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1.
Ecological restoration is expected to reverse the loss of biodiversity and ecosystem services. Due to the low number of well‐replicated field studies, the extent to which restoration recovers plant communities, and the factors underlying possible shortcomings, are not well understood even in medium term. We compared the plant community composition of 38 sites comprising pristine, forestry‐drained, and 5 or 10 years ago restored peatlands in southern Finland, with special interest in understanding spatial variation within studied sites, as well as the development of the numbers and the abundances of target species. Our results indicated a recovery of community composition 5–10 years after restoration, but there was significant heterogeneity in recovery. Plant communities farthest away from ditches were very similar to their pristine reference already 10 years after restoration. In contrast, communities in the ditches were as far from the target as the drained communities. The recovery appears to be characterized by a decline in the number and abundance of species typical to degraded conditions, and increase in the abundance of characteristic peatland species. However, we found no increase above the drained state in the number of characteristic peatland species. Our results suggest that there is a risk of drawing premature conclusions on the efficiency of ecological restoration with the current practice of short‐term monitoring. Our results also illustrate fine‐scale within‐site spatial variability in the degradation and recovery of the plant communities that should be considered when evaluating the success of restoration. Overall, we find the heterogeneous outcome of restoration observed here promising. However, low recovery in the number of characteristic species demonstrates the importance of prioritizing restoration sites, and addressing the uncertainty of recovery when setting restoration targets. It appears that it is easier to eradicate unwanted species than regain characteristic species by restoration.  相似文献   

2.
We studied the effects of restoration on water‐table depth (WTD), element concentrations of peat and vegetation composition of peatlands drained for forestry in southern Finland. The restoration aimed to return the trajectory of vegetation succession toward that of undisturbed systems through the blockage of ditches and the removal of trees. Permanent plots established on a bog and a fen were sampled 1 year before, and 1, 2, 3, and 10 years after the restoration. The restoration resulted in a long‐term rise of the water‐table in both peatlands. Ten years after restoration, the mineral element concentrations (Ca, K, Mg, Mn, and P) of peat corresponded to those reported from comparable pristine peatlands. In particular, the increase of K and Mn concentrations at both sites suggests the recovery of ecosystem functionality in terms of nutrient cycling between peat and plants. The restoration resulted in the succession of plant communities toward the targeted peatland vegetation of wetter condition at both sites. This was evident from the decreased abundance of species benefiting from drainage and the corresponding increase of peatland species. However, many species typical of pristine peatlands were missing 10 years after restoration. We conclude that the restoration led to a reversal of the effects of drainage in vegetation and studied habitat conditions. However, due to the slow recovery of peatland ecosystems and the possibility that certain failures in the restoration measures may become apparent only after extended time periods, long‐term monitoring is needed to determine whether the goals of restoration will be met.  相似文献   

3.
Drainage and afforestation of peatlands cause extensive habitat degradation and species losses. Restoration supports peatland biodiversity by creating suitable habitat conditions, including stable high water tables. However, colonization by characteristic species can take decades or even fail. Peatland recovery is often monitored shortly after restoration, but initial trends may not continue, and results might differ among taxonomic groups. This study analyzes trends in plant, dragonfly, and butterfly diversity within 18 years after rewetting of montane peatlands in central Germany. We compared diversity and species composition of 19 restored sites with three drained peatlands and one near‐natural reference site. Restoration resulted in improved habitat conditions and benefited species diversity, but there were marked differences among taxonomic groups. Dragonflies rapidly colonized small water bodies but their diversity did not further increase in older restoration sites. Characteristic peatland vegetation recovered slowly, since it depended on a high water holding capacity that was only reached after peat started accumulating. Generally, plant diversity developed toward reference conditions albeit incompletely, even 18 years after restoration. Butterflies responded less to peatland restoration; generalists increased only temporarily and specialists could not establish. In conclusion, peatland restoration improves habitat conditions and biodiversity, while trajectories of recovery are nonlinear and incomplete after two decades. This highlights the need for long‐term monitoring and a strategic selection of indicator species for evaluation of restoration success.  相似文献   

