New insights into the mycorrhizal status of Cyperaceae from ultramafic soils in New Caledonia

2011 ◽  
Vol 57 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Alexandre Lagrange ◽  
Marc Ducousso ◽  
Philippe Jourand ◽  
Clarisse Majorel ◽  
Hamid Amir
Keyword(s):  
New Caledonia ◽  
Metal Tolerance ◽  
Hot Spot ◽  
Nickel Content ◽  
Arbuscular Mycorrhizas ◽  
Molecular Evidence ◽  
Ultramafic Soils ◽  
Plant Tolerance ◽  
Positive Role ◽  
Mycorrhizal Status

In New Caledonia, a hot spot of biodiversity, plants from the Cyperaceae family are mostly endemic and considered pioneers of the nickel-rich natural serpentine ecosystem. The aim of the study was to highlight the mycorrhizal status of these Cyperaceae and to bring new insights into the role of this symbiosis in plant tolerance to ultramafic soils. Nine Cyperaceae species were studied and presented evidence of root colonization by arbuscular mycorrhizas (AMs), with frequencies ranging from 8% to 57%. The highest level of AM colonization was observed in plants from the endemic dominant genus Costularia . Molecular evidence demonstrated the presence of Glomus sp. inside the roots. In a controlled greenhouse assay, AM inoculation of Costularia comosa grown under ultramafic conditions significantly enhanced plant growth, with an increase in biomass by up to 2.4-fold for shoots and 1.2-fold for roots, and also reduced nickel content in roots by 2.5-fold, as compared with the controls. All these data support our hypotheses (i) that a relationship exists between the mycorrhizal status of Cyperaceae and their habitat, and (ii) that AM have a positive role in plant tolerance to ultramafic soils (mineral nutrition and metal tolerance), suggesting the use of these pioneer plants with AM management as potential tools for nickel mine site rehabilitation in New Caledonia.

scholarly journals Remote sensing of <i>Trichodesmium</i> spp. mats in the western tropical South Pacific

2018 ◽  
Vol 15 (16) ◽  
pp. 5203-5219 ◽  
Author(s):  
Guillaume Rousset ◽  
Florian De Boissieu ◽  
Christophe E. Menkes ◽  
Jérôme Lefèvre ◽  
Robert Frouin ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Large Scale ◽  
New Caledonia ◽  
Hot Spot ◽  
Regional Scale ◽  
Atmospheric Correction ◽  
South Pacific ◽  
Aggregation Processes ◽  
Modis Imagery ◽  
Generate Surface

Abstract. Trichodesmium is the major nitrogen-fixing species in the western tropical South Pacific (WTSP) region, a hot spot of diazotrophy. Due to the paucity of in situ observations, remote-sensing methods for detecting Trichodesmium presence on a large scale have been investigated to assess the regional-to-global impact of this organism on primary production and carbon cycling. A number of algorithms have been developed to identify Trichodesmium surface blooms from space, but determining with confidence their accuracy has been difficult, chiefly because of the scarcity of sea-truth information at the time of satellite overpass. Here, we use a series of new cruises as well as airborne surveys over the WTSP to evaluate their ability to detect Trichodesmium surface blooms in the satellite imagery. The evaluation, performed on MODIS data at 250 m and 1 km resolution acquired over the region, shows limitations due to spatial resolution, clouds, and atmospheric correction. A new satellite-based algorithm is designed to alleviate some of these limitations, by exploiting optimally spectral features in the atmospherically corrected reflectance at 531, 645, 678, 748, and 869 nm. This algorithm outperforms former ones near clouds, limiting false positive detection and allowing regional-scale automation. Compared with observations, 80 % of the detected mats are within a 2 km range, demonstrating the good statistical skill of the new algorithm. Application to MODIS imagery acquired during the February-March 2015 OUTPACE campaign reveals the presence of surface blooms northwest and east of New Caledonia and near 20∘ S–172∘ W in qualitative agreement with measured nitrogen fixation rates. Improving Trichodesmium detection requires measuring ocean color at higher spectral and spatial (<250 m) resolution than MODIS, taking into account environment properties (e.g., wind, sea surface temperature), fluorescence, and spatial structure of filaments, and a better understanding of Trichodesmium dynamics, including aggregation processes to generate surface mats. Such sub-mesoscale aggregation processes for Trichodesmium are yet to be understood.

