Proximate and underlying drivers of wetland conversion.

<p>Proximate and underlying drivers of wetland conversion.</p

Probability of conversion of wetland areas and converted and non-converted wetland sites (data set 4).

<p>Grey areas are non-wetland areas. Wetland areas are defined based on the Global Lakes and Wetland Database [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0081292#B27" target="_blank">27</a>].</p

Sites of wetland conversion.

<p>In green wetland areas (including lakes and areas with partial wetland cover) from the Global Lakes and Wetland Database (from Lehner and Döll, [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0081292#B27" target="_blank">27</a>]).</p

Number of times underlying forces of wetland conversion are documented in the 105 analyzed case-studies.

<p>Number of times underlying forces of wetland conversion are documented in the 105 analyzed case-studies.</p

Number of times proximate causes of wetland conversion are documented in the 105 analyzed case-studies.

<p>Number of times proximate causes of wetland conversion are documented in the 105 analyzed case-studies.</p

Most frequent occurring combinations of proximate causes and underlying forces of wetland conversion.

<p>Agricultural development includes pasture expansion. For each proximate cause at least the two most important underlying forces are indicated, and for each underlying force at least two associated proximate causes indicated.</p

Appendix C. The equations used to solve the linear dynamics as well as the biomass and relative growth rate values for each trophic group in each year.

The equations used to solve the linear dynamics as well as the biomass and relative growth rate values for each trophic group in each year

Appendix A. A description of the input parameters needed to create an ECOPATH mass balance, their units, and empirical relations necessary to calculate them.

A description of the input parameters needed to create an ECOPATH mass balance, their units, and empirical relations necessary to calculate them

Appendix B. A list of the sources of all parameters used for each trophic group in each mass balance, including primary parameters used in empirical relations as well as input and output parameters used for the mass balance.

A list of the sources of all parameters used for each trophic group in each mass balance, including primary parameters used in empirical relations as well as input and output parameters used for the mass balance

DataSheet1.ZIP

<p>Submerged macrophytes play a key role in north temperate shallow lakes by stabilizing clear-water conditions. Eutrophication has resulted in macrophyte loss and shifts to turbid conditions in many lakes. Considerable efforts have been devoted to shallow lake restoration in many countries, but long-term success depends on a stable recovery of submerged macrophytes. However, recovery patterns vary widely and remain to be fully understood. We hypothesize that reduced external nutrient loading leads to an intermediate recovery state with clear spring and turbid summer conditions similar to the pattern described for eutrophication. In contrast, lake internal restoration measures can result in transient clear-water conditions both in spring and summer and reversals to turbid conditions. Furthermore, we hypothesize that these contrasting restoration measures result in different macrophyte species composition, with added implications for seasonal dynamics due to differences in plant traits. To test these hypotheses, we analyzed data on water quality and submerged macrophytes from 49 north temperate shallow lakes that were in a turbid state and subjected to restoration measures. To study the dynamics of macrophytes during nutrient load reduction, we adapted the ecosystem model PCLake. Our survey and model simulations revealed the existence of an intermediate recovery state upon reduced external nutrient loading, characterized by spring clear-water phases and turbid summers, whereas internal lake restoration measures often resulted in clear-water conditions in spring and summer with returns to turbid conditions after some years. External and internal lake restoration measures resulted in different macrophyte communities. The intermediate recovery state following reduced nutrient loading is characterized by a few macrophyte species (mainly pondweeds) that can resist wave action allowing survival in shallow areas, germinate early in spring, have energy-rich vegetative propagules facilitating rapid initial growth and that can complete their life cycle by early summer. Later in the growing season these plants are, according to our simulations, outcompeted by periphyton, leading to late-summer phytoplankton blooms. Internal lake restoration measures often coincide with a rapid but transient colonization by hornworts, waterweeds or charophytes. Stable clear-water conditions and a diverse macrophyte flora only occurred decades after external nutrient load reduction or when measures were combined.</p