An experimental study of the rhizosphere effect on phytoremediation of petroleum polluted soil was carried out with three species of grasses, namely Pannicum, Eleusine indica （L.） Gaerth, and Tall Fescue. After a pe...An experimental study of the rhizosphere effect on phytoremediation of petroleum polluted soil was carried out with three species of grasses, namely Pannicum, Eleusine indica （L.） Gaerth, and Tall Fescue. After a period of 150 days, this pot experiment showed that the rhizosphere of these three species accelerated the degradation of petroleum hydrocarbons to different extents. The results showed that the number of microorganisms in the rhizosphere increased by three orders of magnitude. The induction of the plant rhizosphere and the coercion influence of petroleum changed the species and activity of microorganisms. The degradation of petroleum hydrocarbons in the rhizosphere was 3-4 times that in unplanted soil. The dehydrogenase activity in the rhizosphere was 1.61-2.20 times that in unplanted soil, but the catalase activity was 0.90-0.93 times that in unplanted soil, and soil moisture content increased by 5% compared with the unplanted soil.展开更多
Plants are capable of reducing environmental pollutions through uptaking contaminants in their tissues. In the study site, twenty one-year-old leaves and shoots as well as twenty soil samples were sampled and analyzed...Plants are capable of reducing environmental pollutions through uptaking contaminants in their tissues. In the study site, twenty one-year-old leaves and shoots as well as twenty soil samples were sampled and analyzed by Inductively Coupled Plasma （ICP）. We investigated the uptaking ability of lead （Pb） and cadmium （Cd） by the leaves and shoots of Platanus orientalis, Robinia pseudoacacia and Fraxinus rotundifolia in Karaj city, the western Tehran, Iran. We also evaluated the total metal accumulation capacity by using metal accumulation index （MAI）. Results indicated that there was no significant difference in uptaking contents of Cd and Pb in the leaves among the trees. However accumulation of Cd in shoots of F. rotundifolia and R. pseudoacacia was significantly higher than that of P. orientalis. The accumulation of Pb in shoots of R. pseudoacacia was significantly higher than the other species. The amount of Pb in the soil of the study area was significantly higher than Cd. Concentrations of Cd and Pb in leaves of the three species are in the ranges of 2.4 2.7 mg Kg-1 and 7.1 14.4 mg Kg-1 , respectively. R. pseudoacacia had the highest MAI value for leaves （2.21） and F. rotundifolia had the highest MAI value for shoots （2.4）.展开更多
Mining alters the natural landscape and discharges large volumes of wastes that pose serious pollution hazards to the environment, to human health and to agriculture. As a result, the recent 2 decades have witnessed a...Mining alters the natural landscape and discharges large volumes of wastes that pose serious pollution hazards to the environment, to human health and to agriculture. As a result, the recent 2 decades have witnessed a global surge in research on post-mining landscape restoration, yielding a suite of techniques including physical, chemical, biological(also known as phytoremediation) and combinations. Despite the long history of mining in Africa, no systematic review has summarized advances in restoration research and practices after mining disturbance. Thus, the aim of this review was to document the state-of-knowledge and identify gaps in restoration of postmining landscape in Africa through literature review. We found that:(1) there has been substantial progress in identifying species suitable for phytoremediation;(2) few studies evaluated the feasibility of organic amendments to promote autochthonous colonization of mine wastelands or growth of planted species; and(3) restoration of limestone quarries in Kenya, sand mining tailings in South Africa,and gold mine wasteland in Ghana are successful cases of large-scale post-mining restoration practices in Africa.However, the pace of post-mining landscape restoration research and practice in Africa is sluggish compared to other parts of the global south. We recommend:(1)mainstreaming the restoration of mine wastelands in national research strategies and increased development planning to make the mining sector ‘‘Green'';(2) inventory of the number, area, and current status of abandoned mine lands;(3) expanding the pool of candidate species for phytostabilization;(4) further evaluating the phytostabilization potential of organic amendments, e.g., biochar;(5)assessing the impacts of mining on regional biodiversity.展开更多
We investigated wood anatomical changes due to uptake and accumulation of cadmium and lead from contaminated soils in Acer velutinum Boiss seedlings. Two-year old seedlings were exposed for 180 days to soil concentrat...We investigated wood anatomical changes due to uptake and accumulation of cadmium and lead from contaminated soils in Acer velutinum Boiss seedlings. Two-year old seedlings were exposed for 180 days to soil concentrations with varying cadmium and lead concentra- tions. We measured three wood anatomical traits, average vessel area （gm2）, vessel number per square millimetre, and vessel lumen area per- centage （%）. For assessing the cadmium and lead accumulation, we measured the concentrations in the soil, leaf, stem, and root. Average vessel area and vessel lumen area percentage were similar （p〉0.05） in control and treated seedlings. Vessel number per square millimetre showed a decreasing trend from pith to bark in control and treated seed- lings, and the trend was more pronounced in treated seedlings. We con- clude that vessel number per square millimetre in A. velutinum is influ- enced by soil contamination. A. velutinum Boiss is not a suitable species for remediation of soils contaminated by cadmium and lead but it can be used as an indicator of the soil lead contamination, because lead concentrations in seedlings increased with increasing amount of lead in the soil.展开更多
It is important to understand seasonal heavy metal accumulation in different parts of plants in order to develop the best phytoremediation practices for con- taminated soils. For this purpose we exposed, 1 year old A....It is important to understand seasonal heavy metal accumulation in different parts of plants in order to develop the best phytoremediation practices for con- taminated soils. For this purpose we exposed, 1 year old A. victoriae seedlings to ZnSO4 in 4 different concentrations： 0, 50, 250 and 500 mg Zn L-1 for 45 days over two growing seasons. Subsequently, bioaccumulation of Zn in different plant tissues （roots, shoots and leafs） was assessed by Atomic Absorption Spectroscopy （AAS） for two peri- ods. In addition, various growth attributes （dry biomass, shoot and root lengths, plant appearance） and functional traits （leaf area, chlorophyll a, b and total） were measured. The accumulation of Zn was influenced by the Zn con- centration in the growth medium and the number of growing seasons. The amounts of Zn concentrated in the root tissues might indicate A. victoriae as a good option for phytostabilization of soils contaminated by Zn. We rec- ommend that if A. victoriae is used for phytoextraction purposes, then it should be harvested at the end of the first growing season （fall） because at this time the concentra- tions of Zn in the above-ground parts will be maximal.展开更多
The development of the mining industry has led to the appearance in many parts of the world of vast technogenic territories from which toxic heavy metals enter the environment and food chains.Physical,chemical,and bio...The development of the mining industry has led to the appearance in many parts of the world of vast technogenic territories from which toxic heavy metals enter the environment and food chains.Physical,chemical,and biological methods of cleaning industrial land due to technological complexity and hi gh cost are relatively little used on a large scale.Natural forest overgrowth of mining sites and the removal of heavy metals by woody plants can be an effective form of recovery.Therefore,the study of this process is of significant scientific and practical interest.The analysis of the annual growth in height and width of the annual rings of the stem of Scots pine(Pinus sylvestris L.) in 2004-2019 was made on the territory of the Uchalinsky mining and processing plant(South Ural,Russia) contaminated with heavy metals.Relatively hi gh concentrations of copper and zinc were found in soils,roots,bark,young shoots,comparable to exceeding the maximum allowable concentrations.Despite the spatial uniformity of the heavy metal content in the stands,the tree samples significantly differed in terms of annual growth.Results suggest that the lack of nutrients and not stress from exposure to heavy metals is the main reason for relatively low growth rates on slopes of industrial wastes.It was confirmed by studying the annual growth in height of the undergrowth in habitats with different soil cover conservation.The data prove the relatively high potential of Scots pine for the natural recovery of industrial lands polluted with heavy metals by mining enterprises.展开更多
基金This work was supported by the National Natural Science Foundation of China under grant No.40672211.
文摘An experimental study of the rhizosphere effect on phytoremediation of petroleum polluted soil was carried out with three species of grasses, namely Pannicum, Eleusine indica （L.） Gaerth, and Tall Fescue. After a period of 150 days, this pot experiment showed that the rhizosphere of these three species accelerated the degradation of petroleum hydrocarbons to different extents. The results showed that the number of microorganisms in the rhizosphere increased by three orders of magnitude. The induction of the plant rhizosphere and the coercion influence of petroleum changed the species and activity of microorganisms. The degradation of petroleum hydrocarbons in the rhizosphere was 3-4 times that in unplanted soil. The dehydrogenase activity in the rhizosphere was 1.61-2.20 times that in unplanted soil, but the catalase activity was 0.90-0.93 times that in unplanted soil, and soil moisture content increased by 5% compared with the unplanted soil.
基金The project was financially supported by parks organization of Karaj municipality
文摘Plants are capable of reducing environmental pollutions through uptaking contaminants in their tissues. In the study site, twenty one-year-old leaves and shoots as well as twenty soil samples were sampled and analyzed by Inductively Coupled Plasma （ICP）. We investigated the uptaking ability of lead （Pb） and cadmium （Cd） by the leaves and shoots of Platanus orientalis, Robinia pseudoacacia and Fraxinus rotundifolia in Karaj city, the western Tehran, Iran. We also evaluated the total metal accumulation capacity by using metal accumulation index （MAI）. Results indicated that there was no significant difference in uptaking contents of Cd and Pb in the leaves among the trees. However accumulation of Cd in shoots of F. rotundifolia and R. pseudoacacia was significantly higher than that of P. orientalis. The accumulation of Pb in shoots of R. pseudoacacia was significantly higher than the other species. The amount of Pb in the soil of the study area was significantly higher than Cd. Concentrations of Cd and Pb in leaves of the three species are in the ranges of 2.4 2.7 mg Kg-1 and 7.1 14.4 mg Kg-1 , respectively. R. pseudoacacia had the highest MAI value for leaves （2.21） and F. rotundifolia had the highest MAI value for shoots （2.4）.
