Sustainable Agriculture: Theories, Methods, Practices and Policies

Due to the extensive degree of the consumption of resources and energy by industrial agriculture, there is a growing awareness of sustainable agriculture development that should not only increase yield to meet people’s demands for food security, but should also improve product quality and promote the multi-functionality of the agricultural ecosystem. Although research and practices of sustainable agriculture have achieved remarkable results over the past 40 years, the development of the social economy and the current challenges of the world agriculture necessitate further research to improve the future of agriculture. Therefore, summarizing our experiences and lessons, analyzing existing problems, and contemplating the future of development will lead to innovations in the realms of theories and practical methods, which will promote the practice and policy of sustainable agriculture.

This Special Issue includes 16 articles related to the theoretical methods, policies and systems of agricultural sustainability, as well as practical experience, focusing particularly on the former two, with the aim to contribute to the sustainable development of agriculture and food security.

1. Theories and Methods of Agricultural Sustainable Development

Food supply is one of the important purposes of sustainable agricultural development. Gilmar et al. [1] used an innovative in vitro technique to increase the cultivation of micro tubers, improve the yield and quality of seeds and crops, and ensure regional food supply.

With the objective to examine how to assess the sustainability of agricultural development, Wang et al. [2] constructed a comprehensive system of evaluation indexes for cropland–livestock systems from three aspects: arable land, animal husbandry, and the environment. They used a coupling coordination degree model to evaluate the coupling coordination relationship between cropland and livestock and its influencing factors in 31 provinces in China during 2000–2020. Their results clarified that reducing the decoupling of cultivated land and animal husbandry can reduce agricultural non-point source pollution, and that the combination of cultivated land and animal husbandry can promote agricultural sustainability. Yu et al. [3] proposed that an accurate measurement of agricultural total factor productivity (AGTFP) is crucial to measure the level of sustainable agricultural development, and that the inclusion of agricultural carbon sink in the AGTFP is more conducive to improving green total factor productivity, reducing carbon dioxide in agricultural production and improving the carbon sink capacity of farmland.

In addition, in terms of research methods, Wang et al. [4] used a novel hybrid model by integrating the Fuzzy set, Delphi, and the Grey theory, among others, to calculate the relationship between various factors in agricultural green supply chain management so as to grasp the relationship and key factors between each link, promote the reform of supply chain management, and promote agricultural sustainability. Based on the data gathered in 2016, from the China Family Panel Studies (CFPS) and from a variety of econometric models, Wang et al. [5] clarify that digital technology can promote land circulation (land leasing behavior), integrate fragmented land, reduce land abandonment, and achieve sustainable livelihoods for farmers.

2. Policies of Agricultural Sustainable Development

Abandonment is a major problem which is faced by the development of modern agriculture. Based on the survey data of 12 rural provinces in China, Xue et al. [6] analyzed the relationship between agricultural machinery harvesting services and abandonment, and proposed that agricultural machinery harvesting services can reduce cropland abandonment, which provides suggestions for policymakers to reduce cultivated land abandonment and ensure food security. Xue et al. [7] examined the relationship between financial literacy and farmland abandonment in Ghana, and found that the financial literacy of rural residents (especially low-income farm households and female farmers) is low, and pointed out that the lower the financial literacy, the more serious the phenomenon of cultivated land abandonment. Hence, the authors proposed that agricultural sustainability can be promoted by increasing the financial literacy training of rural households.

In addition, the development of circular agriculture is also an important system to ensure the sustainable development of agriculture. By measuring the efficiency and changes in the agricultural economy in 31 provinces and cities in China from 2017 to 2020, Guo et al. [8] pointed out that the implementation of a rural revitalization strategy can improve the efficiency of agricultural circular economy, promote rural economic development, social progress and ecological protection, and realize rural modernization. Finally, this Special Issue also assesses two livestock development policies.

By examining the impact of the implementation of the Converting Food Crops to Forage Crops Policy (CFFP) in the pilot counties of Hebei Province from 2010 to 2020 on the development of the herbivorous livestock industry, Zhang et al. [9] clarified that the CFFP can produce high-quality feed, improve the productivity of animal husbandry, and promote the sustainable development of agriculture and animal husbandry. Moreover, Li et al. [10] systematically reviewed the relevant theoretical and practical research of grassland eco-compensation in China, summarized the five characteristics and shortcomings of grassland ecological compensation, and point out that future work should focus on the response mechanism of herdsmen’s families and the improvement of compensation measures.

3. Practical Experience of Agricultural Sustainable Development

Different agricultural production technologies or models have been created around the world, effectively ensuring the sustainable development of regional agriculture. Marta M. Moreno et al. [11] analyzed the degradation of biodegradable (BD) plastic mulch with different compositions in different soil types, and proposed that different compositions of biodegradable (BD) plastic mulch should be selected for different soils. Taking Limpopo Province as an example, Tlou E. Mogale et al. [12] evaluated the productivity of different species of sorghum intercropping at different cowpea densities, and proposed that the combination of intercropping and no-tillage can improve crop yield and productivity, thereby promoting agricultural sustainability. Taking the rice–fish coculture system in Jingning, Qingtian, and Yongjia counties of Zhejiang Province as an example, Ye et al. [13] compared and evaluated the effects of various aquaculture and rice–fish coculture systems on the genetic diversity of aquatic animals, and proposed that the implementation of the rice–fish coculture system can improve the genetic diversity and food security of aquatic species, thereby promoting agricultural sustainability.

For business entities, it is necessary to pay attention to the capacity building of smallholder farmers on the one hand, and the synergy between small-scale and large-scale farming systems on the other. Bader Alhafi Alotaibi et al. [14] analyzed the views and opinions of 193 rice farmers in Pakistan with regard to the government’s public extension services and improving rice production efficiency, and concluded that Pakistan’s public extension services lack attention to small-scale rice farmers. The authors proposed that small-scale rice farmers are the main body of agricultural production and yet lack modern agricultural technology and knowledge; therefore, the government should pay more attention to and train small-scale farmers to ensure national food security and promote agricultural sustainability. From the perspective of system dynamics, Mary Scholes et al. [15] analyzed and evaluated the small-scale and large-scale farming systems of mangoes and nuts in the Vhembe district of Limpopo South Africa, and found that small-scale and large-scale farming systems can work together to achieve food security at all levels. They also proposed that large-scale and small-scale farming systems work collaboratively rather than independently.

Lastly, taking Pakistani farmers as an example, Rabia Mazhar et al. [16] investigated the effects of three contract-farming regimes—long-term, medium-term, and short-term contracts—on the land-improvement investment, productivity, and technical efficiency of contract farmers in Punjab, Pakistan. Additionally, the authors clearly proposed that the implementation of long-term contract-farming regime is important for sustainable land development and management.

In summary, this Special Issue provides a comprehensive overview of the theories, methods, policies, and practices of sustainable agricultural development, with the aim at providing new insights and contributions to sustainable agricultural development, modern agriculture, and rural revitalization. The papers in this Special Issue represent some of the latest and most promising research results in this field, and we are confident that this Special Issue will facilitate further research. Here, the invited editors would like to express their heartfelt gratitude to all the contributors, authors, and reviewers who have contributed to the high-level research presented in this Special Issue.