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Macrophytes have the potential to withstand pollutant-induced stress and can be used to clean contaminated water using phyto-extraction, phyto-degradation, phyto-filtration, phyto-stimulation, and phyto-volatilization technique(s). Phytoremediation through constructed wetlands (CWs) for eliminating inorganic and organic pollutants from household sewage and wastewater has attracted scientific attention. CWs are artificially engineered treatment systems that utilize natural cycles or processes involving soils, wetland vegetation, and plant and soil-associated microbial assemblages to remediate contaminated water and improve its quality. Herein, we present a detailed assessment of contaminant removal effectiveness in different CW systems, i.e., free-water surface or surface-flow constructed wetlands (FWSCWs/SFCWs), subsurface-flow constructed wetlands (SSFCWs), and hybrid constructed wetlands (HCWs). Several wetland floral species have been reported as potential phytoremediators, effectively reducing aquatic contamination through biodegrading, biotransforming, and bioaccumulating contaminants. Water hyacinth (Pontederia crassipes) is one of the most resistant macrophytes, capable of tolerating high nitrate (NO3−) and phosphate (PO42−) concentrations. Other aquatic weeds also effectively alleviate biological oxygen demand (BOD), chemical oxygen demand (COD), total dissolved solids (TDS), and pathogen levels and ameliorate the impact of different ionic forms of nitrogen (N), phosphorus (P), and trace elements (TEs). The review primarily focuses on using hydrophyte(s)-microbe(s) associations in different CWs as an essential phytoremediation tool for sustainable management of freshwater ecosystems, ecorestoration, and prospective resource recovery, favoring a circular bioeconomy (CBE). [ABSTRACT FROM AUTHOR]

In recent times, East Kolkata Wetlands (EKW), a designated Ramsar site in the eastern part of megacity Kolkata, has been threatened by toxic heavy metal (HM) pollution. Besides being a natural wetland supporting biodiversity, EKW serves as a significant food basket for the city. For assessing the magnitude of HM pollution in this wetland, the three most cultivated food crops of EKW, namely Lagenaria siceraria (bottle gourd), Abelmoschus esculentus (ladies' fingers), and Zea mays (maize), as well as the ambient soil samples, were collected during premonsoon, monsoon, and postmonsoon for 2 consecutive years (2016 and 2017). Predominant HMs like cadmium (Cd), chromium (Cr), mercury (Hg), and lead (Pb) were analyzed in the roots and edible parts of these plants, as well as in the ambient soil to evaluate the bioaccumulation factor (BF) and translocation factor (TF) of each HM in the three vegetables. It was observed that the HM content in the food crop species followed the order Z. mays > L. siceraria > A. esculentus. HMs accumulated in all three vegetables as per the order Pb > Cd > Cr > Hg. Monsoon seems to be threatening in terms of bioaccumulation and translocation of HMs as both BF and TF were highest in this season irrespective of the plant species. Hence it demands critical monitoring of HM pollution levels in this wetland and subsequent ecorestoration through distinctive plant growth-promoting rhizobacteria (PGPR)-assisted co-cultivation of these food crops with low-metal-accumulating, deep-rooted, high-biomass-yielding, and bioenergy-producing perennial grass species for minimizing HM intake. [ABSTRACT FROM AUTHOR]

