Collected Evidence: Collected Evidence: Remove oil from contaminated peatlands We found no studies that evaluated the effects, on peatland vegetation, of removing oil from contaminated peatlands. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1788https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1788Tue, 28 Nov 2017 08:17:28 +0000Collected Evidence: Collected Evidence: Remove pollutants from waste gases before they enter the environment One study evaluated the effects, on peatland vegetation, of removing pollutants from waste gases before release into the environment. The study was in bogs. Plant richness/diversity (1 study): One before-and-after study in bogs in Estonia reported that following installation of dust filters in industrial plants (along with a general reduction in emissions), the number of Sphagnum moss species increased but the total number of plant species decreased. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1789https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1789Tue, 28 Nov 2017 08:18:07 +0000Collected Evidence: Collected Evidence: Add lime to reduce acidity and/or increase fertility One study evaluated the effects of liming (without planting) on peatland vegetation. The study was in a fen meadow. N.B. Liming is considered in different contexts here and here. Vegetation structure (1 study): One replicated, controlled study in a fen meadow in the Netherlands found that liming increased overall vegetation biomass (mostly grass). Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1790https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1790Tue, 28 Nov 2017 08:18:28 +0000Collected Evidence: Collected Evidence: Drain/replace acidic water Two studies evaluated the effects on peatland vegetation of draining/replacing acidic surface water. Both studies were in fens. Vegetation cover (2 studies): Two controlled studies in fens in the Netherlands reported that draining acidic water had mixed effects on cover of Sphagnum moss and herbs after 4–5 years, depending on the species and whether moss was also removed. Overall plant richness/diversity (1 study): One controlled, before-and-after study in a fen in the Netherlands reported that draining and replacing acidic water increased plant species richness. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1791https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1791Tue, 28 Nov 2017 08:18:46 +0000Collected Evidence: Collected Evidence: Add water to peatlands to compensate for drought We found no studies that evaluated the effects, on peatland vegetation, of adding water to peatlands to compensate for drought. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1792https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1792Tue, 28 Nov 2017 08:19:08 +0000Collected Evidence: Collected Evidence: Plant shelter belts to protect peatlands from wind We found no studies that evaluated the effects, on peatland vegetation, of planting shelter belts to protect peatlands from wind. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1793https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1793Tue, 28 Nov 2017 08:19:25 +0000Collected Evidence: Collected Evidence: Build barriers to protect peatlands from the sea We found no studies that evaluated the effects, on peatland vegetation, of building barriers to protect peatlands from seawater damage. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1794https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1794Tue, 28 Nov 2017 08:19:42 +0000Collected Evidence: Collected Evidence: Restore/create peatlands in areas that will be climatically suitable in the future We found no studies that evaluated the effects, on peatland vegetation, of restoring or creating peatlands in areas that will be climatically suitable in the future. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1795https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1795Tue, 28 Nov 2017 08:21:18 +0000Collected Evidence: Collected Evidence: Legally protect peatlands Five studies evaluated the effects on peatland habitats of legally protecting them: two of tropical peat swamp forest, two of unspecified peatlands and one of a bog. Peatland habitat (3 studies): Two studies in Indonesia reported that peat swamp forest was lost from within the boundaries of national parks. However, one of these studies was a site comparison and reported that forest loss was greater outside the national park. One before-and-after study of peatlands in China reported that peatland area initially decreased, but then increased, following legal protection. Plant community composition (1 study): One before-and-after study in a bog in Denmark reported that the plant community compositon changed over 161 years of protection. In particular, woody plants became more abundant. Vegetation cover (1 study): One site comparison study in a peatland in Chile found that a protected area had greater vegetation cover (total, herbs and shrubs) than an adjacent grazed and moss-harvested area. Overall plant richness/diversity (2 studies): One before-and-after study in Denmark reported that the number of plant species in a protected bog fluctuated over time, with no clear trend. One site comparison study in a peatland in Chile found that a protected area had lower plant richness and diversity (but also fewer non-native species) than an adjacent grazed and harvested area. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1796https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1796Tue, 28 Nov 2017 08:26:41 +0000Collected Evidence: Collected Evidence: Create legislation for ‘no net loss’ of wetlands We found no studies that evaluated the effects, on peatland habitats, of creating legislation for no net loss of wetlands. