Path Exploration and Countermeasure Innovation for Developing Circular Agriculture in Southeast China

This paper firstly elaborated current situation of agricultural resources and ecological environment protection of China, and pointed out that circular agriculture is an inevitable choice for sustainable development of agriculture and effective approach for low-carbon economic development. Then, it analyzed mode and benefit of typical circular agriculture, such as ecological orchard in southeast hills, sightseeing ecological agricultural garden, and crop straw use. Finally, it came up with countermeasures for further developing circular agriculture, including integrating building system and establishing suitable mode, formulating production standard and ensuring food safety, strengthening technological innovation, and supporting sustainable development

Seasonal Change in Microbial Diversity and Its Relationship with Soil Chemical Properties in an Orchard.

This study aimed to determine the microbial diversity at different soil depths (0-5 and 5-20 cm) in a subtropical orchard during different seasons (i.e., spring, summer and autumn) to advance knowledge of the roles of microbes in orchard ecosystem balance. In tracking experiments conducted in an orchard (established in 1996), the phospholipid fatty acid (PLFA) biomarker method was employed to determine the soil microbial system. The total PLFA concentration did not vary significantly between soil depths but changed between seasons. It peaked in the summer at 258.97 ± 23.48 μg g soil-1 from 0-5 cm and at 270.99 ± 58.94 μg g soil-1 from 5-20 cm. A total of 33 microbial fatty acid biomarkers were observed and identified in the sampled soil. The quantities of PLFAs for 29 microbial groups varied significantly between seasons, except for 15:0 iso 3OH, 15:1 iso G, 16:0 2OH, and 17:0 iso 3OH. The bacterial PLFAs and fungal and actinomycetic PLFAs in the orchard soil collected in summer were significantly more abundant than those collected in the spring or autumn (P < 0.01). The number of soil microorganism species (richness) and the Simpson and Shannon-Wiener indexes were all highest in summer. The total PLFAs, bacterial PLFAs, fungal PLFAs, actinomycetic PLFAs, richness, and Simpson and Shannon-Wiener indexes were all significantly negatively correlated with soil pH, total organic carbon (TOC), total nitrogen (TN) and the cation exchange capacity (CEC) (P < 0.05)

Research Advancements in Swine Wastewater Treatment and Resource-Based Safe Utilization Management Technology Model Construction

Swine wastewater contains large amounts of organic matter, nutrients, toxic metal elements, and antibiotics. If it is directly discharged or not properly treated, it poses a significant threat to the environment and human health. Currently, the management of swine wastewater has become a focus of social attention, and it adopts a dual-track parallel model of standard discharge supplemented by resource utilization. If treated properly, it can achieve the recycling of water resources and promote the effective recovery of resources. Based on the pollution characteristics of swine wastewater, this paper analyzes its impact on the environment, society, and the economy in detail and expounds on the research progress of swine wastewater treatment technology. From the perspective of resource utilization and recycling of anaerobic digestion liquid (biogas slurry) from swine wastewater and the carrying capacity of the soil environment and cumulative ecological environmental risks, this study explores new development trends and application prospects for swine wastewater treatment technology

Ecosystem services and ecological restoration in the Northern Shaanxi Loess Plateau, China, in relation to climate fluctuation and investments in natural capital

Accurately identifying the spatiotemporal variations and driving factors of ecosystem services (ES) in ecological restoration is important for ecosystem management and the sustainability of nature conservation strategies. As the Green for Grain project proceeds, food provision, water regulation and climate regulation services in the Northern Shaanxi Loess Plateau (NSLP) are changing and have caused broad attention. In this study, the dynamic pattern of the normalized differential vegetation index (NDVI) and the main drivers of grain production (GP), water yield (WY) and net primary production (NPP) in the NSLP from 2000-2013 are identified by incorporating multiple data and methods, in order to provide a better understanding of how and why ES change during ecological restoration. WY was simulated by hydrological modeling, and NPP was estimated with the Carnegie Ames Stanford Approach (CASA) model. The results show that vegetation restoration continued from 2000-2013, but fluctuated because of the comprehensive influence of climate and human activity. GP and NPP both exhibited significantly increasing trends, while changes in WY occurred in two stages: decline (2000-2006) and growth (2007-2013). Spatially, significantly increasing trends in NPP and WY were detected in 52.73% and 24.76% of the region, respectively, in areas that correspond with the Green for Grain project and high precipitation growth. Correlation and partial correlation analyses show that there were different dominant factors (i.e., natural vs. anthropogenic) driving ES change in the NSLP from 2000-2013. The change in WY was mainly driven by precipitation, while the improvements in GP and NPP can be attributed to investments in natural capital (i.e., chemical fertilizer, agricultural machinery power and afforestation). We also found that vegetation restoration can produce positive effects on NPP, but negative effects on WY by using response analyses of WY or NPP change to NDVI change, demonstrating that additional research on the role of water in vegetation restoration is needed. Our results provide support for ES management and the sustainable development of ecological restoration in the NSLP

Life Cycle Environmental Impact Assessment of Circular Agriculture: A Case Study in Fuqing, China

The process for reasonably evaluating the potential impacts of circular agriculture on the environment has become a key issue in the sustainable development of circular agriculture. Based on this consideration, by using Life Cycle Assessment (LCA) and focusing on the circular agriculture industry company of Xingyuan, Fuqing, this paper evaluates the potential impacts of the pig farming industry-dragon fruit planting-forage planting-fishery industry-mushroom planting-biogas generating-organic fertilizer production circular agriculture model compared to a main agriculture industrial model, the pig farming industry, from environmental and environmental-economic perspectives. Moreover, this paper determines key elements that restrict the development of circular agriculture through a sensitivity analysis. The results show that if we simply consider the potential environmental impacts, circular agriculture does not produce better results than those of the main agricultural production model. In addition, if we consider reducing the potential environmental impact as well as improving the economic benefits from the perspective of a &ldquo;reduction ring&rdquo;, we should consider removing mushroom planting and organic fertilizer from the circular agriculture framework. Moreover, if we want to reduce the potential environmental impact without changing the current recycling model, we should focus on the premix components, especially the three main components of corn, soybean meal, and whey protein concentrate