Nutrient Cycling in a Stand of Acacia holosericea A. Cunn. Ex G. Don. III. Calcium, Magnesium, Sodium and Potassium.

1983 ◽  
Vol 31 (2) ◽  
pp. 141 ◽  
Author(s):  
. NP.J ◽  
MJ Dalling
Keyword(s):  
Nutrient Cycling ◽  
Nutrient Addition ◽  
The Other ◽  
Total Rainfall ◽  
Other Hand ◽  
Acacia Holosericea ◽  
Calcium Magnesium ◽  
Sodium And Potassium ◽  
Leaching Surface

Nutrient cycling by a 3-year-old Acacia holosericea plantation (1111 trees ha-1) was studied over a 13-month period. The gross accumulation of each nutrient in the various above-ground organs was calculated from the net increase over the study period plus the amounts lost by leaching and litterfall. Gross accumulation was greatest for calcium (22.4 kg ha-1), and potassium (18.8 kg ha-1), sodium (6.8 kg ha-1), followed by magnesium (5.2 kg ha-1). Biochemical recycling was greatest for calcium (10%) magnesium (8%), sodium (3%) and potassium (2%); however, this may be an overestimate as some of the apparent mobilization was undoubtedly due to leaching. Litter return accounted for 14% of the gross accumulation for potassium, 11% of magnesium, 10% of sodium and 9% of calcium. Litterfall accounted for 90% of the return of calcium to the soil and 75% of the return of magnesium. On the other hand, transfer in solution (leaching, surface wash) accounted for 88% of the return of sodium from the canopy to the soil and 59% of the return of potassium. Over the period 1 January 1979 to 28 February 1980 (total rainfall 2261 mm), the addition of nutrients in area precipitation was greatest for sodium (23.6 kg ha-1), followed by potassium (11.2 kg ha-1), calcium (6.8 kg ha-1) and magnesium (1.8 kg ha-1). Throughfall and stemflow increased the concentration of nutrients, such that the total nutrient addition to the soil was greatest for sodium (28.8 kg ha-1) followed by potassium (15.0 kg ha-1), calcium (7.0 kg ha-1) and magnesium (2.0 kg ha-1). These additions to the soil are significant in relation to the gross accumulation of these elements by Acacia holosericea.

INSULIN EFFECTS ON CALCIUM, MAGNESIUM AND PHOSPHATE METABOLISM IN RATS

1974 ◽  
Vol 75 (4) ◽  
pp. 748-755 ◽  
Author(s):  
Erling T. Mellerup
Keyword(s):  
Serum Calcium ◽  
Indirect Effects ◽  
Serum Magnesium ◽  
Serum Phosphate ◽  
The Other ◽  
Phosphate Metabolism ◽  
Insulin Administration ◽  
Other Hand ◽  
Calcium Magnesium ◽  
Calcium And Magnesium

ABSTRACT Serum calcium as well as serum magnesium increased after insulin administration to rats. The increase in serum calcuim was followed by a decrease, which did not occur in thyroid-parathyroidectomized animals. The increase in both serum calcium and magnesium may be secondary to a diminished uptake of calcium and magnesium into bone. On the other hand this may be secondary to a decreased uptake of phosphate into bone. The decreased uptake of phosphate into bone may be secondary to the decrease in serum phosphate, which is a well-known phenomenon after insulin administration. In addition to all these indirect effects, insulin directly increased the uptake of magnesium into muscle and probably also the liver, thus counteracting the increase in serum magnesium.

scholarly journals The relation of the concentration of macronutrients in the substrate and in the foliage to cell wall thickness and cellulose concentration in the xylem of slash pine (Pinus elliotti)

1970 ◽  
Vol 27 (0) ◽  
pp. 295-333
Author(s):  
E. Malavolta ◽  
J.R. Sarruge ◽  
H.P. Haag ◽  
R. Vencovsky ◽  
C.F.O. Santos ◽  
...  
Keyword(s):  
Cell Wall ◽  
Chemical Analysis ◽  
Factorial Design ◽  
Slash Pine ◽  
The Other ◽  
Other Hand ◽  
Calcium Magnesium ◽  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus ◽  
Cellulose Concentration

