The importance of topographic factors on the distribution of bog and heath in a Newfoundland blanket bog complex

Graniero, Phil A.; Price, Jonathan S.

doi:10.1016/s0341-8162(99)00008-9

Cited by 31 publications

(28 citation statements)

References 12 publications

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“…However, these narrow areas are not distributed randomly over the landscape but typically are spatially associated with blanket bog margins where hydraulic gradients within the bog evidently support groundwater inputs to fen. As topography was found to explain statistically about 22% of the present distribution of bog in this landscape (Graniero and Price, 1999b), both pedogenic factors and upslope water inputs from bog must be significant paludification mechanisms (Lapen and Wang, 1999).…”

Section: Role Of Recharge To the Water Tablementioning

confidence: 84%

Modelling two‐dimensional steady‐state groundwater flow and flow sensitivity to boundary conditions in blanket peat complexes

Lapen

Price

Gilbert

2004

Hydrological Processes

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Abstract:This study used a two-dimensional steady-state finite-element groundwater flow model to simulate groundwater flow in two Newfoundland blanket peat complexes and to examine flow system sensitivity to changes in water table recharge and aquifer properties. The modelling results were examined within the context of peat-forming processes in the two complexes. Modelled flow compared favourably with observed flow. The sensitivity analyses suggested that more highly decomposed bog peat along bog margins probably has/had a positive impact on net peat accumulation within bog interiors. Peat with lower hydraulic conductivity along bog margins effectively impedes lateral drainage, localizes water table drawdown to extreme bog margins, and elevates water tables along bog interiors. Peat formation and elevated water tables in adjacent poor fens/laggs currently rely on placic and ortstein horizons impeding vertical drainage and water flow inputs from adjacent bogs. Modest reductions in atmospheric recharge were found to govern bog-flowsystem geometries in a way that would adversely affect paludification processes in adjacent fens/laggs.

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Section: Role Of Recharge To the Water Tablementioning

confidence: 84%

Modelling two‐dimensional steady‐state groundwater flow and flow sensitivity to boundary conditions in blanket peat complexes

Lapen

Price

Gilbert

2004

Hydrological Processes

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“…Peatlands generally occur in flat areas that are poorly drained and/or receive runoff and subsurface water from the surrounding landscape (Graniero and Price, 1999). The low permeability catotelm peat layer is permanently saturated.…”

Section: Peat-specific Soils Hydraulicsmentioning

confidence: 99%

ORCHIDEE-PEAT (revision 4596), a model for northern peatland CO<sub>2</sub>, water, and energy fluxes on daily to annual scales

et al. 2018

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Abstract. Peatlands store substantial amounts of carbon and are vulnerable to climate change. We present a modified version of the Organising Carbon and Hydrology In Dynamic Ecosystems (ORCHIDEE) land surface model for simulating the hydrology, surface energy, and CO 2 fluxes of peatlands on daily to annual timescales. The model includes a separate soil tile in each 0.5 • grid cell, defined from a global peatland map and identified with peat-specific soil hydraulic properties. Runoff from non-peat vegetation within a grid cell containing a fraction of peat is routed to this peat soil tile, which maintains shallow water tables. The water table position separates oxic from anoxic decomposition. The model was evaluated against eddy-covariance (EC) observations from 30 northern peatland sites, with the maximum rate of carboxylation (V cmax ) being optimized at each site. Regarding short-term day-to-day variations, the model performance was good for gross primary production (GPP) (r 2 = 0.76; NashSutcliffe modeling efficiency, MEF = 0.76) and ecosystem respiration (ER, r 2 = 0.78, MEF = 0.75), with lesser accuracy for latent heat fluxes (LE, r 2 = 0.42, MEF = 0.14) and and net ecosystem CO 2 exchange (NEE, r 2 = 0.38, MEF = 0.26). Seasonal variations in GPP, ER, NEE, and energy fluxes on monthly scales showed moderate to high r 2 values (0.57-0.86). For spatial across-site gradients of annual mean GPP, ER, NEE, and LE, r 2 values of 0.93, 0.89, 0.27, and 0.71 were achieved, respectively. Water table (WT) variation was not well predicted (r 2 < 0.1), likely due to the uncertain water input to the peat from surrounding areas. However, the poor performance of WT simulation did not greatly affect predictions of ER and NEE. We found a significant relationship between optimized V cmax and latitude (temperature), which better reflects the spatial gradients of annual NEE than using an average V cmax value.

