Foraging ecology of three sympatric ungulate species – Behavioural and resource maps indicate differences between chamois, ibex and red deer

Movement Ecology

Anita C Risch¹  Rudolf Haller³  Mathias Kneubühler²  Michael E Schaepman²  Pia Anderwald³  Martin Schütz¹  Anna K Schweiger³ 

[1] Research Unit Community Ecology, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, Birmensdorf, 8903, Switzerland;Remote Sensing Laboratories, Department of Geography, University of Zurich, Winterthurerstrasse 190, Zürich, 8057, Switzerland;Department of Research and Geoinformation, Swiss National Park, Chastè Planta-Wildenberg, Zernez, 7530, Switzerland

关键词: Vegetation;    Utilisation distribution;    T-LoCoH;    Resource selection;    Remote sensing;    Nitrogen;    Movement;    Imaging spectroscopy;    Forage;    Biomass;   

Others  :  1171075
DOI  :  10.1186/s40462-015-0033-x

 received in 2014-11-04, accepted in 2015-02-23,  发布年份 2015

【 摘 要 】

Background

The spatial distribution of forage resources is a major driver of animal movement patterns. Understanding where animals forage is important for the conservation of multi-species communities, since interspecific competition can emerge if different species use the same depletable resources. However, determining forage resources in a spatially continuous fashion in alpine grasslands at high spatial resolution was challenging up to now, because terrain heterogeneity causes vegetation characteristics to vary at small spatial scales, and methods for detection of behavioural phases in animal movement patterns were not widely available. We delineated areas coupled to the foraging behaviour of three sympatric ungulate species (chamois, ibex, red deer) using Time Local Convex Hull (T-LoCoH), a non-parametric utilisation distribution method incorporating spatial and temporal autocorrelation structure of GPS data. We used resource maps of plant biomass and plant nitrogen content derived from high-resolution airborne imaging spectroscopy data, and multinomial logistic regression to compare the foraging areas of the three ungulate species.

Results

We found significant differences in plant biomass and plant nitrogen content between the core foraging areas of chamois, ibex and red deer. Core foraging areas of chamois were characterised by low plant biomass and low to medium plant nitrogen content. Core foraging areas of ibex were, in contrast, characterised by high plant nitrogen content, but varied in plant biomass, and core foraging areas of red deer had high plant biomass, but varied in plant nitrogen content.

Conclusions

Previous studies carried out in the same study area found no difference in forage consumed by chamois, ibex and red deer. Methodologically, those studies were based on micro-histological analysis of plant fragments identifying them to plant family or functional type level. However, vegetation properties such as productivity (biomass) or plant nutrient content can vary within vegetation communities, especially in highly heterogeneous landscapes. Thus, the combination of high spatial resolution resource maps with a utilisation distribution method allowing to generate behavioural maps (T-LoCoH) provides new insights into the foraging ecology of the three sympatric species, important for their conservation and to monitor expected future changes.

