Coupled stochastic dynamics of water table and soil moisture in bare soil conditions

The performance of the soil water balance module (SWBM) in the models of DSSAT v3.5 was evaluated against soil moisture data measured in bare soil and dry bean plots, in Paraná, southern Brazil. Under bare soil, the SWBM showed a low performance to simulate soil moisture profiles due to inadequacies of the method used to calculate unsaturated soil water flux. Improved estimates were achieved by modifying the SWBM with the use of Darcy's equation to simulate soil water flux as a function of soil water potential gradient between consecutive soil layers. When used to simulate water balance for the bean crop, the modified SWBM improved soil moisture estimation but underpredicted crop yield. Root water uptake data indicated that assumptions on the original method limited plant water extraction for the soil in the study area. This was corrected by replacing empirical coefficients with measured values of soil hydraulic conductivity at different depths.

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Hydrologic Response of Meadow Restoration the First Year Following Removal of Encroached Conifers

Water ◽

10.3390/w11030428 ◽

2019 ◽

Vol 11 (3) ◽

pp. 428 ◽

Cited By ~ 2

Author(s):

Christopher Surfleet ◽

Thomas Sanford ◽

Gregory VanOosbree ◽

John Jasbinsek

Keyword(s):

Soil Moisture ◽

Water Table ◽

Growing Season ◽

Bare Soil ◽

Subsurface Water ◽

First Year ◽

Hydrologic Response ◽

Before And After ◽

Hydrologic Change ◽

Montane Meadow

This study examines the hydrologic response of a montane meadow the first winter following restoration by removal of encroached conifers. Hydrologic change was evaluated through statistical comparison of soil moisture and water table depths between the restored meadow, Marian Meadow, and a Control Meadow before and after restoration. Meadow water budgets and durations of water table depths during the growing season were evaluated. Electrical resistivity tomography profiles were collected to improve the spatial interpretation of subsurface water beyond well measurements. The first year following restoration Marian Meadow had a statistically significant increase in volumetric soil moisture content of 4% with depth to the water table decreasing on average by 0.15 m. The water budget for the meadows demonstrated that the hydrologic change following removal of encroached conifers was primarily due to a reduction of vegetation interception capture. Soil evapotranspiration rates in both the Control and Marian Meadows were relatively stable ranging from 268–288 mm/yr with the exception of the year following conifer removal in Marian Meadow with 318 mm/yr. The increase in soil evapotranspiration in the first post restoration year is attributed to loss of vegetation cover and higher proportions of bare soil created from the harvest operations. The duration of post-restoration water table depths during the growing season at Marian Meadow were less than or equal to 0.7 m and 0.3 m for 85 days and 50 days, respectively, indicating hydrologic conditions conducive to meadow vegetation.

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Seasonal Changes in Soil and Air Temperature at Three Locations in Puerto Rico, 1963-67

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v56i3.10837 ◽

1969 ◽

Vol 56 (3) ◽

pp. 307-317 ◽

Cited By ~ 1

Author(s):

M. A. Lugo-López ◽

Modesto Capiel

Keyword(s):

Soil Moisture ◽

Soil Temperature ◽

Air Temperature ◽

Soil Cover ◽

Bare Soil ◽

Soil Conditions ◽

Adequate Explanation ◽

The North ◽

Air Temperatures ◽

Soil Temperatures

Soil temperature data at Río Piedras in the north, Lajas in the southwest, and Fortuna in the south, are given in this paper for the 5-year period 1963- 67. Seasonal variations in soil and air temperatures follow distinct patterns somewhat, depending on the nature of the soil cover and rainfall. Mean maximum and minimum temperatures at the 2-inch depth, respectively, are: Río Piedras, 96.2° F. and 79.6° F.; Lajas, 102.1° F. and 69.0° F.; and Fortuna, 93.2° F. and 79.1° F. The corresponding soil temperatures at the 8-inch depth, respectively, are: Río Piedras, 80.5° F. and 77.4° F.; Lajas, 83.4° F. and 77.8° F.; and Fortuna, 85.7° F. and 82.7° F. The differences and trends of soil temperature at 2-inch and 8-inch depths can find adequate explanation when soil moisture and soil cover are considered. However, the differences between maximum and minimum soil temperatures at 8 inches of depth are roughly one fifth of the corresponding ones at the 2-inch depth. The maximum and minimum air temperature at Lajas, Fortuna and Río Piedras are much more similar to each other than the corresponding soil temperature, especially at the 2-inch depth. This is mainly because air temperature is rather measured on a macro and integrating scale while soil temperature measurements exhibit localized effects of soil cover and soil moisture. It was found that highly significant 2-inch soil-air temperature relationships are evident under bare soil conditions. The same relationships were not significant under sod cover at Fortuna.

