Collected Evidence: Collected Evidence: Reduce fertilizer or herbicide use: freshwater swampsWe found no studies that evaluated the effects, on vegetation in freshwater swamps, of reducing the amount of fertilizer or herbicide used in the swamps or adjacent areas.   ‘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%2F3154https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3154Mon, 05 Apr 2021 15:48:47 +0100Collected Evidence: Collected Evidence: Reduce fertilizer or herbicide use: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation in brackish/saline swamps, of reducing the amount of fertilizer or herbicide used in the swamps or adjacent areas.   ‘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%2F3155https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3155Mon, 05 Apr 2021 15:48:59 +0100Collected Evidence: Collected Evidence: Manage fertilizer or herbicide applicationWe found no studies that evaluated the effects, on vegetation in marshes or swamps, of managing fertilizer or herbicide use in these habitats or adjacent areas.   ‘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%2F3156https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3156Tue, 06 Apr 2021 12:13:49 +0100Collected Evidence: Collected Evidence: Add lime or similar chemicals: freshwater marshes One study evaluated the effects, on vegetation, of adding neutralizing chemicals to freshwater marshes or their catchments. The study was in the USA. VEGETATION COMMUNITY Relative abundance (1 study): One replicated, controlled, before-and-after study of marsh vegetation in the USA found that liming had little effect on the relative abundance of plant taxa. For 48 of 49 taxa, differences or similarities in relative abundance between limed and unlimed areas before intervention persisted over two years after intervention. VEGETATION ABUNDANCE Individual species abundance (1 study): One replicated, controlled, before-and-after study of marsh vegetation in the USA found that for most plant taxa, differences or similarities in abundance between limed and unlimed areas before intervention persisted over two years following intervention. This was true for 33 of 38 herbaceous plant taxa, eight of eight woody plant taxa, and two of three moss taxa. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3157https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3157Tue, 06 Apr 2021 12:16:26 +0100Collected Evidence: Collected Evidence: Add lime or similar chemicals: brackish/salt marshesWe found no studies that evaluated the effects, on vegetation, of adding neutralizing chemicals to brackish/salt marshes or their catchments.   ‘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%2F3158https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3158Tue, 06 Apr 2021 12:16:51 +0100Collected Evidence: Collected Evidence: Add lime or similar chemicals: freshwater swamps One study evaluated the effects, on vegetation, of adding neutralizing chemicals to freshwater swamps or their catchments. The study was in the USA. VEGETATION COMMUNITY Relative abundance (1 study): One replicated, controlled, before-and-after study of shrubby wetland vegetation in the USA found that liming had no significant effect on the relative abundance of plant taxa. For 49 of 49 taxa, differences or similarities in relative abundance between limed and unlimed areas before intervention persisted over two years after intervention. VEGETATION ABUNDANCE Individual species abundance (1 study): One replicated, controlled, before-and-after study of shrubby wetland vegetation in the USA found that for most plant taxa, differences or similarities in abundance between limed and unlimed areas before intervention persisted over two years following intervention. This was true for 31 of 31 herbaceous plant taxa, 16 of 16 woody plant taxa, and one of two moss taxa. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3159https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3159Tue, 06 Apr 2021 12:17:03 +0100Collected Evidence: Collected Evidence: Add lime or similar chemicals: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of adding neutralizing chemicals to brackish/saline swamps or their catchments.   ‘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%2F3160https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3160Tue, 06 Apr 2021 12:17:14 +0100Collected Evidence: Collected Evidence: Remove debris from freshwater marshesWe found no studies that evaluated the effects, on vegetation, of removing debris from freshwater 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%2F3161https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3161Tue, 06 Apr 2021 12:48:54 +0100Collected Evidence: Collected Evidence: Remove debris from brackish/salt marshes Two studies evaluated the effects, on vegetation, of removing debris from brackish/salt marshes. Both studies were in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, paired, site comparison study in a salt marsh in the USA found that overall vegetation cover in patches where debris had been removed remained lower than in undisturbed marsh for one growing season, but had recovered to match undisturbed marsh after two growing seasons. Individual species abundance (2 studies): Two studies quantified the effect of this action on the abundance of individual plant species. For example, the two replicated, site comparison studies in salt marshes in the USA found that the abundance of dominant herb species in impacted vegetation patches was typically lower than in undisturbed marsh one growing season after removing debris, but was sometimes similar to undisturbed marsh. The results depended on the species, metric and type of debris removed. One of the studies also monitored until the second growing season after removing debris; at this point, the cover of both dominant herb species had recovered to match undisturbed marsh. VEGETATION STRUCTURE Height (1 study): One replicated, before-and-after, site comparison study in a salt marsh in the USA found that the maximum height of smooth cordgrass recovered, to match undisturbed marsh, within 45 weeks of removing debris. