Climate Change and Impacts on Freshwater Ecosystems

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Impact of climate change on freshwater ecosystems: a global scale analysis of ecologically relevant river flow alterations

Impact of climate change on freshwater ecosystems: a global scale analysis of ecologically relevant river flow alterations

Most analyses of climate change impacts on freshwater ecosystems focused on the impact of temperature changes (Millenium Ecosystem Assessment, 2005; Fischlin et al., 2007). Some considered changes in mean precipitation, as a surrogate variable for river flows (Buisson et al., 2008; Lasalle and Rochard, 2009). Few analyses considered the effects of changing water flows. Kundczewicz et al. (2007) reviewed some publications that deal with the impacts of climate change induced river flow alterations on freshwater ecosystems, discussing decreased habitat availability due to decreased ice-jam flooding, impacts of lower water column depth on spawning of salmon, and impacts of reduced runoff on breeding grounds for water birds. In a review on the im- pact of climate and land use change on Alpine brown trout, Scheurer et al. (2009) concluded that climate change in- duced increases of river discharge and sediment loads in win- ter and early spring could be especially harmful for brown trout reproduction and development of young life stages. Er- win (2009) reflected on the challenges to wetland conserva- tion and restoration under climate change, pointing out the need to reduce non-climate stressors, including monitoring, in particular of invasive species that are favored by climate change. He warned that a number of wetlands will disappear due to climate change, especially the drier-end wetlands. As- sessing the impacts of climate change on waterbirds that de- pend on inland freshwater systems, Finlayson et al. (2006) also indicated semi-arid and arid regions as major vulnerable regions.
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Global climate change and aquatic ecosystem: potential impacts and challenges

Global climate change and aquatic ecosystem: potential impacts and challenges

Freshwater ecosystems cover 0.78% of the Earth's surface and generate nearly 3% of its net primary production. Freshwater ecosystems contain 41% of the world's known fish species. Fresh waters are particularly vulnerable to climate change because they are relatively isolated and physically fragmented and they are heavily exploited by humans. Above about a 4 °C increase in global mean temperature by 2100 (relative to 1990- 2000), Schneider et al. (2007:789) concluded, that many freshwater species would become extinct. Several other drastic effects of climate change on fresh water ecosystem include earlier breeding in amphibians (Beebee 1995), earlier emergence of dragonflies (Odonata) (Hassall et al. 2007), and compositional shifts of entire insect communities (Burgmer et al. 2007). The extreme events (floods and droughts), modify water quality through direct impacts of dilution or concentration of dissolved substances. More intense rainfall and flooding could result in increased loads of suspended solids (Lane et al. 2007) and contaminant fluxes (Longfield and Macklin 1999) associated with soil erosion and fine sediment transport from the land (Leemans and Kleidon 2002). Reduced dilution will increase organic pollutant
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Impacts of Climate Change on the European Marine and Coastal Environment - Ecosystems Approach

Impacts of Climate Change on the European Marine and Coastal Environment - Ecosystems Approach

Recent projections of future climate scenarios indicate continued warming with temperature increases in the order of 2-10°C over this century (ACIA 2005). Increased precipitation will result in higher river runoff adding to the freshwater additions through ice melt. In the absence of ice, surface waters will be exposed to wind-driven circulation (ACIA 2005). The Transpolar Drift would shift eastwards to favour flow directly toward the Fram Strait. The Beaufort Gyre may weaken and retreat into the Canada Basin with the position of Atlantic/ Pacific Front tending to align permanently with the Mendeleyev-Alpha Ridge. Also, when summer ice retreats seaward of the continental slope, enhanced deep basin–shelf exchange of seawater will occur through increased wind-induced upwelling and downwelling (Carmack and Chapman 2003). The retraction of the sea-ice and the enhanced exchange of deep-basin seawater will result in higher light levels and nutrient concentrations on the shelves, leading to increased primary production. Wind-driven vertical mixing is likely to increase the depth of the surface mixed layer. If the Arctic becomes ice-free in winter, the Nansen Basin may become a region of strong convection (sinking of cold dense water) and water mass formation. Predicted strengthening of the westerly winds in the Nordic Seas is expected to increase the transport of Atlantic water entering the Arctic via the Fram Strait and the Barents Sea (ACIA 2005).
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A transdisciplinary approach to the economic analysis of the European Water Framework Directive

