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1.
【目的】滨海湿地生态系统位于淡水与海水交互地带,含有高浓度Fe2+的地下水渗透到沉积物表层形成的湿地径流和周期性潮汐淹水形成的含氧-缺氧界面有利于铁氧化细菌介导的Fe2+的生物氧化过程发生。然而,目前缺乏对滨海湿地生态系统中铁氧化细菌类群的全面评估。【方法】以上海崇明西沙湿地公园及浙江舟山市朱家尖岛东沙沙滩两地共5处滨海湿地沉积物为研究对象,分析沉积物的氧气穿透深度等环境参数,并基于16S rRNA基因扩增子测序技术,全面解析不同滨海湿地生态系统中细菌与铁氧化细菌的群落组成与分布特征。【结果】与崇明西沙湿地相比,朱家尖岛东沙沙滩有更深的氧气穿透深度,达到10 mm以上。非度量多尺度分析(non-metric multidimensional scaling, NMDS)统计结果表明,细菌群落结构主要受到区域位置不同导致的环境条件差异的影响,而铁氧化细菌的群落结构则受到采样的区域位置和沉积物氧气穿透深度的共同影响。崇明西沙湿地和朱家尖岛东沙沙滩的优势细菌为蓝细菌门(Cyanobacteria)、γ-变形菌纲(Gammaproteobacteria)、拟杆菌门(Bacteroidetes)、α-变形菌纲(Alphaproteobacteria)和放线菌门(Actinobacteria);优势铁氧化细菌为嘉利翁氏菌属(Gallionella)、红细菌属(Rhodobacter)、Lepthothrix和Sideroxydans。【结论】通过对崇明西沙湿地和朱家尖岛东沙沙滩沉积物中栖息的铁氧化菌的调查发现,铁氧化细菌的群落组成与湿地沉积物类型导致的氧气穿透深度差异具有密切联系。 相似文献
2.
K. T. Hughes 《New Zealand journal of zoology.》2013,40(4):251-252
Abstract Plantation forests are very important to the New Zealand economy. They cover 1.3 million hectares (5% of the total land area) of New Zealand; 72% of all planted production forests are in the North Island, 40% in the central North Island. The total log volume cut is 14.8 million m3/yr, and the foreign exchange earnings from plantation forestry is $1.9 billion. 相似文献
3.
Role of secondary metabolites as defense chemicals against ice-ice disease bacteria in biofouler at carrageenophyte farms 总被引:1,自引:0,他引:1
Charles S. Vairappan Sangeetha P. Anangdan Kai Lee Tan Shigeki Matsunaga 《Journal of applied phycology》2010,22(3):305-311
Carrageenophyte farming is an expanding economical activity in North Borneo Island, Malaysia. During routine monitoring of
“ice-ice” disease and epiphyte outbreak at commercial farms, it was apparent that culture lines were heavily (60–80%) infested
with biofoulers, particularly Acanthophora spp. and Laurencia majuscula. However, only L. majuscula showed dominance and flourished even during “ice-ice” disease outbreak. Presence of chemical defense against seaweed pathogens
was investigated in two populations of L. majuscula collected from three major carrageenophyte farms in two districts; (A) Lohok Butun, Selakan Island, and Bum-Bum Island, in
Semporna district, and (B) Telutuh, Carrington Reef, and Balambangan Island, in Kudat district. The first population contained
elatol (1), and iso-obtusol (2), and, second population contained (Z)-10,15-dibromo-9-hydroxy-chamigra-1,3(15),7(14)-triene (3) and (E)-10-15-dibromo-9-hydroxy-chamigra-1,3(15),7(14)-triene (4), as their antibacterial metabolites. All four metabolites showed highly selective inhibition against “ice-ice” disease bacteria
compared to human pathogens at 30 μg disk−1. In addition, seasonal variation of these compounds at two representative farms (Selakan Island [P-1] and Balambangan Island
[P-2]) revealed a 120–170% increase in concentration during “ice-ice” disease outbreak. Microscopy of fresh specimens showed
the presence of corps en cerise, which is the synthesis and storage site of halogenated metabolites at superficial cortical cells, branch tips, and trichoblasts.
