Atmospheric nitrogen deposition has caused nitrogen enrichment and eutrophication of lakes in the northern hemisphere

Abstract

We compiled chemical data and phytoplankton biomass (PB) data (chlorophyll a) from unproductive lakes in 42 different regions in Europe and North America, and compared these data to inorganic nitrogen (N) deposition over these regions. We demonstrate that increased deposition of inorganic N over large areas of Europe and North America has caused elevated concentrations of inorganic N in lakes. In addition, the unproductive lakes in high N deposition areas had clearly higher PB relative to the total phosphorus (P) concentrations illustrating that the elevated inorganic N concentrations has resulted in eutrophication and increased biomass of phytoplankton. The eutrophication caused by inorganic N deposition indicates that PB yield in a majority of lakes in the northern hemisphere is (was) limited by N in their natural state. We, therefore, suggest that P limitation largely concerns lakes where the balance between N and P has been changed because of increased anthropogenic input of N.

Land-use change, not climate, controls organic carbon burial in lakes

“…Disruption of the global N cycle is now comparable to alteration of the carbon cycle [31], and there is increasing evidence for direct effects of atmospheric N deposition on lakes [32]. A positive effect on algal productivity due to increased atmospheric nitrogen inputs for the western Great Lakes region was postulated by Axler et al [33].…”

“…Moreover, the P surplus documented in agricultural soils worldwide [42] has considerable long-term implications for carbon burial in aquatic ecosystems. Also, while P induced eutrophication is a major problem for lakes in more developed regions [8], the effect of atmospherically transported reactive N on remote lakes is unlikely to diminish in the immediate future [30,32]. Overall, it is probable that nutrient transfer from land to surface waters will maintain elevated levels of lake productivity and C burial in the short term [8].…”

Evaluating anthropogenic N inputs to diverse lake basins: A case study of three Chinese lakes

“…Despite their differences, all three lakes have suffered from serious N pollution (Liu et al 2009;Frumin and Khuan 2012). The relationship between nutrient concentrations and eutrophication of lakes has been a debate for decades, focusing on whether N or P is the limiting factor for eutrophication (Paerl et al 2004;Bergström and Jansson 2006;Schindler et al 2008;Conley et al 2009;Scott and McCarthy 2010). Generally, nutrient limitation for eutrophication of lakes is a case-specific question, depending on various factors such as temperature (Moss et al 2013), N deposition (Elser et al 2009), lake age (Moss et al 2013), and nutrient loading (Paerl et al 2011).…”

Consequence of altered nitrogen cycles in the coupled human and ecological system under changing climate: The need for long-term and site-based research

“…In both N-and P-limited tundra ecosystems, C fluxes were found to respond positively to additions of both elements, although responses to P tended to be stronger than to N (Shaver et al 1998). Bergström and Jansson (2006) have shown that increased N deposition may have changed lakes from N-limitation to P-limitation in remote and small lakes across the northern hemisphere, an observation supported by nutrient addition experiments in UK upland streams (Maberly et al 2002). On the other hand, an assessment of long-term data from a Spanish ILTER lake site by Camarero and Catalan (2012) suggested that atmospheric P deposition may cause lakes to revert from P-limitation to N-limitation.…”