Page 366 - FRUTAS DEL TRÓPICO

366 Frutas del trópico

Watershed implications

All water, including that used for irrigation, is part of a more complex cycle: the hydrologic

cycle (Fig. 3). Therefore, irrigation not only influences crop production but also other compo-

nents of the hydrologic cycle. Water that is used for irrigation is generally from groundwater

or surface water reservoirs. Removal of waters from these reservoirs may alter ecosystem
services provided by stream systems, such as nutrient cycling or biological decomposition.

Additionally, if irrigation results in surface runoff or percolation to groundwater, water quality

may be negatively altered in groundwater and surface water reservoirs. Over irrigation may be

linked to intensification of downstream surface water eutrophication (or nutrient enrichment).

As waters become eutrophic, they are characterized by decreased oxygen concentrations, in-

creased nutrient concentrations, increased suspended solids, changes in the food web structure

and fish species, and decreasing light penetration (Henderson-Sellers and Markland, 1987). This
is particularly harmful if surface waters are a drinking water supply. The primary groundwater

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