Impacts of Nutrient Reduction on Coastal Communities

Abstract

Eutrophication due to high anthropogenic nutrient loading has greatly impacted ecological processes in marine coastal waters and, therefore, much effort has been put into reducing nitrogen and phosphorus discharges into European and North-American waters. Nutrient enrichment usually resulted in increase of biomass and production of phytoplankton and microphytobenthos, often coinciding with shifts in species composition within the primary producer community. Consequences of increasing eutrophication for higher trophic levels are still being disputed, and even less is known about the consequences of nutrient reduction on coastal food webs. Here, we present 30-year concurrent field observations on phytoplankton, macrozoobenthos and estuarine birds in the Dutch Wadden Sea, which has been subject to decades of nutrient enrichment and subsequent nutrient reduction. We demonstrate that long-term varia-

Long-term variability of winter nitrate concentrations in the Northern Wadden Sea driven by freshwater discharge, decreasing riverine loads and denitrification

“…Cadée (1986a, b) observed an increase in primary production and a proliferation of the colony forming flagellate Phaeocystis globosa. The increase in primary production continued until the mid 1990s and since then a decreasing trend is observed (Cadée and Hegeman 2002;Philippart et al 2007). Especially, the Phaeocystis blooms were considered as negative effects of eutrophication because of the large amounts of foam that were formed after the collapse of these blooms (Lancelot et al 1987).…”

Nutrient and chlorophyll a anomaly in red-tide periods of 2003–2008 in Sishili Bay, China

“…Aquaculture and nutrients input can also influence phytoplankton (Cadee and Hegeman, 2002;Philippart et al, 2007); for example, cultured scallops can strongly reduce chl-a concentrations (Dame et al, 1991;Phelps, 1994;Kohata et al, 2003). As one of the most intensive culture areas in China, Sishili Bay is influenced by cultured organisms, such as scallops and kelp Cadee and Hegeman, 2002;Zhou et al, 2002b).…”

“…The rapid progress of aquiculture and the circumlittoral economy have greatly influenced coastal environments in China, resulting in ecological imbalance, decreased biodiversity, and rapid reduction of biological resources in estuaries and coastal bays (Turner and Rabalais, 1994;Poder et al, 2003;Philippart et al, 2007). Anthropogenic nutrient loading from terrestrial systems usually causes eutrophication and increased occurrence of red tides.…”

How phosphorus limitation can control climate-active gas sources and sinks

“…As a result, these coastal marine ecosystems undergo eutrophication (Cloern, 2001). However, due to management policies aiming at reducing eutrophication (implementation of wastewater treatment and banishment of P-based detergents), phosphorus (P) loads decreased after the mid-80's in several coastal ecosystems, while nitrogen (N) loads remained generally high because of continued use of artificial fertilizers in agriculture (Cadée and Hegeman, 2002;Loebl et al, 2009;Philippart et al, 2007). Consequently, phytoplankton growth in these coastal areas is now limited by P availability (e.g.…”

“…Consequently, phytoplankton growth in these coastal areas is now limited by P availability (e.g. Harrison et al, 1990;Philippart et al, 2007;Rabalais et al, 2002;Trommer et al, 2013;Ly et al, 2014).…”