Altitudinal and temporal differences in the food of foxes (Vulpes vulpes) at alpine and subalpine altitudes in the Snowy Mountains

2003 ◽  
Vol 30 (3) ◽  
pp. 245 ◽  
Author(s):  
K. Green
Keyword(s):  
Food Chain ◽  
Primary Productivity ◽  
Vulpes Vulpes ◽  
Prey Availability ◽  
Energy Sources ◽  
Temporal Differences ◽  
Alpine Zone ◽  
Subalpine Zone ◽  
Rattus Fuscipes

The diet of foxes over three years at alpine and subalpine altitudes in the Snowy Mountains followed a cyclical change determined by seasonal climatic events that were very marked and predictable and did not allow for great variation in timing of prey availability. The diet was dominated by mammals in winter, with a change in the snow-free months to insects, mainly comprising bogong moths, with grasshoppers becoming important later in the season. Mammals preyed upon at both altitudes were mainly broad-toothed rats (Mastacomys fuscus), bush rats (Rattus fuscipes) and dusky antechinus (Antechinus swainsonii). In the alpine zone, foxes were less dependent upon the food chain deriving from in situ primary productivity than were foxes in the subalpine zone and were more reliant on other energy sources, particularly immigrant bogong moths.

scholarly journals Simulating Spatiotemporal Dynamics of Sichuan Grassland Net Primary Productivity Using the CASA Model and In Situ Observations

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Chuanjiang Tang ◽  
Xinyu Fu ◽  
Dong Jiang ◽  
Jingying Fu ◽  
Xinyue Zhang ◽  
...  
Keyword(s):  
Primary Productivity ◽  
Net Primary Productivity ◽  
Alpine Meadow ◽  
Growth Period ◽  
Temporal Variations ◽  
Light Use Efficiency ◽  
Important Indicator ◽  
Casa Model ◽  
Use Efficiency

Net primary productivity (NPP) is an important indicator for grassland resource management and sustainable development. In this paper, the NPP of Sichuan grasslands was estimated by the Carnegie-Ames-Stanford Approach (CASA) model. The results were validated with in situ data. The overall precision reached 70%; alpine meadow had the highest precision at greater than 75%, among the three types of grasslands validated. The spatial and temporal variations of Sichuan grasslands were analyzed. The absorbed photosynthetic active radiation (APAR), light use efficiency (ε), and NPP of Sichuan grasslands peaked in August, which was a vigorous growth period during 2011. High values of APAR existed in the southwest regions in altitudes from 2000 m to 4000 m. Light use efficiency (ε) varied in the different types of grasslands. The Sichuan grassland NPP was mainly distributed in the region of 3000–5000 m altitude. The NPP of alpine meadow accounted for 50% of the total NPP of Sichuan grasslands.

scholarly journals Estimation of the Particulate Organic Carbon to Chlorophyll-a Ratio Using MODIS-Aqua in the East/Japan Sea, South Korea

2020 ◽  
Vol 12 (5) ◽  
pp. 840 ◽  
Author(s):  
Dabin Lee ◽  
SeungHyun Son ◽  
HuiTae Joo ◽  
Kwanwoo Kim ◽  
Myung Joon Kim ◽  
...  
Keyword(s):  
Organic Carbon ◽  
Particulate Organic Carbon ◽  
Chlorophyll A ◽  
Primary Productivity ◽  
Seasonal Variability ◽  
Japan Sea ◽  
Global Ocean ◽  
Phytoplankton Communities

