scholarly journals The impact of ditch blocking on fluvial carbon export from a UK blanket bog

2018 ◽  
Vol 32 (13) ◽  
pp. 2141-2154 ◽  
Author(s):  
Christopher D. Evans ◽  
Michael Peacock ◽  
Sophie M. Green ◽  
Joseph Holden ◽  
Pippa J. Chapman ◽  
...  
Keyword(s):  
Carbon Export ◽  
Blanket Bog ◽  
Ditch Blocking ◽  
The Impact

Ditch blocking, water chemistry and organic carbon flux: Evidence that blanket bog restoration reduces erosion and fluvial carbon loss

2011 ◽  
Vol 409 (11) ◽  
pp. 2010-2018 ◽  
Author(s):  
Lorraine Wilson ◽  
Jared Wilson ◽  
Joseph Holden ◽  
Ian Johnstone ◽  
Alona Armstrong ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Water Chemistry ◽  
Carbon Flux ◽  
Carbon Loss ◽  
Organic Carbon Flux ◽  
Blanket Bog ◽  
Ditch Blocking

Short-term impact of sheep and cattle grazing on upland wet heath vegetation

2005 ◽  
Vol 2005 ◽  
pp. 230-230
Author(s):  
C. N. R. Critchley ◽  
H. F. Adamson ◽  
J. J. Hyslop
Keyword(s):  
Action Plan ◽  
Plant Species Composition ◽  
Short Term ◽  
Environmentally Sustainable ◽  
Heavy Grazing ◽  
Blanket Bog ◽  
Grazing Systems ◽  
The Uk ◽  
The Impact ◽  
Cattle And Sheep

The UK Biodiversity Action Plan identifies upland heath and blanket bog as priorities for conservation. Heavy grazing by livestock has damaged these habitats in many parts of the UK. Agri-environment schemes have partly addressed the problem by encouraging farmers to reduce sheep stocking levels on degraded moorland. This can prevent further loss of dwarf shrub cover, but the increased biomass of moorland grasses can inhibit regeneration of dwarf shrubs and other desirable species. The objectives of this system-scale study are to assess the impact on plant species composition and animal performance, of sheep-only and mixed grazing regimes with both cattle and sheep on degraded wet heath vegetation. It is being carried out as part of a wider project to determine environmentally sustainable and economically viable grazing systems for heather moorland.

Air—sea C0 2 transfer and the carbon budget of the North Atlantic

1995 ◽  
Vol 348 (1324) ◽  
pp. 211-219 ◽  
Keyword(s):  
Spatial Distribution ◽  
Carbon Budget ◽  
Dissolved Inorganic Carbon ◽  
Model Simulation ◽  
Bering Strait ◽  
Carbon Export ◽  
The North ◽  
The Pacific ◽  
Ocean Carbon ◽  
The Impact

A model simulation of the global carbon cycle demonstrates that the biological and solubility pumps are of comparable importance in determining the spatial distribution of annual mean air-sea fluxes in the Atlantic. The model also confirms that the impact of the (steady state) biological pump on the magnitude and spatial distribution of anthropogenic CO 2 uptake is minimal. An Atlantic Ocean carbon budget developed from analysis of the model combined with observations suggests that the air-sea flux of carbon is inadequate to supply the postulated large dissolved inorganic carbon export from the Atlantic. Other sources of carbon are required, such as an input from the Pacific via the Bering Strait and Arctic, river inflow, or an import of dissolved organic carbon.

scholarly journals Anomalous Reduction of the Total Suspended Matter During the COVID-19 Lockdown in the Hooghly Estuarine System

2021 ◽  
Vol 8 ◽  
Author(s):  
Chiranjivi Jayaram ◽  
Rajdeep Roy ◽  
Neethu Chacko ◽  
Debadatta Swain ◽  
Ramunaidu Punnana ◽  
...  
Keyword(s):  
Suspended Matter ◽  
Anthropogenic Activities ◽  
Positive Influence ◽  
Total Suspended Matter ◽  
Landsat 8 ◽  
Estuarine System ◽  
Carbon Export ◽  
Sediment Removal ◽  
Brick Kilns ◽  
The Impact

