森林生态系统碳蓄积量与年净碳汇估算研究

文章简述了森林生态系统碳蓄积量几种研究方法,并通过分析森林生态系统年固碳量与年释放碳量,估算了森林生态系统年净碳汇量;同时指出我国森林生态系统碳蓄积和碳循环研究存在的不足之处和发展前景,为实现林业低碳提供理论依据。       

中山市城市森林次生植被的群落学研究

采用样地调查方法,研究中山市城郊两种次生植被类型的物种组成和群落学特征。分析表明,人工促进恢复措施对于群落结构和林木个体生长速度有多方面的影响。马尾松、桉树、相思类在群落中的重要值已从纯林的重要地位退居于地带性乡土树种枫香、红锥、山杜英之后的次要地位,群落的物种丰富度和植物多样性指数有较大提高,森林群落的稳定性也得到增加。       

模拟地带性植被类型建设高质量城市植被

生态,地植物学的原理方法及其研究成果在城市绿地建设中有极为重要的指导作用,对提高城市绿化的总体水平,促进清洁、优美、舒适的生态城市的建设,具有现实意义1。       

山地型森林城市建设总体规划分析

文中基于ArcGIS栅格数据,运用景观指数分析软件Fragstats3.3,提取单个斑块面积(AREA)、斑块周长(PERIM)、形状指数(LSI)等景观指数对重庆市万盛区景观格局进行系统的分析;以此为基础进行万盛区森林城市建设总体规划,以体现不同山地型城市的差异。       

城市森林生态特点及病虫害综合管理

通过环境对城市森林生态系统影响的分析,结合目前植物病虫害的发生、发展特点及管理中的问题,由生态系统内部入手,从可持续控制的角度,探讨城市森林病虫害综合管理措施。       

湖南省城市森林苗木产销现状及走势分析

湖南是全国城市森林苗木生产大省,2007年全省城市森林苗木生产面积2.67万hm2,年销售额34亿元,分别占全省花木生产总面积及年销售额的80.2%、75.6%。"浏阳河百里花木产业带"的建成,使省会长沙成为中南地区最大的城市森林苗木生产与集散中心。全省各地苗市有喜有忧,花灌木和大、中规格全冠苗畅销,小规格乔木和截干移栽大树积压严重。苗木品种结构调整和标准化生产势在必行。       

南宁城市森林现状分析及发展策略

文章用SWOT法分析了南宁市城市森林的现状,探讨了南宁城市森林的建设布局,提出了发展城市森林的对策措施。       

南阳市森林生态系统服务价值评估及分析

通过对南阳市森林生态系统服务功能价值的评估,得出南阳森林生态系统服务功能总价值669.83亿元,此外还对其价值构成和不同森林类型单位面积的生态价值进行分析,并提出提高南阳市森林生态系统服务功能的建议。       

包头市城市森林绿地树种选择及效果评价

以包头市东河区、青山区、昆都仑区、九原区、开发区等五个城区中公园、行道、游园、小区、厂区、防护带等景观类型中树种和群落为调查对象,利用植物物种数、丰富度、多样性指数、重要值等指标对包头市城市绿地植物群落进行调查,用层次分析法评价,对包头市城市绿化树种现状进行分析。针对出现的问题提出在今后城市绿化树种增加种类增加层片和季相,提高绿化的稳定性及不同时间的观赏要求,加大对乡土树种的开发和应用,提高适应性,以减少经济造价。       

广州市森林碳汇分析

文章根据广州市林业"十一五"发展规划和"青山绿地工程"的执行状况,以广州市林业"一城三地五极七带多点"的森林生态网络体系为基础,选择典型森林类型;在对广州市林业碳储量现状与固碳潜力、化石燃料消耗结构动态及发展趋势综合分析的基础上,对广州市现有森林的碳汇功能作出评价,并据此提出提高林业碳汇能力的几点建议。       

Estimation of the carbon storage of forest vegetation and carbon emission from forest fires in Heilongjiang Province,China

