scholarly journals Spatio-temporal variability of erosivity in Mato Grosso, Brazil

2018 ◽  
Vol 13 (6) ◽  
pp. 1
Author(s):  
Luis Augusto Di Loreto Di Raimo ◽  
Ricardo Santos Silva Amorim ◽  
Eduardo Guimarães Couto ◽  
Rodolfo Luiz Bezerra Nóbrega ◽  
Gilmar Nunes Torres ◽  
...  
Keyword(s):  
Temporal Variability ◽  
Vegetation Change ◽  
Rain Gauge ◽  
Mean Value ◽  
Rainfall Erosivity ◽  
Spatial And Temporal Variability ◽  
Mato Grosso ◽  
North West ◽  
R Factor ◽  
The Impact

The impact of rainfall on surfaces lacking vegetal cover can dissociate soil particles, thereby initiating the erosion process. This is known as rainfall erosivity and is expressed by the R factor in the Universal Soil Loss Equation. Agricultural areas often show seasonally erosion susceptibility throughout the year due to oscillations of the soil exposure rate and the vegetation change. Considering that approximately 30 million ha of the Mato Grosso State in Brazil is used for agriculture, this study aimed to predict and map the spatial and temporal variability of its territory. We evaluated the monthly (EI30) and annual (R) erosivity for 158 rain gauge stations and spatialized the values of EI30 and R by the Kriging method. It was observed that R values ranked as very high in the north, and high and medium-high in the south of Mato Grosso state. The mean value is 8835 MJ mm ha-1 h-1 year-1, considered high. Ninety-one percent of the annual erosivity was concentrated in the period between October and April, corresponding to the rainy season. The highest R factor values were found in the macro-regions of the northwest, north, west and medium-north of Mato Grosso State.

scholarly journals Assessing the sources of uncertainty associated with the calculation of rainfall kinetic energy and the erosivity <i>R</i> factor. Application to the Upper Llobregat Basin, NE Spain

2010 ◽  
Vol 7 (3) ◽  
pp. 3453-3479
Author(s):  
G. Catari ◽  
J. Latron ◽  
F. Gallart
Keyword(s):  
Kinetic Energy ◽  
Temporal Variability ◽  
Daily Precipitation ◽  
Spatial Scales ◽  
Rain Gauge ◽  
Annual Rainfall ◽  
Rainfall Erosivity ◽  
Sources Of Uncertainty ◽  
R Factor

Abstract. The sources of uncertainty associated with the calculation of rainfall kinetic energy and rainfall erosivity were investigated when the USLE R factor was operationally calculated for a mountainous river basin (504 km2) in the Southeastern Pyrenees. Rainfall kinetic energy was first obtained at the scale of the rainfall event by means of sub-hourly precipitation tipping-bucket rain gauge records and updates of the Kinnell (1981) equation. Annual erosivity values for the nearby pluviometric stations were then derived from the linear regressions between daily rainfall erosivity and daily precipitation, obtained for two different seasons. Finally, maps for rainfall erosivity estimates were obtained from the station values with Thiessen polygons. The sources of uncertainty analysed were i) the tipping-bucket instrumental errors, ii) the efficiency of the Kinnell (1981) equation, iii) the efficiency of the regressions between daily precipitation and kinetic energy, iv) the temporal variability of annual rainfall erosivity values, and the spatial variability of v) annual rainfall erosivity values and vi) long-term R factor values. The results showed that the uncertainty associated with the calculation of rainfall kinetic energy from rainfall intensity at the event and station scales is highly relevant and must be taken into account for experimental or modelling purposes; for longer temporal scales, the relevance of this source of uncertainty remains high if there is a low variability of the types of rain. Temporal variability of precipitation at wider spatial scales is the main source of uncertainty when rainfall erosivity is to be calculated on an annual basis, whereas the uncertainty associated with the long-term R factor is rather low and less important than the uncertainty associated with the other RUSLE factors when operationally used for long-term soil erosion modelling.

scholarly journals The influence of riparian woodland on the spatial and temporal variability of stream water temperatures in an upland salmon stream

