scholarly journals Temporally dependent effects of rainfall characteristics on inter- and intra-event branch-scale stemflow variability in two xerophytic shrubs

2019 ◽  
Vol 23 (10) ◽  
pp. 4077-4095 ◽  
Author(s):  
Chuan Yuan ◽  
Guangyao Gao ◽  
Bojie Fu ◽  
Daming He ◽  
Xingwu Duan ◽  
...  
Keyword(s):  
Rainfall Intensity ◽  
Root Zone ◽  
Multiple Correspondence Analysis ◽  
Influential Factors ◽  
Time Lags ◽  
Event Scale ◽  
Rainfall Characteristics ◽  
Caragana Korshinskii ◽  
Funneling Ratio ◽  
Specific Species

Abstract. Stemflow is important for recharging root-zone soil moisture in arid regions. Previous studies have generally focused on stemflow volume, efficiency and influential factors but have failed to depict stemflow processes and quantify their relations with rainfall characteristics within events, particularly for xerophytic shrubs. Here, we measured the stemflow volume, intensity, funneling ratio and time lags to rain at two dominant shrub species (Caragana korshinskii and Salix psammophila) and rainfall characteristics during 54 events at the semiarid Liudaogou catchment of the Loess Plateau, China, during the 2014–2015 rainy seasons. The funneling ratio was calculated as the ratio between stemflow and rainfall intensities at the inter- and intra-event scales. Our results indicated that the stemflow of C. korshinskii and S. psammophila, on average, started at 66.2 and 54.8 min, maximized 109.4 and 120.5 min after rain began, and ended 20.0 and 13.5 min after rain ceased. The two shrubs had shorter stemflow duration (3.8 and 3.4 h) and significantly larger stemflow intensities (517.5 and 367.3 mm h−1) than those of rain (4.7 h and 4.5 mm h−1). As branch size increased, both species shared the decreasing funneling ratios (97.7–163.7 and 44.2–212.0) and stemflow intensities (333.8–716.2 and 197.2–738.7 mm h−1). Tested by the multiple correspondence analysis and stepwise regression, rainfall amount and duration controlled stemflow volume and duration, respectively, at the event scale by linear relations (p < 0.01). Rainfall intensity and raindrop momentum controlled stemflow intensity and time lags to rain for both species within the event by linear or power relationships (p < 0.01). Rainfall intensity was the key factor affecting stemflow process of C. korshinskii, whereas raindrop momentum had the greatest influence on stemflow process of S. psammophila. Therefore, rainfall characteristics had temporally dependent influences on corresponding stemflow variables, and the influence also depended on specific species.

scholarly journals Temporal-dependent effects of rainfall characteristics on inter-/intra-event stemflow variability in two xerophytic shrubs

2019 ◽  
Author(s):  
Chuan Yuan ◽  
Guangyao Gao ◽  
Bojie Fu ◽  
Daming He ◽  
Xingwu Duan ◽  
...  
Keyword(s):  
Root Zone ◽  
Multiple Correspondence Analysis ◽  
Influential Factors ◽  
Time Lags ◽  
Event Scale ◽  
Rainfall Characteristics ◽  
Caragana Korshinskii ◽  
Linear Relationships ◽  
Rain Events ◽  
Volume Efficiency

Abstract. Stemflow is important for recharging root-zone soil moisture in arid regions. Previous studies have generally focused on stemflow volume, efficiency and influential factors but have failed to depict temporal stemflow processes and quantify their relationships with rainfall characteristics within events, particularly for xerophytic shrubs. Here, we measured the stemflow volume, intensity, duration and time lags to rain events of two xerophytic shrub species (Caragana korshinskii and Salix psammophila) and rainfall characteristics for 54 events in the Liudaogou catchment of the Loess Plateau, China, during the 2014-2015 rainy seasons. The results indicated that stemflow dynamics were well synchronized to rainfall processes. The stemflows of C. korshinskii and S. psammophila had larger average intensities (4.7 ± 1.5 and 4.8 ± 1.6 mm h−1, respectively) than that of rain at the event scale (4.5 ± 1.0 mm h−1), and the stemflows were even more intense (20.3 ± 10.4 and 16.9 ± 8.8 mm h−1, respectively) than that of rain at 10-min intervals (10.9 ± 2.1 mm h−1). The average stemflow durations of C. korshinskii and S. psammophila (3.8 ± 0.8 and 3.4 ± 0.9 h, respectively) were shorter than the rainfall duration (4.7 ± 0.8 h). Tested by a multiple correspondence analysis and stepwise regression, rainfall amount and duration controlled stemflow volume and duration, respectively, at the event scale by linear relationships (p 

