【作者】 王迪生；

【导师】 翟明普；

【作者基本信息】 北京林业大学 ， 森林培育， 2010， 博士

【摘要】 当前,随着国际社会对气候变化的高度关注,二氧化碳减排成为国际气候谈判的重要主题,各国都在积极实施碳减排的措施,降低碳排放量。国内外关于全球或区域范围的碳存储、碳减排、碳汇量、碳增汇等研究方兴未艾,有关森林、土壤、农业、草原等碳汇研究和测算开展得比较早,成果比较丰富。但是从区域或微观尺度研究并测算城市园林绿地内植被和土壤的碳储量,还罕见报道。城市园林绿地内储存了一定数量的碳。园林植物每年通过吸收并固定二氧化碳,对于净化城市空气,减少空气中二氧化碳,维护良好的城市人居环境,维持城市碳氧平衡和生态平衡发挥着重要作用。因此城市园林绿地的生态环境功能问题已成为新时期城市园林、城市林业的重要研究内容和课题,研究北京市城区园林绿地净碳储量及碳平衡状况,对于城市的生态环境建设管理、城市区域碳储量计测方法和丰富全球碳计划具有重要的理论和现实意义。本文对城市生态环境、园林植物的生态环境功能、园林与林业的异同和殊途同归、城市林业的特征、城市园林绿地的碳汇计测评价等问题进行了分析探讨。在此基础上,开展了北京城区园林绿地范围内,植物直径和树高株数分布、植物生物量计测、净碳储量及碳平衡、增汇潜力、政策建议的系列研究,核心研究是园林植物生物量的估测和城区园林绿地现有的净碳储量。本研究的主要方法是,(1)采用抽样调查方法共调查138个样点、2789株样木资料,通过统计分析、数学模拟等手段,估计探讨主要类型园林植物的平均大小和结构分布,解决园林绿化普查中缺少植物个体大小的不足;(2)运用22株各类型平均标准木的分部位实际测定值,研究探讨植物各部位生物量分布规律,测算北京市现有园林植物生物量;(3)运用10种平均标准木直径生长过程资料,研究探讨北京城区园林乔木植物的年均直径生长量和年均植物生物量增长量;(4)运用22株各类型平均标准木分部位含碳率测定数据,分析探讨北京城区主要园林植物及分部位的含碳率变动和分布规律,采用生物量方法研究测算园林植物净碳储量和净碳密度;(5)运用40个园林绿地土壤剖面的分层样品测定数据,分析验证园林绿地土壤分层碳储量的分布规律,研究测算了北京城区现有园林绿地土壤总碳储量、碳储量密度。最终研究测算北京市园林绿地范围内的总净碳储量、总碳密度,每年的净增碳汇量;从北京市碳排放和生物固碳吸附碳两方面分析测算北京市碳平衡情况,探讨园林绿地的增汇潜力,并对北京城区生态环境建设和碳减排相关工作提出政策、技术建议。研究主要结果表明,(1)北京城区园林植物中小径组的植物数量占绝大多数,即96.1%。从乔木来看,大(≥30cm)、中(10-30cm)和小(≤10cm)径组的株数比率为:25.9%、49.7%和24.4%,估测株数分别是294.26万株、564.65万株和277.21万株;(2)北京城区现有园林植物平均直径、树高和冠幅直径都不大,以落叶乔木类为最大。其中,常绿乔木类分别是13.5cm、5.8m、3.1m;落叶乔木类分别是24.2cm、10.5m、6.0m;(3)平均标准样木法测定园林植物净生物量在实践中是合适的。北京城区(含远郊区县建制镇)园林植物现有净生物量为181.86万t,其中城八区为129.12万t,平均40.95t/hm~2;(4)园林植物含碳率比较稳定,与其它研究结果相似。北京城区园林植物平均含碳率为0.486,范围0.4—0.6。常绿类植物0.51大于落叶类0.48,乔木类植物0.49大于灌木类0.47,按部位大小排序一般为:树叶、树干、树枝、树根、树皮;(5)生物量方法适合测定城市园林净碳储量,城市园林绿地净碳储量比较丰富。北京城区现有园林绿地范围内总净碳储量是371.16万t,平均每公顷绿地92.46t/hm~2。园林绿地内的净碳主要是植物碳和土壤碳,现有园林植物的净碳储量88.82万t,平均每公顷22.1t/hm~2;现有园林土壤碳储量为282.31万t,平均每公顷土壤碳储量70.33t/hm~2;土壤碳是园林植物的3.18倍,占总净碳储量的77.9%;(6)城市园林绿地年度生物量和净碳储量增长明显。现有园林乔木植物胸径年生长量为0.8cm,年生物量净增长6.6万t,北京市城区年净碳储增长量约为4.5万t。平均每公顷绿地年生物量增长2.09t/hm~2,碳储量增长1.12t/hm~2。(7)北京市年度碳排放和碳吸收还不平衡。北京市每年的碳排放量约为1.4亿t,人均7.2t。北京市森林、园林植物等每年共计可以吸收二氧化碳7130.8万t,占北京市每年总排放量的53.2%,效果相当显著,但还不平衡,具有很大潜力。研究主要建议,(1)城市生态环境建设是现代化北京应该高度重视的问题,是宜居城市和生态文明的必然要求。建议从科学规划、强化自然格局、多样化生态系统、恢复自然河道与湿地、城郊一体化、绿地开放等方面改变观念,持续发展,促进城市生态和谐;(2)积极采取科学合理有序的应对措施,减少碳减排,增加碳储量。可以从宣传普及碳汇知识、科学研究与推广科技成果、碳贸易、发展低碳与可再生能源、控制人口增长、倡导绿色消费、征收碳税、发展生物固碳等方面,采取得力措施,减轻因CO~2的排放积累造成的城市一系列生态环境问题,实施积极的温室气体减排政策,为城市发展和人类社会作出应有的贡献。(3)城市园林绿化普查方法简单,调查内容少,类型和树种划分不科学,普查数据利用价值不高,建议园林绿化普查与林业资源调查同步进行。重新研究设定园林绿化普查的指标、项目和调查技术方案,测定胸径、树高、生物量等指标,加强城市生态环境效益的评估,发挥城市园林绿地对城市生态环境的主体作用。更多还原

【Abstract】 At present,with the international community highly concerned about climate change,carbon dioxide emission reduction has become an important topic of climate negotiations,countries are actively implementing carbon emission reduction measures to reduce carbon emissions.At home and abroad about the scope of a global or regional carbon storage,the volume of carbon sinks,carbon emission reduction,carbon sinks,such as research by the ascendant,the forests,soils,agriculture, grassland,such as carbon sinks research and carry out than earlier estimates,the results are also relatively rich.But research on the measurement method of city gardens green vegetation and soil carbon storage from a regional perspective,the micro-view also were very rare.Urban landscape green stores a certain amount of carbon each year through the absorption of carbon dioxide,and plays an important role on