Rice paddy fields

Na is a very reactive substance which is never found free in nature. It is not generally used as an incendiary agent as such but, because of its tendency not only to float on w, but also to ignite spontaneously in contact with it, it may be added to napalm for use against river targets or enemy positions in rice paddy fields or in snow (Ref 7, p 103 Ref 4, pp 28-29)... 

Sampling sediment and water in rice paddy fields and adjacent water bodies... 

Data on weather conditions, especially temperature and rainfall (temporal distribution and intensity) in the study area are essential for the evaluation of the dissipation data. It is very important to understand the water balance in the paddy field as accurately as possible when calculating the rate of outflow. Records of changes in water temperature and sediment temperature are also helpful for modeling the behavior of a chemical in the rice paddy field. 

Denier van der Gon HAC, Kropff MJ, van Breemen N, Wassmann R, Lantin RS, Adu-na E, Croton TM, van Laar HH. Optimizing grain yields reduces CH4 emissions from rice paddy fields. P. Natl. Acad. Sci. USA. 2002 99 12021-12024. 

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