Absrtact: Oil spills have an important threat to the ecological security and human health, for example the important oil field and coastal wetland Yellow River Delta is facing the dual problems of oil pollution and salinization. Therefore, the purpose of this study was to analyze the changes of soil microbial community and physicochemical properties, including pH value, total organic carbon (TOC), total petroleum hydrocarbons (TPHs) and electrical conductivity under the combined effect of petroleum and salinization. The soil properties results showed that the petroleum addition promoted the increase of TOC from 2.31 ± 0.59 mg/kg to 7.04 ± 0.42 mg/kg (r > 0.95, P 0.9), TPHs from 9.18 ± 0.07 mg/kg to 33.09 ± 4.61 mg/kg (r > 0.9, P 0.9) significantly. At the initial stage hydrocarbons caused the increase of soil salt content and the decrease of pH. Salt addition increased soil salt from 2.46 ± 0.13 g/kg to 15.12 ± 0.21 g/kg (r > 0.8, P > 0.1, R2 > 0.95), but it had no direct effect on other soil properties. It was found that the nitrate reducing bacteria Halorhodospiraceae with potential petroleum degradation ability and the anaerobic bacteria Lactobacilliceae appeared after adding crude oil. The salt tolerant bacteria Halobacilli and the stone oil degrading bacteria Immundisolidcharacter appeared in the high salt and low salt environments respectively. The aerobic bacteria Acidimicrobiaceae, Hyphomonas and the nonoil efficient Peptoccaceae disappeared in the process of salinization and oil pollution. Lactobacilliceae can ferment carbohydrate, fatty acid or ester to produce lactic acid, acetic acid and fumaric acid to provide metabolic substrate for other microorganisms. The above results showed that sensitive microorganisms were easy to be affected by pollution to indicate soil conditions, while tolerant microorganisms could potentially use oil to achieve bioremediation. The soil properties and microbial results provided data support and theoretical basis for further understanding the pollution mechanism of oil and salinization combined stress on soil.

Mulberry (Morus spp.) of Moraceae family is regarded as a unique plant on this earth due to its broader geological distribution across the continents; ability to be cultivated in different forms; multiple uses of leaf foliage and its positive impact in environmental safety approaches such as ecorestoration of degraded lands, bioremediation of polluted sites, conservation of water, prevention of soil erosion and improvement of air quality by carbon sequestering. Mulberry is also used as a medicinal plant in improving and enhancing the life of human beings by utilizing the biologically active pharmacokinetic compounds found in leaf, stem and root parts. Further industrial exploitation of mulberry through preparation of various products in pharmaceutical, food, cosmetic and health care industries has gained the attention of industrialists. As mulberry is being exploited by sericulture, pharmaceutical, cosmetic, food and beverage industries along with its utilization in environmental safety approach; it is appropriate to call it as a most suitable plant for sustainable development. Through this review paper, all the important characteristics of mulberry were put together for considering it as an ideal plant in providing sustainable future.

Chlorophenols represent one of the most abundant families of toxic pollutants emerging from various industrial manufacturing units. The toxicity of these chloroderivatives is proportional to the number and position of chlorine atoms on the benzene ring. In the aquatic environment, these pollutants accumulate in the tissues of living organisms, primarily in fishes, inducing mortality at an early embryonic stage. Contemplating the behaviour of such xenobiotics and their prevalence in different environmental components, it is crucial to understand the methods used to remove/degrade the chlorophenol from contaminated environment. The current review describes the different treatment methods and their mechanism towards the degradation of these pollutants. Both abiotic and biotic methods are investigated for the removal of chlorophenols. Chlorophenols are either degraded through photochemical reactions in the natural environment, or microbes, the most diverse communities on earth, perform various metabolic functions to detoxify the environment. Biological treatment is a slow process because of the more complex and stable structure of pollutants. Advanced Oxidation Processes are effective in degrading such organics with enhanced rate and efficiency. Based on their ability to generate hydroxyl radicals, source of energy, catalyst type, etc., different processes such as sonication, ozonation, photocatalysis, and Fenton's process are discussed for the treatment or remediation efficiency towards the degradation of chlorophenols. The review entails both advantages and limitations of treatment methods. The study also focuses on reclamation of chlorophenol-contaminated sites. Different remediation methods are discussed to restore the degraded ecosystem back in its natural condition. • Chlorophenols are the ubiquitous compounds widely distributed in almost all the components of ecosystem. • The toxicity of CPs causes multiple organs and endocrine systems to malfunction and reduced reproductive rates. • The review evaluates the different treatment methods and their mechanism towards the degradation of these pollutants. • The study also focuses on reclamation of chlorophenol-contaminated sites and restoring the degraded ecosystem. [ABSTRACT FROM AUTHOR]

Fly ash generates as the result of coal combustion in thermoelectric power stations whereas ore mining activities produce mine waste-rock and tailings worldwide. High concentrations of metal(loid)s and organic pollutants in fly ash and mine wastes are released into soil, air, and water presenting a global threat to the surrounding environment and human health. The environmentally sound management of fly ash and mine waste–rock and tailings includes monitoring stability of the dam construction and seepage flowrate, prevention of water erosion and dust spreading, reducing the footprint of the management facilities and successful restoration/revegetation. Harsh conditions prevailing on fly ash and mine deposits are unfavorable mechanical composition and pH, high concentrations of soluble salts, lack of nitrogen and phosphorous, reduced number of microorganisms and fungus, toxic concentrations of As, Au, Ag, B, Cu, Cd, Cr, Hg, Mn, Mo, Ni, Pb, Zn, and the presence of PAHs and PCBs. The review addresses phystostabilization, phytoextraction, rhizodegradation, and phytodegradation as main phytoremediation green technologies which use plants to clean up the contaminated area to safe levels. Establishment of the self–sustaining vegetative cover on fly ash and mine deposits is crucial for recovering ecosystem health, stability, and resilience. Therefore, here we have discussed the essential role of native plants in the ecorestoration process on waste deposits. Additional emphasis is given to the evaluation of plant adaptive response to pollution stress. This review presents a current knowledge in phytomanagement of fly ash deposits, mine waste-rock and tailings. Also, it provides a new frontier in restoration physiology where physiological and biochemical tools can be used to predict plant response to stressors and success of restoration projects.

Teaching and research in Plant Ecology started in erstwhile Bombay at the then Royal Institute of Science in 1935 after Dr F.R. Bharucha joined there upon returning home after studying at the Cambridge University in U.K. and obtaining his D.Sc. from Montpellier University in France. The research covered vegetation in several parts of the Indian subcontinent, taking a new approach of phytosociological, ecological and phytogeographical aspects. With the passage of time, new generation researchers at the Institute shifted to urban ecological studies such as plants and vegetation with reference to air and water pollution, land degradation, etc. which was inevitable in the densely populated and industrial-commercial 'urbs prima' of India. Research for ecorestoration also attracted scientists who launched multidisciplinary environmental projects. [ABSTRACT FROM AUTHOR]

Among the invasive species of plants which are spreading at an alarming rate in the tropical and sub-tropical regions of the world, Prosopis (Prosopis juliflora) is arguably the most hardy and resilient. A xerophyte, which is adapted to survive and thrive in very harsh desert environments, it is a major boon for impoverished people subsisting in those environments as it provides them with badly needed shelter, reduces erosion, improves micrometeorology, and is a source of food, feed, fuel, medicines and cosmetics. Attempts made during the 19th and 20th centuries to exploit these virtues of P. juliflora has led to its introduction in many regions which had less harsh climate and better availability of soil and water than existed in the native habitat of P. juliflora. The relatively more favorable conditions resulted in P. juliflora growing and spreading much faster than it could be utilized. Soon it became a serious weed in all exotic regions where it was introduced, growing so explosively that it even enters roads and homes, driving humans out of their dwellings. The resulting damage to biodiversity is enormous. The present paper highlights the dual role of P. juliflora and itemizes the facets that make it a blessing in some contexts and a bane in other contexts. Beginning with a review of the special attributes which give invasive plants competitive advantage, the paper briefly recapitulates the systematics, origin, and spread of P. juliflora. It then dwells upon the morphology and other attributes of P. juliflora which have enabled it to invade and colonize so much of the world's landmass so rapidly. Detailed state-of-the-art is then presented on the beneficial and harmful impacts of P. juliflora. The paper concludes with a summary of assessments that have balanced the costs of destroying P. juliflora stands or utilizing them, with the possible benefits of either. [ABSTRACT FROM AUTHOR]

