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Cymodocea rotundata is an ecologically important tropical pioneer seagrass species distributed in the Indo‐Pacific region. The population genetic diversity and structure of this species were analysed at 46 sites spanning the Philippines, Ryukyu Islands (northern limit) and Hainan Island, by using microsatellite simple sequence repeat (SSR) markers. Analyses revealed the persistence of C. rotundata likely relies on local population dynamics and fitness influenced by environmental gradients, with sexual reproduction prevalent in the Philippines while the Ryukyu and Hainan populations were predominantly established by clonal spread. Analysis of molecular variance showed significant genetic differentiation (P < 0.001) among three geographic regions: the Philippines, Ryukyu and Hainan. Furthermore, the mean fixation index value was very high (FST = 0.36), indicating poor dispersal potential or limited gene flow. Allelic richness and heterozygosity of C. rotundata was comparable in the Philippines and Ryukyu Islands populations. More private alleles were found in the Philippines and excess heterozygotes in the Ryukyu Islands. STRUCTURE analysis revealed that the Ryukyu and Hainan populations were mosaics of admixed alleles of individuals from the Philippines. An assignment test suggested that recruitment occurs from the Northeast Philippines to Ryukyu Islands. These results suggest that the Philippine populations are tropical seagrass hotspots and perhaps the origin of the populations in the Ryukyu and Hainan Islands. This scenario is most likely driven by the Kuroshio Current and island integration events during plate tectonic activities. The Philippine Archipelago is considered of high importance for conservation objectives and management plan of seagrasses. Likewise, the Ryukyu Islands are also important in terms of conserving regional diversity because locally adapted genotypes have important evolutionary potential in the face of environmental change.  相似文献   
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One way to reduce water consumption in urban areas is by using alternative sources of supply that can be provided by collecting rainwater and reusing wastewater for less restricted purposes. Thus, this study evaluated the characteristics of effluents produced by the wastewater treatment plant (WWTP) of São Paulo International Airport (SPIA), Brazil, in order to reuse it in non‐potable situations. The results achieved, indicated high efficiency in the biological system utilized by SPIA. The removal rates is equal to or >90% for most of the parameters analyzed, among them, fluoride, salinity, nitrite, nitrate, ammonium nitrogen, total nitrogen, phosphorus, sedimentable solids, turbidity, conductivity, apparent color, chemical oxygen demand, biochemical oxygen demand, total organic carbon, fecal coliforms, and oils and greases. Despite the final effluents were good enough to be launched in the local streams, they shall be submitted to a complementary treatment in order to fit some quality parameters to be reused for specific demands (landscape irrigation, toilet flushing, vehicle washing, fire fighting, and dust control).  相似文献   
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On 4 May 1910, the most destructive earthquake in the history of Costa Rica (Ms 6.4) destroyed the city of Cartago, a major city located in the Valle Central of Costa Rica. Using both palaeo‐seismological and morphotectonic analyses, we have found evidence that points to the Aguacaliente Fault (AF) as the source of this earthquake. This structure is a N100° E trending, strike‐slip fault situated to the south of Cartago and within a wide band of deformation. We excavated two trenches near Bermejo, south of Cartago. We found evidence of three surface ruptures within the last 1000 years on this fault. The age of the most recent rupture is consistent with the Cartago 1910 earthquake. The AF is a seismogenic source capable of producing large earthquakes (Mw 6.5–6.9) with an estimated recurrence interval of about 500 years.  相似文献   
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Estimation of design flood in ungauged catchments is a common problem in hydrology. Methods commonly adopted for this task are limited to peak flow estimation, e.g. index flood, rational and regression‐based methods. To estimate complete design hydrograph, rainfall–runoff modelling is preferred. The currently recommended method in Australia known as Design Event Approach (DEA) has some serious limitations since it ignores the probabilistic nature of principal model inputs (such as temporal patterns (TP) and initial loss) except for design rainfall depth. A more holistic approach such as Joint Probability Approach (JPA)/Monte Carlo Simulation Technique (MCST) can overcome some of the limitations associated with the DEA. Although JPA/MCST has been investigated by many researchers, it has been proved to be difficult to apply since its routine application needs readily available regional design data such as stochastic rainfall duration, TP and losses, which are largely unavailable for Australian states. This paper presents regionalization of the model inputs/parameters to the JPA/MCST for eastern New South Wales (NSW) in Australia. This uses data from 86 pluviograph stations and six catchments from NSW to regionalize the input distributions for application with the JPA/MCST. The independent testing to three test catchments shows that the regionalized JPA/MCST generally outperforms the at‐site DEA. The developed regionalized JPA/MCST can be applied at any arbitrary location in eastern NSW. The method and design data developed here although primarily applicable to eastern NSW can be adapted to other Australian states and countries. