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The aim of this review is to present a holistic view on irrigation with respect to local environmental and social conditions. Future irrigation development is addressed with a focus on sustainable development. However, technical irrigation aspects are included and references are provided for further reading and completeness. An irrigation intervention is always a combination of feasible technical, social and environmental aspects. This review provides an overview of the various fields of expertise involved in irrigation interventions and contributes to cross-discipline discussions and understanding. The selected cases demonstrate the bias of human developments and they serve to raise awareness of the impact of human interventions. The practical examples refer mainly to the authors’ project experiences and were selected so as to support pathways for sustainable irrigation development. Placing modern irrigation in relation to sustainable development goals needs a sophisticated holistic approach.
Willibald Loiskandl; Reinhard Nolz. Requirements for Sustainable Irrigated Agriculture. Agronomy 2021, 11, 306 .
AMA StyleWillibald Loiskandl, Reinhard Nolz. Requirements for Sustainable Irrigated Agriculture. Agronomy. 2021; 11 (2):306.
Chicago/Turabian StyleWillibald Loiskandl; Reinhard Nolz. 2021. "Requirements for Sustainable Irrigated Agriculture." Agronomy 11, no. 2: 306.
Introducing a hyperbolic vortex into a showerhead is a possibility to achieve higher spray velocities for a given discharge without reducing the nozzle diameter. Due to the introduction of air bubbles into the water by the vortex, the spray is pushed from a transition (dripping faucet) regime into a jetting regime, which results in higher droplet and jet velocities using the same nozzle diameter and throughput. The same droplet and jet diameters were realized compared to a showerhead without a vortex. Assuming that the satisfaction of a shower experience is largely dependent on the droplet size and velocity, the implementation of a vortex in the showerhead could provide the same shower experience with ~14% less water consumption compared to the normal showerhead. A full optical and physical analysis was presented, and the important chemical parameters were investigated.
Maarten V. Van De Griend; Luewton L. F. Agostinho; Elmar C. Fuchs; Nigel Dyer; Willibald Loiskandl. Consequences of the Integration of a Hyperbolic Funnel into a Showerhead for Droplets, Jet Break-Up Lengths, and Physical-Chemical Parameters. Water 2019, 11, 2446 .
AMA StyleMaarten V. Van De Griend, Luewton L. F. Agostinho, Elmar C. Fuchs, Nigel Dyer, Willibald Loiskandl. Consequences of the Integration of a Hyperbolic Funnel into a Showerhead for Droplets, Jet Break-Up Lengths, and Physical-Chemical Parameters. Water. 2019; 11 (12):2446.
Chicago/Turabian StyleMaarten V. Van De Griend; Luewton L. F. Agostinho; Elmar C. Fuchs; Nigel Dyer; Willibald Loiskandl. 2019. "Consequences of the Integration of a Hyperbolic Funnel into a Showerhead for Droplets, Jet Break-Up Lengths, and Physical-Chemical Parameters." Water 11, no. 12: 2446.
Plant root systems are essential for sustainable agriculture, conveying resource-efficient genotypes and species with benefits to soil ecosystem functions. Targeted selection of species/genotypes depends on available root system information. Currently there is no standardized approach for comprehensive root system characterization, suggesting the need for data integration across methods and sources. Here, we combine field measured root descriptors from the classical Root Atlas series with traits from controlled-environment root imaging for 10 cover crop species to (i) detect descriptors scaling between distant experimental methods, (ii) provide traits for species classification, and (iii) discuss implications for cover crop ecosystem functions. Results revealed relation of single axes measures from root imaging (convex hull, primary-lateral length ratio) to Root Atlas field descriptors (depth, branching order). Using composite root variables (principal components) for branching, morphology, and assimilate investment traits, cover crops were classified into species with (i) topsoil-allocated large diameter rooting type, (ii) low-branched primary/shoot-born axes-dominated rooting type, and (iii) highly branched dense rooting type, with classification trait-dependent distinction according to depth distribution. Data integration facilitated identification of root classification variables to derive root-related cover crop distinction, indicating their agro-ecological functions.
Gernot Bodner; Willibald Loiskandl; Wilfried Hartl; Eva Erhart; Monika Sobotik. Characterization of Cover Crop Rooting Types from Integration of Rhizobox Imaging and Root Atlas Information. Plants 2019, 8, 514 .