The impact of the coronavirus disease 2019 (COVID-19) lockdown in the Hooghly estuarine region, India is assessed using the total suspended matter (TSM) concentration. The estimation of TSM is performed using Landsat-8/operational land imager (OLI), and an intercomparison of TSM load during the pre-lockdown and lockdown periods is done. It is observed that during the lockdown period, TSM reduced by 30–50%. This is a significant observation considering the ecological balance of the region and the fact that it is home to the largest mangroves in the world. This change in suspended matter presumably reflects the influence of reduction in anthropogenic activities owing to the COVID-19 lockdowns, such as industries, closure of shipping activities (through less dredging), and brick kilns (through less sediment removal), which are generally the primary contributors in this region. Even though these observed changes are representative of the positive influence of the COVID-19 lockdown, its implications in estuarine biogeochemistry still remain poorly quantified. The decrease in TSM content may increase light penetration, thereby increasing the primary productivity. In addition, low sediment load reaching the Bay of Bengal could influence the carbon export due to reduction in ballasting effect as reported from this region. In summary, the influence of the COVID-19 lockdown on the biogeochemistry of the aquatic ecosystem appears rather complex than thought earlier and may vary regionally based on local hydrodynamics. The analysis elucidates the complex interplay of regional lockdown and its implication in modulation of local biogeochemistry. However, the relative importance of each process in the Hooghly estuary remains to be fully evaluated.

scholarly journals Marine Phytoplankton Stoichiometry Mediates Nonlinear Interactions Between Nutrient Supply, Temperature, and Atmospheric CO<sub>2</sub>

2017 ◽  
Author(s):  
Allison R. Moreno ◽  
George I. Hagstrom ◽  
Francois W. Primeau ◽  
Simon A. Levin ◽  
Adam C. Martiny
Keyword(s):  
Carbon Cycling ◽  
Ocean Circulation ◽  
Negative Relationship ◽  
Nutrient Supply ◽  
Marine Phytoplankton ◽  
Phosphorus Concentration ◽  
Biological Pump ◽  
Carbon Export ◽  
Environmental Model ◽  
The Impact

Abstract. Marine phytoplankton stoichiometry links nutrient supply to marine carbon export. Deviations of phytoplankton stoichiometry from Redfield proportions (106C : 1P) could therefore have a significant impact on carbon cycling, and understanding which environmental factors drive these deviations may reveal new mechanisms that regulate the carbon cycle. To explore the links between environmental conditions, stoichiometry, and carbon cycling, we compared four different models for variations in phytoplankton C : P: a fixed Redfield model, a model with C : P given as a function of surface phosphorus concentration ([P]), a model with C : P given as a function of temperature, and a new multi-environmental model that predicts C : P as a function of light, temperature, and [P]. These stoichiometric models were embedded into a box model of the ocean circulation, which resolves the three major ocean biomes (high-latitude, subtropical gyres, and iron-limited tropical upwelling regions). Contrary to the expectation of a monotonic relationship between surface nutrient drawdown and carbon export, we found that lateral nutrient transport from lower C : P tropical waters to high C : P subtropical waters could cause carbon-export to decrease with increased tropical nutrient utilization. Temperature is thought to be one of the primary drivers of changes in atmospheric pCO2 (pCO2,atm) across glacial/interglacial periods, and it has been hypothesized that a positive feedback between temperature and pCO2,atm will play an important role in anthropogenic climate change, with changes in the biological pump playing at most a secondary role. Here we show that environmentally driven shifts in stoichiometry make the biological pump more influential, and may reverse the expected negative relationship between temperature and pCO2,atm. In the temperature-only model changes in tropical temperature have more impact on the Δ pCO2,atm (~ 41 ppm) compared to subtropical temperature (~ 4.5 ppm). Our multi-environmental model produced a decline in pCO2,atm of ~ 46 when temperature spanned a change of 10 °C. Thus, we find that variation in marine phytoplankton stoichiometry and its environmental controlling factor can lead to counterintuitive controls on pCO2,atm, suggesting the need for further studies of ocean C : P and the impact on ocean carbon cycling.

Ecological Impact of Plantation Forestry on Blanket Bog on a Low Order Stream

2021 ◽  
Author(s):  
Raymond Flynn ◽  
Cormac McConigley ◽  
Gary O'Connell ◽  
Francis Mackin ◽  
Florence Renou Wilson
Keyword(s):  
Ecological Impact ◽  
Base Flow ◽  
Plantation Forestry ◽  
Sampling Point ◽  
High Status ◽  
Study Results ◽  
Blanket Bog ◽  
The Impact ◽  
Runoff Quality ◽  
Low Order