A transdisciplinary approach to the economic analysis of the European Water Framework Directive

4 Acknowledgements 5 6 7 8 9 10 11 12 13 This work has been co-funded by the REFRESH Project: Adaptive Strategies to Mitigate the Impacts of Climate Change on European Freshwater Ecosyst[r]

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Perception of Climate Change and Livelihood of a Farming Community of Maruf Kebele, Central Oromia, Ethiopia

Perception of Climate Change and Livelihood of a Farming Community of Maruf Kebele, Central Oromia, Ethiopia

ty [1], but rapid population growth and environmental degradation acted to diminish the outcome of this success in many countries like Ethiopia [2]. With continued increase in population pressure and land holdings conti- nuously shrinking, many poor smallholders have resorted to more frequent cropping, curtailing traditional long fallows and increased use of inorganic fertilizers [3]-[6]. Ethiopia is one leading Sub-Saharan country to liberal- ize its economy and develop poverty reduction strategies through market-led, broad based agricultural develop- ment during early 2000s, so in the 2012/13 fiscal year Ethiopia’s economy grew by 9.7%, the tenth year in a row of robust growth. Agriculture, which accounted for 42.7% of GDP, grew by 7.1%, while industry, accounting for 12.3% of GDP, rose by 18.5% and services, with 45% of GDP, increased by 9.9% in 2012/2013. Although Africa’s average growth declined from 5% in 2010 to 3.4% in 2011, the Ethiopian economy continued on the high-growth trajectory, and this momentum was expected to continue in 2012 and 2013 [7]. However, the growth in economy has been unevenly distributed, in most rural areas lasting effects of poverty, hunger, malnu- trition still weigh heavily on the Ethiopian economy [8]. As 93% of Ethiopians are currently engaged in small scale agriculture and other manual intensive activities, economic loss due to malnutrition estimated to cause re- duced productive capacity at ETB 12.8 billion in 2009 (1 ETB = 0.5 US$) which is equivalent to 3.8% of GDP [9]. Ethiopia being the second most populous country in Africa (more than 82.9 million people), the rural popu- lation accounting for 82.4% [11], majority depending on traditional rainfed agriculture in the small farm domi- nated agriculture sector, the stability and sustainability of development have been heavily dependent on climate. Traditional agriculture, dominated by non-mechanized farming in highly uneven landscape, small-scale farmers
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The Climate Change Dynamics and its Impact on the Wheat Productivity in Pakistan: A VAR Approach

The Climate Change Dynamics and its Impact on the Wheat Productivity in Pakistan: A VAR Approach

As the farmers across the country are mostly illiterate, they need to know that changes in climate will lead to reduction in the output so need to have in time knowledge as in the long run these changes will affect the farmers throughout the country. The temperature may shorten the growth periods; hence the cultivation should be adjusted accordingly. The government has to take initiative to introduce the high temperature resistant seeds as the increase in temperature in future will affect the productivity. Climate change also alters the rain fall pattern across the country; therefore it is necessary for researchers to introduce the drought resistant seeds. The recent floods in the country have destroyed almost all major crops, the government need to store the excess water by constructing more dams as the floods leave the soil more fertile after it ruin all the land once.
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Climate change and livestock farming in Cameroon: impacts and implications for poverty reduction

Climate change and livestock farming in Cameroon: impacts and implications for poverty reduction

