@Article{OliveiraBrMoShBeSaAr:2017:EvMOEs,
               author = "Oliveira, Gabriel de and Brunsell, Nathaniel A. and Moraes, 
                         Elisabete Caria and Shimabukuro, Yosio Edemir and Bertani, Gabriel 
                         and Santos, Thiago V. dos and Arag{\~a}o, Luiz Eduardo Oliveira e 
                         Cruz de",
          affiliation = "{University of Kansas} and {University of Kansas} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {University of Minnesota} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)}",
                title = "Evaluation of MODIS-based estimates of water-use efficiency in 
                         Amazonia",
              journal = "International Journal of Remote Sensing",
                 year = "2017",
               volume = "38",
               number = "19",
                pages = "5291--5309",
             abstract = "This study aimed to assess the spatial-temporal patterns of 
                         water-use efficiency (WUE) obtained through MODIS gross primary 
                         productivity (GPP) and evapotranspiration (ET) products (MOD17 for 
                         GPP and MOD16 for ET) in the Upper Tapajos and Curua-Una River 
                         basins, located in the oriental flank of the Amazon region, and to 
                         validate the results with flux tower measurements within the 
                         Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) 
                         project. The spatial variation of WUE was primarily related to the 
                         larger presence of forested areas in the Upper Tapajos River basin 
                         (western part) compared with the Curua-Una River basin (eastern 
                         part), which is situated within the so-called arc of 
                         deforestation. Temporally, WUE showed a pronounced seasonal 
                         pattern, varying with the dry and wet seasons in the region. A 
                         decrease of similar to 3% in WUE was observed during the dry 
                         season, which was related to the low water availability and 
                         increased vapour pressure deficit during the dry period, which 
                         induces stomatal closure, leading to a decline in the 
                         photosynthetic rate. Comparison between the WUE estimates obtained 
                         by MODIS data and observations from the LBA towers showed an 
                         average error of 17%, varying between similar to 12% and similar 
                         to 28% for the different sites. MODIS WUE depends on the accuracy 
                         of both GPP and ET estimation. In this sense, we highlight that 
                         improvements in both MODIS GPP and ET products are necessary and 
                         should focus on reducing the uncertainties related to the 
                         biophysical vegetation parameters and meteorological data that 
                         serve as input information in the algorithms.",
                  doi = "10.1080/01431161.2017.1339924",
                  url = "http://dx.doi.org/10.1080/01431161.2017.1339924",
                 issn = "0143-1161",
             language = "en",
           targetfile = "Oliveira_evaluation.pdf",
        urlaccessdate = "27 abr. 2024"
}