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1.
The caprellidean fauna of Western Australia and Northern Territory, Australia, is investigated here. The study reports 26 species in 19 genera. Six new species (Aciconula australiensis n. sp., Caprella traudlae n. sp., Pseudaeginella vaderi n. sp., Orthoprotella nana n. sp., Pseudoprotella soela n. sp. and Pseudoprotomima grandimana n. sp.) are described as new for Science. Lateral view figures of all the species, together with a key to species level, are also provided.  相似文献   

2.

Background

Nitrogen-fixing legumes are key species in grassland ecosystems, as their ability to fix atmospheric nitrogen can facilitate neighboring plants. However, little is known about the fate of this legume effect in the face of extreme weather events, which are increasingly expected to occur.

Methods

Here, we examined experimentally how the presence of a legume modifies above-ground net primary production (ANPP) and nitrogen supply of neighboring non-legumes under annually recurrent pulsed drought and heavy rainfall events by comparing responses of three key species in European grassland versus without legume presence over 4 years.

Results

Legume presence facilitated community productivity of neighboring non-legumes under ambient weather conditions and also under experimental heavy rainfall. However, no facilitation of community productivity by the legume was found under experimental drought. Productivity of the three target species responded species-specifically to legume presence under different weather conditions: Holcus lanatus was facilitated only under control conditions, Plantago lanceolata was facilitated only under heavy rainfall, and Arrhenatherum elatius was facilitated irrespective of climate manipulations. The legume effects on δ 15N, leaf N concentration, and N uptake were also species-specific, yet irrespective of the climate manipulations. The data suggest that the missing legume effect on community productivity under the pulsed drought was rather caused by reduced N-uptake of the target species than by reduced N-fixation by the legume.

Conclusions

In contrast to heavy rain, the presence of a legume could not effectively buffer community ANPP against the negative effects of extreme drought events in an experimental temperate grassland. Facilitation also depends on the key species that are dominating a grassland community.  相似文献   

3.
Two new Keratella,rotatoria, from Australia   总被引:1,自引:1,他引:0  
Bruno Bērzinś 《Hydrobiologia》1963,21(3-4):380-383
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4.
纪念公园位于海泽布鲁克村,是一个地方公园,由于它在高速公路升级工程期间被用作工厂仓库和储存区,而受到严重的影响。 因此,在伍德福德村和海泽布鲁克村之间进行“纪念公园”的恢复成为升级大西部高速公路的重要任务。公园的恢复工程于2014年成功完成,并为道路基础设施项目如何通过创建高质量的公共开放空间而使当地居民受益提供了一个很好的范例。  相似文献   

5.
Two monotypic genera of coccosteoid eubrachythoracid arthrodires are described from the Upper Devonian Gogo Formation of Western Australia as Compagopiscis gen. nov. and Gogopiscis gen. nov. They are most closely related to Torosteus Gardiner & Miles, also from the Gogo Formation, and all three are placed in the family Plourdosteidae Vezina, 1990; Compagopiscis and Gogopiscis are jointly the sister-group of Torosteus.  相似文献   

