Fungi in Ecosystem Processes | John Dighton | Taylor & Francis eBooks,

ABSTRACT

Adopting the novel approach of viewing the role of fungi from the perspective of ecosystem functions, this book examines the importance of fungi in soil formation, plant primary production, sustenance of secondary producers, and regulation of plant and animal populations and communities. This volume emphasizes the idea that fungi are not alone in the regulation of these processes. It addresses the main processes occurring in ecosystems and showing where and how fungi are critical, and enables readers to gain a better understanding of the role of fungi in shaping ecosystems. "Fungi in Ecosystem Processes" considers the negative impact of fungi on faunal productivity and includes more than 1200 citations.

TABLE OF CONTENTS

chapter 1|7 pages

Introduction

chapter |3 pages

FIGURE 1.1 Life history strategies as applied to fungi, contrasting the r-K concept of Pianka (1970) with the R– C–S strategy of Grime (1977; 1979).

chapter |3 pages

FIGURE 1.3 Representation of the exploitation of rich (right) and poor (left) resources by fungal hyphae. The fast, diffuse growth in the poor resource allows for rapid mycelial extension at minimal energetic cost to the fungus. The slow, dense growth in the rich resource allows for maximal exploitation of the resources within the substrate by the mycelium. Energy is expended to produce the extensive hyphal network to maximize the fungal surface area for the excretion of enzymes and uptake of nutrients and carbon.

chapter |4 pages

into the soil inorganic nutrient pool. Nutrients are immobilized into recalcitrant organic resources (such as the log on the right) and into fungal biomass. Here there can be both temporal and spatial redistribution of nutrients within the fungus and among resources utilized by the fungi. Mycorrhizae on plant roots aid the uptake of mineral nutrients into the plant, help to defined the plant against root pathogens, and may effect decomposition of organic residues. Both fungal hyphae and fruiting structures (represented by mushrooms) are a food source for grazing animals, thus influencing the fitness of individuals and regulating animal populations. Source: Adapted from Dighton and Boddy (1989).

chapter |1 pages

pathogens, which directly utilize plant photosynthates. The right side of the model represents the decomposition cycle, utilizing dead plant and animal parts. Open arrows at the top indicate feedback effects on photosynthesis (plant fitness).

chapter |6 pages

FIGURE 1.6 Actual number of fungal species known (69,000) and potential total number of fungal species in the world (3,004,800) based on new species to be found associated with yet to be discovered plants and insects. Source: Data from Hawksworth (1991).

chapter 2|3 pages

Fungi and Primary Productivity: Making Nutrients Available

chapter |14 pages

TABLE 2.2 Taxonomic Diversity of Lichen Mycobionts and Photobionts

chapter |3 pages

their relative contribution to the development of water-stable soil aggregates. Arrows indicate path coefficients, where * is significant at P<0.05, P<0.01, and *P<.001. Source: After Miller and Jastrow (1990).

chapter |1 pages

FIGURE 2.3 Diagrammatic representation of the decomposition of plant residues by fungal enzymes, the mineralization of inorganic nutrients to the soil nutrient pool, and the immobilization of nutrients into fungal biomass. At time A, the fungal hyphae colonize the plant resource, secrete extracellular enzymes (arrows within the resource), and mineralize nutrients

chapter |2 pages

from the organic resources in the plant litter. Much of the mineralized nutrient is immobilized by the fungal biomass and converted to growth; however, the system is leaky and some mineralized nutrient is lost to the soil nutrient pool. As time continues, the plant resource is utilized and more nutrient accumulates in both fungal biomass and the soil nutrient pool. The latter accumulation in soil gives rise to soil fertility as it is available for plant growth.

chapter |2 pages

FIGURE 2.4 Maximum estimates of fungal hyphal length (open bars) and fungal biomass (hatched bars) in soils from a range of ecosystems. Source: From Kjøller and Struwe (1982).

chapter |21 pages

TABLE 2.12 Relative Contribution of Woody Debris and Nonwoody Litter to the Forest Floor in Temperate Woodland Ecosystems

chapter |1 pages

development of fungal communities colonizing alder leaf litter in streams. Source: Data derived from Gessner et al. (1993).

chapter |1 pages

cordgrass (Spartina alterniflora) in a salt marsh system, showing the proportion of carbon lost to dissolved organic matter (DOM), fine participate organic matter (FPOM), and incorporation into bacterial and fungal biomass. Source: Modified from Gessner et al. (1997).