The state of soil microbiotes during sunflower growing with an herbicide of imidazolinone group

Helia ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Natalia Kostyuchenko ◽  
Viktor Lyakh ◽  
Anatoliy Soroka
Keyword(s):  
Species Diversity ◽  
Rhizosphere Soil ◽  
Root Zone ◽  
General Trend ◽  
The State ◽  
Trophic Groups ◽  
Herbicide Application ◽  
Fold Reduction ◽  
Specific Species ◽  
Number Of Bacteria

Abstract The effects of various concentrations of herbicide Euro-Lightning Plus on the state of microbiota in the root zone of sunflower have been studied. Soil of plant rhizosphere and interrow soil after treatment with the herbicide at the doses of 1.2 and 2.5 l/ha were taken for the analysis at the end of sunflower growing season. Rhizosphere soil without herbicide application was used as a control. The herbicide was applied at the stage of 2–4 true leaves. The total number of bacteria in the rhizosphere of control plants was 12.82 million CFU/g of soil while in the rhizosphere and in the interrow soil after herbicide treatment with a dose of 2.5 l/ha it decreased by 1.4–1.5 times. A general trend of decline in number of the basic ecological and trophic groups of bacterial microorganisms with the increase in a dose of herbicide was established. Microbiological coefficients that reflect the functional activity of the microflora indicate changes in its biological activity under the influence of the herbicide Euro-Lightning Plus, which leads to deterioration in the agroecological state of the studied soils. It was also found that herbicide application resulted in a rearrangement of micromycete complexes in the root zone of sunflower which led to a two-fold reduction, compared to the control, of mycobiota species diversity and the formation of a specific species composition of mycocenoses. A greater genus and species diversity of fungi of the microflora in the rhizosphere of control plants, in comparison with the herbicide-treated soil, was revealed. A reduction in species diversity of the genus Penicillium from six species in the control to 1–2 species in the rhizosphere of experimental sunflower plants as well as the absence of rare saprophytic fungi species from the genera Acremonium, Verticillium, Trichoderma and Paecilomyces were noted.

scholarly journals Variability of throughfall quantity in a mixed evergreen-deciduous broadleaved forest in central China

2019 ◽  
Vol 67 (3) ◽  
pp. 225-231 ◽  
Author(s):  
Lei Su ◽  
Zongqiang Xie ◽  
Wenting Xu ◽  
Changming Zhao
Keyword(s):  
Rainfall Intensity ◽  
Forest Type ◽  
Terrestrial Ecosystem ◽  
Rainfall Amount ◽  
Central China ◽  
Rainfall Characteristics ◽  
Evergreen Broadleaved Forest ◽  
Transitional Type ◽  
The Mean ◽  
Spatio Temporal

Abstract Mixed evergreen-deciduous broadleaved forest is the transitional type of evergreen broadleaved forest and deciduous broadleaved forest, and plays a unique eco-hydrologic role in terrestrial ecosystem. We investigated the spatio-temporal patterns of throughfall volume of the forest type in Shennongjia, central China. The results indicated that throughfall represented 84.8% of gross rainfall in the forest. The mean CV (coefficient of variation) of throughfall was 27.27%. Inter-event variability in stand-scale throughfall generation can be substantially altered due to changes in rainfall characteristics, throughfall CV decreased with increasing rainfall amount and intensity, and reached a quasi-constant level when rainfall amount reached 25 mm or rainfall intensity reached 2 mm h−1. During the leafed period, the spatial pattern of throughfall was highly temporal stable, which may result in spatial heterogeneity of soil moisture.

scholarly journals Chemical Element Concentrations of Cycad Leaves: Do We Know Enough?

