scholarly journals Leaching of fluridone, hexazinone and simazine in sandy soils in the Netherlands.

1989 ◽  
Vol 37 (3) ◽  
pp. 257-262
Author(s):  
R. Zandvoort
Keyword(s):  
The Netherlands ◽  
Field Experiments ◽  
Sandy Soils ◽  
Coarse Sand ◽  
Transformation Rate ◽  
Soil Layers ◽  
Late Autumn ◽  
Winter Conditions

Fluridone and simazine were sprayed in field experiments on coarse and humic sandy soils in spring or in late autumn, and hexazinone on coarse sand in spring. After a spring application, over an eight-month period, fluridone and hexazinone were detected by bioassay in the profile of coarse sand from 0 to 60 cm, whereas simazine did not leach below 15 cm. Both fluridone and simazine were found to a depth of 60 cm in coarse sand after an application in late autumn. Thus, in winter conditions the transformation rate is not fast enough to prevent leaching of fluridone and simazine to deeper soil layers after autumn application. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Factors influencing the sodium content of meadow grass.

1965 ◽  
Vol 13 (1) ◽  
pp. 21-47
Author(s):  
C.H. Menkens
Keyword(s):  
The Netherlands ◽  
Sandy Soils ◽  
Sodium Content ◽  
Clay Soils ◽  
N Fertilizers ◽  
Factors Influencing ◽  
High Soil ◽  
Fertilizer Recommendations ◽  
Soil K Status ◽  
Mg Content

Sodium content of grass was largely determined by Na content and K number of the soil. At a given Na content of soil, the Na content of grass decreased with increasing K number of the soil but the decrease was small where K number was >30. Na content of grass increased with increasing soil Na; the increase was higher at low- than at high soil-K status. K fertilizing lowered grass Na at low soil-K status. Soil-Na content can be used in the Netherlands as a basis for Na-fertilizer recommendations, since K number has generally reached a level at which it has an almost constant effect on Na content of grass. Influences of the K and Na status of the soil on the Na content of grass can be expressed as the ratios (15 X K number)/(Na2O+6) for sandy soils and (25X K number)/(Na2O + 14) for clay soils, the numerator at K numbers > 30 being the same as that at K number=30. With increasing ratios, the Na content of grass decreases. The influence on herbage -Na level of a given amount of Na in K fertilizers is correlated to these ratios. The influence of N fertilizers on Na content of grass was not clear and the influence of Mg fertilizers was negligible. Chile nitrate and Nad affected the Na of grass similarly, but Chile nitrate differed from NaCl in decreasing the Ca content; both fertilizers slightly lowered the Mg content of grass. Herbs and clovers contained more Na than grass does. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Measuring thermal conductivity of soils under laboratory conditions.

1969 ◽  
Vol 17 (1) ◽  
pp. 71-79
Author(s):  
A.I. Golovanov
Keyword(s):  
Thermal Conductivity ◽  
Flow Velocity ◽  
Soil Sample ◽  
Water Flow ◽  
Coarse Sand ◽  
Conductivity Measurements ◽  
Soil Layers ◽  
The Real ◽  
Real Flow

Experiments were made to determine the influence of size of soil sample, convection and water flow on the determination of thermal conductivity of soils using a thin needle (0.05 cm radius, 8.5 cm in length) as the heating element and copper cylinders for sample containers. For measurements during a period of 100 seconds the diameter of the sample must be at least 4 cm and to avoid any influence of convection measurements should not exceed 100 seconds. When heating elements are placed horizontally to measure simultaneously the thermal conductivity of different soil layers they should be placed at least 10 cm apart. Thermal conductivity measurements could be used to determine flow velocities of water in coarse sand samples provided that the real flow velocity was highev than 0.35 cm/ min. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Nitrogen dressing and nutrient absorption of lilies (Asiatic hybrids) on sandy soils.