The paper examines the distributional implications of income derived from livestock farming on poverty, and assesses the impact of climate change on livestock income in Cameroon. The analyses are based on primary data collected from a sample of 801 households in 2004. The primary data were enriched with secondary climate data, which reflect long term climate change in Cameroon. The impact of climate change on livestock income is analyzed using the Ricardian approach. It comes out of the analyses that households whose incomes are below the poverty line have a significant positive relation with livestock income. This implies that for such households, livestock farming activity is considered an important safety net required for overcoming poverty. This finding highlights the importance of income from livestock farming for the alleviation of poverty in the country. Livestock farming is an important source of income for many Cameroonian households. Without it, many households’ ability to satisfy their basic needs would be jeopardized. The simulation results reveal that ignoring this income source when estimating poverty measures in Cameroon would substantially overestimate the impacts on household poverty, which is all the more pronounced at the regional levels, especially at the northern parts of the country where most households depend on livestock activities for their livelihood. The policy implication here is that policy makers (especially the Ministry of Livestock, Fisheries and Animal
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The Future of European Electricity: Choices before 2020. CEPS Policy Brief No. 164, 8 July 2008

The Future of European Electricity: Choices before 2020. CEPS Policy Brief No. 164, 8 July 2008

The electricity sector plays a central role in the European Union’s efforts to achieve greenhouse gas (GHG) reductions of at least 20% by 2020 compared to 1990 levels. While the electricity sector is currently responsible for about one-third of Europe’s total energy-related GHG emissions, there are large potentials for reducing emissions. Mitigation strategies will need to focus on more efficient electricity use, but also on improved conversion rates and new technologies such as renewables and carbon capture and storage (CCS). Apart from mitigation of climate change, the sector will also have to adapt to climate change. Global warming will have a significant impact on the ability to generate electricity and to deliver it without interruption. This ADAM-CEPS Policy Brief focuses on four issues relevant to the nexus between climate change and the electricity sector. The paper first elaborates on the impacts of climate change on the European electricity sector and on related adaptation needs. Southern countries will most likely be faced with less demand for heating but substantially increased demand for air conditioning. They may also experience losses in hydropower and problems with cooling of thermal power plants. Northern countries will equally experience less demand for heating and may gain potential for electricity production from hydropower. At the same time, they may have to adapt to more storms and heavy precipitation. In both regions, electricity supply disruptions due to storms, floods and heat waves may increase the need for more decentralised electricity generation in order to avoid negative impacts on electricity users. The next section focuses on policy options to facilitate the transition of the electricity sector towards a well-adapted, carbon-lean electricity system. A stable and predictable policy framework is a necessary precondition for investment decisions by the private sector. However, policy instruments need to be assessed according to their effects on wealth distribution, choice of technology and time horizon. Similarly, affected groups (e.g. producers, investors, industries, households) need to be taken into account to enhance the political feasibility of policy interventions. Many EU member states are likely to opt for combinations of policy instruments in order to overcome various sectoral or technology- specific barriers and to promote non-fossil options with substantial innovative and cost-reduction potentials.
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Numerical modelling of climate change impacts on freshwater lenses on the North Sea Island of Borkum using hydrological and geophysical methods

Numerical modelling of climate change impacts on freshwater lenses on the North Sea Island of Borkum using hydrological and geophysical methods

The altitude of the groundwater table was mapped and vi- sualised. Due to the enhanced annual precipitation scenarios we used an enhanced, linearly increasing annual groundwater recharge of +10 % for 2100 (average scenario) and an an- nual recharge of +5 % for 2100 (conservative scenario). For the delivery rates of WW I and WW II a constant value of 380 000 m 3 a −1 (average delivery 1934–2010) and 480 000 m 3 a −1 (average delivery 1971–2010) was used, re- spectively. Model computations reveal that due to the inertia of the freshwater lens model seasonal variations of the de- livery rates are negligible. To achieve correct prognosis re- sults, the level of constant head boundary conditions repre- senting the surface of the sea water was shifted for each time step during simulation by means of a linear function, begin- ning with 0 m in the year 2010 and ending with 0.96 in the year 2100. Moreover, the area covered by boundary condi- tions of this type had to be extended more towards the shore according to the risen mean sea level (Fig. 17, right panel). Additionally, the mass transport boundary conditions were adapted to the full sea water concentration in areas consis- tent with the progressed mean high tide for 2100 (blue area in Fig. 17, right panel).
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Climate forcing and sudden change in marine ecosystems