Horticulturae ◽  
2020 ◽  
Vol 6 (4) ◽  
pp. 85 ◽  
Author(s):  
Benjamin E. Deloso ◽  
Murukesan V. Krishnapillai ◽  
Ulysses F. Ferreras ◽  
Anders J. Lindström ◽  
Michael Calonje ◽  
...  
Keyword(s):  
Root Zone ◽  
Chemical Elements ◽  
Incident Light ◽  
Leaf Age ◽  
Influential Factors ◽  
Nutrient Concentrations ◽  
Future Research ◽  
Nitrogen And Phosphorus ◽  
Element Concentrations

The literature containing which chemical elements are found in cycad leaves was reviewed to determine the range in values of concentrations reported for essential and beneficial elements. We found 46 of the 358 described cycad species had at least one element reported to date. The only genus that was missing from the data was Microcycas. Many of the species reports contained concentrations of one to several macronutrients and no other elements. The cycad leaves contained greater nitrogen and phosphorus concentrations than the reported means for plants throughout the world. Magnesium was identified as the macronutrient that has been least studied. Only 14 of the species were represented by data from in situ locations, with most of the data obtained from managed plants in botanic gardens. Leaf element concentrations were influenced by biotic factors such as plant size, leaf age, and leaflet position on the rachis. Leaf element concentrations were influenced by environmental factors such as incident light and soil nutrient concentrations within the root zone. These influential factors were missing from many of the reports, rendering the results ambiguous and comparisons among studies difficult. Future research should include the addition of more taxa, more in situ locations, the influence of season, and the influence of herbivory to more fully understand leaf nutrition for cycads.

scholarly journals How Is the Intensity of Rainfall Events Best Characterised? A Brief Critical Review and Proposed New Rainfall Intensity Index for Application in the Study of Landsurface Processes

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 929 ◽  
Author(s):  
David Dunkerley
Keyword(s):  
Rainfall Intensity ◽  
Clock Period ◽  
Event Duration ◽  
Rainfall Events ◽  
Rainfall Characteristics ◽  
Convective Storms ◽  
Intensity Index ◽  
Rainfall Depth ◽  
Minute Interval ◽  
Event Based

In many studies of landsurface processes, the intensity of rainfall events is expressed with clock-period indexes such as I30, the wettest 30-minute interval within a rainfall event. Problematically, the value of I30 cannot be estimated for rainfall events shorter than 30 min, excluding many intense convective storms. Further, it represents a diminishing proportion of increasingly long rainfall events, declining to <2% of the duration of a 30-hour event but representing 25% of the duration of a two-hour event. Here, a new index termed EDf5 is proposed: It is the rainfall depth in the wettest 5% of the event duration. This can be derived for events of any duration. Exploratory determinations of EDf5 are presented for two Australian locations with contrasting rainfall climatologies—one arid and one wet tropical. The I30 index was similar at both sites (7.7 and 7.9 mm h−1) and was unable to differentiate between them. In contrast, EDf5 at the arid site was 7.4 mm h−1, whilst at the wet tropical site, it was 3.8 mm h−1. Thus, the EDf5 index indicated a greater concentration of rain at the arid site where convective storms occurred (i.e., the intensity sustained for 5% of event duration at that site is higher). The EDf5 index can be applied to short, intense events that can readily be included in the analysis of event-based rainfall intensity. I30 therefore appears to offer less discriminatory power and consequently may be of less value in the investigation of rainfall characteristics that drive many important landsurface processes.

scholarly journals Impact of Disdrometer Types on Rainfall Erosivity Estimation

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 963
Author(s):  
Lisbeth Lolk Johannsen ◽  
Nives Zambon ◽  
Peter Strauss ◽  
Tomas Dostal ◽  
Martin Neumann ◽  
...  
Keyword(s):  
Drop Size ◽  
First Generation ◽  
Rainfall Intensity ◽  
Measurement Instrument ◽  
Rainfall Erosivity ◽  
Data Handling ◽  
Rainfall Characteristics ◽  
Different Types ◽  
Spatial Differences ◽  
Soil Erosion By Water

