度。结果显示:(1)大金山岛大径级树木中,25株为古树,37株为古树后续资源。朴树(Celtis sinensis Pers.)、桑(Morus alba L.)、麻栎(Quercus acutissima Carr.)和乌桕(Triadica sebifera(L.)Small)是上海市现存的最大古树;山合欢(Albizia julibrissin Durazz.)、野鸦椿(Euscaphis japonica(Thunb.ex Roem.et Schult.)Kanitz)、红楠(Machilus thunbergii Siebold et Zucc.)、鸡桑(Morus australisPoir.)、豆梨(Pyrus calleryanaDecne.)、柃木(Eurya nitidaKorth.)、青冈(Cyclobalanopsis glauca(Thunb.)Oerst.)是未纳入上海市古树名录中的最大古树。(2)指标体系中,准则层权重大小为生物因素>立木状况>生长环境;指标层中叶片病害程度、攀援藤本盖度、树干病害程度、邻体空间挤压程度和枯枝比权重较大,各占约10%。(3)54%的大径级树木存在不同程度的健康问题。豆梨、楝(Melia azedarach L.)、丝棉木(Euonymus maackii Rupr.)、构树(Broussonetia papyrifera(L.)L’Hér.ex Vent.)、白檀(Symplocos paniculata(Thunb.)Miq.)、野鸦椿、黄檀(Dalbergia hupeana Hance)和算盘子(Glochidion puberum(L.)Hutch.)的健康状况相对较差。

新农保参与行为与退耕还林还草:理论分析与实证检验

退耕还林还草工程实施的主要阻力之一是补贴结束后,农民生计受到挑战时所面临的复耕风险,新农保的施行弱化了土地经济保障功能,有可能促进农民自发、永久性退耕还林还草。首先,基于效用论,构建了新农保作用农民退耕还林还草行为的理论分析框架;其次,基于农业农村部农村经济研究中心全国农村固定观察点18789份数据,运用Probit模型实证分析了新农保对农民退耕还林还草行为的影响;最后,运用基于聚类稳健标准误的logistic回归模型进行稳健性检验。结果显示:①新农保增加预期收入,退耕还林还草减少预期收入,但退耕还林还草后多出来的闲余时间增加了农民效用。基于效用论所构建的农户行为理论分析框架显示,农户参与新农保的行为影响到耕地面积数量,从而作用农户退耕还林还草行为。②农民参加新农保后,其采取退耕还林还草行为的可能性更高,新农保增加了农民年老时基本生活依赖的渠道,从而弱化了耕地的经济保障功能,一定程度上促进了农民参加退耕还林还草工程。③稳健性检验中,基于聚类稳健标准误的logistic回归模型仍然证实了“参加新农保有利于农民退耕还林还草”的结论。④健康状况越差的农户,采取退耕还林还草行为的可能性越低,健康状况差一般意味着医疗费开支大,未来收入面临较大不确定性,对耕地的依赖性强,从而不愿意退耕还林还草;年末生产性固定资产原值越大的农户,越有可能具有退耕还林还草行为。政策层面可以考虑将林区和牧区的“新农保”制度和退耕还林还草政策结合起来,统筹推进退耕还林还草工程,提升工程实施的质量。

森林资源培育工程对革命老区县域城乡收入差距的影响

【目的】在推进共同富裕的中国式现代化宏伟目标背景下,探究森林资源培育工程的实施对革命老区县域城乡收入差距的影响及其作用机制,为新时代新征程中推动革命老区及其他欠发达地区的共同富裕和中国式现代化道路提供支持参考。【方法】基于2008-2019年中国28省650个革命老区的县级面板数据,运用空间杜宾模型分析革命老区县森林资源培育对城乡收入差距的影响效应,并从收入效应和就业效应两个角度分析其影响机制。【结果】1)森林资源培育工程对革命老区本地区、相邻地区及整体地区的城乡收入差距均为扩大作用。具体而言,表征森林资源培育工程的造林面积每上升1%,会导致革命老区本地区、相邻地区及整体地区的城乡收入差距分别扩大0.035、0.200和0.236。2)森林资源培育工程主要是通过降低革命老区农村居民收入和提高城镇居民收入,从而扩大了整体城乡收入差距。3)机制分析结果表明,由于革命老区生态保护、人力资本、地理区位等方面的限制,森林资源培育工程的收入效应和就业效应释放不明显,使革命老区陷入“森林资源丰富而经济增长缓慢”的“森林资源诅咒”困境,从而增大其城乡收入差距。具体而言,森林资源培育工程对革命老区旅游收入没有影响,收入效应不显著;同时,森林资源培育工程的实施只能带动革命老区农民就业于劳动边际报酬较低的第一产业,而未能提高边际报酬较高的第二和第三产业就业,甚至挤出了第二和第三产业,就业效应不明显。【结论】应从森林保护和区域产业发展相结合、推动地区间联合进行森林资源培育、加强林业和其他产业的协调发展等方面发力,将革命老区森林资源的“绿水青山”优势有效地转变为“金山银山”的经济优势,利用丰富的森林资源降低革命老区城乡收入差距。