AMA StyleGernot Bodner, Willibald Loiskandl, Wilfried Hartl, Eva Erhart, Monika Sobotik. Characterization of Cover Crop Rooting Types from Integration of Rhizobox Imaging and Root Atlas Information. Plants. 2019; 8 (11):514.
Chicago/Turabian StyleGernot Bodner; Willibald Loiskandl; Wilfried Hartl; Eva Erhart; Monika Sobotik. 2019. "Characterization of Cover Crop Rooting Types from Integration of Rhizobox Imaging and Root Atlas Information." Plants 8, no. 11: 514.
Conservation agriculture (CA) is based on three principles: minimum soil disturbance, maintaining a soil cover through mulching with crop residues or planting cover crops, and practicing crop rotations. CA is practiced in many parts of the world for its benefits to soil and ability to improve yields, among others. There is little documented information on the status of CA adoption in the Lango region in mid-Northern Uganda. This study aimed at determining the extent of CA adoption in relation to the socioeconomic status of the farming population and suggesting relevant strategies for accelerating CA uptake specific to this region. A non-discriminative snowball-sampling technique was used to gather data from 417 households spread over three districts. Semi-structured interviews were conducted using household questionnaires. Farmers’ uptake of CA was related to information gained from training and the benefits that were observed in their fields. Some farm-level constraints in the region included the diminutive ratio of shared tools and equipment; the minimum presence and involvement of extension services; and seasonal rural markets that are dominated by middlemen. The impact that was attributed to the use of CA at the household level was improved yields. The strategy that was used to spread CA information to farmers also played a key role in increasing CA uptake in the region. This information is important for increasing CA adoption in this context given the socioeconomic status of the region.
Sara Kaweesa; Saidi Mkomwa; Willibald Loiskandl. Adoption of Conservation Agriculture in Uganda: A Case Study of the Lango Subregion. Sustainability 2018, 10, 3375 .
AMA StyleSara Kaweesa, Saidi Mkomwa, Willibald Loiskandl. Adoption of Conservation Agriculture in Uganda: A Case Study of the Lango Subregion. Sustainability. 2018; 10 (10):3375.
Chicago/Turabian StyleSara Kaweesa; Saidi Mkomwa; Willibald Loiskandl. 2018. "Adoption of Conservation Agriculture in Uganda: A Case Study of the Lango Subregion." Sustainability 10, no. 10: 3375.
Knowledge on the water content of a certain soil profile and its temporal changes due to rainfall and plant water uptake is a key issue for irrigation management. In this regard, sensors can be utilized to monitor soil water content (SWC). Due to the characteristic spatial variability of SWC, a key question is whether the measurements are representative and reliable. This study focused on the assessment of SWC and its variability in a vineyard with subsurface drip irrigation. SWC was measured in profiles down to a 50 cm depth by means of multi-sensor capacitance probes. The probes were installed at six locations along vine rows. A temporal stability analysis was performed to evaluate the representativeness and reliability of each monitoring profile with regard to irrigation control. Mean SWC was within a plausible range compared to unsaturated hydraulic parameters determined in a laboratory. The measurements revealed a considerable variability, but standard deviations were comparable to values from literature. The main finding was that some monitoring profiles (probes) proved to be more suitable to monitor SWC with respect to irrigation control than the others. Considering temporal stability provided helpful insights into the spatio-temporal variability of SWC measurements. However, not all questions that are related to the concept of temporal stability could be answered based on the given dataset.
Reinhard Nolz; W. Loiskandl. Evaluating soil water content data monitored at different locations in a vineyard with regard to irrigation control. Soil and Water Research 2017, 12, 152 -160.
AMA StyleReinhard Nolz, W. Loiskandl. Evaluating soil water content data monitored at different locations in a vineyard with regard to irrigation control. Soil and Water Research. 2017; 12 (No. 3):152-160.
Chicago/Turabian StyleReinhard Nolz; W. Loiskandl. 2017. "Evaluating soil water content data monitored at different locations in a vineyard with regard to irrigation control." Soil and Water Research 12, no. No. 3: 152-160.