Sand culture experiments, using a sub-irrigation technique, were installed in order to find out the effects of the macronutrients N, P, K, Ca, Mg and S on growth, aspect, mineral composition, length of fibers, thickness of cell wall and cellulose concentration in slash pine. The aim was to obtain, under controlled conditions, basic information which could eventually lead to practical means designed to increase the rate of growth and to make of slash pine a richer source of cellulose. Nitrogen, Phosphorus, Potassium Experiment A 3 x 3 x 3 factorial design with two replicates was used. Nitrogen was supplied initially at the levels of 25, 50 and 100 ppm; phosphorus was given at the rates of 5, 10 and 20 ppm; potassium was supplied at the rates of 25, 50 and 100 ppm; six months after the experiment was started the first level for each element was dropped to zero. Others macro and all micronutrients were supplied at uniform rates. Fifteen hours of illumination per day were provided. The experimental technique for growing the slash pine seedlings proved quite satisfactory. Symptoms of deficiency of nitrogen, phosphorus and potassium were observed, described and recorded in photographs and water colors. These informations will help to identify abnormalities which may appear under field conditions. Chemical analysis of the several plant parts, on the other hand, give a valuable means to assess the nutritional status of slash pine, thus confirming when needed, the visual diagnosis. The correctness of manurial pratices, on the other hand, can be judged with the help of the analytical data tabulated. Under the experimental conditions nitrogen caused the highest increases on growth, as measured by increments in height and dry weights, whereas the effects of phosphorus and potassium were less marked. Cellulose concentration was not significantly affected by the treatments used. Higher levels of N seemed to decrease both length of fiber elements and the thickness of cell wall. The effects of P and K were not well defined. Calcium, Magnesium, Sulfur Experiment A 3 x 3 x 3 factorial design with two replicates was used. Calcium was supplied initially at the levels of 12.5, 25 and 50 ppm; magnesium and sulfur were given at the rates of 6, 12.5 and 25 ppm. Other macro and micronutrients were supplied at uniform rates, common to all treatments. Three months after starting the experiment the first level for each element was dropped to zero. Symptoms of deficiency of calcium, magnesium and sulfur were observed, described and recorded as in the case of the previous experiment. Chemical analysis were made, both for mineral content and cellulose concentration. Length of fibers and thickness of cell wall were measured. Both calcium and magnesium increase height, sulfur failing to give significant response. Dry weight was beneficially affected by calcium and sulfur. The levels of calcium, magnesium and sulfur in the needles associated with deficiency and maximum growth are comparable with those found in the literature. Cellulose concentration increased when the level of sulfur in the substrate was raised. The thickness of cell wall was negatively affected by the treatments; no effect was observed with regards to length of fibers.

The effect of burning and seasonal rainfall on native pasture at Katherine, N.T

1969 ◽  
Vol 9 (38) ◽  
pp. 295 ◽  
Author(s):  
MJT Norman
Keyword(s):  
Dry Matter ◽  
The Other ◽  
Seasonal Rainfall ◽  
Dry Matter Yield ◽  
Clay Loam ◽  
Total Rainfall ◽  
Other Hand ◽  
Native Pasture ◽  
Dead Material

An 11-year experiment at Katherine, N.T., on the effects of time and frequency of burning on the yield and composition of native pasture on Tippera clay loam is described. In comparison with plots burned biennially in January, April, or September, the annual dry matter and nitrogen production of control plots after 5-10 years of protection from fire was low. On the other hand, production in the first five years after burning of plots that had been protected for five years and then burned was high. Under conditions favouring the accumulation of dead material, a burn every five years or so appears to be more favourable than annual or biennial burning or no burning at all. The contribution of Themeda australis and Chrysopogon fallax to total dry matter yield was negatively related to total rainfall in the two preceding seasons, and that of Sorghum plumosum positively related.

A study of cometary eruptions through OH radio-lines

1999 ◽  
Vol 173 ◽  
pp. 249-254
Author(s):  
A.M. Silva ◽  
R.D. Miró
Keyword(s):  
Short Duration ◽  
Growth Curves ◽  
The Other ◽  
Initial Mass ◽  
Radio Lines ◽  
Other Hand ◽  
Sudden Rise

AbstractWe have developed a model for theH2OandOHevolution in a comet outburst, assuming that together with the gas, a distribution of icy grains is ejected. With an initial mass of icy grains of 108kg released, theH2OandOHproductions are increased up to a factor two, and the growth curves change drastically in the first two days. The model is applied to eruptions detected in theOHradio monitorings and fits well with the slow variations in the flux. On the other hand, several events of short duration appear, consisting of a sudden rise ofOHflux, followed by a sudden decay on the second day. These apparent short bursts are frequently found as precursors of a more durable eruption. We suggest that both of them are part of a unique eruption, and that the sudden decay is due to collisions that de-excite theOHmaser, when it reaches the Cometopause region located at 1.35 × 105kmfrom the nucleus.

Closing the GAP—A 5Å Scanning Microscope

1969 ◽  
Vol 27 ◽  
pp. 6-7
Author(s):  
A. V. Crewe
Keyword(s):  
Normal Form ◽  
The Other ◽  
Resolving Power ◽  
Scanning Microscope ◽  
Conventional Microscope ◽  
Other Hand ◽  
Closing The Gap ◽  
Thermal Sources ◽  
Better Than ◽  
Transmission Microscope

We have become accustomed to differentiating between the scanning microscope and the conventional transmission microscope according to the resolving power which the two instruments offer. The conventional microscope is capable of a point resolution of a few angstroms and line resolutions of periodic objects of about 1Å. On the other hand, the scanning microscope, in its normal form, is not ordinarily capable of a point resolution better than 100Å. Upon examining reasons for the 100Å limitation, it becomes clear that this is based more on tradition than reason, and in particular, it is a condition imposed upon the microscope by adherence to thermal sources of electrons.

