The daily fecundity reduction method: a new procedure for estimating adult fish biomass     

Lo  N. Chyan-huei; Hunter  John R.; Moser  H. Geoffrey; Smith  Paul E.; Methot  Richard D. 《ICES Journal of Marine Science》1992,49(2):209-215

  相似文献   

High‐resolution mapping of Manawatu palaeochannels          下载免费PDF全文

Giulia Lo Re  Ian C. Fuller  Giulia Sofia  Paolo Tarolli 《New Zealand geographer》2018,74(2):77-91

New remote sensing techniques, such as airborne laser scanning (LiDAR), have led to a dramatic increase in terrain information, providing new opportunities for landform analysis. A major advance in using LiDAR‐derived high‐resolution topography (HRT) is the capability to provide an accurate and detailed terrain morphology. This study aims to use LiDAR HRT to identify palaeochannels of the Manawatu River (New Zealand) using an automated procedure based on the statistical analysis of landform curvature. The approach can provide rapid assessment and classification of floodplain topography. The proposed analysis is crucial, especially for intensively used floodplains requiring effective flood management and mitigation.  相似文献   

Intense extreme hydro-climatic events take a toll on society     

Bozorg-Haddad  Omid  Zolghadr-Asli  Babak  Chu  Xuefeng  Loáiciga  Hugo A. 《Natural Hazards》2021,108(2):2385-2391

Natural Hazards - In March 2019, the Iranian meteorological organization warned of the formation of several dense precipitation systems throughout the country. This was followed by a chain of storm...  相似文献   

Biodegradative potential and characterization of psychrotolerant polychlorinated biphenyl-degrading marine bacteria isolated from a coastal station in the Terra Nova Bay (Ross Sea, Antarctica)   总被引：4，自引：0，他引：4  

Michaud L  Di Marco G  Bruni V  Lo Giudice A 《Marine pollution bulletin》2007,54(11):1754-1761

Antarctic marine bacteria were screened for their ability to degrade polychlorinated biphenyls (PCB) as the sole carbon and energy source at both 4 degrees C and 15 degrees C. PCB-degrading isolates (7.1%) were identified by sequencing their 16S rDNA as Pseudoalteromonas, Psychrobacter and Arthrobacter members. One representative isolate per genera was selected for evaluating the biodegradative potential under laboratory scale and phenotypically characterized. Removal of individual PCB congeners was between 35.6% and 79.8% at 4 degrees C and between 0.4% and 82.8% at 15 degrees C. Differences in the removal patterns of PCB congeners were observed in relation to the phylogenetic affiliation: Arthrobacter isolate showed similar biodegradation efficiencies when growing at 4 degrees C and 15 degrees C, while Pseudoalteromonas better degraded PCBs at 15 degrees C. No biodegradation was detected for Psychrobacter isolate at 4 degrees C. Results obtained highlight the occurrence of PCB-degrading bacteria in Antarctic seawater and suggest the potential exploitation of autochthonous bacteria for PCB bioremediation in cold marine environments.  相似文献   

大气校正对SPOT卫星遥测水质的影响   总被引：1，自引：0，他引：1  

施明伦  游保杉  万腾州  罗文忆  张伟智 《遥感学报》2006,10(4):548-558

藉由卫星遥测进行河川水质监测，目前尚没有较明确可行之方法，如何利用较为简单且适当的SPOT卫星遥测大气校正方法，正确辨识水体水质，是本研究的主要目的。利用SPOT卫星作两阶段非监督式及监督式自动分类，确认卫星影像中水质测站对应之水体样本，并将所有样本依季节分群，俾让卫星监测水体水质样本较为均质。模拟方式采用多变量回归、类神经网络及判别分析3种模式，并比较4种不同之大气校正程序。结果发现。以水质及其指标整体预测来看，类神经网络预测结果较优于多变量回归及判别分析的结果，大气校正方法以直接采用灰度值并消除最暗像元灰度值之校正方法，即可达到不错之预测结果。综合而言，以SPOT或分辨率更高之卫星光谱遥测水质是简单可行，但仍需更多数据以验证其精确度。  相似文献   

Along-strike variations of P–T conditions in accretionary wedges and syn-orogenic extension,the HP–LT Phyllite–Quartzite Nappe in Crete and the Peloponnese     

Laurent Jolivet  Fabien Trotet  Patrick Monié  Olivier Vidal  Bruno Goffé  Loïc Labrousse  Philippe Agard  Bad'r Ghorbal 《Tectonophysics》2010,480(1-4):133-148