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ESTIMATING UNSATURATED-ZONE HYDROLOGIC PARAMETERS USING SOIL MOISTURE, WATER TABLE, AND PRECIPITATION DATA

10.1130/abs/2018am-321377 ◽

2018 ◽

Author(s):

Megan R.M. Brown ◽

◽

Shemin Ge

Keyword(s):

Soil Moisture ◽

Water Table ◽

Unsaturated Zone ◽

Precipitation Data

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Evaluating Landscape Attractiveness with Geospatial Data, a Case Study in Flanders, Belgium

Land ◽

10.3390/land10070703 ◽

2021 ◽

Vol 10 (7) ◽

pp. 703

Author(s):

Astrid Vannoppen ◽

Jeroen Degerickx ◽

Anne Gobin

Keyword(s):

Ecosystem Services ◽

Urban Areas ◽

Policy Development ◽

Bare Soil ◽

Geospatial Data ◽

Soil Conditions ◽

Landscape Indicators ◽

Landscape Characteristics ◽

Landscape Quality

Attractive landscapes are diverse and resilient landscapes that provide a multitude of essential ecosystem services. The development of landscape policy to protect and improve landscape attractiveness, thereby ensuring the provision of ecosystem services, is ideally adapted to region specific landscape characteristics. In addition, trends in landscape attractiveness may be linked to certain policies, or the absence of policies over time. A spatial and temporal evaluation of landscape attractiveness is thus desirable for landscape policy development. In this paper, landscape attractiveness was spatially evaluated for Flanders (Belgium) using landscape indicators derived from geospatial data as a case study. Large local differences in landscape quality in (i) rural versus urban areas and (ii) between the seven agricultural regions in Flanders were found. This observed spatial variability in landscape attractiveness demonstrated that a localized approach, considering the geophysical characteristics of each individual region, would be required in the development of landscape policy to improve landscape quality in Flanders. Some trends in landscape attractiveness were related to agriculture in Flanders, e.g., a slight decrease in total agricultural area, decrease in dominance of grassland, maize and cereals, a decrease in crop diversity, sharp increase in the adoption of agri-environmental agreements (AEA) and a decrease in bare soil conditions in winter. The observed trends and spatial variation in landscape attractiveness can be used as a tool to support policy analysis, assess the potential effects of future policy plans, identify policy gaps and evaluate past landscape policy.

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Sensitivity Analysis of Bistatic Scattering for Soil Moisture Retrieval

Remote Sensing ◽

10.3390/rs13020188 ◽

2021 ◽

Vol 13 (2) ◽

pp. 188

Author(s):

Tingting Li ◽

Irena Hajnsek ◽

Kun-Shan Chen

Keyword(s):

Sensitivity Analysis ◽

Soil Moisture ◽

Quality Index ◽

High Sensitivity ◽

Bare Soil ◽

Sensitivity Index ◽

Scattering Coefficients ◽

Observation Systems ◽

Bistatic Scattering ◽

Scattering Response

Soil moisture is one of the vital environmental variables in the land–atmosphere cycle. A study of the sensitivity analysis of bistatic scattering coefficients from bare soil at the Ku-band is presented, with the aim of deepening our understanding of the bistatic scattering features and exploring its potential in soil moisture retrieval. First, a well-established advanced integral method was adopted for simulating the bistatic scattering response of bare soil. Secondly, a sensitivity index and a normalized weight quality index were proposed to evaluate the effect of soil moisture on the bistatic scattering coefficient in terms of polarization and angular diversity, and the combinations thereof. The results of single-polarized VV data show that the regions with the maximum sensitivity and high quality index, simultaneously, to soil moisture are in the forward off-specular direction. However, due to the effect of surface roughness and surface autocorrelation function (ACF), the single-polarized data have some limitations for soil moisture inversion. By contrast, the results of two different polarization combinations, as well as a dual-angular simulation of one transmitter and two receivers, show significant estimation benefits. It can be seen that they all provide better ACF suppression capabilities, larger high-sensitivity area, and higher quality indices compared to single-polarized estimation. In addition, dual polarization or dual angular combined measurement provides the possibility of retrieving soil moisture in backward regions. These results are expected to contribute to the design of future bistatic observation systems.

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Root Response to Soil Water Status via Interaction of Crop Genotype and Environment

Agronomy ◽

10.3390/agronomy11040708 ◽

2021 ◽

Vol 11 (4) ◽

pp. 708

Author(s):

Phanthasin Khanthavong ◽

Shin Yabuta ◽

Hidetoshi Asai ◽

Md. Amzad Hossain ◽

Isao Akagi ◽

...

