The effects of two arbuscular mycorrhizal fungi ( Glomus versiforme and Paraglomus occultum ) on size distribution of soil water-stable aggregate and aggregate stability,glomalin-related soil protein (GRSP),and carbohydrates of white clover ( Trifolium repens ) were analyzed. Root mycorrhizal infection ranged from 35% to 75% after 85 days of mycorrhizal inoculation. The inoculated treatments significantly increased shoot,root,and total dry biomass and chlorophyll content. White clover was more dependent on P. occultum than on G. mosseae . The treatments inoculated with arbuscular mycorrhizal fungi also notably increased the content of water-stable aggregate in the size ranges 0.25-0.5 mm and 0.5-1 mm but significantly reduced them in the 1-2 mm size range. There was no effect on water-stable aggregate content in the 2-4 mm size and mean weight diameter (an indicator of soil aggregate stability). Inoculated treatments markedly increased rhizospheric soil easily-extractable GRSP,total GRSP,hot-water extractable and hydrolyzed carbohydrate contents. Correlation analysis showed that root mycorrhizal colonization was highly positively correlated with GRSP production,and GRSP had a positive effect on <1 mm size water-stable aggregates. In addition,the contribution of GRSPs to aggregate stability mainly depends on total GRSP but not on easily-extractable GRSP. GRSP fractions had different contributions to soil carbohydrates.

盆栽条件下研究丛枝菌根真菌(地表球囊霉和隐类球囊霉)对白三叶生长、叶绿素含量、根际土壤水稳性团聚体粒级分布和稳定性,以及球囊霉素相关土壤蛋白(GRSP)和糖类物质含量的影响。结果表明,接种85 d后根系菌根侵染率为35%~75%。接种处理显著提高了地上部、地下部和植株总干物质量以及叶绿素含量,其中白三叶对隐类球囊霉的依赖性高于地表球囊霉。接种菌根真菌处理也增加了根际0.25~0.5 mm和0.5~1 mm粒径水稳性团聚体含量,降低了1~2 mm粒径水稳性团聚体含量,但没有影响2~4 mm粒径水稳性团聚体含量以及平均质量直径。菌根接种增加了白三叶根际土壤易提取GRSP、总GRSP、热水提取碳水化合物和水解碳水化合物的含量。相关性分析显示,根系菌根侵染率显著地促进GRSP的含量,GRSP主要对<1 mm粒级水稳性团聚体产生正效应,团聚体稳定性主要依赖总GRSP,不同组分的GRSP对土壤糖类物质的贡献不同。

Heavy-metal pollution in soil is a major threat to human health and the whole ecosystem, while bioremediation has become a promising option to recover the contaminated soils for its effective, non-intrusive and inexpensive. In particular, the application of symbiotic micro-organisms such as mycorrhizal fungi to enhance bioremediation efficiency has been paid more and more attention. Arbuscular mycorrhizal (AM) fungi are one of the widely spread micro-organisms, which could form symbionts with most of the vascular plants in natural or artificial ecosystem. It has demonstrated that AM symbionts could increase the stressed ability of host plants in heavy metal polluted soil. Nowadays, using bioremediation methods to recovery heavy metal polluted soils with AM fungi has been one of the hotspots in environmental and ecological science. In order to review the physiological and molecular mechanism of heavy metals tolerance induced by AM fungi, four strategies were discussed in this paper: 1) the physical defense system formation, 2) the regulation to physiological metabolism of plants, 3) the production of biochemical antagonist material and 4) the regulation of gene expression. On the basis of this, this paper indicated that the possibility of using the system of AM-soil microbiology-host plant for remediation of heavy metals polluted soil in the future. For this purpose, to enhance the studies below would be necessary: 1) molecular mechanisms that AM fungi regulate heavy metal uptake and translocation; 2) phytoremediation of polymetal-contaminated soils through selection of heavy metal tolerant AM fungi strains by genetic engineering; 3) the combination of other remediation techniques and AM-assisted bioremediation.

