A critical review on the phytoremediation of heavy metals from environment: Performance and challenges

Qi-zhong

et al. 2022

Forests

Phytoremediation is an important solution to heavy metal pollution in soil. However, the impact of plants on microbial communities in contaminated soil also requires attention. Community-level physiological profiling (CLPP) based on the Biolog™ EcoPlate and high-throughput sequencing were used to study the soil microbial community in this article. The rhizosphere and bulk soil samples of six native species were collected from the iron mine tailings on Jiulong Mountain, Jiangxi Province. According to the average well color development (AWCD), all plants improved the activity and diversity of the contaminated soil microbial community to varying degrees. Cunninghamia lanceolate is considered to have good effects and led to the appearance of Cunninghamia lanceolata > Zelkova schneideriana > Toona ciliata > Alnus cremastogyne > Cyclobalanopsis myrsinifolia > Pinus elliottii. The Shannon–Wiener diversity index and principal component analysis (PCA) show that the evenness and dominance of soil microbial communities of several plants are structurally similar to those of uncontaminated soil (UNS). The results of high-throughput sequencing indicated that the bacterial community diversity of C. lanceolata, A. cremastogyne, and P. elliottii is similar to UNS, while fungal community diversity is different from UNS. C. lanceolata has a better effect on soil nutrients, C. myrsinifolia and P. elliottii may have a better effect on decreasing the Cu content. The objective of this study was to assess the influence of native plants on microbial communities in soils and the soil remediation capacity. Mortierellomycota was the key species for native plants to regulate Cu and microbial community functions. Native plants have decisive influence on microbial community diversity.

Section: Effects Of Native Plants On Soil Chemical Characteristicsmentioning

confidence: 99%

Effects of Different Native Plants on Soil Remediation and Microbial Diversity in Jiulong Iron Tailings Area, Jiangxi

Qi-zhong

et al. 2022

Forests

“…Phytoremediation is recognized as an eco-friendly, green, and sustainable approach to soil remediation, but it also faces important performance and efficiency issues. For most heavy metals, remediation of contaminated soils by phytoremediation alone spans decades [50,51]. That is, agricultural production needs to be interrupted for a long period, which is also the main factor restricting farmers' choices of phytoremediation.…”

Section: Farmers' Technology Preferencementioning

confidence: 99%

The Willingness and Technology Preferences of Farmers and Their Influencing Factors for Soil Remediation

Yan

Yang

2022

Land

Farmers are one of the major uncertainty factors in remediation of contamination farmland. Based on the face-to-face questionnaire survey data of 553 farmers in 4 heavy metal-contaminated agricultural soil remediation projects in China, this study used methods, such as structural equation modeling and random forest to explore farmers’ willingness to remediate, technology preference, and their key influencing factors for the first time. The results showed that farmers were willing to remediate contaminated soil and preferred phytoremediation, with 82.8% choosing phytoremediation, 12.5% choosing passivation, and 4.7% believing that the soil did not need to be remediated. In terms of willingness to remediate, the perceived benefits from participation in current remediation projects directly contributed to future willingness, with participation status (total impact coefficient 0.86) and perceived benefits (impact coefficient 0.49) being the main factors positively influencing farmers’ willingness. With regard to technology preference, technical characteristics (soil quality, 17.1%; secondary contamination, 16.8%; and remediation period, 11.5%) were the main influencing factors. The sustainability of passivation effect and the possible secondary contamination restrict the promotion of passivation, whereas the cessation of agricultural production during the long remediation period restricts the promotion of phytoremediation. It is recommended to increase farmers’ willingness to remediate by improving their perceived benefits and continuously overcoming the technical barriers by: (i) developing efficient and green passivators; and (ii) improving the efficiency of phytoremediation as well as intercropping or rotating cash crops while remediating. The results have important reference value for soil remediation in agricultural countries with small arable land per capita.

IOP Conf. Ser.: Earth Environ. Sci.

“…Many factors, including soil properties (nutrient, pH, moisture, oxygen content, microorganism, organic matter), plant species, climate conditions (temperature, rainfall), as well as additives, can influence plant biomass and bioavailability to promote or limit phytoremediation efficiency. [36] Plants selection is the key to achieve the good results in phytoremediation projects. The most common species for phytoremediation (not wetlands) in Sweden are Willow.…”

Section: Factors To Influence the Phytoremediation Efficiencymentioning

confidence: 99%

Phytoremediation development in Sweden

Chang

Hogland²

2022

The contaminated air, water and soil have been major environmental issues during the last decades in Sweden. The phytoremediation technologies with ecological and economic benefits may help to alleviate those problems, especially related to heavy metal and organic pollutants. There is paucity of literatures on comprehensive understanding of phytoremediation technology development in Sweden. The Environmental Science and Engineering Group (ESEG) at Linnaeus University has been working on the relevant topics for decades and achieved some important findings. This study aimed at providing a systematic insight on the phytoremediation development in Sweden through literature reviews as well as summarizing the doctoral theses presented by ESEG. Herein suggestions and recommendations for phytoremediation development are given, especially those projects and research in Sweden and other countries with similar climate situation, which can benefit the works for site managers and engineers as well as ecologists and biochemists. The study presents useful findings: 1) The majority of phytoremediation research in Sweden is focused on wetlands. Some are working on soil remediation, and very few on air purification. Submerged plant species in wetlands have been shown to be more effective at removing heavy metals than free-floating and terrestrial plants. Willow is the most popular species used in soil remediation, and there are many different clones. There are some other potential plants for phytoremediation, including Poplar, Silver Birch, Alfalfa, Spinach, Fireweed, Reed Canary grass, Scots pine, Rapeseed, etc. 2) Composting, bacteria, and iodides are examples of additions that can help improve phytoremediation efficiency. 3) Both biomass yields and contaminants accumulation concentration in plant must be considered when evaluating phytoremediation efficiency. 4) The efficacy of the phytoremediation function will be influenced by factors such as plant selection, climate situation, additions of substrate, soil properties, etc. Furthermore, the concentration of contaminants varies between plants as well as between different parts of the plant. 5) Management and maintenance are essential for a successful phytoremediation operation. It is critical to protect plants against disease, fungi, insects, pests and so on.