Accumulation and degradation of organic matter in bottom soil of tiger prawn (Penaeus monodon Fabricius) intensive culture ponds
1991
Niwooti Whangchai
Highest organic matter content was found at 20 cm depth and the lowest organic matter content was found at the surface. Significant correlation was also observed between organic matter and soil pH (r=-0.9429, -0.8874), organic matter and clay content (r=0.8122, 0.8626) and organic matter and percentage of water exchange (r=-0.8663, -0.8177). Decreasing rates of organic matter content of ponds bottom soil outside mangrove area in three different depths (surface, 10 cm and 20 cm) in a period of 4 months were 2.99, 10.06 and 8.75 %/month comparing to 2.61, 6.64 and 3.36 %/month of the ponds constructed in mangrove area. The highest decreasing rate occured at 10 cm. depth of both areas and the lowest decreasing rate of both areas occured at the surface. Degradation rate of organic matter of ponds outside mangrove area bottom soil during 30 days period of drying the depth of surface, 10 cm depth and 20 cm depth was 9.31, 9.28 and 2.77 %/10 days, respectively, comparing to 9.58, 9.00 and 9.15 %/10 days of degradation rate of organic matter of the ponds constructed in mangrove area. The decreasing rate of organic matter of surface soil and the soil at 10 cm depth of both area were not significantly different. The lowest degradation rate of organic matter of the soil outside mangrove area was observed at 20 cm depth.
显示更多 [+] 显示较少 [-]