@ElectronicSource{AlcāntaraNovSteBarBon::EnFaAs,
             abstract = "The study of chlorophyll-a concentration in flood pulsed wetlands 
                         has been based mostly on datasets obtained at different sites or 
                         along track lines occupied during cruises. In situ water data, 
                         however, are limited in time and space. This is a particularly 
                         serious constrain in remote regions of difficult access, such as 
                         the Brazilian Amazon floodplain waters. Moreover, in situ sampling 
                         monitoring has a high probability of undersampling. Some authors 
                         have used satellite imagery to address the wide range of spatial 
                         and temporal variability of chlorophyll-a concentration in the 
                         Brazilian Amazon floodplain. However, the authors have estimated 
                         the chlorophyll concentration in a synoptic view. Also, they dont 
                         explain the relationship between the chlorophyll concentration and 
                         other environmental parameters that might explain the reported 
                         time and space variability. Long-term environmental time series of 
                         continuously collected data are fundamental to identify and 
                         classify pulses and determining their role in aquatic systems. 
                         Based on this, this paper with the objective of analyze the 
                         chlorophyll-a concentration time series and their relationship 
                         with others environmental parameters uses in situ daily mean 
                         collected limnological (chlorophyll-a concentration, water level, 
                         water surface temperature, pH and turbidity) and meteorological 
                         (wind intensity, relative humidity and short wave radiation) 
                         through an automatic system (Integrated System for Environmental 
                         Monitoring-SIMA). SIMA is a set of hardware and software designed 
                         for data acquisition and real time monitoring of hydrological 
                         systems. The data are collected in preprogrammed time interval (1 
                         hour) and are transmitted by satellite in quasi-real time for any 
                         user in a range of 2500 km from the acquisition point. We used 
                         Pearson correlation to determine the quantitative relation between 
                         chlorophyll time series and others environmental parameters. The 
                         periods of high variability will be studied using the Fourier 
                         power spectrum and the time-frequency structure of chlorophyll 
                         time series will be analyzed using the wavelet power spectrum. To 
                         show the relationship between chlorophyll and the significantly 
                         time series highlighted by Pearsons correlation the cross wavelet 
                         analysis was carried out and the coherence and phase analyzed. The 
                         time series of chlorophyll-a shows two high peaks (47 \μg/L 
                         and 53.30 \μg/L) of concentration during a year: first 
                         during the rising water and second during the low water level. A 
                         little peak was observed during the high water level (10 
                         \μg/L). For the most part of rising, high and falling water 
                         level, the chlorophyll concentration is often low (from 2.26 
                         \μg/L to 9.11 \μg/L). The causes of this were 
                         discussed. The relationship between the chlorophyll-a time series 
                         and others parameters were analyzed using the Cross Wavelet and 
                         coherence and phase concepts. With periodicities ranging from 2-60 
                         days the chlorophyll-a concentration well agrees with turbidity 
                         and water level; and coherence ~1 and in-phase for rising and low 
                         water period. Water level dynamics and turbidity explain 68% of 
                         the chlorophyll-a time series variability.",
              address = "S{\~a}o Jos{\'e} dos Campos",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {Institut de Recherche pour le 
                         D{\'e}veloppement}",
               author = "Alc{\^a}ntara, Enner and Novo, Evlyn and Stech, Jos{\'e} and 
                         Barbosa, Cl{\'a}udio and Bonnet, Marie-Paule",
             keywords = "Time series analysis, Amazon floodplain, Limnology.",
             language = "en",
       lastupdatedate = "2009-09-26",
            publisher = "Instituto and Nacional and de and Pesquisas and Espaciais",
                  ibi = "8JMKD3MGP8W/365FBKP",
                  url = "http://urlib.net/ibi/8JMKD3MGP8W/365FBKP",
           targetfile = "v1.pdf",
                title = "Environmental factors associated with long-term changes in 
                         chlorophyll-a concentration in the Amazon floodplain",
         typeofmedium = "On-line",
        urlaccessdate = "29 jun. 2024"
}