03214nam a2200433 4500 20260817171503.0 140198 th eng .b10115808 AIT Thesis no. 830 Lee, Wing-woo Biological indices in water quality studies Bangkok : Asian Institute of Technology, 1975 79 p. Thesis ; no. 830 A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering of the Asian Institute of Technology, Bangkok, Thailand. Thesis (M.Eng.) - Asian Institute of Technology, 1975 The two indices of species diversity, namely, diversity index, d, derived from Information Theory and sequential comparison index, SCI, derived from Theory of Runs were studied by computer simulation and field studies. Artificial communities with different number of species, but same population size and distribution, were used to study the effect of species richness. Results showed that diversity index, d, is better in reflecting species richness. The study of the homogeneity of the two indices using artificial distributions with increasing skewness showed that sequential comparison index, SCI, is preferred to diversity index, d. Regression between 270 sets of values of d and SCI obtained from simulation gives a log- log correlation of 0.984. Field investigation employing benthic macro-invertebrates at 4 different sites showed that both d and SCI can reflect changes in water quality equally well in practice. It was found that community changes in benthic biota may be caused by pollution or other natural changes, and the absolute values of index values are not important, it is the relative changes of index values with respect to time or distance that reflects the environmental stresses. Field experience taught that visual examination of benthos usually gives some indication on the causes of changes. Water quality Biological specimens Pescod, M.B., Chairperson Htun, Maung Nay, Examination Committee Ouano, E.A.R., Examinaion Committee Keidanren, Scholarship Donor Asian Institute of Technology. Thesis ; no. 830 Full-Text http://203.159.5.9/ait-thesis/detail.php?q=B24074 .b10115808 mnait x 260513 1 951012 m a x 0 mnait mnarc mnait 20 40 22 Barcode : 30050003036661 CREATED : 1996-06-06 RECORD # : i11775403 LPATRON : 1014358 LCHKIN : 2003-03-18 # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 1 TOT RENEW : 1 Barcode : 30050160092341 CREATED : 2016-04-22 RECORD # : i12951407 LPATRON : 0 LCHKIN : - # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 0 TOT RENEW : 0 Barcode : 30050121035678 CREATED : 2022-11-24 RECORD # : i13416297 LPATRON : 0 LCHKIN : - # RENEWALS : 0 # OVERDUE : 0 IUSE3 : 0 TOT CHKOUT : 0 TOT RENEW : 0 12407 12407 0 0 0 0 MAIN MAIN mnait 2026-08-17 0 AIT Thesis no. 830 30050003036661 2026-08-17 17:15:03 2 2026-08-17 20 0 0 0 0 MAIN MAIN mnarc 2026-08-17 0 AIT Thesis no. 830 30050160092341 2026-08-17 17:15:03 2026-08-17 40 0 0 0 0 MAIN MAIN mnait 2026-08-17 0 AIT Thesis no. 830 30050121035678 2026-08-17 17:15:03 1 2026-08-17 22