Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Cut/remove/thin forest plantations Four studies evaluated the effect on peatland vegetation of cutting/removing forest plantations: one in bogs and three in fens. The studies in the fens were all based, at least in part, on the same experimental set-up. Herb cover (3 studies): Three replicated studies (two also paired and controlled) in bogs in the UK and fens in Sweden reported that tree removal increased cover of some herb species including cottongrasses and sedges. One of the studies reported no effect of tree removal on other herb species. Moss cover (3 studies): One replicated, paired, controlled study in bogs in the UK reported that tree removal reduced cover of forest-characteristic mosses. One replicated before-and-after study in a drained rich fen in Sweden reported that Sphagnum moss cover decreased over three years following tree removal. However, one replicated, paired, controlled study in partly rewetted rich fens reported that Sphagnum cover increased over eight years following tree removal. Overall plant richness/diversity (2 studies): Two replicated, paired, controlled studies in rich fens in Sweden reported that tree removal increased total plant species richness. However, one of these studies reported a much smaller effect of tree removal in rewetted plots than in drained plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1731https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1731Mon, 27 Nov 2017 21:16:28 +0000Collected Evidence: Collected Evidence: Cut/remove/thin forest plantations and rewet peat Eleven studies evaluated the effects of cutting/removing trees and rewetting peat (in combination): six in fens, two in bogs, and three in both fens and bogs. In four of the studies, the peatlands naturally contained some trees. Three studies were based on one experimental set-up, and two studies were based on another. Plant community composition (5 studies): Of three replicated studies in fens, two in Finland found that removing trees/rewetting had no effect on the overall plant community composition whilst one in Sweden reported only a small effect. Two site comparison studies in bogs and fens in Finland found that removing trees/rewetting changed the overall plant community composition. It became less like sites that remained drained and forested. Characteristic plants (2 studies): Two before-and-after studies (one site comparison, one controlled) in bogs and fens in Finland and Sweden reported that removing trees/rewetting increased the abundance of wetland-characteristic plants. Moss cover (6 studies): Of five studies that examined the effect of removing trees/rewetting on Sphagnum moss, two replicated, paired studies in bogs and fens in Sweden and Finland found that the intervention increased Sphagnum cover. One replicated, before-and-after, site comparison study in forested fens in Finland found no effect. Two before-and-after studies in a bog in Finland and a fen in Sweden found mixed effects depending on site or species. Additionally, three studies (two replicated and paired) in peatlands in the UK and Finland found that removing trees/rewetting reduced cover of non-Sphagnum or forest-characteristic mosses. However, one replicated, before-and-after, site comparison study in forested fens in Finland found no effect of thinning trees/rewetting on forest mosses. Herb cover (7 studies): Seven studies (including two replicated, paired, controlled) in bogs and fens in the UK, Finland and Sweden reported that removing trees/rewetting increased cover of at least one group of herbs, including cottongrasses and sedges. However, one of these studies reported loss of cottongrass from a fen where it was rare before intervention, along with reduced purple moor grass cover. Vegetation structure (4 studies): One replicated site comparison study in a bog in the UK found that removing trees/rewetting increased ground vegetation height. One replicated, paired, controlled study in a fen in Sweden reported that removing trees/rewetting had no effect on canopy height after eight years. Two replicated, paired, site comparison studies in bogs and fens in Finland found that thinning trees/rewetting reduced the number of tall trees present for 1–3 years (although not to the level of natural peatlands). Overall plant richness/diversity (4 studies): Two replicated, paired, controlled studies in rich fens in Sweden reported that removing trees/rewetting increased plant species richness. However, two replicated studies in fens in Finland found that removing trees/rewetting had no effect on total plant species richness or diversity. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1732https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1732Mon, 27 Nov 2017 21:16:46 +0000Collected Evidence: Collected Evidence: Exclude or remove livestock from degraded peatlands Ten studies evaluated the effects on peatland vegetation of excluding or removing livestock from degraded peatlands. Seven studies were in bogs, two in fens and one in an unspecified peatland. Three studies were based on the same experimental set-up in the UK. Plant community composition (2 studies): Of two replicated, paired, controlled studies in bogs in the UK, one found that excluding sheep had no effect on the development of the plant community. The other found no effect in wetter areas of the bog, but that in drier areas excluding sheep favoured dry moorland plants. Herb cover (9 studies): Seven studies (including six replicated, paired, controlled) in bogs in the UK and Australia and fens in the USA found that excluding or removing livestock typically had no effect on cover of key herb groups. Five