An Experimental Study of the Zhao He Grassland Soil Wind Erosion Characteristics on the Northern Foothills of Yin Shan Mountain

The soil erosion test was carried out for the Zhao He grassland on the northern foothills of Yin Shan Mountain by the use of a portable wind erosion tunnel developed by Inner Mongolia Agricultural University, the variation low of soil wind erosion rate with the different wind speed and different arrangement in pairs of different soil moisture content and different vegetation coverage was obtained and the data analysis indicates that the anti-wind erosion characteristics of ground surface is most satisfactory when the vegetation coverage is 40%, soil moisture content 9.3% and the height of vegetation 50cm. The result of this study may provide a certain reference date for the application of prevention and control technology of soil wind erosion and be of vital significance to the implementation of sustainable development of livestock husbandry.

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Soil Moisture Impacts Linear and Nonlinear Erodibility Parameters from Jet Erosion Tests

Transactions of the ASABE ◽

10.13031/trans.13835 ◽

2020 ◽

Vol 63 (4) ◽

pp. 1123-1131

Author(s):

Anish Khanal ◽

Garey A. Fox ◽

Lucie Guertault

Keyword(s):

Shear Stress ◽

Soil Moisture ◽

Moisture Content ◽

Soil Moisture Content ◽

Critical Shear Stress ◽

Loam Soil ◽

Initial Resistance ◽

Erosion Test ◽

Linear And Nonlinear

HighlightsThe jet erosion test (JET) remains the most commonly used instrument for measuring in situ erodibility.This research investigated the impact of soil moisture content below saturation on erodibility parameters.Erodibility parameters were derived for both linear and nonlinear detachment models.Higher soil moisture increased initial resistance to erosion but also increased erosion rate.Abstract. The jet erosion test (JET) is a commonly employed technique to measure the erodibility of soils in situ by estimating the parameters of linear and nonlinear cohesive sediment detachment models. However, additional research is needed to understand the effect of soil moisture, a critical in situ test condition, on the derived erodibility parameters. This study compared the erodibility parameters, i.e., critical shear stress (tc) and the erodibility coefficient (kd) for the linear excess shear stress equation and two parameters (b0 and b1) for a nonlinear detachment model, from laboratory JETs across two soil types with contrasting texture and moisture contents. The general pattern was that higher soil moisture content increased the soil’s initial resistance to erosion (i.e., higher tc and b1), but once erosion was initiated the rate of erosion was greater (i.e., higher kd and b0). The magnitude of the changes in the erodibility parameters across the three soil moisture profiles investigated in this research were statistically significant, with kd and b0 varying by as much as a factor of 3. This research also confirmed the greater impact of soil moisture content on kd and b0 as compared to tc and b1. For the range of shear stress applied during these JETs, a linear detachment model was more appropriate for the sandy loam soil but less so for the more cohesive clay loam soil, but results were limited to a narrow range in applied shear stress. The results further support existing research conclusions that in situ erodibility measurements obtained under one set of soil moisture conditions may need to be adjusted to better predict soil detachment during storm events. Keywords: Cohesive soil, Critical shear stress, Detachment model, Erodibility, Jet erosion test, Shear stress, Soil moisture.

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Can Neural Networks Forecast Open Field Burning of Crop Residue in Regions with Anthropogenic Management and Control? A Case Study in Northeastern China

Remote Sensing ◽

10.3390/rs13193988 ◽

2021 ◽

Vol 13 (19) ◽

pp. 3988

Author(s):

Bing Bai ◽

Hongmei Zhao ◽

Sumei Zhang ◽

Xuelei Zhang ◽

Yabin Du

Keyword(s):