土壤重金属污染威胁人类健康和整个生态系统,而高效、低耗、安全的生物修复技术显示出了极大的应用潜力,特别是利用植物-微生物共生体增强生物修复效应的应用。丛枝菌根(Arbuscular Mycorrhizae,AM)真菌是一类广泛分布于土壤生态系统中的有益微生物,能与90%以上的陆生高等植物形成共生体。研究发现,AM真菌能够增强宿主植物对土壤中重金属胁迫的耐受性。当前,利用AM真菌开展重金属污染土壤的生物修复已经引起环境学家和生态学家的广泛关注。基于此,围绕AM真菌在重金属污染土壤生物修复作用中的最新研究进展,从物理性防御体系的形成、对植物生理代谢的调控、生化拮抗物质的产生、基因表达的调控等角度探究AM真菌在重金属污染土壤生物修复中的作用机理,以期为利用AM真菌开展重金属污染的生物修复提供理论依据,并对本领域未来的发展和应用前景进行了展望。

Coal mining has aided economic development but has also caused serious environmental problems. This paper reviews the major soil barriers to successful ecological restoration such as low soil fertility, low or high pH, low water holding capacity, high erodibility and extremely high temperature and poor soil microbial activity. Mining activities have severe deleterious effects on plants and the soil microbial community that must be ameliorated with additional amendments in order to achieve successful re-vege...

煤炭开采在促进国民经济快速发展的同时,引发诸多生态环境问题,分别就矿区生态治理中存在的主要障碍因子进行论述,结合丛枝菌根对宿主植物的营养吸收和抗逆性能,综述了丛枝菌根在矿区生态重建中应用的研究进展,揭示出菌根应用在矿区生态重建中的作用潜力和研究方向,极大地提高了矿区生态恢复的质量。

Arbuscular mycorrhizal fungi (AMF) are beneficial microorganisms, distributed widely in many different soil types. The investigation of species diversity of AMF in extreme environments is a rapidly developing area of research because of the potential benefits for ecosystem restoration. Screening for effective arbuscular mycorrhizal fungi species is regarded as an important approach to successful revegetation. The identification of arbuscular mycorrhizal species and their distribution were investigated in 15 natural saline-alkaline Leymus chinensis grasslands in 12 regions of the western Songnen Plain. The occurrence frequency, species richness and spore density were also investigated. The ability of AMF to infect roots of L. chinensis , including colonization rate and infection intensity, and the effect of soil pH were measured. In total, 11 species from 4 different families were identified; 72.4% of species belonged to Glomus . One species, G. mossea , was found at all sites. High soil pH strongly decreased AMF species richness in natural saline-alkaline communities of L. chinensis , but did not affect spore density. Disturbance of soil through erosion may be an important factor influencing spore density in soil because AMF spores were seldom detected in bare soil where the surface had been significantly disturbed. Root colonization rate was positively correlated with infection intensity. The infection of L. chinensis roots was increased with increasing AMF species richness, depressed by increasing soil pH. Our research indicated that there was an abundance of AMF species in saline-alkaline grassland able to infect roots of L. chinensis , and suggested approaches for screening saline-alkaline tolerant AMF species with the potential to help restore the degraded grassland ecosystem on the Songnen Plain.

本研究在松嫩平原西部12个地区15个重度盐碱化草地中,调查了羊草群落天然斑块中AM真菌的种类和分布、AM真菌羊草根系的侵染能力及土壤pH值的影响。共分离出AM真菌4属11种,其中球囊霉属( Glomus )占总物种数的72.42%,在各调查样点中出现频度最高,其中摩西球囊霉( G. mossea )出现频度达100.0%。土壤pH强烈抑制盐碱化草地中羊草天然群落斑块中AM真菌的物种丰富度,但对孢子密度的影响未达到显著水平。AM真菌对羊草根系的侵染频率和侵染强度显著正相关。AM真菌对羊草根系的侵染频率和侵染强度随着AM物种数量的增加而增强,随着土壤pH的增加而下降。在盐碱化羊草地中存在较丰富的侵染羊草根系的AM真菌资源,研究结果为筛选和利用耐盐碱AM真菌菌株以恢复和重建松嫩盐碱化羊草草地生态系统提供了理论依据。

