Collected Evidence: Collected Evidence: Add woody debris to forestsA randomised, replicated, controlled study from Australia found that brown treecreeper numbers were higher in plots with large amounts of dead wood added, compared to control plots or those with less debris added.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F344https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F344Sat, 28 Jul 2012 20:38:38 +0100Collected Evidence: Collected Evidence: Adopt certification One replicated, site comparison study in Ethiopia found that the risk of deforestation was lower in certified than uncertified forests. One controlled, before-and-after trial in Gabon found that when logging intensity was taken into account although tree damage did not differ, changes in above-ground biomass were smaller in certified than in uncertified forests.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1150https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1150Tue, 17 May 2016 16:23:09 +0100Collected Evidence: Collected Evidence: Adopt community-based management to protect forests Two studies from Ethiopia and Nepal (including one replicated, before-and-after, site comparison) found that forest cover increased more in community-managed forests than in forests not managed by local communities. One replicated, site comparison study in Colombia found that deforestation rates in community-managed forests did not differ from deforestation rates in forests that were not managed by local communities, or in uninhabited national parks.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1152https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1152Wed, 18 May 2016 14:58:54 +0100Collected Evidence: Collected Evidence: Adopt ecotourism We found no evidence for the effects of adopting ecotourism on forests. '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%2Fwww.conservationevidence.com%2Factions%2F1173https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1173Thu, 19 May 2016 09:46:59 +0100Collected Evidence: Collected Evidence: Adopt continuous cover forestry We found no evidence for the effects of adopting continuous cover forestry on forests. '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%2Fwww.conservationevidence.com%2Factions%2F1179https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1179Thu, 19 May 2016 10:33:07 +0100Collected Evidence: Collected Evidence: Adopt conservation grazing of woodland We captured no evidence for the effects of adopting conservation grazing of woodland. '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%2Fwww.conservationevidence.com%2Factions%2F1192https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1192Thu, 19 May 2016 11:53:01 +0100Collected Evidence: Collected Evidence: Adopt protected species legislation (impact on forest management) We found no evidence of the effects of adopting protected species legislation on forests. '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%2Fwww.conservationevidence.com%2Factions%2F1201https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1201Thu, 19 May 2016 13:21:26 +0100Collected Evidence: Collected Evidence: Add lime to the soil to increase fertility One replicated, randomized controlled study in the USA found that adding lime increased vegetation cover.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1249https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1249Fri, 03 Jun 2016 12:48:10 +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%2Fwww.conservationevidence.com%2Factions%2F1250https%3A%2F%2Fwww.conservationevidence.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%2Fwww.conservationevidence.com%2Factions%2F1258https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1258Mon, 06 Jun 2016 10:36:39 +0100Collected Evidence: Collected Evidence: Add lime to the soil after tree planting One of two replicated, randomized, controlled studies in the USA found that adding lime before restoration planting decreased the survival of pine seedlings. The other study found no effect of adding lime on planted oak seedling growth.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1259https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1259Mon, 06 Jun 2016 10:42:49 +0100Collected Evidence: Collected Evidence: Add lime (before/after planting) Six studies evaluated the effects on peatland vegetation of liming areas planted with peatland plants. Four studies involved fen plants, one involved bog plants and one involved peat swamp plants. Two of the studies were in greenhouses/nurseries. Survival (2 studies): One replicated, controlled study in the Netherlands reported that liming typically reduced survival of planted fen herbs after two growing seasons. One replicated, randomized, paired, controlled study in Sweden found that liming increased survival of planted fen mosses over one growing season. Growth (3 studies): Two controlled, before-and-after studies found that liming did not increase growth of planted peatland vegetation. Liming reduced or had no effect on Sphagnum moss growth in bog pools in the UK, and reduced growth rates for the majority of peat swamp tree seedlings in a nursery in Indonesia. One replicated, controlled, before-and-after study in Sweden found that liming increased growth of planted fen mosses. Cover (2 studies): One replicated, randomized, paired, controlled, before-and-after study in a fen in Sweden found that liming increased cover of sown mosses. However, one replicated, randomized, paired, controlled study in a bog in Canada found that liming plots sown with fen vegetation fragments had no effect on total vegetation, vascular plant or bryophyte cover. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1825https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1825Tue, 28 Nov 2017 08:50:30 +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%2Fwww.conservationevidence.com%2Factions%2F1841https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1841Tue, 28 Nov 2017 08:55:55 +0000Collected Evidence: Collected Evidence: Abandon cropland: allow freshwater marshes or swamps to recover without active intervention Four studies evaluated the effects, on vegetation, of abandoning cropland with the expectation that freshwater marshes or swamps would recover spontaneously. There was one study in each of Spain, South Korea, China and Japan. The studies involved former rice fields, soybean fields or pastures. VEGETATION COMMUNITY Community composition (2 studies): Two site comparison studies in South Korea and Japan reported that the overall plant community composition in abandoned cropland became more like natural swamps and/or marshes over time. Overall richness/diversity (2 studies): One site comparison study on a floodplain in Japan found that pastures abandoned for 5–25 years contained a higher richness of vascular, wetland plant species than pastures that remained in use. One study in South Korea simply reported the number of plant species in abandoned rice paddies increased over time. Characteristic plant richness/diversity (1 study): One site comparison study on a floodplain in Japan found that pastures abandoned for 5–25 years typically contained more marsh-indicator and swamp-indicator species than pastures that remained in use. VEGETATION ABUNDANCE Overall abundance (2 studies): One site comparison study in China found that vegetation biomass in abandoned soybean fields was lower than in natural wet meadows after three years, similar to natural wet meadows after six years, and higher than in natural wet meadows after 12 years. One study in Spain simply quantified the peak biomass and density of vegetation in rice fields abandoned for up to six years. Biomass, but not density, increased with time since abandonment. VEGETATION STRUCTURE Height (1 study): One site comparison study in China found that soybean fields abandoned for 3–12 years contained vegetation of a similar height to natural wet meadows. Diameter/perimeter/area (1 study): One site comparison study in South Korea reported that rice fields abandoned for 10 years contained thinner-stemmed Japanese alder Alnus japonica than mature alder forests. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2952https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2952Mon, 22 Mar 2021 13:41:02 +0000Collected Evidence: Collected Evidence: Abandon aquaculture facilities: allow brackish/saline marshes or swamps to recover without active intervention One study evaluated the effects, on vegetation, of abandoning aquaculture facilities with the expectation that brackish/saline marshes or swamps would recover spontaneously. The study was in Costa Rica. VEGETATION COMMUNITY Community composition (1 study): One site comparison study in Costa Rica reported that after 14 years, an abandoned shrimp pond contained the same four tree species as a nearby natural mangrove forest. VEGETATION ABUNDANCE Tree/shrub abundance (1 study): One site comparison study in Costa Rica reported that after 14 years, an abandoned shrimp pond contained a greater density of trees than a nearby natural mangrove forest. VEGETATION STRUCTURE Height (1 study): One site comparison study in Costa Rica reported that after 14 years, an abandoned shrimp pond had a shorter tree canopy than a nearby natural mangrove forest. Basal area (1 study): The same study reported that the basal area of trees was smaller in an abandoned shrimp pond, after 14 years, than in a nearby natural mangrove forest. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2983https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2983Thu, 25 Mar 2021 15:27:56 +0000Collected Evidence: Collected Evidence: Actively manage water level: freshwater swamps Two studies evaluated the effects, on vegetation, of active water level management in freshwater swamps. Both studies were in the USA. VEGETATION COMMUNITY Overall richness/diversity (1 study): One before-and-after study of a swamp/marsh in the USA found that overall plant diversity was higher in the autumn following a managed flood/drawdown than in the autumn before. VEGETATION ABUNDANCE Tree/shrub abundance (1 study): One site comparison study of floodplain swamps in the USA found that an artificial flood had no significant effect on tree seedling density in a low and very wet swamp, but increased tree seedling density in a drier swamp higher on the floodplain. Individual species abundance (1 study): One before-and-after study of a swamp/marsh in the USA reported mixed responses of individual plant species’ cover to active water level management. However, the study found that cover of the dominant woody species, Pacific willow Salix lucida, was higher in the autumn following a managed flood/drawdown than in the autumn before. