Pools and fluxes of osmolytes in moist soil and dry soil that has been re-wet

Abstract Three different soils – sand, loam and clay – at each of three moisture levels – saturated, intermediate, and dry – were offered to female Melanoplus sanguinipes as oviposition sites. When given a free choice the females preferred moist sand to all other oviposition sites and avoided soil that was completely dry. When no moist soil was available, coarse dry soil was preferred to fine dry soil, but the oviposition rate was reduced. The females would probe and dig at random into any of the soil offered but would withhold their eggs temporarily if the subsurface soil was not moist. Soil water pH appeared to have very little influence on the females' acceptance of an oviposition site as egg pods were deposited in soils with a range of pH from 3.0 to 11.6. It is suggested that although the absence of moisture in the soil may affect the distribution of egg-pods in the microhabitat and may reduce the rate of egg-pod production slightly, the temperature prevailing during the oviposition period is perhaps a more important factor in determining the number of egg-pods deposited.

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Soil solarisation combined with low rates of soil fumigants controls clubroot of cauliflowers, caused by Plasmodiophora brassicae Woron

Australian Journal of Experimental Agriculture ◽

10.1071/ea9910843 ◽

1991 ◽

Vol 31 (6) ◽

pp. 843 ◽

Cited By ~ 8

Author(s):

IJ Porter ◽

PR Merriman ◽

PJ Keane

Keyword(s):

Population Density ◽

Water Content ◽

Methyl Bromide ◽

Plasmodiophora Brassicae ◽

Moist Soil ◽

Combined Treatments ◽

Disease Rating ◽

Dry Soil ◽

Type Water ◽

Soil Fumigants

The effect of solarisation combined with low rates of soil fumigants on the severity of clubroot and yield of cauliflowers was determined at 2 locations in southern Victoria. The effectiveness of treatments was shown to be dependent on location; on the type, water content and temperature of soil; and on the population density of Plasmodiophora brassicae. Yields were reduced depending upon the disease severity, usually within 60 days after transplanting. Propagules of P. brassicae could survive for more than 28 days in ovens at 45�C when in dry soil but died within 14 days at 40�C in moist soil. At Werribee in 1985 on a red brown earth, solarisation combined with dazomet (100 kg dazomet/ha) gave significantly better control than either treatment alone. This treatment reduced P. brassicae in the 0-10 cm layer, reduced the disease rating from 2.7 to 0.9 (0-3), and increased yield from 2.4 to 47 t/ha compared with controls. In 1986, solarisation combined with 98% methyl bromide-2% chloropicrin (100 and 250 kg/ha) reduced the population density of P. brassicae in the 0-10 and 10-20 cm layers of soil, reduced the disease rating from 3 to 1.8, and increased yield from 0 to 22 t/ha. These treatments were more effective than solarisation and dazomet used alone or in combination. At Keysborough in 1985 on a grey sand, separate treatments of solarisation or dazomet (100 and 250 kg dazometha) were as effective as combined treatments and significantly reduced disease and increased yields compared to controls. Solarisation combined with either fumigant significantly reduced the distribution and total number of weeds at all sites and was generally more effective than separate treatments.

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Effect of soil drought on evapotranspiration of a young spruce forest

Journal of Forest Science ◽

10.17221/11871-jfs ◽

2019 ◽

Vol 48 (No. 4) ◽

pp. 166-172 ◽

Cited By ~ 2

Author(s):

F. Matejka ◽

J. Rožnovský ◽

T. Hurtalová ◽

D. Janouš

Keyword(s):

Water Regime ◽

Model Simulation ◽

Global Radiation ◽

Forest Stand ◽

Soil Drought ◽

Transfer Model ◽

Moist Soil ◽

Dry Period ◽

Soil Desiccation ◽

Dry Soil

Daily courses of the actual transpiration of a forest stand were determined by an experimentally verified mathematical Soil – Vegetation – Atmosphere Transfer model. The results refer to the Norway spruce (Picea abies [L.] Karst.) monoculture situated in the highest locations of the Beskids Mts. Drought-free transpiration was estimated as a model simulation run for nonlimiting soil moisture exceeding the level of decreased availability of water. Drought-induced reduction in transpiration was quantified as a difference between actual transpiration and simulated transpiration for moist soil. The results led to conclusions that dry soil causes a significant reduction in actual evapotranspiration and its components in comparison with moist soil. Simultaneously, the effect of soil desiccation was compensated by extremely high evaporative demands of the atmosphere, so that the daily totals of evapotranspiration and its components remained sufficiently high. The high values of global radiation and saturation deficit in the air favourably influenced the water regime of the analysed forest stand in the dry period.