As one of the essential elements for plant, nitrogen (N) plays an important role in predicting the primary productivity in terrestrial ecosystems. On the other hand, arbuscular mycorrhizal fungi (AMF), a group of ubiquitous soil fungi that form symbiotic association with the majority of the terrestrial vascular plants, play a vital role in plant growth by providing their host plants with mineral nutrients such as phosphorus (P) and N, and trace elements. AMF can also protect plants from drought stress, pathogen infections and heavy metal contaminations, and improve soil structure by influencing soil aggregation dynamics. Recent studies on AMF and N cycling were mainly focused on the N forms absorbed by AMF and the N metabolism and translocation in the symbiosis. It has been well demonstrated that AMF can take up different N forms such as inorganic N, amino acids, and even complex organic N. AMF prefer to assimilate ammonium than nitrate in most circumstances. The N transfer and translocation via AMF has also been extensively studied. Various N sources are firstly incorporated into arginine (Arg) through the urea cycle in the extraradical mycelium (ERM), and then transported to the intraradical mycelium (IRM) possibly with polyphosphate (PolyP). Finally, Arg is catabolized through the catabolic arm of the urea cycle in the IRM, releasing NH 3 /NH 4 + into arbuscules. In contrast to good knowledge of N metabolism in the mycorrhizal symbiosis, the possible involvements of AMF in soil N cycling processes such as mineralization of organic N, N fixation, nitrification, denitrification and leaching has been largely overlooked. However, AMF may mediate the soil N cycling process via different pathways from the smallest to the largest spatio-temporal scale, and much attention has been paid to the involvement of AMF in soil N cycling in recent years. The interaction of AMF and other functional microbial groups responsible for N cycling has been particularly studied. It has been well demonstrated that AMF had remarkable effects on diazotrophic, nitrifying and denitrifying microbial communities in soil microcosms or under field conditions. AMF were also shown to reduce soil inorganic N loss via leaching in microcosm-based studies. Taken together, AMF can serve as an important influencing factor for individual soil N cycling processes. Furthermore, the belowground common mycorrhizal networks could essentially affect N transfer and re-allocation among different plants in ecosystems, and thus have important ecological impacts on aboveground plant community and ecosystem stability. Moreover, all AMF hyphae have a high N content, thus the N pool in AMF mycelia could be similar in magnitude to that in roots considering their ubiquity in terrestrial ecosystems. The fungal hyphae also have a rapid turnover rate, indicating that AMF play an unappreciated role in global N cycling. This paper summarized the recent research progresses in N metabolism in AM symbiosis, including N species assimilated by AMF, and the N metabolism genes in AMF. Simultaneously, the potential role of AMF in mediating the soil N cycling processes and its ecological significances in ecosystems were discussed in details. Some important issues in relation to the involvement of AMF in soil N cycling were also proposed for further research.

作为植物需求量最大的营养元素，氮素是陆地生态系统初级生产力的主要限制因子。丛枝菌根真菌能与地球上80%以上的陆生植物形成菌根共生体，帮助宿主植物吸收土壤中的P、N等矿质养分。目前，丛枝菌根真菌与氮素循环相关研究侧重于真菌对氮素的吸收形态以及共生体中氮的传输代谢机制，却忽略了丛枝菌根真菌在固氮过程、矿化与吸收过程、硝化过程、反硝化过程以及氮素淋洗过程等土壤氮素循环过程中所起到的潜在作用，并且越来越多的证据也表明丛枝菌根真菌是影响土壤氮素循环过程的重要因子。总结了丛枝菌根真菌可利用的氮素形态及真菌的氮代谢转运相关基因的研究现状；重点分析了丛枝菌根真菌在调控土壤氮素循环过程中的潜在作用以及在生态系统中的重要生态学意义，同时提出了丛枝菌根真菌在土壤氮素循环过程中一些需要深入研究的问题。

