Tropical forests in Southeast Asia is one of the hotspots of biodiversity and carbon stock in the world. However, forest cover has still been decreasing, leading to emissions of carbon dioxide, one of the biggest factors that causes climate change. In recent years, it is said that levels of extreme weather became more intense partly because of climate change and that heavy drought, heat weave, and heavy rain are also observed in tropical regions. These extreme events caused by climate change would affect the ecosystem processes and the environment of tropical forest, and eventually change the biodiversity and forest structure. To minimize the effect of climate change, it is important to monitor tropical rain forest and understand the interaction between atmosphere and biosphere in wide spatial scale.
The previous tropical monitoring system focused on specific areas and concentrated manpower and budget into those areas. In particular, as biodiversity information is based on the local scale monitoring from the forest survey, available information was limited to those specific areas. Furthermore, as the survey covering the whole heterogeneous environment within a tropical rain forest has not been conducted, we still lack the knowledge and the monitoring method on ecosystem functions in tropical forests. To make measures against climate change, we need baseline information and monitoring systems of the biodiversity and ecosystem functions by networking throughout Southeast Asia.
This project intends to develop the methodology for wide spatial scale, long-term, high-resolution forest monitoring system to assess the effect of climate change on the dynamics of tropical forest. In particular, we focus on (1) the forest ecosystem processes that interacts with the atmosphere, (2) the forest canopy structure and its complexity, and (3) the diversity of mammal species. Consequently, by integrating (1) to (3), we will develop the comprehensive evaluation systems of biodiversity and ecosystem functions of tropical forests.
In 1991, NIES concluded a memorandum of understanding (MOU) with our counterpart in Malaysia, Forest Research Institute Malaysia (FRIM) and University of Malay. We started inventory and ecological monitoring of tropical forest in Pasoh Forest Reserve, which is the base of the project. We develop the methodology for species and functional diversity assessment in Southeast Asian tropical forests in Pasoh and also prepare the connection with other areas in the Southeast, such as Borneo, to extend our monitoring studies.
Tropical forests are characterized by their highly heterogeneous canopy structure, which results in a great variation of the light environment within forests. The spatial change of the light environment likely contributes to functional diversity of plants in the forest. Subproject 1 aims to clarify the relationship between the microenvironment and the functional trait of plants. For this purpose, we have set a number of monitoring plots with different microenvironments in the understory in a primary forest, Pasoh, Malaysia. We will then measure physiological and morphological plant traits in each plot. Some traits such as emissions of biogenic volatile organic compounds (BVOC), photosynthetic rate, growth rate, morphology and phenology will be focused on particularly. In addition, we will monitor micro-environmental variables including photon flux density, temperature, humidity, and soil moisture. Based on these measurements, we will develop methods for assessing plant functional diversity using spatial and temporal variables of the microenvironment.
Tropical forests have high canopy of 30?40 meters in height, sometimes with emergent trees of 50m height and complex layer within. This complexity would explain high species diversity of tropical rainforest. Subproject 2 aims to investigate the relationship between canopy complexity and biodiversity. First, we will develop the method of reconstruction of 3D-canopy structure using a low-altitude remote sensing technology and the index that represents canopy complexity. Then we will analyze the relationship between the index and the observed species diversity in the forest. We will also focus on its relation with the environment and functions in the forest floor with subproject 1 and the relationship between vegetation, canopy structure and animal distribution with subproject 3. The effect of tropical canopy structure on biodiversity and ecosystem functions will be comprehensively analyzed.
Rainwater collected inside of tropical forests should contain feces, urine, and skin tissues of wildlife. Thus, it might be possible that DNA extracted from the rain water can be used as DNA templates for metabarcoding approach to identify the species distributed in tropical forests. A similar research, species identification using water, was reported on the species identification of fish. We will modify the technique applied to fish species identification to fit tropical forest environment. The new technique can contribute to simplify biodiversity evaluation of terrestrial wildlife in tropical forests.
|Dr. Manabu ONUMA（Center for Environmental Biology and Ecosystem Studies）|
Dr. Takuya SAITO（Center for Environmental Measurement and Analysis）
Dr. Stephen Joseph ANDREWS （Center for Environmental Measurement and Analysis）
Dr. Yanhong TANG（Center for Environmental Biology and Ecosystem Studies）
Dr. Hajime TOMIMATSU（Center for Environmental Biology and Ecosystem Studies）
Dr. Yayoi TAKEUCHI（Center for Environmental Biology and Ecosystem Studies）
Dr. Nobuko SAIGUSA（Center for Global Environmental Research）
Dr. PINGCHUN（Center for Global Environmental Research）
Dr. Masato HAYASHI（Japan aerospace exploration agency）
Dr. Manabu ONUMA（Center for Environmental Biology and Ecosystem Studies）
＜Counterparts in Forest Research Institute Malaysia＞
Dr. Christine FLETCHER
Dr. Hamdan OMAR
Mr. Azharizan Mohammad NORIZAN
Dr. Samsudin MUSA