Developing land use strategies in landscapes with changing priority, the case of peatland management

Globally, peatlands experience water storage fluctuations. Seasonality was once the sole contributor of this natural water table variation, however, for many years, freshwater drainage of peatlands for agriculture, afforestation, and energy production has been prevalent. With constant changes in storage, there exists a measurable connection between subsurface water levels and solute transport in the deep layers of peatland material. Traditionally, water level modelling has benefitted environmental protection schemes with the identification of critically important areas and by implementing relevant hydraulic structures for optimal protection. Restoration and rehabilitation efforts occurring in the last several decades have occasionally highlighted results of miscalculation, whereby a peatland’s capacity to alleviate water flux effects was overestimated in degraded regions. Once a peat layer becomes dry and aerated, it decomposes, releasing nitrogen and other nutrients into the environment. Conversely, if a peatland is inundated beyond its storage capacity, aggregates of peat and vegetation become suspended within the excess water, signifying the potential for an increased methane flux.

In spite of an ideal water level, one that satisfies a degraded condition while preventing excess flooding, research must continue to expand upon land use and management activities and how they affect hydrology and water quality parameters across a given peatland. To quantify geochemical and hydrological properties given the scale of highly variable peat parameters, many studies have relied on single point data to represent peatlands. Since water chemistry has a strong control on geophysics in peatland environments, a remote sensing technique was used in this study to qualitatively describe the surface of a cutaway peatland. Qualitative analysis of the study site describes soil moisture and peat depth through a geophysical interpretation and an ability to detect gamma radiation.

Remote sensing data, acquired by the Geological Survey Ireland, was used to capture radiometric variation at the study site. The airborne survey data was used to identify suitable locations on the study site in which to collect representative soil cores, which were then brought to the laboratory for analysis. The results from laboratory-based hydrological testing of these cores will be used to quantify the impacts of various water management regimes on site. By combining geophysical analysis with laboratory measurements of soil and water chemistry, there is an opportunity for improving upon the development of suitable mitigation measures.