Population structure and secondary production of Heteromastus filiformis (Polychaeta: Capitellidae) in the Loire estuary, France

2002 ◽  
Vol 82 (3) ◽  
pp. 395-402 ◽  
Author(s):  
Patrick Gillet ◽  
Eric Gorman
Keyword(s):  
Secondary Production ◽  
Intertidal Zone ◽  
Life Time ◽  
Sediment Layer ◽  
Fresh Weight ◽  
Annual Variations ◽  
Annual Biomass ◽  
The Mean ◽  
Recruitment Period ◽  
Heteromastus Filiformis

A survey was carried out from April 1998 to June 2000 to study the structure and the secondary production of the population of Heteromastus filiformis in the Loire estuary. Each month, samples were collected in the intertidal zone of Mindin harbour. The length of the thorax (L12) was correlated with the fresh weight (FW) with the relation FW=1·49848 L12–3·62804 (r=0·92). In 1999, the mean density was 2184 ind m−2 with a minimum of 1104 ind m−2 in December and a maximum of 3328 ind m−2 in March. The mean annual biomass was 15·4 g m−2 with a minimum of 2·6 g m−2 in December and a maximum of 28·2 g m−2 in March. Most of the histograms of size–frequency are unimodal and could be considered a single cohort except in May and November/December 1999. The abundance and biomass of the population of H. filiformis decreased during summer and winter which are mortality periods and increase during spring and autumn which are recruitment periods for the population. The life time for a cohort was from six to nine months depending on the recruitment period and on the inter-annual variations. The secondary production was estimated by the method of Crisp (1971). The annual secondary production in 1999 was P=104·3 g m−2 with B¯=15·4 g m−2 and P:B¯=6·8. The quantity of sediment reworked by H. filiformis is about 116 l m−2 y−1 or 65 kg m−2 y−1 which is approximately a deep-sediment layer of 12 cm transported to the surface annually.

Production of Freshwater Invertebrate Populations in Lakes

1989 ◽  
Vol 46 (9) ◽  
pp. 1489-1498 ◽  
Author(s):  
Céline Plante ◽  
John A. Downing
Keyword(s):  
Body Mass ◽  
Secondary Production ◽  
Annual Production ◽  
Phosphorus Concentration ◽  
Thermocline Depth ◽  
Significant Difference ◽  
Annual Biomass ◽  
The Mean ◽  
Secondary Productivity ◽  
Individual Body

This research draws together data on the secondary production of 164 invertebrate populations in 51 lakes to test the hypothesis that the annual production of aquatic invertebrate populations is significantly correlated with the mean annual population biomass, individual body mass, and ambient temperature. Further analyses examine the effects of water chemistry, trophic status, and lake morphometry. Mean annual biomass, individual body mass, and the mean annual water temperature accounted for 79% of the variance in the logarithm of annual secondary production. In contrast to the findings of previous studies, the ratio of mean annual production to mean annual biomass [Formula: see text] varied systematically with population biomass. No significant difference was found between the secondary production of littoral and open water invertebrate populations. Analyses also suggest that zoobenthic and zooplanktonic populations of similar biomass, body mass, and temperature have similar rates of secondary productivity. Analyses demonstrate that the total phosphorus concentration in the water column, and other trophic indicators were positively correlated with secondary production. The pH, lake depth, thermocline depth, drainage area, and the water turnover rate were also found to be correlated with the secondary productivity of natural populations of lentic invertebrates.

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 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 

scholarly journals EFFECTIVENESS OF ANTAGONISTIC FUNGI Gliocladium sp. AND Trichoderma harzianum TO CONTROL Colletotrichum spp. on chili (Capsicum annuum L.)

Agrivet ◽  
2021 ◽  
Vol 26 (1) ◽  
pp. 17
Author(s):  
Siti Dailah ◽  
Mofit Eko Poerwanto ◽  
Supono Budi Sutoto
Keyword(s):  
Direct Method ◽  
Block Design ◽  
Fresh Weight ◽  
Antagonistic Fungi ◽  
Anthracnose Disease ◽  
Randomized Block Design ◽  
Three Samples ◽  
Colletotrichum Spp ◽  
The Mean

The productivity of chili in terms of both quality and quantity is suppressed by the attacks of anthracnose disease caused by Colletotrichum spp. Pesticides is commonly used to control the disease. Researched was conducted to determine the antagonistic fungi and the effective dose in inhibiting the growth of the Colletotrichum spp. Antagonistic tests were performed in vivo using the direct method with three replicates. Inhibition test was arranged in a Complete Randomized Block Design (RCBD) with 7 treatments: Control, Gliocladium sp (150, 250, and 350 mL/plant) and T. harzianum (150, 250, and 350 mL/plant) with four replicates and three samples out of 20 plants per treatment. The results showed that the percentage of inhibition of T. harzianum against Colletotrichum sp. is 55% while Gliocladium sp. is 70.33% in antagonistic test. The mean of disease intensity at 11 up to 32 DAI on control is 5.61 ± 0.71% up to 20.30 ± 1.35 % respectively. It is significantly higher than Gliocladium sp. 350 mL/Plant (1.94 ± 0.45 % up to 11.15 ± 0.87 %), T. harzianum 350 mL/Plant (1.10 ± 0.58 % up to 8.68 ± 0.91 %), and T. harzianum 250 mL/Plant (2.28 ± 0.43 % up to 8.75 ± 0.79 %). No significant different is observed on mean of fresh weight of red chili fruit yield per plant. T. harzianum and Gliocladium sp. fungi are effective in controlling the attack of anthracnose disease in chili. The most efficient dose to control anthracnose disease is the application of T. Harzianum or Gliocladium sp at the dose of 250 mL/plant.Key Words: Chilli, Anthracnose, Gliocladium, Trichoderma, Colletotrichum.

scholarly journals SECONDARY PRODUCTION OF Scolelepis goodbodyi (POLYCHAETA: SPIONIDAE) IN A TROPICAL SANDY BEACH IN THE SOUTHWESTERN ATLANTIC, BRAZIL

2020 ◽  
Vol 24 (04) ◽  
pp. 819-833
Author(s):  
Luciana Sanches Dourado Leão ◽  
◽  
Abílio Soares-Gomes ◽  
José Roberto Botelho de Souza ◽  
Cinthya Simone Gomes Santos ◽  
...  
Keyword(s):  
Growth Rate ◽  
Secondary Production ◽  
Environmental Variability ◽  
Trophic Levels ◽  
Southwestern Atlantic ◽  
Web Studies ◽  
Marine Habitats ◽  
Production Values ◽  
Annual Biomass ◽  
Density And Biomass

The secondary production is the result of the functional response of populations subject to various environmental factors. Marine habitats vary in terms of quantity and quality of food supply, and the use of secondary production values, as well as renewal rates (P/B), may be used as estimates for understanding the incorporation of organic matter and energy per unit, population or community in each area. This estimative was performed for the population of Scolelepis goodbodyi in a tropical beach in the Southwestern Atlantic, located in an upwelling area. A comparison of Spionidae and non-spionid populations from different latitudes was also done. The Mass Specific Growth Rate method (MSGR) and the Production/Biomass ratio (P/B) were used to estimate the somatic annual production and average annual biomass. The mean density and biomass were 16.38 ind. m-2 and 2.78 g AFDW m-2,respectively. The secondary production and P/B were 8.3 g AFDW m-2 y-1 and 2.98 y1, respectively. The growth rate in weight was greater for the small size than the large size classes. The largest individuals (W3C = 1.0 mm) showed the lowest biomass and secondary production values. The observed high rates of secondary production and P/B suggest that this S. goodbodyi population can transfer large amounts of biomass to higher trophic levels of the local food web. Studies of the secondary production of spionidae populations in different latitudes, including the population of S. goodbodyi in the beach of Manguinhos, showed variability in their rates probably due to the differences of several factors such as life history and environmental variability

Metabolic control of Argyropelecus hemigymnus photophores: effects of glucose and pyruvate

1991 ◽  
Vol 69 (9) ◽  
pp. 2410-2413 ◽  
Author(s):  
J. Mallefet ◽  
F. Baguet
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Metabolic Control ◽  
Time Course ◽  
Light Emission ◽  
Mesopelagic Fish ◽  
Fresh Weight ◽  
Hypometabolic State ◽  
The Mean ◽  
Mean Time

Modifications in oxygen consumption and luminescence of isolated luminescent organs of the mesopelagic fish Argyropelecus hemigymnus following glucose and pyruvate administration were studied before and during light emission triggered by adrenaline. Isolated photophores (mean fresh weight 13.5 ± 0.9 mg) at rest, i.e., in the absence of light emission, in saline (20 °C) exhibit a respiration rate of 1.045 ± 0.082 (SE) nmol O2/min (n = 35). A significant decrease (p = 0.05) in oxygen consumption was observed after the addition of 5.5 mM glucose. Instead of the oxygen decrease usually observed as a result of control stimulations using adrenaline, photophores pretreated with glucose increased their oxygen uptake in response to adrenaline, and maximal light emission was reduced by 85% (p = 0.01). The addition of 5.5 mM pyruvate induced a significant transient increase (p = 0.05) in oxygen uptake of isolated photophores, though this treatment did not statistically modify the mean time course of oxygen consumption and light emission in response to adrenaline. The hypothesis of a hypometabolic state of the isolated photophores of A. hemigymnus during light emission is discussed.

