Yield-Based Management Zones and Grid Sampling Strategies: Describing Soil Test and Nutrient Variability

2005 ◽  
Vol 97 (3) ◽  
pp. 968-982 ◽  
Author(s):  
Michael Flowers ◽  
Randall Weisz ◽  
Jeffrey G. White
Keyword(s):  
Soil Test ◽  
Sampling Strategies ◽  
Management Zones ◽  
Grid Sampling ◽  
Nutrient Variability

A comparison of soil sampling procedures used to monitor soil fertility in permanent pastures

Soil Research ◽  
1984 ◽  
Vol 22 (1) ◽  
pp. 81 ◽  
Author(s):  
DK Friesen ◽  
GJ Blair
Keyword(s):  
Sampling Method ◽  
Nutrient Status ◽  
Temporal Variations ◽  
Cluster Sampling ◽  
Soil Test ◽  
Sampling Strategies ◽  
Grazed Pasture ◽  
The Mean ◽  
Sampling Procedures ◽  
Bray 1

Soil testing programs are often brought in disrepute by unexplained variability in the data. The deposition of dung and urine onto grazed pasture brings about marked variation in the chemical status of soils which contributes to this variability. A study was undertaken to compare a range of sampling procedures to estimate Colwell-P, Bray-1 P, bicarbonate K and pH levels in adjacent low and high P status paddocks. The sampling strategies used consisted of 75 by 50 m grids; whole and stratified paddock zig-zag and cluster (monitor plot) samplings. Soil test means for the various parameters did not vary among sampling methods. The number of grid samples required to estimate within 10% of the mean varied from 121 for Bray-1 P down to 1 for soil pH. Sampling efficiencies were higher for cluster sampling than for whole paddock zig-zag path sampling. Stratification generally did not improve sampling efficiency in these paddocks. Soil test means declined as sampling depth increased, but the coefficient of variation remained constant for Colwell-P and pH. The results indicate that cluster sampling (monitor plots) is the most appropriate procedure for estimating the nutrient status of grazed pastures. This sampling method enables a more accurate measure to be taken of the nutrient status of a paddock and should allow more reasonable estimates to be made of the temporal variations in soil test.

Incremental Grid Sampling Strategies in Robotics

2005 ◽  
pp. 313-328 ◽  
Author(s):  
Stephen R. Lindemann ◽  
Anna Yershova ◽  
Steven M. LaValle
Keyword(s):  
Sampling Strategies ◽  
Grid Sampling

scholarly journals Determining Land Management Zones Using Pedo-Geomorphological Factors in Potential Degraded Regions to Achieve Land Degradation Neutrality

Land ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 92 ◽  
Author(s):  
Ali Keshavarzi ◽  
Vinod Kumar ◽  
Eduardo Leonel Bottega ◽  
Jesús Rodrigo-Comino
Keyword(s):  
Land Management ◽  
Land Degradation ◽  
Agricultural Land ◽  
Clay Content ◽  
Sampling Point ◽  
Management Zones ◽  
Grid Sampling ◽  
Flow Vector ◽  
Management Plans ◽  
Flow Vectors

The proper delineation of site-specific management zones is very important in the agricultural land management of potentially degraded areas. There is a necessity for the development of prospective tools in management plans to correctly understand the land degradation processes. In order to accomplish this, we present a pedo-geomorphological approach using soil texture, land elevation and flow vector aspects to distinguish different management zones and to discretize soil micronutrients. To achieve this goal, we conducted the study in the Neyshabur plain, Northeast Iran. For data collection, grid sampling (500 × 500 m) was used with 70 specific points. Soil samples were collected in triplicates from various sites as composite samples (0–30 cm) to analyse clay, Zn, Mn, Cu and Fe. Using the altitude information (obtained with GPS at each sampling point), flow vectors were also modelled for all selected points. Based on the values of altitude, flow vectors and clay, management zones were delimited using geographic information systems. The best data organization was obtained from the combination of clay + elevation + flow vector attributes, generating two different management zones. In this circumstance, the lowest fuzzy performance index (FPI) and modified partition entropy (MPE) values were generated. It can be observed that the management zone 1 (MZ1) is located in the areas with a lower elevation and higher content of clay. On the other hand, the MZ2 was characterized by areas with a higher elevation and lower clay content. This study concluded that the design of management zones, using pedo-geomorphological information could reduce the time and cost of sampling necessary to assess potentially degraded areas of land.

scholarly journals Estimating Pollution Loads in Snow Removed from a Port Facility: Snow Pile Sampling Strategies

