Showing posts with label carrying capacity. Show all posts
Showing posts with label carrying capacity. Show all posts

Tuesday, 15 June 2021

The Population Dynamics of the Luangwa (Zambia) Common Hippopotamus (Hippopotamus amphibius) during the Period 1952 – 2015 | Chapter 5 | International Research in Environment, Geography and Earth Science Vol. 9

 The population size of hippopotamus (Hippopotamus amphibius Linnaeus 1758) in Zambia's Luangwa valley was previously assessed for the period 1976-2008 and repeated 2009-2015, and it was discovered to have reached and maintained a carrying capacity K of 6000 individuals over a 165 km river stretch. The riverbank count method, as used in previous studies, was used in this study, which spanned the years 2009 to 2015. In 1976, a 165-kilometer stretch of land was set aside for intensive population monitoring using the same survey methods. The results of this monitoring revealed that the population experienced high densities of up to 42 hippopotami/km between 1976 and 2008. The method entailed counting individuals and locating hippopotamus schools using GPS. During the period 2009-2015, the population oscillated in irregular cycles above and below K of 6000, remaining within the carrying capacity band of 3000 people are involved. The highest population size was 7,862 hippopotami with a density of 48/km in 2015, and the lowest population size was 4501 hippopotami with a density of 27/km in 1978. Between 1976 and 2008, and 2009 and 2015, the population fluctuated between 5000 and 8000 people, indicating that the population had reached its asymptote. Plot of population size from 1976 to 2015 using a population model that was a hybrid of less accurate regulation and a stable limit cycle. Environmental resistance was blamed for the slowing of population growth at K and the oscillations. More research is needed to determine the impact of climate change on population size and density fluctuations in order to determine whether K will rise or fall.

Author (s) Details

Chansa Chomba

School of Agriculture and Natural Resources, Mulungushi University, Kabwe, Zambia

Twakundine Simpamba
Department of Research, Chinzombo Research Centre, Mfuwe, Zambia.

Vincent Nyirenda
Department of Research, Planning, Information and Veterinary Services, Chilanga, Zambia.

View Book :- https://stm.bookpi.org/IREGES-V9/article/view/1509

Saturday, 19 September 2020

Critical Study on Characteristics of the Gadoudhé Course Vegetation in the Rural Area of Fabidji (Niger) | Chapter 9 | Research and Development in Agricultural Sciences Vol. 3

 

This study on the characteristics of the vegetation (herbaceous and woody) Gadoudhé course was
conducted in the rural area of Fabidji (Niger). Within 126 plots that have been set through 4 transects. Aligned quadrat points method allowed
taking an inventory of the herbaceous. The herbaceous biomass was evaluated by the method of the full harvest. After making the list of woody species, the measures on dendrometric parameters were
conducted. The regeneration of the species has been appreciated by the count of live and dead
discards. 37 were inventoried. Among these 27 species are herbaceous plants. The most represented
families of grasses are the Poaceae, Fabaceae, Amaranthaceae and the Convolvulaceae. Residual
biomass is 471.1 kg DM/ha of « qualified » fodder. What gives an estimated carrying capacity to 0.041 TLU/ha/year? As for the wood, they are represented by 10 species, especially represented by the Combretaceae. The structure of the settlement shows average individuals of height and diameter. Basal area was evaluated to 0.01 m
2/ha at a density of 13.75 individuals per hectare. The regeneration of seeding presents a density of releases per hectare 1020.91.
The results obtained highlight the need to think about a layout of the route to ensure its sustainability.

Author (s) Details

Ibrahim Djibo
Faculté d’Agronomie, Université Abdou Moumouni, laboratoire d’insémination artificielle et de production d’azote liquide, BP n° 10960 Niamey, Niger and École Inter-États des Sciences et Médecines Vétérinaires, Université Cheick Anta Diop, laboratoire de physiologie et de pharmacodynamie, BP n° 5 077 Dakar – Fann, Sénégal

Mani Mamman
Département productions animales, Institut National de la Recherche Agronomique du Niger, BP n° 429 Niamey, Niger.


Chaibou Issa
Université Dan Dicko Dankoulodo de Maradi, BP no 465 Maradi, Niger.

Oumar Sarr
Faculté des sciences et Techniques, Université Cheick Anta Diop, laboratoire d’Écologie et d’Ecohydrologie, BP n° 5 005 Dakar – Fann, Sénégal.

Amy Bakhoum
Faculté des sciences et Techniques, Université Cheick Anta Diop, laboratoire d’Écologie et d’Ecohydrologie, BP n° 5 005 Dakar – Fann, Sénégal.

Hamani Marichatou
Faculté d’Agronomie, Université Abdou Moumouni, laboratoire d’insémination artificielle et de production d’azote liquide, BP n° 10960 Niamey, Niger.

E. Léonard Akpo
Faculté des sciences et Techniques, Université Cheick Anta Diop, laboratoire d’Écologie et d’Ecohydrologie, BP n° 5 005 Dakar – Fann, Sénégal.

Moussa Assane
École Inter-États des Sciences et Médecines Vétérinaires, Université Cheick Anta Diop, laboratoire de physiologie et de pharmacodynamie, BP n° 5 077 Dakar – Fann, Sénégal.

View Book :-
http://bp.bookpi.org/index.php/bpi/catalog/book/266