chapter |10 pages

a variety of plant resources in an variety of aquatic ecosystems. The community structure separates significantly along axis 1, where the tree leaf litter communities show similarity between each other but are different from communities developed on wood and grass leaves, which lie to the left of PCA axis 1 and are separated from each other along PCA axis 2. Source: Data from Gulis (2001).

chapter 3|4 pages

Fungi and Primary Productivity: Plant Growth and Carbon Fixation

chapter |1 pages

Solid bars represent relative growth rate, hatched bars represents the relative growth rate over a 10 week interval. Data from Cooper and Wookey (2001).

chapter |10 pages

FIGURE 3.3 Density of the lichen Lobaria oregana colonizing rough or smooth experimental branches located in clearcut, young and old growth Douglas fir forest stands. Data from Sillett et al. (2000).

chapter |1 pages

tree name) of a selection of tree species and heather (Calluna vulgaris), the rate of decomposition of that plant litter and the pH of soil. (Redrawn from Read, 1991.)

chapter |1 pages

quality, its rate of decompositon and the enzxyme competence of the mycorrhizal community. (Modified from Read, 1991 and Dighton and Mason, 1985.)

chapter |9 pages

ericaceous plant Vaccimium macrocarpon in the presence (M) or absence (NM) of ericoid mycorrhizal inoculum when provided with orthophosphate (Ortho-P) or nutrients supplied in the form of nuclei. Data from Myers and Leake (1996).

chapter |3 pages

uptake, driven by the saprotrophic fungal community (thin arrows). The affect of mycorrhizae are shown by thick arrows and the dotted arrows showing mycorrhizal enzyme activity, exudation of carbohydrates to stimulate synergistic activities with bacteria (PGPBs and helper bacteria) and the secretion of rock dissolving organic acids. L, C and K represent leaching, comminution and catabolism, respectively. Redrawn from Vogt et al. (1991).

chapter |4 pages

hyphae, and 3a reducing the threshold concentration of P required to permit transfer of P across the plant cell membrane. Adapted from Bolan (1991) with kind permission of kluwer Academic Publishers. TABLE 3.14 Production of Organic Acids in the Rhizosphere of Calcifuge and Calcicole Plant Species Showing the Adaptation of Calcicoles in Order to Solubilize Phosphate and Essential Heavy Metals

chapter |4 pages

plants (open bars) and plants treated with a soil application of benomyl (hatched bars) to reduce the arbusculr mycorrhizal colonization of the roots. Pairs of bars sharing the same letter are not significantly different from each other. Data from Merryweather and Fitter (1996).

chapter |6 pages

TABLE 3.15 Plant Biomass (g Dry Weight) of Gmelina Seedlings Inoculated in the Seed or at the Seedlings Stage with the Saprotrophic Fungus Chaetomium bostrychoides Before and After a Drought Event

chapter |9 pages

FIGURE 3.23 Effect of ectomycorrhizal species diversity on shoot and root growth of birch seedlings when inoculated with a random mixture of mycorrhizal fungal species, selected from a species pool. Data from Baxter and Dighton (2001).

chapter |1 pages

FIGURE 3.26 Arbuscular mycorrhizal colonization of roots of the emergent aquatic plant Lythrum salicarina in hydroponic sand culture at different levels of P supply. Data from White and Charvat (1999).

chapter |2 pages

FIGURE 3.27 Total plant mass (left) and root:shoot ratio (right) of the emergent aquatic plant Lythrum salicarina with (solid bars) and without (open bars) arbuscular mycorrhizal inoculum grown in hydroponic sand culture at different levels of P supply. Data from White and Charvat (1999).

chapter |2 pages

FIGURE 3.28 Effect of arbuscular mycorrhizal infection on shoot nitrogen content of plants of Spartina cynosuroides. Experimental conditions were: mycorrhizal infection (clear bars; N=un-inoculated, Y=inoculated) added phosphorus (hatched bars; H=3.10 mg PO -P/l, L=0.31 mg PO-P/l) water salinity (solid bars; F=no salt added, S=7 ppt salt) tidal inundation (stippled bars; B=bottom level, M=middle level, U=upper level). Data from McHugh and Dighton (unpublished).

chapter |6 pages

FIGURE 3.29 Ratio between P in mycorrhizal plants over P in non-

chapter |4 pages

FIGURE 3.32 Number of plants and plant biomass of Kummerowia stipulacea in the presence and absence of the plant pathogen Pythium in field soil, soil sterilized by microwaving and sterile soil amended with fungal pathogen spores (Sp). Data from Alexander and Mihail (2000).

