Collected Evidence: Collected Evidence: Log/remove trees within forests: effects on non-vascular plants Two of three studies (including one replicated, paired sites study) in Australia, Norway and Sweden found logging trees in forests decreased epiphytic plant abundance and fern fertility. One found mixed effects depending on species.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1270https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1270Fri, 10 Jun 2016 09:37:49 +0100Collected Evidence: Collected Evidence: Log/remove trees within forests: effects on mature trees Three of seven studies (including two replicated, controlled studies) in Bolivia, Central African Republic, China, Finland, Malaysia, Uganda and the USA found that logging trees in forests decreased the density and cover of trees. Two found it increased tree density and two found no effect of logging on tree density. Three of six studies (including one replicated, randomized, controlled study) in Bolivia, Canada, China, Kenya, Malaysia and the USA found that logging trees in forests increased tree size. Two found it decreased tree size and one found no effect of  logging on tree size. Two of four studies (including one paired site study) in Bolivia, China, Mexico and Papua New Guinea found that logging trees in forests decreased tree species richness and diversity. One study found it increased diversity and one found no effect of logging on tree species diversity. One replicated, controlled study in Canada found that logging trees in forests increased tree mortality rate.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1271https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1271Mon, 13 Jun 2016 08:55:36 +0100Collected Evidence: Collected Evidence: Log/remove trees within forests: effects on young trees One replicated controlled study in Canada found that logging trees in forests increased the density of young trees. One replicated controlled study in Costa Rica found mixed effects on the density of young trees.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1272https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1272Mon, 13 Jun 2016 09:18:50 +0100Collected Evidence: Collected Evidence: Log/remove trees within forests: effects on understory plants Five of ten studies (including four replicated, randomized, controlled studies) in Bolivia, Canada, India and the USA found that logging trees in forests increased the density and cover of understory plants. Five studies found no effect or mixed effects. Four of seven studies (including one replicated, randomized, controlled study) in Australia, Canada and the USA found that logging trees in forests increased species richness and diversity of understory plants. Three studies found no effect.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1273https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1273Mon, 13 Jun 2016 09:29:47 +0100Collected Evidence: Collected Evidence: Lobby, campaign or demonstrate to protect peatlands Two studies evaluated the effects of lobbying/campaigning/demonstrating for peatland protection on knowledge, behaviour, peatland habitats or peatland vegetation. Both studies reported effects, on unspecified peatlands, of the same campaign in the UK. Peatland protection (2 studies): Two studies in the UK reported that the area of protected peatland increased following pressure from a campaign group. Behaviour change (1 study): One study in the UK reported that following pressure from a campaign group, major retailers stopped buying compost containing peat from important peatland areas and horticultural companies began marketing peat-free compost. Attitudes/awareness (1 study): One study in the UK reported that following campaign pressure, garden centres and local governments signed peatland conservation agreements. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1849https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1849Tue, 28 Nov 2017 10:29:16 +0000Collected Evidence: Collected Evidence: Maintain bat roosts in road/railway bridges and culverts Two studies evaluated the effects of maintaining bat roosts within road bridges on bat populations. One study was in Ireland and one in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (2 STUDIES)      Use (2 studies): One before-and-after study in Ireland found that a maternity colony of Daubenton’s bats continued to roost in a road bridge over a river in similar numbers after crevices were retained during repair work. One review in the USA found that when bat roosts were maintained during bridge replacement works, Yuma myotis and Mexican free-tailed bats recolonised most roosts in similar numbers to before the works, but pallid bats did not return. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1966https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1966Tue, 04 Dec 2018 18:03:09 +0000Collected Evidence: Collected Evidence: Limit, cease, or prohibit sediment discard during aggregate extraction We found no studies that evaluated the effects of limiting, ceasing, or prohibiting sediment discard during aggregate extraction on subtidal benthic invertebrate populations.   ‘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%2Fwww.conservationevidence.com%2Factions%2F2073https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2073Mon, 21 Oct 2019 14:19:53 +0100Collected Evidence: Collected Evidence: Locate aquaculture systems in already impacted areas We found no studies that evaluated the effects of locating aquaculture systems in already impacted areas on subtidal benthic invertebrate populations.   ‘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%2Fwww.conservationevidence.com%2Factions%2F2187https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2187Tue, 22 Oct 2019 12:56:48 +0100Collected Evidence: Collected Evidence: Locate aquaculture systems in areas with fast currents We found no studies that evaluated the effects of locating aquaculture systems in areas with fast currents on subtidal benthic invertebrate populations.   ‘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%2Fwww.conservationevidence.com%2Factions%2F2188https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2188Tue, 22 Oct 2019 12:57:27 +0100Collected Evidence: Collected Evidence: Locate aquaculture systems in vegetated areas We found no studies that evaluated the effects of locating aquaculture systems in vegetated locations on subtidal benthic invertebrate populations.   ‘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%2Fwww.conservationevidence.com%2Factions%2F2189https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2189Tue, 22 Oct 2019 12:58:02 +0100Collected Evidence: Collected Evidence: Locate artificial reefs near aquaculture systems (and vice versa) to act as biofilters We found no studies that evaluated the effects of locating artificial reefs near aquaculture systems to act as biofilters on subtidal benthic invertebrate populations.   ‘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%2Fwww.conservationevidence.com%2Factions%2F2196https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2196Tue, 22 Oct 2019 13:07:49 +0100Collected Evidence: Collected Evidence: Locate artificial reefs near aquaculture systems to benefit from nutrient run-offs Two studies examined the effects of locating artificial reefs near aquaculture systems to benefit from nutrient run-offs on subtidal benthic invertebrate populations. One study was in the Gulf of Aqaba (Israel and Jordan), and one in the Mediterranean Sea (Spain).   COMMUNITY RESPONSE (1 STUDY) Overall community composition (1 study): One controlled study in the Mediterranean Sea found that an artificial reef located under aquaculture cages had similar invertebrate community composition to artificial reefs located at sites without aquaculture cages. POPULATION RESPONSE (1 STUDY) Overall abundance (1 study): One controlled study in the Gulf of Aqaba found that an artificial reef located at an aquaculture site had similar invertebrate biomass growing on it compared to an artificial reef located at a site without aquaculture cages. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2260https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2260Wed, 23 Oct 2019 10:51:01 +0100Collected Evidence: Collected Evidence: Limit, cease or prohibit the use of sonars We found no studies that evaluated the effects of limiting, ceasing or prohibiting the use of sonars on marine and freshwater mammal populations. ‘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%2F2902https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2902Mon, 08 Feb 2021 16:13:57 +0000Collected Evidence: Collected Evidence: Limit, cease or prohibit the use of underwater explosives We found no studies that evaluated the effects of limiting, ceasing or prohibiting the use of underwater explosives on marine and freshwater mammal populations. ‘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%2F2903https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2903Mon, 08 Feb 2021 16:14:39 +0000Collected Evidence: Collected Evidence: Lower water level to restore degraded freshwater marshes Two studies evaluated the effects, on vegetation, of lowering the water level to restore degraded freshwater marshes. One study was in the USA and one was in Canada. VEGETATION COMMUNITY Overall extent (1 study): One before-and-after study of a lakeshore marsh in the USA reported that following a drawdown of water levels, emergent vegetation coverage increased in areas that were previously open water. Community types (1 study): One replicated, controlled, before-and-after study of freshwater marshes in Canada reported changes in the area of some vegetation classes over three years of partial drawdown. There was a temporary increase in coverage of dead vegetation at the expense of some live vegetation classes. Two classes – horsetail-dominated and bur-reed-dominated – had greater coverage after three years of drawdown than before. VEGETATION ABUNDANCE   VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3030https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3030Wed, 31 Mar 2021 15:20:12 +0100Collected Evidence: Collected Evidence: Lower