of five studies found that excluding livestock typically had no effect on cottongrass cover. Two of two studies reported no effect on sedge cover. However, one before-and-after study in a poor fen in Spain reported that rush cover increased after cattle were excluded (along with other interventions). One site comparison study in Chile found that excluding livestock (along with other interventions) increased overall herb cover, but one replicated, paired, controlled study in bogs in Australia found that excluding livestock had no effect on overall herb cover. Moss cover (6 studies): Five replicated, paired, controlled studies in bogs in the UK and Australia found that excluding livestock typically had no effect on Sphagnum moss cover. Responses sometimes varied between species and sites. Three of the studies in the UK also found no effect on cover of other mosses. One before-and-after study in a poor fen in Spain reported that Sphagnum moss appeared after excluding cattle (and rewetting). Tree/shrub cover (8 studies): Four replicated, paired, controlled studies in bogs in the UK and Australia found that excluding livestock had no effect on shrub cover (specifically heather or a heathland community). One replicated, paired, controlled study in a bog in the UK found that excluding sheep had no effect on heather cover in wetter areas, but increased heather cover in drier areas. Three studies (including two site comparisons) in bogs in the UK, fens in the USA and a peatland in Chile found that excluding or removing livestock increased shrub cover. Vegetation structure (1 study): One replicated, paired, controlled study in a bog in the UK found that excluding sheep increased total vegetation, shrub and bryophyte biomass but had no effect on biomass of grass-like herbs. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1734https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1734Mon, 27 Nov 2017 21:21:00 +0000Collected Evidence: Collected Evidence: Rewet peatland (raise water table) Thirty-six studies evaluated the effects of rewetting (without planting) on peatland vegetation. Fifteen studies were in bogs (two being restored as fens). Fifteen studies were in fens or fen meadows (two were naturally forested). Six studies were in general or unspecified peatlands. Some studies were based on the same experimental set-up or sites as each other: two studies in Germany, three studies in Sweden, two studies in west Finland and two studies in south Finland. Plant community composition (13 studies): Six before-and-after studies (four also replicated) in peatlands in Finland, Hungary, Sweden, Poland and Germany reported changes in the overall plant community composition following rewetting. Typically, drier grassland communities were replaced by more wetland- or peatland-characteristic communities. One replicated, paired, controlled study in a bog in the Czech Republic found that rewetted plots developed a different plant community to drained plots. Three site comparison studies in Finland and Canada reported that rewetted peatlands contained a different plant community to natural peatlands. Three replicated studies in peatlands in the UK and fens in Germany reported that rewetting typically had no effect, or insignificant effects, on the plant community. Characteristic plants (11 studies): Five studies (including one replicated site comparison) in peatlands in Canada, the UK, China and Poland reported that rewetting (sometimes along with other interventions) increased the abundance of wetland- or peatland-characteristic plants. Two replicated site comparison studies in fens or fen meadows in central Europe found that rewetting reduced the number of fen-characteristic plant species. Two studies (one replicated, paired, controlled, before-and-after) in fens in Sweden reported that rewetting had no effect on cover of fen-characteristic plants. Two before-and-after studies in fens in the USA and New Zealand reported that upland plant cover decreased following rewetting. Moss cover (19 studies): Twelve studies (five replicated, two also paired and controlled) in the UK, Ireland, Germany, Sweden, Latvia, Canada and Spain reported that rewetting bogs, fens or other peatlands (sometimes along with other interventions) increased Sphagnum moss cover or abundance. Three of these studies reported mixed responses by species. Two additional replicated studies, in bogs in Latvia and forested fens in Finland, reported that rewetting had no effect on Sphagnum cover. Five studies (one paired, controlled, before-and-after) in Finland, Sweden and Canada reported that rewetting bogs or fens had no effect on cover of non-Sphagnum mosses (or mosses/lichens). However, two controlled studies in bogs in Ireland and the UK reported that rewetting reduced cover of non-Sphagnum mosses or bryophytes. One site comparison study in Finland reported that a rewetted peatland had similar moss cover (Sphagnum and total) to a natural peatland, but another site comparison study in Canada reported that a rewetted bog had lower moss cover (Sphagnum and other) than nearby target peatlands. Herb cover (25 studies): Twenty-one studies (including four replicated, paired, controlled) reported that rewetting (sometimes along with other interventions) increased cover of at least one group of herbs. These studies were in bogs, fens or other peatlands in the UK, Finland, Ireland, the Czech Republic, the USA, the Netherlands, Sweden, Germany, China, Latvia, Poland, Canada and Spain. Specifically, rewetting increased other/total sedge cover in 13 of 15 studies, increased cottongrass cover in eight of nine studies, and increased reed/rush cover in five of seven studies. Three