Biochar application does not improve the soil hydrological function of a sandy soil

The high profile failure of the Malahide Viaduct in Dublin, Ireland, which is a part of the EU TEN-T network of critical transport links, was caused by foundation scour. Scour is a common soil-structure interaction problem. In light of current changes in climate, increasing frequency of flooding, coupled with the increasing magnitude of these flood events, will lead to a higher risk of bridge failure. Monitoring scour is of paramount importance to ensure the continued safe operation of the aging bridge asset network. Most monitoring regimes are based on expensive underwater instrumentation that can often be subjected to damage during times of flooding, when scour risk is at its highest. This paper presents a critical review of existing scour monitoring equipments and methodologies with a particular focus on those using the dynamic response of the structure to indicate the existence and severity of the scour phenomenon affecting the structure. A sensitivity study on a recently developed monitoring method is also undertaken.

https://researchrepository.ucd.ie/bitstream/10197/6521/1/UCDLukePrendergast_ScourReview.pdf

A review of bridge scour monitoring techniques

The addition of biochar (BC) has been suggested to increase the soil fertility and crop productivity of agricultural lands. This study evaluated the effect of different levels of BC on properties of sandy desert soils and its ultimate impact on plant growth. The samples of desert sand were taken from the Kubuqi of Inner Mongolia, China and the Thar Desert, Pakistan. The sands were treated with a BC made from the fast pyrolysis of pine sawdust at 400 °C. Four BC application rates i.e. 0, 15, 22 and 45 t ha − 1 were used in this study. Effects of BC addition on the water consumption and plant growth of sorghum were monitored for eight weeks in a pot experiment. The hydraulic and chemical properties of soil were analyzed to discern the effect of BC on the fertility of sandy desert soils. The results showed that BC amendment significantly improved soil hydraulic and chemical properties. The BC applied at the rate of 22 t ha − 1 provided the best results as compared to all other treatments. Compared with the control group, the soil water-holding capacity (WHC) increased by 11% and 14%, water-retention capacity (WRC) increased by 28% and 32% and hydraulic conductivity decreased by 32% and 7% under the Kubuqi and the Thar Desert soils, respectively when BC was applied at 22 t ha − 1 . Similarly, total C increased by 11% and 7%, total K increased by 37% and 42%, total P increased by 70% and 68% and total Ca increased by 69% and 75% while soil pH significantly reduced by 0.67 and 0.79 units, in the Kubuqi and the Thar Desert soils, respectively. The sorghum dry matter yield (DMY) was also significantly improved by 18% and 22% under the Kubuqi and the Thar Desert soils, respectively. The higher sorghum DMY consequently improved water-use efficiency (WUE) by 40% and 41% under the Kubuqi and the Thar Desert soils, respectively. In contrast, the plant growth and DMY declined at higher application rate (45 t ha − 1 ) of BC. The BC made from fast pyrolysis of pine sawdust at a temperature of 400 °C showed great potential in improving the quality of sandy desert soils. Hence, it can be used for sandy desert soil management.

Effects of biochar application rate on sandy desert soil properties and sorghum growth

This study provides a model for result consistency evaluation of multi-criteria decision-making (MDM) methods and selection of the optimal one. The study presents the results of an analysis of the sensitivity of decision-making based on the rank methods: SAW, MOORA, VIKOR, COPRAS, CODAS, TOPSIS, D’IDEAL, MABAC, PROMETHEE-I,II, ORESTE-II with variations in the elements in the decision matrix within a given error (imprecision). It is suggested to use multiple simulation of the elements estimations of the decision matrix within a given error for calculating the ranks of alternatives, which allows obtaining statistical estimates of ranks. Based on the statistics of simulations, decision-making can be carried out not only on the alternatives statistics having rank I but also on the statistics of alternatives having the largest total I and II rank or I, II and III ranks. This is especially true when the difference in rank values ​​is not large and is distributed evenly among the first three ranks. The calculations results for the task of selecting the adequate location of 8 objects by 11 criteria are presented here. The main result shows that the alternatives having I, II and III ranks for some ranking methods are not distinguishable within the selected error value of the elements in the decision matrix. A quantitative analysis can only narrow the number of effective alternatives for a final decision. A statistical analysis makes the number of options estimation possible in which an alternative has a priority. Additional criteria that take into account both aggregate priorities and the availability of possible priorities for other alternatives with small variations in the decision matrix provide additional important information for the decision-maker.

