Naomi Gatis

Dr. Naomi Gatis

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Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 September 2015 in Journal of Environmental Management
Verified
Journal Article
Open access
EGE. Grand-Clement
E. Grand-Clement
KAK. Anderson
K. Anderson
DSD. Smith
D. Smith
MAM. Angus
M. Angus
DLDavid Luscombe
David Luscombe
RBR.E. Brazier
R.E. Brazier
Globally, the historic and recent exploitation of peatlands through management practices such as agricultural reclamation, peat harvesting or forestry, have caused extensive damage to these ecosystems. Their value is now increasingly recognised, and restoration and rehabilitation programmes are underway to improve some of the ecosystem services provided by peatlands: blocking drainage ditches in deep peat has been shown to improve the storage of water, decrease carbon losses in the long-term, and improve biodiversity. However, whilst the restoration process has benefitted from experience and technical advice gained from restoration of deep peatlands, shallow peatlands have received less attention in the literature, despite being extensive in both uplands and lowlands. Using the experience gained from the restoration of the shallow peatlands of Exmoor National Park (UK), and two test catchments in particular, this paper provides technical guidance which can be applied to the restoration of other shallow peatlands worldwide. Experience showed that integrating knowledge of the historical environment at the planning stage of restoration was essential, as it enabled the effective mitigation of any threat to archaeological features and sites. The use of bales, commonly employed in other upland ecosystems, was found to be problematic. Instead, 'leaky dams' or wood and peat combination dams were used, which are both more efficient at reducing and diverting the flow, and longer lasting than bale dams. Finally, an average restoration cost (£306 ha(-1)) for Exmoor, below the median national value across the whole of the UK, demonstrates the cost-effectiveness of these techniques. However, local differences in peat depth and ditch characteristics (i.e. length, depth and width) between sites affect both the feasibility and the cost of restoration. Overall, the restoration of shallow peatlands is shown to be technically viable; this paper provides a template for such process over analogous landscapes.

8 May 2022 in People and Nature
Verified
Journal Article
Open access
IBIan Bateman
Ian Bateman
KAKaren Anderson
Karen Anderson
AAArthur Argles
Arthur Argles
CBClaire Belcher
Claire Belcher
RBRichard A. Betts
Richard A. Betts
GXGeorgios Xenakis
Georgios Xenakis
We outline the principles of the natural capital approach to decision making and apply these to the contemporary challenge of very significantly expanding woodlands as contribution to attaining net zero emissions of greenhouse gases. Drawing on the case of the UK, we argue that a single focus upon carbon storage alone is likely to overlook the other ‘net zero plus’ benefits which woodlands can deliver. A review of the literature considers the wide variety of potential benefits which woodlands can provide, together with costs such as foregone alternative land uses. We argue that decision making must consider all of these potential benefits and costs for the right locations to be planted with the right trees. The paper closes by reviewing the decision support systems necessary to incorporate this information into policy and decision making. Read the freePlain Language Summaryfor this article on the Journal blog.

22 September 2023 in Scientific Reports
Verified
Journal Article
Open access
PDF file
NGNaomi Gatis
Naomi Gatis
PBPia Benaud
Pia Benaud
KAKaren Anderson
Karen Anderson
JAJosie Ashe
Josie Ashe
EGEmilie Grand-Clement
Emilie Grand-Clement
RBRichard E. Brazier
Richard E. Brazier
Peatland restoration is experiencing a global upsurge as a tool to protect and provide various ecosystem services. As the range of peatland types being restored diversifies, do previous findings present overly optimistic restoration expectations? In an eroding and restored upland peatland we assessed short-term (0–4 year) effects of restoration on ecohydrological functions. Restoration significantly reduced discharge from the site, transforming peat pans into pools. These retained surface water over half the time and were deeper during wet periods than before. In the surrounding haggs water tables stabilised, as drawdown during dry conditions reduced, increasing the saturated peat thickness. Despite these changes, there were no effects on photosynthesis, ecosystem respiration or dissolved organic carbon loads leaving the site. Soil respiration did not decrease as water tables rose, but methane emissions were higher from rewet pools. Restoration has had a dramatic effect on hydrology, however, consequent changes in other ecosystem functions were not measured in the 4 years after restoration. Whilst restoration is crucial in halting the expansion of degraded peatland areas, it is vital that practitioners and policymakers advocating for restoration are realistic about the expected outcomes and timescales over which these outcomes may manifest.