of four before-and-after studies in peatlands in the UK and Sweden reported that rewetting reduced purple moor grass cover; the other study reported no effect. One replicated site comparison study in forested fens in Finland reported that rewetting had no effect on total herb cover. Two site comparison studies in Europe reported greater herb cover in rewetted than natural peatlands (overall and sedges/rushes, but not forbs). Tree/shrub cover (13 studies): Ten studies (including two paired and controlled) in peatlands in Finland, the UK, Germany, Latvia and Canada reported that rewetting typically reduced (seven studies) or had no effect (six studies) on tree and/or shrub cover. Two before-and-after studies in fens in Sweden and Germany reported that rewetting increased tree/shrub cover. One before-and-after study in a bog in the UK reported mixed effects of rewetting on different tree/shrub species. Overall vegetation cover (4 studies): Of four before-and-after studies (three also controlled) that examined the effect of rewetting on overall vegetation cover, two in bogs in Ireland and Sweden reported that rewetting increased it. One study in a fen in New Zealand reported that rewetting reduced vegetation cover. One study in a peatland in Finland reported no effect. Overall plant richness/diversity (14 studies): Six studies (including one replicated, paired, controlled, before-and-after) in Sweden, Germany and the UK reported that rewetting increased total plant species richness or diversity in bogs, fens or other peatlands. However, five studies found no effect: in bogs in the Czech Republic and Latvia, fens in Sweden and Germany, and forested fens in Finland. One study in fen meadows in the Netherlands found scale-dependent effects. One paired, controlled, before-and-after study in a peatland in Finland reported that rewetting reduced plant diversity. Of four studies that compared rewetted and natural peatlands, two in Finland and Germany reported lower species richness in rewetted peatlands, one in Sweden found higher species richness in rewetted fens, and one in Europe found similar richness in rewetted and natural fens. Growth (1 study): One replicated site comparison study in forested fens in Finland found that rewetting increased Sphagnum moss growth to natural levels. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1756https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1756Mon, 27 Nov 2017 21:33:59 +0000Collected Evidence: Collected Evidence: Cut/mow herbaceous plants to maintain or restore disturbance Fourteen studies evaluated the effects on peatland vegetation of cutting/mowing to maintain or restore disturbance. All 14 studies were in fens or fen meadows. Most studies examined the effect of annual mowing regimes, but three examined the effect of single cuts. N.B. Cutting/mowing in peatlands with no history of disturbance is considered as a separate action. Plant community composition (7 studies): Six replicated studies in fens and fen meadows in the UK, Belgium, Germany and the Czech Republic reported that mowing altered the overall plant community composition (compared to no mowing, before mowing or grazing). One site comparison study in Poland reported that mowing a degraded fen (along with other interventions) made the plant community more similar to a target fen meadow. Characteristic plants (5 studies): Four studies (including one replicated, paired, controlled, before-and-after) in fens and fen meadows in Switzerland, Germany, the Czech Republic and Poland found that cutting/mowing increased cover of fen- or wet meadow-characteristic plants. One replicated before-and-after study in fens in the UK found that a single mow typically had no effect on cover of fen-characteristic plants. In Poland and the UK, the effect of mowing was not separated from the effects of other interventions. Moss cover (6 studies): Of six studies (five replicated, paired, controlled) in fens or fen meadows, four in Belgium, Switzerland and the Czech Republic found that mowing increased total moss or bryophyte cover. Two studies in Poland and the UK found that a single mow typically had no effect on bryophyte cover (total or hollow-adapted mosses). Herb cover (8 studies): Six replicated studies (three also randomized and controlled) in fens and fen meadows in Belgium, Germany, Poland and the UK found that mowing reduced cover or abundance of at least one group of herbs (including bindweed, reeds, sedges, purple moor grass and grass-like plants overall). One before-and-after study in a fen in Poland found that mowing (along with other interventions) increased sedge cover. One replicated, randomized, paired, controlled study in fen meadows in Switzerland found that mowing had no effect on overall herb cover. Tree/shrub cover (3 studies): Of three replicated studies in fens, two in the UK found that a single mow (sometimes along with other interventions) reduced shrub cover. However, one study in Poland found that a single mow had no effect on shrub cover. Vegetation structure (7 studies): In the following studies, vegetation structure was measured 6–12 months after the most recent cut/mow. Three replicated studies in fens in Poland and the UK reported that a single mow (sometimes along with other interventions) had no, or no consistent, effect on vegetation height. One replicated, paired, site comparison study in fen meadows in Switzerland found that mowing reduced vegetation height. Three studies (including two replicated, paired, site comparisons) in fen meadows in Switzerland, Poland and Italy found mixed effects of mowing on vegetation biomass (total, sedge/rush, moss or common reed). One replicated, paired, site comparison study in Germany reported that mown fen meadows had similar vegetation structure to grazed meadows. Overall plant richness/diversity (11 studies): Eight studies in fens and fen meadows in the UK, Belgium, Switzerland, Germany, the Czech Republic and Poland found that mowing/cutting increased plant species richness (compared to no mowing, before mowing or grazing). Three studies (including two replicated, randomized, paired, controlled) in fens in Poland and the UK found that a single mow (sometimes along with other interventions) typically had no effect on plant species richness and/or diversity. