Differentiating forest types using TerraSAR–X spotlight images based on inferential statistics and multivariate analysis

Research output: Journal contributionsJournal articlesResearchpeer-review

Authors

This study investigated the potential of applying statistical analysis tests, for example, two sample Z-test and the Factor Analysis (FA) tool, on the TerraSAR-X backscattering coefficient, for distinguishing between different types of forests and detecting changes in distribution and extent of them. Two sample Z-test is an inferential statistical test that determines whether there is a statistically significant difference between the means in the data from two independent groups. FA is a multivariate analysis that can examine the structure or relationship between variables. Twelve pilot plots for forests of 17 ha were surveyed in a water protection catchment near Hanover, Germany. The forest types were deciduous, coniferous, and mixed. In order to sustain groundwater quality, deciduous trees were planted over a period of several years to gradually replace the coniferous trees in the catchment area. Regular forest observations were required to ensure that the percentages of deciduous and mixed forests in this catchment area were increasing relative to coniferous forests. Fourteen dual-co-polarized TerraSAR-X (HH/VV) images were used to monitor the forests in the period from March 2008 to January 2009. The values of the backscattering coefficient (σ0) for the test plots were statistically analyzed using the two sample Z-test and the Factor Analysis tools. The study showed that Factor analysis tools succeeded in differentiating between the coniferous forest and both the deciduous forest and the mixed forest, but failed to discriminate between the deciduous and the mixed forest. Only one factor was extracted for each sample plot of the coniferous forest with approximately equal loadings during the whole acquisition period from March 2008 to January 2009. However, two factors were extracted for each deciduous or mixed forest sample plot, where one factor had high loadings during the leaf-on period from May to October, and the other one had high loadings during the leaf-off period from November to April. Furthermore, the research revealed that the two sample Z-test differentiated the deciduous and mixed forests from the coniferous forest, and discriminated between deciduous forest and mixed forest. Statistically significant differences were observed between the mean backscatter values of the HH-polarized acquisitions for the deciduous forest and the mixed forest during the leaf-off period from November to April, but no statistically significant difference was found during the leaf-on period from May to October. Moreover, plot samples for the deciduous forest had slightly higher mean backscattering coefficients than those for the mixed forest during the leaf-off period. Applying the Factor Analysis and the two sample Z-test on the backscattering coefficient of multi-temporal TerraSAR-X data facilitates distinction of forest types, tracks changes in forest patterns, and estimates the extent of environmental disasters in forest regions. This accomplishes sustainable forest management, which can play an important role not only in preserving groundwater quality but also in achieving climate change adaptation goals.

Original languageEnglish
Article number100238
JournalRemote Sensing Applications: Society and Environment
Volume15
ISSN2352-9385
DOIs
Publication statusPublished - 01.08.2019

    Research areas

  • Coniferous forests, Deciduous forests, Factor analysis, Forest, Groundwater, SAR, TerraSAR-X, Z-Test
  • Ecosystems Research

Recently viewed

Publications

  1. Grounds different from, though equally solid with
  2. On the Appropriate Methodologies for Data Science Projects
  3. An innovative efficiency of incubator to enhance organization supportive business using machine learning approach
  4. Complexity and Administrative Intensity
  5. Knowledge integration
  6. Enhanced Calculation Procedures for Material and Energy Flow Oriented EMIS
  7. Modellieren in der Sekundarstufe
  8. Unveiling local knowledge
  9. Master of Disaster: A Disaster-Related Event Monitoring System From News Streams
  10. Understanding the error-structure of Time-driven Activity-based Costing
  11. A luenberger observer for a quasi-static disturbance estimation in linear time invariant systems
  12. Automated scoring in the era of artificial intelligence
  13. Integration durch soziale Kontrolle?
  14. Intraindividual variability in identity centrality
  15. Geometric structures using model predictive control for an electromagnetic actuator
  16. Relationships between language-related variations in text tasks, reading comprehension, and students’ motivation and emotions: A systematic review
  17. Petri net based EMIS-mappers for flexible manufacturing systems
  18. Guest Editors' Introduction
  19. Finite element modeling of laser beam welding for residual stress calculation
  20. Introduction to ‘Exploring the frontiers: unveiling new horizons in carbon efficient biomass utilization’
  21. Media coverage of discourse on adaptation
  22. Reliability and Validity of Assessing User Satisfaction With Web-Based Health Interventions
  23. Developing a Complex Portrait of Content Teaching for Multilingual Learners via Nonlinear Theoretical Understandings
  24. Challenges for postdocs in Germany and beyond:
  25. Supporting Visual and Verbal Learning Preferences in a Second-Language Multimedia Learning Environment
  26. Writing as a Deeper Form of Concentration
  27. Multilingual disambiguation of named entities using linked data
  28. A data-driven methodological routine to identify key indicators for social-ecological system archetype mapping
  29. Portuguese part-of-speech tagging with large margin structure learning