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“…Heathland biodiversity has been studied extensively in many parts of the world, mainly in Europe (Roem and Berendse 2000;Canals and Sebastia 2002;Gallet and Roze 2002; and eastern North America (Mallik 1995;Dunwiddie et al 1996;Foster and Motzkin 2003;Graniero and Price 1999;Motzkin and Foster 2002;Latham 2003;Lorimer and White 2003). Although not universally similar in their floristic, abiotic or successional characteristics, heathland systems are typically acidic, nutrient-poor habitat types dominated by ericaceous vegetation (Webb 1998;Schmidt et al 2004;).…”

Section: Introductionmentioning

confidence: 99%

Species richness, abundance, rarity and environmental gradients in coastal barren vegetation

Oberndorfer

Lundholm

2008

Biodivers Conserv

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Coastal barrens in Nova Scotia are heathlands characterised by short, predominantly ericaceous vegetation, sparse tree cover, exposed bedrock, pockets of Sphagnum bog, and stressful climatic conditions. Although coastal barrens are prominent in the physical and cultural landscape, they are largely unprotected. We selected six barrens along the Atlantic coast, and surveyed 20 1-m 2 plots at each barren for vascular plants, macrolichens, mosses and environmental factors. We recorded 173 species (105 vascular, 41 macrolichen, 27 moss), including six provincially rare vascular species found predominantly in nearshore areas with high levels of substrate salt and nutrients, variable substrate depth, and short vegetation. Although vascular plant and moss richness were similarly correlated with vegetation height, substrate depth, organic matter content, and rock exposure, there were no clear correlations between vascular plant, macrolichen and moss richness across all sites. Vascular plant rarity and species richness were not correlated, but had inverse relationships with key environmental gradients. Tailoring conservation efforts to protect areas of high richness may thus mean that rare species are missed, and vice versa. Ordination and ANOSIM show that barrens vegetation differs widely among sites; therefore, protecting any singular coastal barren will not protect the entire range of vegetation communities and species in this heathland type. Conservation planning should emphasize protecting environmental gradients correlated with richness, rarity and plant community structure, including substrate depth and moisture, and vegetation height. Additionally, protected areas should include a coastal-inland gradient and a diversity of substrate types, including exposed rock and trees.

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The importance of topographic factors on the distribution of bog and heath in a Newfoundland blanket bog complex

Cited by 31 publications

References 12 publications

Modelling two‐dimensional steady‐state groundwater flow and flow sensitivity to boundary conditions in blanket peat complexes

Modelling two‐dimensional steady‐state groundwater flow and flow sensitivity to boundary conditions in blanket peat complexes

ORCHIDEE-PEAT (revision 4596), a model for northern peatland CO<sub>2</sub>, water, and energy fluxes on daily to annual scales

Species richness, abundance, rarity and environmental gradients in coastal barren vegetation

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The importance of topographic factors on the distribution of bog and heath in a Newfoundland blanket bog complex

Cited by 31 publications

References 12 publications

Modelling two‐dimensional steady‐state groundwater flow and flow sensitivity to boundary conditions in blanket peat complexes

Modelling two‐dimensional steady‐state groundwater flow and flow sensitivity to boundary conditions in blanket peat complexes

ORCHIDEE-PEAT (revision 4596), a model for northern peatland CO&lt;sub&gt;2&lt;/sub&gt;, water, and energy fluxes on daily to annual scales

Species richness, abundance, rarity and environmental gradients in coastal barren vegetation

Contact Info

Product

Resources

About

ORCHIDEE-PEAT (revision 4596), a model for northern peatland CO<sub>2</sub>, water, and energy fluxes on daily to annual scales