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1.
The relationship between the change of forest resources and climatic factor in the, “Three-North” region of China were studied
in this paper. The predicting equations of climatic factor (dependent variable) with regional independent variable (longitude,
latitude and altitude) and stand independent variable (forest coverage rate), were developed by extensively using the linear
and nonlinear regression methods. With these models, we can calculate the ecological benefit of Shelter-belt forest.
Responsible Editor: Chai Ruihai 相似文献
2.
本文旨在对内蒙古西部乌兰布和沙区周边绿洲农区防护林体系的气候生态效益进行评价,并分析三北防护林工程建设之前,三北防护林工程一期工程和二期工程3个时期的变化趋势,建立防护林体系变化与气候变化的关系模型。研究结果表明：（1）防护林体系的变化对气候因子风速,大风日数,扬沙日数,沙尘暴日数有一定的影响,体现了防护林体系的生态屏蔽作用;（2）防护林体系的变化对年平均温度,湿度,降水量,持续干旱日数和霜期等因子影响不明显,这是因为这些因子的变化主要受大气环流控制所致。 相似文献
3.
Shouzhang Peng Chuanyan Zhao Yunming Chen Zhonglin Xu 《Scandinavian Journal of Forest Research》2017,32(2):166-173
The current work adopted the Biome-BioGeochemical Cycle model to simulate the net primary productivity (NPP) of a subalpine forest (Picea crassifolia forest) under four representative concentration pathway (RCP) scenarios in the Qilian Mountains of northwest China. This study also investigated the responses of forest’s NPP to different combinations of climatic changes and CO2 concentration increase. Results showed that (1) under the RCP scenarios, greater increases in temperature, precipitation, and CO2 concentration caused larger increments in forest NPP; (2) the effect of CO2 concentration (increased NPP from 19.9% to 21.7%) was more significant than that of climate change (increased NPP from 7.5% to 17.1%); (3) the simultaneous increments in climatic change and atmospheric CO2 concentration led to a remarkable increase in P. crassifolia forest NPP (ranging from 33.1% to 41.3%), with the combination of the two exerting strong interactive effects on forest NPP; and (4) the response of the forest’s NPP to future global change was more intense at high elevations than at low ones, with the temperature being the main factor controlling forest NPP variation at the high-elevation regions. These valuable predictions can help clarify how subalpine forest ecosystems respond to simultaneous or independent changes in climate and CO2 concentration. 相似文献
4.
中国森林生态效益计量研究 总被引：10，自引：0，他引：10
通过对森林多种生态效益的分析,确定计量森林生态效益的因变量指标集为:涵养水源效益、保持水土效益、抑制风沙效益、改善小气候效益、吸收二氧化碳效益、净化大气效益、减轻水旱灾效益、游憩资源效益和野生生物保护效益。同时,从影响因变量的众多因素中筛选出主要变量建立自变量集,并将之划分为区域自变量(经度、纬度、海拔、年降雨量、年平均风速和年≥10 ℃积温)和林分自变量(森林蓄积量和森林覆被率)。按照以上建立的计量指标体系,建立了森林生态效益计量的多元线性模型。利用该多元线性模型对我国森林的生态效益进行了计量,得到我国森林每年产生的生态效益为7 238.16亿元,占国内生产总值的23.07%。 相似文献
5.
[目的]确定退化森林生态系统中林分碳储量的驱动因素,为其碳汇功能的恢复提供参考。[方法]基于调查数据,使用逐步回归的方差分析法和结构方程模型(SEM)法,考虑林分因子和非生物环境因子(地形、气候),探究林分碳储量的驱动因素。[结果]2种方法得到的结果基本一致:方差分析法的确定系数为0.890,林分因子中的平均胸径和株数密度,非生物环境中的月平均最高温和月平均最低温以及干扰类型对林分碳储量有显著影响;SEM中林分碳储量部分的模型确定系数为0.757,林分因子中的平均胸径和株数密度对林分碳储量的影响最大,其中株数密度既有正向的直接作用,也有负向的间接作用,而非生物环境中,月平均最高温对林分碳储量有间接的负向影响,各变量对林分碳储量的影响大小排序为平均胸径(0.94)>月平均最高温(-0.52)>株数密度(0.12)。[结论]综合2种方法得到的结果,在退化森林生态系统中,林分因子和气候因子均对林分碳储量有影响,而地形因子却对其无显著影响。研究结果可为大兴安岭森林碳库探究提供数据参考和借鉴。 相似文献
6.