In recent years, the change of marine environment due to climate change and declining primary productivity have been big concerns in the East/Japan Sea, Korea. However, the main causes for the recent changes are still not revealed clearly. The particulate organic carbon (POC) to chlorophyll-a (chl-a) ratio (POC:chl-a) could be a useful indicator for ecological and physiological conditions of phytoplankton communities and thus help us to understand the recent reduction of primary productivity in the East/Japan Sea. To derive the POC in the East/Japan Sea from a satellite dataset, the new regional POC algorithm was empirically derived with in-situ measured POC concentrations. A strong positive linear relationship (R2 = 0.6579) was observed between the estimated and in-situ measured POC concentrations. Our new POC algorithm proved a better performance in the East/Japan Sea compared to the previous one for the global ocean. Based on the new algorithm, long-term POC:chl-a ratios were obtained in the entire East/Japan Sea from 2003 to 2018. The POC:chl-a showed a strong seasonal variability in the East/Japan Sea. The spring and fall blooms of phytoplankton mainly driven by the growth of large diatoms seem to be a major factor for the seasonal variability in the POC:chl-a. Our new regional POC algorithm modified for the East/Japan Sea could potentially contribute to long-term monitoring for the climate-associated ecosystem changes in the East/Japan Sea. Although the new regional POC algorithm shows a good correspondence with in-situ observed POC concentrations, the algorithm should be further improved with continuous field surveys.

A Comparison of Liquid Scintillation and Geiger–Müller Estimates of Primary Productivity in an in situ Experiment

1973 ◽  
Vol 30 (5) ◽  
pp. 708-711 ◽  
Author(s):  
F. J. Ward ◽  
Masami Nakanishi
Keyword(s):  
Light Intensity ◽  
Surface Area ◽  
Primary Productivity ◽  
Liquid Scintillation ◽  
Lake Biwa ◽  
In Situ Experiment ◽  
M Estimate ◽  
M Estimates ◽  
Loss Rates

For an in situ experiment conducted in Shiozu Bay, Lake Biwa, Japan, primary productivity estimates from liquid scintillation radioactivity counts of wet algae were generally higher than those from Geiger–Müller radioactivity counts of desiccated algae. Values at 0 m were similar, the G–M estimate at 0.5 m was 10% higher, but from 3 to 13 m the liquid scintillation values ranged from 11 to 33% higher than G–M estimates. The 20-m estimates were low and similar. Differences were caused primarily by 14C losses during desiccation prior to G–M counting. Increasing loss rates between 0.5 and 3.0 m may have been caused by decreasing light intensity. On the basis of surface area, the estimate from liquid scintillation data was 27% greater than that obtained from G–M data.

Records of the Mammal Survey Group of Victoria, 1966-80, on the Distribution of Terrestrial Mammals in Victoria

1982 ◽  
Vol 9 (2) ◽  
pp. 177 ◽  
Author(s):  
JWF Hampton ◽  
AE Howard ◽  
JBJL Poynton
Keyword(s):  
Vulpes Vulpes ◽  
The Other ◽  
Trichosurus Vulpecula ◽  
Terrestrial Mammals ◽  
Pseudocheirus Peregrinus ◽  
Antechinus Stuartii ◽  
Rattus Fuscipes ◽  
Hydromys Chrysogaster ◽  
Eleven Species ◽  
Mammal Survey

Records collected by the Mammal Survey Group of Victoria between 1966 and 1980 have been used to map the distributions of 48 species of mammals in Victoria. Data were collected by trapping, spotlighting and chance encounters. On the basis of these records, 11 species were widespread: these are Tachyglossus aculeatus, Omithorynchus anatinus, Antechinus stuartii, Trichosurus vulpecula, Pseudocheirus peregrinus, Macropus giganteus and M. fuliginosus, Wallabia bicolor, Hydromys chrysogaster, Rattus fuscipes, Mus musculus and Vulpes vulpes. Eleven species were very restricted: these are Antechinus minimus, Perameles gunnii, Cercartetus lepidus, Gymnobelideus leadbeuteri, Macropus robustus, Pseudomys apodemoides, P. shortridgei, P. fumeus, P. novaehollandiae, Mastacomys fuscus and Notomys mitchelli. The other 26 species have distributions between these two extremes.

scholarly journals A meta-analysis of in situ degradability of corn grains and non-starch energy sources found in Brazil

2016 ◽  
Vol 11 (21) ◽  
pp. 1902-1907
Author(s):  
Busanello Marcos ◽  
Pedro Velho Jo atilde o ◽  
Augusto Cortiana Tambara Ant ocirc nio ◽  
Regina Moro Alessio Dileta ◽  
Maria Pereira Haygert Velho Ione ◽  
...  
Keyword(s):  
Meta Analysis ◽  
Energy Sources ◽  
Corn Grains

