Morphometric analysis of cervical vertebrae in some marine and land mammals

Bones or skeletal remains can be used to answer a number of questions related to species, sex, age or cause of death. However, studies involving vertebrae have been limited as most were performed on skulls or long bones. Here, we have stated the hypothesis that the morphometry of cervical vertebrae can be used for species identification and body size estimation among marine and land mammals. The cervical vertebrae from eight and 14 species of marine and land mammals were used to collect morphometric data. Cluster dendrogram, principal component analysis, discriminant analysis and linear regression were used to analyse the data. The results indicate that, based on an index of C4 to C7, there were 13 out of 22 species for which identity could be correctly predicted in 100% of the cases. The correlations between cervical vertebrae parameters (height, width and length of centrum) in marine (average R^2 = 0.87, p < .01) and land (average R^2 = 0.51, p < .01) mammals were observed. These results indicate that vertebral morphometrics could be used for species prediction and verification of body weight in both marine and land mammals.     

Evaluation of environmental impact of the raised-bed-dike (Rong Chin) system along the Tha Chin river in Suphan Buri-Nakhon Pathom Provinces,Thailand

Vegetable cultivation on an embankment surrounded by water (raised-bed-dike system, Thai name rong chin) along the Tha Chin (Suphan Buri) river in the Suphan Buri and Nakhon Pathom Provinces was surveyed. The system was introduced by Chinese immigrants to produce vegetables in the river delta. The rong chin system in this area produced mainly Chinese kale, chili, bitter gourd, yard-long bean, taro, and sweet potato, while fruit trees and flowers were seldom cultivated, because of the flooding of the river in the rainy season. The amounts of nitrogen and phosphorus applied into field soils as fertilizers were far higher than those recovered in the harvested vegetables, indicating that only a limited portion of the nutrients was taken up by the crops and that part of the nutrients remained in the soils and in the dike water. Periodical flooding promoted leaching of the accumulated nutrients in the fields. Analyses of the soils and river waters revealed that phosphorus had started to accumulate in the environment, whereas only a small amount of nitrogen was detected in the river, canal, and dike waters, presumably because of the active uptake of nitrogen by biomass and denitrification.