Including methane emissions from agricultural ponds in national greenhouse gas inventories

Authors

Martino E. Malerba, Deakin University, AustraliaFollow
Tertius de Kluyver, Australian Department of Climate Change, Australian Capital Territory
Nicholas J. Wright, Department of Primary Industries and Regional Development, Western AustraliaFollow
Odebiri Omosalewa, Deakin University, Australia
Peter I. Macreadie, Deakin University, Australia

Document Type

Article

Publication Date

5-2-2024

Journal Title

Environmental Science and Technology

ISSN

Print: 0013-936X Electronic: 1520-5851

Keywords

farm dams, agricultural ponds, agricultural reservoirs, impoundments, dugouts, eutrophication, inland wetlands, methane ebullition, national inventory reports

Disciplines

Climate | Natural Resources and Conservation | Water Resource Management

Abstract

Agricultural ponds are a significant source of greenhouse gases, contributing to the ongoing challenge of anthropogenic climate change. Nations are encouraged to account for these emissions in their national greenhouse gas inventory reports. We present a remote sensing approach using open-access satellite imagery to estimate total methane emissions from agricultural ponds that account for (1) monthly fluctuations in the surface area of individual ponds, (2) rates of historical accumulation of agricultural ponds, and (3) the temperature dependence of methane emissions. As a case study, we used this method to inform the 2024 National Greenhouse Gas Inventory reports submitted by the Australian government, in compliance with the Paris Agreement. Total annual methane emissions increased by 58% from 1990 (26 kilotons CH4 year–1) to 2022 (41 kilotons CH4 year–1). This increase is linked to the water surface of agricultural ponds growing by 51% between 1990 (115 kilo hectares; 1,150 km2) and 2022 (173 kilo hectares; 1,730 km2). In Australia, 16,000 new agricultural ponds are built annually, expanding methane-emitting water surfaces by 1,230 ha yearly (12.3 km2 year–1). On average, the methane flux of agricultural ponds in Australia is 0.238 t CH4 ha–1 year–1. These results offer policymakers insights into developing targeted mitigation strategies to curb these specific forms of anthropogenic emissions. For instance, financial incentives, such as carbon or biodiversity credits, can mobilize widespread investments toward reducing greenhouse gas emissions and enhancing the ecological and environmental values of agricultural ponds. Our data and modeling tools are available on a free cloud-based platform for other countries to adopt this approach.

Recommended Citation

Malerba, M E, de Kluyver, T, Wright, N J, Omosalewa, O, and Macreadie, P I. (2024), Including methane emissions from agricultural ponds in national greenhouse gas inventories. Environmental Science and Technology, 58 (19), 8349-8359.
https://library.dpird.wa.gov.au/cs_researchart/4