长白山北坡不同土壤N2O和CH4排放的初步研究

用箱法技术原位测定了长白山北坡不同土壤（苔原土、生草森林土、棕色针叶林土和暗棕色森林土）６—８月间的Ｎ２Ｏ和ＣＨ４排放．结果表明,这些土壤既是Ｎ２Ｏ的源,又同时是ＣＨ４的汇．Ｎ２Ｏ通量变化于６．１７—１２．３３μｇ·ｍ－２·ｈ－３之间（平均９．３７μｇ·ｍ－２·ｈ－１）,ＣＨ４通量为－８５．６３—－７．５８μｇ·ｍ－２·ｈ－１（平均－４１．４５μｇ·ｍ－３·ｈ－１）,并观察到在Ｎ２Ｏ排放和ＣＨ４吸收之间有着相互消长关系．实验室培养实验表明,最大反硝化作用活性存在于土壤上层（０—６ｃｍ）;不同土壤的反硝化作用活性明显不同．山地暗棕色森林土的ＣＨ４吸收作用也主要发生在土壤的上层（０—１２ｃｍ）．     

长白山野生经济植物数据库建立与应用研究

通过资源调查,实地拍摄,全面收集长白山野生经济植物的相关资料,用现代信息发展的数据管理技术,研究设计软件,组织构建整个检索系统,为研究长白山植物提供了第一手材料,对合理开发利用长白山资源,保护生态环境和植物物种基因起到了重要作用。     

长白山森林景观边界动态变化研究

通过野外调查、遥感和地理信息系统相结合的方法来研究长白山森林景观边界的动态变化规律,并通过相关性分析,探讨了长白山森林景观破碎化过程和景观边界指数变化的关系。首先对遥感影像进行计算机分类,其次,构建了描述景观边界的指标体系,再次,从景观边界的长度、密度、对比度、形状和多样性5个方面,对长白山森林景观边界的动态在景观类型尺度和景观尺度上进行分析。结果表明,在20多年的时问内,苔原面积减少了3694．8hm^2,云冷杉林的面积减少了130482．03hm^2,阔叶红松林面积增加了41610．4hm^2,岳桦林面积增加了66978hm^2．由于森林砍伐和毁林造田以及其它人类活动(如旅游)的影响,长白山森林景观的破碎化程度趋于增加,景观边界形状趋于复杂景观破碎化过程和景观边界指数变化的相关性分析证实了可以用景观形状指数(LSI)、对比度加权边界密度(CWEI))、边界加权总长度(TEGT)、加权景观形状指数(LSI-WGT)的变化来指示森林景观的破碎化程度。景观边界形状指数的大小还可以用来反映人类活动对景观的影响程度。最后,针对目前长白山森林景观破碎化程度趋于增大的情况,建议采取积极措施,防止长白山森林景观的进一步破碎化,以便更好地保护天然林。     

大气增温对长白山林木直径生长的影响

为研究全球性增温对温带森林生态系统的影响,在长白山采集了１３个树各１５５３１９８２－１９９１的年轮样品,对照有关气象资料进行了整理分析。结果表明年轮宽度的变化与气温指的年际变化之间很难找出一一对应的关系,但与１９８２－１９８６年相比,１９８７－１９９１年年平均气温增加０．４８℃,年轮平均宽度增加６．１％,与海拔下降１７６ｍ相应增温１℃,则使相应的年轮宽度增加５０％,以此计算,年均温度增加１℃将使阔     

关于调整竹林生态系统食物链的研究

关于调整竹林生态系统食物链的研究李昌荣,屠六邦,吴继林（南京林业大学,２１００３７）（福建省永安市大湖林业站,３６６０１５）王进荣,黄文培（江苏省溧水县秋湖林场,２１１２００）（四川省长宁万岭楠竹研究所,６４４３０４）ＳｔｕｄｙｏｎＲｅｇｕｌａｔｉｎ...     

