红树林真菌的生物多样性和生物工程应用潜力(英文)

本文对现今红树林真菌研究的热点领域进行了综述,包括红树林真菌的生物多样性,生态作用,新颖的代谢产物和生物工程应用前景四个方面。首先,红树林真菌按照其生态作用被分为腐生,寄生和内生真菌。其中腐生真菌对于红树林生态系统的降解和能量循环方面起着重要的作用,另外,它们也会产生一些毒素:寄生真菌对于红树林的存活,长势和健康程度起着重要的作用;而内生真菌分布于大部分红树之中,所产的活性物质是红树林真菌中最丰富的。其次,虽然已有大量文献报道了红树林真菌可以产生很多新酶和具有’抑菌,杀虫及其它活性的物质,并且很多由内生真菌产生的活性物质被认为对红树起着重要作用,但只有少量研究对此提供了有力的证据,因此,本文对现今应用分子技术来将红树林真菌的生态作用与其代谢产物联系起来的进展进行了讨论。最后,本文还讨论了利用代谢工程和后基因组技术来生产大量新酶和活性物质并将其商业化应用的前景。     

惠东县红树林保护区植被调查及恢复初探

惠东县红树林保护区及其周边陆域植被类型复杂多样。保护区红树林主要分布在稔山、铁涌、盐洲三镇,现有15种红树植物,约占中国红树植物种数的38.46%。其中真红树10种,约占中国真红树植物种数的35.71%;半红树5种,约占中国半红树植物种数的45.45%。其中稔山有红树植物12种,包括原生真红树植物8种、外来真红树植物1种和半红树植物3种;铁涌有红树植物12种,包括原生真红树植物7种、外来真红树植物1种和半红树植物4种;盐洲有红树植物12种,包括原生真红树植物8种、半红树植物3种和外来真红树植物1种。惠东县红树林保护区的植物种类资源具有较高的欣赏价值和物种保护价值,对惠东县红树林保护区植被调查及其周边区域陆域植物生态调查研究,为惠东县红树林保护区未来的发展及红树林生态系统的安全提供有力的保障和基础理论依据。     

独特的海滨森林──红树林

独特的海滨森林──红树林李云人们常常以为红树林全是红色的，其实红树林是包括红树科植物为主的森林，而红树科的红树植物又多含单宁，树皮或木材常见红褐色，所以人们称其为“红树”。红树林主要分布于热带、亚热带地区隐蔽的海滨，也可生长在常有海水渗透的河口、泻湖...     

中国红树植物的引种栽培状况

在对全国各主要红树林分布区实施调查的基础上，论述了全国各省区红树植物的中国红树植物种类及分布表。针对各省区红树林要树种单一的情况，提出了一个各省区红树植物引种栽培的优先选择树种方案。     

钦州市红树林资源现状与保护对策

钦州市有红树植物9种，半红树植物3种，红树林伴生植物4种。红树林面积3057.3hm^2，被占红树林面积1074.9hm^2，红树林面积中树高等级在2m以下2353.4hm^2，占77％，盖度在70％以下1646.8hm^2，占54％；Ⅱ级自然度红树林有2180.6hm^2，占红树林面积的71％；质量明显下降，建议尽快理顺有关管理部门的关系并建立红树林保护区，以保护和恢复钦州市的红树林资源，实现生态平衡和资源的可持续发展。     

湛江市红树林资源状况及其保护成效

湛江市是除海南岛外我国红树植物种类最多的地区，是我国红树林主要分布区之一，也是广东省红树林分布最广、面积最大、红树林物种最丰富的地级市，其中红树植物有12科、16属、17种。本文简要地介绍了湛江市红树林资源状况、中荷合作广东雷州半岛红树林综合管理和沿海保护项目在保护红树林方面所取得的一些成效，以及此项工作的开展对湛江市可持续发展具有的重要意义。     

惠东县红树林资源现状及保护对策

通过卫星遥感和设置样地对广东省惠东县的红树林资源进行调查.结果表明:惠东县红树林面积共有1361.83 hm2,其中,红树林有林地有400.15 hm2,红树林未成林造林地有42.27 hm2,红树林宜林地有919.41 hm2;共分布15种红树植物,其中真红树植物有9种,半红树植物有6种,另外红树林伴生植物有29种....     