2004 ◽  
Vol 8 (3) ◽  
pp. 449-459 ◽  
Author(s):  
I. A. Malcolm ◽  
D. M. Hannah ◽  
M. J. Donaghy ◽  
C. Soulsby ◽  
A. F. Youngson
Keyword(s):  
Thermal Regime ◽  
Temporal Variability ◽  
Heat Budget ◽  
Riparian Forest ◽  
Stream Water ◽  
Spatial And Temporal Variability ◽  
Substantial Impact ◽  
Site Specific ◽  
The Impact ◽  
Riparian Woodland

Abstract. The spatio-temporal variability of stream water temperatures was investigated at six locations on the Girnock Burn (30km2 catchment), Cairngorms, Scotland over three hydrological years between 1998 and 2002. The key site-specific factors affecting the hydrology and climatology of the sampling points were investigated as a basis for physical process inference. Particular emphasis was placed on assessing the effects of riparian forest in the lower catchment versus the heather moorland riparian zones that are spatially dominant in the upper catchment. The findings were related to river heat budget studies that provided process detail. Gross changes in stream temperature were affected by the annual cycle of incoming solar radiation and seasonal changes in hydrological and climatological conditions. Inter-annual variation in these controlling variables resulted in inter-annual variability in thermal regime. However, more subtle inter-site differences reflected the impact of site-specific characteristics on various components of the river energy budget. Inter-site variability was most apparent at shorter time scales, during the summer months and for higher stream temperatures. Riparian woodland in the lower catchment had a substantial impact on thermal regime, reducing diel variability (over a period of 24 hours) and temperature extremes. Observed inter-site differences are likely to have a substantial effect on freshwater ecology in general and salmonid fish in particular. Keywords: temperature, thermal regime, forest, salmon, hydrology, Girnock Burn, Cairngorm

scholarly journals The influence of a new water infrastructure development on the relative abundance of two Australian freshwater turtle species

2018 ◽  
Vol 66 (1) ◽  
pp. 57 ◽  
Author(s):  
Natalie J. Clark ◽  
Courtenay E. Mills ◽  
Nicolette A. Osborne ◽  
Kerry M. Neil
Keyword(s):  
Relative Abundance ◽  
Temporal Variability ◽  
Monitoring Program ◽  
Freshwater Turtle ◽  
Spatial And Temporal Variability ◽  
Main Body ◽  
Water Infrastructure ◽  
Turtle Species ◽  
Australian Freshwater ◽  
The Impact

Development of water infrastructure benefits water security and agriculture but poses risks to habitat and aquatic fauna. Wyaralong Dam was constructed on Teviot Brook in 2010 to provide future urban water supplies for South East Queensland, Australia. Construction of the dam created a large impoundment area and environmental impact assessment predicted significant impacts upon resident freshwater turtle species and their habitats. Differences in habitat requirements, life-history characteristics and sensitivity to change between the Macquarie River turtle (Emydura macquarii macquarii) and the common saw-shelled turtle (Myuchelys latisternum) were expected to influence the impact of the dam on the spatial and temporal abundance of these species. The relative abundance of each species was monitored at sites located within, upstream and downstream of the impoundment across wet and dry seasons during the dam’s first five years of operation. The results of this monitoring program indicate that spatial and temporal variability in the relative abundance of E. macquarii macquarii and M. latisternum occurred during the study but not all expected impacts were realised. Contrary to expectation, the relative abundance of E. macquarii macquarii did not increase over time within, upstream or downstream of the dam. M. latisternum showed greater temporal variability at some sites; however, no clear relationship between relative abundance and operational years was observed during the monitoring program. Spatial variability in relative abundance between sites was dependent upon season, with trends generally consistent across both turtle species. Where differences between species were observed, these are suspected to have resulted from the influence of environmental conditions on species-specific movement behaviours. The monitoring program confirmed the use of the upper limits of the impoundment and the plunge pool below the dam wall by both turtle species but relative abundance within the main body of the impoundment remained low throughout monitoring. The results of the study allow for consideration of the suitability of predefined management measures and the development of recommendations for future monitoring programs prescribed for water infrastructure developments.

