R.E. Turner

TL;DR: In this paper, the authors pointed out that the formation of hypoxic areas has been exacerbated by any combination of interactions that increase primary production and accumulation of organic carbon leading to increased respiratory demand for oxygen below a seasonal or permanent pycnocline, and the consequences of eutrophication-induced hypoxia can be reversed if longterm, broad-scale, and persistent efforts to reduce substantial nutrient loads are developed and implemented.

TL;DR: In this article, the authors update and reevaluate the scientific information on the distribution, history, and causes of continental shelf hypoxia that supports the 2001 Action Plan for Reducing, Mitigating, and Controlling Hypoxia in the Northern Gulf of Mexico (Mississippi River/Gulf of Mexico Watershed Nutrient Task Force 2001).

TL;DR: This coastal ecosystem appears to be a pelagic food web dynamically poised to be either a food web composed of diatoms and copepods or one with potentially disruptive harmful algal blooms, directed between these two ecosystem states by Mississippi River water quality, which is determined by land-use practices far inland.

TL;DR: In this paper, the concentration of dissolved inorganic nitrogen (DIN), dissolved nitrate-N, Total-N (TN), DIP, total phosphorus (TP), dissolved silicate-Si (DSi) and their ratios in the world's largest rivers are examined using a global data base that includes 37% of the earth's watershed area and half its population.

TL;DR: Nitrogen, in particular nitrate+nitrite, and not phosphorus, dissolved silicate, or their molar ratios, appears to be the major driving factor influencing the size of the hypoxic zone on this shelf, consistent with cross-system analyses that conclude that the TN:TP ratio in the Mississippi River, currently fluctuating around 20:1, is indicative of nitrogen, not phosphorus.