6.
Mangrove zooplankton of North Queensland,Australia   总被引:2,自引:2,他引:0  
McKinnon  A. D.  Klumpp  D. W. 《Hydrobiologia》1997,348(1-3):127-143
Food consumption, growth, fish length distributions,population sizes and habitat use of the salmonids intwo lakes in the Høylandet area were studied in1986–89. The allopatric brown trout (Salmotrutta L.) in the tarn Røyrtjønna (27 ha) fed mainlyon organisms at the lake surface , crustaceanplankton, Trichoptera and Chironomidae. Only 5% ofthe trout reached an age of 6 years and a length of25 cm. Sexual maturation started at age 3 and a lengthof 14 cm. Through mark – recapture technique thenumber of trout >10 cm was estimated to 115 ha-1.Growth, fish length frequencies and sexualmaturation of the sympatric brown trout and Arcticcharr (Salvelinus alpinus (L.)) in LakeStorgrønningen (530 ha) were not much different. TheStorgrønningen charr fed chiefly on zooplankton whichby volume represented 33% for the trout. The foodconsumption of Storgrønningen trout was at maximum inJuly with 2.06 mg food (d.w.) per g live fish and forcharr in September with 1.26 mg food. The maximumsize-independent growth rate of trout was 5.2%day-1 in late June, and for charr 4.1%day-1 in late July. Seventy percent of theirseasonal growth took place before 15 August. The charrstayed mainly deeper than 3-4 m, at water temperatures<15 °C. Brown trout stayed mainly the littoralzone and in near surface water of the pelagic. Thenumber of pelagic charr was estimated hydroacusticallyto 50 ind. ha-1. The charr spawn in thelake. Mean numbers of juvenile trout in the twolargest tributaries were 26 and 48 per 100 m2.Their annual length increment was 2.8–3.4 cm. Noindication of acidification or other human inducedimpacts were found. The lakes and their tributariesrepresent complex aquatic systems, representative forpristine oligotrophic Norwegian lowland lakes.John W. Jensen died shortly after easter in 1996  相似文献   

7.
McKinnon  A. D.  Klumpp  D. W. 《Hydrobiologia》1997,362(1-3):145-160
Measurements of plankton community structure and trophic resourcespotentially available to planktonic copepods were made in the mangroveestuaries of six rivers in Northeastern Australia. The Pascoe, Claudie,Lockhart, McIvor and Daintree Rivers represent wet tropical systems on CapeYork, whereas the Haughton River estuary has restricted freshwater inflowbecause of a drier climate and freshwater diversion for agriculture. TheHaughton River was sampled approximately monthly between October 1992 andMay 1994, and had a mean abundance of zooplankton >37 μm of 200l−1 (range 60–500 l−1). The Cape Yorkrivers were sampled infrequently, and zooplankton abundances ranged between0.4 and 1400 l−1. The zooplankton of all rivers was dominatedby copepods, particularly representatives of the genus Oithona which werecharacteristic of a distinct mangrove fauna. Physical forcing influencedthe zooplankton of mangrove estuaries much more than the measured biologicalvariables. The water column was characterised by high concentrations ofparticulate matter, up to 3.3 mg l−1 C and 1.1 mgl−1 N, of low food quality (as indicated by the C:N ratio).Phytoplankton biomass (as chlorophyll a) in all six rivers was on averagefour-fold greater than in neighbouring coastal waters (1.1–12.6μg l−1), and 25% of this chlorophyll a wasderived from cells >10 μm, and thus potentially available tocopepods. The degree of mixing, determined by the combination of tidal stateand the extent of freshwater input, appears to drive both the quantity andquality of particulate material available to higher consumers and thedistribution of zooplankton communities within mangrove estuaries. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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10.
Alcoa World Alumina Australia mines bauxite under lease agreements with the Government of Western Australia. The leases lie in the Darling Range to the east of Perth, the capital and major population center. In addition to bauxite and other mineral ores, the Darling Range is a major potable water source and harbors a species-rich forest dominated by Jarrah (Eucalyptus marginata), a significant commercial timber. Conservation and recreation are important land uses in the region. Social and political pressures have led to stringent governmental requirements for restoration. In addition, a summer drought period, a soil deficient in most nutrients, water management challenges, an introduced disease, caused by Phytophthora cinnamomi Rands, and a post-mining ecosystem that must be conducive to the prescribed burning management of the region pose significant challenges to successful restoration. Alcoa presently mines and restores approximately 550 ha per annum. Although the “footprint” at the end of the life of the mining operations represents only about 4% of the total forest estate, Alcoa is committed to restoring the forest values of the region of all lands impacted by mining. The major objective of restoration is to enhance or maintain forest values by restoring habitat and structural characteristics of the native forest environment. Completion criteria for Alcoa’s mine restoration have been developed. The original Alcoa mine at Jarrahdale has been rehabilitated, and in 2005, a 975-ha area received a “certificate of completion” and was returned to the management control of the State of Western Australia.  相似文献   