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1759https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1759Mon, 27 Nov 2017 21:35:31 +0000Collected Evidence: Collected Evidence: Use grazing to maintain or restore disturbance Four studies evaluated the effects, on peatland vegetation, of using grazing to maintain or restore disturbance. All four studies were in fens or fen meadows. N.B. Grazing in peatlands with no history of disturbance is considered as a separate action. Plant community composition (1 study): One replicated, paired, site comparison study in Germany found that the overall plant community composition differed between grazed and mown fen meadows. Characteristic plants (3 studies): One replicated, paired, controlled study in Germany reported that the abundance of bog/fen-characteristic plants was similar in grazed and ungrazed fen meadows. One replicated before-and-after study in a fen in the UK reported that cover of fen-characteristic mosses did not change after grazers were introduced. One replicated, paired, site comparison study, also in Germany, found that grazed fen meadows contained fewer fen-characteristic plant species than mown meadows. Herb cover (2 studies): Two before-and-after studies in fens in the UK reported that grazing increased cover of some herb groups (cottongrasses, sedges or all grass-like plants). One of the studies found that grazing reduced purple moor grass cover, but the other found that grazing typically had no effect. Moss cover (2 studies): One replicated before-and-after study in a fen in the UK reported that cover of fen-characteristic mosses did not change after grazers were introduced. One controlled, before-and-after study in a fen in the UK found that grazing reduced Sphagnum moss cover. Tree/shrub cover (2 studies): Of two before-and-after studies in fens in the UK, one found that grazing reduced shrub cover but the other found that grazing typically had no effect on shrub cover. Overall plant richness/diversity (3 studies): Of two before-and-after studies in fens in the UK, one found that plant species richness increased after grazing was reinstated but the other reported that there was typically no effect. One replicated, paired, site comparison study in Germany found that grazed fen meadows contained fewer plant species than mown meadows. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1762https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1762Mon, 27 Nov 2017 21:36:40 +0000Collected Evidence: Collected Evidence: Use cutting/mowing to control problematic herbaceous plants Four studies evaluated the effects on peatland vegetation of cutting/mowing problematic herbaceous plants. Three studies were in fens or fen meadows and one was in a bog. N.B. Cutting/mowing in historically disturbed peatlands is considered as a separate action. Plant community composition (3 studies): Two replicated, randomized, paired, controlled, before-and-after studies in rich fens in Sweden found that mowing typically had no significant effect on the overall plant community composition. One controlled study in a fen meadow in the UK reported that mown plots developed different plant communities to unmown plots. Characteristic plants (1 study): One replicated, randomized, paired, controlled, before-and-after study in a fen in Sweden found that mown plots contained more fen-characteristic plant species than unmown plots, although their cover did not differ significantly between treatments. Vegetation cover (2 studies): Of two replicated, randomized, paired, controlled, before-and-after studies in rich fens in Sweden, one found that mowing had no effect on vascular plant or bryophyte cover over five years. The other reported that mowing typically increased Sphagnum moss cover and reduced purple moor grass cover, but had mixed effects on cover of other plant species. Growth (1 study): One replicated, controlled, before-and-after study in a bog in Estonia found that clipping competing vegetation did not affect Sphagnum moss growth. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1770https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1770Mon, 27 Nov 2017 21:42:11 +0000Collected Evidence: Collected Evidence: Use prescribed fire to control problematic plants Six studies evaluated the effects on peatland vegetation of using prescribed fire to control problematic plants: five in bogs and one in fens. Four studies were based on the same experimental set-up in the UK. N.B. Prescribed burning in historically disturbed peatlands is considered as a separate action. Moss cover (4 studies): One replicated, paired, controlled study in bogs in Germany found that burning increased moss/lichen/bare ground cover in the short term (2–7 months after burning). Three replicated, paired studies (based on the same experimental set-up) in one bog in the UK found that moss cover (including Sphagnum) was higher in plots burned more often. Herb cover (4 studies): Of two replicated, paired, controlled studies in bogs in Germany and the UK, one found that burning had no effect on cottongrass