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CONTROL OF CUTWORMS IN ASPARAGUS FIELDS IN THE INTERIOR OF BRITISH COLUMBIA

Canadian Journal of Plant Science ◽

10.4141/cjps57-013 ◽

1957 ◽

Vol 37 (2) ◽

pp. 108-112

Author(s):

F. L. Banham ◽

R. H. Handford

Keyword(s):

British Columbia ◽

Soil Surface ◽

Moist Soil ◽

Highly Effective ◽

Euxoa Ochrogaster ◽

Dry Soil

Emulsions of dieldrin, aldrin, isodrin, toxaphene and chlordane applied to the soil surface and incorporated to a depth of about 4 inches proved highly effective in controlling the red-back cutworm, Euxoa ochrogaster (Guen.) when tested in asparagus fields in the interior of British Columbia in the summer of 1953 and 1954. In 1953 aldrin emulsion mixed with the soil was much more effective than when it was left on the soil surface, Bran bait containing paris green, although giving fairly satisfactory control, was less effective and slower in action than the emulsions. In 1952, dieldrin, aldrin, and isodrin dusts, applied to the soil surface, were superior to and faster in action than bran baits containing aldrin or endrin; all of the 1952 treatments were apparently slower in action in dry soil than in relatively moist soil. A survey of asparagus fields treated by growers in 1953 but not in 1954 indicated that aldrin emulsion, mixed with the soil at about 4 lb. of toxicant per acre, protects asparagus for at least two years.

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The determination of the size distribution of soil clods and crumbs

The Journal of Agricultural Science ◽

10.1017/s0021859600047985 ◽

1940 ◽

Vol 30 (2) ◽

pp. 210-234 ◽

Cited By ~ 13

Author(s):

E. W. Russell ◽

R. V. Tamhane

Keyword(s):

Size Distribution ◽

Maximum Amount ◽

Moist Soil ◽

Personal Factor ◽

Water Stable Aggregates ◽

Dry Soil ◽

Pre Treatment ◽

The Individual ◽

And Training

1. It is possible to determine the size distribution of clods in the field by simple sieving of the soil without any pre-treatment provided the soil is not too wet. There is a personal factor involved in the sieving, but with care and training this will not affect comparisons of results obtained by that person. If the soil is too wet the individual clods smaller than 3 mm. stick together on the 3 mm. sieve. This sticking together is first apparent on the 3 mm. sieve but may become appreciable on the ¼ in. (6 mm.) sieve. No certain way was found for overcoming this difficulty.2. There appears to be no best method for determining the size distribution of the soil crumbs, i.e. of the water-stable aggregates in the soil. The method and the technique must be chosen so as to give the maximum amount of useful information. If an appreciable proportion of the crumbs are larger than ½ mm., a water-sieving method is practically essential.3. The method of wetting to be used can only be chosen from a consideration of what information is wanted. If possible it would be desirable for general purposes to use a very slow or a vacuum wetting technique and a very rapid wetting technique such as wetting the soil by immersion in water.4. The decision whether air-dry or field-moist soil should be used depends entirely on the information needed. For general purposes the use of air-dry soil is recommended.

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Influence of moist - dry cycles on pH changes in surface soils

Soil Research ◽

10.1071/sr98105 ◽

1999 ◽

Vol 37 (6) ◽

pp. 1057 ◽

Cited By ~ 6

Author(s):

K. I. Paul ◽

M. K. Conyers ◽

A. S. Black

Keyword(s):

