Quantification and upscaling of greenhouse gas (GHG) fluxes from shallow waters, soils and trees in rural SE England.

对许多温室气体来源及其排放以及如何在空间和时间上扩大这些排放的理解不足，阻碍了向净零排放的竞赛。全球大气中的碳收支主要来自自然来源（如湿地）。排放量受到季节性温度和降雨量变化以及人为的排水、洪水和植被变化的影响。13 C/12 C和2 H/1H的比值有助于识别CH 4排放源和从地下到大气的传输路径。本研究旨在（i）量化一系列景观和浅水水体中的CH 4和CO2通量，（ii）阐明影响通量的环境因素，（iii）确定CH 4排放的同位素组成，以及（iv），加强大气测量的使用，以核实英国温室气体排放清单。项目成果将为减少温室气体排放的景观/环境管理决策提供信息。研究方法实地研究将在RBG基尤位于威克赫斯特的基地进行，在森林研究和横跨英格兰东南部的湿地地区的海峡围封。这将为量化温室气体通量和阐明不同类型土壤、树木和地表水的源-汇过程提供独特的机会。RHUL最先进的车载和便携式激光光谱仪系统、自动封闭箱和涡度协方差将测量不同景观的CH 4和CO2通量，并使用RBG在Wakehurst的新气象和土壤传感器无线网络确定潜在驱动因素。同位素比质谱法将用于测量样品中的13 C和D，以与移动的数据进行比较（见https：//www.royalholloway.ac.uk/research-and-teaching/departments-and-schools/earth-sciences/research-laboratories/greenhouse-gas-laboratory/）。基于数值和/或过程的模型将利用测量的通量、气候和土壤数据外推到区域景观，并预测未来的排放情景及其在气候变化中可能发挥的作用。

Scientific background The race toward net zero is hampered by poor understanding of many greenhouse gas sources and their emissions, and how to scale these up spatially and temporally. Uncertainties in global atmospheric carbon budgets arise mostly from natural sources (e.g. wetlands). Emissions are influenced by seasonal temperature and rainfall variability and anthropogenic changes in drainage, flooding and vegetation. Ratios of 13C/12C and 2H/1H help identify sources of CH4 emissions and transport pathways from subsurface to atmosphere.This studentship seeks to (i) quantify CH4 and CO2 fluxes from a range of landscapes and shallow water bodies, (ii) elucidate environmental factors that impact fluxes, (iii) characterise the isotopic composition of CH4 emissions, and (iv), enhance the use of atmospheric measurements to verify UK GHG emissions inventories.Project outcomes will inform landscape/environmental management decisions that reduce emissions of greenhouse gases.Research methodology Field studies will be conducted at RBG Kew's site at Wakehurst, the Straits Inclosure at Forest Research and at wetland regions across SE England. These will provide unique opportunities to quantify GHG fluxes and elucidate source-sink processes for different types of soils, trees and surface-waters. RHUL's state-ot-the-art vehicle-mounted and portable laser spectrometer systems, automated closed chambers and eddy covariance will measure CH4 and CO2 fluxes across different landscapes, with underlying drivers identified using RBG's new wireless network of meteorological and soil sensors at Wakehurst.Isotope ratio mass spectrometry will be used to measure 13C and D in samples for comparison with mobile data (see https://www.royalholloway.ac.uk/research-and-teaching/departments-and-schools/earth-sciences/research/research-laboratories/greenhouse-gas-laboratory/). Numerical and/or process-based models will utilise measured fluxes, climatic and soil data to extrapolate to regional landscapes, and make predictions for future emission scenarios and their likely role in climate change.