甘蔗修复重金属污染土壤的研究

植物修复土壤重金属污染作为一种低成本和环境友好技术得到了广泛的关注,应用大生物量植物修复污染土壤前景广阔。甘蔗拥有良好的环境适应性、发达的根系、较高的生物量,对重金属有较强的耐受性和积累性,还可循环综合利用。因此,综合考虑资源、环境与经济的可持续发展,将甘蔗应用于植物修复土壤重金属污染是可行的。     

生物法除锰技术研究综述

对生物法除锰原理和技术,以及除锰微生物和锰超富集植物进行了综述,并分析了生物除锰技术存在的问题及发展方向。重点介绍了生物滤池法、人工湿地法和植物修复等生物除锰技术的应用研究进展。     

化工污染场地植物修复研究

[目的]研究植物对复合污染土壤的修复效果。[方法]采取模拟试验,进行 Pb-Cd复合污染、PAHs污染和 Pb-Cd-PAHs复合污染土壤修复植物的筛选,通过种植黑麦草,调控生物有效性影响因素对污染场地土壤进行修复。[结果]种植黑麦草70 d后污染土壤有效态 Pb的含量为375.26 mg/kg,90 d后土壤有效态 Cd含量为4.9 mg/kg,110 d后土壤有效态 B[a]P的含量为0.60 mg/kg,都低于土壤限值,能达到修复效果。[结论]黑麦草是适于复合污染土壤修复的植物。     

杨树林地处理生活污水生态效应

为了研究不同污水水力负荷对不同杨树品种人工林的影响,选择了‘I-72’、‘欧美107’、‘中林2001’与‘中林46’四个杨树品种,分别按照3、6、9、12、15 cm·周~(-1)5个水力负荷进行污水处理;测定试验期间各品种地上部分生长量、凋落物量与污染物积累量。结果表明:3~9 cm·周~(-1)水力负荷增加了‘I-72’、‘中林2001’、‘欧美107’的生长量、凋落物量与污染物积累量;水力负荷大于9 cm·周~(-1)时,这3个杨树品种生长量、凋落物量与污染物积累量随着水力负荷增加而降低。在这3个品种中,‘中林2001’年生长量与污染物积累量最大,‘欧美107’中等,‘I-72’最低。从杨树生长量与污染物积累量来看,‘中林2001’最适合作为污水处理的植物材料,其次是‘欧美107’、I-72杨,污水处理的适宜水力负荷为6~9 cm·周~(-1),‘中林46’不适合用于污水处理。     

Enhanced phytoremediation of multi-metal contaminated soils by interspecific fusion between the protoplasts of endophytic Mucor sp. CBRF59 and Fusarium sp. CBRF14

The aim of this study was to isolate protoplasts from different metal resistant endophytic fungi and to carry out interspecific fusion of protoplasts to enhance bioremediation of contaminated soils. Three stable fusants (F1, F2, and F3) with resistance to Cd and Zn were constructed by interspecific fusion between inactivated protoplasts from Cd-resistant endophytic Mucor sp. CBRF59 and Zn-resistant endophytic Fusarium sp. CBRF14. The fusants increased concentrations of water soluble Cd, Pb, and Zn in soils, promoted rape growth, increased metal concentrations in the rape, elevated the extractable metal amount, and increased metal translocation from roots to shoots in soils containing single metals or multi-metals. Especially, the fusants showed much higher extraction efficacy than the parents in soils contaminated by multi-metals. The results indicated that protoplast fusion should be a feasible and efficient fungal method, which could be utilized to construct stable fusants by combining the genetic traits of parents for bioremediation of contaminated soils by multi-metals.     

Enhancement of arbuscular mycorrhizal fungus (Glomus versiforme) on the growth and Cd uptake by Cd-hyperaccumulator Solanum nigrum