Open Access Agricultural Journals published by Institute of Agricultural Economics and Information
Reinhard Nolz; W. Loiskandl; G. Kammerer; M.L. Himmelbauer. Survey of soil water distribution in a vineyard and implications for subsurface drip irrigation control. Soil and Water Research 2016, 11, 250 -258.
AMA StyleReinhard Nolz, W. Loiskandl, G. Kammerer, M.L. Himmelbauer. Survey of soil water distribution in a vineyard and implications for subsurface drip irrigation control. Soil and Water Research. 2016; 11 (No. 4):250-258.
Chicago/Turabian StyleReinhard Nolz; W. Loiskandl; G. Kammerer; M.L. Himmelbauer. 2016. "Survey of soil water distribution in a vineyard and implications for subsurface drip irrigation control." Soil and Water Research 11, no. No. 4: 250-258.
Lake sediment characterization, a pre-requirement for the vulnerability assessment of lake ecosystems, demands reliable in situ methods for the characterization of the sediment layer composition. A unified characterization of lake sediments within different lake ecotopes (open water, open water patches within the reed, and the reed) is still a challenge. Each ecotope is covered by different classical scientific disciplines (hydrography and terrestrial remote sensing to soil physics) with their specific characterization methods. However, a complementary tool that bridges the gap between land- and hydrographic surveying methods is still missing. Therefore a combination of soil physical sensors (a capacitive sensor and a cone penetrometer) in a measuring system (CSPS) was introduced. CSPS is a non-acoustic device for the rapid in situ delineation of water-mud-consolidated lakebed interfaces. The system was successfully applied across the different ecotopes at the Neusiedler See, a well-mixed shallow lake rich in fine-grained sediments. The geo-referenced vertical CSPS profiles show ecotope-specific layer composition. The effect of wind induced turbidity, particle size, and electrical conductivity were analysed. The water–mud interface was precisely delineated at the open water due to a persistent high water content gradient, equivalent to a lutocline. The penetration resistance for open water showed either a shallow and highly-compacted consolidated lakebed or a consolidated lakebed with a partially compacted layer above; while in the reed the penetration resistance smoothly increased until reaching the deepest penetration depths.
I. Kogelbauer; W. Loiskandl. Characterization of sediment layer composition in a shallow lake: from open water zones to reed belt areas. Hydrology and Earth System Sciences Discussions 2014, 1 .
AMA StyleI. Kogelbauer, W. Loiskandl. Characterization of sediment layer composition in a shallow lake: from open water zones to reed belt areas. Hydrology and Earth System Sciences Discussions. 2014; ():1.
Chicago/Turabian StyleI. Kogelbauer; W. Loiskandl. 2014. "Characterization of sediment layer composition in a shallow lake: from open water zones to reed belt areas." Hydrology and Earth System Sciences Discussions , no. : 1.
Roots are essential drivers of soil structure and pore formation. This study aimed at quantifying root induced changes of the pore size distribution (PSD). The focus was on the extent of clogging vs. formation of pores during active root growth. Parameters of Kosugi’s lognormal PSD model were determined by inverse estimation in a column experiment with two cover crops (mustard, rye) and an unplanted control. Pore dynamics were described using a convection–dispersion like pore evolution model. Rooted treatments showed a wider range of pore radii with increasing volumes of large macropores >500 μm and micropores <2.5 μm, while fine macropores, mesopores and larger micropores decreased. The non-rooted control showed narrowing of the PSD and reduced porosity over all radius classes. The pore evolution model accurately described root induced changes, while structure degradation in the non-rooted control was not captured properly. Our study demonstrated significant short term root effects with heterogenization of the pore system as dominant process of root induced structure formation. Pore clogging is suggested as a partial cause for reduced pore volume. The important change in micro- and large macropores however indicates that multiple mechanic and biochemical processes are involved in root-pore interactions.
P. Scholl; D. Leitner; G. Kammerer; W. Loiskandl; H.-P. Kaul; G. Bodner. Root induced changes of effective 1D hydraulic properties in a soil column. Plant and Soil 2014, 381, 193 -213.
AMA StyleP. Scholl, D. Leitner, G. Kammerer, W. Loiskandl, H.-P. Kaul, G. Bodner. Root induced changes of effective 1D hydraulic properties in a soil column. Plant and Soil. 2014; 381 (1):193-213.
