Application of plant physiological ecology and laser raindrop spectroscopy to the monitoring of tropical rainforests in Hainan

2024-05-23 09:05:05 DianjiangHK 9

Hainan tropical rain forest is a well-preserved continental island tropical rain forest with concentrated distribution, many types and types in China. It is a representative of island tropical rain forest, a treasure house of tropical biodiversity and genetic resources, and an ecological security barrier of Hainan Island, with national representation and global protection significance.


Hainan Tropical Rainforest National Park covers and connects five national nature reserves of Wuzhishan, Yingge Ling, Jianfengling, Bawangling and Xiaoluo Mountain, four provincial nature reserves of Limu Mountain, Monkey Rh Range, Jiashi RH Range and Aoxian RH Range, and four national forest parks of Jianfengling, Bawangling Ling, Xiaoluo Mountain and Limu Mountain.

Jianfengling is a huge gene bank of natural species. 2,286 species of wild vascular plants have been discovered, among which 32 species are national key protected plants, such as Cephalotaxus grandis, Youdan, Polei and Pericarpium Citri Reticulatae. There are 400 species of vertebrates, among which there are 8 species of national first-class protected animals, including round-nosed monitor lizard, pangolin, civet cat, civet cat, Hainan partridge, Hainan peacock pheasant, South Sea bream, yellow-billed egret, etc., and 2222 species of insects have been identified, among which the national first-class protected one is Papilio aurea. The forest coverage rate of Jianfengling is 98%, and the vegetation types are mainly tropical semi-deciduous monsoon forest and tropical evergreen monsoon forest, which is the most complete plant landscape system in Hainan Island. After visiting Jianfengling, United Nations experts believe that it is the most ideal place for the first study of the United Nations "Man and Biosphere" program, with complete types, which can be used for research in all disciplines.

In order to explore the changes of tree growth, stem flow, hydrological water quality and rainfall in tropical rain forest, the National Field Scientific Observation and Research Station of Jianfengling Forest Ecosystem in Hainan, Institute of Tropical Rain Forest, Chinese Academy of Forestry, introduced the tree growth and stem flow monitoring system, hydrological water quality monitoring system and laser raindrop spectrometer of DIANJIANG TECH, and continuously and scientifically monitored the changes of stem, stem flow, hydrological water quality and rainfall of selected trees in the sample plot in real time, thus injecting a contribution to the study of tropical rain forest ecosystem.

The tree growth and stem flow monitoring system contains multiple perimeter growth measurement sensors for high-precision and continuous measurement of plant perimeter changes, the signal of which is received via a metal rope covering the measuring object.Multiple stem flow sensors are used to monitor the fluid flow status of trees. When working, two probes are inserted into different parts of the trunk. The upper probe is heated by the flow, and the temperature difference between the two probes is formed. As the flow rises, it takes away the heat and the temperature difference between the two probes becomes smaller. There is a functional relationship between temperature difference and liquid flow.The liquid flow rate is calculated by measuring the temperature difference.Different liquid flows produce different temperature differences, and the sensor senses the resulting tiny voltage to provide flow calculation data.

The Rain Forest Hydrology and Water quality monitoring system is equipped with multiple sensors that measure water level, flow rate, PH, conductivity, water temperature, REDOX potential, turbidity, dissolved oxygen, BOD, COD, TOD and chlorophyll.

Laser raindrop spectrometer is a modern optical measurement system based on laser technology. Infrared laser is emitted horizontally through the detection head, and then gathered on the photodiode at the receiving end after passing through the atmosphere. When the precipitation particles fall through the measurement area, the laser intensity received by the photodiode will change. The digital signal processor (DSP) will calculate the size, rate and type of particles through this change, and can measure various types of precipitation at all wind speeds from quiet winds to hurricanes, accurately and comprehensively recording and analyzing precipitation types, precipitation and precipitation distribution.