We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Detecting linear trend of reference evapotranspiration in irrigated farming areas in Brazil's semiarid region.
- Authors
Cabral Júnior, Jório Bezerra; Silva, Cláudio Moisés Santos e; de Almeida, Hermes Alves; Bezerra, Bergson Guedes; Spyrides, Maria Helena Constantino
- Abstract
Northeast Brazil's semiarid region is characterized by water deficit. However, little is known about the trends in joint water loss by evaporation and transpiration (evapotranspiration) in the region. Thus, this study aimed to analyze indications on the linear trend of reference evapotranspiration (ET0) in the monthly, annual, and interdecadal scales in irrigated agricultural areas in the microregions of Juazeiro, Bahia State (9° 24' S; 40° 26' W and 375.5 m), and Petrolina, Pernambuco State (09° 09' S, 40° 22' W, and 376 m). For this purpose, we used a set of daily meteorological data, collected from January 1, 1976, to December 31, 2014. Daily ET0 values were estimated by the FAO's Penman-Monteith equation (ET0PM). The main statistical tests used were the nonparametric Mann-Kendall test, the Sen test to detect the magnitude of the trend, and the Pettitt test to detect the start of the trend. For all tests, statistical significance was 5% and/or 1%. Analysis of variance (ANOVA) was also applied to identify significant differences between the mean interdecadal values for each season. The results showed a significant decreasing trend for ET0 in both Juazeiro (α = 5%) and Petrolina (α = 1%), with declines of 14.5 mm/year (Juazeiro) and 7.7 mm/year (Petrolina) and that this trend started in 1996. Probably, the ET0 decrease was associated with the increase in the irrigated agricultural areas, and the lake formed upstream from the areas by the construction of Sobradinho Dam.
- Subjects
BRAZIL; IRRIGATION farming; ARID regions; EVAPOTRANSPIRATION; STATISTICAL significance; ANALYSIS of variance; DAM design &; construction; EVAPORATION (Meteorology)
- Publication
Theoretical & Applied Climatology, 2019, Vol 138, Issue 1/2, p215
- ISSN
0177-798X
- Publication type
Article
- DOI
10.1007/s00704-019-02816-w