1989 ◽  
Vol 37 (3) ◽  
pp. 269-272
Author(s):  
J.H.G. Slangen ◽  
G.J. Krook ◽  
C.H.M. Hendriks ◽  
N.A.A. Hof
Keyword(s):  
Nutrient Uptake ◽  
Field Experiments ◽  
N Uptake ◽  
Sandy Soils ◽  
Plant Analysis ◽  
Split Application ◽  
Total N ◽  
N Efficiency ◽  
Asiatic Hybrids ◽  
Bulb Yield

The effect of different amounts (0, 75, 150 and 225 kg/ha) and timings of split application of N on yield and nutrient uptake of 3 hybrid cultivars grown for bulbs was investigated. Efficiency of N-uptake was determined by soil and plant analysis with field experiments in 1983, 1984 and 1985. Leaching of fertilizers applied before planting induced low nutrient efficiencies in sandy soils. Dividing the total N-dressings into 4 monthly applications from Mar. to June or Apr. to July led to a higher N-efficiency, though fertilizers were easily leached with high rainfall. A total of 150 kg N/ha appeared to be adequate. Concentrations of plant nutrients (P, K, Ca, Mg and Na) in mature plants of cultivars Aristo, Connecticut King and Enchantment are presented in relation to bulb yield and N-uptake. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Effects of the use of drainage-/ infiltration systems in the Pleistocene uplands of the Netherlands

2021 ◽  
Author(s):  
Janine A. de Wit ◽  
Ruud P. Bartholomeus ◽  
Gé A.P.H. van den Eertwegh ◽  
Marjolein H.J. van Huijgevoort
Keyword(s):  
Waste Water ◽  
The Netherlands ◽  
Boundary Conditions ◽  
Water Supply ◽  
Field Experiments ◽  
Crop Yields ◽  
Scale Model ◽  
Groundwater System ◽  
External Water ◽  
The Impact

<p>The Netherlands is a low-lying, flood prone country, located in a delta. Most Dutch agricultural fields are drained to quickly get rid of excess water to increase crop production. Additionally, the freshwater demand of different sectors (agriculture, industry, drinking water) increases, causing an increased pressure on the groundwater system. The combination of fast drainage and increased use of groundwater for human activities led to declining groundwater tables in the Dutch Pleistocene uplands. Given the changing climate resulting in prolonged dry periods, solutions for water retention are needed to decrease the pressure on the groundwater system to guarantee the future water supply for different sectors.</p><p>One of the solutions could be to modify the current drainage systems to drainage-infiltration (DI)-systems with a dual purpose. First, the DI-system stores water during (heavy) rainfall in the soil, but if the risk of flooding increases, the DI-system discharges water. Second, (external) water is actively pumped into the drainage network to raise groundwater tables (subirrigation). Through efficient use of the available external water source (treated waste water, industrial waste water, surface water or groundwater) the pressure on the groundwater system reduces.</p><p>We focus on the data and model results of several field experiments using subirrigation conducted in the Dutch Pleistocene uplands (± 2017-2020). The effects of subirrigation on the groundwater table and soil moisture conditions will be shown, including water supply rate and hydrological boundary conditions. We also provide both the set-up and results of field scale model simulations (SWAP; Soil-Water-Atmosphere-Plant model) to i) quantify the impact of subirrigation on all components of the (regional) water balance (including transpiration, drainage and groundwater recharge), ii) quantify crop yields, and iii) optimize the configuration and management of subirrigation systems for different soil types, hydrological boundary conditions, and climate scenarios.  </p>

SEASONAL VARIATION IN THE COMPOSITION OF THE BACTERIAL SOIL FLORA IN RELATION TO PLANT DEVELOPMENT

1957 ◽  
Vol 3 (2) ◽  
pp. 131-134 ◽  
Author(s):  
H. G. Gyllenberg
Keyword(s):  
Seasonal Variation ◽  
Plant Development ◽  
Bacterial Population ◽  
Field Experiments ◽  
Soil Surface ◽  
Growth Season ◽  
Soil Layers ◽  
Rhizosphere Population ◽  
In The Beginning

In field experiments with oats the composition of the bacterial population in the rhizosphere was found to be almost stable during the whole period of plant development from young seedlings to maturity. In the beginning of the growth season the soil flora was quite different from that of the rhizosphere. It was, however, successively changed, and became, toward the end of the season, similar in composition to the rhizosphere population. This change proceeded from the soil surface into deeper soil layers, and it can be concluded that it was due to the development of roots, and to a migration of bacteria from the rhizosphere into the soil.

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