Melo S, Bozelli R L, Esteves F A
Laboratório Plâncton, CPBA, Instituto Nacional de Pesquisas da Amazônia, Manaus, AM 69060-001, Brazil.
Braz J Biol. 2007 Aug;67(3):475-83. doi: 10.1590/s1519-69842007000300012.
Spatial and temporal variability of the phytoplankton community in the tropical coastal Imboassica lagoon, an environment naturally isolated from the ocean by a narrow sandbar, was analysed every two weeks for 19 months by sampling three sites. During this study, the lagoon received direct input of marine water three times, resulting in remarkable salinity, nutrient concentrations and phytoplankton biomass variations in both temporal and spatial aspects. The phytoplankton biomass presented relatively low values ranging, on average, from 0.54 mg x L(-1) in the station closest to the sea (station 1) to 1.34 mg x L(-1) in the station close to a macrophyte bank (station 3). Diatoms and cryptomonads dominated in stations 1 and 2 (located relatively close to station 1, yet receiving the runoff of domestic sewage), and euglenoids, cryptomonads and dinoflagellates at station 3. Stations 1 and 2 usually presented the same dominant species but station 2 presented a higher phytoplankton biomass. On the other hand, station 3 showed more similar results concerning phytoplankton biomass with station 2, however the dominant species were usually different. The high fluctuations of salinity and the reduced nutrient availability are pointed out as the main factors structuring the dynamics of the phytoplankton community at the Imboassica lagoon.
在热带沿海的因博阿西卡泻湖，这是一个通过狭窄沙洲与海洋自然隔离的环境，对浮游植物群落的时空变异性进行了为期19个月的分析，每两周在三个站点进行一次采样。在这项研究中，泻湖三次接受了海水的直接输入，导致盐度、营养物质浓度和浮游植物生物量在时间和空间上都出现了显著变化。浮游植物生物量呈现出相对较低的值，平均而言，在最靠近大海的站点（站点1）为0.54毫克/升，在靠近大型植物滩的站点（站点3）为1.34毫克/升。硅藻和隐藻在站点1和站点2（相对靠近站点1，但接收生活污水径流）占主导地位，而裸藻、隐藻和甲藻在站点3占主导地位。站点1和站点2通常呈现相同的优势物种，但站点2的浮游植物生物量更高。另一方面，站点3在浮游植物生物量方面与站点2的结果更为相似，然而优势物种通常不同。盐度的高波动和营养物质可用性的降低被指出是构建因博阿西卡泻湖浮游植物群落动态的主要因素。