Riethia (Kieffer 1917) (Diptera: Chironomidae) revised for the Austro-Pacific region

Zootaxa ◽  
2019 ◽  
Vol 4646 (3) ◽  
pp. 461-500 ◽  
Author(s):  
PETER S. CRANSTON
Keyword(s):  
New Zealand ◽  
Adult Male ◽  
New Caledonia ◽  
Molecular Data ◽  
Molecular Evidence ◽  
Pacific Region ◽  
South American Species ◽  
Standing Waters ◽  
Flowing Waters ◽  
Male Pupa

Riethia Kieffer, known previously from New Zealand for a species stated to be also in Australia plus several Australian and South American species, is revised for the Austro-Pacific region. The three previously-described Australian species Riethia stictoptera Kieffer (the genotype), Riethia cinctipes Freeman and Riethia plumosa Freeman are distinct and valid, and are redescribed in all stages. In contrast, Riethia zeylandica Freeman now is restricted to New Zealand: Australian specimens previously allocated to R. zeylandica belong to several new species recognised on morphology of adult male, pupa and larva, with guidance from molecular data. Most belong to a widespread eastern Australian Riethia azeylandica sp. n.: others are allocated to Riethia hamodivisa sp. n., Riethia paluma sp. n., Riethia phengari sp. n. and Riethia queenslandensis sp. n., each with a more restricted range. From Western Australia three species, Riethia donedwardi sp. n., Riethia noongar sp. n. and Riethia wazeylandica sp. n., are described as new from adult male, pupa and larva. Riethia kakadu sp. n. is described from the monsoonal tropics of Northern Territory from the adult male and tentatively associated pupa. From New Caledonia a reared species is described as Riethia neocaledonica sp. n.. Illustrated identification keys are provided for the males, pupae and larvae. Unassociated larvae that key to reared described species are excluded from type status, and based on morphology and molecular evidence three unreared larval types, ‘A’, ‘B’ and ‘C’, are also described and keyed. Previously reported molecular vouchers are reviewed, and certain Genbank accessions re-identified. Extensive data shows Riethia are distributed almost throughout Australia from standing and flowing waters, from tropics and subtropics to cool temperate Tasmania, but probably only in permanent and standing waters. The immature stages of several taxa can co-occur: as many as four can be found simultaneously in one site. Terminology of the volsellae of the male genitalia and the dorsal head and maxilla of the larva is reviewed. 

Mechanisms Underlying Heavy Metal Tolerance in Arbuscular Mycorrhizas

2008 ◽  
pp. 107-122 ◽  
Author(s):  
Manuel González-Guerrero ◽  
Karim Benabdellah ◽  
Nuria Ferrol ◽  
Concepción Azcón-Aguilar
Keyword(s):  
Heavy Metal ◽  
Metal Tolerance ◽  
Heavy Metal Tolerance ◽  
Arbuscular Mycorrhizas

Neither a buccinid nor a turrid: A new family of deep-sea snails for Belomitra P. Fischer, 1883 (Mollusca, Neogastropoda), with a review of Recent Indo-Pacific species

Zootaxa ◽  
2012 ◽  
Vol 3496 (1) ◽  
pp. 1 ◽  
Author(s):  
YURI I. KANTOR ◽  
NICOLAS PUILLANDRE ◽  
AUDREY RIVASSEAU ◽  
PHILIPPE BOUCHET
Keyword(s):  
Deep Water ◽  
New Caledonia ◽  
Solomon Islands ◽  
Valid Species ◽  
Molecular Evidence ◽  
Society Islands ◽  
Sulu Sea ◽  
Anal Ysis ◽  
New Family ◽  
Pacific Species

