Evaluation on The Change of Water Quality and Survival Rate of Mangrove Seedling within Silvicultural Pond at Semarang City during Early Dry Season

Abstract

Water quality and survival rate of mangrove seedling planted within silvofishery pond are vulnerable to seasonal climate change. Early dry season usually provide initial change on climate change such as lowering rain intensity, increasing light intensity and lower water tide. This research aimed to study the change of water quality and evaluate survival rate of mangrove seedling planted in early dry season. This research was conducted for 4 months from March to June 2015. Observations was conducted in April (1st period) and June (2nd period). Observation on the water quality parameters including temperature, turbidity, salinity, pH and DO. While survival rate observed in this research including survival of Avicennia marina and Rhizophora mucronata which were utilized as mangrove species integrated in silvicultural pond. Analysis result showed there were significant difference on the water quality for temperature, turbidity, salinity and pH, while DO was not significantly different. Observations of water quality showed changes from first observation to second observation. Average temperature decreased from 34.24 °C to 31.38 °C, turbidity decreased from 379.74 NTU to 313.01 NTU, salinity increased from 22.0 ‰ to 31.0 ‰, pH increased from 7.49 to 9.26, while DO increased from 6.56 mg/l to 6.99 mg/l. Evaluation on the survival rate of mangrove seedling showed only 16.67% of Avicennia marina survive while Rhizophora mucronata had higher survival rate with 31.48%. The result indicate that early dry season generate the change of water quality and effect to survival of mangrove seedlings.