Temporary wetland restoration after rice cultivation: is soil transfer required for aquatic plant colonization?

• Published in: Knowledge and management of aquatic ecosystems 2013-01, Vol.411, p.17-17
• Main Authors: Muller, I, Buisson, E, Mouronval, J B, Mesleard, F
• Format: Article
• Language: English
• Subjects: Freshwater
• ISSN: 1961-9502; 1961-9502

Mediterranean temporary wetlands have considerably declined in recent decades. Today, opportunities arise for the restoration of these wetlands due to land-use changes, such as the abandonment of cultivation. One critical question is whether communities, such as those observed in natural temporary wetlands, can develop alone or if active restoration should be implemented. In a series of experimental mesocosms, we transferred soil from several temporary wetlands chosen as a set of reference ecosystems. Four months after soil transfer, vegetation in transfer mesocosms was compared to that derived from spontaneous colonization (control mesocoms). Transfer mesocosms are colonized by all target hydrophyte species transferred with the soil and the resulting communities are similar to those of reference ecosystems. They also have fewer non-target species than the control mesocosms. Even though the study period was not sufficient to draw any definitive conclusion regarding the utility of forced dispersion by soil transfer, the preliminary results are promising for an application on a larger scale.Original Abstract: Les marais temporaires mediterraneens ont vu leur superficie se reduire considerablement au cours des dernieres decennies. Aujourd'hui, des opportunites apparaissent pour la restauration de ces zones humides, en particulier a partir d'espaces agricoles abandonnes. L'une des questions majeures est alors de savoir si les communautes telles que l'on peut les observer dans les marais temporaires naturels peuvent se developper seules ou si une restauration active doit etre mise en place. Dans un ensemble de mesocosmes experimentaux, nous avons transfere du sol provenant de plusieurs marais temporaires choisis comme un ensemble d'ecosystemes de reference. Quatre mois apres le transfert de sol, la vegetation des mesocosmes transferes a ete comparee a celle issue uniquement de la colonisation spontanee (temoins). Les mesocosmes ayant subi un transfert de sol sont colonises par la totalite des hydrophytes cibles transferees par le sol et presentent des communautes similaires a celles des ecosystemes de reference. Ils presentent d'autre part moins d'especes jugees indesirables que les mesocosmes temoins. Meme si la duree de l'etude ne nous permet pas de conclure definitivement sur la necessite d'operer un forcage de dispersion par transfert de sol, ces resultats preliminaires sont prometteurs pour une application a plus large echelle.