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61.
Zusammenfassung Viele meteorobiologische Untersuchungen lassen vermuten, daß kolloidelektrische Vorgänge im Übertragungsmechanismus zwischen Umwelt und Organismen eine bedeutsame Rolle spielen. Diese Hinweise werden diskutiert und insbesondere die geoelektrischen Faktoren besprochen, die hierin von Einfluß sein können; als Indikatoren erscheinen Erdströme besonders geeignet. An speziellen Erdstromregistrierungen werden eine Anzahl atmosphärischer Einflüsse nachgewiesen. Registrierungen von elektromagnetischen Feldstörungen können aber darüber hinaus auch für die allgemeine Meteorologie und die Wettervorhersage bedeutungsvoll sein.
Summary A great number of meteorobiological investigations induce to suppose that colloido-electric processes are of great importance for the mechanism of transmission between environment and organism. These aspects are discussed and especially the geo-electric factors which therein may have a considerable influence, whereof earth-currents are especially qualified as indicators. Different atmospheric influences are showed by special records of earth-currents; beyond it, the records of electromagnetic field perturbations seem to be important for general meteorology and for weather-forecasting.

Résumé De nombreuses recherches météorobiologiques conduisent à l'hypothèse que des processus colloido-électriques jouent un rôle important dans le mécanisme de translation entre milieu et organisme. Ces aspects sont discutéet et surtout les facteurs géoélectriques qui peuvent y avoir une influence; comme indicateurs les courants telluriques paraissent être au premier plan. Certaines influences atmosphériques sont démontrées par des enregistrements spéciaux de courant tellurique. Par-dessus cela, des enregistrements des perturbations du champs électromagnétique peuvent être de grande importance pour la météorologie générale et pour les prévisions du temps.


Mit 4 Textabbildungen.  相似文献   
62.
A new seafloor observatory, the gas monitoring module (GMM), has been developed for continuous and long-term measurements of methane and hydrogen sulphide concentrations in seawater, integrated with temperature (T), pressure (P) and conductivity data at the seafloor. GMM was deployed in April 2004 within an active gas-bearing pockmark in the Gulf of Patras (Greece), at a water depth of 42 m. Through a submarine cable linked to an onshore station, it was possible to remotely check, via direct phone connection, GMM functioning and to receive data in near-real time. Recordings were carried out in two consecutive campaigns over the periods April–July 2004, and September 2004–January 2005, amounting to a combined dataset of ca. 6.5 months. This represents the first long-term monitoring ever done on gas leakage from pockmarks by means of CH4+H2S+T+P sensors. The results show frequent T and P drops associated with gas peaks, more than 60 events in 6.5 months, likely due to intermittent, pulsation-like seepage. Decreases in temperature in the order of 0.1–1°C (up to 1.7°C) below an ambient T of ca. 17°C (annual average) were associated with short-lived pulses (10–60 min) of increased CH4+H2S concentrations. This seepage “pulsation” can either be an active process driven by pressure build-up in the pockmark sediments, or a passive fluid release due to hydrostatic pressure drops induced by bottom currents cascading into the pockmark depression. Redundancy and comparison of data from different sensors were fundamental to interpret subtle proxy signals of temperature and pressure which would not be understood using only one sensor.  相似文献   
63.
Laboratory experiments were carried out to investigate the performance of an air-bubble barrier and to determine the oil volume passage rate through such a barrier under various oil sample, wind, wave and current conditions. Two empirical equations were derived based on the laboratory data. The first equation determines the relationship between current velocity and the minimum airflow rate required to avoid oil flow through the barrier from the surface. The second equation predicts the dimensionless oil volume passage rate through the barrier under the surface per unit width when the required minimum airflow rate is given in order to prevent oil flow through the barrier from the surface. If the current and wind speed are given, both the minimum required airflow rate for avoiding oil flow through the barrier from the surface, and the dimensionless oil volume passage rate through the barrier under the surface per unit width can be determined.  相似文献   
64.
65.
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   
66.
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   
67.
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   
68.
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  
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   
69.
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 PT 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 PT 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 PT 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   
70.
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   
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