Soil Moisture ◽

New South ◽

N Mineralisation ◽

Moist Soil ◽

Water Acidification ◽

Acidic Soils ◽

Surface Soils ◽

Soil Layers ◽

South Wales ◽

Dry Soil

It is well established that in the moderately acidic soils of southern Australia, the 0–2 cm layer commonly has a higher pH than soil layers between 2 and 10 cm depth. The surface 2 cm of soil is also exposed to much greater fluctuations of moisture content than deeper soil layers. There are contradictory or speculative reports in the literature on how soil moisture fluctuation affects pH and processes which influence pH. Therefore, the aim of this study was to determine the effect of moist–dry cycles on pH, and on processes involving H+ transformations, in 3 surface soils (0–2 cm) sampled from southern New South Wales. Following a pre-incubation, the 3 surface soils were incubated for 28 days at 30°C and were: (i) maintained continuously dry, (ii) subjected to short (2 days dry, 5 days moist) or long (7 days dry, 7 days moist) moist–dry cycles, or (iii) maintained continuously moist. During the incubation, the pH of continuously dry soil slightly increased by 0.03–0.10 units, while the pH of continuously moist soil decreased by 0.16–0.39 units. In soils subject to both short and long moist–dry cycles, the pH decreased by 0.06–0.34 units. However, relative to soils maintained moist, exposure to moist–dry cycles suppressed acidification by 0.05–0.26 pH units. In dry soils the pH increased, since some of the NH4+-N produced by net N mineralisation was not subsequently nitrified, and there was a net reduction of Mn. In soils which received water, acidification was predominately attributed to nitrification. Relative to soils maintained moist, acidification was suppressed by 1.6–6.5 mmol H+/kg due to the 11–35% decrease of nitrification on exposure to moist–dry cycles. In acidic surface soils (pH <5.5), acidification rates were further suppressed by 0.1–1.0 mmol H+/kg due to the 1.06–2.06 times greater net Mn reduction in moist–dry soils than in continuously moist soils.

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Laboratory study of transformation and recovery of urea-N in three Queensland soils

Soil Research ◽

10.1071/sr9840433 ◽

1984 ◽

Vol 22 (4) ◽

pp. 433 ◽

Cited By ~ 9

Author(s):

CA Campbell ◽

RJK Myers ◽

VR Catchpoole ◽

I Vallis ◽

KL Weier

Keyword(s):

Cation Exchange Capacity ◽

Exchange Capacity ◽

Soil Samples ◽

Moist Soil ◽

Moisture Contents ◽

Recovery Movement ◽

Ammonium N ◽

Prairie Soil ◽

Red Earth ◽

Dry Soil

Recovery, movement and transformations of urea-15N applied to three cultivated Queensland soils were measured as the soil dried out from two initial moisture contents. The soils were a Prairie Soil, a Grey Clay and a Red Earth, providing a range of pH (6.6-8.1) and cation exchange capacity (7-42 C/g). Urea was applied by banding and mixing into the top 2.5 cm layer of soil. Ammonium sulfateJ5N was applied to a second set of soil samples. The soil was incubated at 35�C for 21 days. Recovery of urea-15N was 93-103% of the amount applied in the Prairie Soil, 72-92% in the Grey Clay, and 55-83% in the Red Earth. The larger recoveries were for banding urea into dry soil and the smaller for mixing it into moist soil. Some 15N moved into the 2.5 to 5.0 cm layer of soil, the amounts averaged 21%, 18% and 12% of the amount of 15N recovered in the Red Earth, Grey Clay and Prairie Soil respectively. Transformations of urea-N into ammonium-N approached completion after 3 days when urea was mixed into moist soil, but only 55% of completion after 21 days when it was banded into dry soil. The sequential losses of 15N and changes in the ammonium-N content in the soil demonstrated a strong affinity for ammonia by the Prairie Soil, a moderate affinity by the Grey Clay and a weak affinity by the Red Earth. Special precautions needed in the field to achieve efficient use of urea fertilizer therefore increase in importance from the Prairie Soil to the Grey Clay to the Red Earth.

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Effect of Moisture on Chlorimuron Degradation in Soil

Weed Science ◽

10.1017/s0043174500056496 ◽

1990 ◽

Vol 38 (3) ◽

pp. 256-261 ◽

Cited By ~ 21

Author(s):

Thomas P. Fuesler ◽

Michael K. Hanafey

Keyword(s):

Degradation Products ◽

Moist Soil ◽

Temperature Dependent ◽

Soil Extracts ◽

Dependent Rate ◽

Chemical Hydrolysis ◽

Degradation Rates ◽

Dry Soil ◽

Increasing Temperature ◽

Hydrolysis Of

The overall degradation of chlorimuron was very similar at −0.1 and −1.5 MPa and slightly less in air-dry soil. Degradation rates increased with increasing temperature. The primary 14C-labeled compounds observed in moist-soil extracts were desmethyl chlorimuron and saccharin, while the primary 14C-labeled compound observed in air-dry soil extracts was saccharin. Saccharin is formed quantitatively from ethyl 2-(aminosulfonyl)benzoate (phenylsulfonamide) during extraction and therefore represents phenylsulfonamide formed in the soil as a result of chemical hydrolysis of the sulfonylurea bridge. These degradation products suggest that chemical hydrolysis of the sulfonylurea bridge is the primary mode of degradation in air-dry soil, while microbial degradation and chemical hydrolysis both occur in moist soil. These laboratory results demonstrate that chlorimuron will degrade in air-dry soil at a temperature-dependent rate by chemical hydrolysis.

