scholarly journals Local versus field scale soil heterogeneity characterization – a challenge for representative sampling in pollution studies

SOIL ◽  
2015 ◽  
Vol 1 (2) ◽  
pp. 695-705 ◽  
Author(s):  
Z. Kardanpour ◽  
O. S. Jacobsen ◽  
K. H. Esbensen
Keyword(s):  
Large Scale ◽  
Environmental Chemistry ◽  
Soil Heterogeneity ◽  
Environmental Pollutant ◽  
Small Scale ◽  
Compositional Variation ◽  
Sampling Point ◽  
Representative Sampling ◽  
Research Areas ◽  
Theory Of Sampling

Abstract. This study is a contribution to development of a heterogeneity characterization facility for "next-generation" soil sampling aimed, for example, at more realistic and controllable pesticide variability in laboratory pots in experimental environmental contaminant assessment. The role of soil heterogeneity in quantification of a set of exemplar parameters is described, including a brief background on how heterogeneity affects sampling/monitoring procedures in environmental pollutant studies. The theory of sampling (TOS) and variographic analysis has been applied to develop a more general fit-for-purpose soil heterogeneity characterization approach. All parameters were assessed in large-scale transect (1–100 m) vs. small-scale (0.1–0.5 m) replication sampling point variability. Variographic profiles of experimental analytical results from a specific well-mixed soil type show that it is essential to sample at locations with less than a 2.5 m distance interval to benefit from spatial auto-correlation and thereby avoid unnecessary, inflated compositional variation in experimental pots; this range is an inherent characteristic of the soil heterogeneity and will differ among other soils types. This study has a significant carrying-over potential for related research areas, e.g. soil science, contamination studies, and environmental monitoring and environmental chemistry.

scholarly journals Local versus field scale soil heterogeneity characterization – a challenge for representative sampling in pollution studies

2015 ◽  
Vol 2 (1) ◽  
pp. 619-645
Author(s):  
Z. Kardanpour ◽  
O. S. Jacobsen ◽  
K. H. Esbensen
Keyword(s):  
Large Scale ◽  
Environmental Chemistry ◽  
Soil Heterogeneity ◽  
Environmental Pollutant ◽  
Soil Microbiology ◽  
Small Scale ◽  
Compositional Variation ◽  
Representative Sampling ◽  
Research Areas ◽  
Organic Matter Loss

Abstract. This study is a contribution to development of a heterogeneity characterisation facility for "next generation" sampling aimed at more realistic and controllable pesticide variability in laboratory pots in experimental environmental contaminant assessment. The role of soil heterogeneity on quantification of a set of exemplar parameters, organic matter, loss on ignition (LOI), biomass, soil microbiology, MCPA sorption and mineralization is described, including a brief background on how heterogeneity affects sampling/monitoring procedures in environmental pollutant studies. The Theory of Sampling (TOS) and variographic analysis has been applied to develop a fit-for-purpose heterogeneity characterization approach. All parameters were assessed in large-scale profile (1–100 m) vs. small-scale (0.1–1 m) replication sampling pattern. Variographic profiles of experimental analytical results concludes that it is essential to sample at locations with less than a 2.5 m distance interval to benefit from spatial auto-correlation and thereby avoid unnecessary, inflated compositional variation in experimental pots; this range is an inherent characteristic of the soil heterogeneity and will differ among soils types. This study has a significant carrying-over potential for related research areas e.g. soil science, contamination studies, and environmental monitoring and environmental chemistry.

scholarly journals Integrating the Theory of Sampling into Underground Mine Grade Control Strategies: Case Studies from Gold Operations

Minerals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 238
Author(s):  
Dominy ◽  
Glass ◽  
O’Connor ◽  
Lam ◽  
Purevgerel
Keyword(s):  
Case Studies ◽  
Control Strategies ◽  
Control Process ◽  
Control Programme ◽  
Small Scale ◽  
Sampling Errors ◽  
Sample Collection ◽  
Representative Sampling ◽  
Grade Control ◽  
Theory Of Sampling

