Development of measuring and monotoring system for CO_2 flux in remote fields using mobile phone

本研究的目的是开发偏远地区的CO_2通量测量与监测系统。该系统由丙烷燃烧驱动的小型直流发电机和移动电话组成，无需交流线路和电话线即可在远程测量现场使用。利用开发的软件，将田间CO_2通量测量数据通过手机传输到实验室计算机，并在实验室计算机中自动转换为数据库(每日数据)，然后在计算机CRT上自动显示各种图形和表格，并以打印机列出。所开发的系统还具有以下特点：(1)实现了自动、可靠的长期测量。(2)数据记录器、传输设备和其他必要设备可放置在靠近测量杆或塔的小夏格箱内。(3)任何实验室都可以在线传输数据；(4)除传感器外，该系统的价格约为200万日元。我们还开发了专门的空气采样和数据处理单元。通过该装置的使用，使鲍文比法测量CO_2通量所需的两个高度之间的CO_2差的精确和长期测量成为可能。该系统帮助我们了解测量数据和测量设备的情况，从而减少我们访问现场进行维护工作的次数。在5个不同的站点进行了总共20个月的试运行，结果表明，在偏远站点进行可靠、长期、连续的CO_2通量测量是可能的。

The aim of the research is to develop measuring and monitoring system for CO_2 flux in remote fields. The system is composed of small DC generator which is driven by propane gas conbustion and mobile phpone, then the system is possible to use in remote measurement sites without AC line and telephone line. By the use of the software developed, CO_2 flux measurement data in the fields are transmitted to laboratory computers through mobile phone, converted automatically as a data base (a daily data) in laboratory computer, and then different kinds of graphs and tables are shown automatically on the computer CRT and listed by printer.The other characteristics of the developed system are as follows : (1) automatic and reliables longterm measurements are possible. (2) the data logger, transmitting apparatuses and other necessary devices are possible to keep in small hagar box placed near the measurement pole or tower. (3) on line data transmitting is possible from any laboratories, (4) the price for the system except for sensors is about two million Yen.We also developed a special air sampling and data processing unit. By the use of the unit, the precise and longterm measurement of CO_2 difference between two heights necessary for CO_2 flux measurement by Bowen ratio techniqu became possible. The system helps us to see what is happning in the measured data and measurement eqipments, and then it allowed us to decrease visitting the sites for maintenance work. It was shown by the test runs of total 20 monthes at five different sites that reliable, longterm and continuous measurement of CO_2 flux is possible in remote sites.