Title : " A Comparison of Efficiency of Two Artificial Substrate Samples, Used in Water Quality Mornitoring in Northern Thailand"

Researcher : W.A.H.P. Guruge and P. Chantaremongkol

Office of Researcher : BIOLOGY


The two kinds of Artificial substrate samples (ASS) compared were, wooden box (WB) and wire mesh cage (WMC) filled with stones. The two ASS were kept during both dry and wet seasons in sites in four different water body viz. stream (4), river(2), irrigation canal(2) and sewage canal(2) sites. ASS were retrieved after 2 months and collected macroinvertebrates were identified upto family level. Efficiency of two ASS were determined by comparing number of individuals and families colonized in two ASS.

In dry season 211.18 and 476.6 individual/m2 were collected from WMC and WB respectively. In wet season, 677.2 and 564.1 individual/m2 were collected from WMC and WB respectively. In WMC 48 and 51 families colonized in dry and wet season respectively. In WB, 53 and 60 families had colonized during dry and wet season respectively. Irrespective of site and season, mean number of animals found in WB sampler was significantly different from WMC(p< 0.05) and WB sampler recorded highest mean number of individual/m2 (439.94). Considering the taxa richness ther is no significant difference in efficiency of colonization between WB and WMC. There is a remarkable ASS by macroinvertebrates.

Presented at : The 1st International Conference on Water Resources Management In Intermontane Basins, Chiang Mai, 2-6 February 1999.