4.
The aim of the study was to assess the effects of fen rewetting on carabid beetle and vascular plant assemblages within riverine fens along the river Peene in north‐eastern Germany. Drained (silage grassland), rewetted (restored formerly drained silage grassland), and near‐natural (fairly pristine) stands were compared. Eighty‐four beetle species (7,267 individuals) and 135 plant species were recorded. The richness of vascular plant species and the number of endangered species were highest on near‐natural fens. Fourteen years of rewetting did not increase plant species numbers compared with drained fens. For carabid beetles, however, species richness and the number of stenotopic species were highest on rewetted fens. Rewetting caused the replacement of generalist carabids by wetland specialists, but did not provide suitable habitat for specialist fen carabids or for plant species of oligo‐ or mesotrophic fen communities. Therefore, raising the water table on fens with nutrient‐rich, degraded peat was not sufficient for restoring species assemblages of intact fens, although water level was the most important environmental factor separating species assemblages. Our study illustrated that insects and plants may respond differentially to restoration, stressing the need to consider different taxa when assessing the efficiency of fen restoration. Furthermore, species assemblages of intact fens could not be restored within 14 years, highlighting the importance of conserving pristine habitat.  相似文献   

5.
Mire degradation due to drainage for forestry results in the loss of mire specialist species. To halt the loss in biodiversity, ecological restoration is needed and already implemented. However, a major challenge in ecological restoration is whether actions taken have the desired outcome. Key abiotic and biotic conditions for the successful restoration of invertebrate communities can be identified by testing the “Field of Dreams” hypothesis, which postulates that if a habitat is successfully restored, species will return. This study was conducted in nine boreal mires located in Eastern Finland, 1–3 years after restoration. Parts of each mire were drained for forestry during the 1960s and 1970s, and restored in 2003–2006. Two 250 m transects were established in each of three treatments (pristine, drained, restored) per mire. We used pitfall trapping to sample carabid beetles and spiders, sweep netting to sample micromoths and crane flies and counts along the transects to sample macromoths. Vegetation cover, water table level, and climatic variables were measured along all transects. Mire specialist species and invertebrate communities responded positively to restoration and negatively to drainage, whereas generalists showed varied responses. In addition, mire specialists were associated with high cover of Sphagnum mosses and with low numbers of tall trees (>3 m). Therefore, to successfully restore populations and communities of mire specialist invertebrates, maintaining environmental conditions that favor the growth of Sphagnum mosses, rewetting the sites and removing larger trees are necessary measures.  相似文献   

6.
Peatlands represent globally-important ecosystems and carbon stores. However, large areas of peatland have been drained for agriculture, or peat has been harvested for use as fuel or in horticulture. Increasingly, these landscapes are being restored through ditch blocking and rewetting primarily to improve biodiversity and promote peat accumulation. To date we have little knowledge of how these interventions influence the microbial communities in peatlands. We compared the responses of dominant microbial consumers (testate amoebae) to drainage ditch restoration relative to unblocked ditches in a UK upland blanket peatland (Migneint, North Wales). Two techniques were used for restoration: (i) dammed ditches with re-profiling; and (ii) dammed ditches with pools of open water behind each dam. Testate communities in the inter-ditch areas changed markedly over time and between treatments illustrating the potential of this group of organisms as indicators of blanket peatland restoration status. However, the responses of testate amoebae to peat rewetting associated with restoration were partially obscured by inter-annual variability in weather conditions through the course of the experiment. Although there was considerable variability in the response of testate amoebae communities to peatland drain blocking, there were clearly more pronounced changes in samples from the dammed and reprofiled treatments including an increase in diversity, and the appearance of unambiguous wet-indicator species in relatively high abundances (including Amphitrema stenostoma, Archerella flavum, Arcella discoides type, Difflugia bacillifera and Difflugia bacillarium). This reflects a shift towards overall wetter conditions across the site and the creation of new habitats. However, water-table was not a significant control on testate amoebae in this case, suggesting a poor relationship between water table and surface moisture in this sloping blanket peatland. Our findings highlight the potential of testate amoebae as bioindicators of peatland restoration success; however, there is a need for caution as mechanisms driving change in the microbial communities may be more complex than first assumed. Several factors need to be taken into account when implementing biomonitoring studies in peatlands including: (i) the natural variability of the peatland ecosystem under changing weather conditions; (ii) any disturbance connected with the restoration procedures; and (iii) the timescales over which the ecosystem responds to the management intervention. Our results also suggest an indicator species approach based on population dynamics may be more appropriate for biomonitoring peatland restoration than examining changes at the community level.  相似文献   

