Quantification of the Evaporation Rates from Six Types of Wetland Cover in Palo Verde National Park, Costa Rica

Abstract

The hydrology of tropical seasonal wetlands is affected by changes in the land cover. Changes from open water towards a vegetated cover imply an increase in the total evaporation flux, which includes the evaporation from open water bodies and the transpiration from vegetated surfaces. This study quantified the total evaporation flux of six covers of the Palo Verde wetland during dry season. The selected wetland covers were dominated by Neptunia natans (L.f.) Druce, Thalia geniculata L., Typha dominguensis Pers., Eichhornia crassipes (Mart.) Solms, a mixture of these species, and open water conditions. The plants were collected from the wetland and placed in lysimeters (59.1 L) built from plastic containers. The lysimeters were located in an open area near the meteorological station of the Organization for Tropical Studies (OTS). The evaporated water volume and meteorological data were collected between December 2012–January 2013. A completely randomized design was applied to determine the total evaporation (E), reference evaporation ( E ref , Penman-Monteith method) and crop coefficient ( K c ) for all the covers. T. geniculata (E: 17.0 mm d − 1 , K c : 3.43) and open water (E: 8.2 mm d − 1 , K c : 1.65) showed the highest and lowest values respectively, for daily evaporation and crop coefficient. Results from the ANOVA indicate that E. crassipes and N. natans were statistically different (p = 0.05) from T. dominguensis and the species mixture, while the water and T. geniculata showed significant differences with regard to other plant covers. These results indicate that the presence of emergent macrophytes as T. geniculata and T. dominguensis will increase the evaporation flux during dry season more than the floating macrophytes or open water surfaces.

Pan evaporation is increased by submerged macrophytes

“…According to a previous study in India (Kota, Rajasthan), water hyacinth evapotranspirated 26 % more water than free water surface in a 9-month experiment (Brezny et al, 1973). In the same place as this study, Anda et al (2016Anda et al ( , 2018 have shown that the presence of sediment increases the evaporation of the class A pans by an average of 12.7 %, and the submerged aquatic macrophytes by an average of 21.3 %, between 2014and 2016. Jiménez-Rodríguez et al (2019 reported that the observed E p were higher for aquatic plants than the open water cover in Palo Verde National Park, Costa Rica, between December 2012 andJanuary 2013 (45 d).…”

Estimation Standard And Seeded Pan Evaporation Using Modelling Approach

“…Anda et al (2016; have shown that the presence of sediment increases the evaporation of the Class A pans by an average of 12.7% and the submerged aquatic macrophytes by an average of 21.3%. Jiménez-Rodríguez et al, (2019) reported that the observed Ep were higher for aquatic plants than the open water cover. Concerning the relationship between pan treatments and meteorological variables, it can be concluded that positive correlation was observed with most meteorological variables, while a negative correlation was observed with RH.…”

Meteorological Controls on Water Table Dynamics in Fen Peatlands Depend on Management Regimes

“…Similar to the effect of rainfall, the effect of VPD on the water level was much higher at PD than at PW. However, evapotranspiration for the same dry days was substantially higher at PW than at PD, likely because of differences in vegetation composition and plant biomass (Jiménez-Rodríguez et al, 2019). The vegetation at PD is much shorter (around 20 cm in height) and mostly comprises grasses, while the vegetation at PW is dominated by taller sedges (Carex acutiformis), around 1 m in height (see Schwieger et al, 2020).…”