Gone with the flow: Whitefish egg drift in relation to substrate coarseness under a range of flow velocities.

Most major rivers in Europe have been dammed for hydropower or other purposes. Such river alterations have decimated natural reproduction of many migratory fish species, including that of the anadromous European whitefish, Coregonus lavaretus, which is now maintained by extensive stocking programmes. In addition to stocking, limited natural reproduction may occur downstream of dams, where peak flow bouts from the dams threaten to flush the eggs into unsuitable habitats. Here, we assessed the effects of water flow velocity and substrate coarseness on downstream drift of whitefish eggs under laboratory conditions. The experiment's two different gravel substrates retained eggs better than cobble or sand substrates; the water velocity needed for notable egg drift was higher for the gravel substrates. The results indicate that egg drift is one of the factors that should be considered when evaluating the effects of hydropower plant operations. Moreover, measures mitigating the effects of the artificial flow regimes should incorporate the type and coarseness of the riverbed's substrate.

Cumulative Effects of Watershed Disturbances and Run-of-river Dams on Mercury Cycling: Case Study and Recommendations for Environmental Managers.

Run-of-river power plants (ROR) represent the majority of hydroelectric plants worldwide. Their environmental impacts are not well documented and are believed to be limited, particularly regarding the contamination of food webs by methylmercury (MeHg), a neurotoxin. RORs are typically installed in small rivers where combined effects of watershed disturbances with dam construction can complicate environmental management. We report a multi-year case study on the Saint-Maurice River (Canada) where an unpredicted temporary increase in MeHg accumulation in predator fish was observed after the construction of two ROR plants. The associated pondages acted as sedimentation basins for mercury (Hg) and organic matter from a watershed disturbed by a forest fire and by logging. This fresh organic carbon likely fueled microbial MeHg production. Hg methylation was more associated with environmental conditions than to the presence of Hg, and main methylating microbial groups were identified. A constructed wetland was a site of significant Hg methylation but was not the main source of the fish Hg increase. Organic carbon degradation was the main driver of MeHg accumulation at the base of the food chain whereas trophic levels explained the variations at the top of the food chain. Overall, carbon cycling was a key driver of Hg dynamics in this system, and ROR plants can cause temporary (ca. 12 years) Hg increase in food webs when developed in disturbed watersheds, although this increase is smaller than for large reservoirs. Recommendations for future ROR construction are to establish a good environmental monitoring plan with initial high temporal resolution and to consider recent and potential watershed disturbances in the plan.

The Unknown Abnormal Condition Monitoring Method for Pumped-Storage Hydroelectricity.

Pumped-storage hydroelectricity (PSH) is a facility that stores energy in the form of the gravitational potential energy of water by pumping water from a lower to a higher elevation reservoir in a hydroelectric power plant. The operation of PSH can be divided into two states: the turbine state, during which electric energy is generated, and the pump state, during which this generated electric energy is stored as potential energy. Additionally, the condition monitoring of PSH is generally challenging because the hydropower turbine, which is one of the primary components of PSH, is immersed in water and continuously rotates. This study presents a method that automatically detects new abnormal conditions in target structures without the intervention of experts. The proposed method automatically updates and optimizes existing abnormal condition classification models to accommodate new abnormal conditions. The performance of the proposed method was evaluated with sensor data obtained from on-site PSH. The test results show that the proposed method detects new abnormal PSH conditions with an 85.89% accuracy using fewer than three datapoints and classifies each condition with a 99.73% accuracy on average.

Role of hydroelectricity and natural gas consumption on environmental sustainability in the United States: Evidence from novel time-frequency approaches.