Soil erosion by water is affected by the rainfall erosivity, which controls the initial detachment and mobilization of soil particles. Rainfall erosivity is expressed through the rainfall intensity (I) and the rainfall kinetic energy (KE). KE–I relationships are an important tool for rainfall erosivity estimation, when direct measurement of KE is not possible. However, the rainfall erosivity estimation varies depending on the chosen KE–I relationship, as the development of KE–I relationships is affected by the measurement method, geographical rainfall patterns and data handling. This study investigated how the development of KE–I relationships and rainfall erosivity estimation is affected by the use of different disdrometer types. Rainfall data were collected in 1-min intervals from six optical disdrometers at three measurement sites in Austria, one site in Czech Republic and one site in New Zealand. The disdrometers included two disdrometers of each of the following types: the PWS100 Present Weather Sensor from Campbell Scientific, the Laser Precipitation Monitor from Thies Clima and the first generation Parsivel from OTT Hydromet. The fit of KE–I relationships from the literature varied among disdrometers and sites. Drop size and velocity distributions and developed KE–I relationships were device-specific and showed similarities for disdrometers of the same type across measurement sites. This hindered direct comparison of results from different types of disdrometers, even when placed at the same site. Thus, to discern spatial differences in rainfall characteristics the same type of measurement instrument should be used.

scholarly journals Study on the Domestic Water Utilization in Kota Metro, Lampung Province, Indonesia: Exploring Opportunities to Apply the Circular Economic Concepts in the Domestic Water Sector

2020 ◽  
Vol 12 (21) ◽  
pp. 8956
Author(s):  
Sugiyono ◽  
Bart J. Dewancker
Keyword(s):  
Water Use ◽  
Multiple Correspondence Analysis ◽  
Multinomial Logistic Regression ◽  
Household Survey ◽  
Water Source ◽  
Influential Factors ◽  
Domestic Water ◽  
Technical Problems ◽  
Water Utilization ◽  
Water Service

Providing reliable public water service is a big challenge in Indonesia, especially for small cities, due to various constraints such as budget, regulation, and technical problems. Besides, people’s preferences play a significant role in domestic water utilization. This research particularly aims to identify factors influencing public preferences for domestic water use in Kota Metro, Lampung Province, Indonesia to find the reason why public water service is less preferable in this city. We did a household survey and performed a multinomial logistic regression and multiple correspondence analysis to investigate the preferable domestic water source and influential factors determining the choice. We found that accessibility and water quality are the two strongest motives in choosing domestic water use. Our analysis also shows that the respondent’s choice is influenced by his or her income, family size, and proximity to the pipe network. Subsequently, we synthesized our empirical findings and the existing situation of the domestic water fulfillment in Kota Metro to suggest an improvement proposal inspired by the circular economy concepts. We recommend a mixture of a pipe water service and community-based water management to improve the current domestic water fulfillment.

scholarly journals Desert shrub stemflow and its significance in soil moisture replenishment

2011 ◽  
Vol 15 (2) ◽  
pp. 561-567 ◽  
Author(s):  
X.-P. Wang ◽  
Z.-N. Wang ◽  
R. Berndtsson ◽  
Y.-F. Zhang ◽  
Y.-X. Pan
Keyword(s):  
Soil Moisture ◽  
Soil Profile ◽  
Root Zone ◽  
Sand Dunes ◽  
Aluminum Foil ◽  
Time Domain Reflectometry ◽  
Desert Ecosystem ◽  
Desert Ecosystems ◽  
Caragana Korshinskii ◽  
Moisture Variation