Neural Network ◽

Soil Moisture ◽

Moisture Content ◽

Crop Residue ◽

Soil Moisture Content ◽

Northeastern China ◽

Forecasting Accuracy ◽

Open Burning ◽

Natural Factors ◽

And Control

Open burning is often used to remove crop residue during the harvest season. Despite a series of regulations by the Chinese government, the open burning of crop residue still frequently occurs in China, and the monitoring and forecasting crop fires have become a topic of active research. In this paper, crop fires in Northeastern China were forecasted using an artificial neural network (ANN) based on moderate-resolution imaging spectroradiometer (MODIS) satellite fire data from 2013–2020. Both natural factors (meteorological, soil moisture content, harvest date) and anthropogenic factors were considered. The model’s forecasting accuracy under natural factors reached 77.01% during 2013–2017. When considering the influence of anthropogenic management and control policies, such as the straw open burning prohibition areas in Jilin Province, the accuracy of the forecast results for 2020 was reduced to 60%. Although the forecasting accuracy was lower than for natural factors, the relative error between the observed fire points and the back propagation neural network (BPNN) forecasting results was acceptable. In terms of influencing factors, air pressure, the change in soil moisture content in a 24h period and the daily soil moisture content were significantly correlated with open burning. The results of this study improve our ability to forecast agricultural fires and provide a scientific framework for regional prevention and control of crop residue burning.

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Prediction of Ground Surface Temperature and Soil Moisture Content by the Force-Restore Method

Water Resources Research ◽

10.1029/95wr01650 ◽

1995 ◽

Vol 31 (10) ◽

pp. 2531-2539 ◽

Cited By ~ 83

Author(s):

Zhenglin Hu ◽

Shafiqul Islam

Keyword(s):

Soil Moisture ◽

Moisture Content ◽

Surface Temperature ◽

Soil Moisture Content ◽

Ground Surface ◽

Ground Surface Temperature

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Grasslands feeling the heat: The effects of elevated temperatures on a subtropical grassland

Bothalia ◽

10.4102/abc.v46i2.2122 ◽

2016 ◽

Vol 46 (2) ◽

Cited By ~ 5

Author(s):

Rowan D. Buhrmann ◽

Syd Ramdhani ◽

Norman W. Pammenter ◽

Sershen Naidoo

Keyword(s):

Soil Moisture ◽

Moisture Content ◽

Biomass Production ◽

Soil Moisture Content ◽

Elevated Temperatures ◽

Plant Density ◽

Average Maximum ◽

Grassland Type ◽

Soil Temperatures ◽

And Control

Background: Tropical and subtropical Africa is predicted to experience a rise in temperature. The effects of rising temperatures on temperate grasslands have been studied using open-top chambers (OTCs) but reports for tropical/subtropical grasslands are scarce. This study used OTCs to investigate the effects of elevated temperatures on a threatened subtropical grassland type, namely KwaZulu-Natal Sandstone Sourveld (KZNSS).Objectives: To assess the effects of OTCs on selected abiotic parameters and plant productivity within KZNSS.Methods: Five OTC and control plots were randomly distributed at the same altitude within a patch of KZNSS. Air and soil temperature, relative humidity (RH), soil moisture content and light intensity were monitored in all plots in spring, summer, autumn and winter. Biomass production and plant density were measured in each season, for each life form (graminoid, forb and shrub), separately and combined.Results: The OTCs resulted in a rise in average, maximum and minimum day and night, air and soil temperatures. This increase, the degree of which differed across seasons, was accompanied by a decline in RH and soil moisture content. Elevated temperatures led to a significant increase in combined, graminoid and shrub above-ground productivity (AGP) and a decrease in forb density, but in certain seasons only. Below-ground biomass production was unaffected by elevated temperatures.Conclusions: OTCs can simulate realistic increases of air temperature in subtropical grasslands. Graminoids and shrubs appear to benefit from elevated temperatures whilst forbs decrease in abundance, possibly through competition and/or direct physiological effects.

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Influence of slope direction on the permafrost degradation: a case study in Qinghai-Tibetan Plateau

10.22541/au.162241121.18521624/v1 ◽

2021 ◽

Author(s):

Xingwen Fan ◽

Zhanju Lin ◽

fujiun niu ◽

Zeyong Gao ◽

Jing Luo ◽

...

