Using portable CO₂ detectors to locate tunnel entrances and nests of the subterranean termite Odontotermes formosanus (Shiraki) in agricultural, forestry, and water conservancy facilities facilitates rapid nest localization and enables scientific control measures.Using a special portable carbon dioxide detection device, the detection area was set up in the serious occurrence plot of O. formosanus. The device was used to detect the ground carbon dioxide concentration, and the concentration anomaly point was excavated to verify the nests and nests entrance of O. formosanus. In addition, the carbon dioxide gas source point at the entrance of the simulated termite nest was set up to determine the concentration diffusion range of carbon dioxide under different wind speeds and wind directions. The device used in the environment with atmospheric wind speed of 0~0.12 m/s can quickly detect abnormal points of carbon dioxide concentration ( termite nest entrance, decayed dead wood or leaves ). After excavation, it is confirmed that the carbon dioxide concentration at the entrance of the ant road is above 0.10%. In simulations of the carbon dioxide gas source, at wind speeds of 0, 0.1, 0.2, 0.4, 0.8, 1.6, and 3.2 m/s, the downwind distance from the source point to where the CO₂ concentration reaches 0.05% is 0.4, 1.0, 1.0, 0.6, 0.4, 0.2, and 0 m, respectively. The distance from the site with a concentration of more than 0.05% in the crosswind direction to the gas source point is 0.4, 0.4, 0.2, 0.2, 0 and 0 m, respectively. The distance between the abnormal site of carbon dioxide concentration and the gas source point is significantly affected by wind direction and wind speed. The portable carbon dioxide detection device can easily detect the abnormal value of carbon dioxide concentration at the entrance of the termite nest in the termite occurrence site. Combined with wind speed, wind direction, measuring point distance, etc., the position of the O. formosanus nests entrance can be quickly detected after eliminating interference factors.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |