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Decades of intensive irrigation of farmlands in the oasis irrigated areas of Xinjiang, Northwest China has caused secondary salinization of vast areas of land since the mid-1980s. Based on the systematic analysis of the monitoring data of hydrology, soil, irrigation and salinity at two different scales in the case of Weigan River Plain Oasis in Xinjiang Province, algorithms derived from hydrosalinity balance principle were developed to estimate the salt mobilization and characteristics; salt and water mobilization and distribution were closely examined both in catchment scale and in field scale. The critical ratio of drainage to irrigation of Weigan River Plain Oasis was estimated to be 9.19%. Furthermore, analysis of the relationship between the two different scaling issues was illustrated. Finally, corresponding countermeasures for secondary soil salinization were proposed according to the different developmental stages and salinization status of water and soil resources.The findings of this paper is helpful in controlling the local hydrology, in limiting or diminishing salinization trends, as well as in providing academic and instructive meaning for the sustainable development of agriculture in oasis irrigation areas. [ABSTRACT FROM AUTHOR]

Objective: To investigate the distribution and related factors of intraocular pressure (IOP) in the screened population aged over 50 years in Wenzhou. Methods: This study included 31 170 community residents aged 50 years or older in Wenzhou undergoing screening from March 2014 to January 2016. Participants underwent a complete ocular examination, including visual acuity, eye-ground photography, slit lamp and standardized measurement of IOP by non-contact tonometry. Subjects who had undergone ocular operation or laser peripheral iridectomy, had glaucoma, corneal or other ocular diseases that could possibly affect the IOP, had an IOP lower than 6 mmHg(1 mmHg=0.133 kPa) and visual acuity less than 0.3, or had monocular IOP values were excluded. The relationship between IOP and various parameters were analyzed. Results: A total of 20 875 subjects (6 902 males and 13 973 females) were enrolled in the current analysis, including 18 677 healthy persons and 2 125 glaucoma suspects, with an average age of (67.3±8.7) years old. The mean IOP (mean±standard deviation) of the healthy population was (13.5±3.0) mmHg (13.4±3.2) mmHg in right eyes and (13.6±3.3) mmHg in left eyes; 2.04% of the left eyes, 1.51% of the right eyes and 2.92% of either eyes of healthy population had an IOP >21 mmHg. The mean IOP in glaucoma suspects was significantly higher than that in the healthy population ( P< 0.001); 6.78% of the left eyes, 6.16% of the right eyes and 9.65% of either eyes of glaucoma suspects had an IOP >21 mmHg. Men had lower IOPs than women [healthy population: (12.9±3.2) mmHg versus (13.7±3.2) mmHg; P< 0.05]. The linear function of IOP ( Y ) with age ( X (1)) and the vertical cup disc ratio ( X(2) ) was ^ Y =15.962-0.043 X (1)+0.837 X(2) ( P< 0.05) in the healthy population. Conclusion: The IOP among healthy persons aged over 50 years living in downtown Wenzhou was decreased with age but increased with the vertical cup disc ratio. The IOP in females was higher than that in males. About 3% of the healthy population had an IOP greater than 21 mmHg. (Chin J Ophthalmol, 2018, 54: 586-592) .