Estimates of early-industrial inputs of nutrients to river systems: implication for coastal eutrophication

Changes in nutrient loads (N, P and Si) in the São Francisco estuary after the construction of dams

“…With the increase in world population growth, with 45% of the total population inhabiting coastal regions, there has been increased demand for water, electric power and territorial space, resulting in multiple environmental impacts and altering the natural flows of water and matterials (Milliman and Meade, 1983;Meybeck, 1993;Crossland et al, 2005). Some of these impacts are often coupled to the construction of dams, which retain suspended sediments and transform the composition of nutrients in their reservoirs, changing their flows to the coastal region (Halim, 1991;Billen et al, 1999;Vörösmarty et al, 2003;Beusen et al, 2005;Syvitski et al, 2005). Knowledge on the composition and temporal variation of a river's nutrient load allows for inferences to be made about the nature of the human impact on the drainage basin and its effects on the coastal region, and also serves to underpin the implementation of management actions to mitigate the impacts (Crossland et al, 2005).…”

Trophic Conditions in the Waters of the Venice Lagoon (Northern Adriatic Sea, Italy)

“…In fact, over the last four decades, human activities increased nitrogen fluxes into many coastal areas [1] affecting the ecosystem equilibrium. In Europe, the problem was mostly observed in the North Sea [2,3] and along the occidental and southern coastal areas [4]. The open waters of the Mediterranean Sea are considered to be generally good and are classified among the poorest in nutrients of the world oceans [5].…”

Distribution, fluxes and decadal changes of nutrients in the Jiulong River Estuary, Southwest Taiwan Strait

“…Decadal increases in nutrients of nitrogen and phosphorus, along with decreases in dissolved silicate (DSi) concentration, have been widely reported in many large river basins in the world [1,2]. This could be a consequence of either global climate change or growing human activities (e.g.…”

“…These changes have made significant environmental impacts on coastal ecosystems [1,8], e.g. coastal eutrophication, frequent harmful algal bloom events, and seasonal hypoxia [1,[9][10][11].…”

“…coastal eutrophication, frequent harmful algal bloom events, and seasonal hypoxia [1,[9][10][11]. Therefore, variation in riverine fluxes of nutrients has been highlighted over the past 30 years, and is a major theme in the Land-Ocean Interactions in the Coastal Zone (LOICZ) program [8].…”