This suggests the importance of these metabolites as defense chemicals against “ice-ice” disease bacteria in L. majuscula that grows on seaweed culture lines. 相似文献
4.
Abstract The first records of Sitona discoideus and Trifolium repens on Norfolk Island are reported. The identities of both species were confirmed using morphological criteria and nucleotide sequences. Sequence data from the mitochondrial gene cytochrome oxidase subunit 1 of the Norfolk Island S. discoideus specimens were compared with 33 specimens from Australia, New Zealand and France. These data represent the first published sequences for S. discoideus, and suggest that Australia or New Zealand was the source of Norfolk Island's population. The implications of the introduction of S. discoideus to Norfolk Island are discussed. 相似文献
5.
D. R. Towns 《New Zealand journal of zoology.》2013,40(4):389-407
The ecology of the nocturnal black shore skink, Leiolopisma suteri, was studied on a boulder beach at Cable Bay, Motutapu Island, for 19 months. Distributions over a stable beach (Motutapu Island) and an exposed beach (Cuvier Island) were compared, and the effects of storms on the Cable Bay population were noted. Density, aggression, thermal preference, feeding, and fat reserve fluctuations were also studied. The L. suteri population at Cable Bay has, in favourable areas, one of the highest densities (13/m2) recorded for a lizard species. Spatial distribution of this population varies between the different age classes: adults congregate in the most stable areas, whereas hatchlings are commonest in the least stable areas. Storms cause changes in the beach structure and in the spatial limits of the population. 相似文献
6.
H. Moller 《New Zealand journal of zoology.》2013,40(1):55-69
Abstract Tree wetas (Hemideina crassicruris) were studied in kohekohe (Dysoxylum spectabile) forest on Stephens Island, Cook Strait, between 5 and 17 January 1978. Mark and recapture observations suggested a population density of at least 5300 wetas ha?1 and a biomass of 42 kg ha?1. Activity of wetas increased with temperature and humidity. Tuataras are important predators on Stephens Island and probably deter wetas from moving onto the forest floor. The enlarged head and jaws of male wetas are associated with head-on fights for occupancy of galleries. Single, adult males occupy galleries with a harem of up to 9 females. Stridulation was associated with agonistic encounters and was most frequent shortly before dawn. Seventeen percent of males and 42% of females were damaged. Moulting, copulation, and oviposition were observed, and females carried up to 96 mature eggs. Stephens Island tree wetas reach larger sizes overall, and males have relatively larger heads, than in other populations of the Cook Strait region. The number and size of galleries and the presence or absence of predators may be important determinants of weta population density, sex ratio, harem formation, and activity on the ground. 相似文献
7.
Pedro Andrade Pedro Rodrigues Ricardo Jorge Lopes Jaime Albino Ramos Regina Tristão Da Cunha David Gonçalves 《Bird Study》2013,60(4):498-507
Capsule Blackcap Sylvia atricapilla populations from the Azores archipelago show morphological differences to continental birds which are consistent with the ‘Island Rule’.Aims The morphology of insular vertebrates is usually the result of the evolution in their particular environment and leads to predictable morphological patterns, according to the Island Rule. We test the predictions of the Island Rule, using the Blackcap of the Azores archipelago as our model.Methods We compared morphological variation (body size and wing shape) of populations from the nine islands of the Azores to continental birds, using multivariate indexes. Also, we looked at the relationship between these patterns and possible insular ecological drivers of morphological divergence.Results Our findings are concordant with Island Rule predictions, as in general birds from the Azores are larger than continental populations, especially birds from the most distant islands. Wing shape also differs significantly, as Azorean Blackcaps tend to have rounder wings than continental birds with a migratory-like phenotype.Conclusion Overall, we conclude that the observed morphological patterns in Blackcap in the Azores conform in general to the Island Rule predictions. 相似文献
8.