/pdf/a-sensitivity-analysis-in-mcdm-problems-a-statistical-4fa7mmpo1p.pdf

A sensitivity analysis in MCDM problems: A statistical approach

Biochar has potential as a valuable tool for the agricultural industry with its unique ability to help build soil health, increase physical properties of soil,
 soil pH, organic carbon content, conserve water and mitigate drought, reduce GHG emission, conserve nutrients, decrease fertilizer requirements, sequester carbon, increase crop productivity and serve as a most preferred habitat for microbes. In this study, three perishable biomass wastes viz. Pea pod (Pisum sativum), cauliflower leaves (Brassica oleracea) and orange peel wastes (Citrus sinensis) were carbonized and characterized for differential application. The biomass was subjected to carbonization at different temperatures from 100 to 600 °C for 1 h. Biomass and biochar samples were characterized for proximate (M, VM, FC, Ash), ultimate (CHNS-O), biochemical properties (Ce, He, Li), thermo gravimetric analysis, pH, EC and bulk density. The biochars were also analyzed through SEM and FTIR for identification of pore size and functional groups. The char yield was high in cauliflower leaf (30.16 %), followed by orange peel (25.54 %) and pea pod (21.154 %) at 300 °C. The total organic carbon (11.61 %), total negative surface anions (4.25 mmol H+ eq/g C) and water holding capacity (200 %) were high in pea pod biochar. The SEM images of biochar samples showed plane cleavage surfaces with broken edges. The surface functional groups of all the three biochar samples were hydroxyl, methyl, carboxylic and alkene groups. The pea pod and cauliflower leaf biochar showed higher values of organic carbon, total surface anions, water holding capacity and mineral content and performed as best soil amendment than orange peel biochar. These biochar can be used as an effective medium for increasing soil carbon, irrigation efficiency and efficient disposal of agricultural waste-biomass.

/pdf/production-characterization-and-evaluation-of-biochar-from-2s18nep7ej.pdf

Production, characterization and evaluation of biochar from pod (Pisum sativum), leaf (Brassica oleracea) and peel (Citrus sinensis) wastes

With the rise in global population and increased agricultural requirements comes an increasing need for freshwater. Currently, it is estimated that approximately 75% of fresh water consumption is for the growth of agricultural crops, and only 10% to 30% of this water is actually made available to plants. It is widely accepted that farming practices which rely heavily on chemical fertilizers and unsustainable land management practices have led in many regions to infertile sandy soils with reduced water holding capacity and insufficient amounts of organic matter. Combined with increasing global population, the need to better manage fresh water use, particularly agricultural usage, is paramount. The use of biochar as a soil amendment has been suggested as a way to increase water holding capacity, but only limited quantitative studies exist in terms of the effectiveness of biochar in increasing a soil's water holding capacity. The main purpose of this study was to determine the effect of woody biochar amendment (yellow pine from pyrolysis at 400°C) on the water holding capacity of loamy sand soil with different mixture rates. Results show a doubling in water holding capacity by mass using a 9% mixture of biochar (equivalent to 195 metric ton/ha), which is an agriculturally relevant concentration. High percentage mixtures of biochar increase water holding capacity dramatically. These results suggest the use of biochar has potential to mitigate drought and increase crop yields in loamy sand soil.