中国红树植物的引种栽培状况

在对全国各主要红树林分布区实地调查的基础上,论述了全国各省区红树植物（包括半红树植物）引种栽培状况,提出了一个完整的中国红树植物（包括半红树植物）种类及分布表。针对各省区红树林造林树种单一的情况,提出了一个各省区红树植物引种栽培的优先选择树种方案。     

红树植物亲缘地理学研究进展

红树植物生长在热带、亚热带海岸滩涂上。健全的红树植物生态系统是人类持续利用红树林的必要条件。如何保护、维持红树林的生态系统及其遗传健全性已成为红树林生态学家最关心的问题。红树植物当前的地理分布格局及形成原因是生态学家和保护生态学家的研究重点。文中介绍了近些年来红树植物亲缘地理学研究概况,包括地理隔离对红树植物分布格局的影响、基因交流受阻隔以及引起红树群体遗传结构变化的原因等内容;阐述了地质历史引起地形地貌变化、地理隔离、繁殖体扩散及生境环境等因子影响红树群体遗传演化的机制;探讨了红树植物亲缘地理学未来研究的重点,以期为红树植物保护和相关研究提供参考。     

浙江省红树林资源调查及其发展规划

据2001年调查，浙江省共有红树和半红树植物3种，即秋茄、苦槛蓝、海滨木槿。全省现有红树林20．6hm^2，未成林红树林地236．1hm^2，宜林地面积5195．6hm^2。分析了红树林的现状特点，提出了浙江省红树林立地分类系统，最后进行了红树林发展规划。     

印度东北部黄兰种植区丛枝菌根真菌的侵染和分布(英文)

调查了印度东北部梅加拉亚邦(Meghalaya)3个黄兰种植区(Umdihar,Umsaw和Mawlein)内丛枝菌根真菌和暗隔真菌的侵染。分离和鉴定了丛枝菌根真菌孢子,根据不同黄兰种植区内菌根菌种分布和丰富度评价了菌根菌多样性和寄主选择性。结果表明,丛枝菌根真菌侵染显著高于暗隔真菌。丛枝菌根真菌和暗隔真菌的侵染分别是50.91%～58.95%和1.84%～4.11%。真菌孢子密度在三个种植区内变化较大(p0.05)。在所鉴定的7个属29个菌种中,球囊霉属菌种的丰富度最高。Sorenson系数在0.35-7.0之间。种植区内菌种丰富度在2.0～2.9之间。总的菌种丰富度与总的相对丰富度显著相关(p=0.001)。真菌分布、相对丰富度和主成分分析结果表明,大果球囊霉(Glomus macrocarpum)、Glomus multicaulic、缩不囊霉(G.constrictum)和无梗囊霉是黄兰最偏好的菌种,可能是由于寄主的营养获得和生长较为适当。图6表5参27。     

Growth response, phosphorus content and root colonization of Polylepis australis Bitt. seedlings inoculated with different soil types

Polylepis forests are one of the most endangered high mountain ecosystems of South America and reforestation with native Polylepis species has been highly recommended. Greenhouse bioassays were set up to determine the influence of three different soils on growth and phosphorous nutrition of Polylepis australis seedlings. Soils were collected from a grassland, a rare mature forest and a forest degraded due to repeated fires. We identified the arbuscular mycorrhizal fungi (AMF) present in the three soils and after 12 months we harvested the seedlings to evaluate root and shoot biomass, plant P content and root colonization by native AMF and dark septate endophytes (DSE). The soil inocula contained 26 AMF morphospecies. Grassland inoculum showed the highest AMF richness, and mature forest showed a different AMF community assembly from grassland and degraded forest inocula. Root biomass and root colonization were highest in seedlings inoculated with mature forest soil, meanwhile shoot biomass and plant P content were similar between all treatments. AMF colonization correlated negatively with DSE and root biomass was negatively correlated with DSE colonization, thus these fungal symbionts could be competing for resources. Our results indicate that AMF inoculum from the mature forest stand has the potential to improve P. australis performance, probably due to the dominance of Glomeraceae and Acaulosporaceae families. However, other soil microorganisms could be together with AMF in the natural inocula, affecting the growth response of P. australis seedlings. Future studies evaluating the effect of these inocula under field conditions should be carried out.     

Tree species as hosts for arbuscular mycorrhizal and dark septate endophyte fungi

A survey of 35 tree species(belonging to 28 genera in 19 families) in Aliyar,South India was carried out to ascertain their arbuscular mycorrhizal(AM) and dark septate endophyte(DSE) fungal status.All the tree species examined had AM association.AM and DSE colonization is reported for the first time in 20 and 14 species respectively.Cooccurrence of AM and DSE was observed in 14(40%) tree species.The extent of DSE colonization was inversely related to the extent of AM fungal colonization.Six tree species had Arum-type,18 had intermediatetype and 11 had typical Paris-type AM morphology.AM fungal spore morphotypes belonging to 11 species in two genera were isolated from the rhizosphere soil.AM fungal spore numbers were not related to the extent of AM colonization and Glomus dominated spore diversity.AM association individually and along with DSE were found respectively in the 63% and 44% of the economically important tree species.The occurrence of AM and DSE fungal association in economically important indigenous tree species indicates the possibility of exploiting this association in future conservation programmes of these species.     