The foraging strategies of king penguins from Heard and Macquarie islands were compared using satellite telemetry, time-depth
recorders and diet samples. Trip durations were 16.8±3.6 days and 14.8±4.1 days at Macquarie and Heard islands, respectively.
At Macquarie Island, total distances travelled were 1281±203 km compared to 1425±516 km at Heard Island. The total time the
penguins spent at sea was 393±66 h at Macquarie Island and 369±108 h at Heard Island. The penguins from Macquarie Island performed
more deep dives than those from Heard Island. King penguins from Macquarie Island travelled 1.5±0.2 km h−1 day−1 compared to 1.3±0.1 km h−1 day−1. At Macquarie Island, 19% of dives were upto 70–90 m depth compared to 35% at Heard Island. The main dietary prey species
were the fish Krefftychthis anderssoni and the squid Moroteuthis ingens in both groups. The differences in the at-sea distribution and the foraging behaviour of the two groups of penguins were
possibly related to differences in oceanography and bathymetric conditions around the two islands. Dietary differences may
be due to interannual variability in prey availability since the two colonies were studied during incubation but in different
years. 相似文献
9.
Geographic isolation interrupted gene flow between populations leading to population differentiation during the long evolutionary period. In this paper, 33 colonies from Damen Island and 100 colonies from adjacent mainland populations, Juxi and Chixi, were analyzed with both mitochondrial tRNAleu-COII sequences and five microsatellite loci. The results showed that Apis cerana cerana population from Damen Island significantly differentiated from its adjacent mainland populations. In addition, Damen Island population showed a lower level of genetic diversity in terms of the number of mitochondrial haplotypes while both island and mainland populations showed a low level of genetic diversity with mutilocus analysis. The divergent small island population A.c. cerana might probably have suffered inbreeding and genetic drift as well as limited gene flow across the strait. Our data provides useful information for management and preservation for the Damen Island population. 相似文献
10.
Vadim Bakalin Vladimir Fedosov Olga Pisarenko Eugene Borovichev 《Journal of bryology》2013,35(3):249-262
Introduction. The Kuril Islands Chain demarcates the boundary between the circumpolar and East Asian floras in the amphi-Pacific and is a trans-Oceanic migration route from warm-temperate insular East Asia to north-east Asia and Beringia. This paper reviews the flora of the northern part of Iturup Island in regards to its bryogeography and taxonomic diversity, as well as its relative position among other bryophyte floras of north-east and East Asia.Methods. The paper uses morphological methods to identify the species composition and detrended correspondence analysis to identify the position of the northern Iturup Island in the system of local floras of the eastern, extra-tropical, Pacific.Key results. The flora is closely related to the bryophyte floras of the southern Kurils and Hokkaido Island, but has been found to be distinctly distant from the ‘true’ cool-temperate East Asian floras, as well as from the boreal and hemiarctic floras of north-east Asia. Instead, the floras of the south Kurils and northern Hokkaido Island belong to a peculiar intermediate phytogeographic province that cannot be unambiguously placed in either the East Asian or circumboreal floristic regions. The hemiboreal character of the bryophyte flora of northern Iturup Island is in contrast to the general appearance of many of the dominant vegetation communities on the island, which are more characteristic of the hemiarctic.Conclusion. There is no robust evidence to refer the bryophyte flora of northern Iturup either to the circumboreal or East Asian Floristic Region, the flora belongs to a unique intermediate province between the two regions. 相似文献
11.
ABSTRACT Kiore (Pacific rat; Rattus exulans) is both a target for eradication and a taonga or highly valued species in New Zealand, and its abundance and distribution vary considerably throughout the country. We investigated reports of an abundant kiore population on Slipper Island (Whakahau), off the east coast of New Zealand’s North Island, in March 2017. We trapped kiore to examine their distribution across a range of habitats with varying degrees of human activity. Kiore were captured in all habitats, with particularly high abundance at a campground with a fruiting fig tree (50 kiore per 100 trap nights corrected for sprung traps). We found no evidence of other rat species; Slipper Island appears to remain one of few New Zealand islands with kiore but without ship rats (Rattus rattus) and Norway rats (R. norvegicus), the two other rat species present in New Zealand. Slipper Island potentially provides opportunities to research kiore behaviour and population dynamics in a New Zealand commensal environment, and genetics of an isolated island population. 相似文献
12.