基金the Swedish Science Council(Vetenskapsradet,C0626501 and D0650301)
文摘Mining alters the natural landscape and discharges large volumes of wastes that pose serious pollution hazards to the environment, to human health and to agriculture. As a result, the recent 2 decades have witnessed a global surge in research on post-mining landscape restoration, yielding a suite of techniques including physical, chemical, biological(also known as phytoremediation) and combinations. Despite the long history of mining in Africa, no systematic review has summarized advances in restoration research and practices after mining disturbance. Thus, the aim of this review was to document the state-of-knowledge and identify gaps in restoration of postmining landscape in Africa through literature review. We found that:(1) there has been substantial progress in identifying species suitable for phytoremediation;(2) few studies evaluated the feasibility of organic amendments to promote autochthonous colonization of mine wastelands or growth of planted species; and(3) restoration of limestone quarries in Kenya, sand mining tailings in South Africa,and gold mine wasteland in Ghana are successful cases of large-scale post-mining restoration practices in Africa.However, the pace of post-mining landscape restoration research and practice in Africa is sluggish compared to other parts of the global south. We recommend:(1)mainstreaming the restoration of mine wastelands in national research strategies and increased development planning to make the mining sector ‘‘Green'';(2) inventory of the number, area, and current status of abandoned mine lands;(3) expanding the pool of candidate species for phytostabilization;(4) further evaluating the phytostabilization potential of organic amendments, e.g., biochar;(5)assessing the impacts of mining on regional biodiversity.
文摘We investigated wood anatomical changes due to uptake and accumulation of cadmium and lead from contaminated soils in Acer velutinum Boiss seedlings. Two-year old seedlings were exposed for 180 days to soil concentrations with varying cadmium and lead concentra- tions. We measured three wood anatomical traits, average vessel area （gm2）, vessel number per square millimetre, and vessel lumen area per- centage （%）. For assessing the cadmium and lead accumulation, we measured the concentrations in the soil, leaf, stem, and root. Average vessel area and vessel lumen area percentage were similar （p〉0.05） in control and treated seedlings. Vessel number per square millimetre showed a decreasing trend from pith to bark in control and treated seed- lings, and the trend was more pronounced in treated seedlings. We con- clude that vessel number per square millimetre in A. velutinum is influ- enced by soil contamination. A. velutinum Boiss is not a suitable species for remediation of soils contaminated by cadmium and lead but it can be used as an indicator of the soil lead contamination, because lead concentrations in seedlings increased with increasing amount of lead in the soil.
文摘It is important to understand seasonal heavy metal accumulation in different parts of plants in order to develop the best phytoremediation practices for con- taminated soils. For this purpose we exposed, 1 year old A. victoriae seedlings to ZnSO4 in 4 different concentrations： 0, 50, 250 and 500 mg Zn L-1 for 45 days over two growing seasons. Subsequently, bioaccumulation of Zn in different plant tissues （roots, shoots and leafs） was assessed by Atomic Absorption Spectroscopy （AAS） for two peri- ods. In addition, various growth attributes （dry biomass, shoot and root lengths, plant appearance） and functional traits （leaf area, chlorophyll a, b and total） were measured. The accumulation of Zn was influenced by the Zn con- centration in the growth medium and the number of growing seasons. The amounts of Zn concentrated in the root tissues might indicate A. victoriae as a good option for phytostabilization of soils contaminated by Zn. We rec- ommend that if A. victoriae is used for phytoextraction purposes, then it should be harvested at the end of the first growing season （fall） because at this time the concentra- tions of Zn in the above-ground parts will be maximal.
文摘The development of the mining industry has led to the appearance in many parts of the world of vast technogenic territories from which toxic heavy metals enter the environment and food chains.Physical,chemical,and biological methods of cleaning industrial land due to technological complexity and hi gh cost are relatively little used on a large scale.Natural forest overgrowth of mining sites and the removal of heavy metals by woody plants can be an effective form of recovery.Therefore,the study of this process is of significant scientific and practical interest.The analysis of the annual growth in height and width of the annual rings of the stem of Scots pine(Pinus sylvestris L.) in 2004-2019 was made on the territory of the Uchalinsky mining and processing plant(South Ural,Russia) contaminated with heavy metals.Relatively hi gh concentrations of copper and zinc were found in soils,roots,bark,young shoots,comparable to exceeding the maximum allowable concentrations.Despite the spatial uniformity of the heavy metal content in the stands,the tree samples significantly differed in terms of annual growth.Results suggest that the lack of nutrients and not stress from exposure to heavy metals is the main reason for relatively low growth rates on slopes of industrial wastes.It was confirmed by studying the annual growth in height of the undergrowth in habitats with different soil cover conservation.The data prove the relatively high potential of Scots pine for the natural recovery of industrial lands polluted with heavy metals by mining enterprises.
