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The Kwakshua Watersheds Observatory (KWO) is an integrative watersheds observatory on the coastal margin of a rain-dominated bog-forest landscape in British Columbia (BC), Canada. Established in 2013, the goal of the KWO is to understand and model the flux of terrestrial materials from land to sea – the origins, pathways, processes and ecosystem consequences – in the context of long-term environmental change. The KWO consists of seven gauged watersheds and a network of observation sites spanning from land to sea and along drainage gradients within catchments. Time-series datasets include year-round measurements of weather, soil hydrology, streamflow, aquatic biogeochemistry, microbial ecology and nearshore oceanographic conditions. Sensor measurements are recorded every 5 min and water samples are collected approximately monthly. Additional observations are made during high-flow conditions. We used remote sensing to map watershed terrain, drainage networks, soils and terrestrial ecosystems. The watersheds range in size from 3.2 to 12.8 km2, with varying catchment characteristics that influence hydrological and biogeochemical responses. Despite local variation, the overall study area is a global hotspot for yields of dissolved organic carbon, dissolved organic nitrogen and dissolved iron at the coastal margin. This observatory helps fill an important gap in the global network of observatories, in terms of spatial location (central coast of BC), climate (temperate oceanic), hydrology (very high runoff, pluvial regime), geology (igneous intrusive, glacially scoured), vegetation (bog rainforest) and soils (large stores of organic carbon).  相似文献   
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The equation of motion (Navier-Stokes equation) for a uniformly rotating, compressible, magnetic, viscous fluid is analyzed in terms of infinite series of spherical surface harmonics. Differential equations are obtained for the radial functions of the poloidal and toroidal harmonics of the velocity, corresponding to those obtained by Bullard and Gellman for the magnetic field from the electromagnetic induction equation. This new analysis opens the way for the dynamical problem of electromagnetic induction in the earth's core to be considered by the spherical harmonic method.  相似文献   
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Summary. We give a derivation of the displacement potentials and the wave equations which they satisfy. The derivation is similar to one given by Richards but is more general and yields explicit formulas for the source terms. This generality is retained when the moment tensor representation of the source is used. Formulas for the source terms are given in both spherical and cylindrical coordinate systems and are evaluated for the particular case of a point source with second order moment tensor.  相似文献   
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Local ecological knowledge (LEK) has been recognised as an important source of information for resource management in data-poor fisheries. Our case study of the Foveaux Strait dredge oyster fishery in New Zealand shows LEK can also make a significant contribution to the management of data-rich fisheries, but highlights the importance of appropriate data collection design and interpretation and presentation of LEK. We formalise a structure for interpreting LEK, illustrate the importance of design by comparing two LEK studies, and discuss how the inclusion of LEK into the fisheries plan process has provided unexpected benefits for better management of the fishery.  相似文献   
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