Study On Soil Nutrients And Farmland Nutrients Balance Under Fungus Waste Recycling

Farmland nutrient recycling and balance fundamentally determines the direction of development of soil fertility, and is directly related to environment. Fungus waste is a good organic fertilizer and soil conditioner, fungus waste recycling is the effective way for the development of agricultural recycling economy. In this study, the field experiment had set up6treatments:conventional fertilization(CK),50%fungus waste recycling(T1),100%fungus waste recycling(T2),150%fungus waste recycling(T3),200%fungus waste recycling(T4),250%fungus waste recycling(T5). Laboratory analysis such as continuous flow analyzer determination combined with the software statistical analysis were usd to study on the effect of fungus waste recycling for soil available N,P,K and total N,P,K; and apparent balance method were used to study the apparent balance of nitrogen, phosphorus, potassium under different fertilization modes, and discussed nitrogen environmental risks. The main results were showed that:(1)Compared with the conventional fertilization, the high fungus waste recycling levels(150%fungus waste recycling-250%fungus waste recycling)could effectively improve soil available nitrogen, available phosphorus, available potassium, and increased by23.14%～27.24%,15.47%～94.92%and9.55%～73.88%, respectively; and that of different fungus waste recycling levels had the general trend that increased with the increasing application rate of fungus waste. The effect of fungus waste recycling on soil total nutrients in rice season was significant than that of wheat season, and it can effective-ly improve soil total nitrogen, total phosphorus and total potassium in rice season, so the topsoil total nitrogen, total phosphorus and total potassium were increased by11.19%-71.10%,17.78%-33.33%and9.33%～12.17%.(2)Farmland nitrogen is mainly from fertilizer inputs which accounting for more than60%of the total nitrogen input, and fungus waste recycling reduced the nitrogen removed by crop harvest. Farmland nitrogen in different fertilization treatments were both surplus. The surplus of nitrogen in rice season were16.22～203.70kg/hm2, and in wheat season were72.75～293.55kg/hm2; moreover, the surplus of nitrogen under fungus waste recyclin-g were significantly increased with the increasing of nitrogen input. Application of fungus waste reduced the residual amount of nitrate nitrogen and ammonium nitrogen in soil, and nitrate nitrogen decreased8.04%-46.7%. Fungus waste recycling effectively reduced the nitrate leaching, and also significantly decreased the total amount of nitrogen leaching, the decreased was8.38%-26.94%, the effect of100%fungus waste recycling treatment was the most significant.(3)Farmland phosphorus were almost derived from fertilizers and fungus waste, the phosphorus output by grain were than straw, and fungus waste recycling significantly increased the phosphorus concentration of rice and wheat aboveground. The soil phosphorus of CK,T1,T2treatments in rice season and CK,T1treatments in wheat season had a deficient to1.24～17.35kg/hm2, and larger degree of phosphorus deficiency were in CK and T2among these treatments, while Tl tended to balance with a silght deficit. The phosphorus of the remain fungus waste recycling treatments were both surplus, the system surplus were52.37～211.78kg/hm2, and the surplus degree increased with the increasing amount of phosphorus input. The phosphorus surplus in wheat season was higher than that of rice season, and surplus phosphorus in non decomposition fungus waste are beneficial to soil phosphorus fertility betterment and help to expand soil available phosphorus pools.(4) Straw carried away large amounts of potassium from soil, especially the potassium concentration of rice straw were up to more than30g/kg, moreover farmland potassium depend on system external input, so the potassium of different fertilization treatments were in a deficit up to117.32～223.60kg/hm2in rice season, and the deficit rate were higher than60percent, therefore soil potassium pool were severely depleted. The conventional fertilizer had the highest bacteria potassium, whereas fungus waste recycling had reduce the deficiency of potassium. It should be appropriate to increase the potassium input to keep soil potassium balance. In wheat season, the potassium of conventional fertilizer was in a deficit of46.25kg/hm2, while that of fungus waste recycling treatments were both surplus, and the surplus capacity were54.11～539.05kg/hm2, and the extent of surplus increased with the increasing of potassium input. Most of the potassium that in excess input to farmland were remained in the non decomposition fungus waste, and it has a positive effect on improving soil potassium fertility especially on long time fertility betterment. (5)Integrated soil nutrients, farmland nutrient balance, environmental risks, rice and wheat productivity, the150%fungus waste recycling (14300kg/hm2) was the best fertilization modes while applying K2O200kg/hm2in rice season, and the250%fungus waste recycling (68058.33kg/hm2) was the best in wheat season, in order to improve soil nutrients, maintain rice and wheat higher yield, while keeping farmland nutrients balance and developing to appropriate surplus direction, and effectively reduce nitrogen leaching.