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1797https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1797Tue, 28 Nov 2017 08:27:01 +0000Collected Evidence: Collected Evidence: Adopt voluntary agreements to protect peatlands We found no studies that evaluated the effects, on peatland habitats, of adopting voluntary agreements to protect them. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1798https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1798Tue, 28 Nov 2017 08:27:20 +0000Collected Evidence: Collected Evidence: Pay landowners to protect peatlands One study evaluated the effects on peatland habitats of paying landowners to protect them. The study was of bogs. Peatland habitat (1 study): One review from reported that agri-environment schemes in the UK had mixed effects on bogs, protecting the area of bog habitat in three of six cases. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1799https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1799Tue, 28 Nov 2017 08:27:33 +0000Collected Evidence: Collected Evidence: Increase ‘on-the-ground’ protection (e.g. rangers) One study evaluated the effects on peatland habitats of increasing ‘on-the-ground’ protection. The study was in tropical peat swamps. Behaviour change (1 study): One before-and-after study in a peat swamp forest in Indonesia reported that the number of illegal sawmills decreased over two years of anti-logging patrols. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1800https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1800Tue, 28 Nov 2017 08:27:48 +0000Collected Evidence: Collected Evidence: Allow sustainable use of peatlands We found no studies that evaluated the effects, on peatland habitats, of allowing sustainable use. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1801https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1801Tue, 28 Nov 2017 08:28:04 +0000Collected Evidence: Collected Evidence: Restore/create peatland vegetation (multiple interventions) Nine studies evaluated the effects of multiple restoration interventions (other than the moss layer transfer technique) on peatland vegetation. Six studies were in bogs (one being restored as a fen). One study was in a fen. Two studies were in unspecified or mixed peatlands. Plant community composition (3 studies): One replicated, controlled, before-and-after study in the UK reported that the overall plant community composition differed between restored and unrestored bogs. One replicated, controlled, site comparison study in Estonia found that restored and natural bogs contained more similar plant communities than unrestored and natural bogs. However, one site comparison study in Canada reported that after five years, bogs being restored as fens contained a different plant community to natural fens. Characteristic plants (1 study): One controlled study in a fen in France reported that restoration interventions increased cover of fen-characteristic plants. Moss cover (7 studies): Five studies (including one replicated, paired, controlled, before-and-after) in bogs or other peatlands in the UK, Estonia and Canada found that restoration interventions increased total moss (or bryophyte) cover. Two studies (one replicated and controlled) in bogs in the Czech Republic and Estonia reported that restoration interventions increased Sphagnum moss cover, but one replicated before-and-after study in bogs in the UK reported no change in Sphagnum cover following intervention. Two site comparison studies in Canada reported that after 1–15 years, restored areas had lower moss cover than natural fens. Herb cover (5 studies): Five studies (one replicated, paired, controlled, before-and-after) in bogs or other peatlands in the Czech Republic, the UK, Estonia and Canada reported that restoration interventions increased cover of herbaceous plants, including cottongrass and other grass-like plants. Overall vegetation cover (3 studies): Three studies (one replicated, controlled, before-and-after) in bogs in the UK and France reported that restoration interventions increased overall vegetation cover. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1803https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1803Tue, 28 Nov 2017 08:29:14 +0000Collected Evidence: Collected Evidence: Restore/create peatland vegetation using the moss layer transfer technique Four studies evaluated the effects, on peatland vegetation, of restoration using the moss layer transfer technique (as defined in the Background section). All four studies were based on bogs in Canada. Three studies were based on one experimental set-up that was included in the other, larger study. Plant community composition (2 studies): One replicated study in bogs in Canada reported that the majority of restored areas developed a community of bog-characteristic plant species within 11 years. One controlled, before-and-after study in a bog in Canada reported that a restored area (included in the previous study) developed a more peatland-characteristic plant community over time, and relative to an unrestored area. Vegetation cover (2 studies): Two controlled studies in one bog in Canada reported that a restored area had greater moss or bryophyte cover (including Sphagnum) than an unrestored area after 4–8 years. The restored area also had greater herb cover (including cottongrass), but less shrub cover, than the unrestored area. One of the studies reported that vegetation in the restored area became more similar to local natural bogs. Overall plant richness/diversity (1 study): One controlled, before-and-after study in a bog in Canada reported that a restored area contained more plant species than an unrestored area. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1804https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1804Tue, 28 Nov 2017 08:29:33 +0000Collected Evidence: Collected Evidence: Fill/block ditches to create conditions suitable for peatland plants (without planting) Three studies evaluated the effects of filling or blocking ditches (without planting) on peatland vegetation within them. Two studies were in bogs and one was in a fen. Vegetation cover (3 studies): Two studies in a bog in the UK and a fen in the USA reported that blocked or filled ditches were colonized by herbs and bryophytes within 2–3 years. In the USA, vegetation cover (total, bryophyte, forb, grass and sedge) was restored to natural, undisturbed levels. One replicated study in bogs in the UK reported that plants had not colonized blocked gullies after six months. Overall plant richness/diversity (1 study): One site comparison study in a fen in the USA found that a filled ditch contained more plant species than adjacent undisturbed fen, after two years. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1805https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1805Tue, 28 Nov 2017 08:29:55 +0000Collected Evidence: Collected Evidence: Excavate pools (without planting) Two studies evaluated the effects of excavating pools (without planting) on peatland vegetation. Both studies were based on the same experimental set-up in bogs in Canada. Plant community composition (1 study): One replicated, before-and-after, site comparison study in bogs in Canada reported that excavated pools were colonized by peatland vegetation over 4–6 years, but contained different plant communities to natural pools. In particular, cattail was more common in created pools. Vegetation cover (1 study): One replicated, before-and-after, site comparison study in bogs in Canada reported that after four years, created pools had less cover than natural pools of Sphagnum moss, herbs and shrubs. Overall plant richness/diversity (1 study): One replicated, before-and-after, site comparison study in bogs in Canada reported that after six years, created pools contained a similar number of plant species to natural pools. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1806https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1806Tue, 28 Nov 2017 08:30:10 +0000Collected Evidence: Collected Evidence: Reprofile/relandscape peatland (without planting) One study evaluated the effects of reprofiling/relandscaping peatlands (without planting) on peatland vegetation. The study was in degraded bogs (being restored as fens). Plant community composition (1 study): One site comparison study in Canada reported that after five years, reprofiled (and rewetted) bogs contained a different plant community to nearby natural fens. Vegetation cover (1 study): The same study reported that after five years, reprofiled (and rewetted) bogs had lower vegetation cover (Sphagnum moss, other moss and vascular plants) than nearby natural fens. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1807https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1807Tue, 28 Nov 2017 08:30:29 +0000Collected Evidence: Collected Evidence: Roughen peat surface to create microclimates (without planting) We found no studies that evaluated the effects, on peatland vegetation, of roughening the peat surface to create microclimates (without planting afterwards). ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1808https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1808Tue, 28 Nov 2017 08:30:48 +0000Collected Evidence: Collected Evidence: Remove upper layer of peat/soil (without planting) Ten studies evaluated the effects of removing the upper layer of peat or soil (without planting afterwards) on peatland vegetation. Nine studies were in fens or fen meadows and one was in an unspecified peatland. Plant community composition (6 studies): Five studies (including one replicated, randomized, paired, controlled) in a peatland in the USA and fens or fen meadows in the Netherlands and Poland reported that plots stripped of topsoil developed plant communities with a different composition to those in unstripped peatlands. In one study, the effect of stripping was not separated from the effect of rewetting. Two studies in fen meadows in Germany and Poland reported that the depth of soil stripping affected plant community development. Characteristic plants (5 studies): Four studies in fen meadows in Germany and the Netherlands, and a peatland in the USA, reported that stripping soil increased cover of wetland-characteristic or peatland-characteristic plants plants after 4–13 years. In the Netherlands, the effect of stripping was not separated from the effect of rewetting. One replicated site comparison study in fens in Belgium and the Netherlands found that stripping soil increased fen-characteristic plant richness. Herb cover (4 studies): Three studies (including one replicated, paired, controlled) in fens or fen meadows in Germany, the UK and Poland found that stripping soil increased cover of rushes, reeds or sedges after 2–6 years. However, one controlled study in a fen meadow in the Netherlands reported that stripping soil had no effect on sedge or bentgrass cover after five years. Two controlled studies in a fen meadow in the Netherlands and a fen in the UK found that stripping