黑河(中游)湿地维管束植物多样性评价研究

位于干旱半干旱区的黑河湿地资源弥足珍贵,针对湿地生物多样性亟待保护的现实,基于物种多样性、遗传多样性和生态系统多样性三个层次水平,提出了分布区类型、特有种、保护物种、物种多度、物种丰富度、物种均匀度、湿地面积、湿地类型、保护地类型、人类威胁十项评价指标,初步建立了一套评价黑河湿地维管束植物多样性的指标体系、方法和标准,为湿地维管束植物的科学保护、合理利用和有效管理提供依据。     

云南泸沽湖省级自然保护区生物资源现状及评价

据1982年3月、2003年8月、2008年6月对云南泸沽湖省级自然保护区的3次动植物资源调查统计,保护区有维管束植物137科440属870种,其中蕨类植物有17科27属41种,种子植物有120科413属829种。植被有8个植被型,11个植被亚型,31个群系。原生脊椎动物104种,其中哺乳类29种,鸟类65种,两栖爬行类6种,鱼类4种。阐述了保护区具有生态系统完整、典型、自然、脆弱、生物多样性丰富,物种珍稀特有,起源古老、孑遗等基本特征。提出了保护生物多样性的建议。     

山东禹王湿地公园植物多样性分析

对山东禹王湿地公园的植物多样性进行了研究,结果表明:公园内有维管束植物56科111属185种,裸子植物5科9属16种,被子植物51科102属169种;该区的植物多样性表现为区系成分复杂,起源古老,特有种和珍稀濒危种多,资源植物丰富;禹王湿地公园规划拟通过湿地生境系统的保护、改造与利用,营造多样性的生物景观序列,从而构建丰富的景观类型与内容。     

安徽牯牛降北坡种子植物区系特征及其多样性的海拔梯度变化

【目的】分析安徽省牯牛降国家级自然保护区北坡种子植物区以及植物多样性,为该区植物资源保护和利用提供依据。【方法】对牯牛降北坡植被垂直带进行样地调查并划分植物区系,分析不同海拔梯度植物群落的物种多样性。【结果】保护区种子植物丰富,区系起源古老,地理成分复杂;共有种子植物145科687属1 414种(含种下分类单位);科属的优势现象明显,属的组成相对较为分散,寡种属和单种属占总属数的94.32%;植物分布区类型表现出从亚热带到温带过渡的区系特点;牯牛降北坡植被垂直带谱为海拔800 m以下为常绿阔叶林,800~1 100 m为常绿落叶阔叶混交林,1 100~1 300 m为落叶阔叶林,300~1 500 m为针阔叶混交林,海拔1 500 m以上为黄山松针叶林;随海拔升高,植被类型表现为从亚热带常绿阔叶林向暖温带落叶阔叶林过渡;物种丰富度和多样性指数大致表现出沿海拔升高而降低的趋势;受冰川影响,南坡海拔高差大,地势陡峭,土壤层薄,因而在相同海拔条件下,北坡的物种丰富度往往大于南坡。【结论】该保护区北坡具有很高的物种多样性保护价值,物种多样性随海拔升高而下降,最大的物种多样性出现在中海拔地带。对牯牛降保护区北坡进行植被监测时,应以大样地为主要监测方法,以海拔700~1 000 m的落叶阔叶林作为主要监测对象。对北坡科普、旅游区域需进行全面系统的环境承载力和环境影响评估,建立完善生态旅游规划体系,并依照自然景观进行合理布局。     

景宁望东垟、大仰湖自然保护区种子植物区系分析

2013-2015年,对景宁县望东垟高山湿地自然保护区和大仰湖湿地群自然保护区进行了植物资源调查,结合历史资料统计分析了两个保护区种子植物区系。结果表明,两个保护区共有种子植物153科725属1 692种,其中野生种子植物141科644属1 529种。从科级水平看,以寡种科最多,共70科,占总科数的49.6%,其次是单种科29科,占20.6%,大种科最少,仅6个,占总科数的4.3%。从属级水平看,寡种属、单种属极为丰富,分别有243属和353属,占总属数的37.70%和54.8%。科的分布区类型,热带性地理成分63科(不含广布),占总科数的67.0%,温带成分31科,占总科数的33%,说明科的地理成分具有较强的热带性质。属的分布区类型,热带分布类型256属,占总属数(不包括世界分布属)的43.6%,温带分布类型319属,占总属数的54.3%,说明具有温带和亚热带性质。调查显示两个保护区植物多样性丰富,区系起源古老,孑遗植物多,特有属种多,区系成分复杂多样,具有较明显的过渡现象。     