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3162https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3162Tue, 06 Apr 2021 12:49:05 +0100Collected Evidence: Collected Evidence: Remove debris from freshwater swampsWe found no studies that evaluated the effects, on vegetation, of removing debris from 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%2F3163https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3163Tue, 06 Apr 2021 12:49:15 +0100Collected Evidence: Collected Evidence: Remove debris from brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of removing debris from 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%2F3164https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3164Tue, 06 Apr 2021 12:49:30 +0100Collected Evidence: Collected Evidence: Put up signs to discourage litteringWe found no studies that evaluated the effects, on vegetation or human behaviour, of putting up signs to discourage littering in/near 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%2F3165https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3165Tue, 06 Apr 2021 13:16:24 +0100Collected Evidence: Collected Evidence: Modify crop farming practices in watershed to reduce pollution: freshwater marshes One study evaluated the effects, on vegetation in freshwater marshes, of modifying crop farming practices in the watershed to reduce pollution. The study was in the USA. VEGETATION COMMUNITY Community composition (1 study): One replicated, site comparison study in the USA reported that freshwater marshes being restored by abandoning cropland in the watershed (along with removing topsoil from the marshes) contained a different overall plant community, after 1–12 years, to both natural and degraded marshes nearby. Overall richness/diversity (1 study): The same study reported that freshwater marshes being restored by abandoning cropland in the watershed (along with removing topsoil from the marshes) contained fewer wetland plant species, after 1–12 years, than nearby natural marshes. VEGETATION ABUNDANCE   VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3166https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3166Tue, 06 Apr 2021 13:17:51 +0100Collected Evidence: Collected Evidence: Modify crop farming practices in watershed to reduce pollution: brackish/salt marshesWe found no studies that evaluated the effects, on vegetation in brackish/salt marshes, of modifying crop farming practices in the watershed to reduce 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%2F3167https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3167Tue, 06 Apr 2021 13:18:03 +0100Collected Evidence: Collected Evidence: Modify crop farming practices in watershed to reduce pollution: freshwater swampsWe found no studies that evaluated the effects, on vegetation in freshwater swamps, of modifying crop farming practices in the watershed to reduce 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%2F3168https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3168Tue, 06 Apr 2021 13:18:13 +0100Collected Evidence: Collected Evidence: Modify crop farming practices in watershed to reduce pollution: brackish/saline swampsWe found no studies that evaluated the effects, vegetation in brackish/saline swamps, of modifying crop farming practices in the watershed to reduce 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%2F3169https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3169Tue, 06 Apr 2021 13:18:27 +0100Collected Evidence: Collected Evidence: Modify logging practices in watershed to reduce pollutionWe found no studies that evaluated the effects, on vegetation in marshes or swamps, of modifying logging practices in the watershed to reduce 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%2F3170https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3170Tue, 06 Apr 2021 13:35:53 +0100Collected Evidence: Collected Evidence: Modify livestock farming practices in watershed to reduce pollutionWe found no studies that evaluated the effects, on vegetation in marshes or swamps, of modifying livestock farming practices in the watershed to reduce 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%2F3171https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3171Tue, 06 Apr 2021 13:38:04 +0100Collected Evidence: Collected Evidence: Modify aquaculture practices in watershed to reduce pollutionWe found no studies that evaluated the effects, on vegetation in marshes or swamps, of modifying aquacultural practices in the watershed to reduce 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%2F3172https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3172Tue, 06 Apr 2021 13:39:18 +0100Collected Evidence: Collected Evidence: Physically or chemically remove oilWe found no studies that evaluated the effects, on vegetation, of physically or chemically removing oil (but not vegetation) from 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%2F3173https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3173Tue, 06 Apr 2021 13:40:33 +0100Collected Evidence: Collected Evidence: Cut or burn oil-contaminated vegetation: freshwater marshesWe found no studies that evaluated the effects, on vegetation, of cutting or burning oil-contaminated vegetation in freshwater 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%2F3174https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3174Tue, 06 Apr 2021 13:40:59 +0100Collected Evidence: Collected Evidence: Cut or burn oil-contaminated vegetation: brackish/salt marshes Two studies evaluated the effects, on vegetation, of cutting or burning oil-contaminated vegetation in brackish/salt marshes. One study reviewed multiple cases from the UK and the USA. The other study was in Brazil. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (1 study): One review of studies in oil-contaminated salt marshes in the UK and the USA reported that in eight of eight cases with quantitative comparisons between cut and uncut areas, cutting had no clear benefit for vegetation abundance (density, biomass or cover) over 8–29 months of recovery. Individual species abundance (1 study): One replicated, paired, controlled, site comparison study in oil-contaminated brackish/salt marshes in Brazil found that smooth cordgrass Spartina alterniflora density and biomass were never greater in cut than uncut plots (and typically similar under each treatment), over nine months after cutting. VEGETATION STRUCTURE Height (1 study): One replicated, paired, controlled, site comparison study in oil-contaminated brackish/saline marshes in Brazil found that smooth cordgrass Spartina alterniflora was never taller in cut than uncut plots (typically similar height under each treatment) over nine months after cutting. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3175https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3175Tue, 06 Apr 2021 13:41:15 +0100Collected Evidence: Collected Evidence: Cut or burn oil-contaminated vegetation: freshwater swampsWe found no studies that evaluated the effects, on vegetation, of cutting or burning oil-contaminated vegetation in 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%2F3176https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3176Tue, 06 Apr 2021 13:41:35 +0100Collected Evidence: Collected Evidence: Cut or burn oil-contaminated vegetation: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of cutting or burning oil-contaminated vegetation in 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%2F3177https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3177Tue, 06 Apr 2021 13:41:47 +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 +0100
What Works 2021 cover

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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