Impact of Aerated Drip Irrigation and Nitrogen Application on Soil Properties, Soil Bacterial Communities and Agronomic Traits of Cucumber in a Greenhouse System.

Root hypoxia stress and soil nutrient turnover have been related to reduced crop productivity. Aerated drip irrigation (ADI) can effectively enhance crop productivity and yield. However, the response of the soil bacterial community to different irrigation water dissolved oxygen (DO) concentrations remains elusive due to the extreme sensitivity of microorganisms to environmental variations. We investigated the effects of aerated irrigation with different concentrations of DO on soil properties and agronomic performance of cucumber, as well as the contribution of the bacterial community. We performed experiments on cucumber cultivation in Shouguang, China, including different irrigation methods (ADI: O2-10 and O3-20 mg L-1, non-aerated groundwater: O1-5 mg L-1) and nitrogen (N) application rates: 240 and 360 kg N ha-1. ADI (particularly O2) significantly improved soil properties, root growth, cucumber yields, and irrigation water use efficiency (IWUE), and appropriate DO concentrations reduced N fertilizer application and increased crop yields. Furthermore, these changes were associated with bacterial community diversity, aerobic bacteria abundance, and consolidated bacterial population stability within the network module. Environmental factors such as soil respiration rate (Rs), DO, and NO3--N have significant effects on bacterial communities. The FAPROTAX results demonstrated enhanced nitrification (Nitrospira) and aerobic nitrite oxidation by soil bacteria under ADI, promoting the accumulation of effective soil N and improved soil fertility and crop yield. Appropriate DO concentration is conducive to the involvement of soil bacterial communities in regulating soil properties and cucumber growth performance, which are vital for the sustainable development of facility agriculture.

Dunaliella Salinas based Sn-carbon anode for high-performance Li-ion batteries.

Long life, high capacity, environmental friendliness and good rate performance are the most important elements in the research of lithium ion batteries (LIBs). In this paper, Sn-carbon composite electrode materials are prepared using Dunaliella Salinas based carbon (amorphous carbon) as an amorphous carbon precursor combined with tin. Hence, an amorphous carbon template enwrapped by Sn particles forms a core-shell structure (Sn-carbon composite), the annealed Dunaliella Salinas based carbon makes up the carbon core, and Sn particles form the shell of the material. The components of the materials, microstructure and electrochemical properties of LIBs were characterized and tested. The results show that the prepared Sn-carbon composite electrode materials have high purity and combine with amorphous carbon uniformly. The Sn-carbon composite exhibits excellent performance as a LIB anode, its discharge capacities of the 1st, 2nd, and 4th cycles are 1777.39, 944.15 and 722.46 mA h g-1 at a current density of 100 mA g-1, and the capacity is 619.09 mA h g-1 after stable cycling at a current density of 200 mA g-1. The capacity continues to rise at a high current density of 1000 mA g-1 and is 574.97 mA h g-1 at its maximum, demonstrating the excellent performance of the electrode.