A greenhouse pot experiment was conducted to investigate the effects of arbuscular mycorrhiza (AM) on microbes and soil enzymes in rhizosphere and hyphosphere soil contaminated by phenanthrene and pyrene. The quantities of bacteria, fungi, and actinomyces in both rhizosphere and hyphosphere increased significantly, and the microflora changed with the inoculation of arbuscular mycorrhizal fungi (AMF). The soil contamination of phenanthrene and pyrene with lower concentration clearly stimulated the activity of enzymes including acid phosphatase, polyphenol oxidase and catalase. However, when the contamination dose was higher, their activities were inhibited. Compared with bulk soil, the activity of acid phosphatase in rhizosphere with AMF was decreased by 2.4%~23.1%, and catalase in rhizosphere was decreased by 12.6%~20.3%. By contrast, the activity of polyphenol oxidase in rhizosphere was stimulated except those treatments with high levels of PAH. Polyphenol oxidase activity in hyphosphere was 2.9%~62.9% lower, while acid phosphatase activity was 3.3%~24.0% higher than that in rhizosphere. In general, catalase activity in hyphosphere was higher than that in rhizosphere. In addition, both AM and hypha enhanced the activity of catalase in soils. The enhanced activity of polyphenol oxidase by AM in rhizosphere could be the results of improved plant growth and root activities with AMF inoculation.

采用温室盆栽试验方法,研究了丛枝菌根真菌(AMF)对菲、芘复合污染土壤中微生物数量和酶活性的影响.结果表明,接种AMF显著增加了三叶草根际和菌丝际土壤中细菌、真菌和放线菌的数量,并对微生物区系有选择性.在供试菲、芘污染浓度范围内,低浓度菲、芘对土壤多酚氧化酶、酸性磷酸酶和过氧化氢酶活性有激活作用;但当菲、芘浓度升高时,3种酶活性受到抑制.与无植物对照土壤相比,接种AMF后三叶草菌根际酸性磷酸酶活性降低了2.4%~23.1%,过氧化氢酶活性增加了12.6%~20.3%,除高浓度处理外多酚氧化酶活性均增加;菌丝际多酚氧化酶活性比菌根际低12.9%~62.9%,酸性磷酸酶活性比菌根际高3.3%~24.0%,过氧化氢酶活性则高于菌根际.

The effects of two arbuscular mycorrhizal fungi ( Glomus versiforme and Paraglomus occultum ) on size distribution of soil water-stable aggregate and aggregate stability,glomalin-related soil protein (GRSP),and carbohydrates of white clover ( Trifolium repens ) were analyzed. Root mycorrhizal infection ranged from 35% to 75% after 85 days of mycorrhizal inoculation. The inoculated treatments significantly increased shoot,root,and total dry biomass and chlorophyll content. White clover was more dependent on P. occultum than on G. mosseae . The treatments inoculated with arbuscular mycorrhizal fungi also notably increased the content of water-stable aggregate in the size ranges 0.25-0.5 mm and 0.5-1 mm but significantly reduced them in the 1-2 mm size range. There was no effect on water-stable aggregate content in the 2-4 mm size and mean weight diameter (an indicator of soil aggregate stability). Inoculated treatments markedly increased rhizospheric soil easily-extractable GRSP,total GRSP,hot-water extractable and hydrolyzed carbohydrate contents. Correlation analysis showed that root mycorrhizal colonization was highly positively correlated with GRSP production,and GRSP had a positive effect on <1 mm size water-stable aggregates. In addition,the contribution of GRSPs to aggregate stability mainly depends on total GRSP but not on easily-extractable GRSP. GRSP fractions had different contributions to soil carbohydrates.

盆栽条件下研究丛枝菌根真菌(地表球囊霉和隐类球囊霉)对白三叶生长、叶绿素含量、根际土壤水稳性团聚体粒级分布和稳定性,以及球囊霉素相关土壤蛋白(GRSP)和糖类物质含量的影响。结果表明,接种85 d后根系菌根侵染率为35%~75%。接种处理显著提高了地上部、地下部和植株总干物质量以及叶绿素含量,其中白三叶对隐类球囊霉的依赖性高于地表球囊霉。接种菌根真菌处理也增加了根际0.25~0.5 mm和0.5~1 mm粒径水稳性团聚体含量,降低了1~2 mm粒径水稳性团聚体含量,但没有影响2~4 mm粒径水稳性团聚体含量以及平均质量直径。菌根接种增加了白三叶根际土壤易提取GRSP、总GRSP、热水提取碳水化合物和水解碳水化合物的含量。相关性分析显示,根系菌根侵染率显著地促进GRSP的含量,GRSP主要对<1 mm粒级水稳性团聚体产生正效应,团聚体稳定性主要依赖总GRSP,不同组分的GRSP对土壤糖类物质的贡献不同。