This study analyzes time- and frequency-varying impacts of hydroelectricity energy consumption, natural gas energy consumption, and economic growth on environmental sustainability proxied by carbon dioxide (CO2) emissions in the United States of America (the US) for the period 1965/Q1 to 2020/Q4. This study is the first of its kind to contribute to the current literature by analyzing dynamic relationships among these variables in the short-, medium-, and long-term at different time frequencies in the framework of a multivariate correlation, hence providing a more comprehensive picture about the impacts of these effective factors on CO2 emissions. To meet the objectives of the study, Wavelet local multiple local (WLMC), which is a recent novel methodology developed by Polanco-Martínez et al. (2020), is applied. Moreover, the Wavelet coherence (WTC) approach is used for robustness check. The outcomes provide fresh insights into the long-term dynamic correlations among hydroelectricity energy consumption, natural gas energy consumption, economic growth, and CO2 emissions. The study discovers a robust positive co-movement between natural gas energy consumption and CO2 emissions and a negative correlation between hydro energy consumption and CO2 emissions that is the most intense on the long-term frequencies. Furthermore, economic growth causes CO2 emissions, which is evidenced by a positive relationship between both factors at short- and long-term time-frequencies. Supported by the outcomes of the study, the authors urge to suggest crucial insights and policy points for the US policymakers to shift from fossil energy to renewable energy sources to meet Sustainable Development Goals (SDGs), especially SDG-7 and SDG-13, since they induce lower emissions.

How will hydro-energy generation of the Nepalese Himalaya vary in the future? A climate change perspective.

Despite being one of the proven clean-energy technologies, hydroelectricity is losing attention in global research. Hydroelectricity is extremely important for countries possessing the required water resources, already heavily reliant on it and those lacking the financial capacity to invest in other expensive energy technologies. This study assessed the possible impact of climate change (CC) on hydro-energy generation in the Nepalese Himalaya (possessing eight peaks out of 14 over 8000 m) with a tremendous hydropower potential (∼50,000 MW). A planned 1200 MW storage type Budhigandaki Hydroelectricity Project is taken as a case. We estimated the energy generation for the baseline as well as 10 CC scenarios considering RCPs 4.5 and 8.5 at monthly, seasonal, and annual temporal scales for the mid-century. Results show that energy generation is highly dependent on the reservoir operating rule. The average annual energy generation is expected to vary within -5 to +12% of the base case in the mid-century, with significant variations across the months. We also infer that designing hydro-projects based on ensembled climate values could lead to a "rosy" but less probable and risky picture of energy generation in the future. Therefore, assessment of a wide spectrum of plausible CC scenarios are recommended. Storage type projects with provision of flexible operating rules considering finer temporal resolution and allocation to competing users (in case of multipurpose projects) supported by appropriate policies are desirable for climate resiliency. Complementing the existing energy generation mix with other technologies in areas where hydroelectricity is expected to undergo adverse impacts of CC is warranted for attaining future energy security and environmental safeguarding. Possibility of additional energy due to CC is a strong motivation for this region to focus on hydroelectricity development in the future.

The self-reported behaviour of Iiyiyiu Aschii Cree and the worry about pollution from industrial and hydroelectric development in northern Quebec, Canada.

Worry is influenced by environmental pollution and affects individual health and well-being; however, little is known about this association in Indigenous communities. Using logistic regression models, we examined self-reported responses among Cree adults to the question "Are you worried about the pollution of the environment (land, water or air) in Iiyiyiu Aschii?" to assess if increased worry was associated with proximity to industrial and hydroelectric development, whether increased worry was associated with self-reported behavioural changes of water consumption type in the community or bush, and days spent on-the-land. Proximity to multiple industrial and hydroelectric development sites was associated with increased worry about pollution. Notably, the decreased consumption of tap water in the community was significantly associated with increased worry, but time-on-the land was not. Overall, our study provides new findings concerning development in a Cree territory in northern Quebec, Canada, and the worry about pollution's association with self-reported behavioural changes.

Limiting the high impacts of Amazon forest dieback with no-regrets science and policy action.

