摘要:

AbstractSoil, fungi, including species forming endomycorrhizae, appear to be important to pioneer plants colonizing coastal sand‐dunes in the subtropics. In three mobile dunes at Cooloola, Queensland, networks of fungal hyphae were very common in the surface 0‐20 cm of bare sand of the colonizing zones. These networks, consisting of long threads of hyphae, extend out into the bare sands from the roots of pioneer seedlings, most of which are endomycorrhizal. The fungi intermesh sand‐grains to form aggregates which appear to be an important factor in stabilizing these loose sands.The sands are dominantly quartz grains partly covered by thin sesquioxide coatings which contain some phosphorus. Phosphorus held by sesquioxide is generally regarded as being unavailable to most plants. However, the close attachment of hyphae to these coatings, the lack of alternative sources of phosphorus and the prominence of endomycorrhizal fungi are consistent with these fungi obtaining phosphorus from these surfaces. These fungi appear to be important in plant colonization of these dunes and could have appliction in revegetaton of disturbed

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01573.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractHabitat preferences of four species of small mammals were studied on a 7.5‐hectare trapping grid in a subalpine heathland/woodland complex on Mt William, western Victoria. Animals did not show strong spatial separation and differences in dispersion appeared to represent response to some feature of habitat. Floristic cues were good predictors of preference forRattus lutreolus, Antechinus swainsoniiandPseudomys fumeus.Structural factors might also be important forR. lutreolusandA. swainsonii.The entire grid was suboptimal forAntechinus stuartii.Pseudomys fumeuswas mycophagous during winter and, in the summer breeding season, principally ate seeds and bogong moths. Habitat preferences appear to reflect selection for those areas providing a year round source of high quality food rich in nitrogen. The transition period between the end of production of fungal sporocarps and prolific subalpine flower and seed production during summer may be particularly important as preferred areas provide fungi and seeds over longer periods, and food for bogong moths during their annual migratio

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01574.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThe smoky mouse (Pseudomys fumeus) undergoes large annual fluctuations in abundance, characterized by a dramatic decline in numbers just before the summer breeding season. The population on Mount William has two components which are differentially affected by this decline. The first, consisting of animals living in preferred microhabitat, have high breeding success and are unaffected by the decline. Females normally breed in two seasons, and in the second season breed earlier than first year females. The second component lives in non‐preferred microhabitat, is severely affected by the decline and shows high levels of fighting during the decline period. This difference may result from the lack of high quality food resources in non‐preferred microhabitat following the seasonal cessation of production of fungal sporocarps. The role of spatial and temporal heterogeneity in the availability of food resources in the population processes of small mammals is discus

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01575.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThere is little published information about coastal salt marshes in south‐western Australia, which are prominent in estuaries but absent from the high energy coastline. The zonation of the marshes of the Blackwood estuary resemble those in other parts of the world, in thatSarcocorniamarsh occurs near the mouth, followed by rush marsh, with sedges further upstream, suggesting that salinity is a prime determining factor.SpartinaandPhragmitesare absent. The most exensive marsh is theJuncus kraussiirush community which is invaded by the paperbark tree,Melaleuca cuticularis. The sedgeBaumea junceaforms a marsh community on the shores of the lower tidal river and a progression of species occurs with distance along the tidal river. A number of dynamic processes observed in these marshes are described and related to observations elsewhe

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01576.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractShrub invasion ofEucalyptus populneawoodland is of concern to the pastoral industry. As part of an ecosystem study, different analyses were used to identify spatial pattern and associations in the tree and shrub species, with the aim of identifying what factors were most influential on the ecosystem. The results suggested that there were no strong edaphic or topographic influences on the distribution of plants. The principal influence on the arrangement of trees and shrubs was the largeEucalyptustrees, which were randomly arranged, and the canopy of which covered 15% of the area. It is concluded that any disturbance of the largeEucalyptustrees would have intense effects on the whole ecosystem. Qualitative and quantitative measurements of the plant species in sample quadrats were subjected to a variety of pattern analyses including association analysis (DIVINF), correlation analysis, principal components analysis and several classification programs including POLYDIV and MULCLAS. A criticism of such analyses is that positive results are both inevitable and not subject to statistical proof, whilst their strength is that they can simplify complicated sets of data. In this case the patterns suggested by the results were visually apparent and no additional insights were achieved. The dangers inherent in relying on a single pattern analysis were revealed when the groups of quadrats produced by the different analyses were mapped. Even when the groupings derived from different analyses were based on a similar species content, their spatial arrangement was dissimilar.

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01577.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01578.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThe incidence of myrmecochory (plants providing inducements for ants to disperse their seeds) was studied in thirty‐eight plots on the West Head, New South Wales. The vegetation is made up of species from the temperate Australian flora which includes the largest known concentration of myrmecochores. Four plots with few myrmecochores either were frequently or permanently flooded, or were on fertile volcanic soil. Most plots were in well‐drained sites on infertile sandstone. An average of 30% of the species on each of these were certainly myrmecochores, accounting for an average of 15% of the total cover. Within this majority of plots, the incidence of myrmecochory was not related to slope, aspect or vegetation structure. Although many myrmecochores were widespread in distribution, the majority did not contribute heavily to cover of the stands where they occur

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01579.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThis ecological study of the Myall Lakes, a lagoon system on the New South Wales central coast, presents the physical setting and characteristics of the Lakes’catchments and relates these characteristics to the hydrochemical features of surface and subsurface waters. In turn these hydrochemical features have been related to the aquatic communities.It is suggested that the predominance of forest vegetation and stable soils in the Lakes’catchment has assisted in retaining these lakes in a generally undisturbed state.Fluctuations of salinity, turbidity and ionic concentrations in the lower part of the system are controlled by natural inputs of rainfall, run‐off and tidal flushings. However, Boolambayte Lake and particularly Myall Lake, the upper part of the system, appear to be isolated from these influences. The aquatic communities reflect these hydrochemical differences.The lack of flushing of waters in this upper part of the system, in Dirty Creek and to a lesser extent in the Myall River immediately upstream of the Broadwater, makes these areas particularly susceptible to pollution and eutrophication associated with increased develo

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01580.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractA long‐term study (1973‐9) was made of the intertidal floras of two headlands, one exposed to the ocean, the other in a bay. Many algal species varied erratically in frequency or occurrence from year to year, apparently due to local chance causes, but in some years many species showed reductions in frequency. In these years the changes in the flora appear to be associated with sand movements, which are possibly due to locally damaging storms. Recovery of the floras follows these depressions, but it is stressed that this recovery depends on the existence of a reservoir of spore‐producing plants which in turn depends on the maintenance of good water quality in the sea.The naturally occurring variations in floras are greater than are any induced by a low volume well‐treated sewerage outfall, except in the immediate area of the

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01581.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

AbstractThis is the first of a series of papers describing catenary patterns in central Australian sand‐ridge soils and vegetation, and observations and experiments designed to assess the interrelationships among them and the impact of fire. The aims and study area are described and previous literature reviewed briefly. Later papers will detail soil and vegetation patterns and discuss the relative importance of the dune‐swale gradients in soil texture, mobility, fertility and moisture status as controls and constraints on the vegetation, with reference to rainfall fluctuations and to changes in plant cover and environment at various time scales. These embody experimental studies on plant regeneration to suggest an overall model for the maintenance of the present open‐crested dune veget

ISSN:0307-692X    

DOI:10.1111/j.1442-9993.1981.tb01582.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY