Hiperspektral Vejetasyon İndeksleri Kullanarak Otlaklarda Kanopi Düzeyinde Klorofil İçeriğinin Tahmin Edilmesi
Yıl 2021,
Sayı: 43, 77 - 91, 06.01.2022
Ahmet Karakoç
,
Murat Karabulut
Öz
Bu çalışma, farklı ekolojik koşullara sahip otlaklarda, kanopi düzeyinde klorofil içeriğini hiperspektral vejetasyon indeksleri kullanarak tahmin etmeyi hedeflemiştir. Bunun için ~500 m, ~1200 m ve ~1400 m olmak üzere üç farklı yükseltiye sahip otlak sahada, vejetasyonundaki klorofil içeriği verileri ile spektral verileri kanopi düzeyinde toplanmıştır. Bu işlemler 50X50 cm’lik kuadratlar içerisinde ve 213 farklı noktada gerçekleştirilmiştir. Veri toplama metodu olarak amaçlı örneklem ve transekt yöntemleri tercih edilmiştir. Toplanan veriler önce elde edildikleri yükselti basamağına göre (saha-temelli) daha sonra da içerdiği klorofil miktarına göre (miktar-temelli) iki kategoriye ayrılmış ve değerlendirmeler bu kategoriler üzerinden yapılmıştır. Analizler için önce spektral eğriler yorumlanmış, daha sonra da bu verilerden hiperspektral vejetasyon indeksleri üretilmiştir. Vejetasyon indekslerinin klorofil içeriğindeki varyasyonları açıklama gücünü modellemek için ise doğrusal, üstel, logaritmik ve üs fonksiyon modelleri kullanarak regresyon analizleri yapılmıştır. Bulgular; tüm verilerin değerlendirildiği heterojen veri setinde %85’in üzerinde, çalışma sahasının yükseltisinde göre yapılan analizlerde (saha-temelli) ise %90’ın üzerinde bir açıklama gücüne ulaşıldığını göstermiştir. Bu sahalarda, vejetasyondaki klorofil miktarı arttıkça modellerin gücünün belirgin bir şekilde azaldığı da ortaya konulmuştur. Bir başka dikkat çekici bulgu farklı çalışma alanlarından toplanarak benzer klorofil içeriklerine sahip örneklemler kullanılarak oluşturulan veri tabanında (miktar-temelli) açıklama gücünün belirgin bir biçimde düşmesi olmuştur.
Destekleyen Kurum
Kahramanmaraş Sütçü İmam Üniversitesi Bilimsel Araştırma Projeleri (BAP) Koordinasyon Birimi
Proje Numarası
2017-1-73D
Teşekkür
Arazi çalışmalarındaki destekleri için Gökay GÖKSU, İlhami DOĞAN, Sercan BAHÇECİ ve Ahmet AVCU’ ye teşekkürlerimizi sunarız.
Kaynakça
- Blackburn, G. A. (1998). Quantifying chlorophylls and caroteniods at leaf and canopy scales: An evaluation of some hyperspectral approaches. Remote Sensing of Environment, 66(3), 273-285. https://doi.org/10.1016/S0034-4257(98)00059-5. google scholar
- Buschman, C., & Nagel, E. (1993). In vivo spectroscopy and internal optics of leaves as a basis for remote sensing of vegetation. International Journal of Remote Sensing, 14, 711-
722. https://doi. org/10.1080/01431169308904370 google scholar
- Büyüköztürk, Ş. (2004). Sosyal bilimler için veri analizi el kitabı (4. bs). Ankara: PegemA Yayınları. google scholar
- Carter, G. A., & Knapp, A. K. (2001). Leaf optical properties in higher plants: Linking spectral characteristics to stress and chlorophyll concentration. American Journal ofBotany,
88(4), 677-684. https:// doi.org/10.2307/2657068 google scholar
- Chai, T., & Draxler, R. R. (2014). Root mean square error (RMSE) or mean absolute error (mae)? - Arguments against avoiding RMSE in the literature. Geoscientific Model
Development, 7(3), 1247-1250. https://doi.org/10.5194/gmd-7-1247-2014 google scholar
- Chang-Hua, J. U., Tian, Y., Yao, X., Cao, W., Zhu, Y., & Hannaway, D. (2010). Estimating leaf chlorophyll content using red edge parameters. Pedosphere, 20(5), 633-644.
