Forage quality of savannas - Simultaneously mapping foliar protein and polyphenols for trees and grass using hyperspectral imagery

REMOTE SENSING OF ENVIRONMENT

卷:114

Article

Skidmore, Andrew K.^1,2  Ferwerda, Jelle G.¹  Mutanga, Onisimo¹  Van Wieren, Sipke E.²  Peel, Mike³  Grant, Rina C.⁴  Prins, Herbert H. T.²  Balcik, Filiz Bektas¹  Venus, Valentijn¹ 

[1] ITC Int Inst Geoinformat Sci & Earth Observat, NL-7500 AA Enschede, Netherlands

[2] Wageningen Univ, NL-6708 PD Wageningen, Netherlands

[3] Agr Res Council, ZA-1200 Nelspruit, South Africa

[4] SANParks, ZA-1305 Skukuza, South Africa

关键词: Forage;    Quality;    Remote sensing;    Hyperspectral;    Herbivory;    Foliar;    Nitrogen;    Protein;    Polyphenol;    Mopane;    Africa;    Savanna;   

DOI  :  10.1016/j.rse.2009.08.010

来源: Elsevier

【 摘 要 】

Savanna covers about two-thirds of Africa, with forage quantity and quality being important factors determining the distribution and density of wildlife and domestic stock. Testing hypotheses about the distribution of herbivores is hampered by the absence of reliable methods for measuring the variability of vegetation quality (e.g. biochemical composition) across the landscape. It is demonstrated that hyperspectral remote sensing fills this gap by revealing simultaneously the spatial variation of foliar nitrogen (crude protein) as well as the total amount of polyphenols, in grasses and trees. For the first time, the pattern of resources important for feeding preferences in herbivores (polyphenols and nitrogen) is mapped across an extensive landscape and the modeled foliar concentrations are shown to fit with ecological knowledge of the area. We explain how estimates of nitrogen (crude protein) and polyphenols may be scaled up from point-based observations to reveal their spatial pattern, and how the variation in forage quality can influence the management of savannas, including farms, communal grazing areas, and conservation areas. It provides a glimpse of the choices herbivores must face in selecting food resources of different qualities. (C) 2009 Elsevier Inc. All rights reserved.

【 授权许可】

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