Study

Wetland cover types and plant community changes in response to cattail-control activities in the Palo Verde Marsh, Costa Rica

  • Published source details Trama F.A., Rizo-Patron F.L., Kumar A., González E., Somma D. & McCoy C.M.B. (2009) Wetland cover types and plant community changes in response to cattail-control activities in the Palo Verde Marsh, Costa Rica. Ecological Restoration, 27, 278-289

Actions

This study is summarised as evidence for the following.

Action Category

Control problematic plants (multiple interventions): freshwater marshes or swamps

Action Link
Marsh and Swamp Conservation

Physically damage problematic plants: freshwater marshes

Action Link
Marsh and Swamp Conservation

Use prescribed fire to control problematic plants: freshwater marshes

Action Link
Marsh and Swamp Conservation
  1. Control problematic plants (multiple interventions): freshwater marshes or swamps

    A controlled study in 1987–2004 in an ephemeral freshwater marsh in Costa Rica (Trama et al. 2009) reported that controlling invasive southern cattail Typha domingensis with multiple interventions reduced the total vegetated area and vegetation cover, but increased plant species richness. Unless specified, statistical significance was not assessed. After approximately 15–17 years, a managed plot (where cattail had been controlled) contained less live vegetation overall than an unmanaged plot. This was true for the total area of live vegetation (managed: 28–85%; unmanaged: 98–100%) and cover of live vegetation along transects (managed: 35–91%; unmanaged: 88–100%). Abundance varied across seasons. The managed plot also contained less cattail – both in terms of the total area (managed: 9–24% of plot; unmanaged: 63–66% of plot) and cover along transects (managed: 5–10%; unmanaged: 75–100%). Finally, the managed plot contained more plant species in total (managed: 59; unmanaged: 20) and had significantly greater plant species richness (managed: 13; unmanaged: 4 species/300 m2 transect). Methods: Two 80-ha plots were established in a cattail-dominated marsh. Cattail stands were managed in one of the plots: with multiple experimental interventions from 1987 (including cutting by hand, mowing, physical damage, grazing and burning, alone and in combination) then by physical damage alone from September 2002 (driving over it in a tractor with large paddle wheels). Water supply was also restored to both plots in July 2002. Vegetation stands were mapped from aerial photographs or satellite images taken in November 2002 (wet season) and March 2003 (dry season). Detailed vegetation surveys, along six 25 x 2 m transects/plot, were carried out between August 2003 and July 2004.

    (Summarised by: Nigel Taylor)

  2. Physically damage problematic plants: freshwater marshes

    A controlled, before-and-after study in 1998–2004 in an ephemeral freshwater marsh in Costa Rica (Trama et al. 2009) reported that crushing and burning stands of invasive southern cattail Typha domingensis reduced the total vegetated area and vegetation cover, but increased plant species richness. Unless specified, statistical significance was not assessed. In the wet season before intervention, live vegetation stands covered 98–99% of the study plots. In a managed plot, this dropped to 68% after five months (wet season) then 23% after eight months (dry season). Over the same period, the coverage of southern cattail stands dropped from 61–62% to 52%, then to 7%. In an unmanaged plot, coverage remained ≥98% for live vegetation and 63–66% for cattail. After 11–22 months, the managed plot had lower cover of live vegetation, along transects, than the unmanaged plot (managed: 17–90%; unmanaged: 88–100%). The same was true for cattail cover (managed: 5–38%; unmanaged: 75–100%). Meanwhile, the managed plot contained more plant species, both overall (managed: 61; unmanaged: 20 species/plot) and within transects (managed: 12; unmanaged: 4 species/300 m2). Methods: Two 80-ha plots were established in a cattail-dominated marsh. From September 2002, cattail stands in one of the plots were damaged when wet (by driving over them in a tractor with large paddle wheels) and/or burned when dry. The study does not distinguish between the effects of these interventions. Both plots had been rewetted in July. Vegetation stands were mapped from aerial photographs or satellite images taken before (December 1998) and after (November 2002, March 2003) intervention. Detailed vegetation surveys, along six 25 x 2 m transects/plot, were carried out between August 2003 and July 2004. This study used the same marsh as (5), but a different experimental set-up.

    (Summarised by: Nigel Taylor)

  3. Use prescribed fire to control problematic plants: freshwater marshes

    A controlled, before-and-after study in 1998–2004 in an ephemeral freshwater marsh in Costa Rica (Trama et al. 2009) reported that burning and crushing stands of invasive southern cattail Typha domingensis reduced the total vegetated area and vegetation cover, but increased plant species richness. Unless specified, statistical significance was not assessed. In the wet season before intervention, live vegetation stands covered 98–99% of the study plots. In a managed plot, this dropped to 68% after five months (wet season) then 23% after eight months (dry season). Over the same period, the coverage of southern cattail stands dropped from 61–62% to 52%, then to 7%. In an unmanaged plot, coverage remained ≥98% for live vegetation and 63–66% for cattail. After 11–22 months, the managed plot had lower cover of live vegetation, along transects, than the unmanaged plot (managed: 17–90%; unmanaged: 88–100%). The same was true for cattail cover (managed: 5–38%; unmanaged: 75–100%). Finally, the managed plot contained more plant species, both overall (managed: 61; unmanaged: 20 species/plot) and within transects (managed: 12; unmanaged: 4 species/300 m2). Methods: Two 80-ha plots were established in a cattail-dominated marsh. From September 2002, cattail stands in one of the plots were burned when dry and/or crushed when wet (by driving over them in a tractor with large paddle wheels). The study does not distinguish between the effects of these interventions. Both plots had been rewetted in July. Vegetation stands were mapped from aerial photographs or satellite images taken before (December 1998) and after (November 2002, March 2003) intervention. Detailed vegetation surveys, along six 25 x 2 m transects/plot, were carried out between August 2003 and July 2004.

    (Summarised by: Nigel Taylor)

Output references

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