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Drone and Landsat imagery shows long-term change in vegetation cover along intermittent river

ScienceDaily (February 3, 2021)

Titre : Drone and Landsat imagery shows long-term change in vegetation cover along intermittent river

Study examines vegetation cover change in the Kuiseb river in the Namib desert

ScienceDaily (February 3, 2021)

Résumé
In the Namib Desert in southwestern Africa, the Kuiseb River, an ephemeral river which is dry most of the year, plays a vital role to the region. It provides most of the vegetation to the area and serves as a home for the local indigenous people, and migration corridor for many animals. The overall vegetation cover increased by 33% between 1984 and 2019, according to a Dartmouth study published in Remote Sensing.

Descriptif
The study area consisted of a 112-kilometer stretch of the lower Kuiseb River, which was comprised of 12 sites along the river, each of which was 500 meters wide. At each site, Morgan flew one to four unmanned aerial vehicle or drone flights to capture images of the woody vegetation cover along the river. One drone flight would take images with true color and then another flight would take images with false color using near infrared wavelengths of light, which are outside what our eyes can see. False color imagery allows one to distinguish vegetation from sand and soil, and differentiate the various types of vegetation and how healthy it may be.

The drone imagery revealed that five species of trees are part of the vegetation cover in the area : Acacia (Vachellia) erioloba, Faidherbia albida, Euclea pseudebenus, Tamrix usneoides, and Salvadora persica. A. erioloba and F. albida have been named national conservation priorities and their pods are an important food source to the livestock of the Topnaar (?Aonin), the indigenous people who live along the Kuiseb River. The Kuiseb also serves as a habitat and migration corridor for many animals, including the mountain zebra, leopard and ostrich.

Story Source  : Dartmouth College

Annonce (ScienceDaily)

Page publiée le 22 juin 2021