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3040https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3040Thu, 01 Apr 2021 10:03:39 +0100Collected Evidence: Collected Evidence: Add inorganic fertilizer before/after planting trees/shrubs: freshwater wetlands Two studies evaluated the effects, on vegetation, of adding inorganic fertilizer to freshwater wetlands planted with trees/shrubs. Both studies were in the USA. VEGETATION COMMUNITY                  VEGETATION ABUNDANCE   VEGETATION STRUCTURE Height (1 study): One replicated, paired, controlled study in the USA found that adding fertilizer had no significant effect, after two years, on the height of tree saplings planted into floating peat bags. Diameter, perimeter, area (1 study): The same study found that adding fertilizer had no significant effect, after two years, on the diameter of two of three tree species planted into floating peat bags. However, fertilized pond apple Annona glabra saplings had thicker stems than unfertilized saplings. OTHER Growth (1 study): One replicated, randomized, controlled study in the USA found that adding fertilizer increased the growth rate of baldcypress Taxodium distichum seedlings planted into a marsh. This was true for both diameter and height growth. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3306https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3306Sun, 11 Apr 2021 08:57:33 +0100Collected Evidence: Collected Evidence: Add below-ground organic matter before/after planting trees/shrubs: freshwater wetlands One study evaluated the effects, on vegetation, of adding below-ground organic matter to freshwater wetlands planted with trees/shrubs. The study was in the USA. VEGETATION COMMUNITY Community composition (1 study): One replicated, randomized, paired, controlled study in a created wetland in the USA found that amongst plots planted with tree seedlings, those amended with large amounts compost contained a plant community characteristic of drier conditions, three years later, than the community in unamended plots. The lowest compost dose had no significant effect on this outcome. Overall richness/diversity (1 study): The same study found that amongst plots planted with tree seedlings, those amended with a large amount of compost had lower plant species richness and diversity, three years later, than unamended plots. Lower compost doses had no significant effect on either outcome. VEGETATION ABUNDANCE Overall abundance (1 study): One replicated, randomized, paired, controlled study in a created wetland in the USA found that amongst plots planted with tree seedlings, those amended with compost supported a similar overall vegetation biomass, three years later, to unamended plots. VEGETATION STRUCTURE Individual plant size (1 study): One replicated, randomized, paired, controlled study in a created wetland in the USA found that birch Betula saplings were larger, three years after planting seedlings, in plots amended with large amounts of compost than in unamended plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3310https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3310Sun, 11 Apr 2021 09:51:11 +0100Collected Evidence: Collected Evidence: Add below-ground organic matter before/after planting trees/shrubs: brackish/saline wetlands One study evaluated the effects, on vegetation, of adding below-ground organic matter to brackish/saline wetlands planted with trees/shrubs. The study was in Brazil. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Survival (1 study): One replicated, randomized, controlled study in a coastal swamp in Brazil reported that adding manure to plots planted with tree seedlings had mixed effects on their survival over three years, depending on the species of tree and dose of manure. Growth (1 study): The same study reported that adding manure to plots planted with tree seedlings had mixed effects on their growth over three years, depending on the species of tree and dose of manure. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3311https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3311Sun, 11 Apr 2021 09:51:23 +0100Collected Evidence: Collected Evidence: Add surface mulch before/after planting non-woody plants: freshwater wetlands One study evaluated the effects, on vegetation, of mulching freshwater wetlands planted with emergent, non-woody plants. The study was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Herb abundance (1 study): One replicated, randomized, paired, controlled study in floodplain swamps in Australia found that mulching with woodchips before planting native understory herbs either increased or had no significant effect on their overall cover, one year later. Individual species abundance (1 study): The same study found that mulching with woodchips before planting native understory herbs reduced the cover of one problematic species (common reed Phragmites australis) one year later, but had no significant effect on another (reed canarygrass Phalaris arundinacea). VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3312https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3312Sun, 11 Apr 2021 12:05:44 +0100Collected Evidence: Collected Evidence: Add surface mulch before/after planting trees/shrubs: freshwater wetlands One study evaluated the effects, on vegetation, of mulching freshwater wetlands planted with trees/shrubs. The study was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Tree/shrub abundance (1 study): One replicated, randomized, paired, controlled study in floodplain swamps in Australia found that mulching with woodchips before planting native shrubs had no significant effect on their overall cover, one year later. Individual species abundance (1 study): The same study found that mulching with woodchips before planting swamp gum Eucalyptus camphora seedlings had no significant effect on swamp gum cover, one year later. Mulching reduced cover of the problematic herb species in one of two swamps, but had no significant effect in the other. VEGETATION STRUCTURE Height (1 study): One replicated, randomized, paired, controlled study in floodplain swamps in Australia found that planted swamp gum Eucalyptus camphora seedlings reached a similar height, after one year, in mulched and unmulched plots. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3314https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3314Sun, 11 Apr 2021 12:06:05 +0100Collected Evidence: Collected Evidence: Add cover other than mulch before/after planting non-woody plants: freshwater wetlands One study evaluated the effects, on vegetation, of adding cover other than mulch to freshwater wetlands planted with emergent, non-woody plants. The study was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Tree/shrub abundance (1 study): One replicated, randomized, paired, controlled study in floodplain swamps in Australia found that covering plots with plastic or jute mats before planting native understory herbs increased their overall cover, one year later. Individual species abundance (1 study): The same study found that covering plots with plastic or jute mats before planting native understory herbs reduced the cover of two problematic herb species, one year later. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3316https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3316Sun, 11 Apr 2021 12:19:16 +0100Collected Evidence: Collected Evidence: Add cover other than mulch before/after planting trees/shrubs: freshwater wetlands One study evaluated the effects, on vegetation, of adding cover other than mulch to freshwater wetlands planted with trees/shrubs. The study was in Australia. VEGETATION COMMUNITY   VEGETATION ABUNDANCE Tree/shrub abundance (1 study): One replicated, randomized, paired, controlled study in floodplain swamps in Australia found that covering plots with plastic or jute mats before planting native shrubs had no significant effect on their overall cover, one year later. Individual species abundance (1 study): The same study found that covering plots with plastic or jute mats before planting swamp gum Eucalyptus camphora seedlings had no significant effect on swamp gum cover, one year later. Covering plots with mats also reduced cover of two problematic herb species. VEGETATION STRUCTURE                                          Height (1 study): One replicated, randomized, paired, controlled study in floodplain swamps in Australia found that planted swamp gum Eucalyptus camphora seedlings reached a similar height, after one year, in covered and uncovered plots. Covers were plastic or jute mats. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3318https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3318Sun, 11 Apr 2021 12:19:45 +0100Collected Evidence: Collected Evidence: Add cover other than mulch before/after planting trees/shrubs: brackish/saline wetlands One study evaluated the effects, on vegetation, of adding cover other than mulch to brackish/saline wetlands planted with trees/shrubs. The study was in Mexico. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Growth (1 study): One controlled study on a sandflat in Mexico reported that planted black mangrove Avicennia germinans seedlings grew more in height, over six months, when shaded with black mesh than when not shaded. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3319https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3319Sun, 11 Apr 2021 12:19:58 +0100Collected Evidence: Collected Evidence: Add woody debris to landscapes Six studies evaluated the effects of adding woody debris to landscapes on reptile populations. Three studies were in Australia, two were in the USA and one was in Indonesia. COMMUNITY RESPONSE (3 STUDIES) Richness/diversity (5 studies): Four of five studies (including four replicated, randomized, controlled studies) in the USA, Indonesia and Australia found that areas with added woody debris had similar richness and diversity or richness or of reptiles, rare reptiles and snakes and lizards compared to areas with no added debris. The other study found that areas with added woody debris had higher reptile species richness than areas with no added debris. POPULATION RESPONSE (6 STUDIES) Abundance (6 studies): Two of six replicated studies (including four randomized, controlled studies) in Australia, Indonesia and the USA found that areas with added woody debris had a higher abundance of reptiles than areas with no added debris. Three studies found that areas with woody debris had a similar abundance of reptiles and snakes and lizards compared to areas with no added debris. The other study found that pastures with added timber had lower abundance of rare reptile species compared to pastures without timber, but that in pastures with added timber, reptile abundance was higher after 15 months than after 12 months. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3718https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3718Mon, 13 Dec 2021 15:33:28 +0000
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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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