cover after 2–7 months but the other found that burning increased cottongrass cover after 8–18 years. Two replicated, paired studies in the same bog in the UK reported that cottongrass cover was similar in plots burned every 10 or 20 years. The study in Germany also found that burning reduced purple moor grass cover but had mixed effects, amongst sites, on cover of other grass-like plants and forbs. Tree/shrub cover (5 studies): Three replicated, paired studies in a bog in the UK found that heather cover was lower in plots burned more often. One replicated, paired, controlled study in bogs in Germany found that heather cover was lower in burned than unburned plots. Two replicated, controlled studies in the bogs in Germany and fens in the USA found that burning (sometimes along with other interventions) did not affect cover of other shrubs. Vegetation structure (1 study): One replicated, paired, controlled study in a bog in the UK found that plots burned more frequently contained more biomass of grass-like plants than plots burned less often, but contained less total vegetation, shrub and bryophyte biomass. Overall plant richness/diversity (2 studies): Two replicated, controlled studies (one also randomized and paired) in the fens in the USA and a bog in the UK found that burning reduced or limited plant species richness. In the USA, burning was carried out along with other interventions. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1774https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1774Mon, 27 Nov 2017 21:43:40 +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: 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: 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: Directly plant peatland mosses Seven studies evaluated the effects on peatland vegetation of planting mosses. Six studies were in bogs and one was in a fen. Survival (1 study): One study in Lithuania reported that of 50 Sphagnum-dominated sods planted into a rewetted bog, 47 survived for one year. Growth (2 studies): Two before-and-after studies in a fen in the Netherlands and bog pools in the UK reported that mosses grew after planting. Moss cover (5 studies): Five before-and-after studies in a fen in the Netherlands and bogs in Germany, Ireland, Estonia and Australia reported that after planting mosses, the area covered by moss increased in at least some cases. The study in the Netherlands reported spread of planted moss beyond the introduction site. The study in Australia was also controlled and reported that planted plots developed greater Sphagnum moss cover than unplanted plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1818https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1818Tue, 28 Nov 2017 08:44:34 +0000Collected Evidence: Collected Evidence: Directly plant peatland herbs Five studies evaluated the effects on peatland vegetation of planting herbaceous plants. Three studies were in fens or fen meadows and two were in bogs. Survival (3 studies): Three replicated studies in a fen meadow in the Netherlands and fens in the USA reported that planted herbs survived over 2–3 years. However, for six of nine species only a minority of individuals survived. Growth (2 studies): Two replicated before-and-after studies in a bog in Germany and fens in the USA reported that individual planted herbs grew. Vegetation cover (1 study): One replicated, controlled, before-and-after study in Canada found that planting herbs had no effect on moss, herb or shrub cover in created bog pools relative to natural colonization. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1819https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1819Tue, 28 Nov 2017 08:44:55 +0000Collected Evidence: Collected Evidence: Directly plant peatland trees/shrubs Eleven studies evaluated the effects, on peatland vegetation, of planting trees/shrubs to restore or create forested/shrubby peatland. Seven studies were in tropical peat swamps, three in bogs and one in a fen. Survival (10 studies): Eight studies (seven replicated) in peat swamp forests in Thailand, Malaysia and Indonesia and bogs in Canada reported that the majority of planted trees/shrubs survived over periods between 10 weeks and 13 years. Species with <50% survival included Dacryodes, poplar and katok. One replicated study in a fen in the USA reported that most planted willow cuttings died within two years. One study in a peat swamp forest in Indonesia reported <5% survival of planted trees after five months, following unusually deep flooding. Growth (5 studies): Four studies (including two replicated, before-and-after) in peat swamp forests in Thailand, Indonesia and Malaysia reported that planted trees grew. One replicated before-and-after study in bogs in Canada reported that planted shrubs grew. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1820https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1820Tue, 28 Nov 2017 08:45:21 +0000Collected Evidence: Collected Evidence: Add mosses to peatland surface Thirteen studies evaluated the effects of adding mosses or moss fragments onto peatland surfaces. Eleven were in bogs and two in were in fens. One study was a continuation of an earlier study. Three of the studies involved sowing moss in gel beads. Sphagnum moss cover (12 studies): Eleven studies in bogs in the UK, Canada, Finland and Germany and fens the USA reported that Sphagnum moss was present, after 1–4 growing seasons, in at least some plots sown with Sphagnum. Cover ranged from negligible to >90%. Six of these studies were controlled and found that Sphagnum cover or abundance was higher in sown than unsown plots. One of the studies reported that Sphagnum only survived in one of three sites, and only when plots were mulched. One additional study in Canada found that adding Sphagnum to bog pools did not affect Sphagnum Other moss cover (4 studies): Four studies (including one replicated, randomized, paired, controlled, before-and-after) in bogs in Canada and fens in Sweden and the USA reported that mosses or bryophytes other than Sphagnum were present, after 2–3 growing seasons, in at least some plots sown with moss fragments. Cover ranged from negligible to 76%. In the fens in Sweden and the USA, moss cover was low (<1%) unless the plots were mulched, shaded or limed. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1821https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1821Tue, 28 Nov 2017 08:45:38 +0000Collected Evidence: Collected Evidence: Add mixed vegetation to peatland surface Eighteen studies evaluated the effects on peatland vegetation of spreading mixed vegetation onto the peatland surface. All 18 studies were in bogs (two being restored as fens). One study was a continuation of an earlier study. Characteristic plants (1 study): One replicated, randomized, paired, controlled, before-and-after study in a degraded bog in Canada found that adding fen vegetation increased the number and cover of fen-characteristic plant species. Sphagnum moss cover (17 studies): Seventeen replicated studies (five also randomized, paired, controlled, before-and-after) in bogs in Canada, the USA and Estonia reported that Sphagnum moss was present, after 1–6 growing seasons, in at least some plots sown with vegetation containing Sphagnum. Cover ranged from <1 to 73%. Six of the studies were controlled and found that Sphagnum cover was higher in sown than unsown plots. Five of the studies reported that Sphagnum cover was very low (<1%) unless plots were mulched after spreading fragments. Other moss cover (8 studies): Eight replicated studies (seven before-and-after, one controlled) in bogs in Canada, the USA and Estonia reported that mosses or bryophytes other than Sphagnum were present, after 1–6 growing seasons, in at least some plots sown with mixed peatland vegetation. Cover was <1–65%. Vascular plant cover (10 studies): Ten replicated studies in Canada, the USA and Estonia reported that vascular plants appeared following addition of mixed vegetation fragments to bogs. Two of the studies were controlled: one found that vascular plant cover was significantly higher in sown than unsown plots, but one found that sowing peatland vegetation did not affect herb cover. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1822https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1822Tue, 28 Nov 2017 08:45:54 +0000Collected Evidence: Collected Evidence: Introduce seeds of peatland herbs Ten studies evaluated the effects, on peatland vegetation, of introducing seeds of herbaceous peatland plants. Seven studies were in fens or fen meadows, two in bogs and one in unspecified peatland. Germination (2 studies): Two replicated studies reported that some planted herb seeds germinated. In a bog in Germany three of four species germinated, but in a fen in the USA only one of seven species germinated. Characteristic plants (3 studies): Three studies (two controlled) in fen meadows in Germany and a peatland in China reported that wetland-characteristic or peatland-characteristic plants colonized plots where herb seeds were sown (sometimes along with other interventions). Herb cover (4 studies): Three before-and-after studies (one also replicated, randomized, paired, controlled) in a bog in New Zealand, fen meadows in Switzerland and a peatland in China reported that plots sown with herb seeds developed cover of the sown herbs (and in New Zealand, greater cover than unsown plots). In China, the effect of sowing was not separated from the effects of other interventions. One replicated, randomized, paired, controlled study in a fen in the USA found that plots sown with herb (and shrub) seeds developed similar herb cover to plots that were not sown. Overall vegetation cover (3 studies): Of three replicated, controlled studies, one in a fen in the USA found that sowing herb (and shrub) seeds increased total vegetation cover. One study in a bog in New Zealand found that sowing herb seeds had no effect on total vegetation cover. One study in a fen meadow in Poland found that the effect of adding seed-rich hay depended on other treatments applied to plots. Overall plant richness/diversity (4 studies): Two replicated, controlled studies in fens in the USA and Poland found that sowing herb seeds had no effect on plant species richness (total or vascular). Two replicated, controlled, before-and-after studies in a bog in New Zealand and a fen meadow in Poland each reported inconsistent effects of herb sowing on total plant species richness. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1823https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1823Tue, 28 Nov 2017 08:46:08 +0000Collected Evidence: Collected Evidence: Introduce seeds of peatland trees/shrubs Five studies evaluated the effects, on peatland vegetation, of introducing seeds of peatland trees/shrubs to restore or create forested/shrubby peatland. Three studies were in bogs and two were in fens. Germination (2 studies): Two replicated studies in a bog in Germany and a fen in the USA reported germination of heather and willow seeds, respectively, in at least some sown plots. Survival (2 studies): One replicated study in a bog in Germany reported survival of some heather seedlings over two years. One replicated study in a fen in the USA reported that all germinated willow seedlings died within one month. Shrub cover (3 studies): Two studies (one