Wang, P., J.P. Lassoie, S. Dong, and S.J. Morreale, 2013: “A framework for social impact analysis of large dams: A case study of cascading dams on the Upper-Mekong River, China.” Journal of Environmental Management, v. 117, pp. 131-140, doi: 10.1016/j.jenvman.2012.12.045.
Construction of large dams on the Upper-Mekong River, China, has significant social impacts on local communities. To analyze the social impacts, we identified three classes of wealth for the affected people, material, embodied, and relational, and comprehensively compared the loss and compensation in each type of wealth. Then we examined the effects on gap of wealth at household and community levels. Lastly, an insider–outsider analysis was conducted to understand the differences in the perceptions of wealth loss between local villagers and policy makers, and recommendations for more reasonable compensation policies were provided.
Pal, I., U. Lall, A.W. Robertson, M.A. Cane, and R. Bansal, 2013: “Diagnostics of Western Himalayan Satluj River flow: Warm season (MAM/JJAS) inflow into Bhakra dam in India.” Journal of Hydrology, v. 478, pp. 132-147, 10.1016/j.jhydrol.2012.11.053.
Here we analyze the variability of MAM (March–April–May) and JJAS (June–July–August–September) seasonal Satluj River flow into the Bhakra dam in India through Pearson anomaly correlation and composite analyses with antecedent and concurrent seasonal climatic and atmospheric circulation patterns. The MAM seasonal inflow of Bhakra dam is significantly correlated with winter (DJF/FM) precipitation and temperature of the Satluj basin while the correlation with FM was more prominent for precipitation (snow = +0.72, rainfall = +0.60), and temperature (diurnal temperature range (DTR) = −0.76 and maximum temperature (Tmax) = −0.57). The JJAS inflow was also positively correlated with DJF/FM as well as JJAS precipitation of the Satluj basin while the correlation with basin average FM was the largest (+0.54). These suggested that both MAM and JJAS inflow anomalies are linked with DJF/FM climate over the Western Himalayas and adjoining north and central Indian plains, which were also found to be linked with the fluctuation of equatorial concurrent Sea Surface Temperature anomalies over the western Indian Ocean (max anomaly correlation was > +0.70) and mean sea level pressure over western pole of the Southern Oscillation sea-saw region (max Pearson anomaly correlation was ∼ +0.60). Low (high) MAM inflow was found to be associated with negative (positive) precipitation anomalies over the basin and north India in DJF and FM while FM precipitation anomaly is more concentrated over the Western Himalayas. In addition, low (high) JJAS inflow is also associated with negative (positive) precipitation anomalies over the basin and north India in DJF and over the Western Himalaya in FM and JJAS. Negative geopotential height anomaly at 500 hPa (Z500) over Siberia and northwestern pacific in DJF, and positive Z500 anomaly over the northwest India in FM were noticed in low MAM inflow years. Whereas high inflow in MAM was linked with a negative Z500 anomaly between two positive Z500 anomaly regions – one over eastern Siberia stretched up to northern Pacific and second over the Eastern Europe in DJF, which gets stronger in FM. We also found southwesterly (northeasterly) wind vectors at 850 hPa pressure level (uv850) bringing more (less) moisture to the Western Himalayas in DJF and FM in high (low) MAM/JJAS flow years.
Brown, J., K.E. Limburg, J.R. Waldman, K. Stephenson, E.P. Glenn, F. Juanes, and A. Jordaan, 2013: “Fish and hydropower on the U.S. Atlantic coast: Failed fisheries policies from half-way technologies.” Conservation Letters, doi: 10.1111/conl.12000.
Globally, diadromous species are at risk from fragmentation by damming of rivers, and a host of other anthropogenic factors. On the United States Atlantic Coast, where diadromous fish populations have undergone dramatic declines, restoration programs based on fishway construction and hatcheries have sustained remnant populations, but large-scale restoration has not been achieved. We examine anadromous fish restoration programs on three large Atlantic Coast rivers, the Susquehanna, Connecticut, and Merrimack with multiple mainstem hydropower dams, most with relatively low generating capacity. Mean passage efficiencies through fishways on these rivers from the first dam to the spawning grounds for American shad are less than 3%. The result is that only small fractions of targeted fish species are able to complete migrations. It may be time to admit failure of fish passage and hatchery-based restoration programs and acknowledge that significant diadromous species restoration is not possible without dam removals. The approach being employed on the Penobscot River, where dams are being removed or provided the opportunity to increase power generation within a plan to provide increased access to habitat, offers a good model for restoration. Dammed Atlantic Coastal rivers offer a cautionary tale for developing nations intent on hydropower development, suggesting that lasting ecosystem-wide impacts cannot be compensated for through fish passage and hatchery technology.