The forest resource of Heilongjiang province has important position in china. On the basis of the six times of national forest inventory data （1973-1976, 1977-1981, 1985-1988, 1989-1993, 1994-1998, 1999-2003） surveyed by the Forestry Ministry of P. R. China from 1973 to 2003, the carbon storage of forests in Heilongjiang Province are estimated by using the method of linear relationship of each tree species between biomass and volume. The results show that the carbon storage of Heilongjiang forests in the six periods （1973-1976, 1977-1981, 1985-1988, 1989-1993, 1994-1998, 1999-2003） are 7.164×10^8 t, 4.871×10^8 t, 5.094×10^8 t, 5.292×10^8 t, 5.594×10^8 t and 5.410×10^8 t, respectively., which showed a trend of decreasing in early time and then increasing. It indicated that Heilongjiang forests play an important role as a sink of atmospheric carbon dioxide during past 30 years. Based on the data of forest fires from 1980 to 1999 and ground biomass estimation for some forest types in Heilongjiang Province, it is estimated that the amount of mean annual consumed biomass of forests is 391758.65t-522344.95t, accounting for 6.4%-8.4% of total national consummation from forest fires, and the amount of carbon emission is 176 291.39t-235 055.23t, about 8% of total national emission from forest fires. The emission of CO2, CO, CH4 and NMHC from forest fires in Heilongjiang Province are estimated at 581761.6-775682.25 t, 34892.275-46523.04 t, 14091.11-18788.15 t and 6500-9000 t, respectively, every year.     

Estimation of biomass and carbon stocks in plants,soil and forest floor in different tropical forests

An accurate characterization of tree carbon (TC), forest floor carbon (FFC) and soil organic carbon (SOC) in tropical forest plantations is important to estimate their contribution to global carbon stocks. This information, however, is poor and fragmented. Carbon contents were assessed in patula pine (Pinus patula) and teak (Tectona grandis) stands in tropical forest plantations of different development stages in combination with inventory assessments and soil survey information. Growth models were used to associate TOC to tree normal diameter (D) with average basal area and total tree height (H_T), with D and H_T parameters that can be used in 6–26 years old patula pine and teak in commercial tropical forests as indicators of carbon stocks. The information was obtained from individual trees in different development stages in 54 patula pine plots and 42 teak plots. The obtained TC was 99.6 Mg ha⁻¹ in patula pine and 85.7 Mg ha⁻¹ in teak forests. FFC was 2.3 and 1.2 Mg ha⁻¹, SOC in the surface layer (0–25 cm) was 92.6 and 35.8 Mg ha⁻¹, 76.1 and 19 Mg ha⁻¹ in deep layers (25–50 cm) in patula pine and teak, respectively. Carbon storage in trees was similar between patula pine and teak plantations, but patula pine had higher levels of forest floor carbon and soil organic carbon. Carbon storage in trees represents 37 and 60% of the total carbon content in patula pine and teak plantations, respectively. Even so, the remaining percentage corresponds to SOC, whereas FFC content is less than 1%. In summary, differences in carbon stocks between patula pine and teak trees were not significant, but the distribution of carbon differed between the plantation types. The low FFC does not explain the SOC stocks; however, current variability of SOC stocks could be related to variation in land use history.     

鸡公山自然保护区森林植被生物量及活碳蓄积量研究

运用鸡公山科学考察资料及1999年森林资源清查资料,采用森林材积源生物量推算方法研究了鸡公山森林植被生物量及其活碳蓄积量。结果表明:鸡公山森林植被生物量总值为309 202t,平均森林植被生物量为111.7t／hm2,高于全国平均水平(77.4t／hm2);鸡公山森林植被的总活碳蓄积量为154 601t,平均活碳密度为56MgC／hm2,高于中国森林植被活碳密度的平均水平(38.7 MgC／hm2),但低于全球平均碳密度(86MgC／hm2)。不同林型活碳蓄积密度分析结果表明,马尾松、杉木和栎类林木的活碳蓄积密度分别为30MgC／hm2,39 MgC／hm2和70MgC／hm2,均高于全国同类型森林植物的活碳蓄积密度的平均值,而次生阔叶混交林的碳蓄积密度略低于全国平均水平。鸡公山自然保护区67％的森林为中龄林,27％的森林为幼龄林,在增加碳蓄积方面还有巨大的潜力。     