Climate forcing and sudden change in marine ecosystems

Fishing effects in marine ecosystems may act synergistically with other forcing mechanisms, notably climate change, coastal eutrophication and habitat loss (Harley et al. 2006, Crowder et al. 2008), in a way that makes regime shifts and "ecological surprises" likely (deYoung et al. 2008). Given the poor global record of achieving fisheries sustainability (Worm et al. 2009), a tool that would provide early warning of impending non-linear behavior in exploited stocks and communities would be an important addition to fisheries management. Our results support the use of one proposed generic regime shift indicator – increased spatial variability – to predict fisheries collapse. While the considerable noise inherent in many marine populations creates a challenge for detecting statistically significant trends (Nicholson and Jennings 2004), and the time series in our study were quite short (mean = 17 years prior to collapse), we found evidence for increasing variability prior to collapse when an overall trend in variability was estimated across all collapsing fisheries (P = 0.0002). However, although sample size for most fisheries (Fig. 4.2B) achieved the sampling intensity (n = 28 – 50) found necessary to detect spatial indicators of regime shifts in experimental manipulations (Carpenter et al. 2011, Seekell et al. 2012), we only detected statistically significant increases in spatial variability prior to collapse in four of 12 collapsing fisheries (Fig. 4.3). The considerable difference among populations in variability trends that we observed suggests that efforts to use this indicator for single populations may require levels of statistical power that are rarely available in management situations (Perretti and Munch 2012). Tests for change in variability across multiple populations, as we have presented here, may be a more realistic approach.
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Predicting recovery of acidified freshwaters in Europe and Canada: an introduction

Predicting recovery of acidified freshwaters in Europe and Canada: an introduction

The RECOVER:2010 project was designed to assess the current and future anthropogenic pressures on sensitive European freshwater ecosystems. This pan–European assessment utilised a standardised predictive modelling approach to evaluate the degree of compliance with respect to the restoration of acidified waters by 2016, as specified under the EU Water Framework Directive (WFD), and evaluated the environmental benefits of proposed UN-ECE protocols on emissions control. Between 1970 and 2000, observations and model simulations show a significant decline in acidic surface water in all regions of Europe. This demonstrated the success of policies aimed at reducing emission of acidifying compounds. The nature and extent of future regional recovery from acidification is, however, dependent upon the historical pattern of deposition, regional ecosystem characteristics and the role of confounding factors, which may delay the onset of recovery or the magnitude of response. Model predictions to 2010 and beyond emphasise the continued benefit of currently proposed reductions, as reflected by the degree of recovery of freshwater ecosystems. A key component was to link such hydrochemical recovery with ecological response, and the project aimed to evaluate this against current WFD criteria of “good status” and “reference conditions”. The RECOVER:2010 project research has also played a major role in defining the dynamic modelling outputs which will be required to support the review of the Gothenburg Protocol within the work of the UN-ECE CLRTAP Working Group on Effects (WGE), and model outputs have been made available to a range of national agencies throughout Europe.
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Simulation of CO2 enrichment and climate change impacts on soybean production