基于生态系统服务的海南岛自然保护区体系规划 总被引:4,自引:0,他引:4
随着我国生物多样性保护与生态建设的发展,区域尺度自然保护区体系规划得到广泛的关注.以海南岛为例,探索了利用生态系统服务空间格局进行区域自然保护区规划的方法.研究中,首先从生物多样性分布、水源涵养、水资源保护、土壤保持和海岸带防护等5个方面分析了海南岛生态系统服务的空间格局,综合评价单元生态系统重要性;然后基于生态系统服务综合评价结果,并根据海南省保护自然过程与生物多样性并重的要求,识别出生态重要性高但无保护区或保护面积不足的空间单元,提出海南岛自然保护区体系规划.根据本规划,海南岛将共建成规范完善的自然保护区42个,总面积290.14万hm2.其中,陆地自然保护区面积41.26万hm2,占海南岛陆地总面积的11.79%.新建保护区4个(面积8.80万hm2),调整保护区4个(扩大面积8.01万公顷),优化整合原有保护区中的17个为6个,升级保护区4个.结果表明,基于生态系统服务的自然保护区体系规划有助于发挥自然保护区的综合效益,并具有更强的可操作性.将生态系统服务纳入自然保护区体系规划应是今后的发展方向. 相似文献
13.
Barbara?Biondi Elisa?Giannini Lucia?Negri Pietro?Melchiorri Roberta?Lattanzi Federica?Rosso Luigi?Ciocca Raniero?Rocchi
Summary Syntheses are described of new endomorphin 1 and 2 peptoid–peptide hybrids in which Tyr1 and either one or both Phe3 and Phe4 have been replaced by N-substituted-glycine. The preparation is also described of two glycosylated Hyp2-endomorphin 2 analogues in which either 2,3,4,6-tetra-O-acetyl glucose or glucose are β-O-glycosidically linked to the hydroxyproline residue. The Hyp2-endomorphin sequences have also been elongate by adding a C-terminal β-alanine residue and several linear dimers have been prepared by coupling either the native peptides or the modified analogues. The cyclo endomorphin 2 has also been synthesized. Preliminary pharmacological experiments on isolated organ preparations showed that the agonist activities of both endomorphin 1 and 2 are not significantly affected by the Pro/Hyp substitution. Phe4/Nphe substitution in the endomorphin 1 reduced the potency on guinea pig ileum (GPI) by about 100 times and abolished the agonist activity on mouse vas deferens (MVD) preparation. The decrease of the agonist activity induced by modification of one phenylalanine residue only, either Phe3 or Phe4, is lower on endomorphin 2. Either modification of both Phe3 and Phe4 or glycosylation of the Hyp2-endomorphin 2 cancelled any agonist activity on both preparations. The linear peptide dimers [endomorphin 1]2, [endomorphin 2]2, [Hyp2-endomorphin 1]2, [Hyp2-endomorphin 2]2, [Hyp2-endomorphin 1-Hyp2-endomorphin 2]2 or [Hyp2-endomorphin 2-Hyp2-endomorphin 1]2, are 7–19 times less potent than endomorphin 1 on GPI and significantly less active than endomorphins 1 and 2 on MVD. The other afforded modifications significantly affected or abolished the agonist activity of the resulting endomorphin analogues on both GPI and MVD preparations.The α-amino acid residues are of the L-configuration. Standard abbreviations for amino acid derivatives and peptides are according to the suggestions of the IUPAC-IUB Commission on Biochemical Nomenclature (1984) Eur. J. Biochem., 138, 9–37. Abbreviations listed in the guide published in (2003) J. Peptide Sci., 9, 1–8 are used without explanation. 相似文献
14.