Life Beyond 1MeV

1980 ◽  
Vol 38 ◽  
pp. 30-33
Author(s):  
K.H. Westmacott
Keyword(s):  
Electron Microscopy ◽  
Past Experience ◽  
The Other ◽  
Good Case ◽  
Other Hand ◽  
The U.S

Life beyond 1MeV – like life after 40 – is not too different unless one takes advantage of past experience and is receptive to new opportunities. At first glance, the returns on performing electron microscopy at voltages greater than 1MeV diminish rather rapidly as the curves which describe the well-known advantages of HVEM often tend towards saturation. However, in a country with a significant HVEM capability, a good case can be made for investing in instruments with a range of maximum accelerating voltages. In this regard, the 1.5MeV KRATOS HVEM being installed in Berkeley will complement the other 650KeV, 1MeV, and 1.2MeV instruments currently operating in the U.S. One other consideration suggests that 1.5MeV is an optimum voltage machine – Its additional advantages may be purchased for not much more than a 1MeV instrument. On the other hand, the 3MeV HVEM's which seem to be operated at 2MeV maximum, are much more expensive.

Can the Academic Self-Concept be Positive and Realistic?

2005 ◽  
Vol 19 (3) ◽  
pp. 129-132 ◽  
Author(s):  
Reimer Kornmann
Keyword(s):  
Academic Performance ◽  
Opposite Effect ◽  
Self Esteem ◽  
Point Of View ◽  
The Other ◽  
Self Concept ◽  
High Ability ◽  
Self Image ◽  
Other Hand

Summary: My comment is basically restricted to the situation in which less-able students find themselves and refers only to literature in German. From this point of view I am basically able to confirm Marsh's results. It must, however, be said that with less-able pupils the opposite effect can be found: Levels of self-esteem in these pupils are raised, at least temporarily, by separate instruction, academic performance however drops; combined instruction, on the other hand, leads to improved academic performance, while levels of self-esteem drop. Apparently, the positive self-image of less-able pupils who receive separate instruction does not bring about the potential enhancement of academic performance one might expect from high-ability pupils receiving separate instruction. To resolve the dilemma, it is proposed that individual progress in learning be accentuated, and that comparisons with others be dispensed with. This fosters a self-image that can in equal measure be realistic and optimistic.

Stories and the Self

2020 ◽  
Vol 32 (2) ◽  
pp. 47-58 ◽  
Author(s):  
Stefan Krause ◽  
Markus Appel
Keyword(s):  
Meta Analysis ◽  
The Self ◽  
The Other ◽  
Lower Degree ◽  
Contrast Effects ◽  
Self Perception ◽  
Self Perceptions ◽  
Other Hand ◽  
The One ◽  
Implicit And Explicit

Abstract. Two experiments examined the influence of stories on recipients’ self-perceptions. Extending prior theory and research, our focus was on assimilation effects (i.e., changes in self-perception in line with a protagonist’s traits) as well as on contrast effects (i.e., changes in self-perception in contrast to a protagonist’s traits). In Experiment 1 ( N = 113), implicit and explicit conscientiousness were assessed after participants read a story about either a diligent or a negligent student. Moderation analyses showed that highly transported participants and participants with lower counterarguing scores assimilate the depicted traits of a story protagonist, as indicated by explicit, self-reported conscientiousness ratings. Participants, who were more critical toward a story (i.e., higher counterarguing) and with a lower degree of transportation, showed contrast effects. In Experiment 2 ( N = 103), we manipulated transportation and counterarguing, but we could not identify an effect on participants’ self-ascribed level of conscientiousness. A mini meta-analysis across both experiments revealed significant positive overall associations between transportation and counterarguing on the one hand and story-consistent self-reported conscientiousness on the other hand.

Don’t Put Me in This Group

2019 ◽  
Vol 50 (2) ◽  
pp. 80-93
Author(s):  
Jort de Vreeze ◽  
Christina Matschke
Keyword(s):  
Positive Emotions ◽  
Negative Emotions ◽  
Negative Information ◽  
The Self ◽  
The Other ◽  
Other Hand ◽  
Group Memberships

Abstract. Not all group memberships are self-chosen. The current research examines whether assignments to non-preferred groups influence our relationship with the group and our preference for information about the ingroup. It was expected and found that, when people are assigned to non-preferred groups, they perceive the group as different to the self, experience negative emotions about the assignment and in turn disidentify with the group. On the other hand, when people are assigned to preferred groups, they perceive the group as similar to the self, experience positive emotions about the assignment and in turn identify with the group. Finally, disidentification increases a preference for negative information about the ingroup.

ON THE OTHER HAND

1961 ◽  
Vol 6 (6) ◽  
pp. 222-223
Author(s):  
Edwin G. Boring
Keyword(s):  
The Other ◽  
Other Hand
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