Further Comments on Darcy Paper     

Ralph C. Heath 《Ground water》1994,32(6):1035-1035

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Estimating carbon sequestration in the piedmont ecoregion of the United States from 1971 to 2010   总被引：1，自引：0，他引：1  

Liu  Jinxun  Sleeter  Benjamin M.  Zhu  Zhiliang  Heath  Linda S.  Tan  Zhengxi  Wilson  Tamara S.  Sherba  Jason  Zhou  Decheng 《Carbon balance and management》2016,11(1):1-13

Human activities have diverse and profound impacts on ecosystem carbon cycles. The Piedmont ecoregion in the eastern United States has undergone significant land use and land cover change in the past few decades. The purpose of this study was to use newly available land use and land cover change data to quantify carbon changes within the ecoregion. Land use and land cover change data (60-m spatial resolution) derived from sequential remotely sensed Landsat imagery were used to generate 960-m resolution land cover change maps for the Piedmont ecoregion. These maps were used in the Integrated Biosphere Simulator (IBIS) to simulate ecosystem carbon stock and flux changes from 1971 to 2010. Results show that land use change, especially urbanization and forest harvest had significant impacts on carbon sources and sinks. From 1971 to 2010, forest ecosystems sequestered 0.25 Mg C ha?1 yr?1, while agricultural ecosystems sequestered 0.03 Mg C ha?1 yr?1. The total ecosystem C stock increased from 2271 Tg C in 1971 to 2402 Tg C in 2010, with an annual average increase of 3.3 Tg C yr?1. Terrestrial lands in the Piedmont ecoregion were estimated to be weak net carbon sink during the study period. The major factors contributing to the carbon sink were forest growth and afforestation; the major factors contributing to terrestrial emissions were human induced land cover change, especially urbanization and forest harvest. An additional amount of carbon continues to be stored in harvested wood products. If this pool were included the carbon sink would be stronger.  相似文献   

Book review     

G. P. Glasby  R. A. Heath 《新西兰海洋与淡水研究杂志》2013,47(3-4):524-525

Introduction to Marine Chemistry, by J. P. Riley and R. Chester. Academic, London, 1971. 465 pp. £6.00.  相似文献   

Spatial demography of Calanus finmarchicus in the Irminger Sea     

M.R. Heath  J. Rasmussen  J. Allen  A.S. Brierley  A. Bunker  R. Davidson  W.S.C. Gurney  S. Hay  A.G. Hirst  A. Ingvarsdottir  P. Lindeque  D. Montagnes  R. Pollard  R.A. Saunders  G. Smerdon  P. Walsham  L. Webster 《Progress in Oceanography》2008,76(1):39-88

Continuous Plankton Recorder data suggest that the Irminger Sea supports a major proportion of the surface-living population of the copepod Calanus finmarchicus in the northern North Atlantic, but there have been few studies of its population dynamics in the region. In this paper, we document the seasonal changes in the demographic structure of C. finmarchicus in the Irminger Sea from a field programme during 2001/2002, and the associations between its developmental stages and various apparent bio-physical zones. Overwintering stages were found widely at depth (>500 m) across the Irminger Sea, and surviving females were widely distributed in the surface waters the following spring. However, recruitment of the subsequent generation was concentrated around the fringes of the Irminger Sea basin, along the edges of the Irminger and East Greenland Currents, and not in the central basin. In late summer animals were found descending back to overwintering depths in the Central Irminger Sea. The key factors dictating this pattern of recruitment appear to be (a) the general circulation regime, (b) predation on eggs in the spring, possibly by the surviving G0 stock, and (c) mortality of first feeding naupliar stages in the central basin where food concentrations appear to be low throughout the year.We compared the demographic patterns in 2001/2002 with observations from the only previous major survey in 1963 and with data from the Continuous Plankton Recorder (CPR) surveys. In both previous data sets, the basic structure of G0 ascent from the central basin and G1 recruitment around the fringes was a robust feature, suggesting that it is a recurrent phenomenon. The Irminger Sea is a complex mixing zone between polar and Atlantic water masses, and it has also been identified as a site of sporadic deep convection. The physical oceanographic characteristics of the region are therefore potentially sensitive to climate fluctuations. Despite this, the abundance of C. finmarchicus in the region, as measured by the CPR surveys, appears not to have responded to climate factors linked to the North Atlantic Oscillation Index, in contrast with the stocks in eastern Atlantic areas. We speculate that this may because biological factors (production and mortality), rather than transport processes are the key factors affecting the population dynamics in the Irminger Sea.  相似文献   