Fly ash (FA) is a coal combustion by-product of thermal power plants, and has been recognized as a great environmental and health hazard worldwide. The establisment of a permanent green cover on fly ash deposits is essential and can be achieved by sowing the native plant species that should be crucial for stability and resilience of an ecosystem. Improved understanding of species’ response to unfavorable properties of fly ash provides key insight into the decision about ecorestoration practice and management. Therefore, long-term research based on the assessment of the phytoremediation potential and adaptive response of Festuca rubra L. (red fescue) sown on the fly ash deposits at the thermoelectric power plant ‘Nikola Tesla-A’ in Obrenovac (Serbia) was the main concern. Field research was carried out on the passive FA lagoons (L3—the lagoons 3 years old and L2—the lagoons 11 years old) and in the Botanical Garden ́́Jevremovać́ in Belgrade (CS—control site). The physico-chemical properties of soil and fly ash were determined by using standard soil analyses. The element concentrations in soils, fly ash and plants were determined by using ICP-OES. Chlorophyll a fluorescence parameters were measured by using the Plant Stress Meter. Pigments, phenolics and malonyldialdehide contents (MDA) in leaves were measured spectrophotometrically and the total antioxidant capacity in plant leaves was determined by using DPPH free radical. Site-dependent variations were observed for all the parameters examined. FA contains alkaline pH, high electrical conductivity (EC) and low total nitrogen (N) coupled with toxic elements i.e. As and B as well as deficiency of Mn and Zn. Improvement of the physico-chemical characteristics of FA over time is reflected in the increased values of higroscopic water (HW), silt, clay, the amount of adsorbed bases (S), total adsorption capacity (T) and the reduced concentrations of total and available As, B, Cu, Zn and Mn (except available As content) indicating favorable fly ash conditions. F. rubra is an excluder plant, it retains a larger content of As, Cu, Mn and Zn in roots than in leaves and with extensive root system it can provide good fly ash stabilization, i.e. this species has a great potential in phytoremediation of FA. Furthermore, results show that F. rubra sown on the FA deposits has a high amount of MDA and reduced values of chlorophyll a fluorescence parameters (Fm, Fv, Fv/Fm, Fm/Fo), chlorophylls (Chl a , Chl a + b ) and total carotenoids (Tot Carot) indicating high oxidative stress and lower efficiency of photosynthesis. However, in spite of toxic concentrations of As and B and low content of Cu, Mn and Zn in the leaves, this species has high potential to activate adaptive mechanisms, such as increased biosynthesis of anthocyanins, phenolics, ascorbic acid and total radical scavenging activity. Taken together, F. rubra possesses high adaptive capacity to perform functional ecorestoration on fly ash deposits. These findings indicate that F. rubra can be identified as a vital element for large-scale reclamation purpose. [ABSTRACT FROM AUTHOR]

Northern boreal forests often experience forest dieback as a result of metal ore mining and smelting. The common solution is to lime the soil, which increases pH, reducing metal toxicity and encouraging recovery. In certain situations, however, such as in Flin Flon, Manitoba, Canada, liming has yielded only moderate benefits, with some locations responding well to liming and other locations not at all. In an effort to increase the effectiveness of the ecorestoration strategy, the authors investigated if these differences in liming responsiveness were linked to differences in toxicity. Toxicity of metal-impacted Flin Flon soils on the oribatid mite Oppia nitens and the collembolan Folsomia candida was assessed, with a view toward identifying the metal of concern in the area. The effects of moisture content on metal sorption, uptake, and toxicity to the invertebrates were also investigated. Toxicity tests with the invertebrates were conducted using either Flin Flon soils or artificial soils with moisture content adjusted to 30%, 45%, 60%, or 75% of the maximum water-holding capacity of the soil samples. The Relative to Cd Toxicity Model identified Zn as the metal of concern in the area, and this was confirmed using validation tests with field contaminated soils. Furthermore, increasing the moisture content in soils increased the amount of mobile Zn available for uptake with the ion exchange resin. Survival and reproduction of both invertebrates were reduced under Zn exposure as moisture level increased. Thus, moisture-collecting landforms, which are often also associated with high Zn concentrations at Flin Flon, have, as a result, higher Zn toxicity to the soil ecosystem because of increases in soil moisture. Environ Toxicol Chem 2015;34:600-607. © 2014 SETAC [ABSTRACT FROM AUTHOR]

