Incidence of microplastic contamination in fishes of the Ramsar Wetland, Loktak - The world's only floating lake from the Indian Himalayan region.

Microplastics are ubiquitous, and their widespread prevalence in the ecosphere has generated concerns about their potential effects on terrestrial and aquatic organisms. However, studies pertaining to ecologically sensitive freshwater ecosystems, such as Ramsar wetlands, is scarce. Therefore, the study was conducted in Loktak, the world's only floating lake, and one of the largest wetland in the Indian Himalayan region. The wetland's degradation and pollution have resulted its inclusion in the Montreux Record, underscoring the need for studying this eco-sensitive freshwater system. This work investigated the (i) abundance, morphotype and size of microplastics in fish, and (ii) chemical composition of the microplastics consumed and accumulated in the fish of Loktak lake. Fish samples representing eight species were collected and analyzed for microplastics. Results revealed that ∼91% of the sampled fish ingested microplastics. Fragment was identified as the predominant morphotype (∼82%). Plastic polymers including polyamide (PA), polystyrene (PS), polycarbonate (PC) and carboxymethyl cellulose (CMC) were detected. The occurrence of heavy metals - chlorine (Cl), palladium (Pd), sodium (Na), zinc (Zn), lead (Pb) and copper (Cu) suggests their adhesion on the microplastics. The occurrence of microplastics in fish indicates pollution in the lake and poses a potential health risks to humans through consumption. Therefore, implementing comprehensive management approaches is imperative to mitigate this emerging pollution and uphold the ecological integrity of the Ramsar site. Substantial information on microplastics and their potential human exposure through fish consumption, particularly in the Indian Himalayan region, remains to be assessed, underscoring the need for extensive study.

Geochemical fractionation of iron in paper industry and municipal landfill soils: Ecological and health risks insights.

Industrial processes and municipal wastes largely contribute to the fluctuations in iron (Fe) content in soils. Fe, when present in unfavorable amount, causes harmful effects on human, flora, and fauna. The present study is an attempt to evaluate the composition of Fe in surface soils from paper mill and municipal landfill sites and assess their potential ecological and human health risks. Geochemical fractionation was conducted to explore the chemical bonding of Fe across different fractions, i.e., water-soluble (F1) to residual (F6). Different contamination factors and pollution indices were evaluated to comprehend Fe contamination extent across the study area. Results indicated the preference for less mobile forms in the paper mill and landfill, with 26.66% and 43.46% of Fe associated with the Fe-Mn oxide bound fraction (F4), and 57.22% and 24.78% in the residual fraction (F6). Maximum mobility factor (MF) of 30.65% was observed in the paper mill, and 80.37% in the landfill. The enrichment factor (EF) varied within the range of 20 < EF < 40, signifying a high level of enrichment in the soil. The individual contamination factor (ICF) ranged from 0 to >6, highlighting low to high contamination. Adults were found to be more vulnerable towards Fe associated health risks compared to children. The Hazard Quotient (HQ) index showed the highest risk potential pathways as dermal contact > ingestion > inhalation. The study offers insights into potential Fe contamination risks in comparable environments, underscoring the crucial role of thorough soil assessments in shaping land use and waste management policies.

The Shifting Cultivation Juggernaut: An Attribution Problem.

Shifting cultivation entails clearing a delimited land and transforming it into arable land. Owing to its complexity, this system has been a subject of debate and intervention since the colonial-era, and is often considered as the "tropical deforestation culprit." Shifting cultivators are often labeled as "forest eaters" and are considered backward and primitive. Opponents of shifting cultivation often attribute the loss of forest cover to shifting cultivation, and favor intensification, claiming that commercial plantations are more productive. However, attempts to replace it have often failed due to inadequate understanding of the system and the decision-making processes involved. On the other hand, a growing body of literature provides evidence that shifting cultivation is an ecologically and economically efficient practice. After a careful review of the literature, the authors conclude that the dichotomy of opinions is the consequence of the attribution problem. The authors also argue that the management of forest ecosystems will be challenging if policy and practice are not based on careful understanding of the power of this age-old practice. Hence, there is a need for a careful diagnosis of this system and a rethink before claiming that the system is unsustainable and attempting to replace it with practices such as plantations.

Post-fire restoration of land under shifting cultivation: A case study of pineapple agroforestry in the Sub-Himalayan region.