/pdf/impact-of-biochar-on-the-water-holding-capacity-of-loamy-4hjnv4rwzd.pdf

Impact of biochar on the water holding capacity of loamy sand soil

The research performed in this project focuses on the application of instruments including accelerometers and tiltmeters to monitor bridge scour. First, two large scale laboratory experiments were performed. One experiment is the simulation of a bridge with a shallow foundation, and the other is the simulation of a bridge with a deep foundation. A series of instruments were installed on the simulated bridge to monitor the performance of the bridge due to scour. Both the shallow foundation experiment and deep foundation experiment show that accelerometers and tiltmeters can be used in scour monitoring events since both give warning of bridge failure successfully. Subsequently, two individual monitoring systems were designed and installed on two bridges: US59 over Guadalupe River Bridge and SH80 over San Antonio River Bridge in Texas. Realtime data are collected and transmitted to a computer server at Texas A&M University, which can be accessed remotely. The instrumentation on the two bridges does not show great hope of application of accelerometers to monitor bridge scour because of a lack of sufficient excitation from traffic. Another issue with the accelerometers is the high power consumption during the transmission of accelerometer data, which cannot be satisfied with a typical solar panel and battery. Tiltmeters can provide the integral behavior of the bridge, and therefore are very useful devices for scour monitoring. Guidelines and protocols for scour monitoring based on the US59 over Guadalupe River Bridge and the SH80 over San Antonio River Bridge are provided in the study.

Realtime Monitoring of Bridge Scour Using Remote Monitoring Technology

Two of the most important resources in agriculture are soil and water. The quality of the soil determines the health and output of crops. Biochar has been recognized as being a useful soil amendment due to its perceived benefits of increasing water and nutrient retention. However, limited research has been conducted to compare the characteristics of biochar created from different feedstocks to determine which are the most effective at raising water holding capacity. This study compared the water holding capacity and chemical composition of biochar created from two different materials: eastern hemlock and switchblade grass. Results showed that both the hemlock char and switchblade grass char were able to significantly raise the water holding capacity of loamy sand. The switchblade grass increased the water holding capacity more than the hemlock biochar. For example, at a mixture rate of 10% biochar by weight, switchblade grass increased loamy sand's water holding capacity by 228%, compared with 133% for hemlock. The water holding capacity of the switchblade grass biochar alone was 448.69% of its weight and the hemlock biochar held 268.34% of its weight. These results suggest that switchblade grass may be better suited for improving water retention in sandy soils. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1474–1479, 2017

Characterization of biochar and its effects on the water holding capacity of loamy sand soil: Comparison of hemlock biochar and switchblade grass biochar characteristics

Development of A Drilling Expert System for Designing and Applying Successful Cement Jobs

Input data used in Multi-Attribute Decision Making (MADM) problems are often perceived to be imprecise by decision-makers because they are based on expert assessments. As a result, an important step in many applications of MADM is to perform a sensitivity analysis on the input data to help decision-makers understand how in which regions of the input data space they can be most confident in the recommended decisions and where improved input information is most needed. This paper describes sensitivity analysis procedures which will help decision-makers examine the robustness of the optimal solution to changes in input parameters in system selection decisions, where the system is made up of components (drilling technologies) that can be combined in many different ways. This paper presents two different sensitivity analysis methodologies. One is a sensitivity analysis for weighting factors of each attribute, and the other is a sensitivity analysis for uncertainty of overall attribute inputs. An application case study of the proposed approach is described to select optimal onshore Environmentally Friendly Drilling (EFD) systems at Green Lake near McFaddin, TX. © 2011 Wiley Periodicals, Inc. © 2012 Wiley Periodicals, Inc.

Ok-Youn Yu

Papers

Impact of biochar on the water holding capacity of loamy sand soil

Realtime Monitoring of Bridge Scour Using Remote Monitoring Technology

Characterization of biochar and its effects on the water holding capacity of loamy sand soil: Comparison of hemlock biochar and switchblade grass biochar characteristics

Development of A Drilling Expert System for Designing and Applying Successful Cement Jobs

Sensitivity analysis for multi-attribute system selection problems in onshore Environmentally Friendly Drilling (EFD)