Collected Evidence: Collected Evidence: Raise water level (before/after planting)We found no studies that evaluated the effects, on vegetation, of raising the water level in areas planted with emergent marsh/swamp 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%2Fconservationevidencejournal.com%2Factions%2F3274https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3274Sat, 10 Apr 2021 17:03:59 +0100Collected Evidence: Collected Evidence: Lower water level (before/after planting)We found no studies that evaluated the effects, on vegetation, of lowering the water level in areas planted with emergent marsh/swamp 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%2Fconservationevidencejournal.com%2Factions%2F3275https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3275Sat, 10 Apr 2021 17:04:37 +0100Collected Evidence: Collected Evidence: Facilitate tidal exchange before/after planting non-woody plants: freshwater wetlandsWe found no studies that evaluated the effects, on vegetation, of facilitating tidal exchange in freshwater 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%2Fconservationevidencejournal.com%2Factions%2F3276https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3276Sat, 10 Apr 2021 17:07:18 +0100Collected Evidence: Collected Evidence: Facilitate tidal exchange before/after planting non-woody plants: brackish/saline wetlands Two studies evaluated the effects, on vegetation, of facilitating tidal exchange in brackish/saline wetlands planted with emergent, non-woody plants. Both studies were in the same estuarine site in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (1 study): One replicated, controlled study in a salt marsh in the USA found that planted California cordgrass Spartina foliosa reached a similar height, after three growing seasons, in areas with an excavated tidal creek and areas without a tidal creek. Individual plant size (1 study): One replicated, controlled study in a salt marsh in the USA found that planted salt marsh herbs reached a similar overall size, after 1–2 growing seasons, in areas with an excavated tidal creek and areas without a tidal creek. OTHER Survival (2 studies): Two replicated, controlled studies in a salt marsh in the USA found that planted salt marsh herbs typically had similar survival rates, after 1–2 growing seasons, in areas with an excavated tidal creek and areas without a tidal creek. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3277https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3277Sat, 10 Apr 2021 17:07:28 +0100Collected Evidence: Collected Evidence: Facilitate tidal exchange before/after planting trees/shrubs: freshwater wetlandsWe found no studies that evaluated the effects, on vegetation, of facilitating tidal exchange in 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%2Fconservationevidencejournal.com%2Factions%2F3278https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3278Sat, 10 Apr 2021 17:07:37 +0100Collected Evidence: Collected Evidence: Facilitate tidal exchange before/after planting trees/shrubs: brackish/saline wetlandsWe found no studies that evaluated the effects, on vegetation, of facilitating tidal exchange in 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%2Fconservationevidencejournal.com%2Factions%2F3279https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3279Sat, 10 Apr 2021 17:07:46 +0100Collected Evidence: Collected Evidence: Irrigate (before/after planting)We found no studies that evaluated the effects, on vegetation, of irrigating areas planted with emergent marsh/swamp 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%2Fconservationevidencejournal.com%2Factions%2F3280https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3280Sat, 10 Apr 2021 17:15:17 +0100Collected Evidence: Collected Evidence: Actively manage water level before/after planting non-woody plants: freshwater wetlands Three studies evaluated the effects, on vegetation, of actively managing water levels in freshwater wetlands planted with emergent, non-woody plants. All three studies were in the USA. Two studies used the same experimental wet basins but planted different species. VEGETATION COMMUNITY Overall richness/diversity (1 study): One study in a freshwater marsh in the USA found that amongst plots amended with wetland soil, those flooded for longer contained fewer emergent plant species over the rest of the growing season following drawdown. Characteristic plant richness/diversity (1 study): The same study found that amongst plots amended with wetland soil, those flooded for longer contained fewer wetland-characteristic plant species over the rest of the growing season following drawdown. VEGETATION ABUNDANCE  Overall abundance (1 study): One study in a freshwater marsh in the USA found that amongst plots amended with wetland soil, those flooded for longer developed more submerged vegetation biomass before drawdown, but developed less emergent vegetation (biomass and stem density) over the rest of the growing season after drawdown. Individual species abundance (2 studies): Two studies quantified the effect of this action on the abundance of individual plant species. For example, one controlled, before-and-after study in wet basins in the USA found