WIND EFFECT ON DISCER INCORPORATION OF HERBICIDE GRANULES INTO SOIL

1985 ◽  
Vol 65 (2) ◽  
pp. 239-247
Author(s):  
R. L. KUSHWAHA ◽  
W. B. REED
Keyword(s):  
Key Words ◽  
Soil Surface ◽  
Distribution Patterns ◽  
Wind Effect ◽  
Surface Distribution ◽  
Combined Operation ◽  
Wind Velocities

Soil surface distribution patterns of herbicide granules from a Gandy dribble type applicator were determined under different wind velocities in the laboratory and verified in the field. Results indicted that a combined operation of application and incorporation during seeding with a discer would not provide satisfactory placement of granules assuming wind velocities that occur normally in Saskatchewan during the seeding period. Key words: Wind, discer, herbicide granules, incorporation

PALAEO-ECOLOGICAL SIGNIFICANCE OF PALAEOCENE CALCAREOUS ALGAE FROM THE CAUVERY BASIN, INDIA

1970 ◽  
Vol 11 (1) ◽  
Author(s):  
S. Kishore
Keyword(s):  
Key Words ◽  
Tidal Flat ◽  
South India ◽  
Distribution Patterns ◽  
Calcareous Algae ◽  
Ecological Significance ◽  
Cauvery Basin ◽  
Ecological Information

Palaeocene limestone of the Ninniyur Formation of the Cauvery Basin contains abundant well-preserved calcareous algae. These various types of calcareous algal seem to be controlled by the characteristics of each type environments in which they developed and thus they provide useful palaeo-ecological information of the Ninniyur Formation. The distribution patterns of these groups of calcareous algae, extending from tidal flat to reefal environments have been observed in the Palaeocene of the Ninniyur Formation, Cauvery Basin South India. Key words: Ninniyur formation, Calcareous algae, Palaeoecology. Ecoprint Vol.11(1) 2004.

EFFECT OF CANOPY AND INCORPORATION ON METRIBUZIN PERSISTENCE IN SOILS

1989 ◽  
Vol 69 (3) ◽  
pp. 711-714 ◽  
Author(s):  
K. I. N. JENSEN ◽  
E. R. KIMBALL ◽  
J. A. IVANY
Keyword(s):  
Key Words ◽  
Half Life ◽  
Field Tests ◽  
Soil Surface ◽  
Bare Soil ◽  
Field Conditions ◽  
Row Width ◽  
Sampling Zone

The half-life of metribuzin applied to a bare soil surface was calculated to be 3–7 d over four field tests. An artificial cover erected after application or a shallow incorporation increased the half-life of metribuzin approximately 2.5- to 3-fold. Leaching out of the 0- to 5-cm-deep sampling zone could not account for loss of metribuzin. It was concluded that metribuzin persistence may be affected by volatility and/or photodecomposition losses under field conditions, especially shortly after application. Key words: Metribuzin half-life, volatility, photodecomposition, row width

Response of some vegetable crops to soil-applied halides

1992 ◽  
Vol 72 (4) ◽  
pp. 555-567 ◽  
Author(s):  
S. C. Sheppard ◽  
W. G. Evenden
Keyword(s):  
Key Words ◽  
Soil Surface ◽  
Competitive Interaction ◽  
The Other ◽  
Vegetable Crops ◽  
Tissue Concentrations ◽  
Industrial Pollutants ◽  
High Concentrations ◽  
Corn Kernels ◽  
Key Words Fluoride

The halide elements are environmentally important and share some common attributes. The heaviest, I, and the lighest, F, are quite toxic and are important industrial pollutants. They are also effectively retained in soils. The others, Cl and Br, can be accumulated to high concentrations in plants, are used in agriculture and are highly mobile in soils. This study investigated the behaviour of the halides in plots, outdoor lysimeters, and laboratory sorption and excised-root experiments. Sorption on soil was ordered as F > I > Br > Cl. Concentrations in plants were generally ordered as CI ≥ Br > > F ≥ I, the inverse of the sorption ordering, as expected. Older tissues, which were also closest to the soil surface, had higher concentrations, and sequestered tissues, such as corn kernels and cabbage heads, had lower concentrations. There was evidence of competitive interaction among the halides and with soil anions such as phosphate and sulfate. This competition reduced the toxicity of I and modified tissue concentrations of the halides, P and S. Another interesting interaction was an increase in Cl and I sorption on soil solids when there were elevated levels or the other halides. Overall, the study of the halides in combination enhanced our understanding of their individual behaviours. Key words: Fluoride, chloride, bromide, iodide, vegetable

scholarly journals Distribution pattern and habitat preference of barking deer (Muntiacus muntjac Zimmermann) in Nagarjun forest, Kathmandu

1970 ◽  
Vol 4 (6) ◽  
pp. 70-74 ◽  
Author(s):  
Ajaya Nagarkoti ◽  
Tej Bahadur Thapa
Keyword(s):  
Distribution Pattern ◽  
Key Words ◽  
Habitat Preference ◽  
Rainy Season ◽  
Distribution Patterns ◽  
Pine Forest ◽  
Oak Forest ◽  
Schima Wallichii