赣南地区森林生态保护与乡村振兴政策建议——以崇义县为例

森林为人类社会提供丰富的物质产品,在维持地球生命系统平衡方面发挥着无可替代的作用。本文聚焦赣南地区的森林生态保护与乡村振兴实践,以江西赣州市崇义县杰坝乡和赣南树木园为例,从探索高质量可持续发展的乡村旅游模式、打造人文生态资源依托型乡村和加快山水林田湖草沙系统治理与修复等三方面提出了发展方向,针对“双碳”背景下可持续利用森林资源促进乡村振兴重点提炼出4个可能的实现路径:(1)发展森林碳汇经济,提高森林碳储量和碳利用效率;(2)发掘特色农产品,搭建特色品牌产业链;(3)开发森林生态旅游,促进具有赣南特色的乡村振兴工作;(4)搭建政产学研用创新平台,努力推动经济社会整体协同发展。

兴安落叶松老龄林落叶松林木死亡格局以及倒木对更新的影响

对兴安落叶松老龄林落叶松林木死亡格局和死亡木对更新的影响进行了研究 .结果表明 ,丛桦落叶松林和杜香落叶松林的枯立木以中径木占多数 ,赤杨落叶松林主要为中、大径木 ,草类落叶松林主要是中、小径木 .落叶松枯立木主要因火烧、受压和老死而形成 .丛桦落叶松林和赤杨落叶松林掘根倒木较多 .杜香落叶松林和草类落叶松林的倒木以风折为主 .地形、山体走向和盛行风向对树倒方向影响很大 .丛桦落叶松林倒木方向杂乱 ,赤杨落叶松林林木均向东倒下 ,杜香落叶松林和草类落叶松林的掘根木分别向南、东北方倒下 ,两者的风折木倒向随机性较大 .草类落叶松和赤杨落叶松老龄林内 ,倒木更新为 1 8和 40株·m- 2 ,远远高于矿物土基质上 2株·m- 2 的水平 .丛桦落叶松林内倒木和林地上更新均相当好 ,约为 2 8株·m- 2 .杜香落叶松林倒木更新效果不突出 .

天然红松树木生长特征与林分结构的研究

通过对树木生长规律和群落结构、动态过程的研究,提出了应用树木生长模型研究林分垂直结构与树木生长动态之间相互关系的新方法。预测了红松树木生长和形态的时空模式以及树木不同发育阶段影响生长主要因子的差异性。结果表明,天然红松生长和形态特征的形成是与其林隙更新途径密切相关的。在树龄160a以前主要为高生长时期,受林隙形成的垂直层次上的生境控制;树龄在160a以后为径生长时期,林木达到上层林冠,从营养生长转变为生殖生长,顶端开始结实,主干开始分叉,叶面积增大,形态呈平顶状。此阶段林木生长主要依赖于立地条件。

长白山森林景观破碎的遥感探测(英文)

天然林数量的减少以及质量的降低对中国的生态环境和经济发展产生不利影响。虽然林地的破碎对各种自然灾害起到关键性作用 ,林地是如何被破碎的尚不十分清楚。应用卫星遥感技术 ,以及地理信息系统和空间分析手段研究中国东北一原始的针阔混交林的破碎过程。结果表明 ,本来完整的原始森林 ,已经被一种“复叶”状小面积皆伐作业分割为零碎的斑块。采伐地的面积平均为 1 5 hm2 ,但随着采伐的继续 ,采伐地段连为一体 ,增大了采伐迹地的面积 ,从而保留的林地面积越来越小。采伐地点的选择没有考虑物种和环境的保护。林地破碎的特征是保留林地面积的缩小 ,中、小林地数量的增加 ,林地斑块形状的改变 ,以及林缘长度的增加。

不同植被类型植物物种多样性

为了评价大面积人工种植杜仲对当地植物多样性的影响,以河南省汝阳县不同植被类型为研究对象,通过群落学调查,运用重要值、Shannon-Wiener物种多样性指数(H)、Simpson物种多样性指数(D)和均匀度指数(JH')等指标,统计分析杜仲人工林、温带落叶阔叶林(以下简称次生林)和撂荒地3种不同植被类型的植物物种多样性,探讨杜仲种植对植物多样性的影响。调查发现,杜仲林样地中出现植物82种,隶属39科63属,草本层为最发达的一层;次生林样地中出现植物70种,隶属32科62属,乔木层为最发达层;撂荒地样地中出现植物84种,隶属35科69属,无乔木层。杜仲林物种丰富度和多度均不亚于次生林和撂荒地,且杜仲林草本层物种丰富度和植株总数均高于次生林。统计分析显示,杜仲林乔木层、灌木层和草本层多样性指数H和D值、均匀度指数JH'值与其它两种植被类型相比无显著性差异(P>0.05)。因此,种植杜仲过程中采用合理密度,适当管理,不仅能提供叶、花、果等资源,而且能够丰富草本植物的种类和数量,增加植物物种多样性。