scholarly journals Approaches to evaluate spatial and temporal variability of deep marine sediment characteristics under the impact of dense water formation events

2020 ◽  
Author(s):  
XAVIER DURRIEU de MADRON ◽  
MARION STABHOLZ ◽  
LARS-ERIC HEIMBÜRGER-BOAVIDA ◽  
DOMINIQUE AUBERT ◽  
PHILIPPE KERHERVÉ ◽  
...  
Keyword(s):  
Spatial Variability ◽  
Temporal Variability ◽  
Small Scale ◽  
Spatial And Temporal Variability ◽  
Geochemical Composition ◽  
Dense Water ◽  
Water Formation ◽  
Dense Water Formation ◽  
Northwestern Mediterranean Sea ◽  
The Impact

Dense shelf water cascading and open-ocean convection frequently occurs in the Gulf of Lions, northwestern Mediterranean Sea. These intense dense water formation events are capable of supplying large amounts of particulate matter as well as remobilizing and dispersing local sediments and, therefore, are thought to leave an imprint on superficial deposits. Here, we compared the spatial variability of the superficial sediment composition (grain size, organic parameters, and metals) at different scales (from decimetric to kilometric) on the continental slope and rise with the temporal variability linked to the occurrence of intense dense water formation events. The spatial and temporal variability of the geochemical composition of deep sediments was assessed using multivariate and geostatistical analysis. The results indicate that, on the outer reach of the Cap de Creus Canyon, where both processes interact, no clear relation was found between the temporal variability of the superficial sediment and the deep-water formation events, and that the small-scale spatial variability of the sediment is masking the temporal variability. Measurements across the southern slope indicate the presence of a somehow distinct geochemical signature that likely results from the influence of recurrent intense, dense water formation events as well as an unabating bottom trawling activity.

scholarly journals Spatial and temporal variability of water-filled crevasse hydrologic states along the shear margins of Jakobshavn Isbrae, Greenland

2017 ◽  
Author(s):  
Casey A. Joseph ◽  
Derrick J. Lampkin
Keyword(s):  
Temporal Variability ◽  
Large Strain ◽  
Water Injection ◽  
Greenland Ice Sheet ◽  
Spatial And Temporal Variability ◽  
Strain Rates ◽  
Ice Streams ◽  
Lower Elevation ◽  
Melt Water ◽  
The Impact

Abstract. The impact of melt water injection into ice streams over the Greenland Ice Sheet is not well understood. Water-filled crevasses along the shear margins of Jakobshavn Isbræ are known to fill and drain, resulting in weakening of the shear margins due to reduced basal friction. Seasonal variability in the hydrologic dynamics of these features has not been quantified. In this work, we characterize the spatial and temporal variability in the hydrological state (filled or drained) of these water-filled crevasse systems. A fusion of multi-sensor optical satellite imagery was used to examine hydrologic states from 2000 to 2015. The monthly distribution of crevasse systems observed as water filled is unimodal with peak number of filled days during the month of July at 329 days, while May has the least at 15. Over the study period the occurrence of drainage within a given season increases. Inter-seasonal drain frequencies over these systems ranged from 0 to 5. The frequency of multi-drainage events are correlated with warmer seasons and large strain rates. Over the study period, summer temperatures averaged from −1 and 2 °C and tensile strain rates have increased to as high as ~ 1.2 s-1. Intermittent melt water input during hydrofracture drainage responsible for transporting surface water to the bed is largely facilitated by high local tensile stresses. Drainage due to fracture propagation may be increasingly modulated by ocean-induced calving dynamics for the lower elevation ponds. Water-filled crevasses could expand in extent and volume as temperatures increase resulting in regional amplification of ice mass flux into the ice stream system.

scholarly journals ANÁLISE COMPARATIVA DO REGIME HÍDRICO E TÉRMICO DE DOIS SÍTIOS EXPERIMENTAIS NO PAMPA

2016 ◽  
Vol 38 ◽  
pp. 209
Author(s):  
Cláudio Alberto Teichrieb ◽  
Pablo Eli Soares de Oliveira ◽  
Tamires Zimmer ◽  
Cristiano Maboni ◽  
Daniel Michelon dos Santos ◽  
...  
Keyword(s):  
Climate Change ◽  
Carbon Dioxide ◽  
Thermal Conductivity ◽  
Water Content ◽  
Temporal Variability ◽  
Spatial And Temporal Variability ◽  
Natural Field ◽  
Field Extensions ◽  
Pampa Biome ◽  
The Impact

