Mechanism of photodegradation over BiVO₄/Bi₂WO₆ composite photocatalyst under visible light irradiation.

Salt stress is a major problem happening in almost all the world, affecting soil metabolism and acting further negatively soil fertility and soil quality, causing land degradation and low ecosystem service functions and ecosystem productivity. In marshy area as one type of important marginal land resources, salt is also the main barrier to be improved and the driving force to make vegetation succeed. This commentary briefly reviews the main advance focusing on salt‐affected soil and introduced the publications in this Special Issue: Salt Soil Improvement and Efficient Development in Land Degradation & Development 29, 2018, to promote global cooperation for studying salt‐affecting soil quality, land degradation, and eco‐restoration.

As the energy demand increases, there is a significant expansion and utilization of oil resources, resulting in the inevitable occurrence of environmental pollution. Oil has been identified as a prevalent soil contaminant, posing substantial risks to the soil ecosystems. The remediation of soil contaminated with oil is a formidable undertaking. Increasing evidence shows that chemical washing, a remediation technique employing chemical reagents like surfactants to augment the solubilization, desorption, and separation of petroleum hydrocarbons in soil, proves to be an efficacious approach, but the latest advances on this topic have not been systematically reviewed. Here, we present the state of knowledge about the surfactant-based chemical washing to remediate oil-contaminated soil. Using the latest data, the present article systematically summarizes the advancements on ex situ chemical washing of oil pollution and provides a concise summary of the underlying principles. The use of various surfactants in chemical washing and the factors influencing remediation efficiency are highlighted. Based on the current research status and knowledge gaps, future perspectives are proposed to facilitate chemical washing of oil-polluted soil. This review can help recognize the application of chemical washing in the remediation of oil-polluted soil.

The salinization of several hundred million hectares of land poses a serious threat to global food security and biodiversity. Biochar and wood vinegar amendment has been suggested as a possible way to promote plant productivity and improve soil qualities, whereas less emphasis has been placed on the application of biochar in saline−alkaline soils to increase plant productivity. Herein, the single and composite application of sawdust biochar, wood vinegar, and acid-modified biochar on the restoration of coastal saline−alkali soil and plant growth of strawberry seedlings was investigated. Proximate and ultimate analyses and different characterization techniques such as FTIR and scanning electron microscopy were applied to study the physicochemical characteristics of raw and modified biochar. A pot experiment was conducted to explore the effects of different soil additives on soil properties and strawberry growth. Our results revealed that acid-modified biochar shows the most significant promoting effect on strawberry growth, which could increase the weight gain rate, root length, root specific surface area, and root volume of strawberry seedlings by 41.2%, 18.9%, 23.0%, and 34.7%, respectively. Moreover, the application of acid-modified biochar can effectively alleviate soil salinization by reducing soil pH (7.65) and CEC (19.5 cmol/kg). Furthermore, the addition of biochar can significantly improve the community structure of microorganisms (Proteobacteria) and increase the content of bacteria related to soil nutrient cycling (Pseudomonadaceae and Sphingomonadaceae). Preliminary findings from this study suggested that acid-modified biochar is a potentially effective means of preventing soil salinization and increasing economic crop yields.