【 授权许可】

   
2015 Schweiger et al.; licensee BioMed Central.

【 图 表 】

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【 参考文献 】

• [1]Hutchinson GE. Homage to Santa Rosalia or why are there so many kinds of animals? American Naturalist 1959:145–159.
• [2]Van Langevelde F, Prins HHT. Introduction to Resource Ecology. In Resource Ecology. Edited by Prins HHT, Van Langevelde F. Springer Netherlands; 2008: 1–6
• [3]Hanley TA: A nutritional view of understanding and complexity in the problem of diet selection by deer (Cervidae). Oikos 1997, 79:209-218.
• [4]McNaughton SJ: Grazing as an Optimization Process: Grass-Ungulate Relationships in the Serengeti. Am Nat 1979, 113:691-703.
• [5]McNaughton SJ, Banyikwa FF, McNaughton MM: Promotion of the cycling of diet-enhancing nutrients by African grazers. Science 1997, 278:1798-1800.
• [6]Risch AC, Frank DA: Carbon dioxide fluxes in a spatially and temporally heterogeneous temperate grassland. Oecologia 2006, 147:291-302.
• [7]De Knegt HJ, Groen TA, Van De Vijver CADM, Prins HHT, Van Langevelde F: Herbivores as architects of savannas: Inducing and modifying spatial vegetation patterning. Oikos 2008, 117:543-554.
• [8]De Jager NR, Pastor J: Declines in moose population density at Isle Royle National Park, MI, USA and accompanied changes in landscape patterns. Landscape Ecol 2009, 24:1389-1403.
• [9]Coughenour MB: Spatial components of plant-herbivore interactions in pastoral, ranching, and native ungulate ecosystems. J Range Manage 1991, 44:530-542.
• [10]Wardle DA, Bardgett RD, Klironomos JN, Setälä H, Van Der Putten WH, Wall DH: Ecological linkages between aboveground and belowground biota. Science 2004, 304:1629-1633.
• [11]Bailey DW, Gross JE, Laca EA, Rittenhouse LR, Coughenour MB, Swift DM, et al.: Mechanisms that result in large herbivore grazing distribution patterns. J Range Manage 1996, 49:386-400.
• [12]Hofmann RR: Evolutionary Steps of Ecophysiological Adaptation and Diversification of Ruminants: A Comparative View of Their Digestive System. Oecologia 1989, 78:443-457.
• [13]Gordon IJ, Illius AW: Resource partitioning by ungulates on the Isle of Rhum. Oecologia 1989, 79:383-389.
• [14]Brambilla P, Bocci A, Ferrari C, Lovari S: Food patch distribution determines home range size of adult male chamois only in rich habitats. Ethology Ecology & Evolution 2006, 18:185-193.
• [15]Hülber K, Ertl S, Gottfried M, Reiter K, Grabherr G: Gourmets or gourmands?—Diet selection by large ungulates in high-alpine plant communities and possible impacts on plant propagation. Basic and Applied Ecology 2005, 6:1-10.
• [16]Bagchi S, Goyal SP, Sankar K: Habitat separation among ungulates in dry tropical forests of Ranthambhore national park Rajasthan. Tropical Ecology 2003, 44:175-181.
• [17]Bertolino S, Di Montezemolo NC, Bassano B: Food-niche relationships within a guild of alpine ungulates including an introduced species. Journal of Zoology 2009, 277:63-69.
• [18]La Morgia V, Bassano B: Feeding habits, forage selection, and diet overlap in Alpine chamois (Rupicapra rupicapra L.) and domestic sheep. Ecological Research 2009, 24:1043-1050.
• [19]Klansek E, Vavra I, Onderscheka K: Die Äsungszusammensetzung des Alpensteinwildes (Capra i. ibex L.) in Abhängigkeit von Jahreszeit, Alter und Äsungsangebot in Graubünden. Zeitschrift für Jagdwissenschaften 1995, 41:171-181.
• [20]Lovari S, Ferretti F, Corazza M, Minder I, Troiani N, Ferrari C, et al. Unexpected consequences of reintroductions: competition between increasing red deer and threatened Apennine chamois. Animal Conservation 2014.
• [21]Pérez-Barbería FJ, Gordon IJ, Nores C: Evolutionary transitions among feeding styles and habitats in ungulates. Evolutionary Ecology Research 2001, 3:221-230.
• [22]Zingg A. Seasonal variability in the diet composition of Alpine ibex (Capra ibex L.) in the Swiss National Park. University of Zurich, Institute of Evolutionary Biology and Environmental Studies; 2009.
