{{short description|River in the Tembien highlands of Ethiopia}} {{Use dmy dates|date=March 2020}} {{Infobox river | name = May Selelo | name_etymology = | image = May Selelo in Dasarawat 2.jpg | image_size = | image_caption = The May Selelo River at [[Dasarawat]] | pushpin_map = Ethiopia | pushpin_map_size = | pushpin_map_caption = May Selelo River in [[Degua Tembien|Dogu’a Tembien]] and [[Abergele]] | pushpin_map_alt = | subdivision_type1 = Country | subdivision_name1 = [[Ethiopia]] | subdivision_type2 = Region | subdivision_name2 = [[Tigray Region]] | subdivision_type3 = District (''woreda'') | subdivision_name3 = [[Degua Tembien|Dogu’a Tembien]] <!---------------------- PHYSICAL CHARACTERISTICS -->| length = {{Convert|19.5|km|mi|abbr=on}} | width_min = | width_avg = {{Convert|18|m|ft|abbr=on}} | width_max = | depth_min = | depth_avg = | depth_max = <!---------------------- BASIN FEATURES --> | source1 = Gunfan | source1_location = Mennewe in [[Simret]] municipality | source1_coordinates = | source1_elevation = {{Convert|2200|m|ft|abbr=on}} | mouth = [[Giba River]] | mouth_location = Just upstream from Giba bridge in [[Abergele]] district | mouth_coordinates = {{coord|13.463|N|39.028|E|display=inline, title}} | mouth_elevation = {{Convert|1370|m|ft|abbr=on}} | river_system = Seasonal/permanent river | basin_size = | basin_landmarks = Mennawe monastery and birthplace of [[Ras Alula]] | basin_population = | custom_label = Topography | custom_data = Mountains and deep gorges | extra = | progression = [[Giba River|Giba]]→ [[Tekezé River|Tekezé]]→ [[Atbarah River|Atbarah]]→ [[Nile]]→ [[Mediterranean Sea]] }} The '''May Selelo''' is a river of the [[Nile]] basin. Rising in the mountains of [[Degua Tembien|Dogu’a Tembien]] in northern [[Ethiopia]], it flows southward to empty in the [[Giba River|Giba]] and [[Tekezé River]].<ref name="chapmap">{{cite book |last1=Jacob |first1=M. and colleagues |title=Geo-trekking map of Dogu'a Tembien (1:50,000). In: Geo-trekking in Ethiopia's Tropical Mountains - The Dogu'a Tembien District |date=2019 |publisher=SpringerNature |isbn=978-3-030-04954-6 |url=https://www.springer.com/gp/book/9783030049546}}</ref> [[File:DT drainage.jpg|thumb|upright=2.5|The river in the [[Drainage system (geomorphology)#Radial drainage pattern|radial drainage network]] of Dogu’a Tembien]]
== Characteristics == It is a confined ephemeral river, locally [[meander]]ing in its narrow alluvial plain, with an average slope gradient of 43 metres per kilometre. With its tributaries, the river has cut a deep gorge.<ref name="chapriver">{{cite book |last1=Amanuel Zenebe |first1=and colleagues |title= The Giba, Tanqwa and Tsaliet rivers in the headwaters of the Tekezze basin. In: Geo-trekking in Ethiopia's Tropical Mountains - The Dogu'a Tembien District |date=2019 |publisher=SpringerNature |isbn=978-3-030-04954-6 |doi=10.1007/978-3-030-04955-3_14 }}</ref>