Large uncertainties still dominate the hypothesis of an abrupt large-scale shift of the Amazon forest caused by climate change [Amazonian forest dieback (AFD)] even though observational evidence shows the forest and regional climate changing. Here, we assess whether mitigation or adaptation action should be taken now, later, or not at all in light of such uncertainties. No action/later action would result in major social impacts that may influence migration to large Amazonian cities through a causal chain of climate change and forest degradation leading to lower river-water levels that affect transportation, food security, and health. Net-present value socioeconomic damage over a 30-year period after AFD is estimated between US dollar (USD) $957 billion (×109) and $3,589 billion (compared with Gross Brazilian Amazon Product of USD $150 billion per year), arising primarily from changes in the provision of ecosystem services. Costs of acting now would be one to two orders of magnitude lower than economic damages. However, while AFD mitigation alternatives-e.g., curbing deforestation-are attainable (USD $64 billion), their efficacy in achieving a forest resilience that prevents AFD is uncertain. Concurrently, a proposed set of 20 adaptation measures is also attainable (USD $122 billion) and could bring benefits even if AFD never occurs. An interdisciplinary research agenda to fill lingering knowledge gaps and constrain the risk of AFD should focus on developing sound experimental and modeling evidence regarding its likelihood, integrated with socioeconomic assessments to anticipate its impacts and evaluate the feasibility and efficacy of mitigation/adaptation options.

Using news coverage and community-based impact assessments to understand and track social effects using the perspectives of affected people and decisionmakers.

This paper applies an innovative approach to monitoring social effects occurring before and during construction of two hydroelectric dams in Canada. The two studied dams, Site C and Keeyask, are under construction in Canada and underwent community-based impact assessment (CBIA). News coverage and the CBIA documents were analyzed to understand and compare how those two groups perceive social effects induced by the two projects. CBIAs contain concerns expressed by affected people, whereas news coverage can include quotes from both affected people and decisionmakers involved in the assessment process. By contrasting these datasets, we found that the documents are complementary: while CBIAs are comprehensive in assessing community concerns, news outlets can reveal how those concerns evolved throughout different phases of the projects' implementation. This approach fills a gap in SIA around monitoring of key social effects around local conflicts and disputes, psychosocial effects, socioeconomic effects, and cumulative effects on a daily life. Furthermore, by contrasting the views identified within the impact assessments and the media, the study demonstrates how specific concerns diverged: affected people focus on local social effects while decisionmakers' interests lie in a broader political perspective grounded in local sacrifices 'for the good of the whole province'. Our analysis emphasizes the role of political power over decision making that can inhibit CBIA and social impact assessment practice from contributing to socially sustainable projects.

Dams have varying impacts on fish communities across latitudes: a quantitative synthesis.

Dams are recognised to impact aquatic biodiversity, but the effects and conclusions diverge across studies and locations. By using a meta-analytical approach, we quantified the effects of impoundment on fish communities distributed across three large biomes. The impacts of dams on richness and diversity differed across biomes, with significant declines in the tropics, lower amplitude but similar directional changes in temperate regions, and no changes in boreal regions. Our analyses showed that non-native species increased significantly in tropical and temperate regulated rivers, but not in boreal rivers. In contrast, temporal trajectories in fish assemblage metrics were common across regions, with all biomes showing an increase in mean trophic level position and in the proportion of generalist species after impoundment. Such changes in fish assemblages may affect food web stability and merit closer study. Across the literature examined, predominant mechanisms that render fish assemblages susceptible to impacts from dams were: (1) the transformation of the lotic environment into a lentic environment; (2) habitat fragmentation and (3) the introduction of non-native species. Collectively, our results highlight that an understanding of the regional context and a suite of community metrics are needed to make robust predictions about how fish will respond to river impoundments.

A new methodology for royalties distribution of the Itaipu hydroelectric plant: The hydrographic basin as the unit of analysis.

Over the past few years, many sectors such as energy generation, industry, domestic supply, and agriculture have encountered serious environmental problems due to the lack of rainfall. Thus, the purpose of this paper is to review the current methodology of royalties distribution from Itaipu hydroelectric plant. In the proposed approach, two criteria were considered to establish the division of Itaipu royalties: (1) the relative percentage of the water flow in the generation of electricity and, (2) the relative percentage of the drop in the height of water. 62 hydroelectric plants were evaluated in this study. In 52 plants the water flow was the factor that most contributed to the generation of electricity. In 2013, 346 municipalities benefited the Itaipu royalties. With the proposed methodology, 1,327 municipalities will receive the resource, what would increase the revenue of each of these municipalities by, on average, US$ 87,436.91 per year. The methodology presented herein proposes a reduction in the environmental disparity that now exists in Brazil, through improvement to Government instruments and environmental policies. The distribution of royalties throughout the watershed can provide additional resources to support payment programs for environmental services at the state and municipality levels.