In the last 15-20 years has greatly increased research on the problem of climate change, necessitating a demand for reliable measurements of absorption and emission of carbon dioxide, methane, as well as the impact on water resources. In the biome Pampa are the largest continuous natural field extensions, requiring a monitoring of water and temperature regime on the ground. The water content of the soil has spatial and temporal variability affecting many hydrological processes and determining this is needed since the soil store and provide the water and nutrients for the plants, thus involving relationships water-soil-plant-atmosphere. In this work, we compared the water content behavior of the soil at depths of 10, 30 and 50 cm, the temperature of the soil at depths of 5, 15 and 30 cm, heat flux in soil installed 10 cm deep and the thermal conductivity was determined in two experimental sites in the Pampa biome, for the period 01.01.2015 to 06.31.2015. It was found that there are differences between the sites in the capacity to retain moisture in the soil and in the ability to store energy in the soil for the study period.

scholarly journals Estimating Rainfall Erosivity Factor Using Future Climate Projection in the Myjava Region (Slovakia)

2021 ◽  
Vol 24 (s1) ◽  
pp. 31-36
Author(s):  
Peter Valent ◽  
Roman Výleta
Keyword(s):  
Soil Erosion ◽  
Climate Models ◽  
Regional Climate ◽  
Multiple Linear Regression Model ◽  
Rain Gauge ◽  
Rainfall Erosivity ◽  
Extreme Rainfall Events ◽  
Rainfall Events ◽  
R Factor ◽  
Geostatistical Approach

Abstract Rainfall erosivity factor (R) of the USLE model is one of the most popular indicators of areas potentially susceptible to soil erosion. Its value is influenced by the number and intensity of extreme rainfall events. Since the regional climate models expect that the intensity of heavy rainfall events will increase in the future, the currently used R-factor values are expected to change as well. This study investigates possible changes in the values of R-factor due to climate change in the Myjava region in Slovakia that is severely affected by soil erosion. Two rain gauge stations with high-resolution 1-minute data were used to build a multiple linear regression model (r 2 = 0.98) between monthly EI 30 values and other monthly rainfall characteristics derived from low-resolution daily data. The model was used to estimate at-site R-values in 13 additional rain gauge stations homogeneously dispersed over the whole region for four periods (1981–2010, 2011–2040, 2041–2070, 2071–2100). The at-site estimates were used to create R-factor maps using a geostatistical approach. The results showed that the mean R-factor values in the region might change from 429 to as much as 520 MJ.mm.ha−1.h−1.yr−1 in the second half of the 21st century representing a 20.5% increase.

scholarly journals Effect of Lockdown amid COVID-19 Pandemic on Weather Parameters of Mid Hill Region of Jammu District of J&K, UT

2020 ◽  
pp. 53-77
Author(s):  
Mahinder Singh ◽  
Vishaw Vikas ◽  
Charu Sharma ◽  
Rohit Sharma
Keyword(s):  
Climate Change ◽  
Relative Humidity ◽  
Soil Temperature ◽  
Rain Gauge ◽  
Mean Value ◽  
Night Temperature ◽  
Hill Region ◽  
Normal Mean ◽  
Weather Parameters ◽  
The Impact