Arbuscular mycorrhizal fungus (AMF) can enhance plant growth and resistance to toxicity produced by heavy metals (HMs), affect the bioavailability of HMs in soil and the uptake of HMs by plants, and thus has been emerged as the most prominent symbiotic fungus for contribution to phytoremediation. A greenhouse pot experiment was conducted to assess the effect of Glomus versiforme BGC GD01C (Gv) on the growth and Cd accumulation of Cd-hyperaccumulator Solanum nigrum in different Cd-added soils (0, 25, 50, 100 mg Cd kg⁻¹ soil). Mycorrhizal colonization rates were generally high (from 71% to 82%) in Gv-inoculated treatments at all Cd levels. Gv colonization enhanced soil acid phosphatase activity, and hence elevated P acquisition and growth of S. nigrum at all Cd levels. Moreover, the presence of Gv significantly increased DTPA-extractable (phytoavailable) Cd concentrations in 25 and 50 mg Cd kg⁻¹ soils, but did not affect phytoavailable Cd in 100 mg Cd kg⁻¹ soil. Similarly, inoculation with Gv significantly increased Cd concentrations of S. nigrum in 25 and 50 mg Cd kg⁻¹ soils, but decreased Cd concentrations of the plants in 100 mg Cd kg⁻¹ soil. Overall, inoculation with Gv greatly improved the total Cd uptakes in all plant tissues at all Cd levels. The present results indicated that S. nigrum associated with Gv effectively improved the Cd uptake by plant and would be a new strategy in microbe-assisted phytoremediation for Cd-contaminated soils.     

Effect of Nitrogen Fertilizers on Zinc Accumulation in Fescue

Abstract

This research evaluated effects of nitrogen fertilizers on availability of zinc (Zn) in soils. Two slit loams of the Hadley series (Typic Udifluvents) were used. Zinc sulfate was mixed with the soils to give Zn at 125, 250, 500, or 1,000 mg/kg and incubated for 14 days. Fertilizers (compost, cow manure, urea) were mixed with the soils to supply N at 200 mg/kg. Fourteen days after the fertilizers were mixed with the Zn‐treated soils, soil samples were taken for analysis of plant‐available Zn by extraction with Morgan's solution or water. After the soil samples were taken, fescue (Festuca arundinacea Schreb.) seeds were placed into pots to assess germination, growth, and Zn accumulation. Higher concentrations of Morgan's extractable Zn were detected in soils treated with compost (201 mg/kg) than with calcium nitrate (179 mg/kg), manure (153 mg/kg), or urea (152 mg/kg). However, with water extraction, higher Zn concentrations were detected in soils treated with calcium nitrate (36 mg/kg) with the lowest concentrations being extracted from soils treated with urea (8 mg/kg). Extraction of Zn by Morgan's solution or water increased as the soil‐Zn levels increased. Fescue germinated and grew at all of the soil‐Zn levels. The highest concentration of Zn occurred in plants grown in soils amended with calcium nitrate or urea, and the lowest concentration was in plants grown in soils amended with compost or manure. Fescue grown in soils amended with urea had the largest dry mass, and plants grown with compost or manure had the smallest. Zinc concentration and accumulation for fescue shoots increased as the soil‐Zn levels increased. These results suggest that accumulation of Zn in fescue can be enhanced by selection of nitrogen‐containing fertilizers that affect the solubility of Zn in soils.     

修复植物香薷堆肥对缺铜土壤上冬小麦生长和铜吸收的初步研究

通过堆积腐解处理生长在Cu污染土壤上的修复植物-海州香薷,将其研制成堆肥,作为基肥施用于缺Cu土壤,以矫正作物缺Cu症状。盆栽试验研究了这种堆肥对冬小麦(TriticumaestivumL.)生长和Cu吸收的影响。结果表明,施用海州香薷堆肥可显著提高生长在缺Cu土壤上的小麦的株高、生物量和籽实千粒重。与CK相比,千粒重可提高58.9%,籽实产量提高近1倍;而在这种缺Cu土壤上单纯施加N、P、K化肥,反而降低小麦生物量和籽实千粒重。可见,将Cu污染土壤上生长的修复植物海州香薷制成堆肥,施用于缺Cu土壤是一种可实现修复植物资源化的有效途径。     

Wood anatomical changes due to uptake of cadmium and lead from contaminated soils in Acer velutinum seedlings

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 concentrations. We measured three wood anatomical traits, average vessel area(μm2), vessel number per square millimetre, and vessel lumen area percentage (%). 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) incontrol and treated seedlings. Vessel number per square millimetre showed a decreasing trend from pith to bark in control and treated seedlings, and the trend was more pronounced in treated seedlings. We conclude that vessel number per square millimetre in A. velutinum is influenced by soil contamination. A. velutinum Boiss is not a suitable species for remediation of soils contaminated by cadmium and lead but it can beused as an indicator of the soil lead contamination, because lead concentrations in seedlings increased with increasing amount of lead in the soil.     

土壤重金属污染及植物修复技术研究

从重金属的概念及污染土壤的特点出发,概括了我国土壤重金属污染的现状及危害,论述了重金属污染土壤的植物修复技术原理、类型、研究现状及优缺点,并对植物修复技术的研究趋势及在我国的发展前景进行了展望。