Dinh Thi Hai Van <br/><br/>
Assessment of ozone effects on selected crops in Asia :  case study with selected crops in the northern Vietnam 

 - Pathum Thani, Thailand :  Asian Institute of Technology,  2005 
 - 88 leaves :  ill. 
 - Thesis ;  no. EV-05-8 .
 - Asian Institute of Technology.  Thesis ;  no. EV-05-8 .
<br/><br/> A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Environment, Resources and Development 
<br/><br/>Thesis (M.Sc.) - Asian Institute of Technology, 2005 
<br/><br/> High concentrations of around-level ozone adversely effect human health, property. forestry and agricultural production. Elevated ozone concentrations have caused reduction in plants growth and productivity of agricultural crops. This study examines effects of ozone on two selected agricultural crops using open-top chambers (OTCs) experiments in I-lanoi. Vietnam. The rice (R18) and peanuts (L14) species were exposed to ozone during the flowering stage. The species were grown in similar fertilization's conditions to that of typical farming conditions. Five ozone treatments were adopted: non-filtered air (ambient condition as control treatment). non-filtered air supplemented with 32 ppb. 62ppb. 85ppb and 113ppb of ozone. The rice chambers v\-ere exposed to these ozone treatments for 25 days and peanut chambers were exposed for 29 days with 7 hours each day.  Data from OTCs experiments were used to derive relationship between yield and ozone exposure. "l'he exposure index of accumulated exposure over a threshold ozone concentration of 40 ppb (AO f40) was used in this study. Ozone exposure caused reductions in the hiomass and yields of the selected aoricultural species.  In the case of rice. in treatment 5, with the highest ozone concentration and AOT40 of 12.77Sppb.h. the grain and straw yields were reduced by approximately 480ro and 39'0. respectively. in comparison with the control treatment. For peanuts. the seed yield and aboveground biomass in treatment 5 were 49" %% and 23%. respectively. lower than that in the control treatment. I fence. it was concluded that ozone adversely affects the `gro\\th rate and yield, of the rice and peanuts. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Ozone--Asia<br/>Ozone--Vietnam<br/>Crops--Effect of air pollution on--Asia<br/>Crops--Effect of air pollution on--Vietnam