紫金山森林固氮释氧量的研究

基于紫金山森林资源清查资料,比较历年的森林面积和蓄积量,分析紫金山森林增长速度快慢的原因,并从汇总出的2006年各优势树种蓄积量数据中,采用生物量换算因子连续函数法等研究方法,核算出森林的最新固碳释氧量数据,突出自2004年大型环境综合整治以来,紫金山森林生态系统中植物地上部分固碳释氧的生态功能。结果表明:固碳量为176095.9t,释氧量为129641.2t,为今后紫金山植物栽植和配置、南京城市森林规划和建设提供参考。       

Relationship between vegetation carbon storage and urbanization: A case study of Xiamen, China

Rapid growth of the Chinese urban population and the expansion of urban areas have led to changes in urban forest structure and composition, and consequently changes in vegetation carbon storage. The purpose of this study is to quantify the effects of urbanization on vegetation carbon storage in Xiamen, a city located in southern China. Data used for this study were collected from 39,723 sample plots managed according to the forest management planning inventory program. Data from these plots were collected in 4 non-consecutive years: 1972, 1988, 1996 and 2006. The study area was divided into three zones, which were defined according to their level of urbanization: the urban core, the suburban zone, and the exurban zone. Total vegetation carbon storage and the vegetation carbon density for each study period were calculated for each zone. Our results show that urban vegetation carbon storage has increased by 865,589.71 t during the period from 1972 to 2006 (34 years) in Xiamen, with a rapid increase between 1972 and 1996, then relatively little change between 1996 and 2006. The increase in vegetation carbon storage is mainly due to the large percentages of the suburban and exurban areas which exist in Xiamen city, and the implementation of reforestation programs in these two zones. The percentage of total regional carbon storage in the city center (urban core), suburbs and exurbs was 5%, 23% and 72%, respectively. This demonstrates that the exurbs store the majority of vegetation carbon, and thus play a critical role in the vegetation carbon storage of the study area. The intensification of urbanization in the future will likely expand the urban core and reduce the area of the suburbs and exurbs, and thus potentially decrease total vegetation carbon storage. This article concludes with a discussion of the implications of these results for vegetation carbon management and urban landscape planning.     

西藏墨脱县森林植被生物量与碳储量分析

基于墨脱县森林资源二类调查数据等材料,采用材积源生物量法以及生物量转换连续因子法等经验模型,分不同森林植被类型计算各个小班的生物量并综合;再根据不同森林植被类型的含碳率计算各个小班的碳储量以及各森林植被类型的碳密度。结果表明,墨脱县实际控制区总的森林植被生物量为77 582 750.1 t,全县单位面积平均生物量为177.61 t/hm2;总碳储量为39 355 414.3 t,全县碳密度平均为90.10 t/hm2。从结果来看,墨脱县的森林生物生产力较高,森林资源质量较好,尤其是云杉(冷杉)的单位面积平均生物量高达311.60 t/hm2,质量非常好;全县单位面积平均生物量、碳密度均为针叶树较阔叶树大。     

岛东林场森林碳汇能力分析与评价

为了探讨森林碳汇能力、森林碳汇贮存量,该研究利用IPCC(政府间气候变化专门委员会)制定计算方法,通过对岛东林场2009年森林资源二类清查数据进行分析,得出目前岛东林场碳汇蓄积量约31.4万t。数据分析结果表明,当前岛东林场森林经营方式不能满足国家层面上以应对全球气候变化为目的的多功能森林经营要求,也不能满足海南国际旅游岛建设中对森林游憩资源开发需求,在这基础上提出对岛东林场人工林科学合理的近自然化改造模式。     

Mapping and spatial uncertainty analysis of forest vegetation carbon by combining national forest inventory data and satellite images

