bin
Forest duct of Nun River basin, Bayelsa State, Nigeria
Nigeria, Bayelsa, Odi
Nun River is the longest (160km) continuation of the Niger River. The Nun River begins near the village of Aboh, where the Niger River splits in two, forming Nun and Forcados, flows through the rain forests, swamps and mangroves, and empties into the Gulf of Guinea. Flooding from monsoon rains lasts from June to September, then the water level drops, and in February, with the arrival of the flood waters from the Niger River, rises again.
Forest rivers and streams of the Nun River basin are home to many species of fish and other aquatic organisms. Although oil production causes serious damage to the local nature, yet in clean rivers significant biodiversity can be found. Mainly semi-aquatic plants grow in places where sun can reach the earth surface through the trees.
- Submitted by
- Biswarup Goon
- Approved by
- Ad Konings & Anton Lamboj
- Geographical region
- Western Africa
- Drainage Basin
- Nun river basin
- River catchment
- Niger river
- Water body type
- Stream
- Water body name
- Nameless
- Water body part
- Water body course
- Upper course
- Water body: tributary of
- River
- Tributary name
- Nun
Videos above and below water
Warning: Undefined variable $fish_parent in /home/biotopea/public_html/wp-content/themes/bap/content-bin.php on line 55
Water Chemistry
Water information
- Water type
- fresh-water
- Water color
- Black water
- Water transparency
- Medium
- Concentration of sediments
- Medium
- Water temperature
- 24 °C
- Water flow/curent
- Slow
Chemical parameters
- pH
- 6.5
- Conductivity
- 6.5
- GH
- 22 mg/l
- dGH
- KH
- 20 mg/l
- dKH
- Dissolved Oxygen
- 110 %
Substrate in nature
- Sand
- Orange
- Pebble/Gravel
- Beige
- Stone
- Reddish
- Stone form
- Irregular
- Silt/Mud
- Brown
- Leaves
- Adundant
- Driftwood
- Many
- Submerged terrestrial vegetation
- Yes
Aquatic Biotope
- Date of collecting
- 25/03/2022
- Collecting area
- River bank
- Water depth
- 0,5m
- Air temperature
- 26 °C
- Sunlight
- Filtered/dappled sun
Environment
- Environment
- Affected by human activity
- Affected by human activity
- Agriculture
- Agriculture
- Little
- Surrounding area
The river bank is covered with trees and large clump of fern like Bolbitis heudelotii. The bed is filled with riversand, clay and porous stones and covered with dry leaves. Various types of worms and flies are lived in the rainforest through which the river is passing. Dry and ripe fruits, insects are the main food source of the fishes of Nun river.
- Underwater landscape
Mostly there are Water lilies (Nymphaea), Crinum, Anubias on the edges of rivers but the middle parts of streams are devoid of plant growth, only with lots of rocks and dead leaves. Though there are some islands of plant growth but more made up of overhanging growth from shore based plants.
The bottom is composed of sand, gravel and sporadic larger stones . Roots of semi submerge vegetations makes hiding place for fishes and other aquatic animals. Fruits’ shells, seed pods, barks provide shelter and suitable place for egg-laying.
Fishes:
- Pantodon buchholzi (Pantodontidae) – common
- Pelvicachromis pulcher (Cichlidae ) – very common
- Polypterus endlicheri (Polypteridae) – common
- Gnathonemus petersii (Mormyridae) – rare
- Aphyosemion bitaeniatum (Nothobranchiidae) – common
Amphibians:
- Hymenochirus boettgeri (Pipidae) – very common
Aquatic plants:
- Anubias barteri var. glabra Araceae) – common
- Anubias barteri var. nana (Araceae) – very common
- Bolbitis heudelotii (Dryopteridaceae) – common
- Crinum calamistratum (Amaryllidaceae) – rare
- Ceratopteris thalictroides (Pteridaceae) – common
- Pistia stratiotes (Araceae) – very common
- Threats to ecology
Bridge construction activities within the channel of the Nun River have adverse effect on the water quality. The bridge construction activities also have the potential to cause a temporary increase in suspended sediments. Aquatic habitat will be disturbed in the vicinity of the construction area. Aquatic life uses of this portion of the Nun River will be negatively impacted. The bridge structure itself was observed during this study to cause a constant upwelling of sediments around the bridge location and is confirmed by very high turbidity values of 64NTU recorded in the area and downstream of the bridge location. The distribution of particle size fractions shows a high proportion of sand particles at the Bridge stations; indicative of higher energy environment.
Sediments in the study area were generally acidic (ranging from 4.21-5.61): acidic sediments can have an adverse effect on fisheries distribution and other benthic organisms. Available Phosphate values of 2.71-17.24mg/l and Nitrate values of 3.11-13.4mg/l recorded in this study were higher than those in other studies. Bridge construction activities within the cannel of the Nun River have adverse effect on the sediment quality.
Crude oil industry of Nigeria is another threat to Nun river’s aquatic system. Oil layer on the river water surface makes suffocating environment for fishes,crustaceans and amphibians of the river. Dissolved oxygen ratio is decreasing day by day.
Riparian zone
- Trees near the aquatic habitat
-
Many - Bolbitis heudelotii (Dryopteridaceae)