• [23]Trutmann C. Diet composition of alpine chamois (Rupicapra rupicapra L.): Is there evidence for forage competition to the alpine ibex (Capra ibex L.)? University of Zurich, Institute of Evolutionary Biology and Environmental Studies; 2009.
• [24]Anderwald P, Haller R, Risch AC, Schütz M, Schweiger AK, Filli F. Resource competition between chamois, alpine ibex and red deer in the Swiss National Park? In 5th Symposium for Research in Protected Areas; Mittersill. 2013
• [25]Duparc A, Redjadj C, Viard-Crétat F, Lavorel S, Austrheim G, Loison A: Co-variation between plant above-ground biomass and phenology in sub-alpine grasslands. Applied Vegetation Science 2013, 16:305-316.
• [26]Blix AW, Mysterud A, Loe LE, Austrheim G: Temporal scales of density-dependent habitat selection in a large grazing herbivore. Oikos 2014, 123:933-942.
• [27]Kerr JT, Ostrovsky M: From space to species: Ecological applications for remote sensing. Trends in Ecology and Evolution 2003, 18:299-305.
• [28]Aplin P: Remote sensing: Ecology. Progress in Physical Geography 2005, 29:104-113.
• [29]Kneubühler M, Damm A, Schweiger A, Risch A, Schütz M, Schaepman M: Continuous Fields From Imaging Spectrometer Data for Ecosystem Parameter Mapping and Their Potential for Animal Habitat Assessment in Alpine Regions. IEEE J Selected Topics Appl Earth Observations Remote Sensing 2014, 7:2600-2610.
• [30]Schaepman ME, Ustin SL, Plaza AJ, Painter TH, Verrelst J, Liang S: Earth system science related imaging spectroscopy-An assessment. Remote Sensing of Environment 2009, 113:S123-S137.
• [31]Schaepman ME, Jehle M, Hueni A, D’Odorico P, Damm A, Weyermann J, et al.: Advanced radiometry measurements and Earth science applications with the Airborne Prism Experiment (APEX). Remote Sensing of Environment 2015, 158:207-219.
• [32]Ustin SL, Roberts DA, Gamon JA, Asner GP, Green RO: Using imaging spectroscopy to study ecosystem processes and properties. BioScience 2004, 54:523-534.
• [33]Wang K, Franklin SE, Guo X, Cattet M: Remote sensing of ecology, biodiversity and conservation: A review from the perspective of remote sensing specialists. Sensors 2010, 10:9647-9667.
• [34]Pottier J, Malenovský Z, Psomas A, Homolová L, Schaepman ME, Choler P, et al.: Modelling plant species distribution in alpine grasslands using airborne imaging spectroscopy. Biology letters 2014, 10:20140347.
• [35]Skidmore AK, Ferwerda JG, Mutanga O, Van Wieren SE, Peel M, Grant RC, et al.: Forage quality of savannas - Simultaneously mapping foliar protein and polyphenols for trees and grass using hyperspectral imagery. Remote Sensing of Environment 2010, 114:64-72.
• [36]McNaughton S: Mineral nutrition and spatial concentrations of African ungulates. Nature 1988, 334:343.
• [37]Langvatn R, Hanley TA: Feeding-patch choice by red deer in relation to foraging efficiency. Oecologia 1993, 95:164-170.
• [38]Wilmshurst JF, Fryxell JM: Patch selection by red deer in relation to energy and protein intake: a re-evaluation of Langvatn and Hanley’s (1993) results. Oecologia 1995, 104:297-300.
• [39]Smallegange IM, Brunsting AMH: Food supply and demand, a simulation model of the functional response of grazing ruminants. Ecological Modelling 2002, 149:179-192.
• [40]Cho MA, Skidmore AK: Hyperspectral predictors for monitoring biomass production in Mediterranean mountain grasslands: Majella National Park, Italy. International Journal of Remote Sensing 2009, 30:499-515.
• [41]Schweiger AK, Risch AC, Damm A, Kneubühler M, Haller R, Schaepman ME, et al.: Using imaging spectroscopy to predict above-ground plant biomass in alpine grasslands grazed by large ungulates. Journal of Vegetation Science 2015, 26:175-190.
• [42]Mutanga O, Skidmore AK: Integrating imaging spectroscopy and neural networks to map grass quality in the Kruger National Park, South Africa. Remote Sensing of Environment 2004, 90:104-115.
• [43]Burt WH: Territoriality and home range concepts as applied to mammals. Journal of Mammalogy 1943, 24:346-352.
