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【Objective】 Bioavailable phosphorus and oxygen are key factors affecting root activity and crop yield. The objective of this paper is to elucidate how phosphorus fertilization and irrigation-water aeration combined to affect root physiological traits, zinc absorption and allocation in rice and grain yield at maturation stage. 【Method】 The experiment was conducted in pots using the variety of Liangyou 608 as the model plant. It consisted of two irrigation treatments: aerating irrigation (OI) and conventional irrigation (NI), and four phosphorus fertilizations: 0.00 (P1), 1.35(P2), 2.7 (P3), 4.05g /pot (P4). In each treatment, we measured root activity, root acid phosphatase activity at different growth stages, as well as zinc allocation and grain yield at maturation stage. 【Result】 ① Phosphorus fertilization reduced zinc content in the iron-manganese films by 33.38% to 60.41%, while oxygenating irrigation water increased the transfer coefficient of zinc from root to straw by 24.98% to 113.15%. Aeration and phosphorus fertilization combined to increase zinc content in straw, but reduce the transfer coefficient of zinc from straw to grains. ② The combination OI+P1 gave the highest grain yield, 1000-grain weight, effective panicle numbers and zinc distribution, which were 140.45 g/pot, 27.57 g, 29.00 per plant and 29.52%, respectively. ③ Phosphorus application increased root activity at tillering stage, reduced root acid phosphatase activity at filling stage, inhibited the absorption and accumulation of zinc in roots at maturation stage, promoted transfer of zinc from straw to grain, and increased grain yield and seed setting rate. Aeration and phosphorus fertilization reduced the activity of root acid phosphatase at tillering stage, increased the activity of root acid phosphatase at filling stage, and increased the zinc content in rice straw and grain, but reduced the number of effective panicles, seed setting rate and the transferability of zinc from straw to grain. 【Conclusion】 Phosphorus fertilization combined with irrigation-water aeration affects the formation of rice yield due to their influence on the physiological characteristics of the rice roots at tillering and filling stages, as well as zinc translocation to grains. Irrigation-water oxygenation promoted the absorption and distribution of zinc in rice straw.

To prevent coal mine water disasters, the main objective of this study is to predict the water enrichment of the main aquifer in a coal mine of China that has been threatened by water inrush. The prediction is carried out using a geographic information system (GIS) and a coupled analytic hierarchy process (AHP) and entropy model. The flushing fluid consumption, burnt rock distribution, sand–shale ratio, and lithology structure index were determined as the main factors controlling the water enrichment of the aquifer. A thematic map of these main factors was constructed using the spatial data analysis functions of GIS and the data from a total of 146 drilling columns and field investigation. The weights of these controlling factors were calculated using the coupled model. A prediction map of the water enrichment of the aquifer was then developed by overlaying the thematic map with the weights of each controlling factor. The degree of water enrichment was finally divided into four levels for easy interpretation, where Level I denotes the highest water enrichment and poses the greatest threat of water disaster.

In view of traditional single upper corner gas control technology cannot effectively solve problem of severe over-limit of gas at upper corner of high-intensity fully mechanized caving face, taking Wangjialing Coal Mine as engineering background, the paper puts forward a scheme of combined gas drainage by use of upper corner inserted(buried) pipe and high-level directional boreholes. To INSERT INTO (bury) pipe at upper corner, gas drainage pipe is laid in return air lane of working face. The pipe extends along direction of return air lane to upper corner and forms a stable negative pressure zone at the pipe mouth to extract gas at the upper corner. Artificial air flow is formed through suction to disturb cyclotron vortex at the upper corner and reduce gas concentration. At the same time, in drilling site of the return air lane of the working face, the high-level directional borehole is constructed to drill in direction of cutting holes of working face, and the borehole track is extended in fissure zone of goaf through directional drilling technology to extract high concentration gas in the goaf. The application results show that after the combined gas drainage of upper corner inserted(buried) pipe and high-level directional borehole, gas drainage pure volume is stable at 3.40-6.20 m3/min, with an average value of 4.91 m3/min; gas volume fraction in upper corner of the working face decreases in steps, and finally stabilizes at 0.30%-0.52%, with an average value of 0.42%. The gas control effect in upper corner is significant.

Based on the problem of large gas emission and serious gas accumulation in upper corner of the intensive fully mechanized caving face, taking the fully mechanized caving face of Wangjialing Coal Mine in Hedong Mine as the research object, the main gas emission sources of the extremely intensive mining face with low permeability and low gas content were studied. The methods of gas extraction by inserting (burying) pipe in upper corner and directional drilling in upper corner were adopted and carried out. The application of engineering practice and comparative test of effect are carried out. The results show that the maximum extraction purity is 2.8 m³/min, the maximum gas concentration is 0.8% in upper corner, 3.11 m³/min in the high directional borehole and 0.71% in upper corner. After combined extraction, the total extraction purity is 1.33~7.93 m³/min and the fluctuation range of gas concentration in upper corner is reduced to 0.31~0.61% safe point. The effect of gas prevention and control in working face is remarkable.