Arana Ildefonso Liñero, Ojeda Sol, Amaro María Elena
Departamento de Biología Marina, Instituto Oceanográfico de Venezuela, Universidad de Oriente, Cumaná, Venezuela.
Rev Biol Trop. 2013 Mar;61(1):59-73.
Meiofauna organisms that play an important role in the trophic ecology of soft bottom benthos, have short life cycles and they respond quickly to disturbance and pollution. The present study shows the spatio-temporal variation ofsubtidal meiofauna (metazoans passing a 500im sieve but retained on meshes of 40-63micro m) in four shallow subtidal stations. Samples were taken in the sandy beach of San Luis, in the Northeastern coast of Venezuela, from October 2005 until September 2006. For this, three replicate sediment core samples (4.91cm2), were collected monthly to a depth of 10cm into the sediment, and preserved in 6% formalin stained with rose Bengal. Specimens of 14 meiofaunal groups (Foraminifera excluded) were collected, being the nematodes, ostracods and harpacticoid copepods the most abundant. Monthly density was comprised between 64 and 503ind./10cm2, and mean density of stations between 173 and 449ind./10cm2. There is a trend of low densities from October to February (end of the rainy season until the middle of the dry season). The San Luis beach control of the meiofaunal community is shared by climatic conditions and by the biology of the species found. The meiofauna mean density in San Luis beach (263ind./10cm2) was low when compared to other studies in tropical areas.
小型底栖生物在软底质底栖生物的营养生态学中发挥着重要作用，它们生命周期短，对干扰和污染反应迅速。本研究展示了四个浅海潮下带站点潮下带小型底栖生物（能通过500微米筛网但被40 - 63微米筛网截留的后生动物）的时空变化。样本于2005年10月至2006年9月在委内瑞拉东北海岸圣路易斯的沙滩采集。为此，每月采集三个重复的沉积物柱状样本（4.91平方厘米），采集深度达沉积物10厘米处，并保存在用孟加拉玫瑰红染色的6%福尔马林中。采集了14个小型底栖生物类群的标本（不包括有孔虫），其中线虫、介形虫和猛水蚤为最丰富的类群。每月密度在64至503个个体/10平方厘米之间，各站点平均密度在173至449个个体/10平方厘米之间。10月至2月（雨季结束至旱季中期）存在低密度趋势。圣路易斯海滩小型底栖生物群落受气候条件和所发现物种的生物学特性共同影响。与热带地区的其他研究相比，圣路易斯海滩小型底栖生物的平均密度较低。
