We developed a new nitrogen oxide (NO x ) and carbon monoxide (CO) emission inventory for the Los Angeles-South Coast Air Basin (SoCAB) expanding the Fuel-based Inventory for motor-Vehicle Emissions and applied it in regional chemical transport modeling focused on the California Nexus of Air Quality and Climate Change (CalNex) 2010 field campaign. The weekday NO x emission over the SoCAB in 2010 is 620 t d À1 , while the weekend emission is 410 t d À1 . The NO x emission decrease on weekends is caused by reduced diesel truck activities. Weekday and weekend CO emissions over this region are similar: 2340 and 2180 t d À1 , respectively. Previous studies reported large discrepancies between the airborne observations of NO x and CO mixing ratios and the model simulations for CalNex based on the available bottom-up emission inventories. Utilizing the newly developed emission inventory in this study, the simulated NO x and CO mixing ratios agree with the observations from the airborne and the ground-based in situ and remote sensing instruments during the field study. The simulations also reproduce the weekly cycles of these chemical species. Both the observations and the model simulations indicate that decreased NO x on weekends leads to enhanced photochemistry and increase of O 3 and O x (=O 3 + NO 2 ) in the basin. The emission inventory developed in this study can be extended to different years and other urban regions in the U.S. to study the long-term trends in O 3 and its precursors with regional chemical transport models. precursors in the SoCAB may provide comprehensive knowledge of the evolving chemistry and transport KIM ET AL.

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To elucidate the deleterious effects of excessive lead (Pb) on rice (Oryza sativa) cv. Swarn Mansoori, plants were grown in refined sand in complete nutrient solution for 42 days. On the 43rd day, Pb nitrate was superimposed at 1 mM (to rice) for 104 days (till harvest). A set of plants in complete nutrient solution was maintained as control for the same period. Excess Pb reduced the dry weight pronouncedly at harvest (after 104 days of metal supply) when the grain yield also decreased. Lead accumulation reduced the concentrations of chlorophyll in leaves, carotene, sugars, phenols, nonprotein nitrogen, protein, iron, manganese, copper, zinc, Hill reaction activity, and peroxidase activity (one of the anti-oxidative enzymes), but increased the concentrations of sulphur, phosphorus, magnesium (early stage) protein nitrogen, and activity of catalase, ORDER REPRINTS acid phosphatase, and ribonuclease in leaves of rice. Except for slight growth depression and reduction in number and size of leaves, tillers and inflorescence, no other visible symptoms of excessive Pb could be seen before harvesting.

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To identify the detrimental effects of excess copper in radish (Raphanus sativus) cv. Jaunpuri, plants were grown in refined sand at control (0.001) and 0.1 and 0.2 mM (excess) copper (Cu) supplied as Cu sulphate. Previously plants were maintained for 24 days in complete nutrient solution and on the 25th day, excess Cu was superimposed. After 6 days of metal supply, the visible effects of excess Cu appeared as retardation in growth and interveinal chlorosis of young leaves; chlorosis intensified later with the development of irregular brown spots on lamina. Excess Cu not only reduced the size of leaves but also affected adversely the root development. In radish, Cu toxicity decreased the fresh weight, biomass, root weight, concentrations of total and active iron, chlorophyll, activities of antioxidative enzymes catalase (CAT), and peroxidase (POX), starch phosphorylase (ST) and acid phosphatase (AP) with concomitant increase in Cu accumulation in different parts. These effects were more pronounced at 0.2 than 0.1 mM Cu.