7.
Growing public interest in conserving peatlands has created a need for restoration and rapid indicators of progress in peat formation. Vegetation and hydrological indicators are commonly assessed, but changes in mineralization and decomposition rates might better indicate when peat formation is underway in restored peatlands. In Finland, we investigated differences in mineralization and decomposition in the upper peat layer of five undrained and eight drained Pinus‐dominated fens from 2006 to 2009. Forestry‐drained fens were restored in 2007 by harvesting either whole trees or only stems, and by damming and filling ditches. Before restoration, net N mineralization rate was slightly higher in the drained than in undrained fens, whereas soil pH and Betula leaf litter decomposition rate were lower. After restoration, net N mineralization rate was similar for the undrained and restored fens, except near ditches after stem harvest. Also, soil pH and decomposition rate of Betula leaf litter became similar for undrained and restored fens. We conclude that whole tree harvest is a more suitable method for peatland restoration than stem harvest and that mineralization and decomposition rates are suitable indicators for peat formation after restoration.  相似文献   

8.
Developing objective tools for tracking progress of restored sites is of general concern. Here, we present an innovative approach based on principal response curves (PRC) and species classification according to their preferential habitats to monitor changes in community composition. Following large‐scale restoration of a cut‐over peatland, vegetation was surveyed biannually over 8 years. We evaluated whether the establishing plant communities fell within the range of natural variation. We used both general diversity curves and PRC applied on plant species grouped by preferred habitat to compare restored sites and unrestored sites to a reference ecosystem. After 8 years, diversity and richness differed between the sites, with Forest and Ruderal species more prominent in unrestored sites, and Peatland, Forest, and Wetland species dominant in restored sites. The PRC revealed that the restored site became rapidly dominated by typical peatland plants, the main drivers of temporal changes being Sphagnum rubellum, Pohlia nutans, and Mylia anomala. Some differences remained between the restored and the undisturbed species pools: the former had more herbaceous species associated with wetlands such as Calamagrostis canadensis and Typha latifolia and the latter had more forested species like Kalmia angustifolia throughout the study. PRC revealed to be an efficient tool identifying species driving changes at the community level after restoration. In our case study, examining PRC scores after classifying species according to their preferred habitat allowed to illustrate objectively how restoration promotes target species (associated to peatlands) and how lack of intervention benefits ruderal species.  相似文献   

9.
Many peatlands were affected by drainage in the past, and restoration of their water regime aims to bring back their original functions. The purpose of our study was to simulate re-wetting of soils of different types of drained peatlands (bogs and minerotrophic mires, located in the Sumava Mountains, Czech Republic) under laboratory conditions (incubation for 15 weeks) and to assess possible risks of peatland water regime restoration - especially nutrient leaching and the potentials for CO2 and CH4 production. After re-wetting of soils sampled from drained peatlands (simulated by anaerobic incubation) (i) phosphorus concentration (SRP) did not change in any soil, (ii) concentration of ammonium and dissolved organic nitrogen (DON) increased, but only in a drained fen, (iii) DOC increased significantly in the drained fen and degraded drained bog, (iv) CO2 production decreased, (v) CH4 production and the number of methanogens increased in all soils, and (vi) archaeal methanogenic community composition was also affected by re-wetting; it differed significantly between drained and pristine fens, whereas it was more similar between drained and pristine bogs. Overall, the soils from fens reacted more dynamically to re-wetting than the bogs, and therefore, some nutrients (especially nitrogen) and DOC leaching may be expected from drained fens after their water regime restoration. However, if compared to their state before restoration, ammonium and phosphorus leaching should not increase and leaching of nitrates and DON should even decrease after restoration, especially during the vegetation season. Further, CO2 production in soils of fens and bogs should decrease after their water regime restoration, whereas CH4 production in soils should increase. However, we cannot derive any clear conclusions about CH4 emissions from the ecosystems based on this study, as they depend strongly on environmental factors and on the actual activity of methanotrophs in situ.  相似文献   