Grade control aims to deliver adequately defined tonnes of ore to the process plant. The foundation of any grade control programme is collecting high-quality samples within a geological context. The requirement for quality samples has long been recognised, in that these should be representative and fit-for-purpose. Correct application of the Theory of Sampling reduces sampling errors across the grade control process, in which errors can propagate from sample collection through sample preparation to assay results. This contribution presents three case studies which are based on coarse gold-dominated orebodies. These illustrate the challenges and potential solutions to achieve representative sampling and build on the content of a previous publication. Solutions ranging from bulk samples processed through a plant to whole-core sampling and assaying using bulk leaching, are discussed. These approaches account for the nature of the mineralisation, where extreme gold particle-clustering effects render the analysis of small-scale samples highly unrepresentative. Furthermore, the analysis of chip samples, which generally yield a positive bias due to over-sampling of quartz vein material, is discussed.

Sample Quality Criteria

2015 ◽  
Vol 98 (2) ◽  
pp. 265-268 ◽  
Author(s):  
Charles A Ramsey ◽  
Claas Wagner
Keyword(s):  
Confidence Level ◽  
Large Scale ◽  
Analytical Data ◽  
Quality Criteria ◽  
Small Scale ◽  
Sampling Effort ◽  
Sample Collection ◽  
Representative Sampling ◽  
Sample Quality ◽  
Incorrect Decision

Abstract The concept of Sample Quality Criteria (SQC) is the initial step in the scientific approach to representative sampling. It includes the establishment of sampling objectives, Decision Unit (DU), and confidence. Once fully defined, these criteria serve as input, in addition to material properties, to the Theory of Sampling for developing a representative sampling protocol. The first component of the SQC establishes these questions: What is the analyte(s) of concern? What is the concentration level of interest of the analyte(s)? How will inference(s) be made from the analytical data to the DU? The second component ofthe SQC establishes the DU, i.e., the scale at whichdecisions are to be made. On a large scale, a DU could be a ship or rail car; examples for small-scale DUs are individual beans, seeds, or kernels. A well-defined DU is critical because it defines the spatialand temporal boundaries of sample collection. SQC are not limited to a single DU; they can also include multiple DUs. The third SQC component, the confidence, establishes the desired probability that a correct inference (decision) can be made. The confidence level should typically correlate to the potential consequences of an incorrect decision (e.g., health or economic). The magnitude of combined errors in the sampling, sample processing and analytical protocols determines the likelihood of an incorrect decision. Thus, controlling error to a greater extent increases the probability of a correct decision. The required confidence level directly affects the sampling effort and QC measures.

Computing within limits and ICTD

First Monday ◽  
2015 ◽  
Author(s):  
Jay Chen
Keyword(s):  
Low Power ◽  
Communication Technology ◽  
High Performance ◽  
Large Scale ◽  
Information Communication Technology ◽  
Small Scale ◽  
Information Communication ◽  
Research Areas

Computing research today is fixated on high performance and large scale, but computing can be tremendously powerful even at low power and small scale. In this article we present a perspective on promising directions for research on computing within limits, where concerns about limits overshadow performance and scale. Despite coming from different motivations, computing within limits has very similar considerations as Information Communication Technology for Development (ICTD). We discuss where the two research areas intersect and where they may diverge. We draw parallels between computing within limits and ICTD in terms of technical constraints, designing for context, and goals. We hope to help stimulate computing within limits with ideas from ICTD and highlight research synergies.

scholarly journals Small scale spatial heterogeneity of soil respiration in an old growth temperate deciduous forest

