Nitrification Control by Plants and Preference for Ammonium versus Nitrate: Positive Feedbacks Increase Productivity but Undermine Resilience.

AbstractSome plants, via their action on microorganisms, control soil nitrification (i.e., the transformation of ammonium into nitrate).

Evolutionary emergence of alternative stable states in shallow lakes.

Ecosystems under stress may respond abruptly and irreversibly through tipping points. Although mechanisms leading to alternative stable states are much studied, little is known about how such ecosystems could have emerged in the first place. We investigate whether evolution by natural selection along resource gradients leads to bistability, using shallow lakes as an example.