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15.
Phosphorus speciation in Myall Lake sediment, NSW, Australia   总被引:1,自引:0,他引:1  
The amount of phosphorus and its fractions in the sediment of Lake Myall, NSW, Australia, was assessed using a sequential extraction technique. Five sedimentary phosphorus reservoirs were measured, namely loosely sorbed phosphorus (NH4Cl–P), iron associated phosphorus (BD–P), calcium bound phosphorus (HCl–P), metal oxide bound phosphorus (NaOH–P) and residual phosphorus (organic and refractory P, Res-P). Samples were taken from the deep and shallow sites of the lake. During the analysis, the average concentrations of each fraction of phosphorus was calculated. The results depicted that the total phosphorus (TP) content and chemically extractable phosphorus in both fine and coarse sediment fractions from the deep sites of the lake were significantly higher than those of the shallow sites, except for HCl–P extracted from the fine sediment fraction. Sediment TP was also strongly and positively correlated to sediment Fe. The phosphorus in the sediment mainly consisted of BD–P and Res-P, while NH4Cl–P and HCl–P only contributed a minor part. The rank order of the different phosphorus extracts was similar for the two sites, namely Residual-P > BD–P > NaOH–P > HCl–P > NH4Cl–P.  相似文献   

16.
《Journal of bryology》2013,35(2):213-227
Abstract

Two new species of Acaulon, A. chrysacanthum and A. leucochaete are characterized by lamellae on the adaxial surface of the nerve and are placed in a new subgenus, Alaticosta. Acaulon chrysacanthum has leaves with the nerve excurrent as a stout reddish-gold arista, and brown papillose spores, 30–35 µm in diameter. Acaulon leucochaete has the nerve excurrent as a long colourless flexuose hair point and buff-coloured spores, more finely papillose and 23–25 µm in diameter. Both are species of semi-arid areas usually growing on red sandy soil in mallee scrub.  相似文献   

17.
New durophagous arthrodires from Gogo, Western Australia   总被引:1,自引:0,他引:1  
Three new monotypic genera of eubrachythorarid arthrodires with crushing toothplates are described from the Upper Devonian Gogo Formation of Western Australia as Bruntonichthys multidens gen. et sp. nov., Bullerichthysfascidens gen. et sp. nov. and Kendrickkhthys cavemosus gen. et sp. nov. Their structure and relationships are discussed within the framework provided by a sketch cladogram. All three are interchangeable with Coccosteus spp. but their phylogenetic relationships are not known in any detail. However, Kendrickkhthys does appear to be immediately related to Dinomylostoma from North America.  相似文献   

18.
Human remains of a male individual from Cossack, northwestern Australia are described. Absolute dating is not possible but site geomorphology restricts the upper limit to 6500 B.P. Morphologically and metrically the skull differs from those of recent Western Australian male Aborigines, but it is very similar to that of Kow Swamp I and others included in the “robust” prehistoric Australian Aboriginal group (Thorne, 1977). The specimen is important as indicating the widespread nature and probable recency of a large, robust Australian Aboriginal population demonstrably different to recent populations.  相似文献   

19.
《Journal of bryology》2013,35(3):359-364
Abstract

Fissidens traversii, a new species from Queenslahd, Australia, is characterised by the rounded leaf apex, costa papillose and finishing short of the apex, mamillose, multipapillose cells, short dorsal lamina and vaginant laminae (which usually have a marginal strip of transversely elongated calls in the lower half), reaching almost to the apex of the leaf.  相似文献   

20.
Australia     
《BMJ (Clinical research ed.)》1930,2(3632):264-265
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