Our goal was to predict the spatial distribution of canopy species composition in secondary deciduous hardwood forests at
a fine spatial resolution, based on climatic and topographical factors using a geographic information system. We studied secondary
forests on Mt. Gozu, Niigata Prefecture, central Japan. Canopy species composition was investigated in 100 sample plots within
the study area. A digital elevation model (DEM) was created, and topographical, hydrological, and light factors were calculated
using the DEM. Climatic factors were interpolated by kriging. The five major species used as response variables were Fagus crenata, Quercus serrata, Quercus crispula, Magnolia obovata, and Castanea crenata. We prepared three possible explanatory variable sets: climatic variables only, both climatic and topographic variables,
and topographic variables only. Multivariate regression trees were derived, and the accuracy of predicting the major species
composition was tested. The multivariate regression trees derived from the climatic variable set and from the climatic and
topographic variable set had better accuracy than the regression tree derived from the topographic variable set. In the regression
tree generated by the climatic and topographic variable set, the warmth index was the principal explanatory variable in classifying
forest types, followed by topographic factors. This regression tree would be preferable to the other two regression trees
for the prediction of canopy species composition. 相似文献
7.
从德国“可持续”森林利用的不同概念、德国不同森林认证体系“经营标准(Management Standards)”的比较实例、德国森林经营和“近自然森林经营”筒史、德国森林资源状况和森林资源的变化、德国有关森林资源的几个基本理念与“近自然森林经营”的主要特征、德国哥廷根市有林“近自然森林经营”实例等6个方面,简要介绍了德国的“近自然森林经营”。 相似文献
8.
Kotaro Zushi 《Journal of Forest Research》2007,12(4):289-297
Digital terrain modeling and spatial climatic data have been used to estimate the spatial distribution of Japanese cedar (Cryptomeria japonica D. Don) forest productivity on a regional-scale. The study was conducted on Japanese cedar forests in Himi city, Oyabe city,
Takaoka city, and Imizu city (a total area of 683 km2) in northwestern Toyama Prefecture. On the basis of data from 146 sample stands, above-ground net primary productivity (ANPP)
was calculated from tree height, age, and density using existing ANPP conversion equations for Japanese cedar stands. Six
topographic factors (slope, profile curvature, plan curvature, openness, wetness index, and topographic radiation index) were
calculated from a 10-m cell size digital elevation model. Three climatic factors (annual mean temperature, annual total precipitation,
and annual maximum snow depth) were obtained from an existing spatial data set. Relationships between ANPP and environmental
factors were analyzed by regression tree models. For the tree model with ANPP as a dependent variable, four environmental
factors (annual mean temperature, wetness index, openness, topographic radiation index) were adopted as independent variables.
Annual mean temperature was the first split variable in this model and explained 25.5% of the total deviance in ANPP. Wetness
index, which represents soil moisture variation caused by lateral flow, explained 11.5% of the total deviance in ANPP. The
resulting tree model explained approximately half of the total deviation in ANPP and indicated that the spatial distribution
of Japanese cedar productivity was controlled by regional-scale interactions between climatic and topographic processes. A
high-resolution map of productivity was prepared by use of the ANPP prediction model and vegetation information obtained from
satellite data. 相似文献
9.
通过林木引种灰色关联度分析 ,探讨永安市引种的巨桉、巨尾桉在相同立地条件下其生长与气候因子的关系。结果表明降水量是影响巨桉、巨尾桉生长的主导气候因子。 相似文献
10.