https://doi.org/10.1016/ S1002-0160(10)60053-7 google scholar
- Chen, J. C., Yang, M., & Wu, S. T. (2007). Leaf chlorophyll content and surface spectral reflectance of tree species along a terrain gradient in Taiwan’s Kenting National Park. Bot
Stud, 48, 71-77. Erişim adresi: https://ejournal.sinica.edu.tw/ google scholar
- Curran, P. J., Dungan, J. L., & Gholz, H. L. (1990). Exploring the relationship between reflectance red edge and chlorophyll content in slash pine. Tree Physiology, 7(1-2-3-4), 33-48.
https://doi. org/10.1093/treephys/15.3.203 google scholar
- Çokluk, Ö., Şekercioğlu, G., & Büyüköztürk, Ş. (2012). Sosyal bilimler için çok değişkenli istatistik: SPSS ve Lisrel uygulamaları. Ankara: Pegem Akademi. google scholar
- Darvishzadeh, R. (2008). Hyperspectral remote sensing of vegetation parameters using statistical and physical models. (Doctoral dissertation, International Institute for Geo-
information Science and Earth Observation (ITC), the Netherlands). Retrieved from https:// research.utwente.nl/en/organisations/faculty-of-geo-information-science-and-
earth-observation google scholar
- Dash, J., & Curran, P. J. (2004). The MERIS terrestrial chlorophyll index. Int. J. Remote Sens., 25(23), 5403-5413. https://doi. org/10.1080/0143116042000274015 google scholar
- Datt, B. (1999). Visible/near infrared reflectance and chlorophyll content in eucalyptus leaves. International Journal of Remote Sensing. 20(14), 2741-2759.
https://doi.org/10.1080/014311699211778 google scholar
- Demir, E., Saatçioğlu, Ö. ve İmrol, F. (2016). Uluslararası dergilerde yayımlanan eğitim araştırmalarının normallik varsayımları açısından incelenmesi. Current Research in
Education, 2(3), 130-148. google scholar
- Genceli, M. (2007). Tek değişkenli dağılımlar ıçin Kolmogrov-Smirnov, Lilliefors ve Shapiro-Wilk normallik testleri. Sigma Mühendislik ve Fen Bilimleri Dergisi, 25(4), 306-328.
google scholar
- Geng, X. (2013). Modeling cool-season turfgrass lawn growth and quality responses to soil nitrogen and carbon, and tissue nitrogen concentrations. (Doctoral dissertation,
University of Connecticut, USA). Retrieved from https://opencommons.uconn.edu/ dissertations/272/?utm_source=opencommons.uconn. edu%2Fdissertations%2F272&utm
medium=PDF&utm _ _campaign=PDFCoverPages google scholar
- Gitelson, A. A., Gritz, Y., & Merzlyak, M. N. (2003). Relationships between leaf chlorophyll content and spectral reflectance and algorithms for non-destructive chlorophyll
assessment in higher plant leaves. Journal of Plant Physiology, 160, 271-282. https://doi. org/10.1078/0176-1617-00887 google scholar
- Göksu, G., Karabulut, & M., Karakoç., A. (2015, Mayıs). Türkiye’de bitki örtüsünün SPOT VEGETATION verileri ile incelenmesi. Coğrafyacılar Derneği Uluslararası Kongresi’nde sunulan
bildiri, Ankara Üniversitesi, Ankara. google scholar
- He, Y., & Mui, A. (2010). Scaling up semi-arid grassland biochemical content from the leaf to the canopy level: Challenges and opportunities. Sensors, 10, 11072-11087.
