Estimation of Biomass and Canopy Height in Bermudagrass, Alfalfa, and Wheat Using Ultrasonic, Laser, and Spectral Sensors

Non-destructive biomass estimation of vegetation has been performed via remote sensing as well as physical measurements. An effective method for estimating biomass must have accuracy comparable to the accepted standard of destructive removal. Estimation or measurement of height is commonly employed to create a relationship between height and mass. This study examined several types of ground-based mobile sensing strategies for forage biomass estimation. Forage production experiments consisting of alfalfa (Medicago sativa L.), bermudagrass [Cynodon dactylon (L.) Pers.], and wheat (Triticum aestivum L.) were employed to examine sensor biomass estimation (laser, ultrasonic, and spectral) as compared to physical measurements (plate meter and meter stick) and the traditional harvest method (clipping). Predictive models were constructed via partial least squares regression and modeled estimates were compared to the physically measured biomass. Least significant difference separated mean estimates were examined to evaluate differences in the physical measurements and sensor estimates for canopy height and biomass. Differences between methods were minimal (average percent error of 11.2% for difference between predicted values versus machine and quadrat harvested biomass values (1.64 and 4.91 t·ha−1, respectively), except at the lowest measured biomass (average percent error of 89% for harvester and quad harvested biomass < 0.79 t·ha−1) and greatest measured biomass (average percent error of 18% for harvester and quad harvested biomass >6.4 t·ha−1). These data suggest that using mobile sensor-based biomass estimation models could be an effective alternative to the traditional clipping method for rapid, accurate in-field biomass estimation.

[1]  S. Ustin,et al.  Hyperspectral canopy sensing of paddy rice aboveground biomass at different growth stages , 2014 .

[2]  Mark Dougherty,et al.  Calibration and use of plate meter regressions for pasture mass estimation in an Appalachian silvopasture , 2013 .

[3]  Compton J. Tucker,et al.  A critical review of remote sensing and other methods for non-destructive estimation of standing crop biomass , 1980 .

[4]  Samsuzana Abd Aziz,et al.  Ultrasonic Sensing for Corn Plant Canopy Characterization , 2004 .

[5]  Joy B. Zedler,et al.  Effects of sampling teams and estimation methods on the assessment of plant cover , 2003 .

[6]  Jordi Llorens,et al.  Performance of an Ultrasonic Ranging Sensor in Apple Tree Canopies , 2011, Sensors.

[7]  Eduardo Segarra,et al.  Spatial and Temporal Variability of Corn Growth and Grain Yield , 2002 .

[8]  A. Saxton A Macro for Converting Mean Separation Output to Letter Groupings in PROC MIXED , 1998 .

[9]  Tobias Würschum,et al.  Potential of genomic selection in rapeseed (Brassica napus L.) breeding , 2014 .

[10]  K. Omasa,et al.  Estimating vertical plant area density profile and growth parameters of a wheat canopy at different growth stages using three-dimensional portable lidar imaging , 2009 .

[11]  Josef Hakl,et al.  The use of a rising plate meter to evaluate lucerne (Medicago sativa L.) height as an important agronomic trait enabling yield estimation , 2012 .

[12]  Jon T. Biermacher,et al.  Production and Economics of Steers Grazing Tall Fescue with Annual Legumes or Fertilized with Nitrogen , 2012 .

[13]  Marvin L. Stone,et al.  Chlorophyll Estimation Using Multispectral Reflectance and Height Sensing , 2007 .

[14]  Jeffrey S. Fehmi,et al.  A plate meter inadequately estimated herbage mass in a semi-arid grassland. , 2009 .

[15]  P. Radtke,et al.  Detailed Stem Measurements of Standing Trees from Ground-Based Scanning Lidar , 2006, Forest Science.

[16]  C. Field,et al.  Relationships Between NDVI, Canopy Structure, and Photosynthesis in Three Californian Vegetation Types , 1995 .

[17]  David A. Norton,et al.  Comparison of Two Sampling Methods for Quantifying Changes in Vegetation Composition Under Rangeland Development , 2010 .

[18]  Ryan Gosselin,et al.  A Bootstrap-VIP approach for selecting wavelength intervals in spectral imaging applications , 2010 .

[19]  Laura Chasmer,et al.  Towards a universal lidar canopy height indicator , 2006 .

[20]  C. Jun,et al.  Performance of some variable selection methods when multicollinearity is present , 2005 .

[21]  Robert S. Arkle,et al.  Performance of Quantitative Vegetation Sampling Methods Across Gradients of Cover in Great Basin Plant Communities , 2013 .

[22]  B. Mistele,et al.  Comparison of active and passive spectral sensors in discriminating biomass parameters and nitrogen status in wheat cultivars , 2011 .

[23]  Tahir Mehmood,et al.  A review of variable selection methods in Partial Least Squares Regression , 2012 .

[24]  I. M. Scotford,et al.  Combination of Spectral Reflectance and Ultrasonic Sensing to monitor the Growth of Winter Wheat , 2004 .

[25]  J. A. Thomasson,et al.  Ground-Based Sensing System for Cotton Nitrogen Status Determination , 2006 .

[26]  Carly Golodets,et al.  Quantitative vs qualitative vegetation sampling methods: a lesson from a grazing experiment in a Mediterranean grassland , 2013 .

[27]  Leonard M. Lauriault,et al.  Irrigation and Nitrogen Treatments Slightly Affected Teff Yield and Quality in the Southwestern USA , 2013 .

[28]  S. Filin,et al.  Three-dimensional image-based modelling of linear features for plant biomass estimation , 2013 .

[29]  C. Rotz,et al.  Estimating Forage Mass with a Commercial Capacitance Meter, Rising Plate Meter, and Pasture Ruler , 2001 .

[30]  S. Wold,et al.  PLS: Partial Least Squares Projections to Latent Structures , 1993 .

[31]  D. Ehlert,et al.  Measuring crop biomass density by laser triangulation , 2008 .

[32]  William R. Raun,et al.  By‐Plant Prediction of Corn Forage Biomass and Nitrogen Uptake at Various Growth Stages Using Remote Sensing and Plant Height , 2007 .

[33]  D. Ehlert,et al.  Suitability of a laser rangefinder to characterize winter wheat , 2010, Precision Agriculture.

[34]  M. Wachendorf,et al.  Combining ultrasonic sward height and spectral signatures to assess the biomass of legume-grass swards , 2013 .

[35]  Jude Liu,et al.  Evaluation of two forage harvesting systems for herbaceous biomass harvesting , 2009 .

[36]  Q. Zaman,et al.  EFFECTS OF FOLIAGE DENSITY AND GROUND SPEED ON ULTRASONIC MEASUREMENT OF CITRUS TREE VOLUME , 2004 .

[37]  Pengfei Chen,et al.  A New Method for Winter Wheat Critical Nitrogen Curve Determination , 2013 .

[38]  D. Ehlert,et al.  Testing a vehicle-based scanning lidar sensor for crop detection , 2010 .

[39]  J. S. Schepers,et al.  Comparison of Ground‐Based Remote Sensors for Evaluation of Corn Biomass Affected by Nitrogen Stress , 2007 .

[40]  M. Wachendorf,et al.  Assessment of forage mass from grassland swards by height measurement using an ultrasonic sensor , 2011 .

[41]  N. Hutchings,et al.  An ultrasonic rangefinder for measuring the undisturbed surface height of continuously grazed grass swards , 1990 .