10.
Ecological restoration of mined peatlands in North America involves active reintroduction of bog plant species. Animals are not actively reintroduced, thus the re‐establishment of peatland fauna must occur either by inoculation along with introduced plant material or by dispersal. We examined the extent to which insects are reintroduced to restored sites with plant material by rearing insects from shredded vegetation collected in three donor sites. We assessed differences in abundance, diversity, and composition of taxonomic and trophic groups among seasons and sites. Abundance and species richness did not differ by season, but species assemblages did. The three sites were significantly different in abundance, but not in species richness and assemblages. Few insects emerged from the vegetation, suggesting that shredded plant material may not be the primary source of insect colonists. Insects likely recolonize by active or passive dispersal from the surrounding area. The species pool was similar among donor sites; consequently a mined site could be inoculated with vegetation from another peatland in the same region and this would not affect the insect assemblages at the initial stage of establishment. Diapause may be a major factor for emergence success among seasons of collection. Knowledge of how restoration techniques influence establishment of insect communities will help predict longer‐term outcomes of restoration on biotic communities in peatlands.  相似文献   

11.
Generalist species are becoming increasingly dominant in European bird communities. This has been taken as evidence of biotic homogenization, whereby generalist ‘winners’ systematically replace specialist ‘losers’. We test this pattern by relating changes in the average specialization of UK bird communities to changes in the density of species with different degrees of habitat specialization. Although we find the expected decline in community specialization, this was driven by a combination of a strong increase in the density of the most generalist quartile of species and declines in the density of moderately generalist species. Contrary to expectation, specialist species increased slightly over the 18‐year study period but had little effect on the overall trend in community specialization. Our results indicate that the apparent homogenization of UK bird communities is not driven by the replacement of specialists by generalists, but instead by the changing fortunes of generalist species.  相似文献   

12.
The natural recovery of vegetation on abandoned peat extraction areas lasts for decades and the result of restoration succession can be unpredictable. The aim of the study was to specify environmental factors that affect the formation of the pioneer stages of mire communities and, therefore, be helpful in the prediction of the resulting ecosystem properties. We used the national inventory data from 64 milled peatlands in Estonia, distributed over the region of 300 × 200 km. This is the first national‐scale statistical evaluation of abandoned extracted peatlands. During surveys, vascular plants, bryophytes, and residual peat properties were recorded on three microtopographic forms: flats, ditch margins, and ditches. The microtopography was the main factor distinguishing the composition of plant communities on flats and ditches, while ditch margins resembled flats. The extracted indicator species suggested two successional pathways, toward fen or raised bog community. A single indicator trait—the depth of residual peat, which combines the information about peat properties (e.g. pH, ash content, and trophicity status), predicted the plant community succession in microtopographic habitats. We suggest that peatland management plans about the cost‐efficient restoration of abandoned peat mining areas should consider properties of residual peat layer as the baseline indicator: milled peatfields with thin (<2.3 m) and well‐decomposed residual peat should be restored toward fen vegetation types, whereas sites with thick (>2.3 m) and less decomposed residual peat layer should be restored toward transitional mires or raised bogs. Specific methodological suggestions are provided .  相似文献   

13.
Ecological restoration is considered to play an important role in mitigating climate change, protecting biodiversity, and preventing environmental degradation. Yet, there are often multiple perspectives on what outcomes restoration should be aiming to achieve, and how we should get to that point. In this study we interview a range of policymakers, academics, and non‐governmental organization (NGO) representatives to explore the range of perspectives on the restoration of Indonesia's tropical peatlands—key global ecosystems that have undergone large‐scale degradation. Thematic analysis suggests that participants agreed about the importance of restoration, but had differing opinions on how effective restoration activities to date have been and what a restored peatland landscape should look like. These results exemplify how ecological restoration can mean different things to different people, but also highlight important areas of consensus for moving forward with peatland restoration strategies.  相似文献   

