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1

Effects of maternal vitamin D3 on quality and water distribution in pork of offspring pigs during frozen storage

100%
Guo L., Miao Z., Melnychuk S., Ma H.
Journal of Animal and Feed Sciences
|
2020
|
tom 29
|
nr 4
2

Changes of root-zone soil environment in flooded paddy field under controlled drainage conditions

100%
Xiao M., Miao Z., Li Y.
Polish Journal of Environmental Studies
|
2017
|
tom 26
|
nr 2
At present, farmland-controlled drainage is of great significance for water-logging control, water conservation, and emissions reduction. This paper focused on the water level of farmland to study the changes of root-zone soil environment in a flooded paddy field. Such technical indexes included the soil nutrient index of rapid available phosphorus (RAP) and rapid available nitrogen (RAN) in the 0-10 cm and 10-20 cm soil layers, the soil aeration condition index Eh value in the 15 cm soil layer, and soil temperature (ST), respectively, in the 5 cm and 20 cm soil layers. Additionally, this paper presented an analysis on the impact of water flooding in a paddy field on the soil’s microenvironment using the principal component factor method. Influence analysis results showed that different water level controls between CK (shallow and wetting irrigation) and F1 and F2 (controlled drainage) had a significant effect on the changes of RAN content in the 0-10cm layer, Eh value in the 15 cm layer, and ST value in the 5 cm layer, but different leakage intensities had no significant effect on the change of RAN, RAP, Eh, and ST. The results showed that water-flooding can improve the RAP content, reduce the RAN content of every soil layer, deteriorate the soil aeration status, and increase the soil temperature; additionally, the water-flooding had an adverse impact on the soil’s RAP, RAN, Eh, and ST at the tillering and milking stages. Water-flooding also had an adverse impact on the soil’s RAN and Eh at the jointing-booting and heading-flowering stages.
3

Effects of maternal vitamin D3 concentration during pregnancy on adipogenic genes expression and serum biochemical index in offspring piglets

100%
Guo L., Miao Z., Ma H., Melnychuk S.
Journal of Animal and Feed Sciences
|
2020
|
tom 29
|
nr 2
4

Nitrogen losses in paddy field drainage modified by different water level regulations

100%
Zheng S., Xiao M., Miao Z.
Polish Journal of Environmental Studies
|
2017
|
tom 26
|
nr 3
Nitrogen losses from farmland, through improper drainage and rainstorm runoff, cause non-point source pollution and limit sustainable agriculture development. We determined the effects of controlled drainage (CTD) and conventional drainage (CVD) on migration responses, the transformation of nitrogen, and NH₄⁺-N and NO₃⁻-N losses. The results showed that four days after a rainstorm, compared with day one, NH₄⁺-N and NO₃⁻-N decreased by ranges of 28.7-46.7% and 7.5-47.5% in CTD, which was significantly higher than CVD. CTD also significantly reduced NH₄⁺-N and NO₃⁻-N losses in field drainage compared with CVD. NH₄⁺-N was reduced by 66.72% and NO₃⁻-N reduction was 55.56%. NH₄⁺-N contributed most to nitrogen losses, while NO₃⁻-N contributed less. Following rainstorm events, varying the water level using CVD and CTD had significant effects on NH₄⁺-N and NO₃⁻-N concentrations. The DRAINMOD-II model was used to simulate NH₄⁺-N and NO₃⁻-N levels. It indicated that the observed and simulated values of NH₄⁺-N and NO₃⁻-N concentrations in both CVD and CTD were fitted better. Lastly, the innovation of this study was that it focused on nitrogen concentrations and load changes in paddy field drainage after rainstorms, firstly using the DRAINMOD-N II model to simulate NH₄⁺-N and NO₃⁻-N concentration changes under field scale. It further validated the pollution-reduction effect under water level control in the paddy field. Also, it improved the irrigation-drainage system of paddy rice and provided a scientific basis for optimizing irrigation-drainage project design in rice irrigation district.
5

Improving water productivity and reducing nutrient losses by controlled irrigation and drainage in paddy fields

64%
Gao S., Yu S., Wang M., Meng J., Tang S., Ding J., Li S., Miao Z.
Polish Journal of Environmental Studies
|
2018
|
tom 27
|
nr 3
Controlled irrigation and drainage (CID) has received considerable attention as a reliable management practice for improving water quality and water productivity in rice production. This study aimed to evaluate the effects of CID on water productivity, nitrogen, and phosphorus losses in paddy fields. Treatments include alternate wetting and drying (AWD; lower limit of irrigation to -200 mm and upper limit of ponding water depth after rainfall to 60 mm), CID-I (lower limit of irrigation to -200 mm and upper limit of ponding water depth after rainfall to 200 mm), and CID-II (lower limit of irrigation to -500 mm and upper limit of ponding water depth after rainfall to 200 mm). Results showed that CID reduced irrigation water without a significant impact on grain yields and increased the irrigation water productivity by 14.6-51.5% compared with AWD. However, the percolation of CID may be increased, especially in a wetting year. The application of CID-II by combining yield with irrigation water productivity could be suitable and beneficial to rice crops. The average total nitrogen (TN) and total phosphorus (TP) concentrations of CID presented similar values or were significantly increased relative to AWD, indicating that the significant decreases in nutrient loads under CID were primarily due to reductions in surface runoff rather than changes in concentration. Ammonium nitrogen (NH₄⁺-N) concentrations were clearly increased after fertilizer application in percolation water. Compared with AWD, the NH₄⁺-N, TN, and TP leaching losses of CID-I were increased. The nitrogen and phosphorus leaching losses of CID-II were significantly increased relative to AWD and CID-I because of high nutrient concentrations and severe preferential flow. Therefore, CID potentially increased nitrogen and phosphorus loading to groundwater when the lower limit irrigation was used. The results indicate that the suitable application of CID can save fresh water, reduce nutrient losses, and guarantee rice production.
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