https://doi.org/10.3390/s101211072 google scholar
- He, Y. (2008). Modeling grassland productivity through remote sensing products. (Doctoral dissertation, University of Saskatchewan, Saskatoon, Canada). Retrieved from
https://harvest.usask.ca/ handle/10388/etd-03272008-112659 google scholar
- He, Y., Guo, X., & Wilmshurst, J. F. (2009). Reflectance measures of grassland biophysical structure. International Journal of Remote Sensing, 30(10), 2509-2521.
https://doi.org/10.1080/01431160802552751 google scholar
- Jiang Z., Huete, A., Li., J, & Chen, Y. (2006). An analysis of angle-based with ratio-based vegetation indices. IEEE Transactions on Geoscience and Remote Sensing, 44(9), 2506-
2513. doi: 10.1109/ TGRS.2006.873205 google scholar
- Jin, Y., Yang, X., Qiu, J., Li, J., Gao, T., Wu, Q., Zhao, F., Ma, H., Yu, H., & Xu, B., (2014). Remote sensing-based biomass estimation and its spatio-temporal variations in temperate
grassland, Northern China. Remote Sensing, 6, 1496-1513. https://doi.org/10.3390/ rs6021496 google scholar
- Karabulut, M., 2006. NOAA AVHRR verilerini kullanarak Türkiye’de bitki örtüsünün izlenmesi ve incelenmesi. Coğrafi Bilimler Dergisi, 4(1), 29-42. google scholar
- Karabulut, M. (2014). Vejetasyon coğrafyası araştırma yöntemleri. Y. Arı, I. Kaya (Ed.), Coğrafyada araştırma yöntemleri kitabı içinde (s. 355-365). Balıkesir: Coğrafyacılar Derneği
Yayınları. google scholar
- Karabulut, M. (2018). An examination of spectral reflectance properties of some wetland plants in Göksu Delta, Turkey. Journal of International Environmental Application and
Science, 13(4), 194203. google scholar
- Karabulut, M., (2019). Vejetasyon çalışmalarında uzaktan algılama. D.D. Yavaşlı, K. Ölgen (Ed.), Coğrafyada uzaktan algılama kitabı içinde (s. 109-160). İstanbul: Kriter Yayınları.
google scholar
- Karakoç, A. (2019). Otlaklardaki biyofiziksel ve biyokimyasal özelliklerin hiperspektral uzaktan algılama verileri ile incelenmesi, (Doktora Tezi). Kahramanmaraş Sütçü İmam
Üniversitesi Sosyal Bilimler Enstitüsü, Kahramanmaraş. google scholar
- Kim, H. Y. (2013). Statistical notes for clinical researchers: Assessing normal distribution (2) using skewness and kurtosis. Restorative Dentistry & Endodontics, 38(1), 52-54.
http://doi.org/10.5395/ rde.2013.38.1.52 google scholar
- Lillesand, T. M., Keifer, R. W., & Chipman, J. W. (2018). Uzaktan algılama ve görüntü yorumlama. (K.Ş Kavak, Çev.). Ankara: Palme Yayınevi. google scholar
- Li, Z., Xu, D., & Guo, X. (2014). Remote sensing of ecosystem health: Opportunities, challenges, and future perspectives. Sensors, 14, 21117-21139. doi:10.3390/s141121117 google scholar
- Ma, B. L., Morrison, M. J., & Dwyer, L. M. (1996). Canopy light reflectance and field greenness to assess nitrogen fertilization and yield of maize. Agronomy Journal, 88(6), 915-920. https://doi. org/10.2134/agronj1996.00021962003600060011x google scholar
- Mangiafico, S. S., & Guillard, K. (2005). Turfgrass reflectance measurements, chlorophyll, and soil nitrate desorbed from anion exchange membranes. Crop Sci., 45, 259-265.