• [44]Cagnacci F, Boitani L, Powell RA, Boyce MS: Animal ecology meets GPS-based radiotelemetry: a perfect storm of opportunities and challenges. Philosophical Transactions of the Royal Society B: Biological Sciences 2010, 365:2157-2162.
• [45]Tomkiewicz SM, Fuller MR, Kie JG, Bates KK: Global positioning system and associated technologies in animal behaviour and ecological research. Philosophical Transactions of the Royal Society B: Biological Sciences 2010, 365:2163-2176.
• [46]Burgman MA, Fox JC: Bias in species range estimates from minimum convex polygons: implications for conservation and options for improved planning. Animal Conservation 2003, 6:19-28.
• [47]Getz WM, Wilmers CC: A local nearest‐neighbor convex‐hull construction of home ranges and utilization distributions. Ecography 2004, 27:489-505.
• [48]Otis DL, White GC. Autocorrelation of location estimates and the analysis of radiotracking data. J Wildlife Manage. 1999:1039–1044.
• [49]McNay RS, Morgan JA, Bunnell FL. Characterizing independence of observations in movements of Columbian black-tailed deer. J Wildlife Manage. 1994:422–429.
• [50]Fieberg J, Matthiopoulos J, Hebblewhite M, Boyce MS, Frair JL: Correlation and studies of habitat selection: problem, red herring or opportunity? Philosophical Trans Royal Soc B Biol Sci 2010, 365:2233-2244.
• [51]Fieberg J: Kernel density estimators of home range: smoothing and the autocorrelation red herring. Ecology 2007, 88:1059-1066.
• [52]Solla D, Shane R, Bonduriansky R, Brooks RJ: Eliminating autocorrelation reduces biological relevance of home range estimates. J Anim Ecol 1999, 68:221-234.
• [53]Horne JS, Garton EO, Krone SM, Lewis JS: Analyzing animal movements using Brownian bridges. Ecology 2007, 88:2354-2363.
• [54]Kranstauber B, Kays R, LaPoint SD, Wikelski M, Safi K: A dynamic Brownian bridge movement model to estimate utilization distributions for heterogeneous animal movement. J An Ecol 2012, 81:738-746.
• [55]Viswanathan GM, Buldyrev SV, Havlin S, da Luz MGE, Raposo EP, Stanley HE: Optimizing the success of random searches. Nature 1999, 401:911-914.
• [56]Benhamou S, Riotte-Lambert L: Beyond the Utilization Distribution: Identifying home range areas that are intensively exploited or repeatedly visited. Ecological Modelling 2012, 227:112-116.
• [57]Wall J, Wittemyer G, LeMay V, Douglas‐Hamilton I, Klinkenberg B: Elliptical Time-Density model to estimate wildlife utilization distributions. Methods in Ecology and Evolution 2014, 5:780-790.
• [58]Long JA, Nelson TA: Time geography and wildlife home range delineation. The Journal of Wildlife Management 2012, 76:407-413.
• [59]Bartumeus F, Levin SA: Fractal reorientation clocks: Linking animal behavior to statistical patterns of search. Proceedings of the National Academy of Sciences 2008, 105:19072-19077.
• [60]Patterson TA, Thomas L, Wilcox C, Ovaskainen O, Matthiopoulos J: State–space models of individual animal movement. Trends in ecology & evolution 2008, 23:87-94.
• [61]Lyons AJ, Turner WC, Getz WM: Home range plus: A space-time characterization of movement over real landscapes. Movement Ecology 2013, 1:1-14. BioMed Central Full Text
• [62]Brown DR, Sherry TW: Solitary winter roosting of Ovenbirds in core foraging area. The Wilson Journal of Ornithology 2008, 120:455-459.
• [63]Bontadina F, Schofield H, Naef-Daenzer B: Radio-tracking reveals that lesser horseshoe bats (Rhinolophus hipposideros) forage in woodland. Journal of Zoology 2002, 258:281-290.
• [64][https://www.parcs.ch/mmds/pdf_public/3941_GB_SNP_2010.pdf] webcite Schweizerische Eidgenössische Nationalparkkommission (ENPK): Geschäftsbericht 2010–2013 [, https://www.parcs.ch/mmds/pdf_public/4282_GB_SNP_2011.pdf webcite, http://www.parcs.ch/snp/pdf_public/2013/9746_20130731_124944_Geschaeftsbericht_2012_DEF.pdf webcite, http://www.parcs.ch/snp/pdf_public/2014/30465_20141029_123957_Geschaeftsbericht_2013.pdf webcite]
• [65]Hudson R, Frank S. Foraging ecology of bison in aspen boreal habitats. Journal of Range Management 1987:71–75.
