Sampling Methods of Vegetation Investigation in a Tropical Rain Forest at Bawangling Nature Reserve,Hainan

Abstract:

Sampling techniques of vegetation study on tropical forest were examined with the help of table manipulation function and neighbourhood analysis function of GIS (geographic information system). An example was presented based on the survey data from a tropical ravine rain forest community at Bawangling National Nature Reserve on Hainan Island. The results indicated that the often-used species-area curve could not determine minimum area for the ravine forest, i.e. minimum area was much larger than 5 000 m²，while according to the importance value-area curve，minimal area for ravine forest was 4 000 m². Closest individual method was adopted to study plotless sampling．Results showed that the minimal point number for species-point number curve was 119， and that for importance value-point num ber curve was 280．Species-individual curve indicates that the individual number needed for investigation should be multiplied fourfold，if we want to obtain doubling species number．