【Focus】The Application Effects of Yishizhuang in Reducing the Use of Chemical Fertilizers for Vegetables in Changyang County

Abstract: An experiment and demonstration were carried out on applying "Yishizhuang" organic-inorganic vegetable fertilizer to radishes, which are high-mountain vegetables. The results show that the average yield of radishes per 667 square meters increases by 588 kilograms. Using organic-inorganic fertilizer can reduce the pure nutrient content by 20% compared with applying inorganic fertilizer alone, and the yield increases by more than 9%. It plays a role in making full use of soil nutrients and improving the physical and chemical properties of the soil.

Keywords: High-mountain vegetables; Organic-inorganic fertilizers; Reduction of chemical fertilizer use

Over the past more than 30 years, high-mountain vegetables have been planted year after year. The transition from using ammonium carbonate and phosphate fertilizers to the full application of special fertilizers has played an important role in increasing vegetable yields and farmers' incomes. However, with the continuous application of chemical fertilizers, soil acidification has gradually become more severe. Nitrogen elements volatilize and are lost, while phosphorus and potassium elements accumulate in the soil. Farmers' investments keep increasing, but due to the law of diminishing returns, their incomes are getting lower and lower. Some farmers apply chemical fertilizers alone in an amount of 150-250 kilograms, which undoubtedly leads to a decline in the quality of cultivated land and causes non-point source pollution. Scientific fertilization, the combined use of organic and inorganic fertilizers, and the reduction of chemical fertilizers are now extremely urgent.

1. Materials and Methods

   1.1 Overview of the Experimental and Demonstration Sites
   The experiments and demonstrations were carried out in the Huoshaoping vegetable base in Changyang County, Hubei Province, which is known as the first county of high-mountain vegetables in the country. The experimental fields have mountain brown soil. The soil has a pH value of 5.1, with alkali-hydrolyzable nitrogen content of 157 mg/kg, available phosphorus content of 35.4 mg/kg, available potassium content of 218 mg/kg, and organic matter content of 29.1 g/kg. Chinese cabbage, radishes, and cabbages have been planted here for a long time. In 2016, the demonstration area for radishes was 67 hectares. Under the same conditions of planting varieties, cultivation, and management measures, a comparison was made between the application of organic-inorganic fertilizers and pure inorganic fertilizers.

1. Analysis of the Actual Yield Results

   2.1 Impact on the Yield of Radishes
   Supplementing soil organic matter can promote the decomposition of accumulated nutrients in the soil for crops to absorb, and improve the utilization efficiency of inorganic fertilizers. Compared with the use of inorganic fertilizers alone, the yield of radishes increases by an average of 588 kilograms per 667 square meters.

2.2 Comparison of Chemical Fertilizer Reduction When applying organic-inorganic fertilizers to radishes, 24 kg of NPK is used per 667 square meters. In farmers' customary fertilization, 30 kg of NPK is used per 667 square meters. On average, the amount of NPK used per 667 square meters is reduced by 6 kg, and the input of pure nutrients is reduced by 20%. The investment in fertilizers is saved by 10.00 yuan per 667 square meters, and the cost savings and increased income per 667 square meters reach 480.00 yuan on average. 

 2.3 Impact of Organic-Inorganic Fertilizers on Vegetable Growth Vegetables are cash crops with a high demand for fertilizers. The combined use of organic and inorganic fertilizers not only overcomes the difficulty of ensuring the nutrient requirements for vegetable growth when only organic fertilizers are applied, but also provides material support for the combination of soil utilization and nutrient replenishment. Long-term application of only inorganic fertilizers will lead to soil compaction, intensified soil acidification, accumulation of phosphorus and potassium, and hindered biological activities. Supplementing soil organic matter can effectively improve the physical and chemical properties of the soil and provide a carbon source for biological reproduction and activities. Due to the vigorous biological activities, the phosphorus and potassium enriched in the soil are decomposed for crops to absorb, realizing the reuse of resources and achieving the effect of increasing yield while reducing the use of chemical fertilizers, thus enabling farmers to save costs and increase efficiency. 

 3. Discussion and Conclusions 

 3.1 Organic Fertilizers Cannot Completely Replace Chemical Fertilizers With the rapid development of agriculture, people have higher material demands. Cultivated land is non-renewable. Relying solely on organic fertilizers to produce agricultural products cannot meet people's growing demand for agricultural products. Relying on chemical fertilizers, on the other hand, has an impact on the quality of cultivated land. Only by using them in combination can a win-win situation be achieved. Therefore, organic fertilizers cannot completely replace chemical fertilizers. For a considerable period of time, the only way forward is to combine organic and inorganic fertilizers. 

 3.2 The Combined Use of Organic and Inorganic Fertilizers is an Important Measure for Chemical Fertilizer Reduction Chemical fertilizers are high-energy-consuming products. Reducing their use can reduce energy consumption and protect limited resources. Developing organic fertilizers using waste resources is in line with China's national conditions. Practice has proven that the use of bio-organic fertilizers and the combination of organic and inorganic fertilizers can effectively reduce the amount of chemical fertilizers used. 

 3.3 Cash Crop Producing Areas Should Be Alert to the Consequences of Excessive Fertilization Currently, farmers blindly pursue high yields, ignoring the bearing capacity of cultivated land. Blind and excessive fertilization are common phenomena. The imbalance of macro, medium, and trace elements leads to frequent occurrence of physiological diseases, resulting in a vicious cycle where fertilization does not increase yield and spraying pesticides is ineffective. 

 3.4 The Concept of Fertilization Needs to Be Innovated The long history has led farmers to accept traditional models such as the use of farmyard manure, the combination of ammonium carbonate and phosphate fertilizers, and the formula of compound fertilizers. Now, it is necessary to adopt a full-element model that combines organic and inorganic fertilizers. Hubei "Yishizhuang" Agricultural Technology Co., Ltd. has put forward a new concept of fertilization based on years of practical results: lightweight and simplified (formulating according to the needs of crops for macro, medium, and trace elements, allowing farmers to apply fertilizers at one time, saving labor, time, and worry); medium concentration (high-concentration compound fertilizers usually have ratios like 3 times 15, 16, or 17, which do not meet the growth requirements of crops and cause serious nutrient waste. Special fertilizers formulated according to the growth needs of crops have significantly better effects than fertilizers with the same nutrient content); full elements (different crops have different nutrient requirements, and sensitive medium and trace elements are added to fertilizers according to the crops); "zero investment" (it does not mean not applying fertilizers, but rather increasing the investment in fertilizers to obtain higher benefits, investing more to earn more money and improving the output-to-input ratio). Practice has proven that the innovative concept of scientific fertilization is scientific and practical and will contribute to the progress of agricultural production. 

 3.5 Bio-Organic Fertilizers and Organic-Inorganic Fertilizers Have Broad Prospects To ensure food security, the state has put forward the strategy of reducing chemical fertilizers and increasing organic matter content, aiming to maintain the bottom line of cultivated land quality. Hubei "Yishizhuang" Agricultural Technology Co., Ltd. has hired well-known domestic professors and experts for guidance and developed full-element bio-organic fertilizers and organic-inorganic fertilizers, as well as a series of special fertilizers for the national citrus system, rapeseed system, tea system, vegetable system, etc. These fertilizers have been promoted in 7 provinces and cities across the country and are deeply welcomed by farmers. The combination of organic and inorganic fertilizers will be the development strategy in the next few years. Whether it is grain, oil, vegetables, fruits, or cash crops, the combination of organic and inorganic fertilizers should be implemented. Farmers' harvests will gain their trust in the enterprise, and using the laws of nature will promote the development and progress of agriculture.