• [66]Hamel S, Côté SD: Trade-offs in activity budget in an alpine ungulate: contrasting lactating and nonlactating females. Animal Behaviour 2008, 75:217-227.
• [67]Hegglin I. Verteilung, Dichte, Aktivitätsmuster und Konkurrenz bei Steinbock (Capra ibex), Gemse (Rupicapra rupicapra) und Rothirsch (Cervus elaphus) in der Val Trupchun, Schweizerischer Nationalpark. Diploma thesis. University of Zurich, 1996.
• [68]Hofmann A. Das jahreszeitliche Verteilungsmuster und der Aesungsdruck von Alpensteinbock, Gemse, Rothirsch und Reh in einem begrenzten Gebiet im Oberengadin. Diploma thesis. University of Zurich, 1971.
• [69]Georgii B, Schröder W: Home range and activity patterns of male red deer (Cervus elaphus L.) in the alps. Oecologia 1983, 58:238-248.
• [70]Kamler JF, Jędrzejewska B, Jędrzejewski W. Activity Patterns of Red Deer in Białowieża National Park, Poland. 2007.
• [71]MeteoSwiss: IDA web. The data portal of MeteoSwiss for research and teaching [https://gate.meteoswiss.ch/idaweb/login.do?language=en]
• [72]Van Soest PJ. Nutritional ecology of the ruminant. Cornell University Press; 1994.
• [73]Jehle M, Hueni A, Damm A, D'Odorico P, Weyermann J, Kneubühler M, Schläpfer D, et al. APEX-Current status, performance and validation concept. In Sensors IEEE 2010 Waikoloa, HI, US; 2010: 533–537
• [74]Schläpfer D, Richter R: Geo-atmospheric processing of airborne imaging spectrometry data. Part 1: Parametric orthorectification. International Journal of Remote Sensing 2002, 23:2609-2630.
• [75]Richter R, Schläpfer D: Geo-atmospheric processing of airborne imaging spectrometry data. Part 2: Atmospheric/topographic correction. International Journal of Remote Sensing 2002, 23:2631-2649.
• [76]Evaluation of gross primary production (GPP) variability over several ecosystems in Switzerland using sun-induced chlorophyll fluorescence derived from APEX data. International Geoscience and Remote Sensing Symposium (IGARSS), Munich, Germany; 2012.
• [77]Smith EP, Rose KA: Model goodness-of-fit analysis using regression and related techniques. Ecological Modelling 1995, 77:49-64.
• [78]Roberts DA, Smith MO, Adams JB: Green vegetation, nonphotosynthetic vegetation, and soils in AVIRIS data. Remote Sensing of Environment 1993, 44:255-269.
• [79]R Core Team: R: A Language and Environment for Statistical Computing. R Foundation for Statistical Computing, Vienna, Austria; 2013.
• [80]Bjørneraas K, Moorter B, Rolandsen CM, Herfindal I: Screening global positioning system location data for errors using animal movement characteristics. The Journal of Wildlife Management 2010, 74:1361-1366.
• [81]Lyons AJ, Getz WM, R Development Core Team. T-LoCoH: Time Local Convex Hull Homerange and Time Use Analysis. R package version 1.16. 2014.
• [82]Dürr S, Ward MP: Roaming behaviour and home range estimation of domestic dogs in Aboriginal and Torres Strait Islander communities in northern Australia using four different methods. Preventive veterinary medicine 2014, 117:340-357.
• [83]T-LoCoH for R - Tutorial and Users Guide [http://tlocoh.r-forge.r-project.org/tlocoh_tutorial_2014-08-17.pdf]
• [84]Hosmer DW: Lemeshow S. Sturdivant RX, Applied logistic regression. John Wiley & Sons; 2013.
• [85]Fielding AH, Bell JF: A review of methods for the assessment of prediction errors in conservation presence/absence models. Environmental Conservation 1997, 24:38-49.
• [86]Pearce J, Ferrier S: Evaluating the predictive performance of habitat models developed using logistic regression. Ecological Modelling 2000, 133:225-245.
• [87]Venables WN, Ripley BD: Modern applied statistics with S. Statistics and computing. Springer, New York; 2002.
• [88]Robin X, Turck N, Hainard A, Tiberti N, Lisacek F, Sanchez J-C, et al.: pROC: an open-source package for R and S+ to analyze and compare ROC curves. BMC bioinformatics 2011, 12:77. BioMed Central Full Text
• [89]Fox J, Hong J: Effect displays in R for multinomial and proportional-odds logit models: Extensions to the effects package. Journal of Statistical Software 2009, 32:1-24.
