气候变化背景下未来中国草地生态系统服务价值时空动态格局

Temporal-Spatial Dynamic Pattern of Grassland Ecosystem Service Value under the Background of Climate Change in the Future in China

气候变化已经并将继续对中国自然生态系统和人类社会产生广泛而深远的影响,成为人类经济社会发展的风险。为了解未来中国草地生态系统服务价值的时空动态格局以及揭示气候变化的可能影响,以采用CEVS模型计算得出的NPP为基础,根据Costanza等提出的生态系统服务价值计算方法,分析了基准期(1971—2000年)及未来(2021—2050年)RCP 4.5(中低排放)和RCP 8.5(高排放)情景下中国草地生态系统服务价值时空动态变化特征。结果表明,基准期及未来RCP 4.5和RCP 8.5情景下中国草地生态系统服务总价值均呈增加趋势,年平均值分别为1.93万亿、2.26万亿、2.27万亿元。其空间分布状况与水热条件的分布趋势一致,均表现出从西北向东南逐渐递增的分布格局。未来总价值除了在西藏西北部及新疆中部小范围内表现为减少外,在其他地区均呈增加趋势。增幅分布模式与中国人口分布以胡焕庸线划定的基本格局相似,表现为西北增幅小,东南增幅大;大部分地区增幅比例在30%以内,少数为30%~60%,60%以上非常稀少。中国草地生态系统服务各功能构成项对总价值的贡献率依次为:土壤形成与保护(26.9%)>废物处理(18.1%)>生物多样性保护(15.1%)>气候调节(12.4%)>气体调节=水源涵养(11.0%)>食物生产(4.1%)>原材料生产(0.7%)>娱乐文化(0.6%),即物质产品产出价值仅占4.8%,非物质价值占95.2%。该研究揭示了未来30年中国草地生态系统服务价值的时空格局动态演化及其对气候变化的可能响应,在一定程度上填补中国在生态系统服务价值动态、定量预估方面的空白现状,这对于未来科学应对气候变化、合理利用草地资源、加强生态环境建设具有一定的指导意义。

Climate change is already and will continue to impact on our natural ecosystems and human society extensively and profoundly, and therefore will be the risk of human economic and social development.Temporal and spatial dynamic characteristicsof grassland ecosystem service value from 1971 to 2000 as a baseline period and from 2021 to 2050 under RCP 4.5（middle and low emissions） and RCP 8.5（high emission） scenarios in China were analyzed, in order to understand spatio-temporal dynamic pattern and reveal the impact of climate change in the future. The calculation methods put forward by Costanza, etc. and the NPP data calculated by using the CEVSA ecological processes model were used. The results showed that the total grassland ecosystem service values showed an increasing trend, with the annual mean of 1.93×1012, 2.26×1012 and 2.27×1012 yuan, respectively for baseline period and for future （under RCP 4.5 and RCP 8.5 scenarios）. Total value displayed a space pattern of gradualincreasing from northwest to southeast, which was consistent with the distribution pattern of hydrothermal conditions. The values decreased in relatively little areas i.e., in the west and north of Tibet and the middle of Xinjiang, but increased in other regions in the future, relative to the baseline period. A patter of greater increase amplitude in the southeast and smallerones in the northwest was observed, which was similar to the Hu Huanyong line population distribution pattern in China. The increase percentage was within 30% in most of areas, was in the range of 30%-60% in a few regions, and was more than 60% in very few regions. The contribution rates of ecosystem service value for individual function were in an order of soil formation and protection （26.9%）〉waste treatment （18.1%）〉biodiversity protection （15.1%）〉climate regulation （12.4%）〉gas regulation=water conservation （11.0%）〉food production （4.1%）〉raw material production （0.7%）〉recreation and culture （0.6%）. Therefore, material products accounted for only 4.8% of thevalues, and intangible value accounted for 95.2%. This study revealed a dynamic evolution pattern of grassland ecosystem service values in the future and its corresponding response to climate change in China. It has some guiding significance for adapting to climate change, utilizing forest resources rationally, and strengthening ecological environment construction. To a certain extent, it fills the blank of the dynamic and quantitative prediction of ecosystem service value in China at present.