Chlorsulfuron residues are not accumulating in soils of southern Queensland

1996 ◽  
Vol 36 (2) ◽  
pp. 223 ◽  
Author(s):  
SR Walker ◽  
GR Robinson
Keyword(s):  
Agricultural Soils ◽  
Climatic Factors ◽  
Vertical Movement ◽  
Winter Cereal ◽  
Stubble Retention ◽  
Applied Dose ◽  
Residue Concentration ◽  
A Site ◽  
Residual Herbicide ◽  
Summer Fallow

Chlorsulfuron persistence was measured in soils (to a depth of 150 cm) at 4 sites in the winter cereal region of southern Queensland. The residual herbicide had been applied 6-14 times in the previous 7-14 years. Residues here measured using a bioassay based on suppression of root growth of maize (Zea mays cv. GH5010). Less than 3% of the total applied chlorsulfuron (96-210 g a.i./ha) was detected 6-12 months after the last application, and residues were <0.7 ng/g soil in the surface 30 cm, and <0.3 ng/g below 30 cm. The limited vertical movement of residues was associated with the herbicide being applied in early winter, several months before leaching rains. Changes in residue concentration with time were also measured at a site in central Queensland, and in a fallow management experiment in southern Queensland. Persistence was greater at the cooler, drier site in southern Queensland than in central Queensland; 4544% compared with 3 4 % of applied dose remained 3 months after application respectively. Stubble retention had no effect on persistence, but tillage during the summer fallow increased persistence slightly. There was no evidence of chlorsulfuron residues accumulating and only limited leaching in these alkaline agricultural soils of southern Queensland. Persistence within a season was influenced by soil and climatic factors.

scholarly journals Recolonization by Slugs: Vertical and Horizontal Dispersal by the Field Slug, Deroceras reticulatum

Insects ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 531
Author(s):  
Gordon Port ◽  
Alan Craig ◽  
Mark Shirley
Keyword(s):  
Significant Contribution ◽  
Vertical Movement ◽  
Deroceras Reticulatum ◽  
Ecological Mechanisms ◽  
A Site ◽  
Grassland Site

Following treatment with molluscicides or other controls, slugs can recolonize a site very quickly, but the proportion of the colonizing slugs moving from adjacent areas (horizontal dispersal) and the proportion from within the soil (vertical dispersal) has not previously been established. At a grassland site, barriers were used to exclude and trap slugs in order to estimate horizontal and vertical movement over a period of 32 months. For the first 15 months vertical movement made a significant contribution to the slugs recolonizing a grassland area. The ecological mechanisms occurring and the implications for the control of slugs are discussed.

scholarly journals A Compact Weighing Lysimeter to Estimate the Water Infiltration Rate in Agricultural Soils

Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 180
Author(s):  
Laura Ávila-Dávila ◽  
Manuel Soler-Méndez ◽  
Carlos Francisco Bautista-Capetillo ◽  
Julián González-Trinidad ◽  
Hugo Enrique Júnez-Ferreira ◽  
...  
Keyword(s):  
Agricultural Soils ◽  
Field Capacity ◽  
Mass Conservation ◽  
Infiltration Rate ◽  
Vertical Movement ◽  
Water Infiltration ◽  
Infiltration Capacity ◽  
Silty Loam ◽  
Rain Events ◽  
Weighing Lysimeter

Infiltration estimation is made by tests such as concentric cylinders, which are prone to errors, such as the lateral movement under the ring. Several possibilities have been developed over the last decades to compensate these errors, which are based on physical, electronic, and mathematical principles. In this research, two approaches are proposed to measure the water infiltration rate in a silty loam soil by means of the mass values of a lysimeter weighing under rainfall conditions and different moisture contents. Based on the fact that with the lysimeter it is possible to determine acting soil flows very precisely, then with the help of mass conservation and assuming a downward vertical movement, 12 rain events were analyzed. In addition, it was possible to monitor the behavior of soil moisture and to establish the content at field capacity from the values of the weighing lysimeter, from which both approach are based. The infiltration rate of these events showed a variable rate at the beginning of the rainfall until reaching a maximum, to descend to a stable or basic rate. This basic infiltration rate was 1.49 ± 0.36 mm/h, and this is because soils with fine textures have reported low infiltration capacity. Four empirical or semi-empirical models of infiltration were calibrated with the values obtained with our approaches, showing a better fit with the Horton’s model.

ASSESSMENT OF THE INFLUENCE OF THE MAIN CLIMATIC FACTORS ON THE YIELD OF WINTER CEREAL CROPS ON THE TERRITORY OF BELARUS FOR FORECASTING PURPOSES

2021 ◽  
pp. 41-48
Author(s):  
Halina A. Kamyshenka
Keyword(s):  
Computational Models ◽  
Climatic Factors ◽  
Climatic Conditions ◽  
Yield Variability ◽  
Cereal Crops ◽  
Winter Rye ◽  
Statistical Assessment ◽  
Winter Cereal ◽  
Temperature And Precipitation

The results of a statistical assessment of the influence of changing weather and climatic conditions of the territory of Belarus on the productivity of the main winter cereal crops are presented in order to build computational models of productivity. The calculations were made with respect to the climatic component as a predictor, taking into account the deviations of air temperature and precipitation from the long-term climatic norm of months that have the most significant effect on the yield of the studied crops. For winter rye and wheat, adequate models of yield variability have been built. The research results are relevant for solving forecasting problems.

Soil carbon sequestration and density distribution in a Vertosol under different farming practices

Soil Research ◽  
2004 ◽  
Vol 42 (8) ◽  
pp. 875 ◽  
Author(s):  
W. J. Wang ◽  
R. C. Dalal ◽  
P. W. Moody
Keyword(s):  
Seasonal Variations ◽  
Agricultural Soils ◽  
Cropping System ◽  
Subtropical Climate ◽  
Soil Organic C ◽  
Farming Practices ◽  
Winter Cereal ◽  
Organic C ◽  
Fallow Period

Abstract Agricultural soils play an important role in the global carbon (C) cycling and can act as a significant C sink if managed properly. The long-term (33 years) effects of no till (NT) v. conventional till (CT), stubble retention (SR) v. stubble burning (SB), and N fertiliser application (NF) v. nil N fertilisation (N0) on soil organic C sequestration, and their seasonal variations during the fallow period, were studied in a winter cereal–summer fallow cropping system under semi-arid subtropical climate in Queensland, Australia. The function of different density fractions of soil organic C in determining total organic C (TOC) dynamics and sequestration was investigated. Significant effect of NT, SR, or NF on soil organic C level was observed only in the top 10 cm soil and when they were practiced together, with the TOC contents being 1.1 to 3.4 t/ha higher under NT + NF + SR than under other treatments. There were significant seasonal fluctuations in TOC contents at different stages of the fallow period, and the lowest levels of TOC and treatment effects were observed in the late fallow period. Density fractionation of soil organic C showed that light fraction C (<1.6 g/cm3) declined rapidly during the fallow period and did not accumulate substantially in soil. TOC dynamics, either as a consequence of seasonal variations or as a long-term response to different farming practices, were predominantly controlled by the changes in the heavy fraction C (>1.6 g/cm3).

The rate of carbon change in agricultural soils in Canada at the landscape level

1997 ◽  
Vol 77 (2) ◽  
pp. 219-229 ◽  
Author(s):  
W. N. Smith ◽  
P. Rochette ◽  
C. Monreal ◽  
R. L. Desjardins ◽  
E. Pattey ◽  
...  
Keyword(s):  
Agricultural Soils ◽  
Conventional Tillage ◽  
Crop Rotations ◽  
No Tillage ◽  
Century Model ◽  
No Till ◽  
Carbon Change ◽  
Agricultural Regions ◽  
Summer Fallow ◽  
Lower Loss

The Century model [a computer simulation of the dynamics of soil organic carbon (SOC)] was used to estimate the rate of SOC change in agricultural soil in Canada. The analysis was carried out on 180 Soil Landscapes of Canada (SLC) polygons, representing 15% of the SLC polygons within agricultural regions. The analysis was stratified into soil zones and into soil textural classes. For each sampled polygon, Century was run for 1 to 5 types of crop rotations under conventional-tillage as well as no-tillage, providing that no-till was used on at least 5% of the land. From the Century simulations, it was estimated that the overall rate of SOC loss from agricultural soils in Canada for 1990 was 39.1 kg ha−1 yr−1 This implies that 1.93 Mt of SOC (7.08 Mt of CO2) was lost from agricultural soils in Canada. Compared to 1990, the SOC loss was estimated to have been greater by 11.9 kg ha−1 yr−1 in 1980 and 9.1 kg ha−1 yr−1 in 1985. The lower loss in 1990 was primarily due to the incorporation of no-till practices and reduction of summer fallow in the mid 1980s. In 1990, at the provincial level, Alberta had the highest rate of SOC loss at 74.5 kg ha−1 yr−1 followed by Manitoba with 66.1 kg ha−1 yr−1 In Ontario, Quebec, and the Atlantic Provinces the average provincial rate of SOC loss was less than 35 kg ha−1 yr−1 Higher SOC loss rates were typically found in soils with coarser texture and greater native SOC content. Key words: Carbon dioxide, greenhouse gas, Century model

scholarly journals Response of chemical and microbial properties to short-term biochar amendment in different agricultural soils