https://doi. org/10.2135/cropsci2005.0259 google scholar
- Mcgrew, J. C., Lembo, A. J., & Monroe, C. B. (2014). An introduction to statistical problem solving in geography. 3rd ed. Long Grove, IL: Waveland Press. google scholar
- Peddle, D. R., White, H. P., Soffer, R. J., Miller, J. R., & Ledrew, E. F. (2001). Reflectance processing of remote sensing spectroradiometer data. Computer & Geoscience, 27, 203-213.
https://doi.org/10.1016/ S0098-3004(00)00096-0 google scholar
- Sims, D. A., & Gamon, J. A. (2002). Relationships between leaf pigment content and spectral reflectance across a wide range of species, leaf structures and developmental
stages. Remote Sens. Environ., 81, 337-354. https://doi.org/10.1016/S0034-4257(02)00010-X google scholar
- Tong, A., & He, Y. (2014, July). Remote sensing of grassland chlorophyll content: assessing the spatial-temporal performance of spectral indices. IEEE International Geoscience
and Remote Sensing Symposium, Quebec City, Quebec, Canada. Erişim adresi: https:// ieeexplore.ieee.org/document/6947069 google scholar
- Varol, Ö. (2003). Flora of Başkonuş Mountain (Kahramanmaraş). Turkish Journal of Botany, 27(2), 117-139. google scholar
- Wong, K. K., & He, Y. (2013). Estimating grassland chlorophyll content using remote sensing data at leaf, canopy, and landscape scales. Canadian Journal of Remote Sensing, 3,
155-166. https://doi. org/10.5589/m13-021 google scholar
- Wu, C., Niu, Z., Tang, Q., & Huang, W. (2008). Estimating chlorophyll content from hyperspectral vegetation indices: Modeling and validation. Agricultural and Forest Meteorology,
148(8), 12301241. https://doi.org/10.1016/j.agrformet.2008.03.005 google scholar
- Xue, L., Cao, W., Luo, W., Dai, T., & Zhu, Y. (2004). Monitoring leaf nitrogen status in rice with canopy spectral reflectance, Agron. J., 96(1), 135-142.
https://doi.org/10.2134/agronj2004.1350 google scholar
- Yin, C., He, B., Quan, X., & Liao, Z. (2016). Chlorophyll content estimation in arid grasslands from Landsat-8 OLI data. International Journal of Remote Sensing, 37(3), 615-632.
https://doi.org/10.1080 /01431161.2015.1131867 google scholar
- Zarco-Tejada, P. J., Miller, J. R., Noland, T. L., Mohammed, G. H., & Sampson, P. H. (2001). Scaling-up and model inversion methods with narrowband optical indices for chlorophyll
content estimation in closed forest canopies with hyperspectral data. IEEE T. Geosci. Remote, 39(7), 1491-1507. doi: 10.1109/36.934080. google scholar
- Zhao, F., Xu, B., Yang, X., Jin, Y., Li, J., Xia, L., ..., & Ma, H. (2014). Remote sensing estimates of grassland aboveground biomass based on MODIS net primary productivity (NPP): A
case study in the Xilingol Grassland of Northern China. Remote sensing, 6(6), 53685386. https://doi.org/10.3390/rs6065368 google scholar
Estimating Grassland Chlorophyll Content at Canopy Scales Using Hyperspectral Vegetation Indices
Yıl 2021,
Sayı: 43, 77 - 91, 06.01.2022
Ahmet Karakoç
,
Murat Karabulut
Öz
This study aims to estimate the chlorophyll content at the canopy level using the hyperspectral vegetation indices in grasslands with different ecological conditions. For this purpose, all data were collected from three different elevation steps of ~500 m, ~1200 m, and ~ 1400 m. The operations were performed in 50 × 50 cm quadrates at 213 different locations at the canopy level. Purposeful sampling and transect methods were preferred as the data collection methods. The database was divided into two categories according to the elevation step they were collected (field-based) and the amount of chlorophyll content (quantity-based). Assessments were then made in these two categories and their classes. In the analyses, the spectral curves were interpreted, and the hyperspectral vegetation indices were calculated from the aforementioned databases. Regression analyses were used to model the performances of the vegetation indices and explain the chlorophyll content variations. For this, linear, exponential, logarithmic, and power function models were employed. The results show an explanation power of over 85% in the data set containing all the data and over 90% in the field-based data set. In contrast, the power of the models significantly decreased as the chlorophyll content increased.