长白山北坡森林群落结构组成及其海拔变化

对长白山北坡海拔700～1900m的13个森林群落进行了群落组成、结构随海拔上升变化情况的研究。结果表明,随着海拔的升高,群落的建群种组成、层次结构等,都表现出由复杂多样逐渐向简单单一过渡的变化趋势,从700m至1700m,针叶树所占的比例随海拔的升高呈明显的增加趋势,阔叶树比例随之减少,到林线时针阔叶树种均急剧减少,沿海拔梯度存在明显的树种更替现象。从群落的平均胸径及胸高断面积和可知。最大值出现于900～1100m及1600m,这2个海拔段正是不同森林群落类型间的过渡区。除海拔1800m的岳桦林之外,其它群落径级结构都呈倒J形分布,即各径级树木中,更新幼苗、幼树在数量上占绝对优势,随着胸径的增大,立木株数逐渐减少,这种径级结构表明,长白山北坡各海拔群落更新良好,群落处于稳定的发展状态。     

长白山自然保护区面临的问题及发展途径

1 自然概况长白山保护区是1960年经吉林省人民委员会决定建立的,1980年1月加入联合国教科文组织“人与生物圈计划”的国际生物圈保护区网,1986年经国务院批准,成立国家级自然保护区。保护区总面积196465公顷,其中有林地面积168918.5公顷,占全区总面积的86％,活立木蓄积4400万立方米。地理位置处于北纬41°41′49″～42°25′18″,东经127°42′55″～128°16′48″,全区南北最大长度80公里,东西最大宽度42公里。长白山保护区是以著名的火山口湖——长白山     

长白山种子植物区系研究

长白山种子植物区系是东北植物区系的一部分,它具有东北植物区种子植物的大部分种属,共有种子植物约１０９科４９６属１２７４种,是中国东北最丰富的高山型植物区系。此区系属于温带性质．特有现象明显,垂直替代与水平替代现象也均表现明显,地理联系广泛,但以与东亚其它地区特别是与日本的联系最为密切,种类成分复杂,共有１７个分布型与１７个分布亚型,其中包含有少量热带性质成分和一些寒带性质成分,而主要的则是以占半数以上的温带性质的东亚地区成分为主体,渗入了相当数量的北温带地区成分和若干其它温带成分所组成的。起源时间不晚于第三纪。     

长白山森林生态系统服务功能

长白山森林生态系统是亚洲东部最典型的、保存最完好的温带山地森林生态系统, 对维持松花江、鸭绿江和图们江三大流域生态系统的结构和功能具有重要的作 用. 采用物质量和价值量相结合的评价方法, 对长白山北坡森林生态系统的生态旅游、森林林副产品、木材、涵养水源、水土保持、净化空气、营养元素循环等服务价值及其总体服务价值进行了评估及动态分析. 结果表明, 1999年服务功能价值达3.38 ´ 10⁸万元. 涵养水源服务价值是长白山森林生态系统服务价值的主要部分, 占66%, 涵养水源和净化空气作为森林生态系统最重要的生态功能, 其服务价值占总服务价值的80%, 而木材生产的服务价值仅占总价值的7%. 由此可见, 木材生产并不是森林生态系统服务价值中的主要部分, 充分发展长白山森林生态系统其他的生态功能, 才是发挥其生态系统服务价值的最佳途径.     

花背蟾蜍摄食生态的研究

花背蟾蜍摄食生态的研究周立志宋榆钧（东北师范大学生命科学学院,长春１３００２４）ＡＳｔｕｄｙｏｆＦｅｄｉｎｇＥｃｏｌｏｇｙｏｆＢｕｆｏｒａｄｄｅｉ．ＺｈｏｕＬｉｚｈｉ,ＳｏｎｇＹｕｊｕｎ（ＣｏｌｅｇｅｏｆＬｉｆｅＳｃｉｅｎｃｅ,ＮｏｒｔｈｅａｓｔＮｏ...     