chapter |21 pages

TABLE 3.23 Interactions Between Two Root Pathogenic Fungi (Fusarium solani 1, Rhizoctonia solani 2) and an Arbuscular Mycorrhiza (Glomus mosseae) on Plant Growth and Fecundity of Peanut Plants, Showing Alleviation of the Detrimental Effects of the Pathogen by the Mycorrhizae

chapter 4|5 pages

Fungi, Secondary Productivity, and Other Fungal-Faunal Interactions

chapter |12 pages

FIGURE 4.1 Percentage contribution of fungi to the annual diet of nine small mammal species in the Pacific Northwest. Source: Data from Fogel and Trappe (1978). TABLE 4.3 Chemical Composition of Fungi in Comparison with Plant Parts and Meat

chapter |1 pages

FIGURE 4.2 The effect of collembolan density on arbuscular mycorrhizal spore density and colonization of maize roots by mycorrhizae. Source: Data from Bakonyi et al. (2002).

chapter |2 pages

FIGURE 4.3 Numbers of eggs produced and hatched from first generation collembola (Folsomia candida) when fed upon a variety of arbuscular mycorrhizal fungi. Source: Data from Klironomos et al. (1999).

chapter |2 pages

FIGURE 4.4 Principle coordinate analysis of ectomycorrhizae in protozoan species space, showing the difference in protozoan community structure of different ectomycorrhizal fungal species on roots of ponderosa pine. Four groupings appear from this analysis with similar protozoan communities on group 1 [Rhizopogon subcaerulenscens (Rs), R. ellenae (Re), and R. truncates (Rt)] from group 2 [R. arctostaphylii (Ra), R. smithii (Rsm), and R. flavofibrillosus (Rf)], from group 3 [R. vulgaris (Rvu), R. rubescens (Rr), Thelephora terrestris (Thel), and Mycelium radicis atrovirens (MRA)] from the outlier R. occidentalis (Ro). Source: The data have been reworked from Ingham and Massicotte (1994), and the first two axes account for 23% and 18.2% of the variation, respectively.

chapter |1 pages

FIGURE 4.5 Hierachical feeding preference of the collembola, Folsomia candida on fungi as determined by mean fecal number produced by collembola and percentage consumption of the mycelial colony provided as a food source. Source: Data from Shaw (1988).

chapter |4 pages

FIGURE 4.6 Changes in feeding behavior of the collembola Proistoma minuta over time when offered a choice of food items of the ectomycorrhizal fungi Alpova olicaeotinctus, Melanogaster tuberiformis, an unknown isolate M-40, or PDA agar in pairwise combinations. Source: Data from Schultz (1991).

chapter |3 pages

TABLE 4.13 Viability of Fungal Spores After Passage Through the Gut of Two Earthworm Species

chapter |1 pages

TABLE 4.16 The Effect of Inoculation of Seedlings of Ponderosa Pine with Feces of Tassel-Eared Squirrels and Fruit Bodies of Hypogeous Fungi

chapter |4 pages

TABLE 4.17 Number of Arbuscular Mycorrhizal Spores Found in the Feces of Spiny Rats in Neotropical Forests of Central America

chapter |2 pages

FIGURE 4.11 Concentrations of nitrogen (solid bars) and phosphorus (hatched bars) in phloem of Pinus taeda trees with or without infestation of Dendroctonius frontalis and its associated mycangial fungi. Blue stain is where the bark is also infected with the blue stain fungus Ophiostoma minus, which inhibits the growth of the mycangial fungi. Source: Data from Ayres et al. (2000).

chapter |2 pages

FIGURE 4.12 Interactions among the bark beetle, Ips cembrae, the wood wasp, Urocerus gigas, and the two larch fungal pathogenic fungi, Ceratocystis lariciola and Amylostereum chailletti, showing how the severity of the diseases depends on interactions between the two insects. Source: From Redfern (1989).

chapter |2 pages

appears to be with insect diseases, which are mainly fungal.

chapter |14 pages

FIGURE 4.14 Percentage of red-eyed treefrog egg mortality in laboratory-cultured egg masses when infected by a pure culture of an ascomyete fungus inoculm introduced by contaminated eggs, and from a natural population. Source: Data from Warkentin et al. (2001).