2021 ◽  
Vol 232 (2) ◽  
Author(s):  
Arya Vijayan ◽  
Heléne Österlund ◽  
Jiri Marsalek ◽  
Maria Viklander
Keyword(s):  
Sampling Strategy ◽  
Sampling Strategies ◽  
Grid Sampling ◽  
Pollutant Loads ◽  
Pollutant Concentrations ◽  
Port Area ◽  
Guideline Values ◽  
Mass Load ◽  
Entire Depth ◽  
Composite Samples

AbstractChoosing the appropriate sampling strategy is significant while estimating the pollutant loads in a snow pile and assessing environmental impacts of dumping snow into water bodies. This paper compares different snow pile sampling strategies, looking for the most efficient way to estimate the pollutant loads in a snow pile. For this purpose, 177 snow samples were collected from nine snow piles (average pile area − 30 m2, height − 2 m) during four sampling occasions at Frihamnen, Ports of Stockholm’s port area. The measured concentrations of TSS, LOI, pH, conductivity, and heavy metals (Zn, Cu, Cd, Cr, Pb, and V) in the collected samples indicated that pollutants are not uniformly distributed in the snow piles. Pollutant loads calculated from different sampling strategies were compared against the load calculated using all samples collected for each pile (best estimate of mass load, BEML). The results/study showed that systematic grid sampling is the best choice when the objective of sampling is to estimate the pollutant loads accurately. Estimating pollutant loads from single snow column samples (collected at a point from the snow pile through the entire depth of the pile) produced up to 400% variation from BEML, whereas samples composed by mixing volume-proportional subsamples from all samples (horizontal composite samples) produced only up to 50% variation. Around nine samples were required to estimate the pollutant loads within 50% deviation from BEML for the studied snow piles. Converting pollutant concentrations in snow to equivalent concentrations in snowmelt and comparing it with available guideline values for receiving water, Zn was identified as the critical pollutant.

scholarly journals Comparative analysis of soil-sampling methods used in precision agriculture

2021 ◽  
Author(s):  
José Roberto Moreira Ribeiro Gonçalves ◽  
Gabriel Araújo e Silva Ferraz ◽  
Étore Francisco Reynaldo ◽  
Diego Bedin Marin ◽  
Patrícia Ferreira Ponciano Ferraz ◽  
...  
Keyword(s):  
Precision Agriculture ◽  
Agricultural Production ◽  
Sampling Methods ◽  
Soil Sampling ◽  
Soil Electrical Conductivity ◽  
Production Environment ◽  
Management Zones ◽  
Grid Sampling ◽  
Soil Sensors ◽  
Significant Difference

The aim of this study was to compare three different soil-sampling methods used in Precision Agriculture and their environmental impact in the agricultural production environment. The sampling methods used were: management zones by elevation (MZA), grid sampling (GS), and sampling oriented by apparent soil electrical conductivity (OS). It was tested in three different fields. When the recommendations were compared, a significant difference among the suggested dosages was observed, indicating the need to improve the soil-sampling techniques, since there were doubts about input deficits or overdoses, regardless of the technology studied. The GS method was the most environmentally viable alternative for P compared to other methods and the OS presented as the better option for K and N. However, the use of soil sensors has been shown to be a viable technology that needs further improvement in order to improve productivity and, hence, economic and environmental gains.

scholarly journals Economic evaluation of variable rate nitrogen management of canola for zones based on historical yield maps and soil test recommendations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mohammad Khakbazan ◽  
Alan Moulin ◽  
Jianzhong Huang
Keyword(s):  
Yield Function ◽  
Nitrogen Management ◽  
Soil Test ◽  
Western Canada ◽  
Management Zones ◽  
Positive Effects ◽  
Efficient Management ◽  
Net Revenue ◽  
N Management ◽  
N Rates

AbstractCanola (Brassica napus L.) is a highly valuable crop for Canada’s economy, making the efficient management of canola a priority. A field-scale study was conducted at ten sites between 2014 and 2016 to evaluate the viability of site specific nitrogen (N) management zones (MZ) based on analysis of historical yield maps and soil test recommendations to improve canola productivity and profitability in western Canada. Treatments included factorial combinations of three canola yield zones (low, average, high) by four N rates, replicated four times at each site. The canola yield function had a quadratic form in each field but the effects of MZ varied between fields with positive effects in only a few fields. When ten site-years data were combined, MZ had positive effects on canola performance. On average, MZ of N fertilizer over ten fields generated between $28 to $65 ha−1 more net revenue (NR) relative to average yield management. Site-years, which reflect farm management and other farm characteristics had significant effects on yield and NR ranging from − $91 to $352 ha−1 compared to a baseline. Nitrogen application under MZs was only reduced by 8% compared to uniform rates. The potential for MZ does exist; however, its effectiveness is highly variable.