中国森林健康生态风险评价

我国森林每年都在遭受诸如过度砍伐、火灾、病虫鼠害、酸雨、气象灾害等各种形式的干扰．这些干扰对我国森林生态系统的健康状况造成很大的威胁．因此,如何有效地管理我国的森林资源,特别是对森林的生态风险管理,提高森林生态系统抵御风险的能力,是森林生态系统健康研究和森林可持续管理的首要任务之一．森林健康生态风险评价是描述和评价人为活动、自然灾害和环境污染等胁迫因子对森林生态系统结构和功能、森林生态系统的健康状况产生不利影响的可能性和危害程度的评估,是森林资源管理的一个重要环节．以我国森林生态系统为例,探讨森林健康生态风险评价的研究方法,并以森林火灾、病虫害和酸雨为生态风险源,运用生态风险评价方法,分析了这些风险源对森林健康的主要危害,对我国森林健康的风险进行了综合评价,并提出不同森林风险区的管理策略．     

The Value of Opinion in Science and the Forest Service Research Organization

ABSTRACT There is confusion about conflicts of interest between sources of funding and the extent to which Forest Service researchers are free to publish their findings. Forest Service Research is an independent entity with no administrative accountability to policy makers up to the office of the Chief of the Forest Service. Congressional mandate ensures that research will be free from the influence of politics that land management necessarily entails. Because politics involves opinions, it is important to note that opinions per se are not scientific and must be appropriately compared with empirical data before they can be considered so. It is the quantitative test of an opinion that renders it scientific, not the opinion itself.     

Age-related Decline in Forest Ecosystem Growth: An Individual-Tree, Stand-Structure Hypothesis

Forest growth is important both economically (yielding billions of dollars of annual revenues) and ecologically (with respect to ecosystem health and global carbon budgets). The growth of all forests follows a predictable general trend with age. In young forests, it accelerates as canopies develop; it then declines substantially soon after full canopy leaf area is reached. The classic explanation for the decline in growth invoked the increasing respiration costs required to sustain the larger masses of wood characteristic of older forests. Direct measurements of respiration have largely refuted this hypothesis, and recent work has focused on stand-level rates of resource supply, resource use, and growth. We developed and tested a hypothesis at the scale of individual trees (in relation to stand structure) to explain this declining stand-level rate of stem growth. According to our hypothesis, changes in stand structure allow dominant trees to sustain high rates of growth by increasing their acquisition of resources and using these resources efficiently (defined as stem growth per unit of resource used); smaller, nondominant trees grow more slowly as a result of their more limited acquisition of resources and a reduced rate of growth per unit of resource acquired. In combination, these two trends reduce overall stand growth. We tested this hypothesis by comparing growth, growth per unit of leaf area, and variation among trees within plots in two series of plantations of Eucalyptus in Brazil and by estimating individual-tree rates of growth and use of light, water, and nutrients in a plantation of Eucalyptus saligna in Hawaii. Our results supported the individual-tree hypothesis. We conclude that part of the universal age-related decline in forest growth derives from competition-related changes in stand structure and the resource-use efficiencies of individual trees. Received 19 February 2001; accepted 19 June 2001.     

嫩江上游流域生态系统水量平衡的研究

以2级流域为研究单元,在流域结构特征调查分析的基础上,通过不同生态系统和不同森林类型对降水再分配的观测,从林分、生态系统和流域不同尺度和水平上定量分析了森林类型、生态系统、流域的水量平衡。结果表明,落叶松人工林的林冠截留率最大,表现出比天然白桦林、天然黑桦和天然阔叶混交林具有较强的蓄水和拦截功能,蒸散是森林生态系统水分输出的主要形式,天然阔叶混交林和人工针对林径流量相对较小,蒸散也是农田和草地水分输出的主要形式,它们的蒸散值分别占降雨量的91．06％、81．02％,草地蒸散值大于森林,具有较小的径流,表现出很强的蓄水保水作用,而农田蒸散值小于森林,径流量最大,总裁总蒸散占降水的80．84％,径流占23．26％。     