Keyword(s):

Soil Moisture ◽

Tibetan Plateau ◽

Moisture Content ◽

Soil Moisture Content ◽

Ground Surface ◽

Thermal Conditions ◽

Permafrost Region ◽

Permafrost Degradation ◽

Near Surface ◽

Slope Direction

Slope direction affects permafrost degradation because of its influence on the surface energy balance. The ground thermal difference between slopes of differing aspect is known, however there are few detailed reports on differences in soil temperature, humidity, and radiation from slopes in permafrost areas that caused permafrost degradation. In this study variations in air and ground thermal regime were compared at two sloping sites with opposing aspect in a permafrost region of the Qinghai-Tibetan Plateau (QTP). The results indicate that air temperatures (Ta) were similar at both sites in September 2016-19. However, ground temperatures, including the ground surface temperature (Ts), the temperature near the permafrost surface (Tps), and the permafrost temperature at 5.0 m depth (Tg), and soil moisture content within the active layer differed greatly between sites. The mean annual Ts, Tps, and Tg over three years (2016-19) were 1.3-1.4 ℃ higher at the sunny slope than at the shady slope. The near-surface soil moisture content during the thawing season was 10-13% lower at the sunny slope (~22-27%) than the shady slope (~35-38%), and was significantly and negatively correlated with ground temperature. Shortwave downward radiation (DR) at the sunny slope was higher than at the shady slope. However, net radiation (Rn) was lower at the sunny slope due to the greater surface albedo at the site. The results highlight a complex spatial pattern of ground thermal conditions in mountainous permafrost regions, help define the climate-permafrost relation in the region, and for understanding permafrost degradation on a local scale.

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Effects of straw mulching on water consumption characteristics and yield of different types of summer maize plants

Plant Soil and Environment ◽

10.17221/404/2011-pse ◽

2012 ◽

Vol 58 (No. 4) ◽

pp. 161-166 ◽

Cited By ~ 18

Author(s):

J.Y. Shen ◽

D.D. Zhao ◽

H.F. Han ◽

X.B. Zhou ◽

Q.Q. Li

Keyword(s):

Soil Moisture ◽

Moisture Content ◽

Grain Yield ◽

Field Experiments ◽

Soil Moisture Content ◽

Ground Surface ◽

Northern China ◽

Compact Type ◽

Summer Maize ◽

Straw Mulching

To develop rainfed agriculture in northern China, we conducted field experiments with three straw mulching rates (0, 6, and 12 t/ha) on two plant types (a compact type, Chaoshi1, and a flat type, Danyu86) during the summer maize-growing season in 2009 and 2010 to study soil moisture content, evapotranspiration, grain yield, and water-use efficiency (WUE). The results indicated that straw mulching could significantly (LSD, P < 0.05) improve soil moisture content at a depth of 20–80 cm below the ground surface during the anthesis-silking stage; however, at maturity, straw mulching decreased the soil moisture content at a depth of 0–60 cm below the ground surface. In 2009, straw mulching at the rate of 12 t/ha significantly (LSD, P < 0.05) increased the evapotranspiration in Chaoshi1 and Danyu86. In 2010, straw mulching at the rate of 6 t/ha significantly (LSD,<br />P < 0.05) increased evapotranspiration in Danyu86 alone. The grain yields of Danyu86 in 2009 and Chaoshi1 in 2010 were significantly (LSD, P < 0.05) higher with straw mulching at the rate of 12 t/ha than on the application of other treatments. Irrespective of whether precipitation was concentrated during the beginning or the latter half of the summer maize growing stage, straw mulching increased the WUE of Chaoshi1, but not of Danyu86. These results indicated that under rainfed conditions in northern China, straw mulching could increase the grain yield and WUE of compact-type maize.  