ABSTRACT Capsule: Duration and peak frequency of Wren Troglodytes troglodytes songs differ between Welsh islands (Skokholm, Flat Holm, and Sully Island) and a mainland site, suggesting random or cultural divergence. Aims: The study tests for differences in bioacoustic traits in Wren song between four breeding sites. Methods: Songs from breeding male Wrens were recorded from three Welsh islands and a representative location on the local mainland. Each sonogram was measured for six variables from the whole song and two distinct phrases from the beginning and middle. The variables were measured manually using an open source acoustic tool and compared between sites using generalized linear mixed-effects models. Results: There was significant variation in song variables between island sites and the mainland. Skokholm Wren songs were significantly longer in duration than all other sites by up to 66%. Peak frequency was significantly different across all sites with Sully Island having the highest peak frequency and Skokholm the lowest. Conclusion: The differences in song duration and frequency do not directly suggest a trend associated with selective pressures such as habitat or noise, but instead may be explained by non-selective drivers such as cultural drift or local dialect formation. 相似文献
15.
《新西兰生态学杂志》2011,30(3):321-333
Ship rats (Rattus rattus) were removed from sites on Pearl Island, southern Stewart Island, in 2004 and 2005, to test whether they excluded Pacific rats (R. exulans) or Norway rats (R. norvegicus) or both from podocarp-broadleaf forest. As predators can influence habitat use in rodents, Pearl Island was selected because no mammalian predators of rodents are present. Rats were trapped in two other habitats to clarify rat distribution on the island and to obtain samples for stable isotope investigation of food partitioning within habitats. The experimental removal of ship rats failed, as Pacific rats were found to share forest and shrubland with ship rats. This result contrasted with the restricted distribution of Pacific rats on Stewart Island. Ship rats were ubiquitous, and appear to have been the dominant species in podocarp-broadleaf forest on Pearl Island. The largest species, the Norway rat, was trapped only on the foreshore of Pearl Island, but on Stewart Island it is more widespread. Ship rats and Norway rats were partitioning the coastal habitat by exploiting different food sources. Stable isotopic ratios (δ15N and δ13C) in muscle samples from Norway rats revealed a strong marine signature, suggesting intensive foraging in the intertidal zone. Ship rats trapped in the same habitat exhibited mixed terrestrial and marine sources in their diet. There was little obvious partitioning between ship rats and Pacific rats in forest, except a possible delay in breeding in Pacific rats relative to ship rats. Whether Norway rats select the intertidal zone to forage, or were excluded from forest by ship rats is unknown, but competitive exclusion is likely. Estimated densities of rats were low (2.1–5.1 rats ha-1 in forest, 1.42 rats ha-1 in shrubland) and similar to other New Zealand sites with low soil fertility. Further research will be required to elucidate the roles of food quality, habitat structure and predation in facilitating habitat selection in these species. 相似文献
16.
R. M. McDowall 《New Zealand journal of zoology.》2013,40(2):55-77
Abstract New Zealand's two species of freshwater parastacid crayfishes have allopatric distributions, with one species in the North Island and northwestern South Island and the other in the eastern and southern South Island and Stewart Island. This gives the appearance of a vicariance event driven by uplift of the Southern Alps beginning in the Pliocene, and of former land connections across both Cook Strait and Foveaux Strait. However, separation of the two species may date from before the Southern Alps were formed. A diverse series of historical geological events is invoked to explain details of the distributions of these two species. Absence of Paranephrops from intermontane valleys of eastern flanks of the Southern Alps is notably different from patterns seen in freshwater fish species. 相似文献
17.
