Investigation of differential fallow patterns and technical measures for cultivated land in China

Abstract: Cultivated land fallow pattern is an important part for the implementation of the arable land fallow system. Therefore, it is necessary to explore different fallow patterns for the fully utilization of farmlands in China. This paper aims to refine the differentiated fallow pattern of cultivated land using literature analysis and case studies, together with field data collected from the main pilot areas of cultivated land fallow in China. Results showed that: 1) the pattern design of cultivated land fallow depends on three factors, including system subject, system object and system environment, in the specific land fallow system. The guideline of pattern design can be based on the principle of available local conditions, food security, the trinity of social, economic and ecological benefits, and the main standard of "rest, maintain and utilization" for fallow land. In pattern design of differentiated cultivated land fallow, the main contents include the pattern definitions, pattern categories, applicable areas, case areas of pattern, and typical fallow technical measures. 2) Five fallow patterns of cultivated land in China mainly are: fallow pattern of water-saving and retention in the groundwater funnel area, fallow pattern of clean decontamination in the land pollution area, fallow pattern types of ecological restoration in the ecologically degraded area, productivity conservation of cultivated land in highly intensive cultivation area, and the pattern of "transfer + fallow" in the seriously abandoned area of cultivated land. 3) Technical measures of fallow patterns are related to fallow time, fallow cultivation and fertilization, fallow tillage, fallow experiment and demonstration fields. The fallow time of pattern design can be divided long-term, short-term and seasonal fallow. The fallow fertilization of patterns consists of no-till net green manure, less tillage with green manure and bean rotation, no-tillage green manure mixed with grass, no tillage manure returned to the field, straw returning, and organic fertilizer (fertilized farmyard manure), and mixing with the above various ways. The fallow tillage mainly includes crushing and returning green manure to the field, fallow shallowing, deep turning and drying, and rotary tillage, and other related technical systems. The fallow patterns of experiment and demonstration fields include a variety of screening test, fallow time test, determination test of soil index, and comparison test between fallow and uncultivated farmland. 4) The typical fallow experimental demonstration fields in Huanxian county, Gansu Province, can be expected to popularize in different fallow areas of China.