Wachendorf, Michael

[["dc.bibliographiccitation.firstpage","265"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Photogrammetrie - Fernerkundung - Geoinformation"],["dc.bibliographiccitation.lastpage","275"],["dc.contributor.author","Mewes, Thorsten"],["dc.contributor.author","Erasmi, Stefan"],["dc.contributor.author","Kappas, Martin W."],["dc.contributor.author","Biewer, Sonja"],["dc.contributor.author","Fricke, Thomas"],["dc.contributor.author","Wachendorf, Michael"],["dc.date.accessioned","2018-11-07T11:20:35Z"],["dc.date.available","2018-11-07T11:20:35Z"],["dc.date.issued","2008"],["dc.description.abstract","This paper focuses on the detection of individual fractions of legume and grass species based on Spectral Mixture Analysis of remotely sensed. non-imaging data. In 005 one glasshouse-experiment and one field-experiment were built up and continuous measurements and samples were taken for subsequent comparison. Marked crop-plots were spectrally recorded with the fieldspectrometer ASD Fieldspec (c) Pro JR and subsequently harvested for laboratory analysis. In the first step the reflection signatures were smoothed by the adaptive Savitzky-Golay-Filter and evaluated for inaccurate data by means of descriptive statistics. After reduction to relevant wavelength-ranges the spectra were unmixed to their pure components (endmembers). One of the basic steps here is the selection of accurate endmembers. The endmembers have to represent one fraction in an appropriate manner. The results show the possibilities and limits of the method with fieldspectrometrical data with focus on their usage for site specific forage production. Good relations could be found for the data of the glasshouse-experiment, whereas the data from the field-experiment show deficiencies, mainly due to high weed rates and a more complex stand structure."],["dc.identifier.isi","000261058700003"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/55569"],["dc.language.iso","en"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.issn","1432-8364"],["dc.title","Spectral Mixture Analysis (SMA) of reflectance curves from Legume-Grass-Plots for the analysis of species composition in forage production."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","128"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Precision Agriculture"],["dc.bibliographiccitation.lastpage","144"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Biewer, Sonja"],["dc.contributor.author","Erasmi, Stefan"],["dc.contributor.author","Fricke, Thomas"],["dc.contributor.author","Wachendorf, Michael"],["dc.date.accessioned","2018-11-07T08:31:26Z"],["dc.date.accessioned","2020-05-11T13:30:32Z"],["dc.date.available","2018-11-07T08:31:26Z"],["dc.date.available","2020-05-11T13:30:32Z"],["dc.date.issued","2009"],["dc.description.abstract","Productivity and botanical composition of legume-grass swards in rotation systems are important factors for successful arable farming in both organic and conventional farming systems. As these attributes vary considerably within a field, a non-destructive method of detection while doing other tasks would facilitate more targeted management of crops and nutrients in the soil-plant-animal system. Two pot experiments were conducted to examine the potential of field spectroscopy to assess total biomass and the proportions of legume, using binary mixtures and pure swards of grass and legumes. The spectral reflectance of swards was measured under artificial light conditions at a sward age ranging from 21 to 70 days. Total biomass was determined by modified partial least squares (MPLS) regression, stepwise multiple linear regression (SMLR) and the vegetation indices (VIs) simple ratio (SR), normalized difference vegetation index (NDVI), enhanced vegetation index (EVI) and red edge position (REP). Modified partial least squares and SMLR gave the largest R (2) values ranging from 0.85 to 0.99. Total biomass prediction by VIs resulted in R (2) values of 0.87-0.90 for swards with large leaf to stem ratios; the greatest accuracy was for EVI. For more mature and open swards VI-based detection of biomass was not possible. The contribution of legumes to the sward could be determined at a constant biomass level by the VIs, but this was not possible when the level of biomass varied."],["dc.identifier.doi","10.1007/s11119-008-9078-9"],["dc.identifier.isi","000263685600003"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/65060"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.eissn","1573-1618"],["dc.relation.issn","1385-2256"],["dc.title","Prediction of yield and the contribution of legumes in legume-grass mixtures using field spectrometry"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dspace.entity.type","Publication"]]