Heavy metal loss from agricultural watershed to aquatic system: A scientometrics review

A Bibliometric Analysis of Research on Acid Rain

With the continuation of industrialization and urbanization, acid rain (AR) has aroused extensive concern because of its potential negative effects on ecosystems. However, analysis of the current status and development trends in AR research area has seldom been systematically studied. Therefore, we motivated to conduct a bibliometric analysis of AR publications (1900–2018) using HistCite and CiteSpace software programs. Compared to traditional reviews by experts, this study offers an alternative method to quantitatively analyze and visualize the development of AR field at a large time scale. The results indicated that the overall concern of AR research studies had increased from 1900 to 2018. The most productive country was the United States, while the institution with the most publications was Chinese Academy of Sciences. “Environmental Sciences” was the most popular subject category, Water, Air, and Soil Pollution was the dominant journal, and C.T. Driscoll was the most prominent author in AR field. There were three hotspots in the field of AR, including analyzing AR status and its control policies in Europe, the United States, and China in the past few decades, investigating the ecological consequences of AR on plant histological, physiological, and biochemical traits, as well as surface water and soil properties, and the model application for quantitatively assessing AR and its effects on terrestrial and aquatic ecosystems at regional scale. Further, “behavior”, “phosphorus”, “fractionation”, “soil acidification”, “corrosion”, “performance”, “recovery”, “rainwater”, “trace element”, and “surface water” have been emerging active topics in recent years. This study can help new researchers to find out the most relevant subject categories, countries, institutions, journals, authors, and articles, and identify research trends and frontiers in the field of AR.

Features, Driving Forces and Transition of the Household Energy Consumption in China: A Review

Household energy consumption has been a major contributor to the increase in global energy demand and carbon emission, and the household sector has also become one of the most crucial factors shaping the management of developments towards sustainability. However, there is still a knowledge gap regarding the household energy consumption in China. Due to the vast territory and the differences among regional conditions, it is critical to conduct a systemic review to illustrate the overall situation as well as the detailed mechanisms of the household energy consumption in China. By employing both qualitative and quantitative methods, two key features of the household energy consumption in China are presented; one is regarding the total amount and the structure of the household energy consumption, and the second is the significant urban-rural gap. The driving forces are investigated from the perspective of external determinants and internal determinants, which consist of seven key factors; finally, the transition roadmap towards the sustainable energy system for the household level are presented based on the text analysis from the four key policy documents. Weaknesses in the current research on the energy geography of household level also exist, such as the lack of single factor research and the lack of integration and comprehensive analysis. Therefore, future studies need to strengthen the research of regional household energy consumption structure, spatial-temporal process, and its motivation mechanism, and sustainable development of energy, so as to explore space-social structure of household energy consumption and spatial-temporal interaction.

Response Surface Methodology for the Optimisation of Electrochemical Biosensors for Heavy Metals Detection

Herein, we report the application of a chemometric tool for the optimisation of electrochemical biosensor performances. The experimental design was performed based on the responses of an amperometric biosensor developed for metal ions detection using the flow injection analysis. The electrode preparation and the working conditions were selected as experimental parameters, and thus, were modelled by a response surface methodology (RSM). In particular, enzyme concentration, flow rates, and number of cycles were reported as continuous factors, while the sensitivities of the biosensor (S, µA·mM-1) towards metals, such as Bi3+ and Al3+ were collected as responses and optimised by a central composite design (CCD). Bi3+ and Al3+ inhibition on the Pt/PPD/GOx biosensor response is for the first time reported. The optimal enzyme concentration, scan cycles and flow rate were found to be 50 U·mL-1, 30 and, 0.3 mL·min-1, respectively. Descriptive/predictive performances are discussed: the sensitivities of the optimised biosensor agreed with the experimental design prediction. The responses under the optimised conditions were also tested towards Ni2+ and Ag⁺ ions. The multivariate approach used in this work allowed us to obtain a wide working range for the biosensor, coupled with a high reproducibility of the response (RSD = 0.72%).

Review: Environmental impact of livestock farming and Precision Livestock Farming as a mitigation strategy

This paper reviews the environmental impact of current livestock practices and discusses the advantages offered by Precision Livestock Farming (PLF), as a potential strategy to mitigate environmental risks. PLF is defined as: "the application of process engineering principles and techniques to livestock farming to automatically monitor, model and manage animal production". The primary goal of PLF is to make livestock farming more economically, socially and environmentally sustainable and this can be obtained through the observation, interpretation of behaviours and, if possible, individual control of animals. Furthermore, adopting PLF to support management strategies, may lead to the reduction of the environmental impact of farms. Currently, few studies reported PLF efficacy in reducing the environmental impact, however further studies are necessary to better analyze the actual potential of PLF as a mitigation strategy. Literature shows the potentiality of the application of PLF, as the introduction of PLF in farms can lead to a reduction of Greenhouse gases (GHG) and ammonia (NH3) emission in air, nitrates and antibiotics pollution in water bodies, phosphorus, antibiotics and heavy metals in the soil.

Bibliographic and visualized analysis of geopolymer research and its application in heavy metal immobilization: A review

Geopolymer (GP) is a novel aluminosilicate inorganic polymer, and it possesses excellent characteristics in application of various fields, and its advantages have attracted worldwide attention. Based on the Citespace software, the bibliometric analysis combined with the visualization analysis on GP was summarized on the publications that extracted from Web of Science (WOS) from 1990 to 2017. The analysis results demonstrate that the research on GP develops rapidly in the last years, and the GP have already possessed a degree of application value in several engineering fields. This research shows a multidisciplinary amalgamation tendency in contents and methods. Additionally, the main application in pollution treatment of GP is heavy metal immobilization. The immobilization effects of GP for heavy metal are mainly depended on physical encapsulation, adsorption effect, chemical bonding, substitution for Al3+ and other effects. And these effects are simultaneous action on heavy metal immobilization under different conditions. Furthermore, the majority of GP are based on the fly ash and metakaolin, and the most frequently used leaching method is the Toxicity Characteristic Leaching Procedure (TCLP). Moreover, there are also several problems need to be solved before GP can be widely applied in heavy metal treatment. Overall, GP have possessed a great potential research and application value in the present stage, especially in the aspect of heavy metal immobilization.