Conservation Evidence: Evidence Data

Collected 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%2Fconservationevidencejournal.com%2Factions%2F2952https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2952Mon, 22 Mar 2021 13:41:02 +0000Collected Evidence: Collected Evidence: Abandon cropland: allow brackish/saline marshes or swamps to recover without active interventionWe found no studies that evaluated the effects, on vegetation, of abandoning cropland with the expectation that brackish/saline marshes or swamps would recover spontaneously. ‘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%2F2953https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2953Mon, 22 Mar 2021 13:41:20 +0000Collected Evidence: Collected Evidence: Flood cropland when fallow to conserve freshwater marshes One study evaluated the effects, on freshwater marsh vegetation, of flooding cropland during fallow seasons or years. The study was in Brazil. VEGETATION COMMUNITY Community composition (1 study): One replicated, site comparison study in Brazil found that flooding rice fields during their fallow period affected the overall community composition of wetland plants, but that the nature of the effect depended on when fields were surveyed. Overall richness/diversity (1 study): The same study found that flooding rice fields during their fallow period had no significant effect on wetland plant species richness per site and per survey, although fewer species were recorded in the flooded fields over the year of the study. VEGETATION ABUNDANCE VEGETATION STRUCTURECollected Evidencehttps%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2954https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2954Thu, 25 Mar 2021 13:44:32 +0000Collected Evidence: Collected Evidence: Flood cropland when fallow to conserve brackish/salt marshesWe found no studies that evaluated the effects, on brackish/salt marsh vegetation, of flooding cropland during fallow seasons or years. ‘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%2F2955https%3A%2F%2Fconservationevidencejournal.com%2Factions%2F2955Thu, 25 Mar 2021 13:54:21 +0000