Association is not causation: treatment effects cannot be estimated from observational data in heart failure

Estuarine ecosystems are increasingly threatened by coastal development and climate change. The large number of estuaries globally necessitates risk assessment to prioritise conservation efforts. Schemes for assessing risk of ecosystem collapse have been designed around terrestrial ecosystems, often defined by a single characteristic vegetation type, with their applicability to estuaries unclear. Here we consider the causes and symptoms of...