Rainfall Runoff Relationships for a Cloud Forest Watershed in Central America: Implications for Water Resource Engineering¹

Abstract

Caballero, Luis A., Alon Rimmer, Zachary M. Easton, and Tammo S. Steenhuis, 2012. Rainfall Runoff Relationships for a Cloud Forest Watershed in Central America: Implications for Water Resource Engineering. Journal of the American Water Resources Association (JAWRA) 48(5): 1022‐1031. DOI: 10.1111/j.1752‐1688.2012.00668.x Abstract: Understanding the basic relationships between rainfall and runoff is vital for effective management and utilization of scarce water resources. Especially, this is important in Central America with widespread potable water shortage during the dry months of the monsoon. Potential good water sources are cloud forests, but little information concerning its potential is available to water supply engineers. Our objective is to define rainfall‐runoff‐base flow relationships for a cloud forest catchment. Flumes were installed for measuring river flow in four subwatersheds in La Tigra National Park, Honduras. One of the four watersheds was a 636‐ha subwatershed (WS1) with 60% cloud forest coverage. Precipitation averaged 1,130 mm/yr over the entire basin. About half of the total rainfall became runoff for the cloud forest watershed whereas, for the adjacent undisturbed forested watershed, the total discharge was <20% of the amount of precipitation. Infiltration rates were generally greater than rainfall rates. Therefore, most rainfall infiltrated into the soil, especially in the upper, steep, and well‐drained portions of the watershed. Direct runoff was generated from saturated areas near the river and exposed bedrock. This research provides compelling evidence that base flow is the primary contributor to streamflow during both wet and dry seasons in cloud forest catchments. Protecting these flow processes over time is critical for the sustained provision of potable water.

Evaluating the bio-hydrological impact of a cloud forest in Central America using a semi-distributed water balance model

“…3a)). The model predicted that an average of 1.4 mm d -1 of rainfall exited the watershed as subsurface flow, which was nearly equal to the 1.6 mm d -1 obtained from baseflow separation technique (Caballero et al, 2012). …”

“…S2 Supplementary material). Water height were recorded on 10-minute intervals, and converted to volume using standardized rating curves (ISO, 1980;Caballero et al, 2012).…”

“…Our general objective is to increase knowledge on the interaction of hydrology and biological factors in cloud forests in Latin America by presenting a comprehensive analysis of physically based watershed model parameters using data from a recent study that measured rainfall and discharge from a cloud forest and three surrounding forested watersheds in the La Tigra National Park in Honduras (Caballero et al, 2012). Differences in model parameters between cloud forests and the other, non-cloud forest watersheds are used to infer the effect of cloud forests on bio-hydrological factors.…”

Analysing monthly sectorial water use and its influence on salt intrusion induced water shortage in urbanized deltas

“…Monsoon delta regions, in particular, suffer seasonal water shortages during the dry season as these regions are characterized by a pronounced uneven distribution of rainfall and runoff (Caballero, Rimmer, Easton, & Steenhuis, 2012;Cornforth, 2012;Islam, Chou, Kabir, & Liaw, 2010;Merz et al, 2003). These problems will likely be exacerbated with further global warming (Vörösmarty et al, 2000).…”

Water use in a heavily urbanized delta : scenarios and adaptation options for sectorial water use in the Pearl River Basin, China

“…Monsoon delta regions, in particular, suffer seasonal water shortages during the dry season as these regions are characterized by a pronounced uneven distribution of rainfall and runoff (Caballero et al 2012, Cornforth 2012, Islam et al 2010, Merz et al 2003. These problems will likely be exacerbated with further global warming (Vörösmarty et al 2000).…”