&lt;p&gt;Blanket peat directly underlies between 11% and 13% of Ireland, with catchments containing more than 10% blanket bog coverage hosting the majority of Water Framework Directive High Status sites. Since 1998 approximately 40% of these sites have experienced a decline in status, with catchments having peat coverage greater than 40% experiencing disproportionate impacts. Declines in status have typically been accompanied by anthropogenic activities that have affected bog hydrology; these include planting / maturing of plantation forestry on deep peat (&gt; 1 metre thick). Although our understanding of mechanisms driving aquatic ecosystem degradation in these areas immediately after planting and following felling has improved considerably in recent years, the impact of mature closed canopy forestry on runoff remains less well defined. Moreover, where research has been carried out, it has focused on sampling conditions during high (quick) flow, while base flow conditions have received less attention.&lt;/p&gt;&lt;p&gt;Comparison of runoff quality, in a stream draining a relatively intact blanket bog-covered catchment, with conditions further downstream, after it had flowed through a mature Sitka Spruce (P.sitchesnsis) plantation on deep peat, aimed to better characterise the impact of the forestry on the stream&amp;#8217;s ecology. The study area selected for investigation receives approximately 1600 mm/yr of precipitation, occurring throughout the year (259 days with &gt;0.2mm precipitation). Pairwise comparisons of runoff quality between areas draining open bog land and afforested areas further downstream failed to detect significant differences during high flow events. By contrast samples collected under drier conditions proved significantly more mineralised downstream, with water containing significantly higher levels of Calcium and Magnesium at the afforested area sampling point. Similarly, visual observations in forest drains feeding the stream revealed the presence of tufa mounds, which had developed following planting, and zones of focused iron oxyhydroxide-bearing groundwater upwelling; these features proved absent upstream of the forestry.&lt;/p&gt;&lt;p&gt;Screening for biotic status at the outlets of blanket bog and forested catchments, using the Irish biological quality rating system (Q-scores), suggested that the upstream sampling point was indicative of Good status (Q4), whilst the findings at the downstream forested site were more indicative of High status (Q4-5).&amp;#160; &amp;#160;However, more detailed analysis of the species sampled suggested that although the sampling point in the forested area (downstream monitoring point) had higher biodiversity and as such allowed for the improvement in Q-score, it had slightly lower species density through lower counts of certain species. This is consistent with findings elsewhere which have highlighted the capacity of aqueous iron oxyhydroxides to detrimentally impact sensitive species, such as freshwater pearl mussel (M. margaritifera). Study results provide further evidence of the capacity of plantation forestry to impact on the aquatic ecology of low order streams, while further highlighting the need for alternative ecological metrics when investigating the impacts from human activity on lower order streams draining blanket bog.&lt;/p&gt;

scholarly journals The impact of drain blocking on an upland blanket bog during storm and drought events, and the importance of sampling-scale

2011 ◽  
Vol 404 (3-4) ◽  
pp. 198-208 ◽  
Author(s):  
Lorraine Wilson ◽  
Jared Wilson ◽  
Joseph Holden ◽  
Ian Johnstone ◽  
Alona Armstrong ◽  
...  
Keyword(s):  
Blanket Bog ◽  
Sampling Scale ◽  
The Impact

scholarly journals The impact of ditch blocking on the hydrological functioning of blanket peatlands

2016 ◽  
Vol 31 (3) ◽  
pp. 525-539 ◽  
Author(s):  
Joseph Holden ◽  
Sophie M. Green ◽  
Andy J. Baird ◽  
Richard P. Grayson ◽  
Gemma P. Dooling ◽  
...  
Keyword(s):  
Ditch Blocking ◽  
The Impact ◽  
Blanket Peatlands ◽  
Hydrological Functioning

scholarly journals Carbon export in the naturally iron-fertilized Kerguelen area of the Southern Ocean based on the <sup>234</sup>Th approach

2015 ◽  
Vol 12 (12) ◽  
pp. 3831-3848 ◽  
Author(s):  
F. Planchon ◽  
D. Ballas ◽  
A.-J. Cavagna ◽  
A. R. Bowie ◽  
D. Davies ◽  
...  
Keyword(s):  
Carbon Flux ◽  
Reference Station ◽  
Kerguelen Plateau ◽  
Carbon Export ◽  
Central Plateau ◽  
Austral Spring ◽  
Export Production ◽  
Sinking Particles ◽  
Poc Export ◽  
The Impact