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Shallow marine sediments and fringing coral reefs of the Buyat-Ratototok district of North Sulawesi, Indonesia, are affected by submarine disposal of tailings from industrial gold mining and by small-scale gold mining using mercury amalgamation. Between-site variation in heavy metal concentrations in shallow marine sediments was partially reflected by trace element concentrations in reef coral skeletons from adjacent reefs. Corals skeletons recorded silicon, manganese, iron, copper, chromium, cobalt, antimony, thallium, and lead in different concentrations according to proximity to sources, but arsenic concentrations in corals were not significantly different among sites. Temporal analysis found that peak concentrations of arsenic and chromium generally coincided with peak concentrations of silica and/or copper, suggesting that most trace elements in the coral skeleton were incorporated into detrital siliciclastic sediments, rather than impurities within skeletal aragonite.  相似文献   
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Mid-Holocene age fossil-fringing reefs occur along the tectonically stable north coast of Java, Indonesia, presenting an opportunity for sea level and paleoclimate reconstruction. The fossil reef at Point Teluk Awur, near Jepara, Central Java, contains two directly superposed horizons of Porites lobata microatolls. Corals in the lower horizon, 80 cm above modern sea level, yielded Uranium series dates of 7090 ± 90 year BP, while corals in the upper horizon at 1.5 m grew at 6960 ± 60 year BP. These dates match the transgressive phase of regional sea-level curves, but suggest a mid-Holocene highstand somewhat older than that recorded on mid-Pacific islands. Paleotemperature was calibrated using Sr/Ca and δ18O values of a modern P. lobata coral and the locally measured sea surface temperature (SST), yielding SST–Sr/Ca and SST–δ18O calibration equations [T Sr/Ca = 91.03–7.35(Sr/Ca) and Td18 \textO T_{{\delta^{18} {\text{O}}}}  = −3.77 to −5.52(δ18O)]. The application of the local equations to Sr/Ca and δ18O measurements on these corals yielded a range of temperatures of 28.8 ± 1.7°C, comparable to that of the modern Java Sea (28.4 ± 0.7°C). A paleo-salinometer [Δδ18O = ∂δ18O/∂T ( Td18 \textO T_{{\delta^{18} {\text{O}}}}  − T Sr/Ca)], re-calculated using the local parameters, also suggests Java Sea mid-Holocene paleosalinity similar to modern values.  相似文献   
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The 329-Mt Brunswick No. 12 volcanogenic massive sulfide deposit (total resource of 163 Mt at 10.4% Zn, 4.2% Pb, 0.34% Cu, and 115 g/t Ag) is hosted within a Middle Ordovician bimodal volcanic and sedimentary sequence. Massive sulfides are for the most part syngenetic, and the bulk of the sulfide ore occurs as a Zn–Pb-rich banded sulfide facies that forms an intimate relationship with a laterally extensive Algoma-type iron formation and defines the Brunswick Horizon. Zone refining of stratiform sulfides is considered to have resulted in the development of a large replacement-style Cu-rich basal sulfide facies, which is generally confined between the banded sulfide facies and an underlying stringer sulfide zone. Complex polyphase deformation and associated lower- to upper-greenschist facies regional metamorphism is responsible for the present geometry of the deposit. Textural modification has resulted in a general increase in grain size through the development of pyrite and arsenopyrite porphyroblasts, which tend to overprint primary mineral assemblages. Despite the heterogeneous ductile deformation, primary features have locally been preserved, such as fine-grained colloform pyrite and base and precious metal zonation within the Main Zone. Base metal and trace element abundances in massive sulfides from the Brunswick No. 12 deposit indicate two distinct geochemical associations. The basal sulfide facies, characterized by a proximal high-temperature hydrothermal signature (Cu–Co–Bi–Se), contains generally low Au contents averaging 0.39 ppm (n = 34). Conversely, Au is enriched in the banded sulfide facies, averaging 1.1 ppm Au (n = 21), and is associated with an exhalative suite of elements (Zn–Pb–As–Sb–Ag–Sn). Finely laminated sulfide lenses hosted by iron formation at the north end of the Main Zone are further