VARIABILITY IN SOIL MOISTURE SAMPLING

1962 ◽  
Vol 42 (1) ◽  
pp. 157-164 ◽  
Author(s):  
W. J. Staple ◽  
J. J. Lehane
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Early Spring ◽  
Frozen Soil ◽  
Sampling Location ◽  
Low Permeability ◽  
Moisture Determination ◽  
Paired Samples ◽  
Small Plot

The standard deviation of soil moisture content in 4-foot profiles of Wood Mountain clay loam at seedtime varied from 0.6 to 1.3 inches. The variability changed from year to year and to some extent from season to season, depending on weather and cropping conditions. Low permeability of partially frozen soil during periods of rapid thaw in early spring was a major factor influencing variability.Choice of sampling location was important in experimental work. The variability was minimized on areas of uniform soil texture and on nearly level well-drained topography. The use of paired samples from adjacent sites reduced the error when changes in moisture content were measured with respect to time or treatment.Six to ten samples from small plot areas may be adequate for moisture determination in many types of experiment. On the other hand, for more precise work thirty samples or more would be required per treatment to provide fair assurance that the LSD between the means of two treatments be less than 0.5 inch of water.

EFFECTS OF IRRIGATION AND NITROGEN ON A NATURAL PASTURE SWARD

1978 ◽  
Vol 58 (2) ◽  
pp. 347-356
Author(s):  
W. N. BLACK
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Sandy Loam ◽  
Field Capacity ◽  
Early Spring ◽  
Naturally Occurring ◽  
Natural Pasture ◽  
Loam Soil ◽  
Grazing Period

Irrigation and nitrogen (N) requirements of a natural pasture sward were studied on a Charlottetown sandy loam soil over a 5-yr period. The soil moisture content at the 0-to 15- and 15- to 30-cm depths was determined at from 7- to 10-day intervals, while irrometer soil moisture readings at 15-, 30-, and 45-cm depths were recorded more frequently during the grazing seasons. Soil moisture content in irrigated plots averaged 92 and 94% of field capacity, respectively, at 0- to 15- and 15- to 30-cm sampling depths. In non-irrigated plots, corresponding values were 77 and 82%. N treatments resulted in significant dry matter (DM) increases over untreated plots. Yield differences among plots receiving 56, 84, and 112 kg of N/ha in mid-June and again in mid-August were not significant. Early spring and September applications of N at 56 kg/ha, combined with mid-June and early August supplements of N at 84 kg/ha were superior to all other treatments in prolonging the grazing period. Neither irrigation nor N affected the characteristic yield decline of naturally occurring forage species in mid- and late-season. Mean DM production for the 5-yr period, and for years, showed no significant N treatment × moisture level interaction. While irrigation failed to increase yields significantly, livestock preferred to graze the irrigated plots. As a result of less competition from grasses, volunteer white clover became better established, and constituted a larger percentage of the sward than on non-irrigated plots.

scholarly journals Design and Construction of a Soil Moisture Measuring

2020 ◽  
pp. 29-34
Author(s):  
A. A. Ijah ◽  
O. W. Bolaji ◽  
O. O. Adedire ◽  
J. Z. Emmanuel ◽  
N. E. Onwuegbunam ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Regression Coefficient ◽  
Gravimetric Method ◽  
Voltage Regulator ◽  
Moisture Determination ◽  
Moisture Contents ◽  
Design And Construction

A digital soil moisture reader was constructed and tested. It uses a lipo battery of 9v which was regulated to a constant 5v with the help of a voltage regulator 7805. The digital soil moisture reader developed was tested and the result obtained was compared with that obtained using the gravimetric method of determining soil moisture contents. In determining the soil moisture content, a certain quantity of soil was collected and a particular volume of water was added incrementally. The result shows that the soil moisture reader is accurate. The evaluation was carried out using the gravimetric method of soil moisture determination as a basis of comparison. Nine samples of 50g of soli were collected from Federal College of Forestry Mechanization Farm and a certain amount of water was added incrementally during the process of determining the soil moisture content. The soil reader was calibrated using the gravimetric method which shows a regression coefficient R^2 of 0.986 which indicates that the soil reader is accurate, sensitive and reliable.

scholarly journals Simulated and In Situ Frost Heave in Seasonally Frozen Soil from a Cold Temperate Broad-leaved Korean Pine Forest