• [90]Schröder J, Schröder W: Niche breadth and overlap in red deer Cervus elaphus, roe deer Capreolus capreolus and chamois Rupicapra rupicapra. Acta Zoologica Fennica 1984, 172:85-86.
• [91]Putman RJ: Competition and resource partitioning in temperate ungulate assemblies. Chapman & Hall, London; 1996.
• [92]De Boer WF, Prins HHT: Large Herbivores That Strive Mightily but Eat and Drink as Friends. Oecologia 1990, 82:264-274.
• [93]Chase JM, Leibold MA: Ecological niches: linking classical and contemporary approaches. University of Chicago Press, Chicago: London; 2003.
• [94]Connell JH: Diversity and the Coevolution of Competitors, or the Ghost of Competition Past. Oikos 1980, 35:131-138.
• [95]Kamler J: Feeding strategy of wild herbivores in habitats of limited food resources. Wildlife Biology in Practice 2011, 7:46-55.
• [96]Ripple WJ, Beschta RL: Wolves and the ecology of fear: Can predation risk structure ecosystems? BioScience 2004, 54:755-766.
• [97]Laundré JW, Hernández L, Altendorf KB: Wolves, elk, and bison: reestablishing the“ landscape of fear” in Yellowstone National Park, USA. Canadian Journal of Zoology 2001, 79:1401-1409.
• [98]Anderson TM, Hopcraft JGC, Stephanie E, Ritchie M, Grace JB, Olff H: Landscape-scale analyses suggest both nutrient and antipredator advantages to Serengeti herbivore hotspots. Ecology 2010, 91:1519-1529.
• [99]Wang G, Hobbs NT, Twombly S, Boone RB, Illius AW, Gordon IJ, et al.: Density dependence in northern ungulates: Interactions with predation and resources. Population Ecology 2009, 51:123-132.
• [100]Coulombe ML, Huot J, Massé A, Côté SD: Influence of forage biomass and cover on deer space use at a fine scale: A controlled-density experiment. Ecoscience 2011, 18:262-272.
• [101]Filli F: Ungulate research in the Swiss National Park: development, current issues and future challenges. In Huftierforschung im Schweizerischen Nationalpark. Nationalpark-Forschung in der Schweiz Edited by Filli F, Suter W. 2006, 9-29.
• [102]Andersen R, Linnell J, Solberg E: The future role of large carnivores in terrestrial trophic interactions: the northern temperate view. In Large herbivore ecology, ecosystem dynamics and conservation. Edited by Danell K, Bergström R, Duncan P, Pastor J. Cambridge Univ. Press, Cambridge; 2006:413-448.
• [103]Hebblewhite M, Merrill E, McDermid G: A Multi-Scale Test Of The Forage Maturation Hypothesis In A Partially Migratory Ungulate Population. Ecological Monographs 2008, 78:141-166.
• [104]Van Beest FM, Rivrud IM, Loe LE, Milner JM, Mysterud A: What determines variation in home range size across spatiotemporal scales in a large browsing herbivore? Journal of Animal Ecology 2011, 80:771-785.
• [105]Aublet J-F, Festa-Bianchet M, Bergero D, Bassano B: Temperature constraints on foraging behaviour of male Alpine ibex (Capra ibex) in summer. Oecologia 2009, 159:237-247.
• [106]Signer C, Ruf T, Arnold W: Hypometabolism and basking: The strategies of Alpine ibex to endure harsh over-wintering conditions. Functional Ecology 2011, 25:537-547.
• [107]Senft RL, Coughenour MB, Bailey DW, Rittenhouse LR, Sala OE, Swift DM: Large Herbivore Foraging and Ecological Hierarchies. BioScience 1987, 37:789-799.
• [108]Brivio F, Grignolio S, Brambilla A, Apollonio M: Intra-sexual variability in feeding behaviour of a mountain ungulate: size matters. Behavioral Ecology and Sociobiology 2014, 68:1649-1660.
• [109]Anderson K, Gaston KJ: Lightweight unmanned aerial vehicles will revolutionize spatial ecology. Frontiers in Ecology and the Environment 2013, 11:138-146.
• [110]Homolová L, Malenovský Z, Clevers JG, García-Santos G, Schaepman ME: Review of optical-based remote sensing for plant trait mapping. Ecological Complexity 2013, 15:1-16.
• [111]Ustin SL, Gitelson AA, Jacquemoud S, Schaepman M, Asner GP, Gamon JA, et al.: Retrieval of foliar information about plant pigment systems from high resolution spectroscopy. Remote Sensing of Environment 2009, 113:S67-S77.