Different arbuscular mycorrhizae and competition with an exotic grass affect the growth of Podocarpus cunninghamii Colenso cuttings

There is growing interest in the use of arbuscular mycorrhizal fungi (AMF) for ecological restoration. Numerous commercial AMF products are now available and are often used in preference to collecting indigenous AMF in treating restoration plants. Commercial AMF products are typically based on AMF strains exotic to the plant species and locations where they are used. We treated rooted cuttings of an endemic New Zealand tree species (Podocarpus cunninghamii) and an exotic and invasive grass (Agrostis capillaris) with an indigenous, pot-cultured AMF (Acaulospora laevis) and an exotic commercial AMF product (Glomus spp.). P. cunninghamii was grown in monoculture and together with A. capillaris, the latter to simulate field competition that often occurs in restoration plantings. In monoculture, the indigenous AMF resulted in significant increases in P. cunninghamii growth rates and tissue concentrations of both nitrogen and phosphorus. The commercial AMF had either no effect or a negative effect on P. cunninghamii growth and nutrient levels. A. capillaris growth and nutrient status were unaffected by the different AMF treatments. Competition eliminated any AMF benefit for P. cunninghamii. The results show that, for our chosen indigenous woody plant species, the commercially available AMF did not improve its early growth and nutrient acquisition in monoculture while, over the same period, the indigenous AMF induced positive growth and nutrient responses. These results have potential implications for forest restoration, particularly for nursery production of indigenous woody species.     

Biodiversity of arbuscular mycorrhizal fungi in Amygdalus scoparia Spach plantations and a natural stand

The biodiversity of arbuscular mycorrhizal fungi(AMF) was surveyed in the Kolm region of Iran in three adjacent sites, a natural stand, a 10-year-old and a 15-yearold plantation of Amygdalus scoparia. To date, there have been few studies of AMF biodiversity in Iran, especially in the western forests of the country. For this study, soil and root samples were taken from A. scoparia rhizosphere soil in spring and autumn. Almost half of the root length was colonized by AMF. We identified 13 AMF species belonging to Glomeraceae, Claroideoglomeraceae or Diversisporaceae. The three plantations differed in terms of soil electrical conductivity, organic C and P. Spore density was significant correlated with P concentration. Root length colonization was correlated only with soil Ca.Species diversity and richness were significantly correlated with soil N, P, organic C and spore density. AMF diversity in 15-year-old plantations was more similar to that in the natural stand than in the 10-year-old plantation. We confirmed that a 15-year-old plantation is not similar in terms of AMF colonization to natural stands. We conclude that more than 15 years are required for AMF colonization of plantations to resemble that of natural stands.     

香格里拉亚高山两种植被类型主要植物的丛枝菌根研究

以滇西北香格里拉亚高山地区生态严重退化的荒草坡植被类型和基本实现恢复的近原生林地植被类型中主要植物的丛枝菌根真菌(AMF)作为研究对象,对这些植物根系的AMF感染率及其根际土壤中的AMF孢子密度进行了调查研究。结果表明,荒草坡的10种植物和近原生林地的9种植物,均形成典型的丛枝菌根(AM)。荒草坡和近原生林植物根际土壤中的平均孢子密度分别为674±221(SE)个/100g土和290±72个/100g土。单因素方差分析表明,两植被类型的主要植物在根系AMF菌丝感染率以及根际土壤中AMF孢子密度方面的差异都极显著。同种植物在近原生林地具有较高的AMF感染率,而根际土壤中的孢子密度则是在荒草坡为高。相关性分析表明,所调查植物的根系AMF菌丝感染率与根际土壤中的AMF孢子密度间不存在相关性。     

Biodiversity of arbuscular mycorrhizal fungi in <Emphasis Type="Italic">Amygdalus scoparia</Emphasis> Spach plantations and a natural stand

The biodiversity of arbuscular mycorrhizal fungi (AMF) was surveyed in the Kolm region of Iran in three adjacent sites, a natural stand, a 10-year-old and a 15-year-old plantation of Amygdalus scoparia. To date, there have been few studies of AMF biodiversity in Iran, especially in the western forests of the country. For this study, soil and root samples were taken from A. scoparia rhizosphere soil in spring and autumn. Almost half of the root length was colonized by AMF. We identified 13 AMF species belonging to Glomeraceae, Claroideoglomeraceae or Diversisporaceae. The three plantations differed in terms of soil electrical conductivity, organic C and P. Spore density was significant correlated with P concentration. Root length colonization was correlated only with soil Ca. Species diversity and richness were significantly correlated with soil N, P, organic C and spore density. AMF diversity in 15-year-old plantations was more similar to that in the natural stand than in the 10-year-old plantation. We confirmed that a 15-year-old plantation is not similar in terms of AMF colonization to natural stands. We conclude that more than 15 years are required for AMF colonization of plantations to resemble that of natural stands.     