菌子山自然保护区植物多样性特征

菌子山自然保护区位于曲靖市师宗县境内，珠江上游南盘江两岸。气候属北亚热带气候类型，热量充足、温差大、降水充沛、霜日少。森林植被茂密，种类丰富，共分布维管束植物991种，分属于184科637属。保护区物种丰富，区系地理成分复杂，起源古老、孑遗、珍稀种类兼备，岩溶植被发育完整，具有植物生活型多样，植被类型多样等特征。由于近几十年森林植被的不合理利用，植物多样性遭到破坏，应采取措施加以保护。     

四川毛寨自然保护区种子植物区系特征

通过对四川毛寨自然保护区内种子植物的调查及其科、属的分布区类型统计,得出区内种子植物具有如下区系特征:①区系成分较为复杂,种类丰富;②优势科明显,种子植物起源古老;③保护区内种子植物区系具温带性质;④植物区系过渡性明显;⑤中国特有种丰富;⑥珍稀濒危和保护植物丰富.     

九龙山自然保护区国家重点保护野生植物及基本特征

调查统计表明,九龙山自然保护区国家保护植物有21 种,隶属于13科19属.可以分为10 个分布区类型,以木本植物占优势,区系起源古老,孑遗植物众多,特有现象显著.根据九龙山国家重点保护植物的现状提出了一些具体的保护措施.     

长江口北支湿地植物多样性研究

在对长江口北支湿地植物资源野外调查的基础上,分析了种子植物的物种组成、区系特征、湿地植物群落类型及其特征和典型湿地植物群落多样性。研究结果表明：长江口北支湿地分布有种子植物57科157属212种,其中裸子植物5科6属6种,被子植物52科151属206种（包括单子叶植物8科31属37种,双子叶植物44科120属169种）,主要由草本植物组成。野生植物区系简单,植被演替还处在初级阶段,以湿生的和水生高等草本植物为主,世界广布和泛热带分布型占主导;菊科、禾本科、豆科为植物区系的骨干。海三棱蔗草群落、藤草群落、芦苇群落、大米草群落为该区四种典型湿地植物群落,群落的单纯度指数除芦苇群落的较低外,其他三种群落均很高,物种多样性指数、物种丰富度指数、均匀度指数除芦苇群落的较高外,其他三种群落均很低,验证了物种多样性与物种丰富度、均匀度呈正相关,与单纯度呈负相关的结论。     

浦城福罗山植物多样性调查分析与评价

调查表明,浦城福罗山野生维管束植物有200科710属1 435种;区系地理成分复杂,种子植物属的分布区类型有14个,热带成分(330个属,占56.99%)多于温带成分(249个属,占43.01%)各级珍稀保护植物共计15科48种植被类型多样,天然植被有11个植被型,以森林为主。基于植物多样性现状评价,体现该区地理和生态的重要性、生态系统的完整性与典型性、物种和生态系统的多样性、物种的稀有性、生态系统的脆弱性。     

Browsing Damage on Pine (Pinus sylvestris and P. contorta) by a migrating moose (Alces alces) Population in Winter: Relation to Habitat Composition and Road Barriers

In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads.     

Effects of Root Freezing on the Physiology and Growth of Picea glauca,Picea mariana and Pinus banksiana Seedlings Under Different Soil Moisture Regimes

The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage.     

Stand Structure in Pine,Spruce and Deciduous Forests: A Comparison Between Finnish and Russian Karelia

This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland.     

Growth and Terminal Bud Formation in Picea abies Seedlings Grown with Alternating Diurnal Temperature and Different Light Qualities

The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions.     

CAD与建筑设计的关系

本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。     

Natural Regeneration in Clear-cuts: Effects of Scarification,Slash Removal and Clear-cut Age

The effects of soil scarification (mounding), slash removal and clear-cut age on the natural regeneration in clear-cuts was evaluated using data from four sites in southern Sweden. The treatments were carried out during a good seed and establishment year for birch ( Betula pubescens Ehrh. and B. pendula Roth). Scarification had the strongest positive effect on the density of naturally regenerated seedlings, especially in birch, but also in pine ( Pinus sylvestris L.) and spruce [ Picea abies (L.) Karst]. Slash removal had a positive effect on birch density. No statistically significant effect of clear-cut age was found. In addition, no statistically significant interactions between clear-cut age and scarification or slash removal were found. The ingrowth of field vegetation was the fastest in areas that were not scarified, less rapid in areas scarified on old clear-cuts, and the slowest after scarification in fresh clear-cuts. In conclusion, it may be possible to control the density of birch during a good establishment year for birch. If birch is desired, the best combination of treatments is to remove the slash and scarify; otherwise, these treatments should be avoided.     

