Some aspects of abundance and distribution of zingiberaceae and costaceae in Tabin Wildlife Reserve, Sabah

• Main Author: Januarius Gobilik
• Format: Thesis
• Language: English
• Published: 2002
• Subjects: QK Botany
• Online Access: https://eprints.ums.edu.my/id/eprint/18900/1/Some%20aspects%20of%20abundance.pdf; https://eprints.ums.edu.my/id/eprint/18900/
• Institution: Universiti Malaysia Sabah

A quantitative inventory of Zingiberaceae and Costaceae was carried out in transect plots at Tabin Wildlife Reserve (lWR) to study the ecology of species in these plant families. Systematic keys were also constructed for identification of the gingers in the reserve. Cytotoxicity tests of extracts from three species of Amomum (Zingiberaceae) against brine shrimp were also carried out Forty transects of 100 m by 5 m were studied in two general areas within 2 km of the Lipad Mud Volcano and within 5 km of the Tabin Mud Volcano (the 'Core Area'). Each study area included both primary and logged forests. Twenty transects were laid out in each forest type; eight transects at Upad and 12 transects at Core Area. Nineteen environmental parameters were measured in every transect for ecological study, I.e., abundance and diameter at breast height (DBH) of trees, leaf litter ground cover, frequency of lianas, canopy gaps (CIE index), slope and soil chemistry (pH, loss-on-ignition (L.O.I), texture and cation concentration). Forty-six species from 13 genera of gingers were found in the reserve. However, inside the plots only 36 and 35 species were recorded in primary and logged forests, respectively. These species represented mainly the genera EtJingera, Zingiber and Amomum, with very few from the genera Geocharis, Homstedtia and Elettaria. Only a slight differences in total abundance of gingers was found between primary and logged forests with 1058 and 828 individuals, respectively. Boesenbergia sp. A (31.6%) and Costus speciosus (10.5%) were the dominant species in primary and logged forests, respectively. Study of patterns in the gingers' spacial distribution showed a clumped (contagious) distribution, fitted to log series and log normal distribution models in primary forest and fitted to all abundancy models in logged forest. Diversity of gingers was found to be higher in logged forest and significantly different compared to primary forest. Based on abundance and faithfulness of occurrence, Costus speciosus, Etlingera brevilabrum, and Plagiostachys strobilifera showed a high and significant indicator value for logged and primary forest habitats, respectively. In general, species prefered to primary forest habitat (in TWINSPAN) had negative correlations (Correlation Analysis) with the species that prefered logged forest and with the evironmental variables that characterised it. Multivariate analyses (DCA and CCA) showed that abundance of gingers had a strong correlation to the presence of trees of 2-15 cm DBH, soil pH, proportion of silt and sand and concentration of sodium and magnesium in soil. Multiple Regression Analysis showed magnesium to be the most important predictor to the ginger abundance. In the cytotoxicity test, the three species of Amomum were found to be non-toxic to brine shrimp compared to potassium dichromate (control).