2009 ◽  
Vol 6 (5) ◽  
pp. 9977-10005 ◽  
Author(s):  
A. Jordan ◽  
G. Jurasinski ◽  
S. Glatzel
Keyword(s):  
Soil Moisture ◽  
Soil Respiration ◽  
Soil Temperature ◽  
Spatial Heterogeneity ◽  
Large Scale ◽  
Stand Structure ◽  
Small Scale ◽  
Sampling Point ◽  
Old Growth ◽  
Old Growth Forest

Abstract. The large scale spatial heterogeneity of soil respiration caused by differences in site conditions is quite well understood. However, comparably little is known about the micro scale heterogeneity within forest ecosystems on homogeneous soils. Forest age, soil texture, topographic position, micro topography and stand structure may influence soil respiration considerably within short distance. In the present study within site spatial heterogeneity of soil respiration has been evaluated. To do so, an improvement of available techniques for interpolating soil respiration data via kriging was undertaken. Soil respiration was measured with closed chambers biweekly from April 2005 to April 2006 using a nested design (a set of stratified random plots, supplemented by 2 small and 2 large nested groupings) in an unmanaged, beech dominated old growth forest in Central Germany (Hainich, Thuringia). A second exclusive randomized design was established in August 2005 and continually sampled biweekly until July 2007. The average soil respiration values from the random plots were standardized by modeling soil respiration data at defined soil temperature and soil moisture values. By comparing sampling points as well as by comparing kriging results based on various sampling point densities, we found that the exclusion of local outliers was of great importance for the reliability of the estimated fluxes. Most of this information would have been missed without the nested groupings. The extrapolation results slightly improved when additional parameters like soil temperature and soil moisture were included in the extrapolation procedure. Semivariograms solely calculated from soil respiration data show a broad variety of autocorrelation distances (ranges) from a few centimeters up to a few tens of meters. The combination of randomly distributed plots with nested groupings plus the inclusion of additional relevant parameters like soil temperature and soil moisture data permits an improved estimation of the range of soil respiration, which is a prerequisite for reliable interpolated maps of soil respiration.

The influence of soil heterogeneity on exploratory tunnelling by the subterranean termite Coptotermes frenchi (Isoptera: Rhinotermitidae)

2003 ◽  
Vol 93 (5) ◽  
pp. 413-423 ◽  
Author(s):  
T.A. Evans
Keyword(s):  
Water Conservation ◽  
Field Data ◽  
Large Scale ◽  
Laboratory Experiments ◽  
Field Studies ◽  
Soil Heterogeneity ◽  
Large Field ◽  
Small Scale ◽  
Scale Field ◽  
Large Scale Field

AbstractThe exploration of sand-filled arenas by workers of an entire colony of the Australian, subterranean foraging, tree-nesting termite, Coptotermes frenchi Hill was investigated under laboratory conditions. The first experiment tested whether termite exploration of sand was influenced by the presence of gaps or objects in the sand. Gaps and objects were chosen to represent soil heterogeneity in the urban environment: gaps to represent tunnels dug by other animals, perspex strips to represent cables and pipes, and wood strips to represent roots. Termites always chose to explore gaps thoroughly before they began tunnelling in the sand. Significantly more and longer tunnels were excavated from the end of gaps at the far end of the arenas, and relatively little tunnelling occurred around and along objects. Termite density was significantly greater around and along wood compared with perspex blocks. The second experiment tested whether termite exploratory tunnelling was influenced by soil moisture. The termites tunnelled slowly in dry sand, but after discovering a patch of wet sand, increased tunnelling five-fold until it was completely explored, after which activity declined. Energy and water conservation may be behind these patterns of exploratory tunnelling as well as those seen in large field studies, but caution is urged when interpreting small scale laboratory experiments to explain large scale field data.

scholarly journals PERFORMANCE OF RPL PROTOCOL BASED ON NEW OBJECTIVE FUNCTION FOR IOT-WSN

