Biological Parameters of the Red Pandora (Pagellus bellottii Steindachner, 1882) in Soumbedioune, Senegal, West Africa
Waly Ndiaye,
Alassane Sarr,
Patrick Diédhiou
Issue:
Volume 10, Issue 6, December 2022
Pages:
115-122
Received:
3 October 2022
Accepted:
21 October 2022
Published:
8 December 2022
DOI:
10.11648/j.ajls.20221006.11
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Abstract: New information on the reproductive biology of Pagellus bellottii (Steindachner, 1882) a Sparid fish in Senegalese waters is provided in this study. Little aspects on the reproductive biology of this fish are reported in Senegal, West Africa. The objective of the study is to examine the length-weight relationship, the condition factor and the reproductive parameters of P. bellottii from the Senegalese waters. A total of 360 specimens (males = 197 and females = 163) bought from fishermen were used for the study. Specimens were collected monthly (thirty individuals per month) from October 2019 to September 2020 from Soumbedioune of Western part of Dakar, Senegal. Each individual was measured with an ichthyometer and weighed with a precision balance. For dissected individuals, sex was determined by macroscopic observation of the gonads. The gonads were extracted to calculate the Gonadosomatic Index. The length-weight relationship gave a negative allometric growth for both sexes. The value of “k” being greater than 1; the species was in good condition in this environment. The sex ratio (1:0.82) was favourable to males. The reproductive period was from March to June with a spawning peak in April for both sexes. Males and females had size at first sexual maturity at 178- and 180-mm total length, respectively. Males matured at smaller sizes than females. The data obtained in this study on some aspects of the reproductive biology of P. bellottii will be essential for better management of fish stocks in Senegal and in the sub-region.
Abstract: New information on the reproductive biology of Pagellus bellottii (Steindachner, 1882) a Sparid fish in Senegalese waters is provided in this study. Little aspects on the reproductive biology of this fish are reported in Senegal, West Africa. The objective of the study is to examine the length-weight relationship, the condition factor and the repro...
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Correlation of Tree Diameter, Height and Biodiversity with Soil N, P and K
Shreejana Panthi,
Ram Asheshwar Mandal,
Ajay Bhakta Mathema
Issue:
Volume 10, Issue 6, December 2022
Pages:
123-130
Received:
8 October 2022
Accepted:
26 October 2022
Published:
29 December 2022
DOI:
10.11648/j.ajls.20221006.12
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Abstract: This research was done to assess effect of soil nutrients (N, P and K) on diameter at breast height (DBH), height and biodiversity. Three transect lines according to altitudinal gradient were established to systematically allocate the plot. Total 45 samples having 20m×25m were established to collect the biophysical data and soil samples. DBH and height of trees were recorded and soil samples were carried out in the lab. The Shannon –Weiner Index, Simpson Index and Evenness Index were analyzed. Nitrogen (N), Phosphorous (P) and Potash (K) was analyzed using Kjeldahl, Olsen’s and Somers and Flame photometric methods respectively. The Pearson’s correlation was performed to show the relation of DBH, height and biodiversity indexes with N, P and K. Descriptive statistics showed that the highest Mean±SE DBH (cm) was 50.75±4.61 in altitude<200m while this was the least 34.92±1.35 cm in altitude 200-400 m. The highest value of Shannon –Weiner index was 0.95 at altitude of <200m and lowest value was 0.47 at altitude of 200-400m. R square values of DBH vs. Nitrogen% at 10-20 cm depth was 0.033. Similarly, R square value of DBH vs. Phosphorous was more about 0.102 and 0.323 at 0-10 and 10-20 cm depth respectively. This R square value of Height vs. Phosphorus was 0.024 and 0.117 respectively. R square of height vs. Potash was 0.034 and 0.001 at 0-10 and 10-20 cm depths respectively. F-test showed that the correlation between Soil nutrient (N, P, K) and tree structures (DBH and Height) was insignificant at 95% confidence level since the p>0.05. However, t-test showed that, the intercept used in the equation was significant at 95% confidence level. R square value of H’ and N% was 0.001 and 0.008 at 0-10 and 10-20 cm soil depth respectively. Similarly, the R square value of H' vs. P (kg/ha) was 0.38 and 0.42 at 0-10 and 10-20 cm soil depth respectively. Moreover, the R square value of H' vs. K (kg/ha) was 0.36 and 0.01 respectively. This research will be useful to understand the effect of soil nutrients on DBH, height and soil nutrient in the forest according to altitudinal gradient.
Abstract: This research was done to assess effect of soil nutrients (N, P and K) on diameter at breast height (DBH), height and biodiversity. Three transect lines according to altitudinal gradient were established to systematically allocate the plot. Total 45 samples having 20m×25m were established to collect the biophysical data and soil samples. DBH and he...
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