==Flash floods and flood buffering== Runoff mostly happens in the form of high runoff discharge events that occur in a very short period (called [[flash floods]]). These are related to the steep topography, often little vegetation cover and intense convective rainfall. The peaks of such flash floods have often a 50 to 100 times larger discharge than the preceding [[baseflow]].<ref name="chapriver"/> [[File:Affluent to May Selelo at Adenna.jpg|thumb|Affluent to May Selelo at [[Adenna]]]] The magnitude of floods in this river has been decreased due to interventions in the catchment. On some steep slopes, [[exclosure]]s have been established; the dense vegetation largely contributes to enhanced [[infiltration (hydrology) |infiltration]], less flooding and better [[baseflow]].<ref>{{cite journal |last1= Descheemaeker|first1= K. and colleagues| title= Runoff on slopes with restoring vegetation: A case study from the Tigray highlands, Ethiopia. |journal= Journal of Hydrology |date=2006 |volume=331 |issue=1–2 |pages=219–241 |doi= 10.1016/j.still.2006.07.011|url= https://biblio.ugent.be/publication/378900/file/738003.pdf |hdl= 1854/LU-378900 |hdl-access= free }}</ref> Physical conservation structures such as [[Terrace (earthworks)|stone bunds]]<ref>{{cite journal |last1= Nyssen|first1= Jan|last2= Poesen|first2= Jean|last3= Gebremichael|first3= Desta|last4= Vancampenhout|first4= Karen|last5= d'Aes|first5= Margo|last6= Yihdego|first6= Gebremedhin|last7= Govers|first7= Gerard|last8= Leirs|first8= Herwig|last9= Moeyersons|first9= Jan|last10= Naudts|first10= Jozef|last11= Haregeweyn|first11= Nigussie|last12= Haile|first12= Mitiku|last13= Deckers|first13= Jozef|title= Interdisciplinary on-site evaluation of stone bunds to control soil erosion on cropland in Northern Ethiopia. |journal= Soil and Tillage Research |date=2007 |volume=94 |issue=1 |pages=151–163 |doi= 10.1016/j.still.2006.07.011|hdl= 1854/LU-378900|url= https://biblio.ugent.be/publication/378900|hdl-access= free|url-access= subscription}}</ref><ref>{{cite journal |last1= Gebeyehu Taye and colleagues| title= Evolution of the effectiveness of stone bunds and trenches in reducing runoff and soil loss in the semi-arid Ethiopian highlands. |journal= Zeitschrift für Geomorphologie|date=2015 |volume=59 |issue=4 |pages=477–493 |doi= 10.1127/zfg/2015/0166}}</ref> and [[check dam]]s also intercept runoff.<ref>{{cite journal |last1= Nyssen|first1= J.|last2= Veyret-Picot|first2= M.|last3= Poesen|first3= J.|last4= Moeyersons|first4= J.|last5= Haile|first5= Mitiku|last6= Deckers|first6= J.|last7= Govers|first7= G.|title= The effectiveness of loose rock check dams for gully control in Tigray, Northern Ethiopia. |journal= Soil Use and Management |date=2004 |volume=20 |pages=55–64 |doi= 10.1111/j.1475-2743.2004.tb00337.x}}</ref><ref>{{cite journal |last1= Etefa Guyassa and colleagues|title= Effects of check dams on runoff characteristics along gully reaches, the case of Northern Ethiopia. |journal= Journal of Hydrology |date=2017 |volume=545 |issue=1 |pages=299–309 |doi= 10.1016/j.jhydrol.2016.12.019|url= https://biblio.ugent.be/publication/8518957 |hdl= 1854/LU-8518957 |hdl-access= free }}</ref>
==Transhumance towards the gorge== [[Transhumance in Ethiopia|Transhumance]] takes place in the summer rainy season, when the lands near the villages are occupied by crops. Young shepherds will take the village cattle down to the gorge and overnight in small caves. The gorges are particularly attractive as a transhumance destination zone, because there is water and good growth of semi-natural vegetation.<ref name="trans">{{cite journal |title=Transhumance in the Tigray highlands (Ethiopia) |journal=Mountain Research and Development |date=2009 |volume=29 |issue=3 |pages=255–264 |doi=10.1659/mrd.00033 |last1=Nyssen |first1=Jan |last2=Descheemaeker |first2=Katrien |last3=Zenebe |first3=Amanuel |last4=Poesen |first4=Jean |last5=Deckers |first5=Jozef |last6=Haile |first6=Mitiku |doi-access=free |hdl=1854/LU-854326 |hdl-access=free }}</ref>