Access to the knowledge associated with traditional and/or indigenous land-use systems can help develop adaptive strategies, more productive systems and, design sustainable development models and technologies. This article describes the evolution of traditional pineapple (Ananas comosus) agroforestry systems (PAFS) developed by the ethnic Hmar communities as a strategy for the restoration of land under slash-and-burn agriculture in the Sub-Himalayan region. We critically examine the social and ecological perspectives on rural livelihoods and environmental management, and documented the native tree species managed under different age groups of PAFS. We also interviewed farm managers to gain insights into the traditional farming practices and the uses and services of the different multipurpose tree species (MPTs) along with their traditional management. The study showed that PAFS are an integral part of the rural landscape in the study region exemplifying unique agroforestry systems that have evolved as a strategy to improve land under slash-and-burn on hilly landscapes. PAFS are post-fire sedentary systems evolving as a by-product of shifting agriculture. The system combines pineapple crops with remnant fallow vegetation and subsequent plantations of cash-oriented MPTs in the same farmland. MPTs such as the critically endangered Aquilaria malaccensis and the economically important tree bean (Parkia timoriana), which is no longer found in the wild are largely conserved in the PAFS. Our study demonstrates that PAFS can play a vital role in post-fire restoration of land under slash-and-burn agriculture, which is still practiced among many tribes in the Indian Eastern Himalayas.

Assessing tree diversity and carbon storage during land use transitioning from shifting cultivation to indigenous agroforestry systems: Implications for REDD+ initiatives.

Indigenous agroforestry systems are important reservoirs of biodiversity, and ecosystem services with a potential contribution for conservation of biodiversity while sustaining the livelihood of the rural populace. Pineapple (Ananas comosus) agroforestry systems (PAFS) form an essential constituent of the rural landscape in the Indian Eastern Himalayas and other parts of Asia. The traditional PAFS management in southern Assam is unique in that it involves shifting cultivation transitioning from native forests to a PAFS. Scarcity of information on the functioning and services in terms of species diversity and carbon storage potential in the traditional PAFS has restricted the opportunities for consideration under the nature-based solutions of climate action including REDD+. Therefore, the present study assessed the tree diversity and ecosystem carbon storage in a chronosequence from swidden agriculture through different phases of PAFS establishment. The result demonstrated that basal area in the PAFS increased with age. The most dominant species in the native forests was Palaquium polyanthum, while agricultural land use and PAFS aged <5, 11-15 and > 15 years old were dominated by Gmelina arborea, Albizia procera, Areca catechu and Hevea brasiliensis, respectively. The highest value of Shannon-Wiener diversity index (H) was recorded in native forests (2.71), and lowest in 5-10 years old PAFS. The ecosystem carbon storage declined from 261.43 Mg ha-1 in native forests to 181.07 Mg ha-1 in <5-years old PAFS. In <5 years old PAFS, the ecosystem carbon storage was 30 % lower than the native forest; while at >15 years it was merely 5 % less than the native forests. The traditional PAFS maintains a steady ecosystem carbon stock while reducing land use related carbon emission and providing additional co-benefits to the communities. Therefore, the traditional PAFS constitute a good opportunity for REDD+.

Coupled human-environment system amid COVID-19 crisis: A conceptual model to understand the nexus.

The world today is dealing with a havoc crisis due to the pervasive outbreak of COVID-19. As a preventive measure against the pandemic, government authorities worldwide have implemented and adopted strict policy interventions such as lockdown, social distancing, and quarantine to curtail the disease transmission. Consequently, humans have been experiencing several ill impacts, while the natural environment has been reaping the benefits of the interventions. Therefore, it is imperative to understand the interlinked relationship between human society and the natural environment amid the current crisis. Herein, we performed a meta-analysis of existing literature reporting the various impacts of COVID-19 on human society and the natural environment. A conceptual model was developed to portray and address how the interaction of the existing elements of both sub-components of the coupled human-environment system (CHES) - human society and natural environment - are impacted by the government interventions. Results revealed a suite of positive and negative impacts of COVID-19 on both the sub-components. Our model provides an explicit impression of the complex nexus of CHES amid the current crisis. The proposed conceptual model could help in understanding the complex nexus by identifying the route of short-term impacts of COVID-19 measures and thus may aid in identifying priority areas for discussion and planning in similar crises as well.