Does circular economy performance lead to sustainable development? - A systematic literature review.

The paper provides a systematic literature review to investigate whether circular economy (CE) performance in the technical cycle will contribute to the sustainable development. Two academic databases, namely Scopus and Web of Science were used to retrieve research papers which span over the period 2000-2019. The research articles were classified according to the Sustainable Development Goals (SDG's) addressed, industries involved, key areas of CE, pillars of sustainability, CE principles (R-Imperatives and Systems perspective), type of cycle in CE, and transversality (generic, product-specific and sector-specific). The review highlights various research gaps concerning the proposed classification. The research gaps will provide new emerging areas to the CE and will help to align the CE performance with the SDGs.

Chromium-induced alterations in photosynthesis and associated attributes in Indian mustard.

Contamination of soil and water by chromium (Cr) is increasing enormously due to anthropogenic activities. The potential of plants to accumulate or stabilize Cr compounds forthe purpose of remediation of Cr contamination has been recognized in recent years. We conducted pot experiments to study photosynthesis and associated attributes in cv Pusa Jai Kisan of Indian mustard under natural as well as Cr-loaded environmental conditions. High doses of Cr caused toxic effects in plants, as evident by a reduction in photosynthetic rate (24.3 to 8.7 micromol CO2 m(-2)s(-1) at 80 DAS), nitrate reductase activity (3.76 to 1.30 micromol nitrite g(-1) f. wt. h(-1) at 80 DAS) and the contents of chlorophyll (1.49 to 0.86 mg g(-1) f. wt. at 80 DAS) and soluble protein (2.96 to 1.93 mg g(-1) f. wt. at 80 DAS). Since plants lack a specific Cr-transport system, mineral nutrient contents also changed due to Cr toxicity. Cr accumulation in different plant parts was affected by both duration and dose of Cr treatments, with a maximal localization of Cr in roots (up to 0.77 mg g(-1) d. wt) at initial stages (40 DAS) and in stem (up to 4.19 mg g(-1) d. wt) at the later stage (80 DAS) of plant growth. Thus, Indian mustard was able to withstand Cr stress and protect itself from Cr toxicity by altering various metabolic processes. Owing to its ability to accumulate large amounts of Cr, it may be useful in the process of land reclamation.

Reconceptualizing INRM in understanding environmental risks from food production systems.

Sustainable agri-development is composed of soil fertility maintenance, nutrient use efficiency and resource use efficiency. In this regard, the present study aims to address the complex dynamics of farm-soil and the water nexus for integrated natural resource management by understanding the fertilizer use decision of farmers. In addition to the monitoring of soil quality parameters, that is, the total nitrogen and nitrate concentrations, factor analysis was used to explore the drivers of high fertilizer use in the most agriculturally intensive region of India. The results classified economic benefits, intrinsic and extrinsic motivations, resource-related aspects, institutional set-up and passivity towards environmental quality as major entry points for integrated natural resource management. Although the economic benefit in the form of the affordability of nitrogenous fertilizers was found to be the most critical rationale for fertilizer use, passivity towards environmental quality emerged as a factor of interest. Because short-term economic benefits outweigh concerns for environmental quality, our research suggests that outreach educational programs on sustainable farm practices can be instrumental in resource management. Support of the farming community by governmental/non-governmental agricultural agencies to formulate site-specific recommendations can significantly mitigate fertilizer-induced non-point pollution.

Chromium-induced modulation in the antioxidant defense system during phenological growth stages of Indian mustard.

Chromium-induced modulation in the enzymes and metabolites of antioxidants was investigated at various phenological stages of Indian mustard (Brassica juncea (L.) Czern. & Coss. cv Pusa Jai Kisan)], grown with various levels of chromium (Cr) in pots under natural environmental conditions. Chromium accumulation in the root, stem and leaves increased with the advancement in the age of the plants. Growth of Indian mustard was not affected significantly by the supply of Cr up to the levels of 400 mg kg(-1) soil. Activities of superoxide dismutase (SOD), ascorbate peroxide (APX), catalase (CAT), and glutathione reductase (GR) increased in the leaves of Cr-treated plants, when compared with control. High activities of antioxidant enzymes supported by high Cr concentrations in roots and aerial parts (except seeds) established the Indian mustard as a potential hyperaccumulator anda hypertolerant species to Cr stress. For this study, an edible crop was chosen intentionally so as to tap maximum benefit by remediating the contaminated site on one hand and getting uncontaminated seeds to raise the next generation, on the other.

Genotypic variation in the phytoremediation potential of Indian mustard for chromium.

The term "phytoremediation" is used to describe the cleanup of heavy metals from contaminated sites by plants. This study demonstrates phytoremediation potential of Indian mustard (Brasicca juncea (L.) Czern. & Coss.) genotypes for chromium (Cr). Seedlings of 10 genotypes were grown hydroponically in artificially contaminated water over a range of environmentally relevant concentrations of Cr (VI), and the responses of genotypes in the presence of Cr, with reference to Cr accumulation, its phytotoxity and anti-oxidative system were investigated. The Cr accumulation potential varied largely among Indian mustard genotypes. At 100 microM Cr treatment, Pusa Jai Kisan accumulated the maximum amount of Cr (1680 microg Cr g(-1) DW) whereas Vardhan accumulated the minimum (107 microg Cr g(-1) DW). As the tolerance of metals is a key plant characteristic required for phytoremediation purpose, effects of various levels of Cr on biomass were evaluated as the gross effect. The extent of oxidative stress caused by Cr stress was measured as rate of lipid peroxidation. The level of thiobarbituric acid reactive substances (TBARS) was enhanced at all Cr treatments when compared to the control. Inductions of enzymatic and nonenzymatic antioxidants were monitored as metal-detoxifying responses. All the genotypes responded to Cr-induced oxidative stress by modulating nonenzymatic antioxidants [glutathione (GSH) and ascorbate (Asc)] and enzymatic antioxidants [superoxide dismutase (SOD), ascorbate peroxidase (APX), and glutathione reductase (GR)]. The level of induction, however, differed among the genotypes, being at its maximum in Pusa Jai Kisan and its minimum in Vardhan. Pusa Jai Kisan was grown under natural field conditions with various Cr treatments, and Cr-accumulation capacity was studied. The results confirmed that Pusa Jai Kisan is a hyperaccumulator of Cr and hypertolerant to Cr-induced stress, which makes this genotype a viable candidate for use in the development of phytoremediation technology of Cr-contaminated sites.