chapter 5|4 pages

Fungi and Population and Community Regulation

chapter |2 pages

TABLE 5.2 Effects of Mycorrhizal Colonization on the Growth and Nutrient Content of Lodgepole Pine (Pinus contorta) Seedlings by the Dark-Septate Fungus Phialocephalala fortinii in the Presence and Absence of Added Organic Matter and Nitrogen to Lyman Glacier Forefront Soil

chapter |2 pages

colonization and persistence potential of the fungi. Source: From Hart et al. (2001). FIGURE 5.3 Effect of seed inoculation with Chaetomium bostrychodes on the germination of Gmelina arborea seeds. Source: Data from Osonubi et al. (1990).

chapter |3 pages

TABLE 5.4 Responses of Different Plant Families to Arbuscular Mycorrhizal Infection Showing a Continuum of Responses from Positive at One End to Negative at the Other

chapter |1 pages

arbuscular mycorrhizae. Source: Data from Streitwolf-Engel et al. (2001).

chapter |7 pages

FIGURE 5.6 Models of the response between arbuscular mycorrhizal plants to mycorrhizal infection and soil phosphorus availability. Graph a depicts each plant species in the community responding in the same way, with a reduction of mycorrhizal colonization of roots with increasing P supply. In this situation, the net ecosystem effect is for a general reduction in mycorrhizal associations. Graph b depicts a variable response of each plant species in the community, resulting in a net lack of mycorrhizal response throughout the ecosystem. Source: From Allison and Goldberg (2002).

chapter |3 pages

FIGURE 5.9 Changes in the relative basal area of Douglas fir trees in relation to late successional trees (A) or shrubs (B) in the H.J.Andrews forest as a result of the root-rotting fungal pathogen Phelliunus weirii. Changes are indicated by arrows showing trends in response from plants outside infection centers (solid symbols) to areas within infection centers (open symbols). Source: Data modified from Holah et al. (1997).

chapter |3 pages

larici-populina. Saprotroph conidia incubated before uredinospores added (open bar), conidia, and uredospores as a mixed inoculum (solid bar) and uredinospores added before conidia (hatched bar) compared to infection without saprotroph (control). Source: Data from Omar and Heather (1979).

chapter |1 pages

TABLE 5.6 Effect of Inoculation of Chestnut Seedlings (Castanea sativa) with Ectomycorrhiza Against the Effects of the Chestnut Ink Stain Fungal Pathogen Phytopthora cambivora

chapter |3 pages

TABLE 5.7 Growth and Disease Status of Cotton Plants Grown in Association with the Wilt Pathogen Verticillium dahliae, Arbuscular Mycorrhizae, and Combinations of the Two

chapter |2 pages

Removal of any variable significantly reduced the model fit. Source: Data from Packer and Clay (2000) reprinted by permission from Nature (2000) 404:278–281 Macmillan Publisher Ltd.

chapter |1 pages

TABLE 5.10 Survival of Seedling Tropical Ectomycorrhizal Trees After 16 Months of Growth Under the Canopy of Conspecific Adults at Low and High Stem Density

chapter |3 pages

TABLE 5.11 The Influence of Fungal Endophytes of Grasses in Reducing Damage by Animals

chapter |1 pages

FIGURE 5.16 Hypothesized relationship between the evolution of endophytic infection of plants and the intensity of herbivory over time. Source: From Clay (1997). FIGURE 5.17 Influence of infection of the thistle Cirsium arvense with the plant pathogenic fungus Phoma destructiva on (a) choice of leaf for

chapter |4 pages

feeding, (b) leaf area consume, (c) larval development time, and (d) pupal weight of the herbiverous beetle Cassida rubiginosa. Source: Data from Kruess (2002).

chapter |3 pages

of spores of phylloplane and endophytic fungi (upper graph) and pupal survival of the leafminer Cameraria in the presence of phylloplane and endophytic fungi (lower graph). Source: Data from Faeth and Hammon (1997).

chapter |2 pages

FIGURE 5.20 The effect of arbuscular mycorrhizal inoculation on the population of the root burrowing nematode Radopholus similis. Source: Data from Elsen et al. (2001).

chapter |1 pages

TABLE 5.16 Seedling Plant Height and Survival of Three Tree Species in a Tree Nursery in Which the Soil Surface was Left Bare or Had been Covered with the Foliose Lichen Cladonia alpestris Collected from a Surrounding Forest

chapter |13 pages

TABLE 5.17 Allelopathic Effect of the Lichen Cladonia spp. on Tree Species

chapter 6|3 pages

Fungal Interactions with Humans

chapter |2 pages

metal availability, leading to root and mycorrhizal damage and increased fertility from nitrogen sources, reducing the dependency of the plant on mycorrhizae. The third model represents damage to foliage and loss of photosynthetic capacity. This reduces the carbohydrate flux to roots, resulting in a loss of mycorrhizal diversity and function. Source: After Dighton and Jansen (1991).