Keyword(s):

Soil Moisture ◽

Soil Water ◽

Root Distribution ◽

Water Status ◽

Soil Layer ◽

Shoot Biomass ◽

Soil Conditions ◽

Crop Adaptation ◽

Soil Moisture Status ◽

Root Distributions

Flooding and drought are major causes of reductions in crop productivity. Root distribution indicates crop adaptation to water stress. Therefore, we aimed to identify crop roots response based on root distribution under various soil conditions. The root distribution of four crops—maize, millet, sorghum, and rice—was evaluated under continuous soil waterlogging (CSW), moderate soil moisture (MSM), and gradual soil drying (GSD) conditions. Roots extended largely to the shallow soil layer in CSW and grew longer to the deeper soil layer in GSD in maize and sorghum. GSD tended to promote the root and shoot biomass across soil moisture status regardless of the crop species. The change of specific root density in rice and millet was small compared with maize and sorghum between different soil moisture statuses. Crop response in shoot and root biomass to various soil moisture status was highest in maize and lowest in rice among the tested crops as per the regression coefficient. Thus, we describe different root distributions associated with crop plasticity, which signify root spread changes, depending on soil water conditions in different crop genotypes as well as root distributions that vary depending on crop adaptation from anaerobic to aerobic conditions.

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Impacts of soil moisture level and organic matter content on growth of two Juncus species and Poa pratensis grown under acid soil conditions

Weed Research ◽

10.1111/wre.12387 ◽

2019 ◽

Vol 59 (6) ◽

pp. 490-500

Author(s):

W Kaczmarek‐Derda ◽

M Helgheim ◽

J Netland ◽

H Riley ◽

K Wærnhus ◽

...

Keyword(s):

Organic Matter ◽

Soil Moisture ◽

Poa Pratensis ◽

Acid Soil ◽

Organic Matter Content ◽

Matter Content ◽

Moisture Level ◽

Soil Conditions ◽

Soil Moisture Level

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White Root Rot of Raspberries

Australian Journal of Biological Sciences ◽

10.1071/bi9510211 ◽

1951 ◽

Vol 4 (3) ◽

pp. 211

Author(s):

GC Wade

Keyword(s):

Soil Moisture ◽

Root Rot ◽

Soil Moisture Content ◽

Soil Conditions ◽

Causal Organism ◽

White Root Rot ◽

High Soil Moisture ◽

High Soil ◽

Soil Temperatures ◽

Dry Soil

The disease known as white root rot affects raspberries, and to a less extent loganberries, in Victoria. The causal organism is a white, sterile fungus that has not been identified. The disease is favoured by dry soil conditions and high soil temperatures. It spreads externally to the host by means of undifferentiated rhizomorphs; and requires a food base for the establishment of infection. The spread of rhizomorphs through the soil is hindered by high soil moisture content and consequent poor aeration of the soil.

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Shallow groundwater effect on land surface temperature and surface energy balance under bare soil conditions: modeling and description

Hydrology and Earth System Sciences ◽

10.5194/hess-16-1817-2012 ◽

2012 ◽

Vol 16 (7) ◽

pp. 1817-1831 ◽

Cited By ~ 16

Author(s):

F. Alkhaier ◽

G. N. Flerchinger ◽

Z. Su

Keyword(s):

Energy Balance ◽

Surface Temperature ◽

Land Surface ◽

Shallow Groundwater ◽

Bare Soil ◽

Heat Fluxes ◽

Shortwave Radiation ◽

Soil Conditions ◽

Potential Evaporation ◽

Available Energy

Abstract. Understanding when and how groundwater affects surface temperature and energy fluxes is significant for utilizing remote sensing in groundwater studies and for integrating aquifers within land surface models. To investigate the shallow groundwater effect under bare soil conditions, we numerically exposed two soil profiles to identical metrological forcing. One of the profiles had shallow groundwater. The different responses that the two profiles manifested were inspected regarding soil moisture, temperature and energy balance at the land surface. The findings showed that the two profiles differed in three aspects: the absorbed and emitted amounts of energy, the portioning out of the available energy and the heat fluency in the soil. We concluded that due to their lower albedo, shallow groundwater areas reflect less shortwave radiation and consequently get a higher magnitude of net radiation. When potential evaporation demand is sufficiently high, a large portion of the energy received by these areas is consumed for evaporation. This increases the latent heat flux and reduces the energy that could have heated the soil. Consequently, lower magnitudes of both sensible and ground heat fluxes are caused to occur. The higher soil thermal conductivity in shallow groundwater areas facilitates heat transfer between the top soil and the subsurface, i.e. soil subsurface is more thermally connected to the atmosphere. For the reliability of remote sensors in detecting shallow groundwater effect, it was concluded that this effect can be sufficiently clear to be detected if at least one of the following conditions occurs: high potential evaporation and high contrast between day and night temperatures. Under these conditions, most day and night hours are suitable for shallow groundwater depth detection.

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