Proje Numarası
2017-1-73D
Kaynakça
- Blackburn, G. A. (1998). Quantifying chlorophylls and caroteniods at leaf and canopy scales: An evaluation of some hyperspectral approaches. Remote Sensing of Environment, 66(3), 273-285. https://doi.org/10.1016/S0034-4257(98)00059-5. google scholar
- Buschman, C., & Nagel, E. (1993). In vivo spectroscopy and internal optics of leaves as a basis for remote sensing of vegetation. International Journal of Remote Sensing, 14, 711-
722. https://doi. org/10.1080/01431169308904370 google scholar
- Büyüköztürk, Ş. (2004). Sosyal bilimler için veri analizi el kitabı (4. bs). Ankara: PegemA Yayınları. google scholar
- Carter, G. A., & Knapp, A. K. (2001). Leaf optical properties in higher plants: Linking spectral characteristics to stress and chlorophyll concentration. American Journal ofBotany,
88(4), 677-684. https:// doi.org/10.2307/2657068 google scholar
- Chai, T., & Draxler, R. R. (2014). Root mean square error (RMSE) or mean absolute error (mae)? - Arguments against avoiding RMSE in the literature. Geoscientific Model
Development, 7(3), 1247-1250. https://doi.org/10.5194/gmd-7-1247-2014 google scholar
- Chang-Hua, J. U., Tian, Y., Yao, X., Cao, W., Zhu, Y., & Hannaway, D. (2010). Estimating leaf chlorophyll content using red edge parameters. Pedosphere, 20(5), 633-644.
https://doi.org/10.1016/ S1002-0160(10)60053-7 google scholar
- Chen, J. C., Yang, M., & Wu, S. T. (2007). Leaf chlorophyll content and surface spectral reflectance of tree species along a terrain gradient in Taiwan’s Kenting National Park. Bot
Stud, 48, 71-77. Erişim adresi: https://ejournal.sinica.edu.tw/ google scholar
- Curran, P. J., Dungan, J. L., & Gholz, H. L. (1990). Exploring the relationship between reflectance red edge and chlorophyll content in slash pine. Tree Physiology, 7(1-2-3-4), 33-48.
https://doi. org/10.1093/treephys/15.3.203 google scholar
- Çokluk, Ö., Şekercioğlu, G., & Büyüköztürk, Ş. (2012). Sosyal bilimler için çok değişkenli istatistik: SPSS ve Lisrel uygulamaları. Ankara: Pegem Akademi. google scholar
- Darvishzadeh, R. (2008). Hyperspectral remote sensing of vegetation parameters using statistical and physical models. (Doctoral dissertation, International Institute for Geo-
information Science and Earth Observation (ITC), the Netherlands). Retrieved from https:// research.utwente.nl/en/organisations/faculty-of-geo-information-science-and-
earth-observation google scholar
- Dash, J., & Curran, P. J. (2004). The MERIS terrestrial chlorophyll index. Int. J. Remote Sens., 25(23), 5403-5413. https://doi. org/10.1080/0143116042000274015 google scholar
- Datt, B. (1999). Visible/near infrared reflectance and chlorophyll content in eucalyptus leaves. International Journal of Remote Sensing. 20(14), 2741-2759.
https://doi.org/10.1080/014311699211778 google scholar
- Demir, E., Saatçioğlu, Ö. ve İmrol, F. (2016). Uluslararası dergilerde yayımlanan eğitim araştırmalarının normallik varsayımları açısından incelenmesi. Current Research in
Education, 2(3), 130-148. google scholar
- Genceli, M. (2007). Tek değişkenli dağılımlar ıçin Kolmogrov-Smirnov, Lilliefors ve Shapiro-Wilk normallik testleri. Sigma Mühendislik ve Fen Bilimleri Dergisi, 25(4), 306-328.
