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The intensified development of aquaculture and excessive use of agricultural fertilizers pose a threat to natural resource availability and deteriorate the environment. Utilizing aquaculture wastewater from mariculture for agricultural irrigation can mitigate pollution and alleviate the pressure on natural resources. This study investigated the comprehensive benefits of using freshwater and mariculture wastewater for irrigation, employing two concentration levels of mariculture wastewater in a pot experiment with saline-tolerant rice. Furthermore, we quantitively assessed the integrated benefits for farmland by utilizing an ecosystem service function value assessment and emergy value theory. The results indicate a significant enhancement in the growth and yield of saline-tolerant rice when irrigated with mariculture wastewater. Specifically, the theoretical yield increased by 9.01% relative to freshwater irrigation. Irrigation using aquaculture wastewater significantly enhanced the nutrient concentrations in the soil, including soil organic carbon (SOC), avail-K (AK), Olsen-P (OP), and alkali-N (AN). Additionally, the uptake of these nutrients by salt-tolerant crops during their late reproductive stage effectively mitigated the rise in soil salinity induced by the wastewater irrigation practice. Under experimental conditions, wastewater irrigation conferred superior ecological benefits compared with freshwater irrigation. The comprehensive benefits of wastewater irrigation, valued at 104,439.10 RMB/hm2, exceeded those of freshwater irrigation by 188.8%. The utilization of mariculture wastewater effectively enhances the coastal environment, augments crop yields, and diminishes treatment costs. From the perspectives of revenue enhancement, environmental compatibility, and sustainability, the model of utilizing salt-tolerant crops irrigated with mariculture wastewater holds substantial promotional and practical significance. [ABSTRACT FROM AUTHOR]

• We discussed on calculation approaches of human transformity. • We treated the transformity of teachers as a variable in the equation. • Results for human transformity needed comparisons and discussions. Human transformities are important for emergy accounting of human labor contributions in ecological, economic, and social systems. Lupinacci and Bonilla (2018) explored two different approaches to calculating teacher transformities in an English Language school in Minas Gerais, Brazil. This letter is not to criticize their approach and result, but instead to suggest one minor but potentially valuable amendment to their method. The innovation is to treat the transformity of the teacher as a variable on the input side of the equation. The new computed transformity of 1.21 E9 sej/J was 3.5 times larger than the transformity calculated by Lupinacci and Bonilla (2018). This E9 result is in line with other research that applied a multi-year cyclic calculation. The algebraic solution is one that could be applied more generally to other similar transformity equations. [ABSTRACT FROM AUTHOR]

Abstract: Sustainability evaluation of mariculture is needed for policy decision-making in its development. Zhao et al. (2013) developed the method of emergy ecological footprint to evaluate an offshore small fish farm in the East China Sea. After re-examination of their method, data analysis process and results, three questions are presented (1) what is the nature of this method? (2) How much impact do the recognition and classification of input flows on the results? (3) Do their evaluated results confirm to the real situation of this farm? Further discussions are also made on several main studies about the emergy ecological footprint method. Our results imply: (1) there is a need to improve this method; (2) the input flows should be carefully processed due to their great impacts on the results; (3) the essential data and comparative analysis are needed to support this evaluation. [Copyright &y& Elsevier]

Abstract Sustainability evaluation of land resources could help policy decision-making in land use planning and management in a region. Zhang et al. (2018) presented a study on sustainability of land resources in Dengkou County based on emergy analysis. We commented on their major shortcomings including limitations of the energy system diagram, lacks of the emergy accounting of water resources, soil losses, machinery, environmental pollution and control, and the results of dynamic simulation. It is concluded that the emergy analysis method could serve land sustainability analysis, but it is of vital importance to create normative system diagrams and select proper emergy accounting items and dynamic simulation methods for ensuring the validity of evaluation results. Highlights • We commented on limitations of a land resources emergy analysis by Zhang et al. (2018). • Energy Systems Language should be normatively used. • Selection of emergy accounting items is of vital importance. • Land use change and emergy analysis need proper dynamic simulation methods. [ABSTRACT FROM AUTHOR]

A bibliometric approach, along with Citespace software, was used to quantitatively and visually evaluate global scientific research on emergy from 1996 to 2014. 637 publications – in accordance with the search criteria from the Science Citation Index Expanded (SCI-Expanded) and Social Science Citation Index (SSCI) of the Web of Science database – were statistically analyzed. The assessments on document type and language, publication year, authorship, subject categories and journals, countries/territories and institutions, most-frequently cited publications and author keywords were conducted with respect to seven categories. The amount of emergy publications per year has sharply increased in recent years. The most productive author was S. Ulgiati with 50 articles, who was also one of the most frequently cited publication authors. China produced 35.95% of all pertinent publications followed by the USA with 25.59% and Italy with 21.66%. Ecological Modeling, Ecological Engineering and Ecological Indicators were the three most common journals in this field. By synthetically analyzing the keywords, the dominant hot spots of emergy research could be concluded as “energy”, “sustainability”, “transformity”, and “indicators”. [ABSTRACT FROM AUTHOR]