The effect of preferential flow of dairy cow urine and simulated rainfall on movement of potassium through undisturbed topsoil cores

Soil Research ◽  
1990 ◽  
Vol 28 (6) ◽  
pp. 857 ◽  
Author(s):  
PH Williams ◽  
MJ Hedley ◽  
PEH Gregg

Cores of undisturbed topsoil (15 cm in depth and diameter) were taken from a range of soil types to a controlled climate chamber. Urine from dairy cows was spiked with tritiated water (3H2O) and then applied to these cores which had moisture contents near field capacity. Liquid draining from these cores, as a direct consequence of urine application, contained up to 72% of the tritiated water, 74% of the potassium (K), 62% of the nitrogen (N) and 80% of the chloride (Cl) applied in the urine, indicating that urine could flow preferentially beyond the 15 cm depth in these soils. The activity of tritium and the concentrations of K, N and Cl in the effluent indicated that this preferential movement of urine occurred too quickly for sorption reactions to occur between the soil surface and the majority of solutes in the urine. After preferential flow had ceased, the amounts of K leached by subsequent simulated rain events were much smaller than losses immediately following the urine application. Leaching losses were particularly small (accounting for 3-15% of the applied urine K) when the majority of the rain water moved preferentially through the soil cores, thus bypassing the urine K which was in soil micropores or which had been sorbed by the soil. Overall, these results suggest that substantial movement of K (and N) through the topsoil of grazed pastures may occur following a urination event due to preferential flow of dairy cow urine through the soil profile, at least when soils are near field capacity at the time of urine deposition. The extent of this movement through topsoil will be more dependent upon soil structural characteristics rather than soil chemical characteristics.

2020 ◽  
Vol 15 (1) ◽  
pp. 93-102
Author(s):  
Cristian PĂLTINEANU ◽  
◽  
Andrei VRINCEANU ◽  
Anca-Rovena LĂCĂTUȘU ◽  
Radu LĂCĂTUŞU ◽  
...  

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 ◽  
...  

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.


2016 ◽  
Vol 20 (1) ◽  
pp. 45-50
Author(s):  
S Akter ◽  
S Pervin ◽  
KM Iftekharuddaula ◽  
A Akter ◽  
R Yasmeen

Due to over sinking of underground water, scarcity of irrigation water is becoming a threat to the sustainability of irrigated rice production and the concept of aerobic culture appeared prominently. Aerobic rice has the ability to grow under minimum irrigation water and minimum yield reduction occurs when grown under aerobic culture with less water. This experiment aimed to evaluate two advanced aerobic rice lines under transplanted condition in net house. Two advanced lines, IR83140-B-36-B-B and IR83142-B-71-B-B and two check varieties BRRI dhan28 and BRRI dhan29 were grown in three moisture regimes. The moisture regimes included a) continuous standing water (CSW) b) saturated moisture condition (SMC) and c) moisture content at field capacity (FCM). The experimental units, drum containing 110 kg soil, were arranged in randomized complete block design (RCBD) with five replications. Three to four seedlings of forty days were transplanted at the soil surface of each drum. Seedlings were thinned to one plant per genotypes one week after transplanting. Genotype × water interaction showed significant variation in total dry matter production, panicle length, panicle exertion rate, sterility percentage and yield contributing characters. Irrespective of the genotypes, CSW conditions favored to produce maximum number of tiller and panicle. Although BRRI dhan29 gave the highest yield at both CSW and SMC, IR83142-B-71-B-B produced the highest yield at FCM. However, BRRI dhan28 gave similar yield to that of IR83142-B-71-B-B in FCM treated drums.Bangladesh Rice j. 2016, 20(1): 45-50


2008 ◽  
Vol 16 (3) ◽  
pp. 267 ◽  
Author(s):  
K. RASA ◽  
R. HORN ◽  
M. RÄTY

Water repellency (WR) delays soil wetting process, increases preferential flow and may give rise to surface runoff and consequent erosion. WR is commonly recognized in the soils of warm and temperate climates. To explore the occurrence of WR in soils in Finland, soil R index was studied on 12 sites of different soil types. The effects of soil management practice, vegetation age, soil moisture and drying temperature on WR were studied by a mini-infiltrometer with samples from depths of 0-5 and 5-10 cm. All studied sites exhibited WR (R index >1.95) at the time of sampling. WR increased as follows: sand (R = 1.8-5.0) < clay (R = 2.4-10.3) < organic (R = 7.9-undefined). At clay and sand, WR was generally higher at the soil surface and at the older sites (14 yr.), where organic matter is accumulated. Below 41 vol. % water content these mineral soils were water repellent whereas organic soil exhibited WR even at saturation. These results show that soil WR also reduces water infiltration at the prevalent field moisture regime in the soils of boreal climate. The ageing of vegetation increases WR and on the other hand, cultivation reduces or hinders the development of WR.;