The new family Belomitridae is established for the deep-water buccinoid genus Belomitra P. Fischer, 1883, based onmorphological (shell and radulae) and molecular evidence. The rachiglossate radula is uniquely characterized by amulticuspid rachidian and lateral teeth with very long narrow bases and two small cusps closer to tip. Molecular anal-ysis of a reduced set of Buccinoidea did not resolve the group as a clade, but shows that Belomitridae forms a wellsupported clade within Buccinoidea. Species of Belomitra have adult sizes in the 7–53 mm range; they live in deepwater, mostly in the 500–2,000 meters range, at low and mid latitudes. Eleven valid species described from the Indo-Pacific were originally named in the families Buccinidae, Columbellidae, Cancellariidae, Volutidae, and Turridae.Fourteen new species are described: Belomitra nesiotica n. sp. (Society Islands to Tonga and Fiji in 580–830 m), B.bouteti n. sp. (Society and Tuamotu Islands in 430–830 m), B. subula n. sp. (Solomon Islands to Vanuatu in 760–1110m), B. caudata n. sp. (Sulu Sea in 2300 m), B. gymnobela n. sp. (South Pacific, eastern Indonesia and Philippines in780–2040 m), B. hypsomitra n. sp. (Fiji in 392–407 m), B. brachymitra n. sp. (Fiji in 395–540 m), B. comitas n. sp.(Madagascar and Philippines in 1075–1110 m), B. minutula (Coral Sea in 490 m), B. granulata n. sp. (New Caledoniain 105–860 m), B. reticulata n. sp. (Tonga and Fiji to New Caledonia in 395–656 m), B. decapitata n. sp. (IndianOcean and New Caledonia in 3680–4400 m), B. admete n. sp. (off Sri Lanka in 2540 m), and B. radula n. sp. (Madagascar in 367–488 m).Key-words: Buccinoidea, molecular phylogeny, morphology, anatomy, radula, deep-water fauna

The flora of ultramafic soils in the Australia–Pacific Region: state of knowledge and research priorities

2015 ◽  
Vol 63 (4) ◽  
pp. 173 ◽  
Author(s):  
Antony van der Ent ◽  
Tanguy Jaffré ◽  
Laurent L'Huillier ◽  
Neil Gibson ◽  
Roger D. Reeves
Keyword(s):  
New Zealand ◽  
Western Australia ◽  
New Caledonia ◽  
Morphological Characteristics ◽  
Research Priorities ◽  
Habitat Destruction ◽  
Herbarium Specimens ◽  
Pacific Region ◽  
Ultramafic Soils ◽  
High Concentration

In the Australia–Pacific Region ultramafic outcrops are both widespread and extensive, covering thousands of km2. Soils derived from ultramafic bedrock impose edaphic challenges and are widely known to host highly distinctive floras with high levels of endemism. In the Australia–Pacific Region, the ultramafics of the island of New Caledonia are famed for harbouring 2150 species of vascular plants of which 83% are endemic. Although the ultramafic outcrops in Western Australia are also extensive and harbour 1355 taxa, only 14 species are known to be endemic or have distributions centred on ultramafics. The ultramafic outcrops in New Zealand and Tasmania are small and relatively species-poor. The ultramafic outcrops in Queensland are much larger and host 553 species of which 18 (or possibly 21) species are endemic. Although New Caledonia has a high concentration of Ni hyperaccumulator species (65), only one species from Western Australia and two species from Queensland have so far been found. No Ni hyperaccumulator species are known from Tasmania and New Zealand. Habitat destruction due to forest clearing, uncontrolled fires and nickel mining in New Caledonia impacts on the plant species restricted to ultramafic soils there. In comparison with the nearby floras of New Guinea and South-east Asia, the flora of the Australia–Pacific Region is relatively well studied through the collection of a large number of herbarium specimens. However, there is a need for studies on the evolution of plant lineages on ultramafic soils especially regarding their distinctive morphological characteristics and in relation to hyperaccumulation.

scholarly journals Ultramafic soils and species sorting in the flora of New Caledonia

2010 ◽  
Vol 98 (5) ◽  
pp. 1108-1116 ◽  
Author(s):  
Yohan Pillon ◽  
Jérôme Munzinger ◽  
Hamid Amir ◽  
Michel Lebrun
Keyword(s):  
New Caledonia ◽  
Ultramafic Soils ◽  
Species Sorting

Microbial communities of ultramafic soils in maquis and rainforest at Mont Do, New Caledonia

2009 ◽  
Vol 34 (5) ◽  
pp. 567-576 ◽  
Author(s):  
MELISSA LENCZEWSKI ◽  
LESLEY RIGG ◽  
NEAL ENRIGHT ◽  
TANGUY JAFFRE ◽  
HEIDI KELLY
Keyword(s):  
Microbial Communities ◽  
New Caledonia ◽  
Ultramafic Soils
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