Heavy-metal pollution in soil is a major threat to human health and the whole ecosystem, while bioremediation has become a promising option to recover the contaminated soils for its effective, non-intrusive and inexpensive. In particular, the application of symbiotic micro-organisms such as mycorrhizal fungi to enhance bioremediation efficiency has been paid more and more attention. Arbuscular mycorrhizal (AM) fungi are one of the widely spread micro-organisms, which could form symbionts with most of the vascular plants in natural or artificial ecosystem. It has demonstrated that AM symbionts could increase the stressed ability of host plants in heavy metal polluted soil. Nowadays, using bioremediation methods to recovery heavy metal polluted soils with AM fungi has been one of the hotspots in environmental and ecological science. In order to review the physiological and molecular mechanism of heavy metals tolerance induced by AM fungi, four strategies were discussed in this paper: 1) the physical defense system formation, 2) the regulation to physiological metabolism of plants, 3) the production of biochemical antagonist material and 4) the regulation of gene expression. On the basis of this, this paper indicated that the possibility of using the system of AM-soil microbiology-host plant for remediation of heavy metals polluted soil in the future. For this purpose, to enhance the studies below would be necessary: 1) molecular mechanisms that AM fungi regulate heavy metal uptake and translocation; 2) phytoremediation of polymetal-contaminated soils through selection of heavy metal tolerant AM fungi strains by genetic engineering; 3) the combination of other remediation techniques and AM-assisted bioremediation.

土壤重金属污染威胁人类健康和整个生态系统,而高效、低耗、安全的生物修复技术显示出了极大的应用潜力,特别是利用植物-微生物共生体增强生物修复效应的应用。丛枝菌根(Arbuscular Mycorrhizae,AM)真菌是一类广泛分布于土壤生态系统中的有益微生物,能与90%以上的陆生高等植物形成共生体。研究发现,AM真菌能够增强宿主植物对土壤中重金属胁迫的耐受性。当前,利用AM真菌开展重金属污染土壤的生物修复已经引起环境学家和生态学家的广泛关注。基于此,围绕AM真菌在重金属污染土壤生物修复作用中的最新研究进展,从物理性防御体系的形成、对植物生理代谢的调控、生化拮抗物质的产生、基因表达的调控等角度探究AM真菌在重金属污染土壤生物修复中的作用机理,以期为利用AM真菌开展重金属污染的生物修复提供理论依据,并对本领域未来的发展和应用前景进行了展望。

Coal mining has aided economic development but has also caused serious environmental problems. This paper reviews the major soil barriers to successful ecological restoration such as low soil fertility, low or high pH, low water holding capacity, high erodibility and extremely high temperature and poor soil microbial activity. Mining activities have severe deleterious effects on plants and the soil microbial community that must be ameliorated with additional amendments in order to achieve successful re-vege...

煤炭开采在促进国民经济快速发展的同时,引发诸多生态环境问题,分别就矿区生态治理中存在的主要障碍因子进行论述,结合丛枝菌根对宿主植物的营养吸收和抗逆性能,综述了丛枝菌根在矿区生态重建中应用的研究进展,揭示出菌根应用在矿区生态重建中的作用潜力和研究方向,极大地提高了矿区生态恢复的质量。