2020 ◽  
pp. 61-69
Author(s):  
Milorad Zivanov ◽  
Srdjan Seremesic ◽  
Dragana Bjelic ◽  
Jelena Marinkovic ◽  
Jovica Vasin ◽  
...  
Keyword(s):  
Agricultural Soils ◽  
Triticum Aestivum L ◽  
Low Fertility ◽  
Total Carbon ◽  
Short Term ◽  
Microbial Properties ◽  
Applied Dose ◽  
Higher Doses ◽  
Biochar Amendment ◽  
Copiotrophic Bacteria

The objective of this study was to assess the effect of biochar soil amendment (BSA) on chemical and microbial properties in different agricultural soils in Vojvodina Prov?ince. Short-term pot experiment consisted of five biochar application doses (0, 0.5, 1, 2, and 3%) and five contrasting soil types (Mollic Gleysol, Eutric Cambisol, Calcaric Fluvisol, Gleyic Chernozem, and Haplic Chernozem), planted with sunflower (Helianthus annuus L.) and winter wheat (Triticum aestivum L.). The examined chemical and microbial properties were significantly influenced by soil type and interaction of experimental factors. Significant influence of biochar on the contents of calcium carbonate (CaCO3), total nitrogen (N), total carbon (C), soil organic carbon (SOC), humus and potassium (K) of the tested soils was observed. Biochar also significantly affected the number of azotobacters (AZB), fungi (FNG), actino?mycetes (ACT) and copiotrophic bacteria (CB). The effect of BSA varied depending on the applied dose, with higher values of the examined chemical and microbial parameters at higher doses of application. Further studies on using biochar in soils with low fertility will be neces?sary to establish its efficiency as an enhancer for agricultural production in Serbia.

scholarly journals Multiple quality tests for analysing CO<sub>2</sub> fluxes in a beech temperate forest

2007 ◽  
Vol 4 (6) ◽  
pp. 4197-4228
Author(s):  
B. Longdoz ◽  
P. Gross ◽  
A. Granier
Keyword(s):  
Climatic Factors ◽  
Net Ecosystem Exchange ◽  
Co2 Flux ◽  
Vegetation Pattern ◽  
Quality Data ◽  
Night Time ◽  
Complete Evaluation ◽  
Assessment Tests ◽  
Data Gap ◽  
A Site

Abstract. The eddy covariance (EC) measurements are widely used to estimate the amount of carbon sequestrated by terrestrial biomes. The data quality and the selection of the correct EC records become an important step in the CO2 flux determination procedure. In this paper an innovative combination of existing assessment tests is used to give a relatively complete evaluation of the net ecosystem exchange measurements. For the 2005 full-leaf season at the Hesse site, the percentage of bad quality data is relatively high (59.6%) especially during night-time (68.9%). This result strengthens the importance of the data gap filling method. The filtering used does not lead to a real improvement of the accuracy of the relationship between the CO2 fluxes and the climatic factors. The soil respiration spatial heterogeneity (on a site with relatively homogenous vegetation pattern) seems to be too important to allow this improvement. However, the data rejected present some common characteristics. Their removal lead to a 10% increase in the total amount of CO2 respired and photosynthesised during the 2005 full-leaf season. Consequently the application of our combination of multiple quality tests is able improve the inter-annual analysis. The question of a systematic application on the large database like the CarboEurope and FLUXNET is legitimate.

Fertility investigations on the black earth wheatlands of the Darling Downs, Queensland. I. Moisture accumulation under short fallow

1958 ◽  
Vol 9 (2) ◽  
pp. 205 ◽  
Author(s):  
SA Waring ◽  
WE Fox ◽  
LJH Teakle
Keyword(s):  
Surface Soil ◽  
Climatic Factors ◽  
Clay Content ◽  
High Moisture ◽  
Total Rainfall ◽  
Soil Layers ◽  
Significant Difference ◽  
Winter Crops ◽  
Instance Correlations ◽  
Summer Fallow