that the effect of mimicking a natural (falling) water regime on lake sedge Carex lacustris biomass and density, in the three years after planting, depended on the year and various environmental factors (e.g. planting density, elevation and weeding of competitors). VEGETATION STRUCTURE Height (2 studies): Two controlled studies in wet basins in the USA examined the effect of mimicking a natural (falling) water regime, compared to a stable or rising regime, on the height of sedges over three years after planting. One of the studies found no significant effect on the height of tussock sedge Carex stricta in three of three years. The other study found that the effect on the height of lake sedge Carex lacustris varied within and between years. OTHER Survival (2 studies): Two controlled studies in wet basins in the USA examined the effect of mimicking a natural (falling) water regime, compared to a stable or rising regime, on the survival of sedges Carex over three years after planting. The precise effect depended on the year and/or plot elevation. In the first year, sedge survival was typically lower under the falling regime. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3281https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3281Sat, 10 Apr 2021 17:15:30 +0100Collected Evidence: Collected Evidence: Actively manage water level before/after planting non-woody plants: brackish/saline wetlandsWe found no studies that evaluated the effects, on vegetation, of actively managing water levels in 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%2Fconservationevidencejournal.com%2Factions%2F3282https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3282Sat, 10 Apr 2021 17:15:48 +0100Collected Evidence: Collected Evidence: Actively manage water level before/after planting trees/shrubs: freshwater wetlandsWe found no studies that evaluated the effects, on vegetation, of actively managing water levels in 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%2Fconservationevidencejournal.com%2Factions%2F3283https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3283Sat, 10 Apr 2021 17:15:55 +0100Collected Evidence: Collected Evidence: Reprofile/relandscape (before planting)We found no studies that evaluated the effects, on vegetation, of reprofiling/relandscaping before planting emergent marsh/swamp 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%2Fconservationevidencejournal.com%2Factions%2F3285https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3285Sat, 10 Apr 2021 17:30:50 +0100Collected Evidence: Collected Evidence: Create mounds or hollows before planting non-woody plants: freshwater wetlands Two studies evaluated the effects, on vegetation, of creating mounds or hollows in freshwater wetlands before planting emergent, non-woody plants. Both studies were in the same wetland in the USA, but used different experimental set-ups. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Individual species abundance (2 studies): Two replicated, randomized, paired, controlled studies in a wetland in the USA found that tussock sedge Carex stricta cover was typically similar across plots, after two growing seasons, whether sedges were planted into created mounds or hollows, or planted into flat ground. VEGETATION STRUCTURE Individual plant size (2 studies): Two replicated, randomized, paired, controlled studies in a wetland in the USA found that planting tussock sedges Carex stricta into created mounds or hollows had no significant effect on their individual biomass, after 1–2 growing seasons, when compared to planting into flat ground. OTHER Survival (2 studies): Two replicated, randomized, paired, controlled studies in a wetland in the USA found that planting tussock sedge Carex stricta into created mounds or hollows did not improve, and typically reduced, its survival rate compared to planting into flat ground. Survival was monitored after 1–2 growing seasons. Growth (2 studies): The same studies found that planting tussock sedge Carex stricta into created mounds or hollows typically had no significant effect on its growth rate, over 1–2 growing seasons, compared to planting into flat ground. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3286https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3286Sat, 10 Apr 2021 17:34:46 +0100Collected Evidence: Collected Evidence: Create mounds or hollows before planting non-woody plants: brackish/saline wetlands One study evaluated the effects, on vegetation, of creating mounds or hollows in brackish/saline wetlands before planting emergent, non-woody plants. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Individual species abundance (1 study): One replicated, randomized, paired, controlled study in an estuarine salt marsh in the USA found that amongst plots sown/planted with dwarf saltwort Salicornia bigelovii, those that had been excavated into depressions had lower cover of dominant pickleweed Salicornia virginica – over the first growing season – than plots left at ground level. VEGETATION STRUCTURE   OTHER Germination/emergence (1 study): One replicated, randomized, paired, controlled study in an estuarine salt marsh in the USA found that there were no more (sometimes fewer) dwarf saltwort Salicornia bigelovii seedlings in excavated depressions than in level plots, two months after sowing saltwort seeds. Survival (1 study): The same study found that the survival rate of dwarf saltwort Salicornia bigelovii transplants was not greater (sometimes lower) in excavated depressions than in level plots. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3287https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3287Sat, 10 Apr 2021 17:34:58 +0100Collected Evidence: Collected Evidence: Create mounds or hollows before planting trees/shrubs: freshwater wetlands Three studies evaluated the effects, on vegetation, of creating mounds or hollows in freshwater wetlands before planting trees/shrubs. All three studies were in the USA. VEGETATION COMMUNITY Community composition (1 study): One replicated, site comparison study of 10-year-old restored/created freshwater wetlands in the USA reported that adding coarse woody debris to wetlands before planting trees/shrubs affected the composition of the ground vegetation layer, but not the tree layer. Overall richness/diversity (2 studies): Two studies in freshwater wetlands in the USA reported that creating mounds or hollows before planting trees/shrubs had no clear or significant effect on plant species richness and diversity 10–12 years later. In one of the studies, the same was true for bryophyte, herb and woody plants richness separately. VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (1 study): One replicated, paired, controlled study in created freshwater wetlands in the USA found that the average height of white cedar Thuja occidentalis saplings typically increased more, between two and five years after planting, in created mounds than on lower (occasionally flooded) ground. OTHER                                         Survival (1 study): One replicated, paired, controlled study in created freshwater wetlands in the USA found that white cedar Thuja occidentalis seedlings had higher survival rates when planted into created mounds than on lower (occasionally flooded) ground. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3288https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3288Sat, 10 Apr 2021 17:35:08 +0100Collected Evidence: Collected Evidence: Create mounds or hollows before planting trees/shrubs: brackish/saline wetlands One study evaluated the effects, on vegetation, of creating mounds or hollows in brackish/saline wetlands before planting trees/shrubs. The study was in Brazil. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Survival (1 study): One replicated, controlled study in a degraded coastal swamp in Brazil reported that planting tree seedlings into mounds had mixed effects on survival over three years, depending on the species. Growth (1 study): The same study reported that tree seedlings planted into mounds typically grew at a similar rate, over three years, to seedlings planted at ground level. Growth was measured in terms of diameter, height and canopy area. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3289https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3289Sat, 10 Apr 2021 17:35:23 +0100Collected Evidence: Collected Evidence: Remove surface soil/sediment (before planting)We found no studies that evaluated the effects, on vegetation, of removing surface soil/sediment before planting emergent marsh/swamp 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%2Fconservationevidencejournal.com%2Factions%2F3290https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3290Sat, 10 Apr 2021 20:04:01 +0100Collected Evidence: Collected Evidence: Bury surface soil/sediment (before planting)We found no studies that evaluated the effects, on vegetation, of burying surface soil/sediment before planting emergent marsh/swamp 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%2Fconservationevidencejournal.com%2Factions%2F3291https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3291Sat, 10 Apr 2021 20:05:00 +0100Collected Evidence: Collected Evidence: Disturb soil/sediment surface before planting non-woody plants: freshwater wetlandsWe found no studies that evaluated the effects, on vegetation, of disturbing the surface of freshwater wetlands before planting 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%2Fconservationevidencejournal.com%2Factions%2F3292https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3292Sun, 11 Apr 2021 07:56:39 +0100Collected Evidence: Collected Evidence: Disturb soil/sediment surface before planting non-woody plants: brackish/saline wetlands Two studies evaluated the effects, on vegetation, of disturbing the surface of brackish/saline wetlands before planting emergent, non-woody plants. Both studies were in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Individual plant abundance (1 study): One study quantified the effect of this action on the abundance of individual plant species. The replicated, randomized, paired, controlled study in a salt marsh in the USA found that tilling sediment before planting California cordgrass Spartina foliosa had no significant effect on its biomass or density after two growing seasons, but did reduce its biomass after one growing season. VEGETATION STRUCTURE Height (1 study): One replicated, randomized, paired, controlled study in a salt marsh in the USA found that tilling sediment before planting California cordgrass Spartina foliosa had no significant effect on its height after 1–2 growing seasons. Individual plant size (1 study): One replicated, randomized, paired, controlled study on estuarine sediment in the USA found that the average size of planted salt marsh plants was similar, after 1–2 years, in tilled and untilled plots. Size was reported as an index incorporating plant height and lateral extent. OTHER Survival (1 study): One replicated, randomized, paired, controlled study on estuarine sediment in the USA found that survival rates of planted salt marsh plants were similar, over 1–2 years, in tilled and untilled plots. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3293https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3293Sun, 11 Apr 2021 07:56:47 +0100Collected Evidence: Collected Evidence: Disturb soil/sediment surface before planting trees/shrubs: freshwater wetlandsWe found no studies that evaluated the effects, on vegetation, of disturbing the surface of freshwater wetlands before planting 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%2Fconservationevidencejournal.com%2Factions%2F3294https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3294Sun, 11 Apr 2021 07:57:05 +0100Collected Evidence: Collected Evidence: Disturb soil/sediment surface before planting trees/shrubs: brackish/saline wetlands One study evaluated the effects, on vegetation, of disturbing the surface of brackish/saline wetlands before planting trees/shrubs. The study was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (1 study): One replicated, controlled study on an estuarine mudflat in Australia found that ploughing the substrate before planting grey mangrove Avicennia marina propagules had no significant effect on their height after two growing seasons. OTHER Survival (1 study): One replicated, controlled study on an estuarine mudflat in Australia found that ploughing the substrate before planting grey mangrove propagules had no significant effect on their survival over two growing seasons. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3295https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3295Sun, 11 Apr 2021 07:57:16 +0100Collected Evidence: Collected Evidence: Add upland topsoil before/after planting non-woody plants: freshwater wetlands Three studies evaluated the effects, on vegetation, of adding upland topsoil to freshwater wetlands planted with emergent, non-woody plants. Two studies were in the USA and one was in Canada. One study was in a greenhouse. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Individual species abundance (1 study): One replicated, randomized, paired, controlled study in freshwater trenches in Canada found that adding a mixture of mineral soil and peat to pots of mine tailings before planting water sedge Carex aquatilis typically increased its above-ground biomass two growing seasons later. VEGETATION STRUCTURE Individual plant size (2 studies): One replicated, controlled study in a greenhouse in the USA found that mixing topsoil into pots of mineral soil/compost before planting tussock sedge Carex stricta seedlings typically increased the biomass and number of shoots they developed over three months. However, one replicated, paired, controlled study in a wet meadow restoration site in the USA reported that mixing topsoil into the mineral soil/compost substrate before planting tussock sedge seedlings had no clear effect on the number of shoots they developed over two months. OTHER Survival (1 study): One replicated, randomized, paired, controlled study in freshwater trenches in Canada found that adding a mixture of mineral soil and peat 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%2Fconservationevidencejournal.com%2Factions%2F3296https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3296Sun, 11 Apr 2021 08:11:14 +0100Collected Evidence: Collected Evidence: Add upland topsoil before/after planting non-woody plants: brackish/saline wetlandsWe found no studies that evaluated the effects, on vegetation, of adding upland topsoil 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%2Fconservationevidencejournal.com%2Factions%2F3297https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3297Sun, 11 Apr 2021 08:11:32 +0100Collected Evidence: Collected Evidence: Add upland topsoil before/after planting trees/shrubs: freshwater wetlandsWe found no studies that evaluated the effects, on vegetation, of adding upland topsoil 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%2Fconservationevidencejournal.com%2Factions%2F3298https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3298Sun, 11 Apr 2021 08:11:43 +0100Collected Evidence: Collected Evidence: Add upland topsoil before/after planting trees/shrubs: brackish/saline wetlandsWe found no studies that evaluated the effects, on vegetation, of adding upland topsoil 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%2Fconservationevidencejournal.com%2Factions%2F3299https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3299Sun, 11 Apr 2021 08:11:53 +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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