Present study was carried out in an ecorestored rock phosphate mine at Maldeota area of the Dehradun, Uttarakhand, India where ecorestoration measures were undertaken in 15 hectare mine soil area during the year 1982 by Forest Research Institute in collaboration with Pyrites Phosphate Chemical Limited (PPCL). The objective was to understand chemical changes, which took place in an age series of 23, 22, 21 and 20 years old mine restored sites rock phosphate mine and an adjoining natural forest was also studied for comparison of soil chemical properties. All the data was analyzed by using the Statistical Package for Social Science Program for Windows version 15.0. Multiple comparison and two way analysis of variance (ANOVA) procedures were used to compare differences among samples. The Least Significant Difference (LSD) test was performed to determine the significant differences among sample means at p < 0.05. Increase in all the nutrients has been observed during the study period. A significant difference (p < 0.05, p < 0.01, p < 0.001) has been recorded on an average in the amount of nutrient (kg ha-1). As the mining of minerals leaves behind the overburden dumps and infertile soil, the restoration efforts help in regaining the biodiversity and ecosystem services. [ABSTRACT FROM AUTHOR]

Fly ash dump has been noticed as one of the hazardous dumpsites on the earth, which pollutes our environment. Therefore, an affordable and effective approach for the restoration of fly ash dumps is urgently required worldwide. In this direction, to find out potential plant species through the assessment of naturally colonized vegetation is a basic criterion of ecological restoration. With the above vision, the present study was performed to identify potential colonizer plants of fly ash dumps for ecological restoration. The intensive field studies were made during 2019–2020 to gather naturally occurring plants from fly ash disposal area of Koradi Thermal Power Plant, Nagpur, Maharashtra, India. Therefore, naturally colonizing plants were assessed on the basis of their dominance, ability of improving the rhizospheric FA, and ecological significance for their ecorestoration potential. Acacia nilotica L., Acmella oleracea L., Bacopa monnieri L., Cynodon dactylon (L.) Pers., Cyperus rotundus L., Dactyloctenium aegyptium L., Digitaria sanguinalis L., Trianthema portulacastrum L., Typha latifolia L. and Portulaca oleracea L. were recognized as potential plants for ecological restoration of FA dumps. Hence, the characteristics of above identified potential plant species can be used in ecological restoration of newly FA disposal areas. • Natural plant communities were assessed to have insights on ecorestoration potential. • Eco-restoration of fly ash dump via naturally colonized plant species is limited. • Both sites are not similar in features due to change in colonizing species pattern. • Restoration programs on fly ash dump should base on natural colonizer plant species. • Colonizing plant species over fly ash dumps have ecological resilience that governs the response to hash conditions. [ABSTRACT FROM AUTHOR]

The mangrove forest of Puduvyppu located on the west cost of India (District Ernakulam, Kerala) was investigated with an objective to characterize the species distribution along the sea-land interface (from the seashore to 1200 m inwards). The phytosociological analysis showed a marked zonation pattern of species diversity and their distribution in this forest. The species diversity decreased from the sea-land interface towards the land whereas, the density and basal area of the predominant species increased. A phenomenon called "tidal sorting" caused zonal distribution of species and higher nutrient contents in the landward site compared with the seaward sites resulted in higher species density and basal area. Thus, the variations in the edaphic attributes and site specificity of the colonizing species is a unique character of this ecosystem. The ecorestoration activities at this site should, therefore, consider species distribution attributes, especially in deciding the most appropriate species for afforestation at a particular site; for example, Sonneratia caseolaris on the seaward side and Bruguiera cylindrica and Avicennia officinalis on the landward side. [ABSTRACT FROM AUTHOR]

Shows the role played by mathematical modeling in understanding and managing forest ecosystems. Demonstration of how mathematical analysis of a simplified forest growth model predicts properties such as the time required to recover from perturbation, and the response to various levels of harvesting intensity; Aid for ecorestoration and ecosystem management efforts.