Forest Management Policy, Amenity Migration, and Community Well-Being in the American West: Reflections from the Northwest Forest Plan

This paper examines the relation between public land management policy, amenity migration, and socioeconomic well-being using the case of the Northwest Forest Plan—a forest management policy that caused 11.6 million acres of federal land in the US Pacific Northwest to be reallocated from commodity production to biodiversity services. Our analysis focuses on three propositions implicit in much of the amenity migration literature in the USA: land management policies that reduce commodity production and/or increase environmental protection (1) improve the natural amenity values of public lands; (2) increase amenity migration to communities near public lands; and (3) stimulate economic development and increase socioeconomic well-being in these communities. Our findings indicate that all three propositions are problematic and demonstrate the importance of community-scale analysis for understanding the relation between land management policies, amenity migration, and community well-being. We discuss the implications of our findings for public land management and rural community development.

Ecosystem Management of Desertified Shrublands in Israel

The objectives of this study were to understand the ecological processes and possible management strategies in desertified shrublands. We hypothesized that biological production and diversity in desertified shrublands in the Negev in Israel are low due to water, soil, and nutrient leakage from the ecosystem. We designed a series of field experiments in order to examine (a) whether source–sink relationships exist between the crusted soil and the shrub patches, (b) whether resources (water, soil, and nutrients) leak from the system, and (c) whether management, which changes the landscape mosaic by introducing new sink patches that reduce leakage of resources, may increase productivity and diversity. The results indicate that the low number of shrub patches, which serve as sinks for resources, leads to water, soil, and nutrient leakage from the ecosystem. This leakage reduces ecosystem production and diversity. We found that artificially created pits, which act as sinks for resources, decrease leakage and increase biomass production and annual plant species diversity. Based on the experimental results, we developed conceptual models for shrubland desertification and ecosystem management. The models are based on a source–sink relationship between two patch types characteristic of shrublands. The models relate landscape productivity to the number of sink patches and suggest that, in cases where there are too few sinks, artificially created sink patches should be added. Management methods were developed to reduce resource leakage in the desertified shrubland of the Negev. Methods included construction of man-made pits in the landscape that add resource-enriched patches to the landscape. These patches are used to create parks consisting of clusters of trees integrated into a matrix of shrubs and herbaceous vegetation. The managed parks are used for recreational purposes and for rangeland. Received 8 July 1997; accepted 7 July 1998.     

松林复合经营模式的试验与评价

复合经营系统就是在某一特定的自然环境区域中,根据不同的生物学特性,组成空间的多层次结构、时间的有序配置,以充分利用光热资源、空间资源和土地资源。以物质和能量的多级利用,有效地提高生态、经济和社会效益［１～３］。通过对复合经营系统的实践和研究,积累和总...     

西双版纳勐宋哈尼族的传统文化与生态系统多样性管理

世界各地的原住民族 (ｉｎｄｉｇｅｎｏｕｓｐｅｏｐｌｅ) ,在悠久的历史发展过程中 ,与当地的动植物和森林结成了极其密切的关系 ,他们之间互相作用、互相影响 ,形成了多样化的原住民知识体系 (ｉｎｄｉｇｅ ｎｏｕｓｋｎｏｗｌｅｄｇｅｓｙｓｔｅｍ)和传统文化信仰 (ｃｕｌｔｕｒａｌｂｅｌｉｅｆｓ)。这些知识体系和传统文化包含着丰富的认识、利用与保护动植物以及生态系统的知识与实践 ,因而也就成为这些原住民族与当地生态环境、生物多样性相互协调和持续发展的社会基础和技术保障[3 ,8,1 0 ,1 1 ] 。在全球性环境变化和生物多样性迅…