==Boulders and pebbles in the river bed== Boulders and pebbles encountered in the river bed can originate from any location higher up in the catchment. In the uppermost stretches of the river, only rock fragments of the upper lithological units will be present in the river bed, whereas more downstream one may find a more comprehensive mix of all lithologies crossed by the river. From upstream to downstream, the following lithological units occur in the catchment.<ref>{{cite book |last1=Sembroni |first1=A. |last2=Molin |first2=P. |last3=Dramis |first3=F. |title=Regional geology of the Dogu'a Tembien massif. In: Geo-trekking in Ethiopia's Tropical Mountains — The Dogu'a Tembien District |date=2019 |publisher=SpringerNature |isbn=978-3-030-04954-6 |url=https://www.springer.com/gp/book/9783030049546}}</ref> * [[Alaji Basalts|Upper basalt]] * [[Intra-volcanic sedimentary rock in North Ethiopia|Interbedded lacustrine deposits]] * [[Ashangi Basalts|Lower basalt]] * [[Amba Aradam Formation]] * [[Antalo Limestone]] * [[Quaternary]] freshwater [[tufa]]<ref>{{cite journal |last1=Moeyersons |first1=J. and colleagues |title=Age and backfill/overfill stratigraphy of two tufa dams, Tigray Highlands, Ethiopia: Evidence for Late Pleistocene and Holocene wet conditions. |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |date=2006 |volume=230 |issue=1–2 |pages=162–178 |bibcode=2006PPP...230..165M |doi=10.1016/j.palaeo.2005.07.013 }}</ref> * [[Adigrat Sandstone]]
==Two districts== [[File:May Selelo headwaters2.jpg|thumb|May Selelo headwaters]] Along its course, this river passes through two woredas: [[Degua Tembien|Dogu’a Tembien]] for the headwaters, and [[Abergele]] for the larger part of its course.<ref name="chapmap"/>
[[File:May Selelo in Dasarawat1.jpg|thumb|Trek '''S2''' crosses May Selelo in [[Dasarawat]]]] ==Trekking along the river== Trekking routes have been established across and along this river.<ref name="jnroutes">{{cite book |title=Description of trekking routes in Dogu'a Tembien. In: Geo-trekking in Ethiopia's Tropical Mountains - The Dogu'a Tembien District |date=2019 |publisher=SpringerNature |isbn=978-3-030-04954-6 |url=https://www.springer.com/gp/book/9783030049546}}</ref> The tracks are not marked on the ground but can be followed using downloaded .GPX files.<ref>[https://www.openstreetmap.org/traces/tag/nyssen-jacob-frankl Public GPS traces tagged with nyssen-jacob-frankl | OpenStreetMap]</ref> * Trek '''8''', across the river in [[Kalazban]] village * Trek '''S2''', across the river in [[Dasarawat]] village In the rainy season, flash floods may occur and it is advised not to follow the river bed. At times it may be impossible to cross the river in the rainy season.<ref>{{cite book |chapter=Logistics for the Trekker in a Rural Mountain District of Northern Ethiopia|date=2019 |publisher=Springer-Nature |pages=537–556 |doi=10.1007/978-3-030-04955-3_37 |title=Geo-trekking in Ethiopia's Tropical Mountains |series=GeoGuide |last1=Nyssen |first1=Jan |isbn=978-3-030-04954-6 }}</ref>
== See also == * [[List of Ethiopian rivers]]
==References== {{reflist}}
[[Category:Rivers of Ethiopia]] [[Category:Dogu'a Tembien]] [[Category:Tigray Region]] [[Category:Nile basin]]