Abstract. This study examined upper-ocean particulate organic carbon (POC) export using the 234Th approach as part of the second KErguelen Ocean and Plateau compared Study expedition (KEOPS2). Our aim was to characterize the spatial and the temporal variability of POC export during austral spring (October–November 2011) in the Fe-fertilized area of the Kerguelen Plateau region. POC export fluxes were estimated at high productivity sites over and downstream of the plateau and compared to a high-nutrient low-chlorophyll (HNLC) area upstream of the plateau in order to assess the impact of iron-induced productivity on the vertical export of carbon. Deficits in 234Th activities were observed at all stations in surface waters, indicating early scavenging by particles in austral spring. 234Th export was lowest at the reference station R-2 and highest in the recirculation region (E stations) where a pseudo-Lagrangian survey was conducted. In comparison 234Th export over the central plateau and north of the polar front (PF) was relatively limited throughout the survey. However, the 234Th results support that Fe fertilization increased particle export in all iron-fertilized waters. The impact was greatest in the recirculation feature (3–4 fold at 200 m depth, relative to the reference station), but more moderate over the central Kerguelen Plateau and in the northern plume of the Kerguelen bloom (~2-fold at 200 m depth). The C : Th ratio of large (>53 μm) potentially sinking particles collected via sequential filtration using in situ pumping (ISP) systems was used to convert the 234Th flux into a POC export flux. The C : Th ratios of sinking particles were highly variable (3.1 ± 0.1 to 10.5 ± 0.2 μmol dpm−1) with no clear site-related trend, despite the variety of ecosystem responses in the fertilized regions. C : Th ratios showed a decreasing trend between 100 and 200 m depth suggesting preferential carbon loss relative to 234Th possibly due to heterotrophic degradation and/or grazing activity. C : Th ratios of sinking particles sampled with drifting sediment traps in most cases showed very good agreement with ratios for particles collected via ISP deployments (>53 μm particles). Carbon export production varied between 3.5 ± 0.9 and 11.8 ± 1.3 mmol m−2 d−1 from the upper 100 m and between 1.8 ± 0.9 and 8.2 ± 0.9 mmol m−2 d−1 from the upper 200 m. The highest export production was found inside the PF meander with a range of 5.3 ± 1.0 to 11.8 ± 1.1 mmol m−2 d−1 over the 19-day survey period. The impact of Fe fertilization is highest inside the PF meander with 2.9–4.5-fold higher carbon flux at 200 m depth in comparison to the HNLC control station. The impact of Fe fertilization was significantly less over the central plateau (stations A3 and E-4W) and in the northern branch of the bloom (station F-L) with 1.6–2.0-fold higher carbon flux compared to the reference station R. Export efficiencies (ratio of export to primary production and ratio of export to new production) were particularly variable with relatively high values in the recirculation feature (6 to 27 %, respectively) and low values (1 to 5 %, respectively) over the central plateau (station A3) and north of the PF (station F-L), indicating spring biomass accumulation. Comparison with KEOPS1 results indicated that carbon export production is much lower during the onset of the bloom in austral spring than during the peak and declining phases in late summer.

scholarly journals Marine phytoplankton stoichiometry mediates nonlinear interactions between nutrient supply, temperature, and atmospheric CO<sub>2</sub>

2018 ◽  
Vol 15 (9) ◽  
pp. 2761-2779 ◽  
Author(s):  
Allison R. Moreno ◽  
George I. Hagstrom ◽  
Francois W. Primeau ◽  
Simon A. Levin ◽  
Adam C. Martiny
Keyword(s):  
Carbon Cycling ◽  
Ocean Circulation ◽  
Circulation Model ◽  
Nutrient Supply ◽  
Marine Phytoplankton ◽  
Phosphorus Concentration ◽  
Biological Pump ◽  
Carbon Export ◽  
Environmental Model ◽  
The Impact

Abstract. Marine phytoplankton stoichiometry links nutrient supply to marine carbon export. Deviations of phytoplankton stoichiometry from Redfield proportions (106C : 1P) could therefore have a significant impact on carbon cycling, and understanding which environmental factors drive these deviations may reveal new mechanisms regulating the carbon cycle. To explore the links between environmental conditions, stoichiometry, and carbon cycling, we compared four different models of phytoplankton C : P: a fixed Redfield model, a model with C : P given as a function of surface phosphorus concentration (P), a model with C   P given as a function of temperature, and a new multi-environmental model that predicts C : P as a function of light, temperature, and P. These stoichiometric models were embedded into a five-box ocean circulation model, which resolves the three major ocean biomes (high-latitude, subtropical gyres, and tropical upwelling regions). Contrary to the expectation of a monotonic relationship between surface nutrient drawdown and carbon export, we found that lateral nutrient transport from lower C : P tropical waters to high C : P subtropical waters could cause carbon export to decrease with increased tropical nutrient utilization. It has been hypothesized that a positive feedback between temperature and pCO2, atm will play an important role in anthropogenic climate change, with changes in the biological pump playing at most a secondary role. Here we show that environmentally driven shifts in stoichiometry make the biological pump more influential, and may reverse the expected positive relationship between temperature and pCO2, atm. In the temperature-only model, changes in tropical temperature have more impact on the Δ pCO2, atm (∼ 41 ppm) compared to subtropical temperature changes (∼ 4.5 ppm). Our multi-environmental model predicted a decline in pCO2, atm of ∼ 46 ppm when temperature spanned a change of 10 °C. Thus, we find that variation in marine phytoplankton stoichiometry and its environmental controlling factors can lead to nonlinear controls on pCO2, atm, suggesting the need for further studies of ocean C : P and the impact on ocean carbon cycling.

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