Diversity, abundance and distribution of ground herbs in primary and selectively logged forest of Danum Valley (North Eastern Borneo)

• मुख्य लेखक: David Magintan
• स्वरूप: थीसिस
• भाषा: अंग्रेज़ी; अंग्रेज़ी
• प्रकाशित: 2000
• विषय: SB320-353.5 Vegetables
• ऑनलाइन पहुंच: https://eprints.ums.edu.my/id/eprint/45194/1/24%20PAGES..pdf; https://eprints.ums.edu.my/id/eprint/45194/2/FULLTEXT..pdf

A research project on ground herbs was carried out in Danum Valley Field Centre (North-East Borneo). Studies on herbaceous plants are still very few, particularly in Sabah. Information on ground herbs is crucially important since destruction of their natural habitat is increasing every year. Such studies may increase the understanding of the ecology of ground herbs, which is also important for conservation purposes. The present study on ground herbs was conducted in two habitats of lowland mixed dipterocarp forest. The sites were in primary (PF) and selectively logged forest (SLF). Twenty transects of 5 m x 100 m were placed in each area, which pooled totals of one hectare sampled in each habitat. In each transect, all species of ground herbs were recorded as well as the number of individuals. Five environmental factors were measured: level of disturbance, forest structure, canopy openness, degree of slopes and the leaf litter depth. The relationship between number of species and number of individuals and their environmental factors were analyzed using regression analysis. A total of 187 species were recorded in which 133 were from primary forest and 152 were from selectively logged forest. Nineteen families of angiosperms and 18 families of pteridophytes were found. The percentage of species found in both sites was 59%. The difference in number of species between the two habitats was statistically significant (F1 ,38 = 4.140, P=0.049, ANOVA ). A total of 16,859 individuals were recorded from PF and SLF, of which 9588 individuals were from PF and 7271 from SLF. The difference in number of individuals was not statistically significant (F1, 3a = 2.046, P=0.161, ANOVA ). The regression analysis showed low R2 value and that no factors had a significant effect on the number of species. The R2 value for the regression analysis between number of individual and environmental factors was low (0.119). Selaginella sp. 1 was found to be the most abundant making up 32% of ground herb in both forest types. The most species-rich angiosperm families were the Zingiberaceae with 35 species in total while 56 species of pteridophytes were recorded on both sites. The genus Piper had the highest number of species. The grass Leptaspis cochleata was the only species that occurred in all transects in SLF; in PF forest this grass of the forest was found in 19 of the 20 transects. Common species included Mapania palustris, Globba pendula, Epipremnum falcifolium and Se/aginella sp. 1. The results of this research revealed that selective logging does not destroy the forest completely but, in fact, leads to a more heterogeneous environment and creation of potential new microhabitats for certain species. More intense logging activities could lead to a massive destruction of the forest not just of canopy trees but also of the understorey.