The distribution pattern and habitat preference of barking deer (Muntiacus muntjac Zimmermann) were analyzed during spring and rainy seasons of 2005 in Nagarjun Forest, Kathmandu. A total of 14 observations (seven males and seven females), 247 pellets and 118 footprints of barking deer were recorded in the spring and 14 observations (nine males and five females), 151 pellets and 140 footprints were recorded during the rainy season. The result showed uneven or clumped distribution patterns for deer in both spring (S2√X = 331.03 > 1; Χ² = 331.02, p = 0.01) and rainy season (S2√X = 233.48 > 1; Χ² = 233.48, p = 0.01). Among four types of habitats (Schima wallichii forest, mixed broadleaved forest, pine forest and dry oak forest), the mixed broadleaved forest was much preferred in spring (RPI = 0.81) and pine forest during the rainy season (RPI = 0.15). Key words: Barking deer, Muntiacus muntjac, distribution, habitat preference, Nagarjun forest, Nepal Himalayan Journal of Sciences Vol.4(6) 2007 p.70-74

EFFECT OF TYPE, RATE AND INCORPORATION OF LIME AND OF NITROGEN FERTILIZER AND GYPSUM ON MOVEMENT OF LIME IN SOIL COLUMNS

1986 ◽  
Vol 66 (4) ◽  
pp. 757-762
Author(s):  
P. B. HOYT ◽  
B. G. DROUGHT ◽  
G. H. NEILSEN ◽  
E. HOGUE
Keyword(s):  
Key Words ◽  
Soil Ph ◽  
Nitrogen Fertilizer ◽  
Soil Surface ◽  
Deionized Water ◽  
N Fertilizer ◽  
Soil Columns ◽  
Downward Movement ◽  
Type Rate

Soil columns were used to study downward movement of calcite and dolomite applied at two rates on the soil surface or incorporated 0–5 cm deep in combinations with gypsum and surface-applied N fertilizer. The columns were irrigated with 800 mm of deionized water applied over 3 wk. Incorporation of the liming materials greatly accelerated their downward movement in soil. Calcite and dolomite were equally effective in raising soil pH at the lower depths. Neither gypsum nor fertilizer nor doubling the liming rate had much effect on lime movement. Key words: Lime movement, calcite, dolomite, gypsum

RELATIONSHIPS BETWEEN LEAF AND SOIL BORON AND BORON TOXICITY OF PEACHES IN BRITISH COLUMBIA

1985 ◽  
Vol 65 (1) ◽  
pp. 213-217 ◽  
Author(s):  
G. H. NEILSEN ◽  
P. B. HOYT ◽  
J. YORSTON ◽  
W. VAN LIEROP
Keyword(s):  
British Columbia ◽  
Key Words ◽  
Soil Profile ◽  
Soil Surface ◽  
Boron Toxicity ◽  
Leaf Boron

Soil and leaf boron were determined in British Columbia peach orchards exhibiting a range of B concentration, including suspected toxicity. B toxicity always occurred when leaf concentration in May exceeded 130 mg/kg, and frequently occurred when leaf B concentration in July was between 50 and 83 mg/kg. Revised leaf standards were suggested to indicate a desirable range of 26–50 mg/kg leaf B in July. Leaf and soil B for peaches were generally correlated. Exceptions occurred when soil B was concentrated near the soil surface or deep in the soil profile. Leaf B in July was from 26 to 50 mg/kg when soil B to a 90-cm depth ranged from 0.2 to 0.4 mg/L of soil. Key words: Boron toxicity, leaf and soil B, peaches

THE EFFECT OF WATER TABLE DEPTH IN ORGANIC SOIL ON SUBSIDENCE AND SWELLING

1984 ◽  
Vol 64 (2) ◽  
pp. 273-282 ◽  
Author(s):  
J. A. MILLETTE ◽  
R. S. BROUGHTON
Keyword(s):  
Key Words ◽  
Water Table ◽  
Soil Surface ◽  
Organic Soil ◽  
Harvest Time ◽  
Growing Period ◽  
Subsidence Rate ◽  
Soil Subsidence ◽  
Before And After ◽  
Made In

