Collected Evidence: Collected Evidence: Add perches to electricity pylons to reduce electrocutionA single before-and-after study in Spain found that adding perches did not reduce electrocutions of Spanish imperial eagles Aquila adalberti.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F267https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F267Thu, 19 Jul 2012 16:08:34 +0100Collected Evidence: Collected Evidence: Add salt to ponds to reduce chytridiomycosis One study in Australia found that following addition of salt to a pond containing the chytrid fungus, a population of green and golden bell frogs remained free of chytridiomycosis for at least six months.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F762https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F762Fri, 16 Aug 2013 14:13:19 +0100Collected Evidence: Collected Evidence: Add nutrients to new ponds as larvae food source We found no evidence for the effects of adding nutrients, such as zooplankton, to new ponds on amphibian populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F812https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F812Thu, 22 Aug 2013 15:07:50 +0100Collected Evidence: Collected Evidence: Add specific plants to aquatic habitats We found no evidence for the effects of adding specific plants, such as emergent vegetation, to aquatic habitats on amphibian populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested 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%2F816https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F816Thu, 22 Aug 2013 15:10:49 +0100Collected Evidence: Collected Evidence: Add organic matter One replicated, randomized, controlled study in Brazil found that leaf litter addition increased species richness of young trees. One replicated, controlled study in Costa Rica found leaf litter addition decreased young tree density in artificial forest gaps. Both studies found no effect of litter addition on the density of tree regenerations under intact forest canopy. One replicated, controlled study in Portugal found that adding plant material to the soil surface increased total plant cover. One replicated, controlled study in the USA found mixed effects on cover depending on understory plant group.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1250https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1250Fri, 03 Jun 2016 12:51:42 +0100Collected Evidence: Collected Evidence: Add organic matter after tree planting Two replicated, randomized, controlled studies in the USA found that adding leaf litter or wood-chips before restoration planting increased seedling biomass, but decreased seedling emergence and survival.  Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1258https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1258Mon, 06 Jun 2016 10:36:39 +0100Collected Evidence: Collected Evidence: Add peat to soil We found no studies that evaluated the effects of adding peat to soils to encourage recolonization on shrublands. '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%2F1687https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1687Mon, 23 Oct 2017 09:59:21 +0100Collected Evidence: Collected Evidence: Add sulphur to soil One randomized, replicated, controlled study in the UK found that adding sulphur to the soil of a former agricultural field did not increase the number of heather seedlings in five of six cases. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1691https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1691Mon, 23 Oct 2017 10:40:15 +0100Collected Evidence: Collected Evidence: Add peat to soil (alongside planting/seeding) One replicated, randomized, controlled study in the UK found that adding peat to soil and sowing seed increased the cover of common heather in the majority of cases, compared to seeding alone. One replicated, randomized, controlled study in the UK found that adding peat to soil and sowing seed increased the density of heather seedlings, and led to larger heather plants than seeding alone, but that no seedlings survived after two years. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1705https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1705Mon, 23 Oct 2017 11:54:26 +0100Collected Evidence: Collected Evidence: Add sulphur to soil (alongside planting/seeding) A randomized, replicated, controlled study in the UK found that adding sulphur to soil alongside sowing seeds did not increase heather cover in a majority of cases. One replicated, controlled study in the UK found that adding sulphur and spreading heathland clippings had mixed effects on cover of common heather, perennial rye-grass, and common bent. One randomized, controlled study in the UK found that adding sulphur to soil alongside planting of heather seedlings increased their survival, though after two years survival was very low. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1710https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1710Mon, 23 Oct 2017 13:17:21 +0100Collected Evidence: Collected Evidence: Add root associated bacteria/fungi to introduced plants Two controlled studies (one of which was randomized) in Spain found that adding rhizobacteria to soil increased the biomass of shrubs. One of these studies also found an increase in shrub height. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1716https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1716Mon, 23 Oct 2017 14:00:24 +0100Collected Evidence: Collected Evidence: Add organic fertilizer (before/after planting) We found no studies that evaluated the effects, on peatland vegetation, of adding organic fertilizer to areas planted with peatland 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%2F1827https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1827Tue, 28 Nov 2017 08:51:00 +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%2Fconservationevidencejournal.com%2Factions%2F1841https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F1841Tue, 28 Nov 2017 08:55:55 +0000Collected Evidence: Collected Evidence: Add salt to control problematic plants: freshwater marshesWe found no studies that evaluated the effects, on vegetation, of directly adding salt to control problematic plants 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%2Fconservationevidencejournal.com%2Factions%2F3100https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3100Sun, 04 Apr 2021 09:24:05 +0100Collected Evidence: Collected Evidence: Add salt to control problematic plants: brackish/salt marshes One study evaluated the effects, on vegetation, of directly adding salt to control problematic plants in brackish/salt marshes. The study was in the USA. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (1 study): One replicated, randomized, paired, controlled, before-and-after study in a salt marsh in the USA found that adding salt to control invasive beardgrass Polypogon monspeliensis had no significant effect on the height the dominant native glasswort Salicornia subterminalis. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3101https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3101Sun, 04 Apr 2021 09:24:29 +0100Collected Evidence: Collected Evidence: Add salt to control problematic plants: freshwater swampsWe found no studies that evaluated the effects, on vegetation, of directly adding salt to control problematic plants 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%2Fconservationevidencejournal.com%2Factions%2F3102https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3102Sun, 04 Apr 2021 09:25:07 +0100Collected Evidence: Collected Evidence: Add salt to control problematic plants: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of directly adding salt to control problematic plants 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%2Fconservationevidencejournal.com%2Factions%2F3103https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3103Sun, 04 Apr 2021 09:25:17 +0100Collected Evidence: Collected Evidence: Add sediment: freshwater marshes One study evaluated the effects, on vegetation, of adding sediment to existing freshwater marshes. The study was in the USA. VEGETATION COMMUNITY Overall richness/diversity (1 study): One replicated, randomized, paired, controlled study in the USA reported that adding sediment to freshwater marshes typically reduced plant species richness after one growing season. VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, randomized, paired, controlled study in the USA found that adding sediment to freshwater marshes had no significant effect on total live vegetation biomass after one growing season. Individual species abundance (1 study): The same study found that adding sediment to freshwater marshes had no significant effect on the biomass of most of the dominant herbaceous species after one growing season. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3230https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3230Fri, 09 Apr 2021 14:26:32 +0100Collected Evidence: Collected Evidence: Add sediment: brackish/salt marshes Five studies evaluated the effects, on vegetation, of adding sediment to existing brackish/salt marshes. All five studies were in the USA. Two studies were based on one experimental set-up and two studies were based on another. VEGETATION COMMUNITY Relative abundance (1 study): One replicated, site comparison study in the USA found that salt marshes amended with sediment typically supported a greater relative abundance of smooth cordgrass Spartina alterniflora than degraded marshes after two years, but that this typically remained lower than in natural marshes. Overall richness/diversity (1 study): The same study found that salt marshes amended with sediment typically had greater plant species richness than degraded marshes, and statistically similar richness to natural marshes, after two years. VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, site comparison study in the USA found that salt marshes amended with sediment typically had greater total vegetation cover than degraded marshes, and statistically similar cover to natural marshes, after two years. Individual species abundance (4 studies): Four studies quantified the effect of this action on the abundance of individual plant species. For example, all four studies (including two replicated, randomized, paired, controlled) of salt marshes in the USA found that adding sediment typically increased the abundance of smooth cordgrass Spartina alterniflora, over approximately 1–5 years. This is based on total biomass, density and/or cover. One of the studies reported that adding sediment increased the cover of three other species after one year. VEGETATION STRUCTURE Height (1 study): One replicated, randomized, paired, controlled study in a salt marsh in the USA found that the height of the dominant plant species, smooth cordgrass Spartina alterniflora, did not significantly differ between plots amended with sediment and unamended plots. Height was measured 16 months after sediment amendment began. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3231https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3231Fri, 09 Apr 2021 14:26:47 +0100Collected Evidence: Collected Evidence: Add sediment: freshwater swampsWe found no studies that evaluated the effects, on vegetation, of adding sediment to existing 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%2Fconservationevidencejournal.com%2Factions%2F3232https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3232Fri, 09 Apr 2021 14:27:03 +0100Collected Evidence: Collected Evidence: Add sediment: brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of adding sediment to existing 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%2Fconservationevidencejournal.com%2Factions%2F3233https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3233Fri, 09 Apr 2021 14:27:13 +0100Collected Evidence: Collected Evidence: Add surface mulch before/after planting non-woody plants: brackish/saline wetlands One study evaluated the effects, on vegetation, of mulching brackish/saline wetlands planted with emergent, non-woody plants. The study was in Canada. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, randomized, paired, controlled study in intertidal brackish marshes in Canada found that adding surface mulch after planting wetland herbs typically had no significant effect on total live vegetation biomass, two growing seasons later. Individual species abundance (1 study): The same study found that adding surface mulch increased the cover of one of two planted herb species (creeping alkaligrass Puccinellia phryganodes) but had no significant effect on cover of the other species (estuary sedge Carex subspathacea). Cover was monitored over the second growing season after planting/mulching. VEGETATION STRUCTURE   OTHER Survival (1 study): One replicated, randomized, paired, controlled study in intertidal brackish marshes in Canada found that adding surface mulch had no significant effect on the survival of two of two planted herb species, after two growing seasons. Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3313https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3313Sun, 11 Apr 2021 12:05:55 +0100Collected Evidence: Collected Evidence: Add root-associated fungi to plants before plantingWe found no studies that evaluated the effects – on emergent wetland plants – of adding root-associated fungi 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%2Fconservationevidencejournal.com%2Factions%2F3350https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3350Sun, 11 Apr 2021 16:59:38 +0100Collected Evidence: Collected Evidence: Add sulphur to soil before seeding/planting Two studies examined the effects of adding sulphur to soil before seeding/planting on grassland vegetation. One study was in the UK and one was in the USA. VEGETATION COMMUNITY (2 STUDIES) Overall richness/diversity (1 study): One of two replicated, controlled studies (one of which was randomized and paired) in the UK and USA found that adding sulphur to soil before sowing seeds reduced plant species richness. The other study found no change in overall plant species richness. Native/non-target species richness/diversity (1 study): One replicated, controlled study in the USA found that adding sulphur to soil before sowing seeds did not alter the number of native plant species. VEGETATION ABUNDANCE (2 STUDIES) Overall abundance (1 study): One replicated, randomized, paired, controlled study in the UK found that adding sulphur to soil before sowing seeds reduced overall vegetation cover. Sown/planted species abundance (1 study): One replicated, randomized, paired, controlled study in the UK found that adding low amounts of sulphur to soil before sowing seeds increased the cover of three of six sown species. Native/non-target species abundance (1 study): One replicated, controlled study in the USA found that adding sulphur to soil before sowing seeds did not alter the cover of native plant species. VEGETATION STRUCTURE (0 STUDIES)Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3428https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F3428Mon, 28 Jun 2021 10:48:32 +0100Collected Evidence: Collected Evidence: Add nitrogen and phosphorus to nutrient-limited rivers We found no studies that evaluated the effects of adding nitrogen and phosphorus to nutrient-limited rivers on anguillid eel populations in inland habitats.  ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this intervention during our systematic journal and report searches. Therefore, we have no evidence to indicate whether or not the intervention has any desirable or harmful effects.Collected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F4153https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F4153Mon, 28 Oct 2024 13:46:36 +0000
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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