Arbuscular mycorrhizal fungi (AMF) are beneficial microorganisms, distributed widely in many different soil types. The investigation of species diversity of AMF in extreme environments is a rapidly developing area of research because of the potential benefits for ecosystem restoration. Screening for effective arbuscular mycorrhizal fungi species is regarded as an important approach to successful revegetation. The identification of arbuscular mycorrhizal species and their distribution were investigated in 15 natural saline-alkaline Leymus chinensis grasslands in 12 regions of the western Songnen Plain. The occurrence frequency, species richness and spore density were also investigated. The ability of AMF to infect roots of L. chinensis , including colonization rate and infection intensity, and the effect of soil pH were measured. In total, 11 species from 4 different families were identified; 72.4% of species belonged to Glomus . One species, G. mossea , was found at all sites. High soil pH strongly decreased AMF species richness in natural saline-alkaline communities of L. chinensis , but did not affect spore density. Disturbance of soil through erosion may be an important factor influencing spore density in soil because AMF spores were seldom detected in bare soil where the surface had been significantly disturbed. Root colonization rate was positively correlated with infection intensity. The infection of L. chinensis roots was increased with increasing AMF species richness, depressed by increasing soil pH. Our research indicated that there was an abundance of AMF species in saline-alkaline grassland able to infect roots of L. chinensis , and suggested approaches for screening saline-alkaline tolerant AMF species with the potential to help restore the degraded grassland ecosystem on the Songnen Plain.

本研究在松嫩平原西部12个地区15个重度盐碱化草地中,调查了羊草群落天然斑块中AM真菌的种类和分布、AM真菌羊草根系的侵染能力及土壤pH值的影响。共分离出AM真菌4属11种,其中球囊霉属( Glomus )占总物种数的72.42%,在各调查样点中出现频度最高,其中摩西球囊霉( G. mossea )出现频度达100.0%。土壤pH强烈抑制盐碱化草地中羊草天然群落斑块中AM真菌的物种丰富度,但对孢子密度的影响未达到显著水平。AM真菌对羊草根系的侵染频率和侵染强度显著正相关。AM真菌对羊草根系的侵染频率和侵染强度随着AM物种数量的增加而增强,随着土壤pH的增加而下降。在盐碱化羊草地中存在较丰富的侵染羊草根系的AM真菌资源,研究结果为筛选和利用耐盐碱AM真菌菌株以恢复和重建松嫩盐碱化羊草草地生态系统提供了理论依据。

As one of the essential elements for plant, nitrogen (N) plays an important role in predicting the primary productivity in terrestrial ecosystems. On the other hand, arbuscular mycorrhizal fungi (AMF), a group of ubiquitous soil fungi that form symbiotic association with the majority of the terrestrial vascular plants, play a vital role in plant growth by providing their host plants with mineral nutrients such as phosphorus (P) and N, and trace elements. AMF can also protect plants from drought stress, pathogen infections and heavy metal contaminations, and improve soil structure by influencing soil aggregation dynamics. Recent studies on AMF and N cycling were mainly focused on the N forms absorbed by AMF and the N metabolism and translocation in the symbiosis. It has been well demonstrated that AMF can take up different N forms such as inorganic N, amino acids, and even complex organic N. AMF prefer to assimilate ammonium than nitrate in most circumstances. The N transfer and translocation via AMF has also been extensively studied. Various N sources are firstly incorporated into arginine (Arg) through the urea cycle in the extraradical mycelium (ERM), and then transported to the intraradical mycelium (IRM) possibly with polyphosphate (PolyP). Finally, Arg is catabolized through the catabolic arm of the urea cycle in the IRM, releasing NH 3 /NH 4 + into arbuscules. In contrast to good knowledge of N metabolism in the mycorrhizal symbiosis, the possible involvements of AMF in soil N cycling processes such as mineralization of organic N, N fixation, nitrification, denitrification and leaching has been largely overlooked. However, AMF may mediate the soil N cycling process via different pathways from the smallest to the largest spatio-temporal scale, and much attention has been paid to the involvement of AMF in soil N cycling in recent years. The interaction of AMF and other functional microbial groups responsible for N cycling has been particularly studied. It has been well demonstrated that AMF had remarkable effects on diazotrophic, nitrifying and denitrifying microbial communities in soil microcosms or under field conditions. AMF were also shown to reduce soil inorganic N loss via leaching in microcosm-based studies. Taken together, AMF can serve as an important influencing factor for individual soil N cycling processes. Furthermore, the belowground common mycorrhizal networks could essentially affect N transfer and re-allocation among different plants in ecosystems, and thus have important ecological impacts on aboveground plant community and ecosystem stability. Moreover, all AMF hyphae have a high N content, thus the N pool in AMF mycelia could be similar in magnitude to that in roots considering their ubiquity in terrestrial ecosystems. The fungal hyphae also have a rapid turnover rate, indicating that AMF play an unappreciated role in global N cycling. This paper summarized the recent research progresses in N metabolism in AM symbiosis, including N species assimilated by AMF, and the N metabolism genes in AMF. Simultaneously, the potential role of AMF in mediating the soil N cycling processes and its ecological significances in ecosystems were discussed in details. Some important issues in relation to the involvement of AMF in soil N cycling were also proposed for further research.