scholarly journals Spatial variability of soil properties under different landuse in Koupendri catchment, Benin

2020 ◽  
Vol 10 ◽  
Author(s):  
Chukwuebuka Vincent Azuka ◽  
Attanda Mouinou Igué
Keyword(s):  
Land Use ◽  
Soil Properties ◽  
Rice Field ◽  
Available Phosphorus ◽  
Management Zones ◽  
North West ◽  
Grid Sampling ◽  
Land Use Types ◽  
Spherical Models ◽  
Effect Ratio

The spatial distribution of soil properties especially saturated hydraulic conductivity (Ksat), Bulk density (BD), soil organic carbon (SOC), total nitrogen (TN) and available phosphorus (Avail.P) is fundamental to sustainable management of soil resources. About 291 surface soil (0-20 cm) samples were collected across three land use types (maize-sorghum (MS), rice field and fallow shrub-grassland (FSG) in Koupendri, north-west Benin using a grid sampling of 25 m x 25 m supplemented with samplings at 5 m x 5 m. Data obtained were subjected to classical and spatial statistics, Pearson’s correlation and analysis of variance using GENSTAT. The soil properties showed normal and non-normal distribution, variation was high (75-126.7 %) for Ksat, moderate (29-45 %) for SOC, C/N and Avail.P, and low (7-15) for BD and TN across the land use. Land use had significant (P &lt; 0.05) effect on all the soil properties evaluated except C/N. The highest values of Ksat (151.6 cm/d), SOC (1.26 %), BD (1.79 g/cm<sup>3</sup>), TN (0.105 %), Avail.P (4.66 ppm) and C/N (12.14) were obtained under the MS cropland whereas porosity was highest (43.7 %) in the rice field. High significant correlation (P &lt; 0.01) was observed among the soil properties irrespective of land use.  The correlation length (65-300 m) and nugget effect ratio indicates high variation and strong spatially dependent soil properties. However, TN, BD, Avail.P and C/N were weakly spatially dependent. The variograms were fitted with mostly exponential and spherical models. The interpolation map could help in delineating different management zones and for making good agronomic decisions.

Spatial and temporal variation in soil inorganic n concentration, and soil test P and K, in red raspberry fields and implications for soil sampling strategies

2002 ◽  
Vol 82 (3) ◽  
pp. 355-364 ◽  
Author(s):  
B J Zebarth ◽  
D M Dean ◽  
C G Kowalenko ◽  
J W Paul ◽  
K. Chipperfield
Keyword(s):  
Sampling Strategy ◽  
Systematic Sampling ◽  
Soil Test ◽  
Sampling Strategies ◽  
Red Raspberry ◽  
Inorganic N ◽  
N Concentration ◽  
Soil Inorganic N ◽  
Soil Test P ◽  
Soil Inorganic

Fertilizer is commonly applied as a band in red raspberry (Rubus idaeus L.) fields, resulting in complex spatial and temporal variation in soil inorganic N concentration, and in soil test P and K. The objectives of this study were to determine the spatial and temporal distribution of soil inorganic N in red raspberry fields receiving different N fertility treatments, to use the data to determine the most appropriate sampling strategies for estimating the quantity of soil inorganic N at various times during the growing season, and to evaluate the same sampling strategies for soil test P and K. Treatments were a control that received no manure or fertilizer N, 55 kg N ha-1 as urea or as Duration T60, a slow release N fertilizer, banded in mid-April, or 100 kg total N ha-1 as solid broiler manure broadcast or banded in early March, or banded in mid-April. Soil inorganic N was sampled at 10 inter-row locations 8, 23, 38, 53, 68, 83, 98, 113, 128, and 143 cm from the crop row, and for 0–15, 15–30, and 30–60 cm depth, for four sampling dates for the control and urea treatments, and for 0–15 and 15–30 cm depth on one sampling date for the remaining treatments. Random sampling and four systematic sampling strategies were evaluated for their bias in estimating soil inorganic N concentration and soil test P and K, and with respect to the number of soil cores required to achieve a given precision and probability level combination. The random sampling strategy gave unbiased estimates of soil inorganic N and soil test P and K, however, the number of cores required to obtain a given precision at a given probability level were generally greater than for the systematic sampling strategies. The systematic sampling strategy involving sampling only in the crop row and in the centre of the inter-row, the current industry standard, gave expected values that could sometimes be substantially lower than the true value, and was therefore not recommended for use in raspberry fields. The best systematic sampling strategy used samples collected from the crop row, from the fertilizer band, from the centre of the inter-row, and from midway between the fertilizer band and the centre of the inter-row. Key words: Rubus idaeus, nitrate leaching, nitrification, nitrate, ammonium

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