vegetation

The known moss flora of the small West Indian island Saba (870 m in altitude) consists to date of48 species, while the neighbouring island St. Eustatius (600 m) has 40 species. The two islands have 27 species in common. Widely distributed neotropical species dominate at all elevations, while wide-tropical (i.e. pantropical) species are found mainly at middle elevations (300-600 m). Species with smaller geographical distributions (southern neotropical, Caribbean) are restricted to higher elevations (above 600 m).

An attempt has been made to determine the relation between mosses and the plant communities, encountered along the altitudinal gradient, by calculating “association values”, based on the results of random collecting. Four classes of association values have been distinguished: class A: very characteristic; class B: characteristic; class C: moderately characteristic; and class D: non-characteristic species. It appears that eight plant communities on both islands harbour one or more moderately to very characteristic species. Neckeropsis undulata is the only very characteristic species. It occurs in the evergreen seasonal forest on St. Eustatius. The results are compared with Guadeloupe, Martinique, Puerto Rico, Guyana and Suriname. Finally, a key to the species is included.

This document contains the written guidelines of the monitoring project in the Washington-Slagbaai National park of Bonaire. These monitoring guidelines are a product of BonBèrdè, an independent consultancy business focussed on nature conservation on the island of Bonaire. This document is requested by and written for STINAPA. The monitoring protocol will consist of a background information paper that includes all general information about the protocol as well as factors to be studied in the field. This is the Monitoring protocol. In addition to this document, a field guide is provided. The Field guide can act as a quick check in the field which will provide fast guidelines to the exact measurements of the monitoring itself.

As STINAPA is currently aiming to remove invasive herbivores from the Washington-Slagbaai National park, the goal of the monitoring project is to assess the current state of the ecosystem inside the park and keep measuring the possible changes over time, following the gradual removal of these animals. With the removal of invasive herbivores, the ecosystem viability is expected to increase and result in a positive succession and regeneration of native trees. However, these expectations will have to be measured in order to prove the necessity of invasive species management. The monitoring protocol can provide STINAPA with the tools to measure the changes in the park over time, using indicators of the possible regeneration. These indicators include:

• Vegetation
• Soil
• Fauna

The monitoring protocol will include the exact indicators and factors that can be measured to assess the ecosystem's succession over time. Furthermore, the field guide will provide STINAPA with the manual on how to execute the monitoring in the field. All the methods and proposed actions in these documents are focused to achieve the best results while taking into account that the methods should be practical to implement and replicate by STINAPA personnel.

This report describes a field visit to the Caribbean island of Bonaire aiming at collection of field data on the arid vegetation, which consists largely of dry thorn scrub, cactus scrub and dry tropical forest. Vegetation releves have been amde at 23 sites, among which eight sites that have been surveyed in 1999. Besides 50 short field descriptions have been made as a basis for a land-use map. The report describes how the more than 1000 releves of the Dutch Caribbean islands, which are stored in the vegetation database CACTUS, may be analysed to provide insight in natural processes like vegetation succession and effects of land use, climate change and other factors. Besides, the report contains an advice for the representative Ministry of Agriculture, Nature and Food Quality on the island about the (better) conservation of sites on the limestone terraces with very well developed woodland.

Landscape map that depicts the intersections of biophysical, cultural and aesthetic characteristics, delineating landscape types to which coherent sets of nature-inclusive measures are assigned. This landscape map was developed using clusters of nature-inclusive measures that were spatially located by local experts on a map of Bonaire, in combination with geological, soil , elevation , vegetation , planning and high resolution land cover maps.

See this report for more information.

Bitmap file of a vegetation map by the Nature Conservancy.
Year, author, methodology and objective unknown.

Powerpoint presentation with findings of a 4 week vegetation fieldvisit on Saba:

• what is vegetation (research)?
• historic findings (1956 and 1999)
• current findings (49 repeated plots, 28 additional plots)
• preliminary results for different zonation belts
  • elfin forest (highest zone)
  • elephants ears scrub
  • transitional forest
  • dry tropical forest
  • grasslands, shrubland and coastal cliffs (lower zone)
• conclusions
  • elfin forest far from 'original'
  • zonation 2,3 and 4: no big changes, some expansion of elephant ears, more forest succesion resulting in more closed vegetation and poorer in bio-diversity
  • invasive species are more abundant in the lower zone: coralita, rubber vine,'india grass' and others

Locations of field observations of vegetation. The observations were used as basis for this map as described in this report.

The roughly 300 locations were digitized from paper field forms (1999).

TurboVeg vegetation recordings stored in a SQLLite database (Hennekens and Schaminée, 2001) containing recordings from plot observations. The database contains hundreds of vegetation observations. 

Please contact the DCBD administrator for more information and access.

Below are TurboVeg screenshots from a snapshot of the vegetation observations for Curaçao (including digitized historical observations from Stoffers (1956) and Bokkestijn & Slijkhuis (1987)):

Five of the largest remaining patches of livestock-inaccessible rock vegetation of Curacao, Netherlands Antilles, were described and compared to rock vegetation which has experienced centuries of livestock grazing. Study rocks (maximum diameters: 20-47 m) were located at two sites differing in rock type and altitude. At the St. Christoffelberg site, study rocks were siliceous and at altitudes of 240-310 m while at the Tafelberg site the rocks were of limestone and at altitudes of 35-150 m. The main vascular species on livestock-inaccessible rocks at both sites was Tillandsia flexuosa. a bromeliad. At the St. Christoffelberg, Tillandsia was principally accompanied by the grass Paspalum secans, the orchid Brassavola nodosa and the herb Portulaca venezuelensis, while at the Tafelberg it was principally accompanied by the vine Serjania curassavica. On livestock-accessible rocks Tillandsia ground cover was reduced to insignificant levels and mature plants were virtually eliminated from the population. Grazed vegetations also showed reduced vascular cover and were principally dominated by the annual grass Aristida adscencionis (St. Christoffelberg site only), the prickly pear Opuntia wentiana and the shrubby tree Acacia tortuosa. None of these weedy species, all of which are widely distributed on the island, were of any significance in ungrazed rock vegetations. It is hypothesized that Tillandsia-dominated ground cover may have been a common feature of the rock vegetation of the island prior to the introduction of livestock.

Vegetation map of St.Maarten. Source unknown.