Variable-rate application technologies in precision agriculture

Enhancing digital and precision agriculture is currently inevitable to overcome the economic and environmental challenges of the agriculture in the 21st century. The purpose of this study was to generate and compare management zones (MZ) based on the Sentinel-2 satellite data for variable rate application of mineral nitrogen in wheat production, calculated using different remote sensing (RS)-based models under varied soil, yield and crop data availability. Three models were applied, including (1) a modified “RS- and threshold-based clustering”, (2) a “hybrid-based, unsupervised clustering”, in which data from different sources were combined for MZ delineation, and (3) a “RS-based, unsupervised clustering”. Various data processing methods including machine learning were used in the model development. Statistical tests such as the Paired Sample T-test, Kruskal–Wallis H-test and Wilcoxon signed-rank test were applied to evaluate the final delineated MZ maps. Additionally, a procedure for improving models based on information about phenological phases and the occurrence of agricultural drought was implemented. The results showed that information on agronomy and climate enables improving and optimizing MZ delineation. The integration of prior knowledge on new climate conditions (drought) in image selection was tested for effective use of the models. Lack of this information led to the infeasibility of obtaining optimal results. Models that solely rely on remote sensing information are comparatively less expensive than hybrid models. Additionally, remote sensing-based models enable delineating MZ for fertilizer recommendations that are temporally closer to fertilization times.

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Clustering and Smoothing Pipeline for Management Zone Delineation Using Proximal and Remote Sensing

Sensors ◽

10.3390/s22020645 ◽

2022 ◽

Vol 22 (2) ◽

pp. 645

Author(s):

S. Hamed Javadi ◽

Angela Guerrero ◽

Abdul M. Mouazen

Keyword(s):

Feature Selection ◽

Precision Agriculture ◽

Input Data ◽

Clustering Algorithm ◽

Near Infrared ◽

Variable Rate ◽

Yield Data ◽

Data Format ◽

Variable Rate Application ◽

Cross Correlation Analysis

In precision agriculture (PA) practices, the accurate delineation of management zones (MZs), with each zone having similar characteristics, is essential for map-based variable rate application of farming inputs. However, there is no consensus on an optimal clustering algorithm and the input data format. In this paper, we evaluated the performances of five clustering algorithms including k-means, fuzzy C-means (FCM), hierarchical, mean shift, and density-based spatial clustering of applications with noise (DBSCAN) in different scenarios and assessed the impacts of input data format and feature selection on MZ delineation quality. We used key soil fertility attributes (moisture content (MC), organic carbon (OC), calcium (Ca), cation exchange capacity (CEC), exchangeable potassium (K), magnesium (Mg), sodium (Na), exchangeable phosphorous (P), and pH) collected with an online visible and near-infrared (vis-NIR) spectrometer along with Sentinel2 and yield data of five commercial fields in Belgium. We demonstrated that k-means is the optimal clustering method for MZ delineation, and the input data should be normalized (range normalization). Feature selection was also shown to be positively effective. Furthermore, we proposed an algorithm based on DBSCAN for smoothing the MZs maps to allow smooth actuating during variable rate application by agricultural machinery. Finally, the whole process of MZ delineation was integrated in a clustering and smoothing pipeline (CaSP), which automatically performs the following steps sequentially: (1) range normalization, (2) feature selection based on cross-correlation analysis, (3) k-means clustering, and (4) smoothing. It is recommended to adopt the developed platform for automatic MZ delineation for variable rate applications of farming inputs.

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Variable Rate Irrigation (VRI)

Manuali – Scienze Tecnologiche - SPARKLE - Entrepreneurship for Sustainable Precision Agriculture ◽

10.36253/978-88-5518-044-3.22 ◽

2020 ◽

pp. 22

Author(s):

João Coimbra ◽

José Rafael Marques da Silva ◽

Manuela Correia

Keyword(s):

Precision Agriculture ◽

Variable Rate ◽

Irrigation Technology ◽

Variable Rate Application ◽

Variable Rate Irrigation

Many types of technology are used in variable rate application for Precision Agriculture. In this case, we are talking about Variable Rate Irrigation technology. Materials for this topic include a presentation and a text, that are complementary.

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Variable Rate Application of Herbicides for Weed Management in Pre- and Postemergence

Pests, Weeds and Diseases in Agricultural Crop and Animal Husbandry Production ◽

10.5772/intechopen.93558 ◽

2020 ◽

Author(s):

Alessandro da Costa Lima ◽

Kassio Ferreira Mendes

Keyword(s):

Environmental Impact ◽

Precision Agriculture ◽

Weed Management ◽

Crop Productivity ◽

Variable Rate ◽

Chemical Management ◽

Variable Rate Application ◽

Skilled Workforce ◽

Investment Capacity

With the advent of precision agriculture, it was possible to integrate several technologies to develop the variable rate application (VRA). The use of VRA allows savings in the use of herbicides, better weed control, lower environmental impact and, indirectly, increased crop productivity. There are VRA techniques based on maps and sensors for herbicide application in preemergence (PRE) and postemergence (POST). The adoption of the type of system will depend on the investment capacity of the producer, skilled workforce available, and the modality of application. Although it still has some limitations, VRA has been widespread and has been occupying more and more space in chemical management, the tendency in the medium- and long term is that there is a gradual replacement of the conventional method of application. Given the benefits provided by VRA along with the engagement of companies and researchers, there will be constant evolution and improvement of this technology, cheapening the costs of implementation and providing its adoption by an increasing number of producers. Thus, the objective of this chapter was to address an overview of the use of herbicides in VRA for weed management in PRE and POST.