replicated, randomized, paired, controlled) in bogs in New Zealand and Estonia reported that plots sown with shrub seeds (sometimes along with other interventions) developed greater cover of some shrubs than plots that were not sown: sown manuka or naturally colonizing heather (but not sown cranberry). One replicated, randomized, paired, controlled study in a fen in the USA found that plots sown with shrub (and herb) seeds developed similar overall shrub cover to unsown plots within two years. Overall vegetation cover (3 studies): Two replicated, randomized, paired, controlled studies in a bog in New Zealand and a fen in the USA reported that plots sown with shrub (and herb) seeds developed greater total vegetation cover than unsown plots after two years. One site comparison study in bogs in Estonia reported that sowing shrub seeds (along with fertilization) had no effect on total vegetation cover after 25 years. Overall plant richness/diversity (3 studies): One site comparison study in bogs in Estonia reported that sowing shrub seeds (along with fertilization) increased plant species richness. However, one replicated, randomized, paired, controlled study in a bog in New Zealand reported that plots sown with shrub seeds typically contained fewer plant species than plots that were not sown. One replicated, randomized, paired, controlled study in a fen in the USA found that sowing shrub (and herb) seeds had no effect on plant species richness. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1824https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1824Tue, 28 Nov 2017 08:46:23 +0000Collected Evidence: Collected Evidence: Add lime (before/after planting) Six studies evaluated the effects on peatland vegetation of liming areas planted with peatland plants. Four studies involved fen plants, one involved bog plants and one involved peat swamp plants. Two of the studies were in greenhouses/nurseries. Survival (2 studies): One replicated, controlled study in the Netherlands reported that liming typically reduced survival of planted fen herbs after two growing seasons. One replicated, randomized, paired, controlled study in Sweden found that liming increased survival of planted fen mosses over one growing season. Growth (3 studies): Two controlled, before-and-after studies found that liming did not increase growth of planted peatland vegetation. Liming reduced or had no effect on Sphagnum moss growth in bog pools in the UK, and reduced growth rates for the majority of peat swamp tree seedlings in a nursery in Indonesia. One replicated, controlled, before-and-after study in Sweden found that liming increased growth of planted fen mosses. Cover (2 studies): One replicated, randomized, paired, controlled, before-and-after study in a fen in Sweden found that liming increased cover of sown mosses. However, one replicated, randomized, paired, controlled study in a bog in Canada found that liming plots sown with fen vegetation fragments had no effect on total vegetation, vascular plant or bryophyte cover. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1825https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1825Tue, 28 Nov 2017 08:50:30 +0000Collected Evidence: Collected Evidence: Add inorganic fertilizer (before/after planting) Nine studies evaluated the effects, on peatland vegetation, of adding inorganic fertilizer to areas planted with peatland plants. Eight studies were in bogs (two being restored as fens). One study was in a tropical peat swamp nursery. Survival (2 studies): Two replicated, randomized, paired, controlled studies in bogs in Canada examined the effect, on plant survival, of adding inorganic fertilizer to areas planted with peatland plants. One study reported that fertilizer increased survival of two planted tree species. The other study found that fertilizer had no effect on three planted tree species and reduced survival of one. Growth (6 studies): Five studies (three replicated, randomized, paired, controlled) in bogs in the UK, Germany and Canada found that fertilizer typically increased growth of planted mosses, herbs or trees. However, for some species or in some conditions, fertilizer had no effect on growth. One replicated, randomized, controlled, before-and-after study in a nursery in Indonesia found that fertilizer typically had no effect on growth of peat swamp tree seedlings. Cover (3 studies): Three replicated, randomized, paired, controlled studies examined the effect, on vegetation cover, of fertilizing areas planted with peatland plants. One study in a bog in Canada found that fertilizer increased total vegetation, vascular plant and bryophyte cover. Another study in a bog (being restored as a fen) in Canada found that fertilizer increased sedge cover but had no effect on total vegetation cover, total herb cover or Sphagnum moss cover. One study in a bog in New Zealand reported that fertilizer typically increased cover of a sown shrub and rush, but this depended on the chemical in the fertilizer and preparation of the peat. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1826https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1826Tue, 28 Nov 2017 08:50:44 +0000Collected Evidence: Collected Evidence: Cover peatland with organic mulch (after planting) Twelve studies evaluated the effects, on peatland vegetation, of adding organic mulch after planting peatland plants. Nine studies were in bogs (one being restored as a fen). Two studies were in fens. One was in a tropical peat swamp. Germination (1 study): One replicated, controlled, before-and-after study in a bog in Germany found that mulching after sowing seeds increased germination rates for two species (a grass and a shrub), but had no effect on three other herb species. Survival (3 studies): Two replicated, paired, controlled studies in a fen in Sweden and a bog in the USA reported that mulching increased survival of planted vegetation (mosses or sedges). One replicated, paired, controlled study in Indonesia reported that mulching with oil palm fruits reduced survival of planted peat swamp tree seedlings. Growth (1 study): One replicated, randomized, paired, controlled, before-and-after study in a fen in the USA reported that mulching increased growth of transplanted sedges. Cover (9 studies): Six studies (including four replicated, randomized, paired, controlled, before-and-after) in bogs in Canada and the USA and a fen in Sweden found that mulching after planting increased vegetation cover (specifically total vegetation, total mosses/bryophytes, Sphagnum mosses or vascular plants after 1–3 growing seasons). Three replicated, randomized, paired, controlled, before-and-after studies in degraded bogs in Canada found that mulching after planting had no effect on vegetation cover (Sphagnum mosses or fen-characteristic plants). Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1828https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1828Tue, 28 Nov 2017 08:51:42 +0000Collected Evidence: Collected Evidence: Cover peatland with something other than mulch (after planting) Eight studies evaluated the effects, on peatland vegetation, of adding covers (other than mulch) after planting peatland plants. Five studies involved bog plants, two involved fen plants and one involved peat swamp plants. Two of the studies were in greenhouses or nurseries. Germination (1 study): One replicated, controlled, before-and-after study in a bog in Germany reported mixed effects of fleece and fibre mats on germination of sown herb and shrub seeds (positive or no effect, depending on species). Survival (2 studies): Two replicated, randomized, controlled studies examined the effect, on plant survival, of covering planted areas. One study in a fen in Sweden reported that shading with plastic mesh increased survival of planted mosses. One study in a nursery in Indonesia reported that shading with plastic mesh typically had no effect on survival of peat swamp tree species, but increased survival of some. Growth (3 studies): Three replicated, randomized, controlled, before-and-after studies examined the effect, on plant growth, of covering planted areas. One study in a greenhouse in Switzerland found that covering planted Sphagnum mosses with transparent plastic sheets or shading mesh increased their growth. One study in a fen in Sweden found that shading with plastic mesh reduced growth of planted fen mosses. One study in a nursery in Indonesia reported that seedlings shaded with plastic mesh grew taller and thinner than unshaded seedlings. Cover (4 studies): Two replicated, paired studies in a fen in Sweden and a bog in Australia reported that shading plots with plastic mesh increased cover of planted mosses. One study in a bog in Canada found that covering sown plots with plastic mesh, not transparent plastic sheets, increased the number of Sphagnum moss shoots. Another study in a bog in Canada reported that shading sown plots with plastic mesh had no effect on cover of vegetation overall, vascular plants, Sphagnum or other moss. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1829https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1829Tue, 28 Nov 2017 08:51:57 +0000Collected Evidence: Collected Evidence: Reprofile/relandscape peatland (before planting) Four studies evaluated the effects, on peatland vegetation, of reprofiling or relandscaping before planting peatland plants. All four studies were in bogs. Survival (1 study): One replicated, paired, controlled study in a bog in Canada found that survival of sown Sphagnum mosses was higher, after one growing season, in reprofiled basins than on raised plots. Cover (3 studies): Two replicated, controlled, before-and-after studies in bogs in Canada found that reprofiled basins had higher Sphagnum cover than raised plots, 3–4 growing seasons after sowing Sphagnum-dominated vegetation fragments. However, one controlled study in a bog in Estonia reported that total Sphagnum cover did not differ between reprofiled and raised plots, 1–2 years after sowing. All three studies found that reprofiled and raised plots developed similar cover of other mosses/bryophytes and vascular plants. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1833https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1833Tue, 28 Nov 2017 08:52:58 +0000Collected Evidence: Collected Evidence: Add root-associated fungi to plants (before planting) Three studies evaluated the effects of adding root-associated fungi to planted peatland vegetation. All three studies involved peat swamp tree seedlings: two in the wild and one in a nursery. Survival (2 studies): Two controlled studies (one also replicated, paired, before-and-after) in peat swamps in Indonesia found that adding root fungi did not affect survival of planted red balau or jelutong in all or most cases. However, one fungal treatment increased red balau survival in one study. Growth (3 studies): Two replicated, controlled, before-and-after studies (one also paired) of peat swamp trees in Indonesia found that adding root fungi to seedlings had no effect on growth: for red balau and jelutong or the majority of 15 tested species. However, one controlled study in Indonesia found that adding root fungi increased growth of red balau seedlings. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1841https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1841Tue, 28 Nov 2017 08:55:55 +0000