soil reduced purple moor grass cover for 2–5 years. Vegetation structure (3 studies): Two studies in fens or fen meadows in the Netherlands and Belgium found that stripping soil reduced vegetation biomass (total or herbs) for up to 18 years. One replicated, randomized, paired, controlled study in a peatland in the USA found that stripping soil had no effect on vegetation biomass after four years. Overall plant richness/diversity (6 studies): Three studies (including one replicated, paired, controlled) in fens or fen meadows in the UK, Belgium and the Netherlands reported that stripping soil increased total plant species richness over 2–18 years. In one study, the effect of stripping was not separated from the effect of rewetting. One replicated, controlled study in a fen in Poland found that stripping soil had no effect on plant species richness after three years. One replicated, randomized, paired, controlled study in a peatland in the USA found that stripping soil increased plant species richness and diversity, after four years, in one field but decreased it in another. One replicated study in a fen meadow in Poland reported that plant species richness increased over time, after stripping soil. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1809https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1809Tue, 28 Nov 2017 08:31:06 +0000Collected Evidence: Collected Evidence: Bury upper layer of peat/soil (without planting) We found no studies that evaluated the effects, on peatland vegetation, of burying the upper layer of peat or soil (without planting afterwards). ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1810https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1810Tue, 28 Nov 2017 08:31:22 +0000Collected Evidence: Collected Evidence: Disturb peatland surface to encourage growth of desirable plants (without planting) Two studies evaluated the effects of disturbing the peat surface (without planting) on peatland vegetation. Both studies were in fens. Plant community composition (2 studies): Two replicated, paired, controlled, before-and-after studies (one also randomized) in fens in Germany and Sweden reported that soil disturbance affected development of the plant community over 2–3 years. In Germany, disturbed plots developed greater cover of weedy species from the seed bank than undisturbed plots. In Sweden, the community in disturbed and undisturbed plots became less similar over time.  Characteristic plants (2 studies): The same two studies reported that wetland- or fen-characteristic plant species colonized plots that had been disrturbed (along with other interventions). The study in Germany noted that peat-forming species did not colonize the fen. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1811https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1811Tue, 28 Nov 2017 08:31:40 +0000Collected Evidence: Collected Evidence: Add inorganic fertilizer (without planting) Three studies evaluated the effects of adding inorganic fertilizer (without planting) on peatland vegetation. Two studies were in bogs and one was in a fen meadow. Vegetation cover (1 study): One replicated, randomized, paired, controlled, before-and-after study in a bog in New Zealand reported that fertilizing typically increased total vegetation cover. Vegetation structure (1 study): One replicated, paired, controlled study in a fen meadow in the Netherlands found that fertilizing with phosphorous typically increased total above-ground vegetation biomass, but other chemicals typically had no effect. Overall plant richness/diversity (1 study): One replicated, randomized, paired, controlled, before-and-after study in a bog in New Zealand reported that fertilizing typically increased plant species richness. Growth (1 study): One replicated, controlled, before-and-after study in a bog in Germany found that fertilizing with phosphorous typically increased herb and shrub growth rate, but other chemicals had no effect. Other (3 studies): Three replicated, controlled studies in a fen meadow in Germany and bogs in Germany and New Zealand reported that effects of fertilizer on peatland were more common when phosphorous was added, than when nitrogen or potassium were added. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1812https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1812Tue, 28 Nov 2017 08:37:10 +0000Collected Evidence: Collected Evidence: Cover peatland with organic mulch (without planting) Two studies evaluated the effects, on peatland vegetation, of covering a peatland with organic mulch (without planting). Both studies were in bogs (but in one study, being restored as a fen). Vegetation cover (2 studies): One replicated, randomized, paired, controlled, before-and-after study in a bog in Canada found that covering bare peat with straw mulch did not affect cover of fen-characteristic plants. One replicated, controlled, before-and-after study in a bog in Australia reported that plots mulched with straw had similar Sphagnum moss cover to unmulched plots. Characteristic plants (1 study): One replicated, randomized, paired, controlled, before-and-after study in a bog in Canada found that covering bare peat with straw mulch increased the number of fen characteristic plants present, but did not affect their cover. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1813https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1813Tue, 28 Nov 2017 08:38:22 +0000
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What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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