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Nitrogen replenishment using variable rate application technique in a small hand-harvested pear orchard

Spanish Journal of Agricultural Research ◽

10.5424/sjar/2017154-10986 ◽

2018 ◽

Vol 15 (4) ◽

pp. e0209 ◽

Cited By ~ 3

Author(s):

Anna Vatsanidou ◽

George D. Nanos ◽

Spyros Fountas ◽

John Baras ◽

Anamaria Castrignano ◽

...

Keyword(s):

Precision Agriculture ◽

Organic Matter Content ◽

Climatic Conditions ◽

Matter Content ◽

Management Approach ◽

Variable Rate ◽

Growing Seasons ◽

Variable Rate Application ◽

Small Hand ◽

Pear Orchard

Precision agriculture is a management approach for sustainable agriculture. It can be applied even in small fields. It aims to optimize inputs, improve profits, and reduce adverse environmental impacts. In this study, a series of measurements were conducted over three growing seasons to assess variability in a 0.55 ha pear orchard located in central Greece. Soil ECa was measured using EM38 sensor, while soil samples were taken from a grid 17 × 8 m and analysed for texture, pH, P, K, Mg, CaCO3, and organic matter content. Data analysis indicated that most of the nutrients were at sufficient levels. Soil and yield maps showed considerable variability while fruit quality presented small variations across the orchard. Yield fluctuations were observed, possibly due to climatic conditions. Prescription maps were developed for nitrogen variable rate application (VRA) for two years based on the replacement of the nutrients removed by the crop. VRA application resulted in 56% and 50% reduction of N fertiliser compared to uniform application.

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Evaluation of Centrifugal Spreader Response to Variable Rate Application by Using Task File Data

IFAC-PapersOnLine ◽

10.1016/j.ifacol.2020.12.213 ◽

2020 ◽

Vol 53 (2) ◽

pp. 15804-15809

Author(s):

Galibjon M. Sharipov ◽

Andreas Heiß ◽

Hans W. Griepentrog ◽

Dimitrios S. Paraforos

Keyword(s):

Variable Rate ◽

Variable Rate Application

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A Path Model of the Intention to Adopt Variable Rate Irrigation in Northeast Italy

Sustainability ◽

10.3390/su13041879 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1879

Author(s):

Maurizio Canavari ◽

Marco Medici ◽

Rungsaran Wongprawmas ◽

Vilma Xhakollari ◽

Silvia Russo

Keyword(s):

Technology Acceptance ◽

Precision Agriculture ◽

Ease Of Use ◽

Perceived Usefulness ◽

Path Model ◽

Irrigated Agriculture ◽

Variable Rate ◽

Intention To Adopt ◽

Factors Influencing ◽

Variable Rate Irrigation

Irrigated agriculture determines large blue water withdrawals, and it is considered a key intervention area to reach sustainable development objectives. Precision agriculture technologies have the potential to mitigate water resource depletion that often characterises conventional agricultural approaches. This study investigates the factors influencing farmers’ intentions to adopt variable rate irrigation (VRI) technology. The Technology Acceptance Model 3 (TAM-3) was employed as a theoretical framework to design a survey to identify the factors influencing farmers’ decision-making process when adopting VRI. Data were gathered through quantitative face-to-face interviews with a sample of 138 fruit and grapevine producers from the Northeast of Italy (Veneto, Emilia-Romagna, Trentino-Alto Adige, Friuli-Venezia Giulia). Data were analysed using partial least squares path modelling (PLS-PM). The results highlight that personal attitudes, such as perceived usefulness and subjective norm, positively influence the intention to adopt VRI. Additionally, the perceived ease of use positively affects intention, but it is moderated by subject experience.

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The sensitivity of economic gains from high-speed planting

Advances in Animal Biosciences ◽

10.1017/s2040470017001169 ◽

2017 ◽

Vol 8 (2) ◽

pp. 662-667

Author(s):

C. R. Dillon ◽

J. Shockley ◽

T. Mark

Keyword(s):

Optimization Model ◽

Technological Progress ◽

High Speed ◽

Operating Cost ◽

Cost Savings ◽

Variable Rate ◽

Net Returns ◽

Variable Rate Application ◽

Technology Changes ◽

Profit Potential

Recent technological progress in high-speed planting (HSP) warrants economic analysis of its potential. A whole farm optimization model of a 1000 ha Kentucky, USA corn and soybean operation finds that operating cost savings (labor, fuel, tractor repairs) and yield increases couple in recovering annual ownership costs of HSP technology. Changes in farm net returns are positive for all 12-row planter scenarios and all double speed cases for the 16-row planter but not for a 50% increase in speed with the 16-row planter. The greatest profit potential occurred when adopting the combination of HSP and variable rate application (VRA), with increased net returns of up to 6.57% compared to conventional speed no VRA for the 12-row planter.

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