Jenny Kitchin Barbara I. P. Barratt Scott Jarvie Stephen C. Adolph 《New Zealand journal of zoology.》2013,40(3):256-265
ABSTRACTScats from tuatara (Sphenodon punctatus) were investigated in autumn at ōrokonui Ecosanctuary on South Island, New Zealand. Eighty-seven tuatara had been translocated there 5–7 months previously, either directly from Stephens Island/Takapourewa or via captivity. Tuatara at ōrokonui fed on diverse invertebrates, including beetles, millipedes, spiders, dipteran flies and cave wētā. Prey occurrence in large scats (presumed to come from adults) was similar in frequency to that in small scats (presumed to be from medium–large juveniles), apart from a higher incidence of spiders in those from adults. Tuatara scats contained scarabaeid and large carabid beetles more frequently, and tenebrionid beetles less frequently, than reported on Stephens Island. Unlike tuatara on Stephens Island, those at ōrokonui do not have access to seabirds or tree wētā, and showed no certain predation on passerines or reptiles. Some differences in diet composition may reflect differences in prey availability resulting from the past presence of rodents at ōrokonui. 相似文献
18.
Estimated Impact of feral house mice on sub-Antarctic invertebrates at Marion Island 总被引:1,自引:0,他引:1
Summary The energy metabolism of feral house mice Mus musculus was established on sub-Antarctic Marion Island, using the doubly-labelled water turnover technique. Mean water influx was 565 ml kg-1 day-1 and mean CO2 production was 5.41 ml g-1 h-1, i.e. 3375 kJ kg-1 day-1. From the energy content of the main items (Lepidoptera larvae, Curculionidae) in the diet of the mice it was estimated that the dry mass of food consumed was 3.5 g mouse-1 day-1. The overall impact of mice on invertebrates, based on mean mouse density and the mean percentage invertebrates in the diet, was estimated at 108 g ha-1 day-1 or 39.4 kg ha-1 y-1 (dry mass). Greatest predation pressure was on larvae of the flightless moth Pringleophaga marioni: 65 g ha-1 day-1 or 23.7 kg ha-1 y-1. Insect biomass is lower on Marion Island than on nearby Prince Edward Island, which is mouse-free. It is suggested that populations of certain insects on Marion Island are depressed by the alien mice. 相似文献
19.
Abstract Cohorts of willow sawfly (Nematus oligospilus) were reared in the laboratory on crack willow (Salix fragilis) at seven constant temperatures between 11.3 and 28.8°C. Larvae developed through 5–7 instars. Body size (length) of adult females was influenced by temperature and was strongly correlated with fecundity (R2 = 0.8973). The developmental threshold (to), determined through linear regression, was calculated to be 8.1°C, and the thermal accumulation above to required to complete one generation was 321 degree‐days. The number of degree‐days available for seasonal development of the sawfly at 10 sites throughout New Zealand was calculated. Allowing for the period of diapause, it was estimated that N. oligospilus might potentially develop through up to seven generations per year in the North Island and three generations per year in the south of the South Island. 相似文献
20.
Genetic Diversity and Temporal Variation in the Cyanophage Community Infecting Marine Synechococcus Species in Rhode Island's Coastal Waters 总被引:1,自引:0,他引:1
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The cyanophage community in Rhode Island's coastal waters is genetically diverse and dynamic. Cyanophage abundance ranged from over 104 phage ml−1 in the summer months to less then 102 phage ml−1 during the winter months. Thirty-six distinct cyanomyovirus g20 genotypes were identified over a 3-year sampling period; however, only one to nine g20 genotypes were detected at any one sampling date. Phylogenetic analyses of g20 sequences revealed that the Rhode Island cyanomyoviral isolates fall into three main clades and are closely related to other known viral isolates of Synechococcus spp. Extinction dilution enrichment followed by host range tests and PCR restriction fragment length polymorphism analysis was used to detect changes in the relative abundance of cyanophage types in June, July, and August 2002. Temporal changes in both the overall composition of the cyanophage community and the relative abundance of specific cyanophage g20 genotypes were observed. In some seawater samples, the g20 gene from over 50% of isolated cyanophages could not be amplified by using the PCR primer pairs specific for cyanomyoviruses, which suggested that cyanophages in other viral families (e.g., Podoviridae or Siphoviridae) may be important components of the Rhode Island cyanophage community. 相似文献