4.4 Article

Global warming affects nutrient upwelling in deep lakes

Journal

AQUATIC SCIENCES
Volume 81, Issue 3, Pages -

Publisher

SPRINGER BASEL AG
DOI: 10.1007/s00027-019-0637-0

Keywords

Limnology; Climate change; Winter mixing; Phosphorus; Lake Zug

Funding

  1. Swiss National Science Foundation [200021_146652, 200020_165517]
  2. Amt fur Umweltschutz Zug
  3. Swiss National Science Foundation (SNF) [200021_146652, 200020_165517] Funding Source: Swiss National Science Foundation (SNF)

Ask authors/readers for more resources

Measures to reduce lake phosphorus concentrations have been encouragingly successful in many parts of the world. After significant eutrophication in the twentieth century, nutrient concentrations have declined in many natural settings. In addition to these direct anthropogenic impacts, however, climate change is also altering various processes in lakes. Its effects on lacustrine nutrient budgets remain poorly understood. Here we investigate the total phosphorus (TP) concentrations in the epilimnion of the meromictic Lake Zug under present and future climatic conditions. Results are compared with those of other deep lakes. Data showed that TP transported from the hypolimnion by convective winter mixing was the most important source of TP for the epilimnion, reaching values more than ten times higher than the external input from the catchment. We found a logarithmic relationship between winter mixing depth (WMD) and epilimnetic TP content in spring. Warming climate affects WMD mainly due to its dependence on autumn stratification. Model simulations predict a reduction of average WMD from 78 (current) to 65m in 2085 assuming IPCC scenario A2. Other scenarios show similar but smaller changes in the future. In scenario A2, climate change is predicted to reduce epilimnetic TP concentrations by up to 24% during warm winters and may consequently introduce significant year-to-year variability in primary productivity.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.4
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available