Simulation of CO2 enrichment and climate change impacts on soybean production

flexibly employed for reproducing production responses at a broader geographical scale and for a wider range of conditions. In addition, crop growth models are capable of reproducing physiological responses. Crop growth simula- tion models have been widely used by many scientists to study crops grown in various environmental conditions. Well-calibrated and highly tested agricultural system mod- els are essential tools for integrating various chemical, physical, and biological processes and their interactions in agronomic systems (Ma et al., 2008). Such models can pro- vide daily or seasonal overall simulations of biomass, leaf, root, and other organ development in addition to yield and other related parameters. The CROPGRO modules in deci- sion support system for agro-technology transfer (DSSAT) software (Jones et al., 2003) are valuable tools for scien- tific research, field management, and policy-making (Boote et al., 1996). Sau et al. (1999) used CROPGRO to simu- late soybean growth in several non-stressed conditions. Ruı́z-Nogueira et al. (2001) also applied the model for simulations of soybeans grown under water-limited condi- tions. Irmak et al. (2005) used the model to predict yields under various combinations of precipitation, temperature, and solar radiation conditions at an aggregate scale in high- latitude regions, and they summarized and discussed the methods for estimating soybean yield by using grid cells. Roberto et al. (2006) investigated the responses of soybean and maize crops to individual and simultaneous climate change variables of precipitation, solar radiation, and tem- perature. Most studies focus on the response of soybean yield to individual environmental factors; few have evalua- ted model performance for simulations of soybean grown in elevated CO 2 conditions.
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Climate Change and Its Impact on Sustainable Development in Bangladesh

Climate Change and Its Impact on Sustainable Development in Bangladesh

Abstract: There has been a large scientific evidences on climate change and its direct as well as indirect influences. Every year around 2.5 million people die from non-infectious diseases, which are directly attributable to environmental factors and these are related to climate changes. So Climate change is one of the most important issues in present senario. Changes in conditions and climate variability affect temperature, sea level rise, poverty, rising salinity, greenhouse effect and it can also affect human health both directly and indirectly. Though Bangladesh is a very low energy consuming country, Bangladesh is one of the top 10 nations that are mostly vulnerable to climate changes. This study was carried out by employing a general review of literature on climate change, focusing on its effects in Bangladesh and sustainable development. The effects would be as Crop production will decrease, floods are contaminating water that Increasing water borne diseases such as cholera, diarrhea etc. If the global temperature rises by 2°C, 30% of all land species will be threatened by an increased risk of extinction. About 75% area of mangrove forest Sundarban will submerse if the sea level will increases 45 cm. The southwestern coastal districts of Bangladesh will increase 16% in 2050 and 18% in 2100, which will make people homeless and bring social instability.
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Ensembles and uncertainty in climate change impacts

Ensembles and uncertainty in climate change impacts

Several approaches may be taken to assessing the appropri- ate level of model integration and complexity for a particular purpose. Testing for relationships between observed impact (e.g., crop yield) and weather would provide a top-level justification for combining models of impact and climate (e.g., Challinor et al., 2003), as would the existence of significant feedbacks between impact and climate (e.g., river flow impact on ocean circulation; carbon cycle; or albedo). Several authors have selectively removed model components or fixed parameters, and then retested model performance (e.g., Crout et al., 2009; Tarsitano et al., 2011). This may be challenging with large, complex models. The appropriate level of model integration will also depend on the time and space scale in question, the location, climate and needs of stakeholders (Challinor et al., 2009a).
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Impact of climate change on arid lands agriculture

Impact of climate change on arid lands agriculture

It is anticipated that the impact of climate change will cut across all boundaries. Crops, cropping systems, rotations and biota will undergo transformation. To maintain the balance in the system, there is a need for new knowledge, alternative policies and institutional changes. The marginalized people in dry areas are likely to be most seriously hit by the shifts in moisture and temperature regimes as a result of the global climate change. To help them cope with the challenges, there is a need for a new paradigm in agricultural research and technology transfer that makes full use of modern science and technology in conjunction with traditional knowledge. This necessitates more investment by international agencies and national governments for supporting the relevant integrated research and sustainable development efforts, with full participation of the target communities. Only such an approach can enable the vulnerable communities of the dryland areas to use the natural resources in a sustainable manner and thus help protect the environment for future generations.
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Effects of Climate Change on Grassland Biodiversity and Productivity: The Need for a Diversity of Models