water level to restore degraded brackish/salt marshesWe found no studies that evaluated the effects, on vegetation, of lowering the water level to restore degraded brackish/salt 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%2F3031https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3031Wed, 31 Mar 2021 15:20:22 +0100Collected Evidence: Collected Evidence: Lower water level to restore degraded freshwater swampsWe found no studies that evaluated the effects, on vegetation, of lowering the water level to restore degraded 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%2F3032https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3032Wed, 31 Mar 2021 15:20:38 +0100Collected Evidence: Collected Evidence: Lower water level to restore degraded brackish/saline swampsWe found no studies that evaluated the effects, on vegetation, of lowering the water level to restore degraded 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%2F3033https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3033Wed, 31 Mar 2021 15:20:55 +0100Collected Evidence: Collected Evidence: Lower water level to restore/create freshwater marshes from other land uses Two studies evaluated the effects, on vegetation, of lowering the water level to restore/create freshwater marshes from other land uses or habitat types. One study was in the USA and one was in the Netherlands. VEGETATION COMMUNITY Overall extent (1 study): One replicated, before-and-after study of a freshwater wetland in the USA reported that following a drawdown of water levels, emergent vegetation coverage increased in areas that were previously open water. VEGETATION ABUNDANCE Overall abundance (1 study): One before-and-after study at the edge of a freshwater lake in the Netherlands reported that following a drawdown of the lake water level, vegetation cover developed in areas that were previously open water. Cover varied between years and elevations. VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3202https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3202Fri, 09 Apr 2021 07:46:42 +0100Collected Evidence: Collected Evidence: Lower water level to restore/create brackish/salt marshes from other land usesWe found no studies that evaluated the effects, on vegetation, of lowering the water level to restore/create brackish/salt marshes from other land uses or habitat types.   ‘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%2F3203https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3203Fri, 09 Apr 2021 07:47:14 +0100Collected Evidence: Collected Evidence: Lower water level to restore/create freshwater swamps from other land usesWe found no studies that evaluated the effects, on vegetation, of lowering the water level to restore/create freshwater swamps from other land uses or habitat types.   ‘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%2F3204https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3204Fri, 09 Apr 2021 07:47:30 +0100Collected Evidence: Collected Evidence: Lower water level to restore/create brackish/saline swamps from other land usesWe found no studies that evaluated the effects, on vegetation, of lowering the water level to restore/create brackish/saline swamps from other land uses or habitat types.   ‘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%2F3205https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3205Fri, 09 Apr 2021 07:47:43 +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%2Fwww.conservationevidence.com%2Factions%2F3275https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3275Sat, 10 Apr 2021 17:04:37 +0100Collected Evidence: Collected Evidence: Lobby/campaign/demonstrate to protect marshes or swamps One study evaluated the effects, on vegetation or human behaviour, of lobbying/campaigning/demonstrating to protect marshes or swamps. The study was in Brazil. VEGETATION COMMUNITY   VEGETATION ABUNDANCE   VEGETATION STRUCTURE   OTHER Human behaviour (1 study): One study in Brazil reported after lobbying local and national governments, a wetland complex was designated as a sustainable development reserve (rather than being strictly protected) and a sustainable development research institute was created. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3394https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3394Mon, 12 Apr 2021 12:11:04 +0100Collected Evidence: Collected Evidence: Maintain dams or water impoundments One study evaluated the effects of maintaining dams or water impoundments on reptile populations. This study was in the USA. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (0 STUDIES) BEHAVIOUR (1 STUDY) Use (1 study): One replicated, before-and-after study in the USA found that after sediment removal, or dam maintenance along with sediment removal, one water impoundment was still used by Sonoran mud turtles and a second was not used. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3667https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3667Fri, 10 Dec 2021 11:22:04 +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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