Abstract. Stemflow of xerophytic shrubs represents a significant component of water replenishment to the soil-root system influencing water utilization of plant roots at the stand scale, especially in water scarce desert ecosystems. In this study, stemflow of Caragana korshinskii was quantified by an aluminum foil collar collection method on re-vegetated sand dunes of the Shapotou restored desert ecosystem in northwestern China. Time domain reflectometry probes were inserted horizontally at 20 different soil profile depths under the C. korshinskii shrub to monitor soil moisture variation at hourly intervals. Results indicated that 2.2 mm precipitation was necessary for the generation of stemflow for C. korshinskii. Stemflow averaged 8% of the gross precipitation and the average funnelling ratio was as high as 90. The soil moisture in the uppermost soil profile was strongly correlated with individual rainfall and the stemflow strengthened this relationship. Therefore, it is favourable for the infiltrated water redistribution in the deeper soil profile of the root zone. Consequently, stemflow contributes significantly to a positive soil moisture balance in the root zone and the replenishment of soil moisture at deeper soil layers. This plays an important role in plant survival and the general ecology of arid desert environments.

scholarly journals Spatial Interpolation of Historical Seasonal Rainfall Indices over Peninsular Malaysia

2018 ◽  
Vol 34 ◽  
pp. 02048
Author(s):  
Zulkarnain Hassan ◽  
Ahmad Haidir ◽  
Farah Naemah Mohd Saad ◽  
Afizah Ayob ◽  
Mustaqqim Abdul Rahim ◽  
...  
Keyword(s):  
Spatial Interpolation ◽  
Rainfall Intensity ◽  
Southwest Monsoon ◽  
Peninsular Malaysia ◽  
Seasonal Rainfall ◽  
Seasonal Patterns ◽  
Northeast Monsoon ◽  
Rainfall Characteristics ◽  
Distance Weighted ◽  
Inverse Distance

The inconsistency in inter-seasonal rainfall due to climate change will cause a different pattern in the rainfall characteristics and distribution. Peninsular Malaysia is not an exception for this inconsistency, in which it is resulting extreme events such as flood and water scarcity. This study evaluates the seasonal patterns in rainfall indices such as total amount of rainfall, the frequency of wet days, rainfall intensity, extreme frequency, and extreme intensity in Peninsular Malaysia. 40 years (1975-2015) data records have been interpolated using Inverse Distance Weighted method. The results show that the formation of rainfall characteristics are significance during the Northeast monsoon (NEM), as compared to Southwest monsoon (SWM). Also, there is a high rainfall intensity and frequency related to extreme over eastern coasts of Peninsula during the NEM season.

scholarly journals Estimation of the impact of short-term fluctuations in inputs on temporally aggregated outputs of process-oriented models

2003 ◽  
Vol 5 (3) ◽  
pp. 169-180 ◽  
Author(s):  
Å. Forsman ◽  
C. Andersson ◽  
A. Grimvall ◽  
M. Hoffmann
Keyword(s):  
Root Zone ◽  
Meteorological Data ◽  
Weather Conditions ◽  
Parametric Models ◽  
Time Lags ◽  
Least Squares Regression ◽  
Arable Soils ◽  
Time Step ◽  
Process Oriented ◽  
The Impact

Process-oriented models driven by highly resolved meteorological inputs and comprising a short internal time step are sometimes used to predict substance fluxes in air, soil and water over fairly long periods of time. To ascertain whether regression-based input–output analyses in such cases can provide adequate parametric models of the impact of daily and monthly fluctuations in inputs on annual outputs, we studied the SOIL/SOILN model of vertical transport of heat, water and nitrogen through arable soils. Annual leaching of nitrate from the root zone was regarded as the response variable, and regressors were selected from among the set of all linear combinations of daily or monthly values of five different meteorological inputs. We found that, although several of the underlying processes described by the SOIL/SOILN model are non-linear, both ordinary and partial least squares regression (OLS and PLS) identified the subsets of input variables with the strongest influence on the model output, and the dominating time lags between model inputs and outputs. Furthermore, highly resolved explanatory variables were a prerequisite for good performance of linear predictors of temporally aggregated outputs and, to discern the full dynamic behaviour of the model, it was necessary to analyse the response to artificially generated daily meteorological data representing a very large number of different weather conditions. PLS had one advantage over OLS: a smooth pattern in the regression coefficients facilitated physical interpretation of the derived impulse–response weights.

Sign in / Sign up

Export Citation Format

Share Document