Authored by Algrient Nana Towa
In order to improve fish productivity, an essay on the evaluation of the comparative effect of chicken and pig manure on the composition and structure of Zooplankton was conducted at the Application and Research farm from the University of Dschang (LN: 5º44’-5 °36 and LE: 10º06’-9 ° 85’). For this purpose, 15 ponds (5.7 x 5.7 x 1m), three doses of 0 (control); 800 and 1000kg/ha of chicken manure as well as pig dung were used. At each of the randomly selected ponds was administered one of the fertilizer doses every 7 days. Each of the doses and type of fertilizer representing a treatment was repeated three times. The physicochemical characteristics of the water and the Zooplankton population were measured every 14 days. With respect to the physicochemical characteristics of water, the values of nitrites (7.92 ± 0.05mg/l), nitrates (8.03 ± 0.24mg/l), phosphates (4.68 ± 0, 05mg/l) were significantly (p <0.05) higher in ponds fertilized at 1000kg/ha pig dung, the lowest being obtained in the control treatment. For Zooplankton, the highest specific (64.51% of total species), generics (87.87% of total genera) and families (82.35% of total) Zooplanktonic abundances were obtained in ponds fertilized at the rate of 1000kg/ha of chicken manure. The species of rotifers were the most diverse survived those of cladocerans whatever the type or the dose of fertilizer. The use of the 1000kg/ha dose of chicken droppings makes sense for a large production of Zooplankton diversity.
In Africa and more specifically in Cameroon, the role of aquaculture in the economy remains marginal. In fact, aquaculture accounts for less than 0.1% of total fish inputs, despite the water surface area covering nearly 3.5 million hectares, spread over 4 major river basins MINEPIA [1]. It should be noted that commercial fish farming is 90% from fertilized ponds. However, one of the constraints of development of pond production is attributable to the fertilization technique associated with the mastery of the operation of the interspecific, intraspecific biodiversity of the living prey of the pond ecosystem.
Fertilization is an activity that makes it possible to optimize fish production by improving the physicochemical parameters of water and the densities of Zooplankton organisms [2], which are the living prey for the most fishes. Zooplankton is by its specific diversity and nutritional value the best fish about the plasticity of the diet of fish species. Several studies have been carried out on the fertilization of ponds from animal waste [3-5], at different doses. But none of this work has focused on studying the diversity of Zooplankton populations.
The objective of this work is to contribute to the improvement of the production of Zooplankton intended for larval feeding through a better fertilization. More specifically, the aim is to evaluate the effect of pig manure doses on:
• The physicochemical characteristics of water
• The richness and distribution of Zooplankton populations
Area and period of the study
The trial was conducted from May 15 to November 15, 2016 at the Dschang University Applied Research Farm (FAR) (LN: 5° 44’-5° 36’ and LE: 10° 06’ -9° 85’, altitude: 1392-1396m) in the Sudano- Guinean agro-ecological zone characterized by a short dry season (mid-November to mid-March) and a long rainy season (mid-March to mid-March) November). The annual rainfall varies between 1500 and 2000mm and the temperatures oscillate between 14 °C (July- August) and 25 °C (February).Fertilizer
The slurry and droppings used in hens came from a pork farm and egg layer layers fed a feed (feed). A sample of each fertilizer was taken to determine the total dry matter, nitrogen and phosphorus concentration. The average values of the characteristics of the droppings were: dry matter (80.2±3.33%), total nitrogen (2±0.14%) and total phosphorus (1.5±0.06%) and those of pig slurry: dry matter (30.5±2.21%), total nitrogen (33±1.11%), total phosphorus (9±2.30%).
Exp
erimental ponds
The test was carried out in 15 identical by-pass ponds (5.7 x 5.7
x 1m and a water exchange rate of 0.05 l/s). The 15 ponds were fed
in water from an artificial lake located 100m away. A 1.5mm mesh
net was attached to the feed pipe of each pond to prevent intrusion
of fish from the artificial lake.Conduct of the test and data collection
At each randomly selected pond, one of the 0kg/ha (control), 800; 1000kg/ha for both chicken manure and pig dung (weighed with a 0.1g precision electronic balance) corresponding to T0, F800, F1000, L800 and L1000, respectively. Fertilization was done every 7 days on the surface of each pond according to Lacroix (2004).Sampling
The determination of the physicochemical characteristics of the water was carried out parallel to that of Zooplankton every 14 days between 6 and 8 o’clock in the morning according to Agadjihouédé et al. [6] Dakwen et al. [7]. The sampling of Zooplankton was carried out at twenty different points of the water column of each pond using a calibrated polyethylene container of 1 liter capacity, ie a total volume of 20 liters/pond filtered by means of a plankton screen of 40μm mesh. A volume of 350ml Zooplankton concentrate was recovered, fixed by addition of 5% formalin (¼ volume of the concentrated sample) and stored in the plastic bottles for quantitative and qualitative analyzes.Determination of the physicochemical characteristics of water
a. The transparency of the dry disk, temperature, pH, dissolved oxygen and electrical conductivity were directly measured in the field with the help of a weighed dry disk and attached to a graduated rope, Thermo-Conductivity meter, Thermo pH-meter, pH meter, thermo-oximeter and thermo-conductivity meter brand HANNA.b. Total nitrite, nitrate and phosphate measurements were carried out by spectrophotometry (HACH DR/2000 spectrophotometer) using Alpha techniques Greenberg [8].
Determination of Zooplanktonic characteristics
Two types of analysis were carried out namely: qualitative analysis and quantitative analysis.To read more about this article...Oceanography & Marine biology
Please follow the URL to access more information about this article
https://irispublishers.com/aomb/fulltext/influence-of-types-and-doses-of-fertilizer-on-the-physicochemical-characteristics-of-water.ID.000516.php
To read more about our journals....Iris Publishers
No comments:
Post a Comment