Nelson the total large river systems globally. In addition,

Nelson et al. present a global overview of dam-based impacts on large river systems (LRS) to show that out of 292 global LRSs they studied, 172 have been significantly affected by dams. Their emphasis rests specifically on the impact of these damming on the flow pattern and channel fragmentation in these river systems by using collected data on the total virgin mean annual discharge (VMAD) as a parameter to classify these LRSs as either unaffected, moderately affected or strongly affected. The results in figure 1 show that strongly affected river systems constitute more than 50 percent of the total large river systems globally. In addition, the boxplot in figure 4 clearly shows the economic driving force of the impact such that the gross LRS product associated with national economies of unaffected river systems is 25 times lower than that of moderately and strongly affected LRS.What this demonstrates, I think, is how manipulative and destructive we are on our natural resources for our own greed for hydropower and economic development with little consideration on how the resulting ecological risks would affect the biodiversity of these natural ecosystems. Of course, every country needs to build on sustainable energy source to capitalize their economic development. But the question on energy demand should not only be about whether these countries need electricity for their growth and industrialization, and whether this energy should come from hydropower. Instead, the question really should be on how these damming projects have been moved forward against existing laws and regulations with little or non-existent attention on the long-term environmental and social impacts. Looking at figure 1 closely, we begin to see not only the severity of the impact but also the spread on all the major rivers in the world. If this was the pattern nearly one and half decades ago and the construction of such water infrastructures never stopped, then what would today’s pattern be like? How many more large river systems could be left untouched by these developmental projects? Well, the answers to these questions could definitely be more red spread out across the globe which means the water security threat became intensified and hardly any large river system is left unaffected.Furthermore, the ecological impacts on the river ecosystems are irreversibly consequential. Unfortunately, our decision makers such as the government and corporate representatives often think too short of the cost-benefit analysis and are tempted to follow specific interests to move forward with these projects. I think this best explains why local resistance is increasingly becoming a viable alternative that is getting better coordinated worldwide.¬†Questions:Thinking locally, what trade-offs do you think are involved that resulted in no dams on our Fraser river? Why do you think it’s important for the deciding parties to consider such compromises?Besides resistance, what other alternatives do you think are potentially important in the fight against large construction projects – both locally and internationally?


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