Effects of Climate Change on Grassland Biodiversity and Productivity: The Need for a Diversity of Models

the impacts of climate change on biodiversity and productivity of grasslands.. We first discuss the.[r]

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CLIMATE CHANGE AND ITS IMPACTS ON AGRICULTURE

CLIMATE CHANGE AND ITS IMPACTS ON AGRICULTURE

Agriculture provides employment for 2.6 billion people worldwide and accounts for 20 to 60 percent of the gross domestic product of many developing countries, forming the backbone of rural economies, contributing to local employment, and ensuring food security for poorer populations. The agricultural sector is also a major contributor to GHG (Greenhouse Gas) emissions. Most studies attribute about twenty to twenty-five percent of all global GHG emissions to the production of food, feed, and biofuels, including emissions from agriculture- driven land use change. Though these numbers are substantial and comparable in aggregate to the transportation sector, agriculture’s potential contributions to GHG mitigation have received little attention the international dialogs on climate change mitigation. If agricultural systems are to meet the future needs of an expanding global population, significant progress will need to be made in helping the agricultural sector as a whole— and farmers in particular—increase the resilience of farming systems to climate change, better preserve soil fertility and freshwater flows, and reduce impacts on deforestation, biological diversity, and GHG emissions.
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Impacts of Climate Change on India: An Analysis

Impacts of Climate Change on India: An Analysis

great role in the health of flora and fauna of any region. Any change in the climate can cause enormous loss of biodiversity affecting both individual species and their ecosystems in turn affecting our economic growth and well being. It is very difficult to estimate the overall result of Climate Change on animal and plant Kingdom. If the present scenario continues to exist, it can cause devastating effects on the native habitats of many plants and animals; and may lead to their extinction. Mass extinctions of the earth's flora and fauna have occurred before also, but it happened through natural process. However, if there will be extinctions of flora and fauna it will be only due to adverse impact of human activities. The exponential growth of human population around the world along with the increasing pollution and loss of habitat is setting the conditions for mass extinctions large
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Challenges of mainstreaming climate change adaptation in Bangladesh

Challenges of mainstreaming climate change adaptation in Bangladesh

Information-based instruments for adaptation Reliable information on different aspects of climate change such as probable timing, extent and impacts of climate change, knowledge of droug[r]

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An ecohydrological sketch of climate change impacts on water and natural ecosystems for the Netherlands: bridging the gap between science and society

An ecohydrological sketch of climate change impacts on water and natural ecosystems for the Netherlands: bridging the gap between science and society

Given the uncertainties of the future climate and the response of ecosystems, no conclusions can be drawn that may have far-reaching consequences, such as giving up certain nature targets because they would no longer be feasible in the fu- ture climate. However, one could at least anticipate possi- ble negative effects of climate change by taking a number of adaptation measures that enhance the robustness of na- ture reserves. Desiccation of wet heaths and rain-fed moor- land pools can be combated by converting highly evaporating dark coniferous woods into less water consuming deciduous forests, grasslands or heathlands. Also damming of gullies, insofar as they are still present from e.g. the former buck- wheat fire cultivation, is a way to prevent water loss and stimulate groundwater recharge. External measures are the creation of hydrological buffer zones, increasing surface wa- ter levels in agricultural areas, a ban on sprinkling during prolonged drought periods and re-allocation or closing of groundwater abstraction wells. Linking nature areas and en- larging their size makes it easier to maintain high ground- water and surface water levels in relation to the surround- ings and increases the supply of upwelling alkaline ground- water into the root zone of plants. In addition, this measure helps species to disperse to locations that offer favourable habitats in the future of ecological networks. The European Natura 2000 network and climate adaptation zones for wet- land ecosystems are examples of an adapted spatial planning aimed at linking and enlarging nature areas (Vos et al., 2010). In nature areas with a controlled water level, such as fens, a more flexible water regime can help to significantly reduce the inlet of surface water of poor quality. The need for inlet- water for fens may also be reduced by minimizing down- ward seepage through a number of external measures: sub-
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