The potential of arbuscular mycorrhizal fungi to conserve Kalappia celebica,an endangered endemic legume on gold mine tailings in Sulawesi,Indonesia

Kalapi(Kalappia celebica) is an endemic legume of Sulawesi and has been included in the endangered category since the early 1980 s.Conservation of the species is possible through ex situ culture techniques.Arbuscular mycorrhizal fungi(AMF) can accelerate plant growth which in turn supports the conservation of endangered species.This study aimed to assess the efficacy of local AMF to accelerate the growth of kalapi and increase nutrient uptake in kalapi grown in gold mine tailing media.There were three AMF treatments,Glomus claroideum,Glomus coronatum,and a mixture of both,plus the control.Each treatment was replicated three times,each consisting of five plants.The results show that the highest AMF colony was obtained by kalapi seedlings inoculated with Glomus coronatum and the mixture of AMF.The range of mycorrhizae inoculation effect values was 59.7-71.3%.AMF inoculation increased growth and dry weight of 4-month-old seedlings compared to controls.Dry and total weights of kalapi inoculated with G.coronatum were significantly different from those inoculated with the AMF mixture.However,they are not significantly different from kalapi inoculated with G.claroideum.The results also show that AMF increased nitrogen and phosphorous uptake by the roots,as well as nitrogen,phosphorous,potassium,manganese and iron by the shoots.All AMF treatments decreased potassium uptake in the roots,except in kalapi inoculated with G.coronatum.The AMF mixture decreased iron contents the roots by 15%.AMF can be developed into biofertilizer to support the conservation of kalapi in tropical Indonesia.     

Arbuscular mycorrhizal fungi communities associated with wild plants in a coastal ecosystem

Arbuscular mycorrhizal fungi(AMF) form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant communities.Yet little is known about the structure and composition of AMF communities on coastal beaches of eastern China.In this study,we investigated the occurrence,community composition and diversity of AMF associated with common wild plants on a coastal beach of North Jiangsu,China.Almost all of the local wild species were colonized by AMF except for Chenopodium album L.Thirty-seven AMF species were isolated from the rhizosphere belonging to 12 genera in seven families.Glomus was the dominant genus and Funneliformis mosseae the dominant species.The colonization,spore composition and diversity of AMF were strongly related to edaphic factors.Sodium(Na~+) ions in the soil significantly and negatively affected the colonization rate by AMF and both soil Na~+ levels and pH had a significant negative effect on AMF spore density and evenness.However,there was a significant positive correlation between species richness and total organic carbon.The results provide insights into soil factors affecting native AMF communities in coastal beach habitats which could benefit vegetation recovery and soil reclamation efforts.     

Effect of mangrove restoration on crab burrow density in Luoyangjiang Estuary,China

Background:Mangrove restoration seeks to restore or rebuild degraded mangrove systems.The methods of mangrove restoration include ecological projects and restoration-oriented technologies,the latter of which are designed to restore the structure,processes as well as related physical,chemical and biological characteristics of wetlands and to ensure the provision of ecosystem services.As important components of mangrove ecosystem,benthic organisms and crabs play a key role in nutrient cycling.In addition,mangrove restoration,such as vegetation restoration measures,can lead to changes in the benthic faunal communities.This study investigates whether the presence of different mangrove species,age and canopy cover of mangrove communities affect the density of crab burrows.Methods:The Luoyangjiang Estuary,in the southeast of Fujian Province,was selected as our research area.A survey,covering 14 sites,was conducted to investigate the impacts of mangrove restoration on the density of crab burrows in four rehabilitated forests with different stand ages and canopy.Results:It was found that differences in vegetation types had a large impact on crab density and that the density of crab burrows was lower on exposed beaches(non-mangrove)than under mature Kandelia candel,Aegiceras corniculatum and Avicennia marina communities.In general,the amount of leaf litter and debris on mangrove mudflats was greater than on the beaches as food sources for crabs.Two-factor analysis of variance(ANOVA)shows that changes in mangrove species and age since restoration had different effects on crab burrow density.The effect of canopy cover was highly significant on crab burrow density.Conclusions:The results suggest that in the process of mangrove restoration the combined effects of mangrove stand age,canopy cover and other factors should be taken into account.This study further supports the findings of the future scientific research and practice on mangrove restoration and management measures.