14.
Assessing the community‐level consequences of ecological restoration treatments is essential to guide future restoration efforts. We compared the vegetation composition and species richness of restored sites that received a range of restoration treatments and those of unrestored sites that experienced varying levels of disturbance. Our study was conducted in the industrially degraded landscape surrounding Sudbury, Ontario, Canada. The Great Lakes–St. Lawrence Forest once present in this area was degraded through logging, mining, and smelting activities beginning in the late 1800s until restoration of the most visibly degraded areas began in 1974. Restoration treatments ranged from simple abiotic enhancements to complex, multistage revegetation treatments using native and non‐native species, which included fertilizing, spreading of ground dolomitic limestone, understory seeding, and tree planting. Canonical correspondence analysis was used to determine which restoration treatments explained differences in the community structure among sites. We found that native understory vascular species richness was similar in restored sites that received more complex restoration treatments and unrestored sites that were mildly disturbed; however, the role of planted trees and non‐native species in the restored communities remains unclear. Understory vascular seeding played a key role in determining community composition of vascular understory and overstory communities, but the time since restoration commenced was a more important factor for nonvascular communities because they received no direct biotic enhancements. The use of non‐native species in the vascular seed mix seems to be slowly encouraging the colonization of native species, but non‐natives continue to dominate restored sites 25 years after restoration began.  相似文献   

15.
As most ecosystems, peatlands have been heavily exploited for different human purposes. For example, in Finland the majority is under forestry, agriculture or peat mining use. Peatlands play an important role in carbon storage, water cycle, and are a unique habitat for rare organisms. Such properties highlight their environmental importance and the need for their restoration. To monitor the success of peatland restoration sensitive indicators are needed. Here we test whether testate amoebae can be used as a reliable bioindicator for assessing peatland condition. To qualify as reliable indicators, responses in testate amoebae community structure to ecological changes must be stronger than random spatial and temporal variation. In this study, we simultaneously assessed differences between the effects of seasonality, intermediate scale spatial variation and land uses on living testate amoebae assemblages in natural, forested and restored peatlands. We expected the effects of seasonality on testate amoebae communities to be less pronounced than those of land use and within site variation. On average, natural sites harboured the highest richness and density, while the lowest numbers were found at forestry sites. Despite small changes observed in taxa dominance and differences in TA community structure between seasons and years at some sites, spatial heterogeneity, temperature, pH, nor water table depth seemed to significantly affect testate amoebae communities. Instead, observed differences were related to type of land use, which explained 75% of the community variation. Our results showed that testate amoebae community monitoring is a useful tool to evaluate impacts of human land use on boreal peatlands.  相似文献   

16.
17.
Status and restoration of peatlands in northern Europe   总被引:3,自引:0,他引:3  
Vasander  H.  Tuittila  E.-S.  Lode  E.  Lundin  L.  Ilomets  M.  Sallantaus  T.  Heikkilä  R.  Pitkänen  M.-L.  Laine  J. 《Wetlands Ecology and Management》2003,11(1-2):51-63
Environmental management of peatlands,landscape ecology and protection of keybiotopes have created needs and pressure torestore drained peatlands to natural mireecosystems. Here, we summarize differentapproaches and restoration techniquesdeveloped for peatland management inEstonia, Sweden, and Finland wherepeatlands are abundant. Without rewetting,plant colonisation on abandoned cut-awayareas is slow due to harsh hydrological andmicroclimatic conditions. However, after restoration, cut-away peatlands may returnto a functional state close to that ofpristine mires, and therefore restore a netcarbon sink function within a few years. Inaddition, restoration techniques can helpto create buffer zones between terrestrialand limnic ecosystems that reduces thenutrient loading imposed on watercourses byforestry operations. Restoration may alsobe important for peatland conservationprograms as drained peatlands are part ofpresent and future conservation areas.Finally, restoration actions in themselvescan have negative environmental impacts.For instance, inundation of peat surfacesresulting from the rewetting process oftenincreases phosphorus leaching. Efforts onpeatland restoration should focus onenvironmental monitoring, research onrestoration and its environmental impact aswell as public relations activities. Inthat respect, knowledge transfer betweenacademics and managers should generatesynergy benefits.  相似文献   