2016 ◽  
Author(s):  
Maosen Lin ◽  
Anzhi Wang ◽  
Dexin Guan ◽  
Changjie Jin ◽  
Jiabin Wu ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Empirical Relationship ◽  
Pine Forest ◽  
Frozen Soil ◽  
Frost Heave ◽  
Korean Pine ◽  
Korean Pine Forest

Frost heave, which is the volumetric expansion of frozen soil, has great ecological significance, since it creates water storage spaces in soils at the beginning of the growing season in cold temperate forests. To understand the characteristics of frost heave in seasonally frozen soil and the factors that impact its extent, we investigated the frost heave rates of forest soil from different depths and with different soil moisture contents, using both lab-based simulation and in situ measurement in a broadleaved Korean pine forest in the Changbai Mountains (northeastern China). We found that frost heave was mainly affected by soil moisture content, soil type, and gravitational pressure. Frost heave rate increased linearly with soil moisture content, and for each 100% increase in soil moisture content, the frost heave rate increased by 41.6% (loam, upper layer), 17.2% (albic soil, middle layer), and 4.6% (loess, lower layer). Under the same soil moisture content, the frost heave rate of loam was highest, whereas that of loess was lowest, and the frost heave of the uppermost 15 cm, which is the biologically enriched layer, accounted for ~55% of the frost heave. As a result, we determined the empirical relationship between frost heave and freezing depth, which is important for interpreting the effects of frost heave on increases in the storage space of forest soils and for calculating changes in soil porosity.

Impact of Fall and Early Spring Herbicide Applications on Insect Injury and Soil Conditions in No-Till Corn

2007 ◽  
Vol 21 (4) ◽  
pp. 1002-1009 ◽  
Author(s):  
Nicholas Monnig ◽  
Thomas L. Clark ◽  
Wayne C. Bailey ◽  
Kevin W. Bradley
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Temperature ◽  
Soil Moisture Content ◽  
Flea Beetle ◽  
Early Spring ◽  
Soil Conditions ◽  
Weed Species ◽  
No Till ◽  
Annual Weeds

Field studies were established at two Missouri locations in 2004 and 2005 to evaluate the effects of fall and early spring herbicide applications on soil temperature, soil moisture content, and insect injury in no-till corn production systems. Both experiments received applications of simazine plus 2,4-D, rimsulfuron plus thifensulfuron plus 2,4-D, and glyphosate plus 2,4-D in the fall, 45 d prior to planting (45 d EPP), 30 d prior to planting (30 d EPP), and 7 d prior to planting (7 d EPP). During a period from April 1 to April 14, simazine plus 2,4-D applied 45 d EPP resulted in higher soil temperatures at a 5-cm depth compared to the untreated control. However, there were few differences in soil temperature present from April 15 to May 1. Soil moisture readings taken during this same time period correlated with soil temperature readings. Measurements of soil moisture taken at 1 and 3 wk after planting (WAP) revealed significantly lower soil moisture readings in the untreated compared to herbicide treated plots. This lower soil moisture content allowed untreated plots to warm up more rapidly and thereby eliminated any negative impacts that dense stands of winter annual weeds may have had on soil temperature. Evaluations of corn flea beetle and lepidopteron injury taken at the V2, V4, and V6 corn leaf stages revealed significant differences in injury as a result of these treatments. When dense stands of winter and summer annual weeds were left uncontrolled, corn flea beetle injury was significantly lower than in plots treated with a herbicide. However, when a post herbicide application was made to remove all weed species prior to the V6 sampling date, differences in corn flea beetle injury between the untreated and herbicide treated plots were eliminated. Additionally, removal of all weed species led to higher lepidopteron injury in the untreated.

Soil Moisture Research of Revegetation Area on Slop of Yingrui Highway in the Spring

2011 ◽  
Vol 356-360 ◽  
pp. 2440-2444
Author(s):  
Chun Ying Long
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Dynamic Monitoring ◽  
Moisture Determination ◽  
Drying Method ◽  
Deep Soil ◽  
Oven Drying ◽  
Rocky Slope ◽  
Reconstruction Mode

The research object is slop near Yingrui highway, we mainly used oven drying method, combined with TDR, carrying out different vegetation types in interchange area and different substrates types in slope area about dynamic monitoring soil moisture in the spring. According to the result, The daily dynamic of the 2 types of slop soil moisture content has no obvious regular pattern, but each time the moisture content in soil slope are higher than rocky slope. We can get the conclusion after variance analysis, the main factors which influencing the discretion of the soil moisture content in slope and interchange area are the slope matrix type and the different vegetation reconstruction mode in interchange area. Meanwhile, according to the data, which we applied to the same experiment with both TDR and oven drying method, and after comparative analysis, we think, it’s completely effective to make TDR applied in deep soil moisture determination in some places such as interchange area, but the data about shallow soil moisture determination which got from the places such as in side slope is inaccurate. We should be more cautious when using it.