Chicago/Turabian StyleP. Scholl; D. Leitner; G. Kammerer; W. Loiskandl; H.-P. Kaul; G. Bodner. 2014. "Root induced changes of effective 1D hydraulic properties in a soil column." Plant and Soil 381, no. 1: 193-213.
For many water management issues of shallow lakes with non-consolidated sediments hydrographic surveys of the open water area and reed belt areas are required. In the frame of water management strategy for the steppe lake Neusiedler See, located between Austria and Hungary, a hydrographic survey was conducted. In the open water area (water depth ≥1 m) a sediment echosounder was used. To validate these measurements and to distinguish between water, mud, and sediment layers in the shallow lake and reed belt area additional measurements were needed. As no common standard methods are available yet, we developed a measurement system based on two commonly applied soil physical measurement techniques providing reproducible physical values: a capacitive sensor and a cone penetrometer combined with GNSS-positioning enable dynamic measurements of georeferenced vertical water-mud-bedsediments profiles. The system bases on site-specific calibrated sensors and allows instantaneous, in situ measurements. The measurements manifest a sharp water-mud interface by a sudden decline to smaller water content which is a function of the dielectric permittivity. A second decline indicates the transition to compacted mud. That is concurrently the density where the penetrometer starts registering significant penetration resistance. The penetrometer detects shallow lakebed-sediment layers. Within the lake survey this measurement system was successfully tested.
Ilse Kogelbauer; Erwin Heine; Christopher D'amboise; Christoph Müllebner; Wolfgang Sokol; Willibald Loiskandl. Adaptation of Soil Physical Measurement Techniques for the Delineation of Mud and Lakebed Sediments at Neusiedler See. Sensors 2013, 13, 17067 -17083.
AMA StyleIlse Kogelbauer, Erwin Heine, Christopher D'amboise, Christoph Müllebner, Wolfgang Sokol, Willibald Loiskandl. Adaptation of Soil Physical Measurement Techniques for the Delineation of Mud and Lakebed Sediments at Neusiedler See. Sensors. 2013; 13 (12):17067-17083.
Chicago/Turabian StyleIlse Kogelbauer; Erwin Heine; Christopher D'amboise; Christoph Müllebner; Wolfgang Sokol; Willibald Loiskandl. 2013. "Adaptation of Soil Physical Measurement Techniques for the Delineation of Mud and Lakebed Sediments at Neusiedler See." Sensors 13, no. 12: 17067-17083.
Alfred Strauss; Janez Schellander; Michael Reiterer; Richard Wagner; Willibald Loiskandl; Konrad Bergmeister. Reduktion von Pendelschwingungen im Ingenieurbau mittels Füssigkeitstilgersystemen. Bautechnik 2013, 90, 421 -432.
AMA StyleAlfred Strauss, Janez Schellander, Michael Reiterer, Richard Wagner, Willibald Loiskandl, Konrad Bergmeister. Reduktion von Pendelschwingungen im Ingenieurbau mittels Füssigkeitstilgersystemen. Bautechnik. 2013; 90 (7):421-432.
Chicago/Turabian StyleAlfred Strauss; Janez Schellander; Michael Reiterer; Richard Wagner; Willibald Loiskandl; Konrad Bergmeister. 2013. "Reduktion von Pendelschwingungen im Ingenieurbau mittels Füssigkeitstilgersystemen." Bautechnik 90, no. 7: 421-432.
Geostatistical estimation methods including ordinary kriging (OK), lognormal ordinary kriging (LOK), cokriging (COK), and indicator kriging (IK) are compared for the purposes of prediction and, in particular, uncertainty assessment of the soil texture fractions, i.e. sand, silt, and clay proportions, in an erosion experimental field in Lower Austria. The soil samples were taken on 136 sites, about 30-m apart. The validation technique was cross-validation, and the comparison criteria were the mean bias error (MBE) and root mean squared error (RMSE). Statistical analysis revealed that the sand content is positively skewed, thus persuading us to use LOK for the estimation. COK was also used due to a good negative correlation seen between the texture fractions. The autocorrelation analysis showed that the soil texture fractions in the study area are strongly to moderately correlated in space. Cross-validation indicated that COK is the most accurate method for estimating the silt and clay contents; RMSE equalling to 3.17% and 1.85%, respectively. For the sand content, IK with RMSE (12%) slightly smaller than COK (RMSE = 14%) was the best estimation method. However, COK maps presented the true variability of the soil texture fractions much better than the other approaches, i.e. they achieved the smallest smoothness. Regarding the local uncertainty, the estimation variance maps produced by OK, LOK, and COK methods similarly indicated that the lowest uncertainty occurred near the data locations, and that the highest uncertainty was seen in the areas of sparse sampling. The uncertainty, however, varied much less across the study area compared to conditional variance for IK. The IK conditional variance maps showed, in contrast, some relations to the data values. The estimation uncertainty needs to be evaluated for the incorporation into the risk analysis in the soil management.
