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2.
PLoS One ; 12(12): e0188564, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29261694

RESUMO

Coastal ecosystems and the livelihoods they support are threatened by stressors acting at global and local scales. Here we used the data produced by the Caribbean Coastal Marine Productivity program (CARICOMP), the longest, largest monitoring program in the wider Caribbean, to evidence local-scale (decreases in water quality) and global-scale (increases in temperature) stressors across the basin. Trend analyses showed that visibility decreased at 42% of the stations, indicating that local-scale chronic stressors are widespread. On the other hand, only 18% of the stations showed increases in water temperature that would be expected from global warming, partially reflecting the limits in detecting trends due to inherent natural variability of temperature data. Decreases in visibility were associated with increased human density. However, this link can be decoupled by environmental factors, with conditions that increase the flush of water, dampening the effects of human influence. Besides documenting environmental stressors throughout the basin, our results can be used to inform future monitoring programs, if the desire is to identify stations that provide early warning signals of anthropogenic impacts. All CARICOMP environmental data are now available, providing an invaluable baseline that can be used to strengthen research, conservation, and management of coastal ecosystems in the Caribbean basin.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Estresse Fisiológico , Região do Caribe , Conservação dos Recursos Naturais , Conjuntos de Dados como Assunto , Humanos , Salinidade , Água do Mar , Temperatura
3.
Rev Biol Trop ; 53 Suppl 1: 105-15, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-17465150

RESUMO

Maintaining regional competitiveness and economic viability for Port Bustamante - Kingston Harbour, Jamaica, required improved accessibility to "Post Panamax" (too large to pass through the Panama Canal) container vessels. Removal of the northern portion of the shallow coral reef at Rackham's Cay, which was partially obstructing the western end of the east ship channel, was proposed. This aesthetically valuable reef was used by local fishermen and comprises part of the declared Palisadoes - Port Royal Protected Area. The proposal to transplant certain of the benthic species was advanced to mitigate loss of viable reef components. Between December 2001 and February 2002, sixty thousand items, consisting of reef building massive and branching corals; gorgonians; urchins (Diadema and Tripneustes spp.) and Thalassia meristems were relocated. During dredging, sedimentation rates from suspended solids in the water column were 0.003 g/cm(2)/day at the control site and 0.008 g/cm(2)/day at the dredge site. Coral cover in the relocation area increased from 15% to 20% while bare substrate decreased from 27% to 21%. This paper documents the mitigation required; some factors controlling the ecology of Rackham's Cay reef, the methodology of the relocation process; and the level of post-dredging survivorship of relocated corals. Political and economic realities of some proposed developments often override ecological considerations. Transplantation of important marine benthic species although time consuming, technically challenging, and expensive, may be one way for developers and ecologists to achieve sometimes disparate goals. This project cost US$1.7 million. The "items" moved were neither unique nor endemic and remain vulnerable to natural and anthropogenic impacts. This project increased public awareness and interest regarding the ecological and economic importance of reef ecosystems. It is anticipated that future coastal and inland developments will benefit from the lessons taught by these mitigative interventions.


Assuntos
Antozoários/crescimento & desenvolvimento , Conservação dos Recursos Naturais , Ecossistema , Adaptação Psicológica , Animais , Aquicultura/métodos , Monitoramento Ambiental , Sedimentos Geológicos/análise , Jamaica , Nefelometria e Turbidimetria , Densidade Demográfica , Dinâmica Populacional , Água do Mar/química
4.
PLoS One ; 9(3): e90600, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24594732

RESUMO

The CARICOMP monitoring network gathered standardized data from 52 seagrass sampling stations at 22 sites (mostly Thalassia testudinum-dominated beds in reef systems) across the Wider Caribbean twice a year over the period 1993 to 2007 (and in some cases up to 2012). Wide variations in community total biomass (285 to >2000 g dry m(-2)) and annual foliar productivity of the dominant seagrass T. testudinum (<200 and >2000 g dry m(-2)) were found among sites. Solar-cycle related intra-annual variations in T. testudinum leaf productivity were detected at latitudes > 16°N. Hurricanes had little to no long-term effects on these well-developed seagrass communities, except for 1 station, where the vegetation was lost by burial below ∼1 m sand. At two sites (5 stations), the seagrass beds collapsed due to excessive grazing by turtles or sea-urchins (the latter in combination with human impact and storms). The low-cost methods of this regional-scale monitoring program were sufficient to detect long-term shifts in the communities, and fifteen (43%) out of 35 long-term monitoring stations (at 17 sites) showed trends in seagrass communities consistent with expected changes under environmental deterioration.


Assuntos
Biota , Monitoramento Ambiental/estatística & dados numéricos , Hydrocharitaceae/crescimento & desenvolvimento , Biomassa , Região do Caribe , Monitoramento Ambiental/métodos , Dinâmica Populacional
5.
Artigo em Inglês | MEDLINE | ID: mdl-11912050

RESUMO

Stress protein (heat shock protein, hsp70) response is involved in protecting organisms from the detrimental effects of environmental stressors, such as radiation and high temperatures. Tropical chitons can briefly tolerate high temperatures. However, they minimize the effects of elevated temperature during daylight hours and periods of tidal air exposure by remaining in rocky intertidal microhabitats along the shoreline of tropical waters. To study the natural variability of the hsp70 level, individuals of the polyplacophoran species Acanthopleura granulata Gmelin, 1791 were sampled every 4 h on two days in spring of 1999. Hsp70 levels were separately measured in the supernatant of the intestinal tract and foot muscle homogenates with a standardized immunoassay. The hsp70 level in the intestinal tract was highest in the early morning, decreased during the mid-morning hours and dropped to a comparatively low level in the afternoon, before increasing again during the night. The stress protein level in the foot muscle followed the daily air temperature curve with a time delay of a few hours, reaching the highest level in the afternoon and the lowest level in the early morning. The stress protein response can be interpreted as a sign of heat tolerance development and may play a role in allowing A. granulata to tolerate the temperature variability typical of its intertidal habitat.


Assuntos
Ritmo Circadiano/fisiologia , Meio Ambiente , Proteínas de Choque Térmico HSP70/metabolismo , Moluscos/metabolismo , Animais , Ecossistema , Imunoensaio , Mucosa Intestinal/metabolismo , Músculos/metabolismo , Temperatura , Fatores de Tempo , Clima Tropical
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