## 1 Introduction  
Competition between large-scale farms and small-scale peasant households and between traditional farmers and new agricultural operation entities as well as the sustainable development of these farms remain common challenges facing the world today [1, 2, 3]. The usual result is that larger farms are getting larger while smaller operations are decreasing in number, thereby achieving agricultural economies of scale. Economies of scale refer to a kind of phenomenon that increases output, reduces the long-term average cost, and increases economic benefit by expanding the scale of production under the certain technical conditions. It reflects the relationship between the concentration of factors of production and the economic benefit. Agricultural scale operation contains elements of agricultural production, agricultural management entities, agricultural management links, and agri-business; its category is greater than that of land scale operation. Land as a basic part of agricultural production, land moderate scale management is a kind of important embodiment of moderate scale management of agriculture. Agricultural land moderate scale management refers to agricultural land management scale that achieved the best land scale benefit [4]. For more than half a century, scholars have conducted a lot of research on agricultural scale operations and made major progress, which is detailed as follows. 1. On a spatial scale, agricultural scale management involves both the macro level (national level, cross-regional level) and micro level (plot level, peasant household level) [5; 6; 7; 8; 9; 10; 11; 12].The research focused on the cost and profit analysis of farmland fragmentation and consolidation [13; 14; 15], as well as the relationship between farm size and land productivity [16; 17]. [PERSON] et al. [18] considered the potential endogeneity of land fragmentation and differences in crop selection. Relevant research results have also emerged from the micro perspective of production and management individuals, the meso perspective of industrial organization development, and the macro perspective of industrial integration [19]. Due to the different spatial scales of the research, the conclusions are varied and sometimes even contradictory. At the urban scale, emphasis is placed on the multifunctional and sustainable development of urban agriculture rather than its scale operation [20]. Generally, a high percentage of small farms, farms that are tenanted, part-time farms, and farms that are fragmented is a typical structural characteristic of agriculture in the peri-urban regions [21]. Therefore, in the suburbs of big cities, is developing agriculture moderate scale operation feasible? 2. Research on the influencing mechanism of agricultural scale management is gradually deepening. The comparative study on economies of scale and diseconomies of scale of farmland is extended to investigate the \"degree\" of the moderate-scale operation of farmland. For agricultural production units, the bigger the scale is not the better, moderate scale management is the most important. In Asia, for example, it is the average agricultural workforce management 3 ha of arable land in the early 1980s [21]. However, actual operation processes, due to differences in business objectives, usually will produce different agricultural moderate scales. At the same time, agricultural moderate scales have features such as regional difference, time variability, and diversity of form [22; 23; 24]. Therefore, how to determine the agricultural moderate scale is still a complex problem. It is generally believed that land fragmentation will increase farmers' production costs and affect agricultural returns to scale [25; 26; 27], while farm size and land fragmentation will restrict agricultural mechanization [28].