Oil spills have an important threat to the ecological security and human health, for example the important oil field and coastal wetland Yellow River Delta is facing the dual problems of oil pollution and salinization. Therefore, the purpose of this study was to analyze the changes of soil microbial community and physicochemical properties, including pH value, total organic carbon (TOC), total petroleum hydrocarbons (TPHs) and electrical conductivity under the combined effect of petroleum and salinization. The soil properties results showed that the petroleum addition promoted the increase of TOC from 2.31 ± 0.59 mg/kg to 7.04 ± 0.42 mg/kg (r > 0.95, P < 0.1, R2 > 0.9), TPHs from 9.18 ± 0.07 mg/kg to 33.09 ± 4.61 mg/kg (r > 0.9, P < 0.05, R2 > 0.9) significantly. At the initial stage hydrocarbons caused the increase of soil salt content and the decrease of pH. Salt addition increased soil salt from 2.46 ± 0.13 g/kg to 15.12 ± 0.21 g/kg (r > 0.8, P > 0.1, R2 > 0.95), but it had no direct effect on other soil properties. It was found that the nitrate reducing bacteria Halorhodospiraceae with potential petroleum degradation ability and the anaerobic bacteria Lactobacilliceae appeared after adding crude oil. The salt tolerant bacteria Halobacilli and the stone oil degrading bacteria Immundisolidcharacter appeared in the high salt and low salt environments respectively. The aerobic bacteria Acidimicrobiaceae, Hyphomonas and the nonoil efficient Peptoccaceae disappeared in the process of salinization and oil pollution. Lactobacilliceae can ferment carbohydrate, fatty acid or ester to produce lactic acid, acetic acid and fumaric acid to provide metabolic substrate for other microorganisms. The above results showed that sensitive microorganisms were easy to be affected by pollution to indicate soil conditions, while tolerant microorganisms could potentially use oil to achieve bioremediation. The soil properties and microbial results provided data support and theoretical basis for further understanding the pollution mechanism of oil and salinization combined stress on soil. • Petroleum had direct and continuous impacts on soil TOC (r > 0.95) and TPHs (r > 0.9), but not salinity and pH. • The soil in Yellow River Delta (YRD) alleviated the effect of salt addition, which only affected salinity (r > 0.8) slightly. • The anaerobic petroleum degradation microorganisms like Lactobacillaceae , Halorhodospiraceae flourished with other sensitive microbes decreasing or fading. [ABSTRACT FROM AUTHOR]

• Bamboo stands out as an ideal choice for eco-rejuvenation of rural wasteland. • Eco-rejuvenation technology accelerates the natural succession processes. • Soil fertility and productivity in degraded land can enhance rural socio-economy. Eco-restoration is a technique for rejuvenation of degraded ecosystem to their near original state. It also helps to control soil erosion, develop microbial ecology, enhance biomass production and socio-economic development. The present study was focused on a new approach called Eco-Rejuvenation Technology (ERT) for reclamation and ecological/biodiversity restoration of degraded land. To demonstrate this technology, plantation of seedlings of 5 different bamboo species (Bambusa balcooa Roxb. , Bambusa vulgaris var. vittata (Schrad. ex Wendl) (Green), Bambusa vulgaris var. striata (Yellow), Bambusa nutans Wall. ex Munro and Dendrocalamus asper (Schult.f.) Backer ex Heyne) was carried out in a village community degraded land located in Central India where organic amendments, such as press mud, farmyard manure and bio-fertilizers were apllied. This study showed how ERT benefited the growth of bamboo (viz., increased height, diameter, number of culms) and further explained how it could help in increasing soil biomass and carbon sequestration capacity over a period of one year. The results reflected that the success of a rural wasteland restoration program depends on community participation and socio-economic factors as well as ecological improvement. In this study, the soil organic carbon (SOC) was restored to nearly 1% within a year. It clearly suggested that ERT is a potential tool for sustainable rural development through native biodiversity development on degraded land. [ABSTRACT FROM AUTHOR]