India, the second largest agro-based economy with year-round crop cultivation, generates a large amount of agricultural waste, including crop residues. In the absence of adequate sustainable management practices, approximately 92 seems a very small number of metric tons of crop waste is burned every year in India, causing excessive particulate matter emissions and air pollution. Crop residue burning has become a major environmental problem causing health issues as well as contributing to global warming. Composting, biochar production and mechanization are a few effective sustainable techniques that can help to curtail the issue while retaining the nutrients present in the crop residue in the soil. The government of India has attempted to curtail this problem, through numerous measures and campaigns designed to promote sustainable management methods such as converting crop residue into energy. However, the alarming rise of air pollution levels caused by crop residue burning in the city of Delhi and other northern areas in India observed in recent years, especially in and after the year of 2015, suggest that the issues is not yet under control. The solution to crop residue burning lies in the effective implementation of sustainable management practices with Government interventions and policies. This manuscript addresses the underlying technical as well as policy issues that has prevented India from achieving a long-lasting solution and also potential solutions that have been overlooked. However, effective implementation of these techniques also requires us to look at other socioeconomic aspects that had not been considered. This manuscript also discusses some of the policy considerations and functionality based on the analyses and current practices. The agricultural waste sector can benefit immensely from some of the examples from other waste sectors such as the municipal solid waste (MSW) and wastewater management where collection, segregation, recycling and disposal are institutionalized to secure an operational system. Active stakeholder involvement including education and empowerment of farmers along with technical solutions and product manufacturing can also assist tremendously. Even though the issue of crop residue burning touches many sectors, such as environment, agriculture, economy, social aspects, education, and energy, the past governmental efforts mainly revolved around agriculture and energy. This sectorial thinking is another barrier that needs to be broken. The government of India as well as governments of other developing countries can benefit from the emerging concept of nexus thinking in managing environmental resources. Nexus thinking promotes a higher-level integration and higher level of stakeholder involvement that goes beyond the disciplinary boundaries, providing a supporting platform to solve issues such as crop residue burning.

Municipal Solid Waste (MSW) management is an essential service for an urban population to maintain sanitation. Managing MSW is complex as the treatment/recovery options depend not only on the volume of waste, but also on the socioeconomic conditions of the population. This paper focusses on MSW management in the Latin American and Caribbean (LAC) countries. Dominance of uncontrolled disposal options of MSW in the region, such as open dumps, has an adverse influence on health and sanitation. Interest in source separation practices and recycling is low in the LAC region. Furthermore, economic matters such as poor financial planning and ineffective billing systems also hinder service sustainability. Rapid urbanization is another characteristic feature in the region. The large urban centres that accommodate over 80% of the region’s population pose their own challenges to MSW management. However, the same large volume of MSW generated can become a steady supply of resources, if recovery options are prioritized. Governance is one aspect that binds many activities and stakeholders involved in MSW management. This manuscript describes how we may look at MSW management in LAC from the governance perspective. The issues, as well as the best potential solutions, are both described within three categories of governance: bureaucratic, market, and network. The governance perspective can assist by explaining which stakeholders are involved and who should be responsible for what. Financial issues are the major setbacks observed in the bureaucratic governance institutions that can be reversed with better billing strategies. MSW is still not seen by the private sector as a place to make investments, perhaps due to the negative social attitude associated with waste. The market governance aspects may help increase the efficiency and profitability of the MSW market. Private sector initiatives such as cost-effective microenterprises should be encouraged and the projects that fit under the Clean Development Mechanism (CDM) defined in the Kyoto Protocol should be incentivized to attract technology and capital. Lastly, network governance is at the centre of attention due to its flexibility in supporting/absorbing public-private partnerships, especially the participation of the informal sector that is important to the LAC region. Many individual waste pickers are providing their services to the LAC region by taking part in collecting and recycling under very unfavourable working conditions.