The impact of electricity consumption on CO2 emission, carbon footprint, water footprint and ecological footprint: The role of hydropower in an emerging economy.

The primary objective of this paper is to investigate the isolated impacts of hydroelectricity consumption on the environment in Malaysia as an emerging economy. We use four different measures of environmental degradation including ecological footprint, carbon footprint, water footprint and CO2 emission as target variables, while controlling for GDP, GDP square and urbanization for the period 1971 to 2016. A recently introduced unit root test with breaks is utilized to examine the stationarity of the series and the bounds testing approach to cointegration is used to probe the long run relationships between the variables. VECM Granger causality technique is employed to examine the long-run causal dynamics between the variables. Sensitivity analysis is conducted by further including fossil fuels in the equations. The results show evidence of an inverted U-shaped relationship between environmental degradation and real GDP. Hydroelectricity is found to significantly reduce environmental degradation while urbanization is also not particularly harmful on the environment apart from its effect on air pollution. The VECM Granger causality results show evidence of unidirectional causality running from hydroelectricity and fossil fuels consumption to all measures of environmental degradation and real GDP per capita. There is evidence of feedback hypothesis between real GDP to all environmental degradation indices. The inclusion of fossil fuel did not change the behavior of hydroelectricity on the environment but fossil fuels significantly increase water footprint.

Land cover change explains the increasing discharge of the Paraná River.

Over the past 40 years, the discharge in South America's Paraná River basin has increased despite no evidence of significant rainfall increases in the basin. In this analysis, we show that the observed multi-decadal increase in discharge can be explained by concomitant changes in land cover that have occurred within the basin during this period. Our analysis also indicates that the peak discharge timing may have shifted concurrently from January/February in the 1970s to March in more recent decades. While land-use effect dominantly alters the long-term temporal dynamics of the river discharge over multi-decades, the change in the seasonality of the discharge can be attributable to the combined effect of the land-use and climate variability. This study suggests that the mean annual discharge is likely to change in the other South American River basins where land transformation is currently taking place, and the shift of the month of peak discharge needs to be taken into consideration to forecast the hydropower generation under changing climate and land conversion.

Itaipu royalties: The role of the hydroelectric sector in water resource management.

For countries dependent on hydroelectricity, water scarcity poses a real risk. Hydroelectric plants are among the most vulnerable enterprises to climate change. Investing in the conservation of the hydrographic basin is a solution found by the hydropower sector. Given the importance of the Itaipu plant to the energy matrix of Brazil and Paraguay, the aim of this study is to review the current distribution of royalties from Itaipu, using the hydrographic basin as a of criterion of analysis. Approximately 98.73% of the Itaipu basin is in Brazil. The flow contributes 99% of the total electricity generated there, while the drop height of the water contributes only 1%. Under the current policy, royalties are shared equally between Brazil and Paraguay. In the proposed approach, each country would receive a percentage for their participation in the drop height and water flow in the output of the turbines, which are intrinsic factors for electricity generation. Thus, Brazil would receive 98.35% of the royalties and Paraguay, 1.65%. The inclusion of the hydrographic basin as a criterion for the distribution of royalties will promote more efficient water resource management, since the payment will be distributed throughout the basin of the plant. The methodology can be applied to hydroelectric projects worldwide.

From Milk-Medicine To Public (Re)Education Programs: An Examination Of Anishinabek Mothers' Responses To Hydroelectric Flooding In The Treaty #3 District, 1900-1975.

This paper explores how Anishinabek women managed their households during the hydroelectric boom of the 1950s and provides new insight into flooding impact analyses. To date, historians have sought to understand how hydroelectric development compromised "subsistence" living. Research has addressed declining fish and game populations and the corresponding decline in male employment. But, what do these trends mean once the nets and traps have been emptied? By focusing on the family home, we discover that hydroelectric power generation on the Winnipeg River disrupted the environment's ability to provide resources necessary to maintain women's reproductive health (especially breast milk). Food shortages caused by hydroelectric development in the postwar era compromised Anishinabek women's ability to raise their children in accordance with cultural expectations. What emerges from this analysis is a new lens through which to theorize the voluntary enrolment of Anishinabek children in residential schools in northwestern Ontario.

