Adaptability Evaluation Research Of Turfgrass On Reclaimed Water Irrigation And Soil Improvement Measures In Mining Area

In recent years, some problems encountered in the turf planting work at Shendong center green area, such as low germination rate, yellow and even death problems of turfgrass. In order to find out the causes of these phenomena, turf area with reclaimed water irrigation was selected as the object to study, by the way of sampling methods, detailed research and analysis of the water quality between typical wastewater treatment raw water and after the treatment water, comparing soil salinization effect between the turf area and cover plant area, to analyze comprehensively the risk on turf under reclaimed water irrigation. On this basis, from the perspectives of the design of turfgrass mixed seeding, water treatment, utilization, soil improvement and rejuvenation, through the evaluation of turfgrass adaptability on different mixed seeding scheme, different water quality and different soil substrates, this study aimed to analyze the feasibility of mixed seeding idea. At the same time, combining with the water quality index, soil index this research was to analyze effect of water treatment and the soil improvement.The main conclusions were as follows:1. From the point of mine water quality, the removal rate of sewage treatment plant that mine water and domestic sewage contain salinity is very low, there is almost no effect of desalination. According to the long-term monitoring of water quality in the typical sewage plant, Huojitu reclaimed water shows that total salt content is1300-2800mg/L, the conductivity value of1800～4000μs/cm, pH value of7.3-7.3. Heitangou reclaimed water shows that total salt content is800～1500mg/L, the conductivity value is1000～1600μs/cm, pH value of7.06～7.06. This proves that reclaimed water containing salt is still higher after sewage treatment plant.2. It was showed that the soil sample analysis for reclaimed water irrigation district were as below; the total salt and the ESP degree of ground cover soil was significantly higher than the control, so was the turf soil. It was more significant difference of the turf. The total salt content of ground cover soil and turf soil with reclaimed water irrigation were increased by26%and84.2%compared with the control; The ESP degree of ground cover soil and turf soil with reclaimed water irrigation were increased by64.5%and145.8%. More K++Na+and SO42-ions in the soil, which was consistent to the higher concentration of K+Na+and SO42-ions in reclaimed water. Reclaimed water irrigation was a potential risk of soil salinization. and it was the leading cause of turfgrass to yellow or death.So reclaimed water for turf irrigation risks should not be ignored.3. Greening in the mining area under reclaimed water irrigation should be the first choice plant adaptability and more salt tolerant plants, ensuring that the accumulation of salt in the reclaimed water for irrigation will not be harm to plants under stress, in order to extend the life of the plant. The key to the success is species selection weather suitable for the mining area greening in reclaimed water irrigation. The test of turfgrass salt tolerance results were as below:Nuglade, Blacksburg, Award of Kentucky Bluegrass.Tall fescue Barlexas, Perennial ryegrass Premier have strong salt resistance. For species, Perennial ryegrass> Tall fescue> Kentucky bluegrass.4. The thought of fast growing protection species+selection of mixed core for turfgrass, was suitable for the selection of grass species guiding high salt under reclaimed water irrigation establishment time. The protection of species should maintain certain sowing quantity, to ensure that the grass cover the ground rapidly. For the protection of species, Perennial ryegrass, Kentucky bluegrass mixed seeding can build high quality turf, as a public park, downtown area hospital, school, ornamental turf, and the ratio of sowing in Perennial ryegrass is20to40percentage; For the protection of species, Tall fescue, can be used as a mining area requiring only green, but not ornamental large space or slope planting material.The seeding ratio shall not be less than30percentage.5. Mine reclaimed water by reverse osmosis system deep desalting effect is more ideal, the water quality of reverse osmosis membrane treatment fully meet the standard of irrigation water. The average removal rate can reach more than90percentage, especially Ca2+and CO32-removal rate of almost100percentage. After the treatment, the salt content in an average of250mg/L, is much better than1000mg/L irrigation water standard. Mine reclaimed water mixed with reverse osmosis water effectively reduces the water salinity of mine, meanwhile, the mine reclaimed water is rich in plant growth nutrients.It can promote the seed germination and the growth of plants.By the way of mine reclaimed water mixed with reverse osmosis water by1:1, it can reduce the consumption of the reverse osmosis equipment and don’t violate meet the requirements of green water.To a certain extent, it played as a source control.6. In soil improvement measures, sludge improvment increases organic matter, total N and total P. That may lead to the increase of salt;sludge will for a short period of time increases the speed of N and P supply;stable carbon powder increases the speed of P content.Increasing gypsum can cause stable increase of the ion content of Ca2+. Mg2+in the soil,and effectively reduce the HCO3-ion content. pH and ESP degree,especially in conjunction with the clear water irrigation ESP degree a drop more.At the same time,promote the germination of the turfgrass of seed gypsum improvement,the growth of seedlings,and to speed up the emergence.It also improve the quality of the turf.In mine reclaimed water mixed1:1with the clean water for irrigation or direct clean water irrigated, turfgrass performance will be better.