1988 ◽  
Vol 14 (2P2B) ◽  
pp. 1231-1234 ◽  
Author(s):  
Y. Belot ◽  
J. Guenot ◽  
C. Caput
Keyword(s):  

Weed Science ◽  
1973 ◽  
Vol 21 (5) ◽  
pp. 469-473 ◽  
Author(s):  
J. V. Parochetti ◽  
E. R. Hein

Vapor losses of trifluralin (α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine), benefin (N-butyl-N-ethyl-α,α,α-trifluoro-2,6-p-toluidine), and nitralin [4-(methylsulfonyl)-2,6-dinitro-N,N-dipropylaniline] were studied under controlled laboratory conditions using a Florisil vapor trap. No nitralin vapor losses were detected at 50 C from a Lakeland loamy sand at field capacity with an air flow rate of 0.04 m3/hr for 3 hr; whereas, 24.5% and 12.5% of trifluralin and benefin, respectively, were lost as vapors. Volatility of trifluralin and benefin increased with increasing temperatures of 30, 40, and 50 C and increasing soil moisture from air dryness to field capacity. Vapor losses from granular benefin were similar to the spray applications at 30 and 40 C. Volatilization of granular trifluralin was reduced when compared to the spray application at 40 C and 30 C but was similar for both formulations for benefin. No significant losses from photodecomposition were noted for trifluralin, benefin, or nitralin when comparing radiated and unradiated soil surface treated samples.


Soil Research ◽  
1998 ◽  
Vol 36 (6) ◽  
pp. 963 ◽  
Author(s):  
R. E. White ◽  
L. K. Heng ◽  
G. N. Magesan

Nitrate (NO-3 ) concentrations in 0·5-mm increments of drainage from adjacent mole- and pipe-drained paddocks of a silt loam soil under pasture near Palmerston North, New Zealand, were measured during 2 winters. The data were simulated using a simple analytical transfer function model (TFM). Urea fertiliser applied at the rate of 120 kg N/ha to one paddock was treated as a pulse input to the pool of resident soil NO-3. A source{sink term was included for plant uptake and net mineralisation (including any effect of denitrification). During the first winter (1990), a TFM using either a 1-parameter Burns probability density function (pdf) for solute travel, or a 2-parameter lognormal pdf, satisfactorily simulated the NO-3 concentration trends and predicted the total amounts of N leached. The pdf parameters were derived from previous chloride leaching data for this site. The best-fit value for the transport volume θst, the key parameter in the Burns pdf, was set at 0·37 m3 /m3 in 1990, as used in previous modelling of sulfate leaching. However, a value of 0 ·25 m3 /m3 in the Burns pdf gave better simulations of the 1991 data. This was probably due to more intense rain events during the early part of the drainage season in 1991 compared with 1990, which resulted in more preferential flow through the soil and a lower value for θst. The simulations for both years showed that ≥50% of the total leachable NO-3 was retained in the soil, despite normal winter drainage of about 300 mm. Ideally, the appropriate value of st should be determined by independent measurement. It may need to be adjusted according to the likely incidence of preferential flow early in the winter when NO-3 concentrations are highest. Provided the average initial soil NO-3 concentration can be estimated and a net source{sink term defined, the amount of NO-3 leached in drained soils can be satisfactorily modelled using the TFM approach with a 1-parameter pdf. Duplex soils which have a fluctuating watertable in the A horizon over an impermeable B horizon may prove to be an analogous system.


