Annual Variations in Length of Copepods in the Sargasso Sea off Bermuda

1964 ◽  
Vol 44 (3) ◽  
pp. 589-600 ◽  
Author(s):  
Georgiana B. Deevey
Keyword(s):  
Sargasso Sea ◽  
Annual Cycles ◽  
Temperature Range ◽  
Annual Variations ◽  
Intermediate Temperature Range ◽  
Equal Degree ◽  
Total Phytoplankton ◽  
The Mean ◽  
Successive Generations ◽  
Seasonal Length

SUMMARYMeasurements of cephalothorax length were made on the females of five species of oceanic copepods for the period from January 1958 through August 1959. The seasonal length variations of the three species of Pleuromamma (P. piseki, P. abdominalis and P. xiphias) followed the cycle in total phytoplankton. Significant positive correlations were obtained between the mean lengths of P. abdominalis and P. piseki and the mean quantity of phytoplankton of the month previous to sampling, but there was no correlation between length and temperature.The seasonal length variations of females of Haloptilus longicornis and Lucicutia flavicornis differed in pattern from that of the Pleuromamma species and no correlation was found between their mean lengths and the annual cycles of phytoplankton or temperature. These species may feed selectively on some possibly unmeasured fraction of the plankton or on particulate organic matter.Previous work has shown that in waters with a wide temperature range there is a high negative correlation between length and temperature and no correlation between length and phytoplankton. In other regions with an intermediate temperature range the sizes of successive generations of copepods are correlated to almost equal degree with the temperature and the quantity of phytoplankton available during growth. In the Sargasso Sea, where there is a narrow temperature range but a definite seasonal cycle in total phytoplankton, the length variations of the Pleuromamma species are correlated with the phytoplankton cycle and not with temperature.

Non-isothermal crystallization behavior of spinel crystals in FeO-SiO2-TiO2-V2O3-Cr2O3 slag

2018 ◽  
Vol 116 (1) ◽  
pp. 110
Author(s):  
Lixiong Shao ◽  
Jiang Diao ◽  
Wang Zhou ◽  
Tao Zhang ◽  
Bing Xie
Keyword(s):  
Cooling Rate ◽  
Crystallization Behavior ◽  
Crystal Size ◽  
Growth Mechanisms ◽  
Vanadium Slag ◽  
Growth Behaviour ◽  
Temperature Range ◽  
Chromium Spinel ◽  
Mean Diameter ◽  
The Mean

The growth behaviour of spinel crystals in vanadium slag with high Cr2O3 content was investigated and clarified by statistical analyses based on the Crystal Size Distribution (CSD) theory. The results indicate that low cooling rate and Cr2O3 content benefit the growth of spinel crystals. The chromium spinel crystals firstly precipitated and then acted as the heterogeneous nuclei of vanadium and titanium spinel crystals. The growth mechanisms of the spinel crystals at the cooling rate of 5 K/min consist two regimes: firstly, nucleation control in the temperature range of 1873 to 1773 K, in which the shapes of CSD curves are asymptotic; secondly, surface and supply control within the temperature range of 1773 to 1473 K, in which the shapes of CSD curves are lognormal. The mean diameter of spinel crystals increases from 3.97 to 52.21 µm with the decrease of temperature from 1873 to 1473 K.

Relaxation of Dielectric Loss Peak over Intermediate Temperature Range in Bi 5 TiNbWO 15 Intergrowth

2009 ◽  
Vol 26 (4) ◽  
pp. 047701 ◽  
Author(s):  
Wang Wei ◽  
Wang Xiao-Juan ◽  
Zhu Jun ◽  
Mao Xiang-Yu ◽  
Chen Xiao-Bing
Keyword(s):  
Dielectric Loss ◽  
Intermediate Temperature ◽  
Loss Peak ◽  
Temperature Range ◽  
Intermediate Temperature Range

Tri-lithium borate (Li3BO3); a new highly regenerable high capacity CO2 adsorbent at intermediate temperature

2017 ◽  
Vol 5 (42) ◽  
pp. 22224-22233 ◽  
Author(s):  
Takuya Harada ◽  
T. Alan Hatton
Keyword(s):  
High Capacity ◽  
Intermediate Temperature ◽  
Lithium Borate ◽  
Next Generation ◽  
Temperature Range ◽  
Intermediate Temperature Range ◽  
Borate Oxide ◽  
Co2 Adsorbent

