基于植被恢复的小流域生态系统服务功能评价研究
文献类型：学位论文
| 学位类别 | 博士 |
| 答辩日期 | 2009 |
| 授予单位 | 中国科学院研究生院 |
| 授予地点 | 陕西 |
| 导师 | 刘国彬 |
| 学位专业 | 生态学 |
| 中文摘要 | 本研究针对黄土丘陵区退耕还林草政策实施及西部植被生态恢复建设中存在的主要问题，以该区纸坊沟小流域为研究对象，以安塞站在该流域长期定位监测为基础，采用以空间序列代替时间序列的方法，通过野外调查、定位测定与室内分析，对该流域不同类型生态系统植被恢复过程中的植被特征和土壤质量变化规律进行了分析。在此基础上研究了不同类型生态系统服务功能物质量和价值量特征，初步构建了小流域生态系统服务功能价值评价指标体系，探索小流域生态系统服务功能价值评价的科学方法，并对植被恢复过程中的流域生态系统服务功能价值进行动态研究。为科学评价流域植被生态建设效果提供有效手段。主要结果如下：黄土丘陵区纸坊沟流域植被自然恢复动态特征为：恢复4年、12年、20年、28年和40年的草地生态系统物种组成由草本、小半灌木、灌木为优势种逐步过渡。不同恢复年限草地生态系统的盖度随植被恢复年限的增加而增加，当恢复到40年群落盖度有所减小。不同恢复年限的天然草地群落地上/地下生物量随着植被恢复演替时间的增加均显著性地增加(p<0.05)，生物量较盖度相比是个更敏感的指标。物种多样性指数随演替时间的延长先升高后降低；丰富度随演替进行不断升高，当植被恢复演替到28年之后，丰富度指数基本稳定；均匀度指数随演替进行而减小。在本研究区群落的丰富度和多样性变化与均匀度变化并不一致且有相反趋势。流域不同恢复年限草地生态系统0cm～20cm表层土壤容重随着恢复年限的增加而减小，不同类型生态系统的表层土壤容重大小顺序为天然灌丛<人工草地<乔木林地<果园 <人工梯田<退耕坡地。流域内不同类型生态系统表层土壤的总孔度变化规律与表层土壤的容重变化规律相反，表层土壤总孔度大小顺序为天然灌丛>人工草地>乔木林地>果园>人工梯田>退耕坡地。不同类型生态系统土壤的微团粒分形维数存在较大差异，其中天然草地和灌丛有助于土壤微团粒的形成。流域土壤分形维数的变化能很好地表征植被恢复演替过程中土壤的粗粒化和理化性质变化的趋势。分形维数可作为植被恢复演替过程中土壤质量定量评价的指标之一。流域不同恢复年限草地生态系统0cm～20cm表层土壤有机质和硝态氮均随着恢 复年限的增加而线形增加。土壤全氮、全磷、碱解氮和速效钾在植被恢复前期其含量增长较快，后期增长较慢，土壤氨态氮由于自身的不稳定性，随着植被恢复年限的变化不明显。在0cm～60cm深度土壤剖面上，土壤养分含量随着土层的加深而减小，表现出向表层富集的趋势。流域内不同类型生态系统0cm～20cm表层土壤有机碳含量的大小顺序为退耕坡地<人工梯田<人工草地<果园<天然草地<乔木林地<灌丛，土壤全氮、碱解氮和硝态氮的变化与土壤有机质的变化趋势相似，土壤氨态氮变化规律不明显。流域不同类型生态系统在3月～10月土壤呼吸速率均呈单峰型曲线，7、8月份的土壤呼吸作用显著高于其它月份(p<0.05)。不同类型生态系统土壤呼吸速率的变化比气温变化滞后，而与土壤温度变化一致。通过指数模型分析各类型生态系统的土壤呼吸速率与5cm深度地温的相关系数最高（乔木林地生态系统的土壤呼吸速率与10cm土层土壤温度相关系数最高），温度的变化能解释土壤 CO2 排放通量的75%以上。流域内不同类型生态系统Q10值的变化是2.0～3.4，平均值为2.6。流域不同类型生态系统在3月～10月的植物生长期土壤CO2排放总量分别为183.4 gC•m-2, 309.1 gC•m-2, 317.2gC•m-2, 221.3gC•m-2, 220.2 gC•m-2 和225.1gC•m-2。首次定量分析了黄土丘陵水土流失区典型流域基于植被恢复的流域生态系统各子系统和流域整体生态功能。流域生态系统服务功能总价值为727.12万元，流域土壤保持和固碳释氧的生态服务功能价值较高，流域单位面积生态系统服务功能价值为8792元/hm2，是我国和世界平均单位价值的近2倍。流域生态系统服务功能价值为林地>草地>灌丛>农地生态系统。在分析流域生态系统固碳释氧的服务功能时首次考虑土壤释放的CO2总量，将其从该项服务功能中扣除，以更准确地估算流域总的服务功能价值量。结合纸坊沟流域的自然资源状况和植被恢复演替特征，初步构建了基于植被恢复特征的流域生态系统服务功能评估指标体系和各类型生态系统服务功能的价值评价方法。分析了生态恢复工程中流域生态功能动态变化特征。为该区流域生态恢复环境效应综合评价提供科学依据和数据支持。流域总生态系统服务功能价值量从1980～1984年的647.07万元，变化到2005～2008年的727.12万元，其中2000～2004年间总服务功能价值量有所减小，2005～2008年达到最大值，流域总的生态系统服务功能价值量基本上随着植被恢复年限的增加而增加。 |
| 英文摘要 | Based on existing main problems of grain for green policy and vegetation restoration in hilly-gulled loess region, considered zhifanggou watershed of this region as the case study, also referred to the materials and data of long-term monitoring of Ansai research station, used the ecological method of special sequence instead of temporal, through reference collection, field investigation, ecological analysis, characters of vegetation and soil quality among different ecosystem types during the vegetation restoration processing in zhifanggou watershed were compared. Especially, the characters of vegetation and soil quality of grassland ecosystems with different restoration stages were analyzed. Meanwhile, the evaluating methods of different ecosystems ecosystem services in terms of physical quantity and economic values are proposed based on service assessment of individual ecosystem and environmental economic in zhifanggou watershed, then presented the term of ecosystem service evaluation of small watershed basing on vegetation restoration. The indicators and approach of ecosystem service evaluation were also studied to provide the methods of ecological rehabilitation benefits and situation. Finally dynamic research of ecosystem service evaluation was done grounded on vegetation restoration. The main results are as follows:The different restoration stages of grasslands such as 4 years, 12 years, 20 years, 28years and 40 years restoration were analyzed and the results showed that the component of grassland ecosystems from annual herbages to perennial herbages then appeared shrubs as the restoration processed. The coverage of grasslands with different restoration stages were increased as the restoration processed and then the coverage was decreased a little when the shrubs appeared. The aboveground and underground biomasses were increased significantly with the succession phase (p<0.05). The underground biomass of grasslands were increased with the soil depth increased. Biomass was a more sensitive index compared with coverage index. The diversity indices were first increased then decreased with the restoration processed, the richness indices were increased then stale in restoration year of 28, but evenness indices were decreased with the restoration processed. Bulk density of grasslands