google scholar
- Geng, X. (2013). Modeling cool-season turfgrass lawn growth and quality responses to soil nitrogen and carbon, and tissue nitrogen concentrations. (Doctoral dissertation,
University of Connecticut, USA). Retrieved from https://opencommons.uconn.edu/ dissertations/272/?utm_source=opencommons.uconn. edu%2Fdissertations%2F272&utm
medium=PDF&utm _ _campaign=PDFCoverPages google scholar
- Gitelson, A. A., Gritz, Y., & Merzlyak, M. N. (2003). Relationships between leaf chlorophyll content and spectral reflectance and algorithms for non-destructive chlorophyll
assessment in higher plant leaves. Journal of Plant Physiology, 160, 271-282. https://doi. org/10.1078/0176-1617-00887 google scholar
- Göksu, G., Karabulut, & M., Karakoç., A. (2015, Mayıs). Türkiye’de bitki örtüsünün SPOT VEGETATION verileri ile incelenmesi. Coğrafyacılar Derneği Uluslararası Kongresi’nde sunulan
bildiri, Ankara Üniversitesi, Ankara. google scholar
- He, Y., & Mui, A. (2010). Scaling up semi-arid grassland biochemical content from the leaf to the canopy level: Challenges and opportunities. Sensors, 10, 11072-11087.
https://doi.org/10.3390/s101211072 google scholar
- He, Y. (2008). Modeling grassland productivity through remote sensing products. (Doctoral dissertation, University of Saskatchewan, Saskatoon, Canada). Retrieved from
https://harvest.usask.ca/ handle/10388/etd-03272008-112659 google scholar
- He, Y., Guo, X., & Wilmshurst, J. F. (2009). Reflectance measures of grassland biophysical structure. International Journal of Remote Sensing, 30(10), 2509-2521.
https://doi.org/10.1080/01431160802552751 google scholar
- Jiang Z., Huete, A., Li., J, & Chen, Y. (2006). An analysis of angle-based with ratio-based vegetation indices. IEEE Transactions on Geoscience and Remote Sensing, 44(9), 2506-
2513. doi: 10.1109/ TGRS.2006.873205 google scholar
- Jin, Y., Yang, X., Qiu, J., Li, J., Gao, T., Wu, Q., Zhao, F., Ma, H., Yu, H., & Xu, B., (2014). Remote sensing-based biomass estimation and its spatio-temporal variations in temperate
grassland, Northern China. Remote Sensing, 6, 1496-1513. https://doi.org/10.3390/ rs6021496 google scholar
- Karabulut, M., 2006. NOAA AVHRR verilerini kullanarak Türkiye’de bitki örtüsünün izlenmesi ve incelenmesi. Coğrafi Bilimler Dergisi, 4(1), 29-42. google scholar
- Karabulut, M. (2014). Vejetasyon coğrafyası araştırma yöntemleri. Y. Arı, I. Kaya (Ed.), Coğrafyada araştırma yöntemleri kitabı içinde (s. 355-365). Balıkesir: Coğrafyacılar Derneği
Yayınları. google scholar
- Karabulut, M. (2018). An examination of spectral reflectance properties of some wetland plants in Göksu Delta, Turkey. Journal of International Environmental Application and
Science, 13(4), 194203. google scholar
- Karabulut, M., (2019). Vejetasyon çalışmalarında uzaktan algılama. D.D. Yavaşlı, K. Ölgen (Ed.), Coğrafyada uzaktan algılama kitabı içinde (s. 109-160). İstanbul: Kriter Yayınları.
google scholar
- Karakoç, A. (2019). Otlaklardaki biyofiziksel ve biyokimyasal özelliklerin hiperspektral uzaktan algılama verileri ile incelenmesi, (Doktora Tezi). Kahramanmaraş Sütçü İmam
Üniversitesi Sosyal Bilimler Enstitüsü, Kahramanmaraş. google scholar
- Kim, H. Y. (2013). Statistical notes for clinical researchers: Assessing normal distribution (2) using skewness and kurtosis. Restorative Dentistry & Endodontics, 38(1), 52-54.
