Collected Evidence: Collected Evidence: Use barriers to keep livestock off ungrazed brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of using barriers to keep livestock off brackish/saline swamps that have never (or not recently) been grazed.   ‘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%2F2965https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2965Thu, 25 Mar 2021 14:14:42 +0000Collected Evidence: Collected Evidence: Thin vegetation to prevent wild firesWe found no studies that evaluated the effects, on marsh/swamp vegetation, of thinning vegetation to prevent wild fires in or near these habitats.   ‘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%2F3078https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3078Fri, 02 Apr 2021 16:54:10 +0100Collected Evidence: Collected Evidence: Use artificial barriers to block pollutionWe found no studies that evaluated the effects, on marsh or swamp vegetation, of using artificial barriers to block out pollution.   ‘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%2F3149https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3149Mon, 05 Apr 2021 15:42:15 +0100Collected Evidence: Collected Evidence: Stimulate microbial breakdown of oilWe found no studies that evaluated the effects, on vegetation, of stimulating microbial breakdown of oil in contaminated marshes or swamps.   ‘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%2F3178https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3178Tue, 06 Apr 2021 16:11:08 +0100Collected Evidence: Collected Evidence: Transplant or replace blocks of vegetation: freshwater marshes Four studies evaluated the effects, on vegetation, of transplanting or replacing blocks of freshwater marsh vegetation. Three studies were in the USA. One study was in the UK. VEGETATION COMMUNITY Community composition (1 study): One replicated, paired, controlled study in rewetted marshes in the USA found that plots of transplanted marsh vegetation contained a plant community characteristic of wetter conditions than plots without transplants after one growing season – but not after two. Overall richness/diversity (2 studies): One replicated, before-and-after study in the UK reported that plant species richness within transplanted freshwater marsh vegetation was similar before transplanting and six years later. There was a temporary increase in richness after one year. One replicated, paired, controlled study in rewetted freshwater marshes in the USA found that plots of transplanted marsh vegetation contained more wetland plant species than plots without transplants after one growing season – but that there was no significant difference after two. VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, paired, controlled study in rewetted freshwater marshes in the USA found that plots of transplanted marsh vegetation had greater cover of wetland plants than plots without transplants, after 1–2 growing seasons. Individual species abundance (2 studies): One replicated, site comparison study in a wet prairie in the USA found that after three growing seasons, the density of prairie cordgrass Spartina pectinata stems was lower in transplanted sods than in pristine or source prairies. One before-and-after study of transplanted freshwater marsh vegetation in the UK reported changes in the frequency of individual plant species from before to six years after transplanting. VEGETATION STRUCTURE Height (1 study): One replicated, site comparison study in a wet prairie in the USA found that after three growing seasons, prairie cordgrass Spartina pectinata was shorter in transplanted sods than in pristine or source prairies. Diameter/perimeter/area (2 studies): Two studies (one replicated) in wet prairies in the USA found that the average area of small transplanted sods (≤0.28 m2 initial size) increased over 3–4 growing seasons. One of the studies transplanted larger sods (0.65 m2 initial size) and reported that their average area decreased over 3–4 growing seasons. OTHER Survival (2 studies): Two studies (one replicated) in wet prairies in the USA reported ≥90% survival of transplanted sods of wet prairie vegetation after 3–4 growing seasons. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3268https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3268Sat, 10 Apr 2021 15:36:31 +0100Collected Evidence: Collected Evidence: Transplant or replace blocks of vegetation: brackish/salt marshes One study evaluated the effects, on vegetation, of transplanting or replacing blocks of brackish/salt marsh vegetation. The study was in Australia. VEGETATION COMMUNITY Community composition (1 study): One replicated, controlled, site comparison study in an estuarine salt marsh in Australia found that areas where sods of saltwater couch Sporobolus virginicus were transplanted had a similar overall plant community composition to areas without transplants, after 3–4 years. The plant community in the transplanted areas was >70% similar to natural areas in only 4 of 12 comparisons. VEGETATION ABUNDANCE   VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3269https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3269Sat, 10 Apr 2021 15:36:47 +0100Collected Evidence: Collected Evidence: Transplant or replace wetland soil: freshwater marshes Ten studies evaluated the effects, on vegetation, of transplanting wetland soil to restore or create freshwater marshes. Nine studies were in the USA. One study was in Guam. Two studies were in the same region but used different sites. VEGETATION COMMUNITY Community composition (3 studies): Two replicated, controlled studies in rewetted marshes in the USA found that areas amended with wetland soil contained a plant community characteristic of wetter conditions than unamended plots after one growing season – but not after two. One replicated, randomized, controlled study in a recently excavated marsh in the USA found that amended and unamended plots contained a plant community of similar overall wetness after both one and two growing seasons. Overall richness/diversity (10 studies): Eight studies (including four at least replicated and controlled) in freshwater marshes in the USA reported that areas amended with wetland soil had greater plant richness and/or diversity than unamended areas and/or nearby natural marshes. One replicated, paired, controlled study in rewetted freshwater marshes in the USA found that plots amended with sieved marsh soil contained a similar number of wetland plant species to unamended plots, after 1–2 growing seasons. One before-and-after