A Comparison of Qualitative and Quantitative Ecological Assessment Methods of Mangroves in Southwestern Madagascar

Class Year


Document Type

Student Research Paper

Date of Creation

Fall 2012

Department 1

Center for Global Education


Mangroves are unique, tropical, intertidal forests that, among many other important functions, serve as large carbon sinks for the sequestration of atmospheric CO2. This project qualitatively assessed the mangrove forest of Honko Mangrove Conservation and Education (Tulear, Madagascar) in conjunction with Blue Ventures for a proposed Plan Vivo carbon stock project. The qualitative results were then compared with quantitative measurements in order to determine the most effective method of ecological assessment. Sixty-three stands of mangrove forest covering 9.72km2 were identified and mapped. Level of harvest, species composition, density, canopy cover, dominant height, dominant DBH, forest condition and composition were compared between the studies. Qualitative results agreed with quantitative measurements in species composition, dominant height, dominant DBH and forest condition. While there were some differences between level of harvest classifications, density, canopy cover and composition, neither method was determined to be superior to the other. Qualitative and quantitative data both support and correct each other and it is recommended that quantitative data be combined with qualitative observation to avoid oversight in future carbon stock assessments.

This paper was written for the Madagascar: Biodiversity and Natural Resource Management program.