Journal of Civil and Environmental Engineering

We developed a model correlating Advanced Very High Resolution Radiometer (AVHRR)-based Temperature Condition Index (TCI) and Vegetation Condition Index (VCI) with potato yield in Bangladesh. Weekly TCI and VCI Indices for 1993–2005 along with official potato yield statistics were used for model development. We found a strong correlation between inter annual variation in potato yield and TCI and VCI during the critical period of potato growth (vegetative phase and tuber initiation), mid-December to mid-January. Principal component regression (PCR) was used to construct a model to predict potato yield as function of TCI and VCI. The model explained about 75% of yearto- year variation in potato yield. Remote sensing offers valuable and readily obtainable information on potato yield well in advance of harvest.

Aerobic spherical granules were observed in zeolitic dual-layer intermittent percolating ï»¿filters ï»¿treating domestic septic tank effluent. The diameter of the granules ranged from 0.05 to 0.5 mm and when they predominate in the biofilms the mean SVI value was of 54 ml g-1 instead of 232 ml g-1 when they were absent. Flow behavior in these filters was characterized by the dimensionless Reynolds number. The values obtained (40