Aim: A study was conducted in mid hill region of Jammu district, J&K to analyze the impact lockdown amid covid-19 pandemic on weather parameters so as to define it as a tool to mitigate the pace of climate change. Methodology: Day and night temperature readings were recorded fortnightly during 22nd March to 10th June 2020 from maximum and minimum thermometer, relative humidity from dry and wet bulb thermometers in stevenson screen, rainfall values from ordinary rain gauge,  evaporation readings from pan evaporimeter and soil temperature at different depth from soil thermometers. Results: After analyzing the data statistically using “Descriptive statistics” in MS-Excel 2010, it was observed that after the implementation of lockdown and with the beginning of unlock down the change in day temperature was -8.07% from normal mean value, night temperature was -4.44% from normal mean value, rainfall pattern was 30.00% more from normal mean value, Relative Humidity (morning) pattern was 6.94% more from normal mean value, relative humidity (evening) pattern was 20.94% more from normal mean value, evaporation pattern was 7.66% more from normal mean value. The average change in soil temperature in morning at 5 cm, 10 cm and 20 cm depth was -3.46%, -3.84% and -7.23% as compared to year 2019 (22nd March to 10th June 2019) mean value and the change in soil temperature in evening at same depths was -7.69%, -6.31% and -4.14% from year 2019 (22nd March to 10th June 2019). Conclusion: With the variable significant pattern observed in almost all parameters, it can be concluded that lockdown might be an effective tool in mitigating pace of climate change in future.

scholarly journals Crop-management factor calculation using weights of spatio-temporal distribution of rainfall erosivity

2018 ◽  
Vol 13 (No. 3) ◽  
pp. 150-160
Author(s):  
Brychta Jiří ◽  
Janeček Miloslav ◽  
Walmsley Alena
Keyword(s):  
Temporal Distribution ◽  
Geographic Location ◽  
Crop Management ◽  
Rainfall Erosivity ◽  
Spatial And Temporal Variability ◽  
R Factor ◽  
Factor Evaluation ◽  
Spatio Temporal ◽  
Gis Environment ◽  
Crop Management Factor

Inappropriate integration of USLE or RUSLE equations with GIS tools and Remote Sensing (RS) data caused many simplifications and distortions of their original principles. Many methods of C and R factor estimation were developed due to the lack of optimal data for calculations according to original methodology. This paper focuses on crop-management factor evaluation (C) weighted by fully distributed form of rainfall erosivity factor (R) distribution throughout the year. We used high resolution (1-min) data from 31 ombrographic stations (OS) in the Czech Republic (CR) for monthly R map creation. All steps of the relatively time-consuming C calculation were automated in GIS environment with an innovative procedure of R factor weight determination for each agro-technical phase by land parcel geographic location. Very high spatial and temporal variability of rainfall erosivity within each month and throughout the year can be observed from our results. This highlights the importance of C factor calculation using a correctly presented method with emphasis on the geographic location of given land parcels.

scholarly journals Comparing Rainfall Erosivity Estimation Methods Using Weather Radar Data for the State of Hesse (Germany)

Water ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1424 ◽  
Author(s):  
Jennifer Kreklow ◽  
Bastian Steinhoff-Knopp ◽  
Klaus Friedrich ◽  
Björn Tetzlaff
Keyword(s):  
Climate Change ◽  
Rain Gauge ◽  
The State ◽  
Estimation Methods ◽  
Rainfall Erosivity ◽  
Spatiotemporal Resolution ◽  
Rain Gauge Data ◽  
R Factor ◽  
Gauge Data ◽  
Erosive Rainfall

Rainfall erosivity exhibits a high spatiotemporal variability. Rain gauges are not capable of detecting small-scale erosive rainfall events comprehensively. Nonetheless, many operational instruments for assessing soil erosion risk, such as the erosion atlas used in the state of Hesse in Germany, are still based on spatially interpolated rain gauge data and regression equations derived in the 1980s to estimate rainfall erosivity. Radar-based quantitative precipitation estimates with high spatiotemporal resolution are capable of mapping erosive rainfall comprehensively. In this study, radar climatology data with a spatiotemporal resolution of 1 km2 and 5 min are used alongside rain gauge data to compare erosivity estimation methods used in erosion control practice. The aim is to assess the impacts of methodology, climate change and input data resolution, quality and spatial extent on the R-factor of the Universal Soil Loss Equation (USLE). Our results clearly show that R-factors have increased significantly due to climate change and that current R-factor maps need to be updated by using more recent and spatially distributed rainfall data. Radar climatology data show a high potential to improve rainfall erosivity estimations, but uncertainties regarding data quality and a need for further research on data correction approaches are becoming evident.

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