基于政策导向的岷江流域土地利用模拟及生态系统服务价值评估

Policy-oriented Land Use Simulation and Ecosystem Service Value Assessment in the Minjiang River Basin

有效测度与评估生态系统服务价值对制定生态补偿和土地整治政策、提高人类福祉具有重要意义。以岷江流域为研究区,基于2000、2010、2020年三期土地利用数据,运用PLUS模型和生态系统服务价值动态当量法对2030年研究区生态系统服务价值进行定量评估,并在充分考虑耕地保护中耕地质量这一关键性指标作为导向的基础上形成政策导向情景,与自然发展情景下的生态服务价值模拟进行比较分析。结果表明:(1)2030年不同情景下岷江流域土地利用空间分布格局基本一致,但土地利用变化呈现不同趋势。政策导向情景下建设用地面积增速得到有效控制,林地草地面积由减转增,耕地面积降速明显减缓,并且与自然情景相比有90.94 km2的平均等别以上耕地得到了有效保护,耕地质量得到有效保障;(2)2030年自然发展情景下岷江流域生态服务价值为1334.59亿元,政策导向情景下其生态服务价值为1347.65亿元,在空间上整体呈现北部与西南部高,中部与东南部低的态势。政策导向情景下生态服务价值变化冷点范围及浓度与自然发展情景相比显著降低,价值损失得到有效缓解;(3)耕地和林地的相互转化是未来岷江流域ESV损益的主要贡献来源,政策导向情景下耕地转向建设用地的贡献率与自然情景相比显著降低,仅为4.3%。研究结果可为岷江流域生态文明建设和可持续发展战略制定提供理论参考与辅助决策。

Effective measurement and assessment of ecosystem service values are crucial for formulating ecological compensation,land remediation policies,and improving human welfare.Taking the Minjiang River Basin as the study area,based on the three periods of land use data in 2000,2010,and 2020,the PLUS model and the dynamic equivalent method were applied to quantitatively assess the ecosystem service value of the study area in 2030.Additionally,the study formed a policy-oriented scenario based on the key indicator of arable land quality in arable land protection as an orientation.It was then analyzed in comparison with the simulation of ecological service value under the natural development scenario.The results showed that:(1)The spatial distribution pattern of land use in the Minjiang River Basin in 2030 remained consistent across different scenarios,but the trends in land use change differed.In the policy-oriented scenario,the growth rate of construction land area was effectively controlled,there was a shift from a decrease to an increase in the area of woodland and grassland.The decrease rate of arable land area was significantly slowed down.Compared with the natural scenario,90.94 km2 of arable land of average grade or higher was protected from encroachment,ensuring the effective preservation of arable land quality;(2)In 2030,the ecological service value of the Minjiang River Basin would be 133.459 billion yuan under the natural development scenario and 134.765 billion yuan under the policy-oriented scenario.The spatial distribution showed higher values in the northern and southwestern regions,and lower values in the central and southeastern regions.In the policy-oriented scenario,the range and concentration of cold spots of ecological service value changes were significantly reduced compared with the natural development scenario,and the loss of value was effectively mitigated;(3)The interconversion of cropland and forest land was the main source of contribution to future ESV gains and losses in the Minjiang River Basin,and the contribution of cropland to construction land was significantly lower under the policy-oriented scenario,compared with the natural scenario,at 4.3%.The results of the study can provide theoretical references and assist in decision making for the construction of ecological civilization and sustainable development strategies in the Minjiang River Basin.