Exploring a Moderate Fallow Scale of Cultivated Land in China from the Perspective of Food Security

Abstract

Food security remains a primary concern because of the large population and scarce land resources in China, and it is a core task to determine the appropriate proportion and scale of fallowing for fallow systems. The aim of this study was to systematically estimate the grain production potential (GPP) of existing and unexcavated cultivated land due to land use change from 1990 to 2017 and calculate the theoretical fallowing scale by using a population carrying capacity model. The reserved GPP from cultivated land to be excavated was 7470 × 104 t in China, and the GPP stored by the change in grain yield per unit, multiple crop index (MCI) decline, and agricultural structure adjustment were 921 × 104 t, 4321 × 104 t, and 7760 × 104 t, respectively, and the lost GPP caused by construction land expansion was 5287 × 104 t. The population carrying capacity of cultivated land in China was estimated to be 1.469 to 1.515 billion in 2017 on the basis of the national average living standard. The proportion of the population that could be fed more was between 6.28% and 9.54% depending on the number of people included, which provided an opportunity to implement the fallowing system in China. Meanwhile the proportions of the theoretical fallow scale were 6.28% and 9.54%, and the fallow scale ranged from 850 × 104 hm2 to 1296 × 104 hm2 under the premise of fully tapping the potential of cultivated land. In addition, taking the decline in MCI as an example, the grain yield reduction was equivalent to the grain yield of 829 × 104 hm2 of newly reclaimed cultivated land over the past 30 years, which saved 621.48 billion yuan. The costs and benefits when formulating relevant policies of land utilization should be considered, and exploiting the productive capacity of cultivated land that exists is better than reclaiming new cultivated land.

Knowledge Mapping of Research on Land Use Change and Food Security: A Visual Analysis Using CiteSpace and VOSviewer

“…According to the prediction of the United Nations [ 11 ], the global population will exceed 9.8 billion in 2050, food demand will increase by more than 50%, and food problems will be extremely serious [ 12 ]. However, there are many factors affecting grain production, including institutional and policy innovation, scientific and technological progress, material and labor investment, climate change, but cultivated land resources in land resources are the most important factor in grain production [ 13 , 14 ]. Cultivated land resources are the most basic natural condition of agricultural production.…”

Impacts of global warming on the cropping systems of China under technical improvements from 1961 to 2016

“…Our previous study showed that the multiple cropping indices in China were among the highest levels in the world, which greatly contributed to China's food security (Yang et al., 2015). For example, the grain production capacity in China has massively improved, and the grain output has continuously increased for more than 15 yr since 2004 (Lu, Wang, Yang, He, & Su, 2019). Generally, China's MCS includes three types: single‐cropping system (SCS); double‐cropping system (DCS); and triple‐cropping system (TCS) (Yang et al., 2015).…”

The Status and Challenges of Sustainable Intensification of Rice-Potato Systems in Southern China

“…2020). Maintaining food self-sufficiency is the principle precept of China's current food security policy, which could be guaranteed if only considering the availability of cultivatable land resources (Fu et al 2001;Lu et al 2019). However, China is a densely populated country with a relatively small area of arable land.…”

“…Thirdly, soil resources are deteriorating. The long-term continuous cropping of rice and a general lack of awareness of how to maintain soil fertility (Lu et al 2019) in China's southern provinces has caused the deterioration the soil's physical and chemical properties. Evidence from Huang (2017) indicated that these regions' soils were severely depleted, with reduced organic matter and low soil fertility.…”