http://doi.org/10.5395/ rde.2013.38.1.52 google scholar
- Lillesand, T. M., Keifer, R. W., & Chipman, J. W. (2018). Uzaktan algılama ve görüntü yorumlama. (K.Ş Kavak, Çev.). Ankara: Palme Yayınevi. google scholar
- Li, Z., Xu, D., & Guo, X. (2014). Remote sensing of ecosystem health: Opportunities, challenges, and future perspectives. Sensors, 14, 21117-21139. doi:10.3390/s141121117 google scholar
- Ma, B. L., Morrison, M. J., & Dwyer, L. M. (1996). Canopy light reflectance and field greenness to assess nitrogen fertilization and yield of maize. Agronomy Journal, 88(6), 915-920. https://doi. org/10.2134/agronj1996.00021962003600060011x google scholar
- Mangiafico, S. S., & Guillard, K. (2005). Turfgrass reflectance measurements, chlorophyll, and soil nitrate desorbed from anion exchange membranes. Crop Sci., 45, 259-265.
https://doi. org/10.2135/cropsci2005.0259 google scholar
- Mcgrew, J. C., Lembo, A. J., & Monroe, C. B. (2014). An introduction to statistical problem solving in geography. 3rd ed. Long Grove, IL: Waveland Press. google scholar
- Peddle, D. R., White, H. P., Soffer, R. J., Miller, J. R., & Ledrew, E. F. (2001). Reflectance processing of remote sensing spectroradiometer data. Computer & Geoscience, 27, 203-213.
https://doi.org/10.1016/ S0098-3004(00)00096-0 google scholar
- Sims, D. A., & Gamon, J. A. (2002). Relationships between leaf pigment content and spectral reflectance across a wide range of species, leaf structures and developmental
stages. Remote Sens. Environ., 81, 337-354. https://doi.org/10.1016/S0034-4257(02)00010-X google scholar
- Tong, A., & He, Y. (2014, July). Remote sensing of grassland chlorophyll content: assessing the spatial-temporal performance of spectral indices. IEEE International Geoscience
and Remote Sensing Symposium, Quebec City, Quebec, Canada. Erişim adresi: https:// ieeexplore.ieee.org/document/6947069 google scholar
- Varol, Ö. (2003). Flora of Başkonuş Mountain (Kahramanmaraş). Turkish Journal of Botany, 27(2), 117-139. google scholar
- Wong, K. K., & He, Y. (2013). Estimating grassland chlorophyll content using remote sensing data at leaf, canopy, and landscape scales. Canadian Journal of Remote Sensing, 3,
155-166. https://doi. org/10.5589/m13-021 google scholar
- Wu, C., Niu, Z., Tang, Q., & Huang, W. (2008). Estimating chlorophyll content from hyperspectral vegetation indices: Modeling and validation. Agricultural and Forest Meteorology,
148(8), 12301241. https://doi.org/10.1016/j.agrformet.2008.03.005 google scholar
- Xue, L., Cao, W., Luo, W., Dai, T., & Zhu, Y. (2004). Monitoring leaf nitrogen status in rice with canopy spectral reflectance, Agron. J., 96(1), 135-142.
https://doi.org/10.2134/agronj2004.1350 google scholar
- Yin, C., He, B., Quan, X., & Liao, Z. (2016). Chlorophyll content estimation in arid grasslands from Landsat-8 OLI data. International Journal of Remote Sensing, 37(3), 615-632.
https://doi.org/10.1080 /01431161.2015.1131867 google scholar
- Zarco-Tejada, P. J., Miller, J. R., Noland, T. L., Mohammed, G. H., & Sampson, P. H. (2001). Scaling-up and model inversion methods with narrowband optical indices for chlorophyll
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