Water management and mitigation of greenhouse gas emissions from agricultural lowland peatlands

NERC：Benjamin Freeman：NE/R010218/1全球泥炭地是我们最大的陆地碳库。泥炭地在积水条件下形成，但已被广泛排水，以允许农业使用。排水泥炭由于其高营养含量和储存植物根系容易获得的水的能力而提供了高产的农业用地。然而，为了农业生产而对泥炭地进行排水也会让氧气进入土壤，这会刺激微生物，这些微生物开始分解构成泥炭的有机物质。这种微生物活动导致大量温室气体（GHG）排放和泥炭中储存的碳的损失，从而导致气候变化。在加拿大和英国，低地泥炭地提供了高产的农业土壤，并在经济上重要的蔬菜作物的生产中发挥着关键作用。因此，泥炭地农业在气候、经济和粮食安全问题之间存在固有的权衡，这给决策者和土地管理者带来了挑战。该研究项目旨在帮助解决负责任的泥炭地管理道路上的两个关键挑战。首先，我们将计算作物的碳足迹，其中包括来自泥炭土壤分解的温室气体排放。这将提高我们对泥炭地农业所涉及的权衡的理解，并有助于突出减少粮食生产过程中温室气体排放的关键机会。其次，我们将使用建模方法来更好地了解如何使用中间地下水管理来帮助减少农业泥炭地的温室气体排放的实用性。减少排水深度，从而提高地下水略接近田间表面，减少了通气的泥炭土的体积，并减少了地下水位以下地层中的微生物活动。因此，这已被提议作为一种选择，以减少泥炭土壤的温室气体排放，同时允许农业生产继续进行。然而，如果地下水和供水管理不当，可能会对农民造成严重后果，因为水资源短缺和地表水泛滥会损害作物和生计。建模将允许模拟不同水管理方案的影响。这将有助于确定实施地下水中期管理的主要挑战和最大限度地提高其效力的机会。鉴于制定负责任的农业低地泥炭地管理战略的重要性，这项研究将有助于告知政策和行业的决策者，使英国和加拿大受益，并有助于保护这些宝贵的自然资源。

NERC : Benjamin Freeman : NE/R010218/1Global peatlands are our largest terrestrial carbon store. Peatlands form under waterlogged conditions but have been widely drained to allow agricultural use. The drained peat provides highly productive agricultural land thanks to its high nutrient content and capacity to store water that is readily available to plant roots. However, drainage of peatlands to enable agricultural production also allows oxygen into the soil and this stimulates microbes which begin to break down the organic material that makes up the peat. This microbial activity results in substantial greenhouse gas (GHG) emissions and the loss of the carbon stored in the peat, contributing to climate change. In both Canada and the UK, lowland peatlands provide highly productive agricultural soils and play a key role in the production of economically important vegetable crops. Consequently there is an inherent trade-off in peatland agriculture between climate, economic and food security concerns, which creates a challenge for policy makers and land managers. This research project sets out to help address two key challenges on the road to responsible peatland management. Firstly we will calculate carbon footprints for crops which include the GHG emissions derived from the breakdown of the peat soil. This will improve our understanding of the trade-offs involved in peatland agriculture and help highlight key opportunities to reduce GHG emissions in the food production process. Secondly, we will use modelling approaches to understand better the practicalities of how intermediate groundwater management might be used to help reduce GHG emissions from agricultural peatlands. Reducing the drainage depth and thus raising the groundwater slightly nearer to the field surface reduces the volume of peat soil that is aerated and reduces microbial activity in layer below the water table. Therefore, this has been proposed as an option to reduce GHG emissions from peat soils, whilst allowing agricultural production to continue. However, if the groundwater and water supply are not managed correctly this could have serious consequences for farmers, as water shortages and surface water flooding can damage crops and livelihoods. Modelling will allow simulation of the effects of different water management scenarios. This will allow identification of both the key challenges to implementation of intermediate groundwater management and opportunities to maximize its effectiveness. Given the importance of developing responsible management strategies for agricultural lowland peatlands, this research will help inform decision makers in policy and industry, benefiting both the UK and Canada, and helping to protect these valuable natural resources.