Effectiveness of Structured Teaching Programme (STP) on knowledge Regarding Selected Minor Ailments of Newborn among Primipara Mothers Admitted in PNC ward, AIIMS Raipur

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Shafna Abdulla TP ◽  
Shafna Abdulla TP ◽  
Shafna Abdulla TP ◽  
Shafna Abdulla TP ◽  
Shafna Abdulla TP ◽  
...  
Keyword(s):  
Disease Process ◽  
Sampling Technique ◽  
Life Time ◽  
Teaching Programme ◽  
Structured Teaching ◽  
Post Test ◽  
Minor Ailments ◽  
The Mean ◽  
Emotional Events ◽  
Structured Questionnaire

Newborn babies constitute the foundation of life. The birth of a baby is one of the most awe inspiring and emotional events that can occur in one’s life time. In India most the mothers are not aware of management regarding minor disorder of newborn (vomiting, diarrhea, physiological jaundice conjunctivitis, umbilical cord infection, skin rashes etc). Mother plays an important role in the identifying minor developmental deviation and early evidences of the disease process because she is constantly and closely watching her baby. Methodology: pre experimental (one group pretest and posttest) design was adopted for this study. The study was conducted at postnatal ward AIIMS Raipur with sample size of 30 primipara mothers. Non probability convenient sampling technique was adopted to select the sample. The data was collected by means of self-structured questionnaire to assess the knowledge among primipara mothers. Result: The mean score of pre-test was 15.36 and mean score of post-test was 22.4 and the mean improvement was 7.04, which is 45.83% of total primipara mothers. The paired ‘t’ value obtained for knowledge was 10.41 which was found significant at 0.05 level (p<0.05) which is 2.05. Which result shows that significantly an improvement in the knowledge of the primipara mothers after the structured teaching programme (STP) on selected minor ailments of newborn.

Qualitative and quantitative variation in the macrobenthic fauna of the Original Lake and new lake areas of Great Lake and Arthurs Lake, Tasmania

1983 ◽  
Vol 34 (5) ◽  
pp. 787 ◽  
Author(s):  
W Fulton
Keyword(s):  
Great Lake ◽  
Quantitative Data ◽  
Benthic Fauna ◽  
Principal Coordinates Analysis ◽  
Qualitative And Quantitative ◽  
Principal Coordinates ◽  
Annual Biomass ◽  
Species Groups ◽  
The Mean ◽  
Flooded Areas

Faunal variation between sample sites in Great Lake and Arthurs Lake, using both qualitative and quantitative data, was analysed. Cluster analysis and principal coordinates analysis showed that the fauna of the original lake areas of both lakes is distinct from the fauna of the newly flooded areas. Closer relationships exist between the faunas of the old level of the two lakes than between the faunas of the old and new levels within either lake. The distinction is not attributable to depth but may be influenced by substrate differences. The effects of abnormal fluctuations in water level on benthic fauna are discussed. Biomass variation between the sample sites was examined in relation to component species groups. The sites at the old level were dominated by oligochaetes whereas chironomids contributed most to the sites at the new level. Consistent seasonal peaks were evident in the biomass at sites at the new level but not at sites at the old. The mean annual biomass levels (wet wt) for Great Lake (13.9 g m-2) and Arthurs Lake (35.9 g m-2) are compared with recorded values for other Australian and overseas lakes. Biomass levels of Australian lakes in general are also discussed.

Production of the Euphausiid Crustacean Thysanoëssa raschii in the Gulf of St. Lawrence

1977 ◽  
Vol 34 (3) ◽  
pp. 443-446 ◽  
Author(s):  
F. Berkes
Keyword(s):  
Field Data ◽  
Zooplankton Biomass ◽  
Total Zooplankton ◽  
Loss Of Weight ◽  
Annual Biomass ◽  
The Mean ◽  
Total Zooplankton Biomass ◽  
Population Numbers

From field data on growth and population numbers, production of Thysanoëssa raschii, excluding molts, was calculated to be about 1.8 mg dry wt∙m−3∙yr−1 in the Gulf of St. Lawrence. The mean annual biomass of T. raschii was 0.47 mg dry wt∙m−3, comprising about 1% of the total zooplankton biomass in the Gulf, and giving a production to biomass (P:B) ratio of about 4. Production and biomass were probably underestimated due to some sampler avoidance, lack of egg to nauplius–metanauplius interval of population production and loss of weight due to leaching in preserved samples.

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