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FACTORS AFFECTING SUBSEQUENT GERMINATION OF CEREAL SEEDS SOWN IN SOILS OF SUBGERMINATION MOISTURE CONTENT

Canadian Journal of Botany ◽

10.1139/b60-030 ◽

1960 ◽

Vol 38 (3) ◽

pp. 287-306 ◽

Cited By ~ 6

Author(s):

H. A. H. Wallace

Keyword(s):

Moisture Content ◽

Seed Coat ◽

Soil Conditions ◽

Moist Soil ◽

Factors Affecting ◽

Storage Fungi ◽

Untreated Check ◽

Dry Soil ◽

Germinating Seeds ◽

Standard Weight

Seeds of wheat sown in soils of subgermination moisture content sometimes decay and die. The critical moisture content at which maximum seed decay occurs is at a level approximately equal to one-half the difference between air-dry soil and soil moist enough for seed to germinate. The relationship apparently holds irrespective of soil type, even though the actual moisture percentage of different soil types at the critical level is quite distinct. “Dry” soil as used in these studies refers to air-dry soil with 8% moisture added. The subsequent germination of wheat was reduced after 3 days' incubation in “dry” soil at 30 °C, and 14–20 days at 5 °C. Germinability was reduced in strongly saline soil. Different samples of wheat varied greatly in germinability after incubation in “dry” soil. Sterilizing the “dry” soil did not change its effect on germination of various seed lots.Much of the variation in loss of germinability was correlated with thresher injuries to the seed coat. Wheat, rye, and hull-less varieties of oats and barley, especially with seeds of more than standard weight per bushel, are susceptible to thresher injury. Growth cracks, sprouting, and frost injury all affect germination adversely. Cereal seeds with hulls, or with high moisture content, or below standard weight, or of small size, and wheat without projecting embryos, are less susceptible to thresher injury, and to consequent reduction of germinability.The “field” fungi Alternaria sp. and Helminthosporium spp. grew out of cereal seeds plated on potato-sucrose agar or moistened filter paper and from germinated seeds grown in “moist” soil. After incubation in “dry” soil germinating seeds gave rise to Alternaria, but not to Helminthosporium spp. The non-germinating seeds from “dry” soil were infected by “storage” fungi, e.g. Penicillium, Aspergillus, Rhizopus, and Mucor. The “storage” fungi do not usually infect cereal seeds sown in “moist” soil, but in “dry” soil both sound and injured seed can be infected. The infection of sound seed is slow, permitting the seed to germinate, but injured seed is infected rapidly and does not germinate. The “storage” fungi invade seeds already infected by “field” fungi and inhibit the growth of the latter.All samples of treated and untreated wheat seed sown in “moist” soil gave good germination. After incubation in “dry” soil the germination of treated seed was fair to good, and of untreated seed was poor to good. Treatment with formalin before incubation in “dry” soil doubled the germination; treatment with Ceresan M, Half-ounce Leytosan, and a water soak trebled germination compared with the untreated check. However, the best treatment in “dry” soil gave 31% less germination than the untreated check sown in “moist” soil. Under “dry” soil conditions a sound seed coat appears to provide better protection against seed-decaying organisms than any seed treatment tested.

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Rice (Oryza sativa) Weed Control with Soil Applications of Quinclorac

Weed Technology ◽

10.1017/s0890037x00037404 ◽

1993 ◽

Vol 7 (3) ◽

pp. 600-604 ◽

Cited By ~ 25

Author(s):

Joe E. Street ◽

Thomas C. Mueller

Keyword(s):

Oryza Sativa ◽

Weed Control ◽

Rice Yield ◽

Field Studies ◽

Moist Soil ◽

Weed Species ◽

Application Timing ◽

Soil Application ◽

Pitted Morningglory ◽

Dry Soil

Field studies were conducted from 1988 to 1990 on a Sharkey clay to evaluate residual weed control in rice with quinclorac applied PPI, PRE to dry soil, and PRE to moist soil. Quinclorac applied at 0.4 or 0.6 kg ai ha−1PPI or PRE to dry or moist soil controlled more than 80% of barnyardgrass, pitted morningglory, and hemp sesbania without rice injury. Quinclorac applied at 0.3 kg ha−1controlled these three weed species substantially but inconsistently. No rice injury was observed from any quinclorac treatment. Except for one of three years when irrigation was delayed for 7 d after PRE application to dry soil, application timing did not consistently affect weed control or rice yield.

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