Remote Sensing Monitoring and Spatial Pattern Analysis of Non-Grain Production of Cultivated Land in Anhui Province, China

Abstract

In recent years, non-grain production of cultivated land (NGPCL) has become increasingly prominent in China, seriously affecting food production and threatening the country’s food security. However, there is a lack of large-scale and high-precision methods for remote sensing identification of NGPCL. From the perspective of effective management of cultivated land resources, the characteristics of the spatial patterns of NGPCL, both on a large scale and at a patch scale, need to be further studied. For solving this problem, this paper uses the Google Earth engine (GEE) cloud computing platform and multi-source remote sensing data with a machine learning algorithm to determine the occurrence of NGPCL in Anhui province in 2019, and then uses nine selected landscape pattern indexes to analyze the spatial patterns of NGPCL from two aspects, specifically, economic development level and topography. The results show that: (1) terrain features, radar features, and texture features are beneficial to the extraction of NGPCL; (2) the degree of separation obtained by using an importance evaluation approach shows that spectral features have the highest importance, followed by index features with red edges, texture features, index features without red edges, radar features, and terrain features; and (3) the cultivated land in Anhui province in 2019 is mainly planted with food crops, and the phenomenon of NGPCL is more likely to occur in areas with high economic development levels and flat terrain. Aided by the GEE cloud platform, multi-source remote sensing data, and machine learning algorithm, the remote sensing monitoring approach utilized in this study could accurately, quickly, and efficiently determine NGPCL on a regional scale.

Progress and Prospects of Non-Grain Production of Cultivated Land in China

“…Depending on the type of output, NGPCL is used for growing non-grain products, NGPCL is used for growing non-edible agricultural products, and NGPCL is used for growing non-agricultural products [22,23]. Moreover, its classification is based on the degree of damage to the plow layer with weak damage involving the planting of herbaceous plants, fruit trees, tea trees, and other low shrubs; gradual damage involving economic forests, fruits, fast-growing forests, and horticultural transplanting with soils; and severe damage involving pond digging for aquaculture and hardened covering [24][25][26][27][28][29][30][31][32][33][34][35]. NGPCL is a new issue that has emerged in the context of China's unique circumstances, reflecting the complexity of the country's agricultural restructuring and economic development.…”

“…To accurately assess the scale of NGPCL, scholars have employed the NGPCL rate, which is based on household survey data [26,27], statistical yearbook data, or remote sensing interpretation data [28][29][30][31]. This rate measures the proportion of non-grain sown area to the total area of cultivated land or the proportion of non-grain crops to the total sown area of crops [32,33].…”