M. Delbari; P. Afrasiab; W. Loiskandl. Geostatistical analysis of soil texture fractions on the field scale. Soil and Water Research 2011, 6, 173 -189.
AMA StyleM. Delbari, P. Afrasiab, W. Loiskandl. Geostatistical analysis of soil texture fractions on the field scale. Soil and Water Research. 2011; 6 (No. 4):173-189.
Chicago/Turabian StyleM. Delbari; P. Afrasiab; W. Loiskandl. 2011. "Geostatistical analysis of soil texture fractions on the field scale." Soil and Water Research 6, no. No. 4: 173-189.
Soil hydraulic properties are subject to temporal changes as a response to both tillage and natural impact factors. As the temporal and spatial variability might exceed cultivation-induced differences, there is a need to better differentiate between those influence factors. Thus, the objective of the present study was to assess the impact of different tillage techniques – conventional (CT), reduced (RT), and no-tillage (NT) – on the soil hydraulic properties and their temporal dynamics. On a silt loam soil, tension infiltrometer measurements were obtained frequently over two consecutive years. The data was analyzed in terms of the near-saturated hydraulic conductivity, inversely estimated parameters of the van Genuchten/Mualem (VGM) model, and the water-conducting porosity. Our results show that the near-saturated hydraulic conductivity was in the order CT > RT > NT, with larger treatment-induced differences where water flow is dominated by mesopores. The VGM model parameterαVG was in the order CT < RT < NT, with high temporal variations under CT and RT, whereas the parameter n was hardly affected. NT resulted in the greatest water-conducting pore radii, whereas no distinct differences were observed between CT and RT. The results give indirect evidence that NT leads to greater connectivity and smaller tortuosity of macropores, possibly due to a better established soil structure and biological activity. NT also resulted in a better temporal stability of both the pore network and the hydraulic properties, but showed the highest spatial variability of macropores. We suggest that the hydraulically effective pores decreased after tillage in response to rainfall during winter, and gradually increased in spring and summer induced by biological activity, root development and wetting/drying cycles. A multivariate ANOVA revealed that variations in mesopore-related quantities could be explained sufficiently by an interaction of tillage and time. By contrast, due to high spatial variability, macropore-related quantities could not be explained by those influence factors. The study reveals the importance of the temporal dynamics for both hydraulic properties and the water-conducting porosity.
Andreas Schwen; Gernot Bodner; Peter Scholl; Graeme D. Buchan; Willibald Loiskandl. Temporal dynamics of soil hydraulic properties and the water-conducting porosity under different tillage. Soil and Tillage Research 2011, 113, 89 -98.
AMA StyleAndreas Schwen, Gernot Bodner, Peter Scholl, Graeme D. Buchan, Willibald Loiskandl. Temporal dynamics of soil hydraulic properties and the water-conducting porosity under different tillage. Soil and Tillage Research. 2011; 113 (2):89-98.
Chicago/Turabian StyleAndreas Schwen; Gernot Bodner; Peter Scholl; Graeme D. Buchan; Willibald Loiskandl. 2011. "Temporal dynamics of soil hydraulic properties and the water-conducting porosity under different tillage." Soil and Tillage Research 113, no. 2: 89-98.
Soil water managementcan be defined as active involvement in controlling soil water content at an optimal state for all given purposes, including environmental needs. An optimal state is often a...
Willibald Loiskand; Gerhard Kammerer. Soil Water Management. Encyclopedia of Solid Earth Geophysics 2011, 802 -805.
