Decreasing Cropping Intensity Dominated the Negative Trend of Cropland Productivity in Southern China in 2000–2015

Zhongen Niu,Fang Liu,Huimin Yan

doi:10.3390/su122310070

Abstract

As the country with the highest food consumption in the world, China’s food security has been drawing global attention. The inter-annual variability of agricultural productivity and its predominant driving factors play important roles in food security and sustainable agricultural development. Here, we used gross primary productivity (GPP), which was simulated using the vegetation photosynthesis model (VPM), to quantify the spatial-temporal heterogeneity of cropland productivity from 2000 to 2015. The results showed that the cropland GPP significantly increased in northern China and markedly decreased in southern China. Socioeconomic and climatic factors jointly promoted a rise in GPP in the Northeast region, Inner Mongolia and Great Wall region, Huang-Huai-Hai region, and Loess Plateau region, with contribution rates of 93.6%, 67.9%, 73.8%, and 78.1%, respectively. The negative GPP trend in southern China was mainly attributed to the decreasing cropping intensity, with direct contributions of 54.1%, 53.9%, and 48.7% for the Yangtze River region, Southwest region, and South China region, respectively. Despite the decline in cropping intensity, the policies of Cang-liang-yu-di and Cang-liang-yu-ji can help in ensuring food security in China.

Highlights

Global agriculture is facing unprecedented challenges and risks: since the 1980s, yield growth rates have slowed [1,2] and even stagnated in many regions [3,4]
The negative gross primary productivity (GPP) trend in southern China was mainly attributed to the decreasing cropping intensity, while other factors had a relatively small impact
The increase in grain yield per unit area was the direct reason for the rise in cropland productivity in the north of China [52,53], which increased from 168.5 kg mu−1 in the 1980s to 316.5 kg mu−1 in 2007, primarily due to agriculture policy support and technological progress [20,53,54,55]

Summary

Introduction

Global agriculture is facing unprecedented challenges and risks: since the 1980s, yield growth rates have slowed [1,2] and even stagnated in many regions [3,4]. For China, the most populated country in the world, providing enough food to its 1.3 billion people has been an ongoing challenge, and food security has been one of the highest priorities [5,6]. The crop production of China has significantly improved in the past decades [7], and 12 years of consecutive increases were achieved between 2004 and 2015. Crop production is directly determined by the harvested area and yield [8]. Understanding the influencing factors of Chinese crop production is critical to future food policy. Few studies have quantified the relative contributions of socioeconomic factors and climate to the cropland productivity trend

Methods

Results

Discussion

Conclusion