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Two kinds of near-stoichiometric LiNbO 3 crystals (SLN11 and SLN19) were grown by a flux pulling method from stoichiometric melt with addition of 11mol%K 2 O and 19mol%K 2 O, respectively. Compared with the congruent melting LiNbO 3 , the ultraviolet absorption edges of two crystals shift towards shorter wavelengths, and the locations of the OH -infrared absorption band have obvious change and the bandwidths become greatly narrower. From these experimental results, the Li 2 O contents are determined indirectly to be about 49.6mol% for SLN11 and 49.9mol% for SLN19, respectively. The Li 2 O content in SLN19 is very close to the ideal value of 50mol%. The coercive fields of two crystals were measured by the poling method at room temperature. A linear relationship between the Li 2 O content and the coercive field was fitted.

Salt-affected soils are extensively present and constitute about 7% of total land surface. However, our knowledge about greenhouse gas (GHG) turnover between the atmosphere and the saline soils is very limited. In order to evaluate the potential of GHG consumption in saline soils, we measured gas fluxes of carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O) from the soil surface to the atmosphere under saline-alkaline mudflat and various community types in the Yellow River Delta in China. In general, the emissions of GHG of different ecosystems showed a unique peak diurnal pattern, with the peak at 13:00 h and the lowest value at 07:00 h. The CH 4 and N 2 O emission of different ecosystems followed the order: saline-alkaline mudflat . T. chinensis . S. salsa . P. australis, while the CO 2 emission followed the order: T. chinensis . P. australis . S. salsa . saline-alkaline mudflat. On the whole, saline-alkaline mudflat and different vegetations acted as CO 2 and N 2 O source in spring, while saline-alkaline mudflat and P. australis communities acted as CH 4 source and CH 4 sink, respectively. However, T. chinensis and S. salsa communities acted as CH 4 sink before 12:00 h and CH 4 source after 12:00 h. Although measurements of the CO 2 , CH 4 and N 2 O fluxes were taken simultaneously, CH 4 and N 2 O fluxes were strongly correlated with soil moisture, temperature and electrical conductivity, while no significant correlation was found between CO 2 flux with above environmental factors. These results probably suggest that factors other than soil temperature, moisture and salinity exerted a larger impact on fluxes than on CH 4 and N 2 O release and/or that there were not enough samples for CO 2 flux measurements because of its higher spatial and temporal variability.