Determining regional-scale carbon losses from tropical peatlands using ISBAS-InSAR.

使用 ISBAS-InSAR 确定热带泥炭地的区域规模碳损失。

• 批准号: 2115310
• 金额: --
• 依托单位: University of Nottingham
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2115310
• 关键词: Determining; regional; scale; carbon; losses

80% of peatland in Indonesia and Malaysia (15% of Earth's soil carbon) is now drained for production of pulpwood and palm oil. Associated increases in peat decomposition and large-scale forest fires are now significant contributors to global greenhouse gas emissions. However, carbon losses from these processes and the impact of peatland drainage remain poorly quantified across SE Asia because of the challenging scale and inaccessibility of dense tropical peatland forests. Field-based subsidence measurements are therefore a spatially limited approach for assessing carbon losses from tropical peatlands. Space-based platforms offer the opportunity for regular and efficient pan-regional monitoring. A development in satellite interferometric synthetic aperture radar (InSAR), a technique that measures surface motion, has the potential to solve this problem. A new 'intermittent small baseline subset' (ISBAS) modelling technique, developed at the University of Nottingham, provides excellent coverage across almost all land surfaces irrespective of ground cover. This enables long term measurement of peatland surface motion across whole catchments, regions and countries. Importantly, the ISBAS technique is able to determine surface deformation under tropical forest canopy using C-band InSAR data, enabling continuous monitoring of surface motion ranging from 0.1 - 40 cm/yr at spatial scales 90x90m. Thus, space-based InSAR-derived motions should directly relate to tropical peatland carbon loss, allowing pan-regional assessment of carbon loss from otherwise inaccessible tropical peatlands. This is a novel approach as InSAR is yet to have been used to determine subsidence of tropical peatland sites. This project aims to determine whether rate of subsidence of the peat surface measured by InSAR is a proxy for rate of carbon loss in tropical peatlands in SE Asia. InSAR and field measurements of subsidence will be combined with peat carbon stock data using statistical regression modelling techniques to validate the use of subsidence as a proxy for carbon loss.

印度尼西亚和马来西亚80%的泥炭地（占地球土壤碳的15%）现在被排干用于生产纸浆木材和棕榈油。相关的泥炭分解和大规模森林火灾的增加现在是全球温室气体排放的重要因素。然而，由于热带茂密的泥炭地森林具有挑战性的规模和难以进入性，这些过程造成的碳损失和泥炭地排水的影响在整个东南亚仍然很难量化。因此，基于现场的沉降测量是评估热带泥炭地碳损失的一种空间有限的方法。天基平台为定期和有效的泛区域监测提供了机会。卫星干涉合成孔径雷达（InSAR）的发展，一种测量地表运动的技术，有可能解决这个问题。诺丁汉大学开发了一种新的“间歇小基线子集”（ISBAS）建模技术，可以在几乎所有陆地表面提供出色的覆盖，而不考虑地面覆盖。这使得能够长期测量整个集水区、区域和国家的泥炭地地表运动。重要的是，ISBAS技术能够利用c波段InSAR数据确定热带森林冠层下的地表变形，从而在90x90m的空间尺度上连续监测0.1 - 40 cm/年的地表运动。因此，基于insar的天基运动应与热带泥炭地碳损失直接相关，从而允许对原本无法进入的热带泥炭地的碳损失进行泛区域评估。这是一种新颖的方法，因为InSAR尚未用于确定热带泥炭地地点的沉降。该项目旨在确定InSAR测量的泥炭地表沉降率是否代表东南亚热带泥炭地的碳损失率。InSAR和现场沉降测量将与泥炭碳储量数据相结合，使用统计回归建模技术来验证沉降作为碳损失代理的使用。