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Three in one: GPS-IR measurements of ground surface elevation changes, soil moisture, and snow depth at a permafrost site in the northeastern Qinghai–Tibet Plateau

The Cryosphere ◽

10.5194/tc-15-3021-2021 ◽

2021 ◽

Vol 15 (6) ◽

pp. 3021-3033

Author(s):

Jiahua Zhang ◽

Lin Liu ◽

Lei Su ◽

Tao Che

Keyword(s):

Soil Moisture ◽

Moisture Content ◽

Active Layer ◽

Snow Depth ◽

Soil Moisture Content ◽

Ground Surface ◽

Surface Elevation ◽

Tibet Plateau ◽

Elevation Changes ◽

Qinghai Tibet Plateau

Abstract. Ground surface elevation changes, soil moisture, and snow depth are all essential variables for studying the dynamics of the active layer and permafrost. GPS interferometric reflectometry (GPS-IR) has been used to measure surface elevation changes and snow depth in permafrost areas. However, its applicability to estimating soil moisture in permafrost regions has not been assessed. Moreover, these variables were usually measured separately at different sites. Integrating their estimates at one site facilitates the comprehensive utilization of GPS-IR in permafrost studies. In this study, we run simulations to elucidate that the commonly used GPS-IR algorithm for estimating soil moisture content cannot be directly used in permafrost areas, because it does not consider the bias introduced by the seasonal surface elevation changes due to active layer thawing. We propose a solution to improve this default method by introducing modeled surface elevation changes. We validate this modified method using the GPS data and in situ observations at a permafrost site in the northeastern Qinghai–Tibet Plateau (QTP). The root-mean-square error and correlation coefficient between the GPS-IR estimates of soil moisture content and the in situ ones improve from 1.85 % to 1.51 % and 0.71 to 0.82, respectively. We also propose a framework to integrate the GPS-IR estimates of these three variables at one site and illustrate it using the same site in the QTP as an example. This study highlights the improvement to the default algorithm, which makes the GPS-IR valid in estimating soil moisture content in permafrost areas. The three-in-one framework is able to fully utilize the GPS-IR in permafrost areas and can be extended to other sites such as those in the Arctic. This study is also the first to use GPS-IR to estimate environmental variables in the QTP, which fills a spatial gap and provides complementary measurements to ground temperature and active layer thickness.

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Three-in-one: GPS-IR measurements of ground surface elevation changes, soil moisture, and snow depth at a permafrost site in the northeastern Qinghai-Tibet Plateau

10.5194/tc-2020-236 ◽

2020 ◽

Author(s):

Jiahua Zhang ◽

Lin Liu ◽

Lei Su ◽

Tao Che

Keyword(s):

Soil Moisture ◽

Moisture Content ◽

Active Layer ◽

Snow Depth ◽

Soil Moisture Content ◽

Ground Surface ◽

Surface Elevation ◽

Tibet Plateau ◽

Elevation Changes ◽

Qinghai Tibet Plateau

Abstract. Ground surface elevation changes, soil moisture, and snow depth are all essential variables for studying the dynamics of the active layer and permafrost. GPS interferometric reflectometry (GPS-IR) has been used to measure surface elevation changes and snow depth in permafrost areas. However, its applicability to estimating soil moisture in permafrost regions has not been assessed. Moreover, these variables were usually measured separately at different sites. Integrating their estimates at one site facilitates the comprehensive utilization of GPS-IR in permafrost studies. In this study, we run simulations to elucidate that the commonly-used GPS-IR method for estimating soil moisture content cannot be directly used in permafrost areas, because it does not consider the bias introduced by the seasonal surface elevation changes due to thawing of the active layer. We propose a solution to improve this default method by introducing modeled surface elevation changes. We validate this modified method using the GPS data and in situ observations at a permafrost site in the northeastern Qinghai-Tibet Plateau (QTP). The root-mean-square error and correlation coefficient between the GPS-IR estimates of soil moisture content and the in situ ones improve from 1.85 % to 1.51 % and 0.71 to 0.82, respectively. We also implement a framework to integrate the GPS-IR estimates of these three variables at one site and illustrate it using the same site in the QTP as an example. This study highlights the improvement to the default method, which makes the GPS-IR valid in estimating soil moisture content in permafrost areas. The three-in-one framework is able to fully utilize the GPS-IR in permafrost areas and can be extended to other sites such as those in the Arctic. This study is also the first to use GPS-IR to estimate environmental variables in the QTP, which fills a spatial gap and provides complementary measurements to those of ground temperature and active layer thickness.

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