enriched in Au, averaging 1.7 ppm (n = 41) and ranging up to 8.2 ppm. Laser ablation inductively coupled plasma-mass spectrometry (ICP-MS) analyses of pyrite (n = 97) from the north end of the Main Zone average 2.6 ppm Au and range from the detection limit (0.015 ppm) to 21 ppm. Overall, these analyses reveal a distinct Au–Sb–As–Ag–Hg–Mn association within pyrite grains. Gold is strongly enriched in large pseudo-primary masses of pyrite that exhibit relict banding and fine-grained cores; smaller euhedral pyrite porphyroblasts, and euhedral rims of metamorphic origin surrounding the pyrite masses, contain much less Au, Sb, Ag, As, and Sn. Arsenopyrite, occurring chiefly as late porphyroblasts, contains less Au, averaging 1.0 ppm and ranging from the detection limit (0.027 ppm) to 6.9 ppm. Depth profiles for single-spot laser ablation ICP-MS analyses of pyrite and arsenopyrite display uniform values of Au and an absence of discrete microscopic inclusions of Au-bearing minerals, which is consistent with chemically bonded Au in the sulfide structure. The pervasive correlation of Au with Sn in the Zn–Pb-rich banded sulfide facies suggests similar hydrothermal behavior during the waxing stages of deposition on the seafloor. Under high temperature (>350oC) and moderate- to low-pH conditions, Au and Sn in hydrothermal fluids would be transported as chlorocomplexes. An abrupt decrease in temperature and aH2S, accompanied by an increase in fO2 and pH during mixing with seawater, would lead to the simultaneous destabilization of both Au and Sn chlorocomplexes. The enrichment of Au in fine-grained laminated sulfides on the periphery of the deposit, accompanied by sporadic occurrences of barite and Fe-poor sphalerite, supports lower hydrothermal fluid temperatures analogous to white smoker activity on the flanks of a large volcanogenic massive sulfide system. In lower temperature (<350oC) and mildly acidic hydrothermal fluids, Au would be transported by thiocomplexes, which exhibit multifunctional (retrograde–prograde) solubility and a capacity to mobilize Au to the outer parts of the sulfide mound. The sluggish nature of this low-temperature venting together with larger variations in ambient fO2 could lead to a sharp enrichment of Au towards the stratigraphic hanging wall of massive sulfide deposits. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
9.
The currently adopted rainfall-based design flood estimation method in Australia, known as design event approach (DEA), has a flaw that is widely criticized by the hydrologists. The DEA is based on the assumption that a rainfall depth of a certain frequency can be transformed to a flood peak of the same frequency by adopting the ‘representative values’ of other model input variables, such as temporal patterns and losses. To overcome the limitation associated with the DEA, this paper develops stochastic model inputs to apply Monte Carlo simulation technique (MCST) for design flood estimation. This uses data from 86 pluviograph stations and six catchments from eastern New South Wales (NSW), Australia, to regionalize the distributions of various input variables (e.g., rainfall duration, inter-event duration, intensity and temporal patterns and loss and routing characteristics) to simulate thousands of flood hydrographs using a nonlinear runoff routing model. The regionalized stochastic inputs are then applied with the MCST to two catchments in eastern NSW. The results indicate that the developed MCST provide more accurate flood quantile estimates than the DEA for the two test catchments. The particular advantage of the new MCST and stochastic design input variables is that it reduces the subjectivity in the selection of model input values in flood modeling. The developed MCST can be adapted to other parts of Australia and other countries.  相似文献   
10.
Tridacnidae shells, a valuable archive of past environments, are common in the Balobok Rockshelter archaeological site on Sanga‐Sanga Island in the south Philippines. This site was occupied during the mid‐Holocene (ca. 5000–8800 14C yr B.P.), a period of Neolithic cultural expansion in the Philippines. This paper focuses on the preservation of two shell specimens, Hippopus hippopus and Tridacna maxima, unearthed from two mid‐Holocene layers within the rockshelter. The shells' mineralogy and microstructure (prismatic and crossed‐lamellar) were studied using micro‐Fourier transform infrared spectroscopy and scanning electron microscopy to determine if the samples were suitable as paleoenvironmental records. Both shells are still aragonitic but aragonite crystals of both microstructure types are partly dissolved. This dissolution, characteristic of meteoric water alteration, precludes their utility in paleoenvironmental geochemical studies. Nevertheless, these shells are abundant in archaeological sites in the region and may be better preserved in other depositional contexts; more studies on Philippine Tridacnidae shell diagenesis are needed. © 2011 Wiley Periodicals, Inc.  相似文献   
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