study of freshwater pool in Guam simply quantified plant species richness one year after adding wetland soil (along with other interventions). Characteristic plant richness/diversity (1 study): One replicated, randomized, paired, controlled study in a freshwater marsh in the USA reported that plots amended with wetland soil developed a greater richness of wetland-characteristic plant species than unamended plots, at the end of the growing season. VEGETATION ABUNDANCE Overall abundance (6 studies): Six controlled studies in freshwater marshes in the USA reported that plots amended with wetland soil typically contained more vegetation overall than unamended plots, after 1–2 growing seasons. This was true for cover and biomass, but not stem density. Individual species abundance (7 studies): Seven studies (including one replicated, randomized, paired, controlled, site comparison) in freshwater marshes, meadows and pools in the USA and Guam quantified the effect of this action (sometimes along with others) on the abundance of individual plant species. Results were mixed and likely depended on the composition of the donor wetland. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3270https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3270Sat, 10 Apr 2021 15:48:02 +0100Collected Evidence: Collected Evidence: Transplant or replace wetland soil: brackish/salt marshesWe found no studies that evaluated the effects on vegetation, of transplanting wetland soil to restore or create brackish/salt marshes.   ‘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%2F3271https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3271Sat, 10 Apr 2021 15:48:19 +0100Collected Evidence: Collected Evidence: Transplant or replace wetland soil: freshwater swampsWe found no studies that evaluated the effects on vegetation, of transplanting wetland soil to restore or create freshwater swamps.   ‘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%2F3272https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3272Sat, 10 Apr 2021 15:48:30 +0100Collected Evidence: Collected Evidence: Transplant or replace wetland soil: brackish/saline swampsWe found no studies that evaluated the effects on vegetation, of transplanting wetland soil to restore or create brackish/saline swamps.   ‘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%2F3273https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3273Sat, 10 Apr 2021 15:48:42 +0100Collected Evidence: Collected Evidence: Transplant wetland soil before/after planting non-woody plants: freshwater wetlands Two studies evaluated the effects, on vegetation, of transplanting wetland soil to freshwater wetlands planted with emergent, non-woody plants. One study was in the USA and one was in Canada. VEGETATION COMMUNITY Community composition (1 study): One replicated, site comparison study of created freshwater marshes in the USA found that those amended with marsh soil developed plant communities characteristic of wetter conditions than unamended marshes. Most marshes had also been planted. All were ≥5 years old. Overall richness/diversity (1 study): The same study found that marshes amended with marsh soil had similar (dry season) or lower (wet season) plant species richness and diversity to unamended marshes. Most marshes had also been planted. All were ≥5 years old. VEGETATION ABUNDANCE                 Overall abundance (1 study): One replicated, site comparison study of created freshwater marshes in the USA reported that amongst planted marshes, adding marsh soil had no significant effect on overall vegetation cover or biomass, after ≥5 years. Characteristic plant abundance (1 study): One replicated, site comparison study of created freshwater marshes in the USA reported that amongst planted marshes, those also amended with marsh soil had greater cover of wetland-characteristic plants than unamended marshes, after ≥5 years. Individual species abundance (1 study): One replicated, randomized, paired, controlled study in freshwater trenches in Canada found that adding peat-rich soil to pots of mine tailings before planting water sedge Carex aquatilis typically increased its above-ground biomass two growing seasons later. VEGETATION STRUCTURE   OTHER Survival (1 study): One replicated, randomized, paired, controlled study in freshwater trenches in Canada found that adding peat-rich soil to pots of mine tailings either increased or had no significant effect on survival of planted water sedge Carex aquatilis over two growing seasons. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3320https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3320Sun, 11 Apr 2021 12:33:22 +0100Collected Evidence: Collected Evidence: Transplant wetland soil before/after planting non-woody plants: brackish/saline wetlandsWe found no studies that evaluated the effects, on vegetation, of transplanting wetland soil to brackish/saline wetlands planted with emergent, non-woody plants.   ‘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%2F3321https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3321Sun, 11 Apr 2021 12:33:42 +0100Collected Evidence: Collected Evidence: Transplant wetland soil before/after planting trees/shrubs: freshwater wetlandsWe found no studies that evaluated the effects, on vegetation, of transplanting wetland soil to freshwater wetlands planted with trees/shrubs.   ‘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%2F3322https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3322Sun, 11 Apr 2021 12:33:50 +0100Collected Evidence: Collected Evidence: Transplant wetland soil before/after planting trees/shrubs: brackish/saline wetlandsWe found no studies that evaluated the effects, on vegetation, of transplanting wetland soil to brackish/saline wetlands planted with trees/shrubs.   ‘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%2F3323https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3323Sun, 11 Apr 2021 12:34:00 +0100Collected Evidence: Collected Evidence: Soak non-woody plants before planting: freshwater wetlandsWe found no studies that evaluated the effects – on emergent, non-woody plants typical of freshwater wetlands – of soaking them before planting.   ‘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%2F3359https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3359Sun, 11 Apr 2021 17:33:05 +0100Collected Evidence: Collected Evidence: Soak trees/shrubs before planting: freshwater wetlands One study evaluated the effects – on trees/shrubs typical of freshwater wetlands – of soaking them before planting. The study was in a greenhouse in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Biomass/plant (1 study): One replicated, randomized, controlled study in a greenhouse in the USA found that soaking black willow Salix nigra cuttings before planting had no significant effect on the above-ground biomass of surviving seedlings, over the 48 days after planting. OTHER Survival (1 study): One replicated, randomized, controlled study in a greenhouse in the USA found that the effect, on survival, of soaking black willow cuttings before planting depended on the water regime after planting. However, all cuttings soaked for 15 days before planting died within 42 days of planting. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3361https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3361Sun, 11 Apr 2021 17:33:34 +0100Collected Evidence: Collected Evidence: Soak trees/shrubs before planting: brackish/saline wetlandsWe found no studies that evaluated the effects – on trees/shrubs typical of brackish/saline wetlands – of soaking them before planting.   ‘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%2F3362https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3362Sun, 11 Apr 2021 17:33:44 +0100Collected Evidence: Collected Evidence: Soak seeds of non-woody plants before sowing: freshwater wetlands One study evaluated the effects – on emergent, non-woody plants typical of freshwater wetlands – of soaking their seeds before sowing. The study was in a greenhouse in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated, randomized, controlled study in a greenhouse in the USA found that soaking bulrush seeds in water before sowing typically had no significant effect on their germination rate – especially amongst seeds that had not been manipulated in any other way before soaking. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3363https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3363Sun, 11 Apr 2021 20:16:17 +0100Collected Evidence: Collected Evidence: Soak seeds of non-woody plants before sowing: brackish/saline wetlandsWe found no studies that evaluated the effects – on emergent, non-woody plants typical of brackish/saline wetlands – of soaking their seeds before sowing.   ‘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%2F3364https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3364Sun, 11 Apr 2021 20:16:50 +0100Collected Evidence: Collected Evidence: Soak tree/shrub seeds before sowing: freshwater wetlandsWe found no studies that evaluated the effects – on trees/shrubs typical of freshwater wetlands – of soaking their seeds before sowing.   ‘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%2F3365https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3365Sun, 11 Apr 2021 20:17:00 +0100Collected Evidence: Collected Evidence: Soak tree/shrub seeds before sowing: brackish/saline wetlandsWe found no studies that evaluated the effects – on trees/shrubs typical of brackish/saline wetlands – of soaking their seeds before sowing.   ‘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%2F3366https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3366Sun, 11 Apr 2021 20:17:12 +0100Collected Evidence: Collected Evidence: Treat seeds of non-woody plants with chemicals before sowing: freshwater wetlands Six studies evaluated the effects – on emergent, non-woody plants typical of freshwater wetlands – of treating their seeds with chemicals before sowing. All six studies were in greenhouses or laboratories in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Germination/emergence (6 studies): Of six replicated, controlled studies in greenhouses or laboratories in the USA, five identified chemicals that sometimes increased, and did not significantly reduce, the germination rate of herb seeds: potassium nitrate, nitric acid and bleach. The effect of these chemicals depended on factors such as the age of the seeds, the species and other pre-sowing treatments. Two of the studies identified chemicals that never had a significant effect on the germination rate of herb seeds: a plant hormone and sulfuric acid. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3380https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3380Mon, 12 Apr 2021 08:30:30 +0100Collected Evidence: Collected Evidence: Treat seeds of non-woody plants with chemicals before sowing: brackish/saline wetlandsWe found no studies that evaluated the effects – on emergent, non-woody plants typical of brackish/saline wetlands – of treating their seeds with chemicals before sowing.   ‘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%2F3381https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3381Mon, 12 Apr 2021 08:30:40 +0100Collected Evidence: Collected Evidence: Treat tree/shrub seeds with chemicals before sowing: freshwater wetlands Two studies evaluated the effects – on trees/shrubs typical of freshwater wetlands – of treating their seeds with chemicals before sowing. Both studies were in one laboratory in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE          OTHER Germination/emergence (2 studies): Two replicated, controlled studies in a laboratory in the USA found that soaking baldcypress Taxodium distichum seeds in weak sodium hydroxide increased their germination rate. One of the studies found that soaking in ethyl alcohol and/or hydrochloric acid reduced the germination rate. One of the studies found that soaking in stronger sodium hydroxide, or hydrogen peroxide and ethyl alcohol, had no significant effect on the germination rate. Growth (1 study): One replicated, controlled study in a laboratory in the USA found that soaking baldcypress Taxodium distichum seeds in chemicals before sowing typically had no significant effect on the height of surviving seedlings, 30 days after germination. Soaking in ethyl alcohol, however, reduced seedling height. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3382https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3382Mon, 12 Apr 2021 08:30:47 +0100Collected Evidence: Collected Evidence: Treat tree/shrub seeds with chemicals before sowing: brackish/saline wetlandsWe found no studies that evaluated the effects – on trees/shrubs typical of brackish/saline wetlands – of treating their seeds with chemicals before sowing.   ‘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%2F3383https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3383Mon, 12 Apr 2021 08:31:05 +0100
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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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