Influence of a polyclonal antibody preparation on the in situ degradability of three energy sources

2011 ◽  
Vol 40 (5) ◽  
Author(s):  
WG Otero ◽  
CT Marino ◽  
FR Alves ◽  
FA Ferreira ◽  
MB Arrigoni ◽  
...  
Keyword(s):  
Polyclonal Antibody ◽  
Energy Sources ◽  
Antibody Preparation

Simulating Gross Primary Productivity of vegetation under soil water stress using in-situ and reanalysis soil moisture data inputs

2020 ◽  
Author(s):  
Timothy Lam ◽  
Amos P. K. Tai
Keyword(s):  
Soil Moisture ◽  
Water Stress ◽  
Soil Water ◽  
Primary Productivity ◽  
Gross Primary Productivity ◽  
Efficiency Coefficient ◽  
Community Land Model ◽  
Soil Water Stress ◽  
Soil Moisture Data

<p>This study utilises in-situ and reanalysis soil moisture data inputs from various sources to evaluate the effect of soil water stress on Gross Primary Productivity (GPP) of different Plant Functional Types (PFTs) using Terrestrial Ecosystem Model in R (TEMIR), which is under development by Tai Group of Atmosphere-Biosphere Interactions (Tai et al. in prep.). An empirical soil water stress function with reference to Community Land Model (CLM) Version 4.5 is employed to quantify water stress experienced by vegetation which hinders stomatal conductance and thus carboxylation rate. The model results are compared against observations at FLUXNET sites in semi-arid regions across the globe at daily timescale where in-situ GPP data is available and water stress inhibits plant functions to some extent. By dividing the soil into two layers (topsoil and root zone), GPP simulation improves significantly comparing with using single layer bulk soil (Modified Nash-Sutcliffe Model Efficiency Coefficient N increases from -0.686 to -0.586). Such upgrade is particularly substantial for vegetation with shallow roots such as grass PFTs. Despite this improvement, the model is characterised by an overall overestimation of GPP when water stress occurs, and inconsistency of accuracy subject to PFTs and degree of water stress experienced. This study informs responses of various PFTs to soil water stress, capacity of TEMIR in simulating the responses, and possible drawbacks of empirical soil water stress functions, and highlights the importance of topsoil moisture data input for vegetation drought monitoring.</p><p>Keywords: Soil water stress, Terrestrial model representation, Photosynthesis, In-situ data, Reanalysis data, FLUXNET</p>

The English–Wabigoon River System: V. Mercury and Selenium Bioaccumulation as a Function of Aquatic Primary Productivity

1983 ◽  
Vol 40 (12) ◽  
pp. 2251-2259 ◽  
Author(s):  
John W. M. Rudd ◽  
Michael A. Turner
Keyword(s):  
Growth Rate ◽  
Primary Productivity ◽  
Growth Rates ◽  
River System ◽  
Whole Body ◽  
Aquatic Food Chain ◽  
Mercury Bioaccumulation ◽  
Aquatic Food ◽  
Stimulation Of

An experiment was carried out in four 100-m3 in situ enclosures to determine the effect of primary production rate on mercury and selenium concentrations of biota and to test the possibility of ameliorating mercury pollution problems by increasing ecosystem primary productivity. Two enclosures were controls. Primary productivity in a third enclosure was increased fourfold by addition of NaNO3 and NaH2PO4. This stimulation was not sufficient to change pH although the growth rate of fish was enhanced. In this enclosure, mercury concentrations in pearl dace (Semotilus margarita) whole body and muscle samples increased two- and five-fold, respectively, exceeding the dilution of mercury by the enhanced growth rates. In the fourth enclosure, at the highest rate of nutrient addition, primary productivity was increased ninefold, pH was elevated from about 7.9 to 9.2, and the growth rate of fish was stimulated. In this case, the elevation of pH retarded the rate of mercury bioaccumulation in comparison with the enclosure of intermediate productivity. Based on these results, stimulation of primary productivity is not recommended as a mercury ameliorating procedure. Stimulation of primary productivity resulted in a general decrease in the concentration of selenium in the aquatic food chain probably resulting from dilution of selenium by enhanced growth rates of fish and other biota.

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