AMA StyleWillibald Loiskand, Gerhard Kammerer. Soil Water Management. Encyclopedia of Solid Earth Geophysics. 2011; ():802-805.
Chicago/Turabian StyleWillibald Loiskand; Gerhard Kammerer. 2011. "Soil Water Management." Encyclopedia of Solid Earth Geophysics , no. : 802-805.
Rainwater harvesting (RWH) is practised to mitigate water shortages in both household chores and agricultural use. This paper examines the relationship between adoption of household RWH technologies in rural Uganda (dependant variable), and the influence of independent variables (household characteristics such as age or monthly cash income, household perception including attitude or risk preference, and institutional and policy-assumed variables such as household’s contact with extension workers, RWH-subsidy provision, information flow channels and local community financial sources) that potentially influence technological adoption. Logistic regression techniques were used on a random sample of 224 respondents to ascertain the influence of variables on adoption of household RWH technologies. Analyses of hypothesised relationships revealed that subsidy provision was statistically significant for adoption of RWH technologies in rural Uganda. Overall, the paper suggests the consideration of household RWH subsidies in form of hardware when promoting adoption of RWH technologies. Moreover, when subsidies in the form of RWH construction materials are provided, the chances of having a RWH system installed seem more likely than when cash is provided owing to the many options cash can be used to purchase. Furthermore, household subsidy provision will produce immediate improvement in rural water supply, fostering the probability of adoption of rainwater technologies, a choice that can be made with regard to the form or level of public subsidy received depending on institutional and policy interventions.
David Baguma; Willibald Loiskandl. Rainwater harvesting technologies and practises in rural Uganda: a case study. Mitigation and Adaptation Strategies for Global Change 2010, 15, 355 -369.
AMA StyleDavid Baguma, Willibald Loiskandl. Rainwater harvesting technologies and practises in rural Uganda: a case study. Mitigation and Adaptation Strategies for Global Change. 2010; 15 (4):355-369.
Chicago/Turabian StyleDavid Baguma; Willibald Loiskandl. 2010. "Rainwater harvesting technologies and practises in rural Uganda: a case study." Mitigation and Adaptation Strategies for Global Change 15, no. 4: 355-369.
Water management in rural domestic households plays an important role in reducing water-related health risks. This study was conducted to examine the relationships between the dependent variable (rural domestic rainwater management) and the independent predictive variables (personal characteristics, tank size, years of water harvest, rainwater harvesting associations, usage instructions including water borne health risk, and tank operation and maintenance) in Uganda. Logistic regression techniques were used on a random sample of 301 respondents to ascertain the influence of predictive variables on rural domestic rainwater management. Analyses of the hypothesised relationship revealed three statistically significant results: years of water harvest, rainwater harvesting associations and usage instructions. Overall, the findings suggest that consideration of usage instructions including waterborne health risks, years of harvest, and local water associations, will improve domestic water management, in combination with progressive measures focused on water quality and quantity. Moreover, medical expenses and time spent in hospitals or health dispensaries will be minimised and saved through utilisation of usage instructions. Experienced harvesting households, those with few years of harvest, and non participants as well in local water associations will easily enrich knowledge of how to minimise contracting water-related diseases.
David Baguma; Willibald Loiskandl; Helmut Jung. Water Management, Rainwater Harvesting and Predictive Variables in Rural Households. Water Resources Management 2010, 24, 3333 -3348.
AMA StyleDavid Baguma, Willibald Loiskandl, Helmut Jung. Water Management, Rainwater Harvesting and Predictive Variables in Rural Households. Water Resources Management. 2010; 24 (13):3333-3348.
Chicago/Turabian StyleDavid Baguma; Willibald Loiskandl; Helmut Jung. 2010. "Water Management, Rainwater Harvesting and Predictive Variables in Rural Households." Water Resources Management 24, no. 13: 3333-3348.