29 April 2015 in Ecohydrology
Verified
Journal Article
Open access
PDF file
NGNaomi Gatis
Naomi Gatis
DLDavid J. Luscombe
David J. Luscombe
EGEmilie Grand‐Clement
Emilie Grand‐Clement
IHIain P. Hartley
Iain P. Hartley
KAKaren Anderson
Karen Anderson
RBRichard E. Brazier
Richard E. Brazier
Peatlands are recognized as important carbon stores; despite this, many have been drained for agricultural improvement. Drainage has been shown to lower water tables and alter vegetation composition, modifying primary productivity and decomposition, potentially initiating peat loss. To quantify CO2 fluxes across whole landscapes, it is vital to understand how vegetation composition and CO2 fluxes vary spatially in response to the pattern of drainage features. However, Molinia caerulea-dominated peatlands are poorly understood despite their widespread extent. Photosynthesis (PG600) and ecosystem respiration (REco) were modelled (12 °C, 600 µmol photons m−2 s−1, greenness excess index of 60) using empirically derived parameters based on closed-chamber measurements collected over a growing season. Partitioned below-ground fluxes were also collected. Plots were arranged ⅛, ¼ and ½ the distance between adjacent ditches in two catchments located in Exmoor National Park, southwest England. Water table depths were deepest closest to the ditch and non-significantly (p = 0·197) shallower further away. Non-Molinia species coverage and the Simpson diversity index significantly decreased with water table depth (p < 0·024) and increased non-significantly (p < 0·083) away from the ditch. No CO2 fluxes showed significant spatial distribution in response to drainage ditches, arguably due to insignificant spatial distribution of water tables and vegetation composition. Whilst REco showed no significant spatial variation, PG600 varied significantly between sites (p = 0·012), thereby controlling the spatial distribution of net ecosystem exchange between sites. As PG600 significantly co-varied with water table depths (p = 0·034), determining the spatial distribution of water table depths may enable CO2 fluxes to be estimated across M. caerulea-dominated landscapes. © 2015 The Authors. Ecohydrology published by John Wiley & Sons, Ltd.

22 July 2022 in Ecological Solutions and Evidence
Verified
Journal Article
Open access
NGNaomi Gatis
Naomi Gatis
DCDonna Carless
Donna Carless
DLDavid J. Luscombe
David J. Luscombe
RBRichard E. Brazier
Richard E. Brazier
KAKaren Anderson
Karen Anderson
Accurate and up‐to‐date land cover maps are vital for underpinning evidence‐based landscape management decision‐making. However, the technical skills required to extract tailored information about land cover dynamics from these open‐access geospatial data often limit their use by those making landscape management decisions. Using Dartmoor National Park as an example, we demonstrate an open‐source toolkit which uses open‐source software (QGIS and RStudio) to process freely available Sentinel‐2 and public LiDAR data sets to produce fine scale (10 m2 grain size) land cover maps. The toolbox has been designed for use by staff within the national park, for example, enabling land cover maps to be updated as required in the future. An area of 945 km2 was mapped using a trained random forest classifier following a classification scheme tailored to the needs of the national park. A 2019 land cover map had an overall user's accuracy of 79%, with 13 out of 17 land cover classes achieving greater than 70% accuracy. Spatially, accuracy was related via logistical regression to blue band surface reflectance in the spring and topographic slope derived from LiDAR (1 m resolution), with greater accuracy in steeper terrain and areas exhibiting higher blue reflectance. Between an earlier (2017–2019) and later (2019–2021) time frame, 8% of pixels changed, most of the change by area occurred in the most common classes. However, the largest proportional increase occurred in Upland Meadows, Lowland Meadows and Blanket Bog, all habitats subject to restoration efforts. Identifying areas of change enables future field work to be better targeted. We discuss the application of this mapping to land management within the Dartmoor national park and of the potential of tailored land cover and land cover change mapping, via this toolbox, to evidence‐based environmental decision‐making more widely.

23 February 2019 in Wetlands Ecology and Management
Verified
Journal Article
Open access
PDF file
NGNaomi Gatis
Naomi Gatis
PBPia Benaud
Pia Benaud
JAJosie Ashe
Josie Ashe
DLDavid Luscombe
David Luscombe
EGEmilie Grand-Clement
Emilie Grand-Clement
RBRichard E. Brazier
Richard E. Brazier
Peatlands are recognised as an important but vulnerable ecological resource. Understanding the effects of existing damage, in this case erosion, enables more informed land management decisions to be made. Over the growing seasons of 2013 and 2014 photosynthesis and ecosystem respiration were measured using closed chamber techniques within vegetated haggs and erosional peat pans in Dartmoor National Park, southwest England. Below-ground total and heterotrophic respiration were measured and autotrophic respiration estimated from the vegetated haggs. The mean water table was significantly higher in the peat pans than in the vegetated haggs; because of this, and the switching from submerged to dry peat, there were differences in vegetation composition, photosynthesis and ecosystem respiration. In the peat pans photosynthetic CO2 uptake and ecosystem respiration were greater than in the vegetated haggs and strongly dependent on the depth to water table (r2 > 0.78, p < 0.001). Whilst in the vegetated haggs, photosynthesis and ecosystem respiration had the strongest relationships with normalised difference vegetation index (NDVI) (r2 = 0.82, p < 0.001) and soil temperature at 15 cm depth (r2 = 0.77, p = 0.001). Autotrophic and total below-ground respiration in the vegetated haggs varied with soil temperature; heterotrophic respiration increased as water tables fell. An empirically derived net ecosystem model estimated that over the two growing seasons both the vegetated haggs (29 and 20 gC m−2; 95% confidence intervals of − 570 to 762 and − 873 to 1105 gC m−2) and the peat pans (7 and 8 gC m−2; 95% confidence intervals of − 147 to 465 and − 136 to 436 gC m−2) were most likely net CO2 sources. This study suggests that not only the visibly degraded bare peat pans but also the surrounding vegetated haggs are losing carbon to the atmosphere, particularly during warmer and drier conditions, highlighting a need for ecohydrological restoration.