2020 ◽  
Vol 3 (2) ◽  
pp. 21-34
Author(s):  
Zahraa A. Hamodi ◽  
Abdulkareem A. Kadhim
Keyword(s):  
Objective Function ◽  
Routing Protocol ◽  
Large Scale ◽  
Wireless Sensor ◽  
Small Scale ◽  
Energy Efficient Routing ◽  
Average Delay ◽  
Research Areas ◽  
Main Challenge ◽  
Scale Network

The development of routing protocol to manage energy consumption of wireless sensor devices is one of the active research areas. The main challenge is the resource constraint (e.g. energy). In Internet of Things (IoT), the devices operate in the presence of these limitations. Thus, an energy-efficient routing protocol is required. Routing Protocol for Low-Power and Lossy Network (RPL) is already introduced to enable IoT over Wireless Sensor Network. In this paper, a modified routing protocol depending on the maximum number of parent objective function (MNP-OF) is proposed. MNP-OF uses a new node metric called Neighboring-metric (N-metric). The proposed protocol is called MNP based on Remaining Energy (MRE) that combines N-metric with the node remaining energy metric for all nodes to the root node to select the preferred path. The results showed that MRE achieved up to 94% energy saving compared to RPL protocol in medium and large scale networks, while a reduction of about 33% in average remaining energy in small scale network. MRE showed considerable reductions in the average delay and the number of dead nodes combined with improvements in throughput, number of control messages, and number of switching parents for small scale network.

Small-Scale Science to Large-Scale Profession

2000 ◽  
Vol 45 (4) ◽  
pp. 396-398
Author(s):  
Roger Smith
Keyword(s):  
Large Scale ◽  
Small Scale

Development of Physics Learning Module Based on Guided Inquiry with Light Wave Material in Class XI of Senior High School

2020 ◽  
Vol 1 (1) ◽  
pp. 1-10
Author(s):  
Evi Rahmawati ◽  
Irnin Agustina Dwi Astuti ◽  
N Nurhayati
Keyword(s):  
Large Scale ◽  
Learning Strategy ◽  
Student Response ◽  
Average Score ◽  
Small Scale ◽  
Design Development ◽  
Teacher Response ◽  
Student Responses ◽  
Analysis Design ◽  
Scientific Skills

IPA Integrated is a place for students to study themselves and the surrounding environment applied in daily life. Integrated IPA Learning provides a direct experience to students through the use and development of scientific skills and attitudes. The importance of integrated IPA requires to pack learning well, integrated IPA integration with the preparation of modules combined with learning strategy can maximize the learning process in school. In SMP 209 Jakarta, the value of the integrated IPA is obtained from 34 students there are 10 students completed and 24 students are not complete because they get the value below the KKM of 68. This research is a development study with the development model of ADDIE (Analysis, Design, Development, Implementation, and Evaluation). The use of KPS-based integrated IPA modules (Science Process sSkills) on the theme of rainbow phenomenon obtained by media expert validation results with an average score of 84.38%, average material expert 82.18%, average linguist 75.37%. So the average of all aspects obtained by 80.55% is worth using and tested to students. The results of the teacher response obtained 88.69% value with excellent criteria. Student responses on a small scale acquired an average score of 85.19% with highly agreed criteria and on the large-scale student response gained a yield of 86.44% with very agreed criteria. So the module can be concluded receiving a good response by the teacher and students.

Planetary gentrification and urban (re)development

2019 ◽  
Vol 61 (1) ◽  
pp. 5-13 ◽  
Author(s):  
Loretta Lees
Keyword(s):  
Low Income ◽  
Policy Making ◽  
Large Scale ◽  
Urban Redevelopment ◽  
Urban Transformation ◽  
Small Scale ◽  
Income Groups ◽  
Low Income Groups

Abstract Gentrification is no-longer, if it ever was, a small scale process of urban transformation. Gentrification globally is more often practised as large scale urban redevelopment. It is state-led or state-induced. The results are clear – the displacement and disenfranchisement of low income groups in favour of wealthier in-movers. So, why has gentrification come to dominate policy making worldwide and what can be done about it?

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