1. Introduction
The world is facing tremendous pressures related to food shortages and the achievement of the Sustainable Development Goal of Zero Hunger [
1]. By 2020, 690 million people worldwide were suffering from hunger, and that number is expected to exceed 840 million by 2030 [
2,
3]. As the population grows unceasingly, at least 13 billion tons of extra food a year will feed an estimated 2 billion people by 2050 [
4,
5]. This massive demand for food is affecting cultivated land productivity and sustainable food production. Cultivated land quality (CLQ), an essential attribute of cultivated land associated with food production, is expected to have crucial impacts on regional food security [
6,
7,
8,
9]. Thus, to better protect food security, the improvement of CLQ has been increasingly advocated.
Different actionable measures have been developed to improve CLQ in hungry regions and food-starved cities, including the establishment of a sustainable food production system [
10], the creation of a disaster-resistant cultivating method [
11], adaptation to climate change of a cultivated land ecosystem [
12], and the fertilization of soil [
13,
14]. The achievement of a high and stable yield in cultivated land successfully verifies the critical impacts of these activities on CLQ [
15,
16]. However, scholars are also making an effort to measure CLQ quantitatively. Constructing a comprehensive index system is a general approach that has been used to measure CLQ in previous studies and some international programs, such as FAO’s Land Evaluation Program [
17,
18,
19], Land Evaluation and Site Assessment (LESA) [
20,
21,
22], Land Quality Indicators (LQIs) [
23,
24], and Sustainable Land Use Management Program [
25,
26]. Furthermore, a theoretical framework for CLQ based on connotation or procedure has been introduced to clarify the index systems of CLQ from single or multiple dimensions [
27,
28,
29,
30,
31]. Methodologically, an analytic hierarchy process (AHP) [
32], principal component analysis (PCA) [
33], and factor analysis (FA) [
34] have been used to extract index rules [
35,
36]. Moreover, these methods have effectively evaluated CLQ in China and other countries where the cultivated land per capita was low [
35,
37].
However, challenges remain for developing countries when evaluating CLQ using these various index systems [
38]. China, for example, has evaluated CLQ from different dimensions according to the government’s varied management goals [
39]. Specifically, the land management department, agricultural ministry, and environmental authority have evaluated CLQ from the perspectives of land use, soil fertility, and land pollution, respectively [
40,
41,
42]. These evaluation systems focused on identifying farmland productivity may be suitable for evaluating the relationship between yield and CLQ, but they have so far failed to take the nature, economy, and ecology conditions of cultivated land into consideration.
CLQ is usually a comprehensive concept that is considered a physical geo-socio-economic complex composed of climate, soil, parent material, topography, hydrology, vegetation, and human activities [
3]. Many studies continue to argue that solely focusing on productivity in the absence of other factors (e.g., natural calamities) may not provide sustainable support for agriculture [
43]. However, engineering measures can guarantee a high and stable yield from high-standard cultivated land regardless of drought and flood from a modernized agricultural standpoint [
44,
45]. Notably, to transform medium- and low-yield cultivated land into high-standard cultivated land, China has implemented a master plan for said high-standard cultivated land, and has promoted the protection of the quantity, quality, and ecology of cultivated land [
46,
47,
48]. As of 2021, more than 53.33 million hectares of concentrated contiguous high-standard cultivated land with a sound ecology have been developed [
49]. These achievements show that multiple departments’ cooperation is conducive to evaluating CLQ in a comprehensive manner. It is vital to evaluate CLQ from multidimensional perspectives to provide systematic knowledge for improving the CLQ of China.
China’s grain production has exceeded 0.65 trillion kilograms since 2017. The top province for grain output in China is Heilongjiang province, which produced 11.3% of Chinese grain in 2020. Heilongjiang province possesses 12.5% of China’s high-standard cultivated land; however, it also contains two agricultural concepts, namely modern agricultural area (MA) and traditional agricultural area (TA) [
50]. MA implements a management system with business enterprises in state-owned farms so that cultivated land ownership is managed and controlled by the state. TA, however, is characterized by a household responsibility system. Cultivated land ownership is collectively owned by villagers in this area. Cultivated land was used earlier in TA than in MA. However, agricultural management, landscape, and cultivated land-use behaviors vary between the two areas [
51]. Generally, it is difficult for researchers to compare CLQ in relation to MA and TA due to different population qualities, environmental conditions, geographical locations, and social and economic factors. Fujin city, in Heilongjiang province in Northeast China, provides an ideal case to discern these differences and similarities. There are apparent differences in CLQ under different tillage conditions and agricultural management strategies in almost the same geographical environment. Comparing the differences between them can provide a direct reference for improving CLQ in the transformation to modernized agricultural practices.