Recent Advances in Fibrous Materials for Hydroelectricity Generation.

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable development. Hydroelectricity generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy crisis. Fibrous materials with unique flexibility, processability, multifunctionality, and practicability have been widely applied for fibrous materials-based hydroelectricity generation (FHG). In this review, the power generation mechanisms, design principles, and electricity enhancement factors of FHG are first introduced. Then, the fabrication strategies and characteristics of varied constructions including 1D fiber, 1D yarn, 2D fabric, 2D membrane, 3D fibrous framework, and 3D fibrous gel are demonstrated. Afterward, the advanced functions of FHG during water harvesting, proton dissociation, ion separation, and charge accumulation processes are analyzed in detail. Moreover, the potential applications including power supply, energy storage, electrical sensor, and information expression are also discussed. Finally, some existing challenges are considered and prospects for future development are sincerely proposed.

Does hydropower production influence agriculture industry growth to achieve sustainable development in the EU economies?

There are many advantages of the hydropower industry, as an environmentally friendly resource, and also some challenges that need to be overcome to fully exploit this sustainable and renewable natural resource. The primary objective of this study is to find out the impact of hydropower factors and economic growth on the agriculture industry output among the EU27 nations within the time factor 1990 to 2021. Adopting the autoregressive distributed lag (ARDL), the findings show a significant positive effect could occur in agriculture industry growth of the European Union (EU13)-emerging economies using hydropower factors than in EU14-emerged economies. On one hand, among additional factors, economic growth and institutional quality contribute more positively to agriculture growth in EU13 economies than in EU14 economies. On the other hand, population density contributes more negatively to agriculture growth in EU13 economies than in EU14 economies. The findings show there can be a positive significant growth increase in the EU13 agriculture industry using fossil fuel output than in EU14 economies. The results show that growth could be sustained in the agricultural industry of the European nations by increasing the level of hydropower production as this will help in attaining sustainable development by the year 2030. This will therefore help in mitigating the effect of climatic changes due to environmental pollution. The projected calculations were seen to be reliable and valid and this was attested to by the three estimators used in the study (pooled mean group, mean group, and dynamic fixed effect). This study recommended that European nations could leverage hydroelectricity to achieve sustainable growth and development. The legislative arms of the government of these European nations should as well show more interest in green energy to achieve security and sustainable development in hydroelectricity production. Decision-makers in the EU nations should buttress more emphasis on sustainable means through which hydropower could be used to attain sustainable irrigation systems for the agriculture industry and thus minimize the demand for fossil fuels and reduce CO2-related emissions in the future tine ahead.

Freshwater species diversity loss embodied in interprovincial hydroelectricity transmission with ecological network analysis.

A major strategy for addressing the imbalance in source-network-load distribution is interprovincial electricity transmission; however, this process also causes various environmental effects. Previous studies have mainly examined thermal power transmission, and few insights have been gained into the challenges hydroelectricity transmission poses for biodiversity conservation. Here, we innovatively incorporated the freshwater species diversity footprint into a hydropower environmental impact assessment, calculating the interprovincial transfer of freshwater species diversity embodied in hydroelectricity transmission. We proposed an evaluation model of an interprovincial hydroelectricity transmission network using freshwater species diversity as the ecological element and creatively identified significant nodes and paths of the network. Up to 28% of the transfer of freshwater species diversity was related to the demand for hydroelectricity consumption in Shanghai. 64% of the relationships in the hydroelectricity transmission network were implemented at the expense of ecological losses on one side. Shanghai and Sichuan provinces and some transmission lines related to them were significant nodes and paths for improving the overall status of the network. This research can help policymakers comprehend the challenges to freshwater species presented by interprovincial hydroelectricity transmission and serve as a reference for ecological compensation for hydropower development.

Contribution of the mix renewable energy potentials in delivering parts of the electric energy needs in the west region of Cameroon.

