不同時期土地利用生態系服務價值之比較評估

森林與人類生活與社會發展息息相關，近年來由於自然資源耗竭、氣候變遷等環境問題，人們開始關心森林生態系服務所提供的價值。隨著環境保護、永續發展的意識抬頭，對森林經營的方法亦開始轉變，不僅是重視林木產出而已，更考慮整體經營策略對整體生態服務的影響。而土地利用的變化亦會影響生態系服務的價值，透過了解生態系服務在空間上的分布，配合圖表紀錄其變化，便能幫助土地或森林經營者在執行決策時的參考依據。本研究利用InVEST生態系統服務評估工具，評估蓮華池試驗林的生態系服務價值在1995與2015年，碳吸存、水源涵養、土壤保持、水質淨化服務的分布情形。並透過預測未來20年土地利用情形以及不同策略下，評估生態系服務的變化與分布。最後透過綜合比較，以價值化的方式呈現生態系服務在不同情境下的變化。結果顯示比較2015與1995年，由於年降雨量嚴重影響水源涵養價值，且水源涵養價值占總體服務價值的9成左右，加上2015年森林的減少以及非植被用地增加，造成2015年蓮華池試驗林生態系服務價值減少93,881,968元；而比較2035年蓮華池試驗林維持現況下經營與造林策略下所造成生態系服務價值之差異，可知各項生態系服務價值在造林策略下皆較高。相較於2015年的總體生態系服務價值，仍以降雨量多寡為決定因素，當降雨量超過1,911mm時，2035年造林策略的總體生態系服務價值將超越2015年的總體價值。

關鍵字

InVEST ；生態系服務；土地利用；情境模擬

並列摘要

Forest is closely related to human society and infected our daily life. For the past few years, as the environmental problem increased, like depletion of natural resources and climate change, people started to concern about the value of ecosystem services. Since the rise of environmental awareness, the way how forest management works is also started to change. It considers not only forest output but also the relationship between strategies and ecosystem services. Furthermore, changes of land use will affect the value of ecosystem services. Understanding the spatial distribution of ecosystem services, and recording the differences of value may be a great help for forest manager on making decisions. The study takes Lien-Hua-Chih forest in Nantou as study area to investigate how ecosystem services change in different times. By using InVEST as study method, it evaluated carbon sequestration services, water yield, sediment retention and nutrient retention in 1995 and 2015. Then, forecasting the land use change in 2035 and making scenario simulation in order to analyze the changes of ecosystem services. Finally, the study will combine those results to make a comparison, and it will show how the value of ecosystem services changes in different periods and strategies. The result shows that from 1995 to 2015, due to the reduce of rainfall, the reduce of forest area and the increase of non-vegetated area, the value of forest ecosystem services loss around NTD $93,881,968. Comparing different strategies between “Non-strategy” and “Afforestation-strategy” of Lien-Hua-Chih forest in 2035, the study finds out that the “Afforestation-strategy” has a higher value of ecosystem services.