Soil organic carbon (SOC) affects many processes in soil. The main objective of this study was the prediction and uncertainty assessment of the spatial patterns of SOC through stochastic simulation using 2 simulation algorithms, sequential Gaussian simulation (sGs) and sequential indicator simulation (sis). The dataset consisted of 158 point measurements of surface SOC taken from an 18-ha field in Lower Austria. Conditional stochastic simulation algorithms were used to generate 100 maps of equiprobable spatial distribution for SOC. In general the simulated maps represented spatial distribution of SOC more realistically than the kriged map, i.e. overcoming the smoothing effect of kriging. Unlike sGs, sis was able to preserve the connectivity of extreme values in generated maps. The SOC simulated maps generated through sGs reproduced the sample statistics well. The reproduction of class-specific patterns of spatial continuity of SOC for the simulated model produced through sis was also reasonably good. The results highlight that when the class-specific patterns of spatial continuity of the attribute must be preserved, sis is preferred to sGs. For local uncertainty, standard deviations obtained using kriging varied much less across the study area than those obtained using simulations. This shows that the conditional standard deviations achieved through simulations depend on data values in addition to data configuration for greater reliability in reporting the estimation precision. Further, according to accuracy plots and goodness statistic, G, sis performs the modelling uncertainty better than sGs. The simulated models can provide useful information in risk assessment of SOC management in Lower Austria.
Masoomeh Delbari; Willibald Loiskandl; Peyman Afrasiab. Uncertainty assessment of soil organic carbon content spatial distribution using geostatistical stochastic simulation. Soil Research 2010, 48, 27 -35.
AMA StyleMasoomeh Delbari, Willibald Loiskandl, Peyman Afrasiab. Uncertainty assessment of soil organic carbon content spatial distribution using geostatistical stochastic simulation. Soil Research. 2010; 48 (1):27-35.
Chicago/Turabian StyleMasoomeh Delbari; Willibald Loiskandl; Peyman Afrasiab. 2010. "Uncertainty assessment of soil organic carbon content spatial distribution using geostatistical stochastic simulation." Soil Research 48, no. 1: 27-35.
Soil water content (SWC) has a vital role in a variety of hydrological processes such as infiltration, runoff and erosion. Mapping the spatial pattern of SWC is then essential for appropriate addressing of these processes. Geostatistics is often used to characterize the spatial variability of SWC. This information may be used for estimating SWC e.g., by ordinary kriging (OK) or modeling location-specific uncertainty (local uncertainty) of the estimates by indicator kriging (IK). Kriging-based algorithms however smooth out the details and are incapable of detecting multi-location uncertainty (spatial uncertainty) of SWC estimates. Sequential Gaussian simulation (sGs) can model the spatial uncertainty through generation of several equally probable stochastic realizations. In this study sGs is used to map SWC spatial distribution and to provide a quantitative measure of its spatial uncertainty in particular. The SWC measurements were performed on 157 soil samples taken from an 18 ha erosion experiment field in Lower Austria. The results show that the spatial pattern of SWC is well recognized using the sGs as the simulated models reproduce the sample statistics including histogram and semivariogram model reasonably well. The difference among realizations is used to provide a quantitative measure of spatial uncertainty of SWC estimates. Knowledge of spatial uncertainty is helpful to evaluate the delineation of vulnerable areas to erosion.
Masoomeh Delbari; Peyman Afrasiab; Willibald Loiskandl. Using sequential Gaussian simulation to assess the field-scale spatial uncertainty of soil water content. CATENA 2009, 79, 163 -169.
AMA StyleMasoomeh Delbari, Peyman Afrasiab, Willibald Loiskandl. Using sequential Gaussian simulation to assess the field-scale spatial uncertainty of soil water content. CATENA. 2009; 79 (2):163-169.
Chicago/Turabian StyleMasoomeh Delbari; Peyman Afrasiab; Willibald Loiskandl. 2009. "Using sequential Gaussian simulation to assess the field-scale spatial uncertainty of soil water content." CATENA 79, no. 2: 163-169.
