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Carbon farming has become increasingly popular as it integrates agriculture, forestry, and diverse land use practices, all crucial for implementing European strategies aimed at capturing 310 million tons of carbon dioxide from the atmosphere. These farming methods were proven to reliably increase the amount of carbon stored in the soil. However, there is a lack of discussion and consensus regarding the standards used to report these values and their implications. This article analyzes carbon sequestration rates, calculation methodologies, and communication procedures, as well as potential co-benefits and best practices. The average carbon sequestration rates in major staple crops range from very low values (0–0.5 Mg/ha/yr) to medium values (1–5 Mg/ha/yr). Scientific agricultural experiments in key global staple crops demonstrate positive rates of 4.96 Mg C ha−1 yr−1 in wheat–maize rotations and 0.52–0.69 Mg C ha−1 yr−1 in rice–wheat rotations. In agriculture, carbon sequestration rates are reported using different terms that are not consistent and pose communication challenges. This assessment involves a systematic review of the scientific literature, including articles, reviews, book chapters, and conference papers indexed in Scopus from 2001 to 2022. Specifically, this review focuses on long-term experiments, meta-analyses, and reviews that report an increase in soil carbon stock. The research trends observed, through a VOSviewer 1.6.18 analysis, show a steadily increasing interest in the field of carbon sequestration. [ABSTRACT FROM AUTHOR]

The main priority at wastewater treatment plants (WWTPs) is the attainment of a high quality of treated effluent ensuring the highly effective removal of pollutants and protecting the environment and public health. However, WWTPs are made of energy-intensive processes and consequently, they are considered major energy consumers in the public sector. The need to move towards energy neutrality in the wastewater sector was recently pointed out by the proposal of a recast Urban Wastewater Treatment Directive. To date, a comprehensive methodology for energy audits at WWTPs is still missing. The present review aims at discussing the state of the art on energy consumption at WWTPs and at surveying the energy benchmarking methodologies currently available highlighting the main advantages and limitations. It was pointed out that aeration represents the highest energy-intensive compartment in WWTPs (40–75% of total energy). The wide overview provided by key performance indicators (KPIs) might be overcome by applying benchmarking methodologies based on data envelopment analysis (DEA). The latest is properly designed for WWTPs and able to manage multiple inputs and outputs. However, the obtained findings are often limited and fragmented, making the standardization of the methodology difficult. Consequently, future investigations are advised on the development of standard procedures related to data acquisition and collection and on the implementation of online and real-time monitoring. Considering the lack of standardized methodology for the energy benchmarking of WWTPs, the present article will provide essential information to guide future research, helping WWTP utilities to reach the energy audit goals in the accomplishment of incoming EU directives. [ABSTRACT FROM AUTHOR]