The accumulation of soil moisture during the period of summer fallow between successive winter crops of wheat has been examined for a number of localities on the Darling Downs, and for the seasons 1951-1954. The moisture gain to a depth of 4 ft between the harvest of one crop and the planting of the succeeding crop ranged from – 0.3 to 5.0 in., with an average of 2.2 in. representing 17 per cent. of the rainfall. Available moisture at planting averaged 4.8 in., the excess of 2.6 in. over fallow gain being due to the available moisture already in the soil at the preceding harvest. In this locality, therefore, moisture accumulation commonly occurs prior to harvest, owing to rainfall in excess of crop requirements at this period. The average values for available moisture at planting mere well below the capacity of these soils for storage to 4 ft. Values following long fallow averaged 6.5 in., and were as high as 9.9 in. in one instance. Correlations have been sought between fallow moisture gain and available moisture at planting, and the associated soil and climatic factors. The more important findings were : (1) Total rainfall during the fallowing period was not correlated with fallow moisture gain. (2) Fallow moisture gain and available moisture at planting were correlated with March-April rain. (3) Fallow moisture gain was correlated negatively with available moisture at the preceding harvest and positively with available moisture at planting. (4) The clay content of the soil and depth of surface mulch were not significantly related to fallow moisture gain nor to available moisture at planting. (5) No significant difference in moisture accumulation was observed between sites stubble-mulched and those stubble-burnt. Explanations in terms of climatic and soil characteristics are offered for the results obtained. Features considered important are the characteristics of the rainfall and the high-evaporation conditions, the low rate of moisture penetration in wet soil, and the high moisture-holding capacity of the surface soil layers.

Soil water conservation under cultivated fallows in clay soils of south-western Queensland

1976 ◽  
Vol 16 (81) ◽  
pp. 564 ◽  
Author(s):  
AJ Pressland ◽  
GN Batianoff
Keyword(s):  
Soil Moisture ◽  
Soil Water ◽  
Water Conservation ◽  
Field Experiments ◽  
Crop Yields ◽  
Early Summer ◽  
Forage Crop ◽  
Deep Profile ◽  
A Site ◽  
Summer Fallow

Three field experiments to study the effect of time and method of cultivation during fallow on soil moisture accretion and crop growth were established at a site near Charleville, Queensland. The soil was a grey-brown cracking clay (46 per cent clay) typical of the Mitchell grass (Astrebla spp.) downs. In the first experiment, soil moisture accretion was followed on plots cultivated in November 1966 with either a disc plough or scarifier or not cultivated. Soil moisture was increased in the 90 cm deep profile by cultivation, but remained almost constant for the duration of the summer fallow. There was no difference in soil moisture under the disced and scarified plots. The remaining experiments were designed to study the effect of cultivations during fallow on soil moisture at the time of sowings. One early summer cultivation resulted in soil moisture levels similar to that gained from two or more ploughings. However, crop yields were highest following three cultivations. It is concluded that two or three cultivations during fallow decreases loss of soil water through transpiration of weeds and should increase the number of years a forage crop can be expected in south western Queensland.

FIXATION AND RELEASE OF Cs-137 IN SOILS AND SOIL SEPARATES

1966 ◽  
Vol 46 (3) ◽  
pp. 217-222 ◽  
Author(s):  
E. J. Evans ◽  
A. J. Dekker
Keyword(s):  
Large Range ◽  
Agricultural Soils ◽  
Clay Fraction ◽  
Alkaline Soils ◽  
Sand Fraction ◽  
Podzolic Soils ◽  
Carrier Free ◽  
Applied Dose ◽  
Series Of Experiments ◽  
The Difference

In a series of experiments designed to describe Cs fixation and release by soils and sou separates, considerable Cs-137 was found to be fixed by the sand fractions of agricultural soils. The amount fixed by the sand exceeded that fixed by the clay m calcium-saturated samples taken from Podzolic soils. Cesium fixed when added as CsCl in macroconcentrations (5 meq per 100-g sample) was greater in the clay fractions than the sand fractions for all soils. These findings support the findings of others that there is more than one site for CS fixation depending on the concentration. Considerable Cs-137 was released by soil separates when shaken in the presence of H-resin. The amount released by the sand fraction was substantially greater than that released by the clay fraction for two of the three soils investigated. The fixation of Cs-137 was found to be approximately proportional to applied dose over a large range of carrier-free Cs-137 concentrations. The amount fixed by soils of alkaline pH was higher than that fixed by samples from Podzolic soils at all concentrations. When the soils were calcium-saturated after the removal of the colloidal sesquioxides by oxalate extractions, the difference between the fixation of Cs-137 by acid and alkaline soils was greatly decreased. This suggests strongly that these colloidal coatings blocked Cs-137 fixation by Podzolic soils.

Sign in / Sign up

Export Citation Format

Share Document