Adel Mohamed Robin M. Reich Raj Khosla C. Aguirre-Bravo Martin Mendoza Briseño 《林业研究》2014,25(1):87-95
This paper presents an approach based on field data to model the spatial distribution of the site productivity index （SPI） of the diverse forest types in Jalisco, Mexico and the response in SPI to site and cli-matic conditions. A linear regression model was constructed to test the hypothesis that site and climate variables can be used to predict the SPI of the major forest types in Jalisco. SPI varied significantly with topog-raphy （elevation, aspect and slope）, soil attributes （pH, sand and silt）, climate （temperature and precipitation zones） and forest type. The most important variable in the model was forest type, which accounted for 35% of the variability in SPI. Temperature and precipitation accounted for 8 to 9% of the variability in SPI while the soil attributes accounted for less than 4% of the variability observed in SPI. No significant differences were detected between the observed and predicted SPI for the individual forest types. The linear regression model was used to develop maps of the spatial variability in predicted SPI for the individual forest types in the state. The spatial site productivity models developed in this study provides a basis for understanding the complex relationship that exists between forest productivity and site and climatic conditions in the state. Findings of this study will assist resource managers in making cost-effective decisions about the management of individual forest types in the state of Jalisco, Mexico. 相似文献
11.
杨树是我国低山丘陵半干旱区河滩地重要的防护用材林树种之一,探讨其生长量与气候因子的定量关系,可为该地区河滩地杨树防护用材林集约栽培及其低产林的更新改造提供科学依据。本文以该地区大、小凌河两岸河滩地为典型试验区,经多年连续观测,通过林木调查和树干解析,应用多元逐步回归和灰色系统理论与方法,建立了杨树生态防护用材林高生长量与气候环境因子的回归模型,气候环境因子对其生长量影响程度的灰色关联顺序为光>水>气>热,即可认为影响杨树高生长的主导因子是光照因子,其次是水分因子,再次是热量因子。表2参17。 相似文献
12.
13.
“一带一路”沿线区域森林草原防火概述 总被引：1，自引：1，他引：0
森林草原火灾是目前世界上最为严重的自然灾害和突发公共事件之一。在全球气候变化下重大森林草原火灾已成为制约“一带一路”沿线区域森林草原资源可持续发展的限制因素之一。如何快速有效地防止和控制森林草原火灾,减少其造成的损失是“一带一路”沿线区域乃至世界各国政府共同关注的问题。文中分析了“一带一路”沿线区域森林草原的基本特征,研究了沿线区域森林草原火灾发生的基本特征和防控对策,提出了“一带一路”背景下我国森林草原防火国际化合作的对策与建议,其研究结果对于加强“一带一路”沿线区域森林草原防火国际合作以及提高我国森林草原防火水平具有一定的参考意义。 相似文献
14.
Based on the data of stand investigation and stem analysis, the effects of climate factors on the poplar protection forest
increment in the riverbank field of the Dalinghe and Xiaolinghe rivers of Liaoning Province, China were studied by stepwise
regression procedure and grey system theories and methods. A regression model reflecting the correlation between the height
increment of poplar protection forest and climatic factor was developed. The order of grey relevance for the effect of climatic
factors on the height increment of poplar protection forest is: light>water>heat, and it could be interpreted that the poplar
increment was mainly influenced by light factor, water factor, and heat factor. This result will provide scientific basis
for the intensive cultivation and regenration of the poplar protection forest in riverbank field in similar regions in China.
Foundation item: This study was supported by the National Natural Science Foundation of China (No. 30270250), and a key direction project
(No. C12MC-SCMS013)
Biography: LI Hai-mei (1975-), female, Ph. D, department of Landscpe Architecture. Art. Laiyang Agricultural College, Shandong Qingdao
266109, P. R. China.
Responsible editor: Song Funan 相似文献
15.
广西红锥天然林原生境自然因子调查分析 总被引：1，自引：1，他引：1
通过调查统计广西15个红锥(Castanopsis hystrix)天然林县市的气候和土壤因子,结果表明广西红锥天然林分布的地区属南亚热带季风气候区,以红锥天然林为主的森林是我国南亚热带季雨林化常绿阔叶林的代表类型;红锥天然林分布以赤红壤、红壤林地出现较多,土壤酸碱度为微酸性(pH 4.36~6.23)。根据对广西红锥天然林原生境生长发育的主要气象因子的分析结果,初步确定广西红锥的现实生态位宽度。 相似文献
16.
Possible Impacts of Climatic Warming on Trees and Forests in the United Kingdom: a Review 总被引：2，自引：0，他引：2
There is growing evidence and concern that increasing levelsof greenhouse gases in the atmosphere will increase global temperatures.Temperatures in the UK may increase by 3C± 1.5C overthe next 70 years The tree crop is sensitive to such large andrapid climatic change because of its longevity. This paper reviews(1) changes that might occur in the forest environment, includingsoil, following climatic warming; (2) past and future long-termchanges in the species composition of UK forest; (3) possiblepositive and negative effects.of climatic warming on the growthand yield of UK forests; and (4) the vulnerability of foreststo any change in the frequency of extreme events. 相似文献
17.