A lithium-borate oxide, Li3BO3, is proposed as a next generation high capacity CO2 adsorbent operative over the intermediate temperature range of 500 to 650 °C.

scholarly journals Effect on nitrate concentration in stream water of agricultural practices in small catchments in Brittany: I. Annual nitrogen budgets

2002 ◽  
Vol 6 (3) ◽  
pp. 497-506 ◽  
Author(s):  
L. Ruiz ◽  
S. Abiven ◽  
P. Durand ◽  
C. Martin ◽  
F. Vertès ◽  
...  
Keyword(s):  
Land Use ◽  
Nitrate Concentration ◽  
Stream Water ◽  
Agricultural Practices ◽  
Climatic Conditions ◽  
Nitrogen Budgets ◽  
Annual Variations ◽  
Nitrate Concentrations ◽  
The Mean ◽  
Small Catchments

Abstract. The hydrological and biogeochemical monitoring of catchments has become a common approach for studying the effect of the evolution of agricultural practices on water resources. In numerous studies, the catchment is used as a "mega-lysimeter" to calculate annual input-output budgets. However, the literature reflects two opposite interpretations of the trends of nitrate concentration in streamwater. For some authors, essentially in applied studies, the mean residence time of leached nitrate in shallow groundwater systems is much less than one year and river loads reflect annual land use while for others, nitrate is essentially transport limited, independent of soil nitrate supply in the short term and annual variations reflect changes in climatic conditions. This study tests the effect of agricultural land-use changes on inter-annual nitrate trends on stream water of six small adjacent catchments from 0.10 to 0.57 km2 in area, on granite bedrock, at Kerbernez, in Western Brittany (France). Nitrate concentrations and loads in streamwater have been monitored for nine years (1992 to 2000) at the outlet of the catchments. An extensive survey of agricultural practices from 1993 to 1999 allowed assessment of the nitrogen available for leaching through nitrogen budgets. For such small catchments, year-to-year variations of nitrate leaching can be very important, even when considering the 'memory effect' of soil, while nitrate concentrations in streamwater appear relatively steady. No correlation was found between the calculated mean nitrate concentration of drainage water and the mean annual concentration in streams, which can even exhibit opposite trends in inter-annual variations. The climatic conditions do not affect the mean concentration in streamwater significantly. These results suggest that groundwater plays an important role in the control of streamwater nitrate concentration. Keywords: nitrate, diffuse pollution, agricultural catchment, nitrogen budget, leaching, Kerbernez catchments

scholarly journals Temperature Dependent Seed Germination of Dalbergia nigra Allem (Leguminosae)

2001 ◽  
Vol 44 (4) ◽  
pp. 401-404 ◽  
Author(s):  
Fernanda G. A. Ferraz-Grande ◽  
Massanori Takaki
Keyword(s):  
Seed Germination ◽  
Endangered Species ◽  
High Temperatures ◽  
Broad Temperature Range ◽  
Optimum Temperature ◽  
Temperature Dependent ◽  
Temperature Range ◽  
Dalbergia Nigra ◽  
The Mean ◽  
Kinetics Of

The germination of endangered species Dalbergia nigra was studied and 30.5° C was found as optimum temperature, although the species presented a broad temperature range where germination occurs and light had no effect. The analysis of kinetics of seed germination confirmed the asynchronized germination below and above the optimum temperature. The light insensitive seed and germination also at high temperatures indicated that D. nigra could occur both in understories and gaps where the mean temperature was high.

scholarly journals Tropospheric temperature variation over India and links with the Indian summer monsoon : 1971-2000

MAUSAM ◽  
2022 ◽  
Vol 53 (3) ◽  
pp. 289-308
Author(s):  
D. R. KOTHAWALE ◽  
K. RUPA KUMAR
Keyword(s):  
Summer Monsoon ◽  
Southern Oscillation ◽  
Monsoon Season ◽  
Temporal Variations ◽  
Mean Annual Temperature ◽  
Tropospheric Temperature ◽  
Temperature Variations ◽  
Annual Cycles ◽  
The Mean ◽  
Spatio Temporal