Risk Perception Among Non-industrial Private Forest Owners

Based on an enquiry, risk perception among non-industrial private forest owners is described in relation to climate change and forestry hazards. Of the respondents, 11% took action to remedy the effects of climate change. Out of a given set, hazards were ranked according to each respondent's experience of recent substantial financial loss to the estate and in relation to his or her willingness to make investments aimed at risk reduction. For each hazard, the respondent assessed the risk in four classes ranging from very high to negligible risk. Six hazards were considered most problematic in all three aspects: browsing damage, falling timber prices, damage by wind, spruce bark beetle, root rot and pine weevil. A majority of the respondents claimed to take action to reduce the risk associated with at least one hazard, while 35% did not know whether they did. Excluding climate change, the need for decision support was the largest in relation to damage by wind owing to a combination of perceived high risk and a high level of ignorance in relation to whether risk-reducing measures were taken.     

Interactions in decomposition and N mineralization between tropical legume residue components

In situ produced plant residues contain a mixture of different plant components of varying quality. To assess synergistic or antagonistic interactions occurring during the decomposition and mineralization of such mixtures, individual plant parts (stems, leaves, leaf litter and roots) or the mixture of stems, leaves and leaf litter of the agroforestry species pigeonpea (Cajanus cajan) or of crop residues of peanut (Arachis hypogaea) or of the weed hairy indigo (Indigofera hirsuta) were incubated in pots for 19 weeks. Periodically, remaining plant residues were sieved out (>2 mm), weighed and N content as well as soil mineral N determined. Above- and below-ground residues of peanut decomposed fastest and showed the largest N release in agreement with their high N concentration and low-acid detergent fibre (ADF) : N ratio. Hairy indigo was hypothesized to be of lower quality than pigeonpea because of its high-polyphenol content. However, it decomposed faster than pigeonpea, largely because of the higher N and lower lignin concentration of its components. Ranking of individual plant components for N mineralization resulted in the following pattern, leaves > leaf litter > roots > stems. In mixtures of the different plant components a similar species order in decomposition was obtained, e.g. peanut > hairy indigo > pigeonpea. The amount of N released from the mixture was dominated by stem material that comprised 46–61% of the mixture. The interactions in mixtures were relatively small for peanut (generally high-quality components) as well as for pigeonpea (low proportion of high-quality components, i.e. N rich leaf material). However, a positive interaction occurred during later stages of N mineralization in the mixture of hairy indigo as it had a significant proportion of N rich components and absence of highly reactive polyphenols. Thus, for plants with low to intermediate chemical quality attributes, manipulating plant composition (e.g. by varying harvest age, affecting stem and leaf proportions) will be important to obtain significant interactions during decomposition when its components are mixed.     

Pasture production and tree growth in a young pine plantation fertilized with inorganic fertilizers and milk sewage in northwestern Spain

The use of organic waste materials such as milk sewage as an organic fertilizer could have the dual advantages of organic-waste disposal and reduced dependence on inorganic fertilizers. The effects of fertilization with (1) conventional mineral fertilization, (2) milk sewage sludge at 40 kg N ha⁻¹ target rate and (3) no fertilization on pasture production and tree growth were examined in an experiment consisting of two pasture mixtures under a one-year-old Pinus radiata plantation with a density of 2500 trees ha⁻¹. The two pasture mixtures were: (1) Dactylis glomerata L. var. saborto (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹); (2) Lolium perenne L. var. Tove (25 kg ha⁻¹) + Trifolium repens L. group Ladino (4 kg ha⁻¹) + Trifolium pratense L. var. Marino (1 kg ha⁻¹). The experiment began in the spring of 1995 using a randomized block design with three replicates in Castro Riberas de Lea (Lugo, Galicia, north-western Spain). Plot size was 12 × 8 m², with a 1 m buffer strip between plots. Two-year data showed that fertilization with either material had a positive effect on pasture production, with no significant difference between the two fertilization treatments. Tree growth in the milk sewage sludge plot was significantly higher than in the control plots. Inorganic fertilization increased pasture production, but affected tree growth negatively. The results show that milk sewage sludge could be used as a fertilizer in silvo-pastoral systems. This revised version was published online in June 2006 with corrections to the Cover Date.