Perspectives on Sustainable Integrated Clean Environment for Human and Nature

The term “sustainability” is generally used to describe an ideal condition in which the Earth’s biosphere and human civilization can safely interact and coexist [...]


Introduction
The term "sustainability" is generally used to describe an ideal condition in which the Earth's biosphere and human civilization can safely interact and coexist [1]. Accordingly, it is essential to have a comprehensive vision of the requirements for a clean environment sustainable by humans and nature. Such a vision can be useful as it encompasses all aspects related to human life that interact with nature, so that human civilization can develop while respecting and protecting nature.
However, there are limited scientific approaches to achieving this vision. To address this knowledge gap, in December 2019, the author proposed a Special Issue of the journal Sustainability (ISSN 2071-1050) entitled "Sustainable Integrated Clean Environment for Human & Nature", to gather the missing pieces of this vision among multidisciplinary scientific-technical, economic, and social approaches over a one-year period. The Special Issue attempts to answer the following key questions:

1.
What is the current condition of our environment? Is it clean and pollution-free? 2.
How can we make our environment clean and suitable for humans and nature? 3.
How can we sustainably keep our environment clean?
The articles in the Special Issue contribute to one or more of the following fields: • Resource circulation-conservation and recycling.

List of Contributions
Over 30 manuscripts were submitted for consideration for the Special Issue, and all of them underwent the journal's rigorous review process. In total, 19 papers, including 17 research articles and 2 review papers, were finally accepted for publication and inclusion in this Special Issue. These are listed below:

Content and Significance of Contributions
Shortly after the Special Issue was announced, the world faced one of the most serious outbreaks of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) [2]. In view of humanity's current lifestyle, the coronavirus disease (COVID-19) pandemic has shown the fragility of our concept of sustainability [3]. Consequently, the importance of the concept of "sustainable, clean environment" became clear to individuals around the world.
The COVID-19 pandemic has demonstrated the need for a crucial reconsideration of the need for a sustainable, clean environment for humans and nature. The provision of safe water, sanitation, hygiene, and waste management is essential for preventing virus transmission, and protecting human health has become increasingly critical. Understanding the technical, social, and economic concepts of the COVID-19 pandemic and recognizing challenges can lead to solutions and sustainable management approaches during and after the pandemic.
In response to the COVID-19 pandemic, contributions 1, 4, 10, 13, and 14 cover a wide range of topics related to the sustainability of an integrated clean environment. These contributions are useful in highlighting the novel meaning of sustainability after the COVID-19 pandemic.
Accordingly, the 4th Sustainability Webinar, "COVID-19 and the Sustainability of Clean Environment for Human & Nature: Visions, Challenges, and Solutions", was proposed to provide a global forum for ordinary individuals and decision-makers to understand the vision, challenges, and solutions for sustaining a clean environment for humans and nature during and after the COVID-19 pandemic. The webinar included presentations from four experts, including scholars who made relevant contributions to the Special Issue. A webinar recording is available online at https://sustainability-4.sciforum.net/ (accessed on 29 March 2021) [4].
Along with the medical approaches for overcoming the COVID-19 pandemic, implementing appropriate green technologies may be considered among the highest priorities for sustainable development during and after the COVID-19 pandemic.
The Special Issue contains two contributions on the topic of sustainable sanitation. Contribution 6 introduces the Sanitation Sustainability Index, which is an integrated, community-based indicator for evaluating the sustainability of sanitation systems, which will be implemented in specific communities. The highlighted characteristics of this newly developed index are the consideration of a wider range of sanitation sustainability parameters, including acceptability and public health indicators, and the ability of the index to evaluate sanitation systems before implementation [5].
Another notable contribution is presented by White et al. (contribution 18), who discussed national versus local sustainable development plans and island priorities in sanitation. This article provides examples from the Kingdom of Tonga and presents an analysis of the priorities given to water and sanitation in top-down national sustainable development strategies and nation-wide, bottom-up, village-level community develop-ment plans. This contribution has been commended by the editorial office of the journal Sustainability and has been recognized as a feature paper. Contributions 3,7, and 17 of the Special Issue present discussions on sustainable urban planning, green infrastructure, and academic policies. Contributions 2 and 19 discuss indoor and outdoor air quality from both technical and public health perspectives. In addition, contributions 15 and 16 present intriguing studies that discuss industrial concerns, including impacts on the environment and sustainable development policies. A significant number of studies, including contributions 5, 8, 9, 11, and 12, discuss different aspects of ecological concerns regarding environmental sustainability, including the technical approaches for the treatment or bioremediation of environmental contaminants.

Conclusions
The Special Issue "Sustainable Integrated Clean Environment for Human & Nature" is a collection of articles that investigate the technical, economic, and social shortcomings of the current approaches toward a sustainable integrated clean environment for humans and nature in developing countries; these articles also provide innovative solutions aimed at overcoming the challenges of balancing the current approaches to enhance their sustainability.
Consideration of these studies could be helpful for decision-makers seeking to develop efficient strategies leading to the provision of new and effective sustainability policies by considering both the social development of humans and the need to respect and protect nature sustainably.