In the context of the ever increasing interest in the regional aspects of global warming, understanding the spatio-temporal variations of tropospheric temperature over India is of great importance. The present study, based on the data from 19 well distributed radiosonde stations for the period 1971-2000, examines the seasonal and annual mean temperature variations at the surface and five selected upper levels, viz., 850, 700, 500, 200 and 150 hPa. An attempt has also been made to bring out the association between tropospheric temperature variations over India and the summer monsoon variability, including the role of its major teleconnection parameter, the El Niño/Southern Oscillation (ENSO).   Seasonal and annual mean all-India temperature series are analyzed for surface and five tropospheric levels.  The mean annual cycles of temperature at different tropospheric levels indicate that the pre-monsoon season is slightly warmer than the monsoon season at the surface, 850 hPa and 150 hPa levels, while it is relatively cooler at all intermediate levels.  The mean annual temperature shows a warming of 0.18° C and 0.3° C per 10 years at the surface and 850 hPa, respectively.   Tropospheric temperature anomaly composites of excess (deficient) monsoon rainfall years show pronounced positive (negative) anomalies during the month of May, at all the levels.  The pre-monsoon pressure of Darwin has significant positive correlation with the monsoon temperature at the surface and 850 hPa.

scholarly journals Characterization of Canadian High Arctic glacier surface albedo from MODIS C6 data, 2001–2016

2017 ◽  
Author(s):  
Colleen A. Mortimer ◽  
Martin Sharp
Keyword(s):  
Large Scale ◽  
Surface Albedo ◽  
Temporal Trends ◽  
Principal Component ◽  
High Arctic ◽  
Shortwave Radiation ◽  
Glacier Surface ◽  
Annual Variations ◽  
The Mean ◽  
Moderate Resolution Imaging Spectroradiometer

Abstract. Inter-annual variations and longer-term trends in the annual mass balance of glaciers in Canada's Queen Elizabeth Islands (QEI) are largely attributable to changes in summer melt. The largest source of melt energy in the QEI in summer is net shortwave radiation, which is modulated by changes in glacier surface albedo. We used measurements from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors to investigate large scale spatial patterns and temporal trends and variability in the summer surface albedo of QEI glaciers and their relationship to observed changes in glacier surface temperature from 2001 to 2016. Mean summer black-sky shortwave broadband albedo (BSA) decreased at a rate of 0.029 ± 0.025 decade-1 over that period. Larger reductions in BSA occurred in July (−0.050 ± 0.031 decade-1). No change in BSA was observed in either June or August. Most of the decrease in BSA, which was greatest at lower elevations around the margins of the ice masses, occurred between 2007 and 2012 when mean summer BSA was anomalously low. The First Principal Component of the 16-year record of mean summer BSA was well correlated with the mean summer North Atlantic Oscillation Index, except in 2006, 2010, and 2016. During this 16-year period, the mean summer LST increased by 0.046 ± 0.036 °C yr-1 and the BSA record was negatively correlated (−0.64, p 

FERTILITY OF BARLEY AUTOTETRAPLOIDS: I. FERTILITY IN SUCCESSIVE GENERATIONS OF FOUR AUTOTETRAPLOID BARLEY VARIETIES AND THE EFFECT OF SELECTION FOR FERTILITY IN THE O.A.C. 21 AUTOTETRAPLOID

1959 ◽  
Vol 39 (1) ◽  
pp. 98-107 ◽  
Author(s):  
E. Reinbergs ◽  
L. H. Shebeski
Keyword(s):  
Promising Method ◽  
Low Fertility ◽  
Fertility Level ◽  
Seed Setting ◽  
The Mean ◽  
Selection For ◽  
Successive Generations ◽  
Subsequent Selection

The differences in fertility of four colchicine-induced autotetraploid barley varieties (Brant, Montcalm, O.A.C. 21 and York) were determined and compared in four successive generations following the induction of tetraploidy. Despite a wide fertility range within each autotetraploid, the varieties tested varied considerably in their mean per cent fertility. Within each variety the mean per cent fertility remained relatively constant from generation to generation. The Montcalm tetraploid had the lowest mean fertility, fluctuating from generation to generation within a range of 6.0 to 10.1 per cent. The O.A.C. 21 tetraploid had the highest mean fertility, fluctuating within a range of 40.0 to 51.3 per cent.Significant differences in fertility of the four autotetraploid varieties were interpreted as indicating that seed-setting ability may be genetically controlled and, therefore, hybridization and subsequent selection could be a promising method for increasing fertility.Continuous selection for either high or low fertility from the C1 to C4 generation did not change the mean per cent fertility level in the O.A.C. 21 tetraploid.

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