Syn-orogenic detachments in accretionary wedges make the exhumation of high-pressure and low-temperature metamorphic rocks possible with little erosion. The velocity of exhumation within the subduction channel or the accretionary complex, and thus the shape of P–T paths, depend upon the kinematic boundary conditions. A component of slab retreat tends to open the channel and facilitates the exhumation. We document the effect of slab retreat on the shape of P–T paths using the example of the Phyllite–Quartzite Nappe that has been exhumed below the Cretan syn-orogenic detachment during the Miocene in Crete and the Peloponnese. Data show a clear tendency toward colder conditions at peak pressure and during exhumation where the intensity of slab retreat is larger. This spatial evolution of P–T gradient is accompanied with an evolution from a partly coaxial regime below the Peloponnese section of the detachment toward a clearly non-coaxial regime in Crete.  相似文献   

Hydrogeological and thermal characterization of shallow aquifers in the plain sector of Piemonte region (NW Italy): implications for groundwater heat pumps diffusion     

Stefano Lo Russo  Massimo Vincenzo Civita 《Environmental Earth Sciences》2010,60(4):703-713

The low annual and seasonal variability of the shallow groundwater temperature in the alluvial plain aquifers of the Piemonte region (NW Italy) confirmed the potentiality of the low-enthalpy open-loop groundwater heat pumps (GWHP) diffusion to contribute to the reduction of regional greenhouse gas emissions. The distribution of mean groundwater temperatures ranged from a minimum of 10.3°C to a maximum of 17.9°C with a mean of 14.0°C. Differences among diverse areas were slight according with the modest variations in the general climatic condition. Like the air, temperature distribution of the shallow groundwater temperatures is generally similar to topographic elevations in reverse manner. Higher temperature values recorded were typical of summer months (June, July). On the opposite lower values were measured in January and February. No significant difference phase (time) difference between air and groundwater temperature appeared in the data analysis. Besides air-temperature influence (seasonal variability) seemed strictly connected to the depth to groundwater in the measure point and it was negligible when the value was over 9.5 m. For the application of the open-loop systems, extensive examinations of the hydrogeological local conditions should be conducted at site scale and groundwater heat transport modelling should be developed.  相似文献   

Relationship between soil CO<Subscript>2</Subscript> flux and volcanic tremor at Mt. Etna: Implications for magma dynamics     

Andrea Cannata  Gaetano Giudice  Sergio Gurrieri  Placido Montalto  Salvatore Alparone  Giuseppe Di Grazia  Rocco Favara  Stefano Gresta  Marco Liuzzo 《Environmental Earth Sciences》2010,61(3):477-489

Large variations of the CO₂ flux through the soil were observed between November 2002 and January 2006 at Mt. Etna volcano. In many cases, the CO₂ flux was strongly influenced by changes in air temperature and atmospheric pressure. A new filtering method was then developed to remove the atmospheric influences on soil CO₂ flux and, at the same time, to highlight the variations strictly related to volcanic activity. Successively, the CO₂ corrected data were quantitatively compared with the spectral amplitude of the volcanic tremor by cross correlation function, cross-wavelet spectrum and wavelet coherence. These analyses suggested that the soil CO₂ flux variations preceded those of volcanic tremor by about 50 days. Given that volcanic tremor is linked to the shallow (a few kilometer) magma dynamics and soil CO₂ flux related to the deeper (~12 km b.s.l.) magma dynamics, the “delayed similarity” between the CO₂ flux and the volcanic tremor amplitude was used to assess the average speed in the magma uprising into the crust, as about 170–260 m per day. Finally, the large amount of CO₂ released before the onset of the 2004–2005 eruption indicated a deep ingression of new magma, which might have triggered such an eruption.  相似文献   

Assessing optical earth observation systems for mapping and monitoring temporary ponds in arid areas     

Valrie Soti  Annelise Tran  Jean-Stphane Bailly  Christian Puech  Danny Lo Seen  Agnes Bgu 《International Journal of Applied Earth Observation and Geoinformation》2009,11(5):344-351

Remote sensing methods for locating and monitoring temporary ponds over large areas in arid lands were tested on a study site in Northern Senegal. Three main results are presented, validated with field data and intended to highlight different spectral, spatial and temporal characteristics of the methods: (1) Among several water indices tested, two Middle Infrared-based indices (MNDWI—Modified Normalized Difference Water Index and NDWI₁—Normalized Difference Water Index) are found to be most efficient; (2) an objective method is given prescribing the necessary sensor spatial resolution in terms of minimal detected pond area; and (3) the potential of multi-temporal MODIS imagery for tracking the filling phases of small ponds is illustrated. These results should assist in epidemiological studies of vector-borne diseases that develop around these ponds, but also more generally for land and water management and preservation of threatened ecosystems in arid areas.  相似文献   

Two-dimensional Hurst Index of Joint Surfaces   总被引：2，自引：1，他引：2  

Z. Y. Yang  C. C. Di  S. C. Lo 《Rock Mechanics and Rock Engineering》2001,34(4):323-345

  相似文献