18.
Achieving high intraspecific genetic diversity is a critical goal in ecological restoration as it increases the adaptive potential and long‐term resilience of populations. Thus, we investigated genetic diversity within and between pristine sites in a fossil floodplain and compared it to sites restored by hay transfer between 1997 and 2014. RAD‐seq genotyping revealed that the stenoecious floodplain species Arabis nemorensis is co‐occurring with individuals that, based on ploidy, ITS‐sequencing and morphology, probably belong to the close relative Arabis sagittata, which has a documented preference for dry calcareous grasslands but has not been reported in floodplain meadows. We show that hay transfer maintains genetic diversity for both species. Additionally, in A. sagittata, transfer from multiple genetically isolated pristine sites resulted in restored sites with increased diversity and admixed local genotypes. In A. nemorensis, transfer did not create novel admixture dynamics because genetic diversity between pristine sites was less differentiated. Thus, the effects of hay transfer on genetic diversity also depend on the genetic make‐up of the donor communities of each species, especially when local material is mixed. Our results demonstrate the efficiency of hay transfer for habitat restoration and emphasize the importance of prerestoration characterization of microgeographic patterns of intraspecific diversity of the community to guarantee that restoration practices reach their goal, that is maximize the adaptive potential of the entire restored plant community. Overlooking these patterns may alter the balance between species in the community. Additionally, our comparison of summary statistics obtained from de novo‐ and reference‐based RAD‐seq pipelines shows that the genomic impact of restoration can be reliably monitored in species lacking prior genomic knowledge.  相似文献   

19.
Tropical ecosystems are globally important for bird diversity. In many tropical regions, land‐use intensification has caused conversion of natural forests into human‐modified habitats, such as secondary forests and heterogeneous agricultural landscapes. Despite previous research, the distribution of bird communities in these forest‐farmland mosaics is not well understood. To achieve a comprehensive understanding of bird diversity and community turnover in a human‐modified Kenyan landscape, we recorded bird communities at 20 sites covering the complete habitat gradient from forest (near natural forest, secondary forest) to farmland (subsistence farmland, sugarcane plantation) using point counts and distance sampling. Bird density and species richness were on average higher in farmland than in forest habitats. Within forest and farmland, bird density and species richness increased with vegetation structural diversity, i.e., were higher in near natural than in secondary forest and in subsistence farmland than in sugarcane plantations. Bird communities in forest and farmland habitats were very distinct and very few forest specialists occurred in farmland habitats. Moreover, insectivorous bird species declined in farmland habitats whereas carnivores and herbivores increased. Our study confirms that tropical farmlands can hardly accommodate forest specialist species. Contrary to most previous studies, our findings show that structurally rich tropical farmlands hold a surprisingly rich and distinct bird community that is threatened by conversion of subsistence farmland into sugarcane plantations. We conclude that conservation strategies in the tropics must go beyond rain forest protection and should integrate structurally heterogeneous agroecosystems into conservation plans that aim at maintaining the diverse bird communities of tropical forest‐farmland mosaics.  相似文献   

20.
Indonesia declared an ambitious plan to restore its degraded and fire‐prone peatlands, which have been a source of significant greenhouse gas and haze. However, the progress has been slow and the plan cannot succeed without sustained social supports and political will. Although many previous studies argued for the need to see ecological restoration in socio‐economic contexts, empirical assessments have been lacking for how restoration is operationalized on the ground. We interviewed 47 key informants involved in four different projects in Central Kalimantan, Indonesia, and assessed their definitions, goals, and practices of peatland restoration. Most of the actors we interviewed defined peatland restoration primarily in an ecological context following the global concept of ecological restoration. However, all four restoration projects were designed without determining reference and trajectory conditions. Their intermediate goals and practices were more focused on engaging local communities and developing sustainable livelihood options than improving the ecological conditions of peatlands. To be internally consistent, peatland restoration needs to recognize a social dimension in its process, as well as in its goal. Setting clear trajectory conditions is also important to clarify achievable goals and measurable intermediate outcomes. We propose the following definition of peatland restoration: a process of assisting the recovery of degraded peatland ecosystems to achieve the appropriate trajectories defined through multi‐stakeholder collaboration within social‐ecological contexts. We hope to generate healthy debates to further refine the definition that encompasses both social and ecological dimensions to generate broader support for sustaining and expanding peatland restoration projects in Indonesia.  相似文献   

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