chapter |3 pages

FIGURE 6.2 Arbuscular mycorrhizal development in sugar maple under the influence of elevated atmospheric ozone. Ozone level 1=X, 1=Y, 3=Z. Source: After Duckmanton and Widden (1994).

chapter |10 pages

FIGURE 6.3 PC analysis of the effects of added nitrogen fertilizer, simulating atmospheric nitrogen deposition in a NITREX experiment in Sweden. The top two analyses are treatment plots in ectomycorrhizal fruit body species space, showing the nitrogen-treated plots having a different community structure than the untreated control plots. The third analysis is similar, but uses mycorrhizal community structure based on molecular identification of root tips. This latter analysis shows less difference in mycorrhizal community structure between unfertilized and fertilized plots. Source: Data compiled from Brandrud (1995) and Jonsson (1998).

chapter |1 pages

pollutant movement among components, but the thick arrow represents a direct effect of the pollutant on the fungi. Source: After Wainwright and Gadd (1997).

chapter |3 pages

TABLE 6.4 Ranges of Metal Uptake Capacities of a Variety of Microfungal Mycelial and Yeast Species that Could be Used in Industrial Processes

chapter |5 pages

TABLE 6.5 Relative Accumulation of Mercury in Fungal Fruit Bodies in Relation to Soil Humus Concentrations

chapter |1 pages

concentrations of lead. Source: After Chappelka et al. (1991).

chapter |9 pages

ectomycorrhizal fungi (left) and the proportion of lead translocated to agar, distant from the site of lead addition, through the fungal mycelium. Source: Data from Vodnik et al. (1998).

chapter |11 pages

TABLE 6.14 Pre- and Post-Chernobyl Radiation Levels in the Environment and in Mushrooms

chapter |1 pages

FIGURE 6.12 Model of the possible effects of increased atmospheric CO and elevated temperature on the tree-ectomycorrhizal symbiosis. The top model indicated the diversity and function of mycorrhizae in an elevated CO scenario. Increased

chapter |6 pages

decomposition and nutrient mineralization, leading to a reduced host dependency on the mycorrhizal symbiosis. In scenario C, the change in leaf litter chemistry (enhanced nitrogen content) increases resource quality, and the mycorrhizal fungi have to compete with the saprotrophic community for access to mineralized nutrients by increasing diversity and extraradical hyphal exploitation of soil. Source: Adapted from Dighton and Jansen (1991).

chapter |2 pages

FIGURE 6.15 Effects of increasing atmospheric CO on the growth and lateral root formation of oak trees in the presence (+) and absence (−) of Laccaria laccata mycorrhizae. Source: After Seegmüller and Rennenberg (1994) with kind permission of Kluwer Academic Publishers.

chapter |2 pages

from the root surface. Source: Data from Sanders et al. (1998).

chapter |1 pages

FIGURE 6.17 Comparison between the proportion of Suillus spp. and other ectomycorrhizal fruit bodies in radiata pine plantations in Ecuador and California, the overall diversity of mycorrhizal associations between countries and the carbon fixed in mushroom production. Source: Data from Chapela et al. (2001).

chapter |19 pages

TABLE 6.22 Changes in Land Use in England and Wales During 6 Years (1984–1990), the Calculated Loss of Soil Carbon, and the Predicated Loss by the Year 2020

chapter 7|1 pages

Synopsis and Outlook to the Future

chapter |2 pages

FIGURE 7.1 Concepts of hierarchy and scale in ecosystems. The relationship between scales (indicated by double-headed arrows) is important in assessing the impact of function at a lower scale on the processes at higher scales. Source: From Friese et al. (1997).

chapter |2 pages

FIGURE 7.2 An ecosystem as seen from the point of view of a modeler. Here only the components of a system are necessary for explaining processes. Dots represent real or imaginary organisms. The large upward arrow represents the average activity value for all organisms in the ecosystem. Arrows from species indicate the contribution of each species to the whole ecosystem activity and represents functional groups, enzyme activity, etc. External environmental forces are represented by the box and arrow on the right. Source: Modified from Andrén et al. (1999).

chapter |4 pages

ecosystem function as diversity increases. Type B response shows saturation of the ecosystem response before maximal species diversity is attained. Source: Adapted from Schwartz et al. (2000).

chapter |14 pages

TABLE 7.3 Estimates of the Total Number of Fungi in the World