Jesús Julio Camarero Christof BiglerJuan Carlos Linares Eustaquio Gil-Pelegrín 《Forest Ecology and Management》2011,262(5):759-769
The causal factors and effects of forest declines are not well understood in temperate conifer forests. Most studies have focused on climatic and environmental stressors and have obviated the potential role of historical forest management as a predisposing factor of decline. Here, we assess if the recent silver fir (Abies alba) decline observed in the Spanish Pyrenees was predisposed by historical logging and incited by warming-induced drought stress. We analysed a dataset of environmental, structural, and historical variables at the tree and stand level including 32 sites with contrasting degrees of defoliation distributed over 5600 km2. We followed a dendroecological approach to reconstruct historical logging and to infer the effects of warming-induced drought stress on growth. The silver fir decline was more severe and widespread in western low-elevation mixed forests dominated by trees of small size and slow growth. These sites were subject to higher water deficits than eastern sites, where late-summer rainfall as the key climatic variable controlling silver fir growth was higher. Declining sites showed more frequent growth releases induced by historical logging than non-declining sites. Historical logging and warming-induced drought acted as long-term predisposing and short-term inciting factors of silver fir decline in the Pyrenees, respectively. We suggest that biomass increases caused by past intense logging affected the vulnerability of silver fir against late-summer water deficit. Future research in declining temperate conifer forests should consider the interacting role of predisposing historical management and inducing climatic stressors such as droughts. 相似文献
18.
Quantitative information of tree biomass is useful for management planning and monitoring of the changes in carbon stock in both forest and agroforestry systems. An estimate of carbon stored in these systems can be useful for developing climate change mitigation strategies. A precise estimate of forest biomass is also important for other issues ranging from industrial forestry practices to scientific purposes. The individual tree-based biomass models serve as fundamental tools for precise estimates of carbon stock of species of interest in forest and agroforestry systems. We developed individual tree aboveground biomass models for Castanopsis indica using thirty-six destructively sampled tree data covering a wide range of tree size, site quality, growth stage, stand density, and topographic characteristics. We used diameter at breast height (DBH) as a main predictor and height-to-DBH ratio (a measure of tree slenderness) and wood density (a measure of stiffness and cohesiveness of wood fibres) as covariate predictors in modelling. We, hereafter, termed the biomass models with former two predictors as first category models (density independent models) and the models with all three predictors as second category models (density dependent models). Among various functions evaluated, a simple power function of the form \(y_{i} = b_{1} x_{i}^{{b_{2} }}\), in each category, showed the best fits to our data. This formulation, in each category, described most of the biomass variations (\(R_{adj}^{2}\) > 0.98 and RMSE < 72.2) with no significant trend in the residuals. Since both density dependent and density independent models exhibit almost similar fit statistics and graphical features, one of them can be applied for desired accuracy, depending on the access of the input information required by the model. Our biomass models are site-specific, and their applications should therefore be limited to the growth stage, stand density, site quality, stand condition, and species distribution similar to those that formed the basis of this study. Further research is recommended to validate and verify our model using a larger dataset with a wider range of values for site quality, climatic and topographic characteristics, stand density, growth stage, and species distribution across Nepal. 相似文献
19.
20.
蔡聪 《中南林业科技大学学报(自然科学版)》1995,(2)
采用目前测定物种多样性的几种方法，对马尾松、木荷、苦槠等针阔树混交林的乔木层物种多样性进行了测定和分析．结果表明，该混交林乔木层的物种多样性指数分别为３．３８６６，３．３４２７，０．５５９３，０．５１８７，０．６３４３和４７．９３８７％，均低于南亚热带常绿阔叶林和同一气候带的石灰岩常绿落叶混交林．对测定数据中均匀度（Ｅ）与种在个体数量上的变动系数（Ｃ）进行拟合，结果为：Ｅ＝－２．２０＋（５０．２０／Ｃ），ｒ＝０．９９７１． 相似文献