Many developing countries have inadequate Municipal Solid Waste (MSW) management systems due to lack of not only the awareness, technologies, finances, but also a proper governance that is able to enforce and monitor the regulations. Not all the solutions practiced by and in developed countries fit to the developing country contexts. The local conditions and limitations must always be taken into account when proposing waste management options for developing countries. The excessively high organic waste fraction in MSW and relatively inexpensive labor markets available in developing countries are two of the strengths that have not yet been utilized fully. This manuscript is an attempt to point out the benefits we receive from the above two strengths if we establish organic waste buyback programs. This can only become successful if we find solutions to: (1) collect source-separated organic waste, and then (2) find stable markets for the products made from organic waste. Compost or biogas could be the best bet developing countries can consider as products. However, there must be some policy interventions to support buyback programs at the waste collection stage as well as at the product marketing stage. Implementation of such organic waste buyback centers that can offer some incentives can indirectly motivate residents to do source separation. This will in turn also help promote more recycling, as any waste bin that has no organics in it is much easier for anyone (e.g., waste pickers) to look for other recyclables. Developing country settings such as the Green Container composting program in Cajicá, Colombia, and buyback centers in South Africa that are presented later in the manuscript are thought to be the places where the concept can be implemented with little effort. The environment, economy, and society are considered to be the three dimensions (or pillars) of sustainability. Interestingly, the organic waste buyback centers solution has positive implications on all three aspects of sustainability. Thus, it also supports the 2030 Agenda of the United Nations (UN), by making specific contributions to the Sustainable Development Goals (SDGs) such as zero hunger (SDG 2), affordable and clean energy (SDG 7), climate action (SDG 13), clean water and sanitation (SDG 6), and sustainable cities and communities (SDG 11).

Plastic materials that are less than 5 mm in size are defined as Microplastics (MPs). MPs that are intentionally produced are called primary MPs; however, the most abundant type in the environment consists of the remainder created by the fragmentation of large plastic debris through physical, chemical, and oxidative processes, which are called secondary MPs. Due to their abundance in the environment, poor degradability, toxicological properties, and negative impact on aquatic and terrestrial organisms, including humans, MP pollution has become a global environmental issue. Combatting MP pollution requires both remediation and preventive measures. Although remediation is a must, considering where the technology stands today, it may take long time to make it happen. Prevention, on the other hand, can be and should be done now. However, the effectiveness of preventive measures depends heavily on how well MP escape routes are researched and understood. In this research, we argue that such escape routes (rather, loopholes) exist not only due to mismanaged plastic waste, but also due to cracks in the current waste management systems. One known MP loophole is facilitated by wastewater treatment plants (WWTP). The inability of existing WWTP to retain finer MPs, which are finally released to water bodies together with the treated wastewater, along with the return of captured larger MPs back to landfills and their release into the environment through land applications, are a few examples. Organic waste composting and upcycling of waste incineration ash provide other MP escape pathways. In addition, it is important to understand that the plastics that are in current circulation (active use as well as idling) are responsible for producing MPs through regular wear and tear. Closing these loopholes may be best attempted through policy interventions.

Recycling and recovery provide not only a sustainable option to decrease the volume of waste that needs final disposal, but also a blueprint to a circular economy. However, rates of recycling/recovery still remain very low on a global scale. While it is important to look for technology-based solutions to improve recycling/recovery activities, such solutions might not be necessarily affordable in many countries. A solution that involves the active participation of the population, on the other hand, has the potential to succeed in any country. The challenge is to attract and unite people to achieve such common goals. The theory of collective action and the Institutional Analysis and Development (IAD) framework, that have been originally used in resource management, are two concepts that can be adapted to organize recycling/recovery initiatives. This manuscript discusses what recycling/recovery programs can learn from the theory of collective action and the IAD framework, through a qualitative comparative study of such initiatives from three different cities. They are; Curitiba in Brazil, Padang in Indonesia, and Akure in Nigeria. The cases show the potential benefits of both concepts, not only in formulating and implementing recycling/recovery programs but also in making corrective measures for continuous improvements. All cases also showed the importance of increasing awareness-raising to change public perception towards waste from being a nuisance to a valuable resource.