Soil Research ◽  
1995 ◽  
Vol 33 (6) ◽  
pp. 1031
Author(s):  
HJ Di ◽  
RS Kookana ◽  
LAG Aylmore

A simple model is described for assessing the ground water contamination potential of pesticides. This model, based on simple processes of linear, equilibrium and singular partition between solution and soil organic matter, steady convective flow, and first-order degradation, calculates fractions of pesticides remaining in the soil as they leach to greater depth. Possible effects by preferential flow that may be present in structured soils are ignored. The soil profile is divided into a number of layers which may differ in bulk density, moisture content at field capacity, organic C content, and degradation half-life. The leaching depths predicted by this model generally agreed with the mean leaching depths measured in a field study, and with those predicted by the CALF model. The leaching depths by the simple model were also statistically related to those simulated by the LEACHM model, although the values by LEACHM were found to be much higher than those by the simple model and by CALF. Under the soil and environmental conditions given, the simple model predicted that chlorpyriphos and chlorthal dimethyl would not leach to any noticeable depth before being completely degraded, that metribuzin, prometryne, propyzamide and simazine would mostly degrade to insignificant concentrations before reaching 500 cm, and that traces of fenamiphos, metalaxyl and linuron might reach beyond 1000 cm.


Soil Research ◽  
2008 ◽  
Vol 46 (1) ◽  
pp. 76 ◽  
Author(s):  
H. J. Di ◽  
K. C. Cameron

A field lysimeter study was conducted to determine the sources of N2O emitted following the application of dairy cow urine and urea fertiliser labelled with 15N, with and without a nitrification inhibitor, dicyandiamide (DCD). The results show that the application of cow urine at 1000 kg N/ha significantly increased N2O emissions above that from urea applied alone at 25 kg N/ha. The application of urine seemed to have a priming effect, increasing N2O emissions from the soil N pool. Treating the soil with DCD significantly (P < 0.05) decreased N2O emissions from the urine-applied treatment by 72%. The percentage of N2O-N derived from the applied N was 53.1% in the urine-applied treatment and this was reduced to 29.9% when DCD was applied. On average, about 43% of the N2O emitted in the urine-applied treatments was from nitrification. The application of DCD did not have a major effect on the relative contributions of nitrification and denitrification to N2O emissions in the urine treatments. This indicates that the DCD nitrification inhibitor decreased the contributions to N2O emissions from both nitrification and denitrification.


2020 ◽  
Author(s):  
Elena Zubieta ◽  
Juan Larrasoaña ◽  
Rafael Giménez ◽  
Alaitz Aldaz ◽  
Javier Casalí

&lt;p&gt;In gully erosion, the soil detached by the action of the erosive flow can be transported over long distances along the drainage network of the watershed. In this long way, the eroded material can be redistributed and/or deposited on the soil surface, and then eventually buried by eroded material from subsequent erosion events. Likewise, the variability of the soil (i.e., in texture and moisture content) over which this material moves can be considerable. The presence of the eroded material could be detected through magnetic tracers attached/mixed with the eroded soil. In this experiment, the degree to which the magnetic signal of the magnetite is conditioned by (i) the burying tracer depth, (ii) the texture and moisture content of the soil covering the tracer and (iii) the tracer concentration was evaluated.&lt;/p&gt;&lt;p&gt;The study was carried out in the lab in different containers (0.5 x 0.5 x 0.3 m&lt;sup&gt;3&lt;/sup&gt;). Each container was filled with a given soil. In the filling process, a 0.5-cm layer of a soil-magnetite mixture of a certain concentration was interspersed in the soil profile at a certain depth. Overall, 3 different soil:tracer concentrations (1000:1, 200:1, 100:1), 4 tracer burying depths (0 cm, 3 cm, 5 cm and 10 cm from soil surface), and &amp;#160;2 contrasting soils (silty clay and sandy clay loam) were used. In each case, the magnetic susceptibility was measured with a magnetometer (MS3 by Bartington Instruments). Experiments were repeated with different soil moisture contents (from field capacity to dry soil).&lt;/p&gt;&lt;p&gt;If the tracer is located under the soil surface a minimum soil:tracer concentration of 200:1 is required for its correct &amp;#160;detection from the surface using a magnetometer. The intensity of the magnetic signal decreases dramatically with the vertical distance &amp;#160;of the tracer from the soil&amp;#160; surface (burying depth). The maximum detection depth of the tracer magnetic signal is strongly dependent on the natural magnetic susceptibility of the soil which hides the own tracer signal. Variation in soil moisture content does not significantly affect the magnetic signal. For extensive field studies the soil-tracer volume to be handled would be very high. Therefore, it is necessary to explore new tracer application techniques.&lt;/p&gt;


Sign in / Sign up

Export Citation Format

Share Document