ecosystems were decreased with the restoration processed while the soil porosity condition becomes better in the latter restoration stages. Bulk density of upper layer was decreased as the restoration year increased. The soil total porosity, capillary porosity and porosity ratio were the opposite variety compared with bulk density but the same variety between non-capillary porosity and bulk density. There existed similar variety between bulk density and soil porosity condition of deeper soil layer and upper soil layer. Bulk density of different ecosystem types in sequence were natural shrub the human beings activities. In the 0cm～60cm soil depth, the deeper the lower soil nutrients content and the soil nutrients were higher in the upper layer of the soil. Soil organic carbon of 0cm～20cm soil layer of different ecosystem types in sequence were slope land < artificial terrace < artificial grassland < terrace < natural grassland < arbor forest < shrub land. Soil total nitrogen, available nitrogen and nitrate nitrogen had the similar changes as soil organic. The content of soil available potassium was higher because this watershed belonged to the potassium richness region. The nutrient content of deeper soil layer didn’t have significant changes like that of the upper soil layer.Soil CO2 flux plays an important role in regulating the responses of ecosystem and global carbon cycling. The results showed that monthly changes of soil respiration presented single peak curves, while the greatest values of soil CO2 flux rate were observed in July and August and decrease when the temperature was lower. Soil CO2 flux rates were better correlated with soil temperature at 5cm depth. Temperature could explain more than 75% of soil CO2 flux rate. While Q10 values were 2.1 to 2.4, which were close to the global mean value of Q10. The total quantity of soil CO2 flux from arbor, natural shrub, natural grassland, artificial grassland, terrace and slope land from the period of March to October were of 183.4 gC•m-2, 309.1 gC•m-2, 317.2gC•m-2, 221.3gC•m-2, 220.2 gC•m-2 and 225.1gC•m-2, respectively.Quantity of ecosystem service value of zhifanggou watershed was 7,271,200 yuan. The ecosystem service kinds of biodiversity production, soil conservation, carbon dioxide fixation and oxygen production were higher than other service kinds. And the ecosystem service value per area was 8,792 yuan/hm2, which was 2 times of the whole globe and our country. The sequences of total value of ecosystem services were forest ecosystem, grassland ecosystem, shrub land ecosystem and agriculture ecosystem. While considered the quantity of soil respiration when evaluated the ecosystem service of carbon dioxide fixation and oxygen release in order to calculate the total quantity of ecosystem service of zhifanggou watershed more exactly.Considering the condition of natural resource and the characters of vegetation restoration of zhifanggou watershed, established the indices framework of ecosystem service evaluation of small watershed basing on restoration vegetation in hilly-gullied loess region and the evaluation method of different ecosystem service kinds. The total quantity value of ecosystem service was 6,470,700 yuan during the year 1980 to 1984 and that value was 7,271,200 yuan during the year 2005 to 2008. But in the year 2000 to 2004 the value of ecosystem service in zhifanggou watershed was a little decreased because of the grain for green policy. During the period of 2005 to 2008 this value was highest of all the other time period. The value of ecosystem service in zhifanggou watershed was increased with the year of vegetation restoration processed. In order to develop ecological environment and sustainable use the natural resource of zhifanggou watershed, we must insist on the principal of exploitation and protection. Study on the value of ecosystem service evaluation of zhifanggou watershed basing on vegetation restoration can be used in nature reserve, ecological measurements planning and ecological zoning. It also ban be used an ecological approach, to some extent, toward regional healthier, stable and sustainable development. |
| 公开日期 | 2011-07-01 |
| 源URL | [http://ir.iswc.ac.cn/handle/361005/4117]  |
| 专题 | 水土保持研究所_水保所知识产出(1956-2013) |
| 推荐引用方式 GB/T 7714 | . 基于植被恢复的小流域生态系统服务功能评价研究[D]. 陕西. 中国科学院研究生院. 2009. |
入库方式： OAI收割
来源：水土保持研究所
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