Considering Fujin city as the study area, the objectives of this study were to construct a systematic CLQ evaluation system from a multidimensional perspective and compare the differences in CLQ between MA and TA so as to provide guidance and new information for the improvement of CLQ. This work thus aims to answer two questions: (1) What are the multidimensional characteristics of CLQ at the plot scale? (2) What are the CLQs in two adjacent areas (MA and TA) in the same exact physical geographical location, and how much of a difference does location make? We first introduce the theoretical framework and present the multidimensional indicator system for CLQ. Then, we present an evaluation method of CLQ that we will use to compare the two adjacent areas. We introduce the study area and describe the whole process of data processing. We then compare the difference by reporting the results of total values and individual values of CLQ. Following this, we discuss the reason for the proposed difference and provide suggestions for how to improve CLQ in these two areas. Finally, we present conclusions and expected directions for future studies.
6. Discussion
This paper built a hierarchical evaluation system for understanding CLQ from a multidimensional perspective. The framework was applied to typical MA and TA in Fujin City, Heilongjiang Province. The results were similar to the actual situation in these two areas, proving the framework’s effectiveness. According to the evaluation results, we found that the comprehensive CLQ in MA is better than that in TA, but cultivated land individual quality results are not the same as comprehensive quality (see
Table 3). The results are consistent with previous studies. For example, Li’s study [
51] found that MA has better comprehensive benefits than TA, while not all sub-benefits are the same. Modern management could improve CLQ, which is evident in the same natural environment between MA and TA, at least in theory. Perfect engineering construction, reasonable cultivated land distribution, and an adjustable ecosystem are also expected to benefit grain yield improvements (see
Table 5). Consistently, project quality, landscape quality, and ecological quality were better in MA than in TA (see
Table 4). In summary, a comprehensive CLQ evaluation using the provided framework produced reliable results in Fujin city.
Moreover, multidimensional indicators implicate the interactive relationship between the natural environment and human activities (see
Figure 1). This interaction will continue to take place after cultivated land is strongly disturbed. In addition, cultivated land quality also varies by the intensity of cultivated land use. Zhen and Yadav’s studies [
54,
58] have shown that excessive and intensive use will deplete soil fertility, and our study provides new evidence for this fact. Specifically, we found that the fertility quality in MA was worse than that in TA (see
Figure 4B1,B2); meanwhile, ecology quality in MA was better than in TA (see
Figure 4E1,E2). This point is associated with higher intensity and single cropping patterns in MA, which may affect biological diversity and lead to the homogenization of ecological quality. We found that MA has advantages in project and landscape quality, which might be associated with the modernized land consolidation in MA (see
Figure 4C1,C2,D1,D2). Many land consolidation projects conducted in MA make cultivated land more regular, road networks run smoothly, and irrigation and drainage facilities more abundant. These might also be the main reasons why the grade of CLQ in MA tends to be the same from a landscape perspective.
It is widely accepted that an agrarian property system is considered to have significant impacts on cultivated land use. The cultivated land in MA is contracted to paid business workers for no more than five years, while cultivated land in TA is given to villagers without compensation for a 30-year contract period. Previous studies have shown that the different agrarian property systems between MA and TA could create different cultivated land benefits. Our study further illustrated that the agrarian property systems could also affect CLQ. With gradual advancements in agricultural modernization, and the continuous expansion of the connotation of the concept of cultivated land quality, relevant scholars have gradually realized that the title is also an essential part of cultivated land quality and an essential factor affecting it [
68,
69]. Qian et al. [
70] found that the instability of land rights will affect farmers’ farmland quality protection and reduce the behavior of soil organic fertilizer and straw for improving the quality of cultivated land. The results showed that the CLQ of MA was lower than TA. High engineering quality and landscape quality of cultivated land in MA is a fundamental reason for its higher comprehensive quality than TA. The relative stability of land rights in TA makes its fertility quality higher. Therefore, based on the property rights of MA and TA, appropriate cultivated land use and protection measures play a positive role in improving CLQ and the sustainable use of cultivated land resources.
For the reasons above, the CLQ of MA and TA shows a significant difference. We realized that different and common problems need to be addressed between the MA and TA to improve CLQ. Thus, this paper advocates four strategies to improve CLQ: (1) We should strengthen land consolidation and support facility construction to solve cultivated land fragmentation and enhance disaster prevention and mitigation of cultivated land, especially in towns and villages of TA. (2) We must strengthen soil fertility maintenance in agricultural production and reduce human interference with soil to ensure the sustainable use of cultivated land. (3) We should develop the ecological environment of cultivated land, especially in TA, to improve CLQ. (4) We must carry out a multidimensional cultivated land quality survey to gather more detailed information on CLQ.
This paper reveals the essential characteristics of cultivated land quality in typical MA and TA in Northeast China, and shows a positive significance for the rational use of cultivated land resources. Cultivated land from four dimensions was analyzed in this research, but the evaluation index of cultivated land quality lacked biological indicators. Therefore, future evaluations of cultivated land quality should be combined with the essential characteristics of a given region to select the relevant biological indicators to more objectively reflect the quality of said cultivated land. Meanwhile, it should also be the focus of future research to objectively reveal the obstacle factors related to cultivated land quality and then formulate a regulation mode for MA and TA according to local conditions.