The constant supply of energy remains a great challenge in many developing countries and Cameroon is no exception. It is necessary to explore other renewable energy sources that have environmental and energy potential. However, there is limited and sparse literature on the potential of renewable energy sources in Cameroon and its western part in particular. This limits investment and policy design that can lead to the exploitation of renewable energy sources. There is thus a need for more research on renewable energy development to better inform energy policies. This paper investigates the potential and extent to which available renewable energy sources can contribute to the electric power sector in the western part of Cameroon is on estimating the potential of hydroelectric, solar and biomass energy resources. A cross-sectional method, observations and literature review were used to determine the water flow and electrical energy potential of different biomass. The results show that the electrical potential of hydroelectricity is 11.68 GWh/year, for solar represents 44.12 GWh/year, and the energy of biomass 8586.42 GWh/year, 135.53 GWh/year and 13.05 GWh/year for agricultural, animal and forestry residues; they have a rate of access to electricity of 6.64%, 25.08%, 4881.46%, 77.05%, and 7.42% respectively. This potential can satisfy needs of 18 526 464 households. According to results obtained and in order to provide a sustainable solution by improving access to electricity, living standards and socio-economic conditions of populations; two hybrid cogeneration thermal-solar power plants can be installed at the limits of the decentralized areas of Bamboutos-Mifi-Menoua and Noun-Koung Khi, which are nearby areas with high population density. Hydroelectric plants can be installed to electrify villages that are far from the national network.

Life cycle assessment and optimization scenario of solid wood composite doors: A case study in the east of China.

The large scale of the Chinese wooden door market has resulted in a slew of environmental issues that must be addressed. This paper evaluated a solid wood composite door using life cycle assessment (LCA). Field research was used to obtain production data for the wooden door. The production stages were divided into the raw material stage, the transportation stage, the woodworking workshop stage, and the painting workshop stage in order to identify potential environmental improvements and analyze the underlying causes to offer some suggestions for improvement. Four service lives were considered in the use stage, and three disposal methods were considered in the disposal stage to explore their environmental impacts. The functional unit was defined as a solid wood composite door using the "cradle-to-grave" system boundary. Using a 20-year service life as an example, the results revealed that the production stage was the most crucial stage, with a contribution ratio of 49% to 72% to all impact categories, regardless of waste disposal method. The main reasons for this were the production of density boards and the consumption of electricity. By replacing straw-density boards and hydropower, the global warming potential (GWP) was reduced by 46% and 67%, respectively. If a wooden door can be used for 20 years, the use stage will account for 26% to 51% of the environmental impact contribution, owing primarily to wood wax oil. Recycling was recognized as the most environmentally friendly method of waste disposal. This research can be used as a reference for evaluating solid wood composite doors in China as well as providing optimization recommendations for production improvement.

Straw density board vs. conventional density board: Is straw density board more sustainable?

The widespread use of density boards in various industries has caused a series of environmental issues. The results of this study can inform policy-making and facilitate the sustainable development of density boards. The research focuses on the comparison between 1m3 conventional density board and 1m3 straw density board, with the system boundary defined as "from cradle to grave." Their life cycles are evaluated across three stages: manufacturing, utilization, and disposal. To facilitate environmental impact comparisons, the production stage was divided into four scenarios based on different power supply techniques. To identify the environmental break-even point (e-BEP), variable parameters for transport distance and service life were incorporated into the usage phase. The disposal stage evaluated the most prevalent disposal method (100 % incineration). Regardless of the power supply method, the total environmental impact of conventional density board throughout its life cycle is always higher than that of straw density board, owing to the large amount of electricity consumption and the utilization of urea-formaldehyde (UF) resin adhesives in the raw material stage of conventional density boards. During the production stage, while the conventional manufacture of density boards results in environmental impacts ranging from 57 % to 95 %, which surpasses those of straw-based alternatives at 44 % to 75 %, modifying the power supply technique can alleviate such impacts by 1 % to 54 % and 0 % to 7 %, respectively. Thus, altering the power supply technique can effectively mitigate the ecological footprint of conventional density boards. Moreover, when assuming a service life, the remaining eight environmental impact categories exhibit an e-BEP at or prior to 50 years, with the exception of the primary energy demand (PED) values. Based on the environmental impact results, relocating the plant to a more judicious geographical location would indirectly increase the break-even transport distance and consequently mitigate the environmental impact.