Dielectric-based sensors are widely used for field monitoring of soil volumetric water content (θv), including in situ applications in ecological monitoring programs. However, sensor response depends strongly on the location-specific soil properties, which in turn affects measurement accuracy and data processing. Published general or manufacturers' calibrations often misrepresent the θv-sensor output relationship, requiring soil-specific calibration. We report on use of the CS615 Water Content Reflectometer (WCR) to monitor the soil water dynamics in a creeping flow at a landslide site (Bad Goisern, Austria), and on the soil-specific adjustment of measurement errors. Extraordinary soil conditions (high clay and water contents) caused anomalous overestimation of θv via the manufacturer's standard calibration. Further, a laboratory calibration had to be aborted due to the intractable soil material. However an in situ field calibration and an ex situ field-soil calibration successfully provided relations between θv and the probe output (multivibrator period, τ). The calibration was performed as a two-stage procedure according to the inverse regression method. Linear (LR) and multiple (MR) regression models and polynomial (P2, P3) relations were generated via regression analyses. Bias, mean squared error (MSE) and mean deviation (MD) were used to evaluate the quality of θv estimation using the inverse prediction function. LR and MR models provided better data adjustment than polynomial functions. Best results were derived from MR models including as additional variables temperature (T) and porosity (P), and subset-specific (S) to sensor position in the field (model MR TP S). Measurement error was reduced from 0.068 ± 0.122 m3 m− 3 (MSE ± σ for the standard calibration) to 0.001 ±0.002 m3 m− 3 (MSE ± σ for the MR TP S model). Restricted sample size and moisture range impaired the statistical analyses of both field soil calibrations. Deviations of sensor response specific to soil layer and sensor position were observed and statistically confirmed. However, reasonable location-specific calibration functions were obtained for both the entire water content range and the site-specific high moisture range. Our results indicate an especially anomalous, soil pH-dependent response of the WCR (which operates in the lower frequency range 15 to 45 MHz) in a smectite-dominated soil, partly consistent with the findings of Ishida and Makino (1999) for the dielectric behaviour of montmorillonite suspensions. Unfavourable soil conditions, especially high moisture levels combined with high clay contents, demonstrated the limits of WCR-application. Our findings strongly support media-specific sensor calibration over general calibrations, especially for soils with extraordinary and challenging properties.
R. Stangl; G.D. Buchan; W. Loiskandl. Field use and calibration of a TDR-based probe for monitoring water content in a high-clay landslide soil in Austria. Geoderma 2009, 150, 23 -31.
AMA StyleR. Stangl, G.D. Buchan, W. Loiskandl. Field use and calibration of a TDR-based probe for monitoring water content in a high-clay landslide soil in Austria. Geoderma. 2009; 150 (1-2):23-31.
Chicago/Turabian StyleR. Stangl; G.D. Buchan; W. Loiskandl. 2009. "Field use and calibration of a TDR-based probe for monitoring water content in a high-clay landslide soil in Austria." Geoderma 150, no. 1-2: 23-31.
Für die Universitäten stellt die Entwicklungszusammenarbeit (EZA) einen wichtigen Bereich dar. Die EZA ist eine Herausforderung als Wissenstransferquelle und in der Förderung der institutionellen Entwicklung der Partneruniversitäten. Dies gilt auch im besonderen Maß für die landeskulturelle Wasserwirtschaft, da weltweit die Forderung nach einer effizienten Wassernutzung in der Nahrungsproduktion immer eindringlicher wird. In den letzten Jahren wurde dieser Herausforderung verstärkt Rechnung getragen. Ausgewählte signifikante Beispiele sollen, stellvertretend für viele Aktivitäten, dies auch praktisch dokumentieren. Neben den technischen Aspekten werden die Voraussetzungen für erfolgreiche Partnerschaften und die sozialen und ökonomischen Rahmenbedingungen beleuchtet. Ein nicht unwesentlicher Teil ist die Behandlung von Konflikten und Fragen der Gleichberechtigung der involvierten Gruppen.
W. Loiskandl; A. Strauss-Sieberth; Ph. Floch; F. Kaštánek. Entwicklungszusammenarbeit — eine Herausforderung für die landeskulturelle Wasserwirtschaft. Österreichische Wasser- und Abfallwirtschaft 2006, 58, 105 -110.
AMA StyleW. Loiskandl, A. Strauss-Sieberth, Ph. Floch, F. Kaštánek. Entwicklungszusammenarbeit — eine Herausforderung für die landeskulturelle Wasserwirtschaft. Österreichische Wasser- und Abfallwirtschaft. 2006; 58 (7):105-110.
Chicago/Turabian StyleW. Loiskandl; A. Strauss-Sieberth; Ph. Floch; F. Kaštánek. 2006. "Entwicklungszusammenarbeit — eine Herausforderung für die landeskulturelle Wasserwirtschaft." Österreichische Wasser- und Abfallwirtschaft 58, no. 7: 105-110.