Cut‐over peatland regeneration assessment using organic matter and microbial indicators (bacteria and testate amoebae)

Abstract

Summary 1.Cut-over peatlands cover large surfaces of high potential value for enhancing biodiversity and carbon sequestration if successfully restored. Unfortunately, evaluation of restoration success is not straightforward. We assessed the bioindicator value of organic matter (OM), testate amoebae (protozoa) and bacteria in peat from two regeneration stages and a reference site of a cut-over bog. 2. Contrasting biochemical signatures of peat OM were observed along the regenerating profiles, allowing clear differentiation between the newly regenerated peat and the old peat. Where peat macrofossils were absent sugar biomarkers were used to infer peat botanical origin and OM alteration. 3. Over the succession, the OM composition of the new peat differed. Peat from the more recent stage was dominated by Sphagnum -derived tissues and characterized by lower carbohydrate preservation and higher bacterial biomass than the advanced regeneration stage. 4. Surface testate amoeba communities also changed from the recent to the advanced stages of regeneration, indicating a shift from wet and moderately acidic conditions to drier and more acidic conditions. Over this regeneration sequence (i) the biomass and average size of species declined but were higher at the unexploited site and (ii) species richness and diversity increased but density declined. Synthesis and applications.Although secondary succession in the cut-over bog led to an ecosystem similar to that of the reference site in terms of surface vegetation, OM and testate amoebae continued to reflect disturbances associated with peat harvesting. Nevertheless, the described dynamics of both microbial and biochemical variables over the succession showed similarities between the advanced stage and the reference site: a higher testate amoeba diversity was associated with better carbohydrate preservation and a more heterogeneous botanical composition of the peat. The inferred water table depth and pH based on testate amoebae indicators proved to be an alternative approach for assessing restoration processes, in contrast to labour-intensive repeated measurements in the field. The botanical and biochemical composition of peat OM provided additional information on past anthropogenic perturbations of the bog and could be used for restoration monitoring. The combination of several indicators therefore provides a more complete assessment of ecological conditions that could be valuable for the management of cut-over peatlands.

Effects of vegetation restoration on soil organic carbon sequestration at multiple scales in semi-arid Loess Plateau, China

“…This assessment is of a multi-attribute analysis with SOC as one of the important indicators for ecological process or ecosystem function (Laggoun-Défarge et al, 2008;RuizJaen and Aide, 2005). We can conclude from the present study that vegetation restoration can significantly enhance the SOC stock of surface soil (0-20 cm).…”

Comparative ecology of vascular plant, bryophyte and testate amoeba communities in four Sphagnum peatlands along an altitudinal gradient in Switzerland

“…However, these two taxa may respond to site history (e.g. peat harvesting and subsequent revitalization, Buttler et al, 1996;Laggoun-Défarge et al, 2008) as much if not more than to differences in climate, soil moisture or nutrient content.…”

How many is enough? Determining optimal count totals for ecological and palaeoecological studies of testate amoebae

“…By analysing testate amoeba community changes down the length of a core and interpreting the results with a transfer function model, it is possible to quantitatively reconstruct changing mire surface wetness (Booth et al 2004;Lamentowicz et al 2008;Sillasoo et al 2007;Woodland et al 1998) as well as sea-levels (Gehrels et al 2001;Roe et al 2002) through the Holocene. Testate amoebae are also used over shorter time periods to monitor the success of peatland restoration (Buttler et al 1996;Davis and Wilkinson 2004;Jauhiainen 2002;Laggoun-Défarge et al 2008;Vickery and Charman 2004) and the impact of pollution in aquatic or terrestrial ecosystems (Balik 1991;Kandeler et al 1992; Kauppila et al 2006;Kumar and Patterson 2000;Nguyen-Viet et al 2007Patterson et al 1996;Patterson and Kumar 2002;Reinhardt et al 1998;Scott et al 2001;Török 2001).…”