Li, J., S. Dong, Z. Yang, M. Peng, S. Liu, X. Li, 2012: “Effects of cascade hydropower dams on the structure and distribution of riparian and upland vegetation along the middle-lower Lancang-Mekong River.” Forest Ecology and Management, v. 284, pp. 251-259, doi: 10.1016/j.foreco.2012.07.050.
The extensive number of hydropower dams being planned in southwest China has attracted much attention in recent years. Eight cascading dams along the middle and lower reaches of the Lancang-Mekong River basin were selected to assess the riparian and upland vegetation. A total of 24 transects and 126 quadrats perpendicular to the river channel were surveyed from upstream to downstream. By using two-way indicator species analysis (TWINSPAN), the vegetation types in this region were classified into 21 vegetation classes. The ecological gradient analysis was completed using canonical correspondence analysis (CCA) and demonstrated that the dominant environmental factors impacting vegetation distribution were the variations in latitude and altitude. The vegetation impact index (VII) was developed as a quantitative index to assess the impact of dam inundation and operation on the upland and riparian vegetation. The values of VII showed that the most endangered vegetation communities were the shrub and herb communities in riparian habitats along this river. The effects of cascading hydropower dams on riparian and upland vegetation distribution were more complex than those of single dams. Cascading hydropower dams can enhance habitat fragmentation, reduce the distribution ranges (latitude and altitude) of primary vegetation and reduce the complexity of the vegetation types along the river as well as induce the loss of primary vegetation in the whole watershed.
Zhai, H., B. Cui, B. Hu, and K. Zhang, 2010: “Prediction of river ecological integrity after cascade hydropower dam construction on the mainstream of rivers in Longitudinal Range-Gorge Region (LRGR), China.” Ecological Engineering, v. 36, no. 4, pp. 361-372, doi: 10.1016/j.ecoleng.2009.10.002.
Dam construction is considered the major factor contributing to significant modification of river ecosystems. The related ecological effects of these constructions on flow patterns, water quality, sediment etc. have led to increased concerns in recent years. Most of the works so far focus on the assessment of vulnerability, risk, and damages to single factors, such as soil conservation, fish reproduction or vegetation. Few works have been done on to analyzing and predicting the changes of the river ecosystem integrity (REI). Taking three important international rivers, Lancang River, Nu River and Yuan River in LRGR as a case study, the relationship between cascade dam construction and REI is analyzed. A model of the cascade dam construction and the REI is developed on Lancang River after cascade construction, and then it is applied on the Nu River and Yuan River to predict the changes of REI after the planned cascade construction. The results show that there are significant relationships between the cascade construction and the change of the REI. Before the cascade development, REI index of Nu River is the highest with a value of 0.844. Yuan River, the worst of the three before the cascade construction (0.719), is found to be the best one after the cascade construction (0.389). After the cascade construction, the REI index value of the Lancang River is likely to dramatically decrease from 0.825 to 0.274.
Boucher, M.-A., D. Tremblay, L. Delorme, L. Perreault, and F. Anctil, 2012: “Hydro-economic assessment of hydrological forecasting systems.” Journal of Hydrology, v. 416-417, pp. 133-144, doi: 10.1016/j.jhydrol.2011.11.042.
An increasing number of publications show that ensemble hydrological forecasts exhibit good performance when compared to observed streamflow. Many studies also conclude that ensemble forecasts lead to a better performance than deterministic ones. This investigation takes one step further by not only comparing ensemble and deterministic forecasts to observed values, but by employing the forecasts in a stochastic decision-making assistance tool for hydroelectricity production, during a flood event on the Gatineau River in Canada. This allows the comparison between different types of forecasts according to their value in terms of energy, spillage and storage in a reservoir. The motivation for this is to adopt the point of view of an end-user, here a hydroelectricity production society. We show that ensemble forecasts exhibit excellent performances when compared to observations and are also satisfying when involved in operation management for electricity production. Further improvement in terms of productivity can be reached through the use of a simple post-processing method.