scholarly journals Spatial and temporal dynamics of nitrogen exchange in an upwelling reach of a groundwater‐fed river and potential response to perturbations changing rainfall patterns under UK climate change scenarios

2021 ◽  
Vol 35 (4) ◽  
Author(s):  
Ann Louise Heathwaite ◽  
Catherine Heppell ◽  
Andrew Binley ◽  
Patrick Byrne ◽  
Katrina Lansdown ◽  
...  
Author(s):  
Andrea Fenocchi ◽  
Michela Rogora ◽  
Aldo Marchetto ◽  
Stefano Sibilla ◽  
Claudia Dresti

Climate warming affects lake ecosystems both through its direct effect on the phenology of species and through the alteration of the physical and chemical environments, which in turn affect community composition. In deep lakes, stratification enhancement and mixing reduction have already been observed, leading to hypolimnetic anoxia and to the rise of cyanophytes. The increase in stability depends on the rise of air temperature due to global emissions of greenhouse gases (GHG). Primary production could then either increase with rising epilimnetic temperature and buoyancy or decrease as fewer nutrients are upwelled from deep layers. The prevailing outcome, as well as the quantitative and temporal dynamics of all climate-induced modifications, depend on the specific lake characteristics. Individual analyses are then needed, one-dimensional coupled hydrodynamic-ecological numerical models being suitable tools for such predictions. Here, we simulated with GLM-AED2 (General Lake Model – Aquatic EcoDynamics) the 2020-2085 dynamics of the oligomictic and oligotrophic deep subalpine Lake Maggiore (Italy/Switzerland), according to the Swiss Climate Change Scenarios CH2011. Multiple realisations were performed for each scenario with random meteorological series obtained from the Vector-Autoregressive Weather Generator (VG), highlighting the uncertainties related to meteorology. Increase and decrease of nutrient loads were also tested. Results show that anoxia would occur in the hypolimnion regardless of nutrient input reduction, unless global GHG emissions were immediately reduced. Total phytoplankton biomass would be weakly affected by climate change, strongly depending on nutrient input, yet water warming would cause cyanophytes to compete with diatoms. Therefore, the fate of Lake Maggiore would be tied to both global and local environmental policies.


Author(s):  
Janelle Knox-Hayes

Carbon markets open several important avenues of inquiry into resource governance designed to address problems like climate change. The discipline of economic geography is well situated to add insight. This chapter examines the underlying assumptions behind market-based governance, particularly the emphasis on controlling greenhouse gases through pricing. The pricing of externalities alone does not guarantee the material changes in energy use now in the future that are required to combat climate change. A new framework for consideration of the spatial and temporal dynamics of value is proposed. A renewed focus on use value and its spatial characteristics could lend considerable insight to the understanding of industry, market creation, and resource governance. For example, entraining the temporal production of instruments of exchange to their sources of production and creating property rights to manage natural resources as service stocks rather than commodities could better generate external value.


BMC Ecology ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Belinda J. Vause ◽  
Simon A. Morley ◽  
Vera G. Fonseca ◽  
Anna Jażdżewska ◽  
Gail V. Ashton ◽  
...  

2020 ◽  
Author(s):  
Roopam Shukla ◽  
Amsalu Woldie Yalew ◽  
Stephanie Gleixner ◽  
Bernhard Schauberger ◽  
Christoph Gornott

<p>Vulnerability to climate change differs spatially within the country owing to regional differences in exposure, sensitivity, and adaptive capacity. The paper aims to assess the vulnerability of smallholder farming systems in Ethiopia to observed climate change, to gain insight into factors that may shape vulnerability in the future. Spatial dynamics in vulnerability is assessed at subnational level (zone-level) and temporal dynamics is studied across three time periods i.e. historical (1985-2005), current (2005-2015), and future (2035-2045). The study uses an index-based approach, which is suitable for assessing vulnerability as it includes both biophysical and socio-economic dimensions. This approach combines the environmental and socio-economic data from different sources (agricultural surveys, climate, and remote sensing data) to capture the multi-dimensional attributes of vulnerability. This research contributes to evidence-based adaptation planning in Ethiopia by identifying areas and patterns of high vulnerability and its components.</p>


2011 ◽  
Author(s):  
M. Leonard ◽  
N. Ferjan Ramirez ◽  
C. Torres ◽  
M. Hatrak ◽  
R. Mayberry ◽  
...  

2020 ◽  
Vol 637 ◽  
pp. 117-140 ◽  
Author(s):  
DW McGowan ◽  
ED Goldstein ◽  
ML Arimitsu ◽  
AL Deary ◽  
O Ormseth ◽  
...  

Pacific capelin Mallotus catervarius are planktivorous small pelagic fish that serve an intermediate trophic role in marine food webs. Due to the lack of a directed fishery or monitoring of capelin in the Northeast Pacific, limited information is available on their distribution and abundance, and how spatio-temporal fluctuations in capelin density affect their availability as prey. To provide information on life history, spatial patterns, and population dynamics of capelin in the Gulf of Alaska (GOA), we modeled distributions of spawning habitat and larval dispersal, and synthesized spatially indexed data from multiple independent sources from 1996 to 2016. Potential capelin spawning areas were broadly distributed across the GOA. Models of larval drift show the GOA’s advective circulation patterns disperse capelin larvae over the continental shelf and upper slope, indicating potential connections between spawning areas and observed offshore distributions that are influenced by the location and timing of spawning. Spatial overlap in composite distributions of larval and age-1+ fish was used to identify core areas where capelin consistently occur and concentrate. Capelin primarily occupy shelf waters near the Kodiak Archipelago, and are patchily distributed across the GOA shelf and inshore waters. Interannual variations in abundance along with spatio-temporal differences in density indicate that the availability of capelin to predators and monitoring surveys is highly variable in the GOA. We demonstrate that the limitations of individual data series can be compensated for by integrating multiple data sources to monitor fluctuations in distributions and abundance trends of an ecologically important species across a large marine ecosystem.


2005 ◽  
Vol 33 (1) ◽  
pp. 185-188 ◽  
Author(s):  
Csilla Farkas ◽  
Roger Randriamampianina ◽  
Juraj Majerčak

Sign in / Sign up

Export Citation Format

Share Document