作为植物需求量最大的营养元素，氮素是陆地生态系统初级生产力的主要限制因子。丛枝菌根真菌能与地球上80%以上的陆生植物形成菌根共生体，帮助宿主植物吸收土壤中的P、N等矿质养分。目前，丛枝菌根真菌与氮素循环相关研究侧重于真菌对氮素的吸收形态以及共生体中氮的传输代谢机制，却忽略了丛枝菌根真菌在固氮过程、矿化与吸收过程、硝化过程、反硝化过程以及氮素淋洗过程等土壤氮素循环过程中所起到的潜在作用，并且越来越多的证据也表明丛枝菌根真菌是影响土壤氮素循环过程的重要因子。总结了丛枝菌根真菌可利用的氮素形态及真菌的氮代谢转运相关基因的研究现状；重点分析了丛枝菌根真菌在调控土壤氮素循环过程中的潜在作用以及在生态系统中的重要生态学意义，同时提出了丛枝菌根真菌在土壤氮素循环过程中一些需要深入研究的问题。

A greenhouse pot experiment was conducted to investigate the effects of arbuscular mycorrhiza (AM) on microbes and soil enzymes in rhizosphere and hyphosphere soil contaminated by phenanthrene and pyrene. The quantities of bacteria, fungi, and actinomyces in both rhizosphere and hyphosphere increased significantly, and the microflora changed with the inoculation of arbuscular mycorrhizal fungi (AMF). The soil contamination of phenanthrene and pyrene with lower concentration clearly stimulated the activity of enzymes including acid phosphatase, polyphenol oxidase and catalase. However, when the contamination dose was higher, their activities were inhibited. Compared with bulk soil, the activity of acid phosphatase in rhizosphere with AMF was decreased by 2.4%~23.1%, and catalase in rhizosphere was decreased by 12.6%~20.3%. By contrast, the activity of polyphenol oxidase in rhizosphere was stimulated except those treatments with high levels of PAH. Polyphenol oxidase activity in hyphosphere was 2.9%~62.9% lower, while acid phosphatase activity was 3.3%~24.0% higher than that in rhizosphere. In general, catalase activity in hyphosphere was higher than that in rhizosphere. In addition, both AM and hypha enhanced the activity of catalase in soils. The enhanced activity of polyphenol oxidase by AM in rhizosphere could be the results of improved plant growth and root activities with AMF inoculation.

采用温室盆栽试验方法,研究了丛枝菌根真菌(AMF)对菲、芘复合污染土壤中微生物数量和酶活性的影响.结果表明,接种AMF显著增加了三叶草根际和菌丝际土壤中细菌、真菌和放线菌的数量,并对微生物区系有选择性.在供试菲、芘污染浓度范围内,低浓度菲、芘对土壤多酚氧化酶、酸性磷酸酶和过氧化氢酶活性有激活作用;但当菲、芘浓度升高时,3种酶活性受到抑制.与无植物对照土壤相比,接种AMF后三叶草菌根际酸性磷酸酶活性降低了2.4%~23.1%,过氧化氢酶活性增加了12.6%~20.3%,除高浓度处理外多酚氧化酶活性均增加;菌丝际多酚氧化酶活性比菌根际低12.9%~62.9%,酸性磷酸酶活性比菌根际高3.3%~24.0%,过氧化氢酶活性则高于菌根际.