Multidrug resistance in the embryos and larvae of the mussel Mytilus edulis.     

I McFadzen  N Eufemia  C Heath  D Epel  M Moore  D Lowe 《Marine environmental research》2000,50(1-5):319-323

Cells exhibiting the multidrug resistance (MDR) phenotype demonstrate a decreased intracellular drug accumulation due to an active outward transport and decreased intracellular flux. This study demonstrates the inhibition of MDR in mussel (Mytilus edulis) embryos and larvae based on a simple bioassay. The development of embryos was assessed and abnormalities identified at key stages of development, including gastrulation, trochophore and prodissoconch stages. The incidence of developmental abnormalities was significantly increased in the presence of vinblastine, MMS, chloroquine, mitomycin-C, cadmium chloride and colchicine, compared to clean seawater. Consistently, there was a further increase in the number and severity of deformities observed when each toxin was added in the presence of verapamil. Larval growth was also significantly impaired in the presence of verapamil. Increased accumulation of fluorescent MDR dyes, such as rhodamine B, has been measured and shown to be verapamil sensitive. This bioassay encompasses a period of intense cellular activity during which the impairment of a number of critical processes results in abnormal growth and development.  相似文献   

Tidal energy loss in coastal embayments     

R.A. Heath 《Estuarine, Coastal and Shelf Science》1981,12(3):279-290

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TERRAFORMING - A DOWN TO EARTH PERSPECTIVE     

M.J. Heath 《地学学报》1991,3(6):655-658

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The growth of density perturbations in the Lemaître universe     

D. J. Heath 《Astrophysics and Space Science》1981,77(1):59-64

The rate of growth of density perturbations in certain Lemaître universes has been investigated using the differential equation derived by Bonnor. The perturbations that must be postulated at decoupling are not significantly different from those required in the conventional zero-pressure Friedmann-Lemaître models.  相似文献   

The Nimbus-4 Backscatter Ultraviolet (BUV) atmospheric ozone experiment — tow years' operation     

Heath  Donald F.  Mateer  Carlton L.  Krueger  Arlin J. 《Pure and Applied Geophysics》1973,106(1):1238-1253

Summary In April 1970 the Backscatter Ultraviolet (BUV) experiment was placed into orbit aboard the Nimbus-4 satellite. This double monochromator experiment measures ultraviolet terrestrial radiance at twelve discrete wavelengths between 2550 Å and 3400 Å. Approximately 100 scans covering a 230 km square are made between terminator crossings on the daylight side of the earth. A colinear photometer channel with the same field of view is used to derive the Lambert reflectivity of the lower boundary of the scattering atmosphere. The extraterrestrial solar irradiance is measured at the northern terminator. The instrument has currently produced almost three years of nearly continuous data which are being used to infer the high-level ozone distribution and total ozone on a global basis. The high-level ozone data have been verified by independent coincident rocket ozone soundings, and the total ozone values show good agreement with Dobson spectrophotometer determinations as well as those made with the Infrared Interferometer Spectrometer also on Nimbus-4. An increase has been observed in equatorial radiance at 2550 Å relative to 2900 Å, which seems to indicate that the amount of ozone in the upper stratosphere is related to the eleven-year solar cycle.  相似文献   

Generation of the M4 tide in Cook Strait,New Zealand     

Dr. Ronald Allan Heath 《Ocean Dynamics》1982,35(6):261-270

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