Forests play an important role in carbon sinks and mitigation of atmospheric concentrations of carbon dioxide and greenhouse effect. Given that sample plots used for collection of forest carbon observations are often much smaller than the map units of forest carbon at regional, national, and global scales, scientists are currently experiencing two challenges. The first challenge is to produce reliable maps of forest carbon using the data from inconsistent sizes of plots and image pixels. Also, because estimates of forest carbon normally contain uncertainties, the second challenge is to accurately model propagation of uncertainties from input data to output results. In this study, a methodology for mapping and analyzing spatial uncertainty of forest carbon estimates was developed to address these challenges. The methodological framework consisted of two methods. The first one was up-scaling method that combined and scaled up existing national forest inventory plot data and satellite images from smaller sample plots and image pixels to larger map units. The second one was spatial uncertainty analysis and error budget method that entailed modeling propagated uncertainties through a geostatistical mapping system. A case study using 46 permanent national forest inventory plots from Wu-Yuan County, Jiangxi, China, was undertaken to test this methodology. The results showed that this method reproduced not only the spatial distribution of forest carbon but also the spatial pattern of variances of its estimates and was able to quantify the contributions of uncertainties from the field plot data and satellite images to the uncertainties of forest carbon estimates. Thus, this study, to some extent, overcame the gaps that currently exist in the generation and assessment of forest carbon estimation maps. Moreover, the results showed that in this case study, the variation of the band ratio defined as (TM2 + TM3 + TM5)/TM7 contributed more uncertainties to the estimates of forest carbon than the variation of the plot data. In addition, we also found out that the product of the input plot forest carbon variance and the band ratio variance, implying the interaction between these two variables, reduced the uncertainties of the forest carbon estimates.     

Potential knowledge gain in large-scale simulations of forest carbon fluxes from remotely sensed biomass and height

Global vegetation models (GVMs) simulate CO₂, water and energy fluxes at large scales, typically no smaller than 10 × 10 km. GVM simulations are thus expected to simulate the average functioning, but not the local variability. The two main limiting factors in refining this scale are (1) the scale at which the pedo-climatic inputs - temperature, precipitation, soil water reserve, etc. - are available to drive models and (2) the lack of geospatial information on the vegetation type and the age of forest stands. This study assesses how remotely sensed biomass or stand height could help the new generation of GVMs, which explicitly represent forest age structure and management, to better simulate this local variability. For the ORCHIDEE-FM model, we find that a simple assimilation of biomass or height brings down the root mean square error (RMSE) of some simulated carbon fluxes by 30-50%. Current error levels of remote sensing estimates do not impact this improvement for large gross fluxes (e.g. terrestrial ecosystem respiration), but they reduce the improvement of simulated net ecosystem productivity, adding 13.5-21% of RMSE to assimilations using the in situ estimates. The data assimilation under study is more effective to improve the simulation of respiration than the simulation of photosynthesis. The assimilation of height or biomass in ORCHIDEE-FM enables the correct retrieval of variables that are more difficult to measure over large areas, such as stand age. A combined assimilation of biomass and net ecosystem productivity could possibly enable the new generation of GVMs to retrieve other variables that are seldom measured, such as soil carbon content.     

Tree diversity and carbon stocks of some major forest types of Garhwal Himalaya,India

Four forest stands each of twenty major forest types in sub-tropical to temperate zones (350 m asl–3100 m asl) of Garhwal Himalaya were studied. The aim of the study was to assess the stem density, tree diversity, biomass and carbon stocks in these forests and make recommendations for forest management based on priorities for biodiversity protection and carbon sequestration. Stem density ranged between 295 and 850 N ha⁻¹, while total biomass ranged from 129 to 533 Mg ha⁻¹. Total carbon storage ranged between 59 and 245 Mg ha⁻¹. The range of Shannon–Wiener diversity index was between 0.28 and 1.75. Most of the conifer-dominated forest types had higher carbon storage than broadleaf-dominated forest types. Protecting conifer-dominated stands, especially those dominated by Abies pindrow and Cedrus deodara, would have the largest impact, per unit area, on reducing carbon emissions from deforestation.