The effects of two water table depths (WTD), 0.6 and 0.9 m below the soil surface on subsidence, subsidence rate and swelling of an organic soil were observed in large undisturbed cores under greenhouse conditions. Measurements were made in two tiers, 0–0.3 m (top tier) and 0.3 m to WTD (bottom tier) during the growth of a carrot crop with WTD as above, and continued following a rise in the water table. The WTD of 0.9 m caused the top tier to subside twice as much as the same tier in the 0.6 m WTD. Top tier subsidence seemed irreversible in both WTD because minor swelling was observed following a rise in the water table. Most of the reversible subsidence occurred in the bottom tier. Raising the water table reduced the total profile subsidence by 36 and 24% for the 0.6 and 0.9 m WTD, respectively. After correction for oxidation, subsidence accounted for 3.2 and 5.9% of the 0.6- and 0.9-m profiles, respectively. The bulk density increase in the 0.6-m profile before and after the end of the experiment was not significant but a significant increase of 11% was measured in the 0.9-m profile. Subsidence rates decreased in both tiers during the growing period reaching a minimum in both WTD at harvest time. The subsidence rate in 0.9-m profile at 100 days after seeding was 2.5 times the rate in the 0.6-m profile. Key words: Organic soil, subsidence, swelling, water table

scholarly journals L-selectin–mediated Leukocyte Adhesion In Vivo: Microvillous Distribution Determines Tethering Efficiency, But Not Rolling Velocity

1999 ◽  
Vol 189 (1) ◽  
pp. 37-50 ◽  
Author(s):  
Jens V. Stein ◽  
Guiying Cheng ◽  
Britt M. Stockton ◽  
Brian P. Fors ◽  
Eugene C. Butcher ◽  
...  
Keyword(s):  
Cell Body ◽  
Leukocyte Adhesion ◽  
Distribution Patterns ◽  
Adhesion Receptors ◽  
High Endothelial Venules ◽  
Surface Distribution ◽  
Rolling Velocity ◽  
Preferential Expression ◽  
Copy Numbers

Adhesion receptors that are known to initiate contact (tethering) between blood-borne leukocytes and their endothelial counterreceptors are frequently concentrated on the microvilli of leukocytes. Other adhesion molecules are displayed either randomly or preferentially on the planar cell body. To determine whether ultrastructural distribution plays a role during tethering in vivo, we used pre-B cell transfectants expressing L- or E-selectin ectodomains linked to transmembrane/intracellular domains that mediated different surface distribution patterns. We analyzed the frequency and velocity of transfectant rolling in high endothelial venules of peripheral lymph nodes using an intravital microscopy model. Ectodomains on microvilli conferred a higher efficiency at initiating rolling than random distribution which, in turn, was more efficient than preferential expression on the cell body. The role of microvillous presentation was less accentuated in venules below 20 μm in diameter than in larger venules. In the narrow venules, tethering of cells with cell body expression may have been aided by forced margination through collision with erythrocytes. L-selectin transfected cells rolled 10-fold faster than E-selectin transfectants. Interestingly, rolling velocity histograms of cell lines expressing equivalent copy numbers of the same ectodomain were always similar, irrespective of the topographic distribution. Our data indicate that the distribution of adhesion receptors has a dramatic impact on contact initiation between leukocytes and endothelial cells, but does not play a role once rolling has been established.

Effects of burial, stem portion and cultivar on the decomposition of canola straw

1999 ◽  
Vol 79 (1) ◽  
pp. 97-100 ◽  
Author(s):  
Peter V. Blenis ◽  
Pak S. Chow ◽  
Gary R. Stringam
Keyword(s):  
Brassica Napus ◽  
Key Words ◽  
Treatment Effects ◽  
Soil Surface ◽  
The Other ◽  
Brassica Napus L ◽  
Straw Decomposition ◽  
One Year ◽  
Surface Decomposition ◽  
Canola Straw

Buried canola straw underwent 1.6 to 2 times as much decomposition as straw on the soil surface. Decomposition of Brassica napus L. was slightly less than that of B. rapa L. and cultivar effects were small in one year and insignificant in the other. Because treatment effects varied between stems and roots, plant portion likely should be considered in decomposition studies. Key words: canola, straw decomposition, burial, cultivars

Distribution patterns and interthalline interactions of epiphytic foliose lichens

1992 ◽  
Vol 70 (4) ◽  
pp. 818-823 ◽  
Author(s):  
Elizabeth John
Keyword(s):  
Key Words ◽  
Interspecific Competition ◽  
Distribution Patterns ◽  
Nearest Neighbour ◽  
Tree Trunk ◽  
Ecological Strategies ◽  
Interspecific Differences ◽  
Flavoparmelia Caperata ◽  
Competition For Resources ◽  
Epiphyte Community

The foliose lichens of a corticolous epiphyte community were sampled using a grid of points and nearest neighbour sampling. Most species were found to have nonrandom distributions with respect to height and aspect on the tree trunk. The tendency of species to form exclusive patches and to contact other species showed large interspecific differences. Some formed monocultures and had fewer interspecific contacts than expected, while others did not form large patches and had more interspecific contacts than expected. Investigation of interspecific thallus overlaps revealed a hierarchy in which heavier species such as Flavoparmelia caperata (2.3 mg/mm2) overtop lighter ones such as Melanelia subaurifera (1.1 mg/mm2) more often than the converse is true. It is likely that being overtopped by another lichen puts a thallus at a disadvantage in competition for resources. The success of a species at overtopping another does not change according to location on the tree trunk. There was evidence that F. caperata excluded other species during succession. Key words: epiphytes, foliose lichens, thallus overlaps, interspecific competition, ecological strategies.

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