Analysis on Soil Moisture Content in the Middle Reaches of the Yellow River

2011 ◽  
Vol 28 (1) ◽  
pp. 85-91 ◽  
Author(s):  
Run-chun LI ◽  
Xiu-zhi ZHANG ◽  
Li-hua WANG ◽  
Xin-yan LV ◽  
Yuan GAO
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Yellow River ◽  
The Yellow River

Distribution of soil moisture content and its effect on the potential growth of the over-story species in North-East Chalkidiki

2001 ◽  
Vol 66 ◽  
Author(s):  
M. Aslanidou ◽  
P. Smiris
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Soil Depth ◽  
Moisture Distribution ◽  
Taxus Baccata ◽  
Mixed Stands ◽  
Potential Growth ◽  
North East ◽  
Soil Moisture Distribution

This  study deals with the soil moisture distribution and its effect on the  potential growth and    adaptation of the over-story species in north-east Chalkidiki. These  species are: Quercus    dalechampii Ten, Quercus  conferta Kit, Quercus  pubescens Willd, Castanea  sativa Mill, Fagus    moesiaca Maly-Domin and also Taxus baccata L. in mixed stands  with Fagus moesiaca.    Samples of soil, 1-2 kg per 20cm depth, were taken and the moisture content  of each sample    was measured in order to determine soil moisture distribution and its  contribution to the growth    of the forest species. The most important results are: i) available water  is influenced by the soil    depth. During the summer, at a soil depth of 10 cm a significant  restriction was observed. ii) the    large duration of the dry period in the deep soil layers has less adverse  effect on stands growth than in the case of the soil surface layers, due to the fact that the root system mainly spreads out    at a soil depth of 40 cm iii) in the beginning of the growing season, the  soil moisture content is    greater than 30 % at a soil depth of 60 cm, in beech and mixed beech-yew  stands, is 10-15 % in    the Q. pubescens  stands and it's more than 30 % at a soil depth of 60 cm in Q. dalechampii    stands.

scholarly journals Mapping barrier island soil moisture using a radiative transfer model of hyperspectral imagery from an unmanned aerial system

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rehman S. Eon ◽  
Charles M. Bachmann
Keyword(s):  
Soil Moisture ◽  
Radiative Transfer ◽  
Moisture Content ◽  
Layer Thickness ◽  
Soil Moisture Content ◽  
Hyperspectral Imagery ◽  
Barrier Island ◽  
Water Layer ◽  
Radiative Transfer Model ◽  
Transfer Model

AbstractThe advent of remote sensing from unmanned aerial systems (UAS) has opened the door to more affordable and effective methods of imaging and mapping of surface geophysical properties with many important applications in areas such as coastal zone management, ecology, agriculture, and defense. We describe a study to validate and improve soil moisture content retrieval and mapping from hyperspectral imagery collected by a UAS system. Our approach uses a recently developed model known as the multilayer radiative transfer model of soil reflectance (MARMIT). MARMIT partitions contributions due to water and the sediment surface into equivalent but separate layers and describes these layers using an equivalent slab model formalism. The model water layer thickness along with the fraction of wet surface become parameters that must be optimized in a calibration step, with extinction due to water absorption being applied in the model based on equivalent water layer thickness, while transmission and reflection coefficients follow the Fresnel formalism. In this work, we evaluate the model in both field settings, using UAS hyperspectral imagery, and laboratory settings, using hyperspectral spectra obtained with a goniometer. Sediment samples obtained from four different field sites representing disparate environmental settings comprised the laboratory analysis while field validation used hyperspectral UAS imagery and coordinated ground truth obtained on a barrier island shore during field campaigns in 2018 and 2019. Analysis of the most significant wavelengths for retrieval indicate a number of different wavelengths in the short-wave infra-red (SWIR) that provide accurate fits to measured soil moisture content in the laboratory with normalized root mean square error (NRMSE)< 0.145, while independent evaluation from sequestered test data from the hyperspectral UAS imagery obtained during the field campaign obtained an average NRMSE = 0.169 and median NRMSE = 0.152 in a bootstrap analysis.

Sign in / Sign up

Export Citation Format

Share Document