کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5770364 | 1629407 | 2018 | 13 صفحه PDF | دانلود رایگان |
- Soil erosion is relatively understudied in dry tropical settings.
- Unpaved road runoff occurred more than twice as often as on natural hillslopes.
- Unpaved road erosion was 6 to 200 times greater than background rates.
- Dry tropical soils are in a very vulnerable state of equilibrium.
- Disturbing only a fraction of land can lead to significant increases in erosion.
Accelerated soil loss due to human land use is still one the most critical environmental problems as it can degrade both soils and downstream resources. Major gaps still exist in our knowledge of erosion, particularly in the dry tropics that make up about a fourth of the world's tropical landmass. The Insular Caribbean presents a particular need because erosion here has deleterious effects on soils, nearshore coral reefs, and their associated myriad of ecosystem services. Through plot-scale monitoring of runoff and sediment production over an eleven-month period, this study quantified the impacts of land disturbance on runoff development and sediment production relative to background rates on disturbed surfaces (i.e., roads) in a dry tropical area of Puerto Rico. Results demonstrate that unpaved road surfaces have the potential to generate runoff two to three-and-a-half times more frequently than under natural conditions and that they can produce sediment at rates that are between six to two-hundred times greater than background. These results suggest that land development in small dry-tropical coastal watersheds can potentially induce an increase in the frequency of runoff and sediment delivery into coastal waters even when a relatively small percentage of the land is disturbed. Soil formation simply cannot keep up with accelerated erosion, which implies a net exhaustion of the soil mantle and a decay of the ecological services it provides. Offsetting these soil losses will require implementing proven conservation practices to protect soils and coral reef ecosystems in this and other dry tropical settings.
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Journal: Geoderma - Volume 310, 15 January 2018, Pages 107-119