Journal article
Punching above their weight: large release of greenhouse gases from small agricultural dams
Global Change Biology, Vol.25(2), pp.721-732
2019
Metrics
27 Record Views
UN Sustainable Development Goals (SDGs)
This output has contributed to the advancement of the following goals:
Source: InCites
Abstract
<p>Freshwater ecosystems play a major role in global carbon cycling through the breakdown of organic material and release of greenhouse gases (GHGs). Carbon dioxide (CO<sub>2</sub>) and methane (CH<sub>4</sub>) emissions from lakes, wetlands, reservoirs and small natural ponds have been well studied, however, the GHG emissions of highly abundant, small‐scale (<0.01 km<sup>2</sup>) agricultural dams (small stream and run‐off impoundments) are still unknown. Here, we measured the diffusive CO<sub>2</sub> and CH<sub>4</sub> flux of 77 small agricultural dams within south‐east Australia. The GHG emissions from these waterbodies, which are currently unaccounted for in GHG inventories, amounted to 11.12 ± 2.59 g CO<sub>2</sub>‐equivalent m<sup>2</sup>/day, a value 3.43 times higher than temperate reservoir emissions. Upscaling these results to the entire state of Victoria, Australia, resulted in a farm dam CO<sub>2</sub>‐equivalent/day emission rate of 4,853 tons, 3.1 times higher than state‐wide reservoir emissions in spite of farm dams covering only 0.94 times the comparative area. We also show that CO<sub>2</sub> and CH<sub>4</sub> emission rates were both significantly positively correlated with dissolved nitrate concentrations, and significantly higher in livestock rearing farm dams when compared to cropping farm dams. The results from this study demonstrate that small agricultural farm dams can be a major source of greenhouse gas emissions, thereby justifying their inclusion in global carbon budgets.</p>
Details
- Title
- Punching above their weight: large release of greenhouse gases from small agricultural dams
- Creators
- Quinn R Ollivier - Deakin University, AustraliaDamien T Maher - Southern Cross University, AustraliaChris Pitfield - Corangamite Catchment Management Authority, AustraliaPeter I Macreadie - Deakin University, Australia
- Publication Details
- Global Change Biology, Vol.25(2), pp.721-732
- Identifiers
- 4701; 991012821053002368
- Academic Unit
- National Marine Science Centre; School of Environment, Science and Engineering; Faculty of Science and Engineering; Science
- Resource Type
- Journal article