purification of urban air,reduce carbon dioxide, maintaining a good city living environment,carbon and oxygen balance in the town,the maintenance of ecological balance in the city.Therefore urban landscape green ecological functions has become the important content and topics on new era city garden and city forestry.Research on net carbon storage and carbon balance in Beijing urban landscape green land,for the city’s ecological environment construction management,urban regional carbon measurement methods and the global carbon plan,is an important theoretical and practical significance.In this paper,a systematic analysis of the city’s ecological environment,the ecological environment features of landscape plants,differences and similarities between gardens and forest and are achieving the same,characteristics of urban forestry,measuring the evaluation questions of carbon sinks on urban landscape green land,etc,were investigated.On this basis,a series of research on plant diameter/heigh distribution,plant biomass,net carbon reserves,carbon balance,the potential of increasing carbon sink and policy recommendations were carried out in Beijing urban landscape green.The main research method is:(1) 138 simple points and 2789 sample trees were investigated by sampling,statistical analysis,simulation methods.This article explored the main types of landscape plants and their average size and distribution to resolve the lack of plant size in landscape survey;(2) By the method of all types average standard wood of 22 plants different parts actual determination value,plant parts biomass distribution law was firstly explored and the biomass of landscape plants in Beijing was calculated;(3) According to 10 plants mean standard tree diameter growing,the growth of Beijing garden arbor diameter and annual plant biomass increment were investigated;(4) Beijing urban main garden plant and each part of plant carbon content rate change and distribution law were discussed firstly by all types average standard wood data of 22 plants carbon content rate.Garden plant net carbon reserves and net carbon density were calculated by biomass method;(5) According to 40 garden green space soil profiles layered sample determination data,distribution law of soil layer carbon reserves were measured.Soil total carbon reserves and carbon density in Beijing urban were calculated; Present total net carbon reserves,carbon density and annual net increasing carbon sequestration of Beijing garden green space were calculated;From two sides of Beijing city carbon emission and biological carbon fixation adsorption,Beijing city carbon balance and increasing carbon sequestration potential was discussed.Associated policies and technological suggestions on Beijing urban biological environment construction and carbon emission reduction were put forward.The results showed that:(1) For arbor,the diameter ratio of large(＞30cm),middle(10-30cm) and small(＜10cm)are 25.9%,49.7%and 24.4%in Beijing city(including 8 districts),estimated tree numbers are 2.94×10~6,5.64×10~6 and 2.77×10~6;(2) The average diameter,average tree height and average crown diameter of the existing landscape plants are not large,these of the deciduous arbor is the largest.the average diameter,average