Collected Evidence: Collected Evidence: Add inorganic fertilizer: freshwater marshes One study evaluated the effects, on vegetation, of adding inorganic fertilizer to restore or create freshwater marshes. The study was in Germany. VEGETATION COMMUNITY Community composition (1 study): One replicated, paired, controlled, before-and-after study in wet grasslands in Germany reported that the effect of annual fertilization (for 20 years) on the average moisture preference of the vegetation varied between sites. Overall richness/diversity (1 study): The same study reported that the effect of annual fertilization (for 20 years) on total plant species richness varied between sites. VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, paired, controlled study in wet grasslands in Germany reported that plots fertilized every spring contained more vegetation biomass, after 4–18 years, than unfertilized plots. Herb abundance (1 study): The same study reported that the effect of annual fertilization (for 20 years) on cover of herb groups (sedges, rushes, forbs, ferns, grasses and legumes) varied between sites. VEGETATION STRUCTURE Height (1 study): One replicated, paired, controlled, before-and-after study in wet grasslands in Germany reported that the effect of annual fertilization (for 20 years) on vegetation height varied between sites. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3239https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3239Sat, 10 Apr 2021 12:11:20 +0100Collected Evidence: Collected Evidence: Add inorganic fertilizer: brackish/salt marshes One study evaluated the effects, on vegetation, of adding inorganic fertilizer to restore or create brackish/salt marshes. The study was in Canada. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Characteristic plant abundance (1 study): One replicated, paired, controlled, before-and-after study in salt-contaminated bogs in Canada found that adding fertilizer had no significant effect on cover of salt marsh vegetation, in unplanted plots, after one year. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3240https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3240Sat, 10 Apr 2021 12:12:30 +0100Collected Evidence: Collected Evidence: Add inorganic fertilizer: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of adding inorganic fertilizer 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%2F3242https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3242Sat, 10 Apr 2021 12:12:53 +0100Collected Evidence: Collected Evidence: Add below-ground organic matter: freshwater marshesWe found no studies that evaluated the effects, on vegetation, of adding below-ground organic matter to restore or create 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%2F3243https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3243Sat, 10 Apr 2021 12:32:54 +0100Collected Evidence: Collected Evidence: Add below-ground organic matter: brackish/salt marshes One study evaluated the effects, on vegetation, of adding below-ground organic matter to restore or create brackish/salt marshes. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Individual species abundance (1 study): One replicated, randomized, controlled, before-and-after study in a salt marsh in the USA found that plots amended with alginate contained a greater density of smooth cordgrass Spartina alterniflora than unamended plots after 6–52 weeks. However, amended and unamended plots contained similar smooth cordgrass biomass when it was sampled after 52 weeks. VEGETATION STRUCTURE Height (1 study): One replicated, randomized, controlled, before-and-after study in a salt marsh in the USA found that amending plots with alginate had no significant effect on smooth cordgrass height in the first 16 weeks after intervention, but that amended plots contained taller smooth cordgrass than unamended plots after 28–52 weeks. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3244https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3244Sat, 10 Apr 2021 12:33:05 +0100Collected Evidence: Collected Evidence: Add below-ground organic matter: freshwater swampsWe found no studies that evaluated the effects, on vegetation, of adding below-ground organic matter 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%2F3245https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3245Sat, 10 Apr 2021 12:33:22 +0100Collected Evidence: Collected Evidence: Add below-ground organic matter: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of adding below-ground organic matter 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%2F3246https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3246Sat, 10 Apr 2021 12:33:31 +0100Collected Evidence: Collected Evidence: Add cover other than mulchWe found no studies that evaluated the effects, on vegetation, of using cover other than mulch to restore/create 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%2F3251https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3251Sat, 10 Apr 2021 13:03:16 +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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