height and average crown diameter of the evergreen are respectively 13.5cm,5.8m,3.1m;and these of the deciduous are respectively 24.2cm,10.5m,6.0m;(3) A net biomass of the existing landscape plants are 1.82×10~6 t in Beijing(including the outer suburbs), in which,Beijing City(including 8 districts) occupied 1.29×10~6t with an average of 40.95 t/hm~2;(4) The mean carbon content rate of Beijing landscape plants was 0.486,with a ranging from 0.4 to 0.6. The evergreen are higher than the deciduous and the arbor are higher than the shrub The order according to part size is:leave(trunk),trunk(leave),branch,root and cortex;(5) The total carbon reserves of the existing green space are 3.71×10~6 t with an average of 92.46 t/hm~2,these reserves are mainly plant and soil carbon(77.9%).Existing carbon reserves in Beijing city green space are 8.88×10~5 t,with an average of 22.1 t/hm~2 Existing landscape soil carbon reserves are 2.82×10~6 t,which is 3.18 times more than that of landscape plants with an average of 70.33t / hm~2;(6)The annual growth of existing arbor’s breast diameter was 0.8 cm,6.6×10~4 t for the annual biomass.The net increase of carbon reserves was about 4.5×10~4 t in Beijing.The per hectare growth of biomass and carbon reserves were 2.09 t and 1.12 t respectively;(7) Annual carbon emission of Beijing was 1.4×10~8 t and per capital was 7.2 t.Beijing city forest and garden plant could absorb 7.13×10~7 t CO~2,which occupied 53.2%of emission.The effect of emission reduction was obvious with great potential.The study also suggested that,(1) Urban ecological environment construction is should attach great importance to the problem for modern Beijing,and is the inevitable requirement of livable cities and ecological civilization.Recommendations that the concept of the scientific planning,strengthen the natural pattern,diverse ecosystems,restoration of natural river channels and wetlands,suburban integration,opening green and so on,be should changed,it will be useful of sustainable development, promoting urban ecological harmony.(2) Actively adopt a scientific and rational and orderly response measures to reduce carbon emissions and increase carbon storage.The Government should take effective measures to reduce CO~2 emissions due to accumulation of a series of ecological urban environmental problems,and implement a proactive policy of greenhouse gas emissions for urban development and make due contributions to human society,From outreach carbon sinks of knowledge, scientific research and popularization of scientific and technological achievements,carbon trading, developing low-carbon and renewable energy sources,control population growth,promoting green consumption,carbon tax,development of bio-carbon sequestration,etc.(3) City landscape survey method is not scientific,the use of census data value is not high.The study proposed the survey of landscape greens and forestry resources carried out simultaneously,re-formulated the landscape green Census indicators,projects and investigate technology options to determine the diameter at breast height,tree height,biomass and other indicators,to strengthen the city’s ecological assessment of environmental benefits,to exert on the town’s main role in the ecological environment.更多还原