CHAPTER ONE
INTRODUCTION
Pond water is considered as one of the major sources of water for fisheries
(Ekpenyong and Adeniyi, 1996; Mustapha, 2006; Chowdhury and Almamun, 2006). Pond
fishery is practiced in the north-eastern part of Nigeria on a large scale for better
augmentation of fish products and hence makes an interesting biotope for physico-chemical
and biological studies.
The anthropogenic inputs of complex mixtures from neighboring communities and
agricultural wastes, such as runoff of manures and fertilizers could lead to alteration of water
quality (Mustapha, 2006; Garget al., 2009). Of primary concern of these anthropogenic
activities is their effects on the water quality and aquatic life, hence water quality monitoring
is of immense importance in the use of water bodies for the management of fisheries
(Mustapha, 2006; Nweze, 2009a).
The practice of using cow dungand inorganic fertilizers to encourage algal growth in
fish ponds is wide spread in pisciculture in Nigeria (Nweze, 2009b). The algae serve as food
for zooplankton, fish fry, benthic vertebrate and other primary consumers that serve as food
for fish (Ezenwaji, 2004). Excess nutrients cause the water body to become choked with
organic substances exceeding the capacity of micro-organisms that recycle them. It ultimately
leads to eutrophication and encourages rapid growth or blooms of algae (Chukwu and
Odunze, 2006; Okebukola and Akpan, 2008; Akanet al., 2010).
Phytoplankton are of great ecological significance, since they comprise the major
portion of primary producers in the aquatic environment (Nweze,2003;Barinova et al.,2008,
Bellinger and Sigee, 2010). Human activities such as pond fertilization, fertilizers, pesticides
and herbicides application as cultural practices of farm management;obnoxious fishing
practices, effluent discharges, washing and bathing with detergent and soda soaps stimulate
growth of algae.Some of these are thecommonest sources of human-induced water pollution
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that bring about eutrophication, hypoxia, fish kill, disruption of food web and changes in the
community ecosystem (Mustapha, 2002, 2006; Krantz and Kifferstein, 2005; Garg et al.,
2006a, Chia et al., 2011a).
Algae can equally be harmful as some species aretoxins producing, in particular the
genera Microcystis,Oscillatoria,Aphanizomenon and Anabaena which cause serious
problemsin aquaculture (Nweze 2009b). Some harmful algae in Nigerian waters had been
discussed byKadiri (2000).
Man is currently harnessing phytoplankton forms for augmentation of food supply in
fish ponds, nitrogen fixation in rice growing, pharmaceuticals, direct in food and food
supplement, bioremediation and biomonitoring (USEPA, 1976; Borowitzka, 1995; Nweze,
2009a, andb; Kadiri, 2010). Knowledge of the algal diversity of the Nigerian aquatic
environment is pertinent to meeting up of such demands.
Phycological information on Nigerian lotic and lentic systems is still scarce. The
study of phytoplankton distribution in the Nigerian environmenthas been hindered by
taxonomic difficulties, and more importantly, inadequate facilities for the relevant studies
(Ekpenyong and Adeniyi, 1996; Opute, 2003; Kadiri, 2007).Despite these challenges, there is
the need to track the trends that threaten our aquatic ecosystems, specifically pond habitats,
and assess the influence of physico-chemical parameters on the algal diversity for stable
aquatic ecosystem.
1.1 AIM AND OBJECTIVES OF THE STUDY
The aims and objectives of the study are to access and determine the water quality and
algal diversity of fish ponds and Dam reservoir in Gesedaddo farms, Yola, Nigeria.
The specific objectives are to:
· Assess the water quality (physico-chemical parameters) of Gesedaddo farm’s fish
ponds (stocked and unstocked) and dam reservoir;
· Identify the algae present in the ponds and dam reservoir;
· Determine the influence of season on algal diversity in the ponds and dam reservoir.
· Identify indicators for monitoring the water quality of the ponds and dam reservoir;
· Correlate the physico-chemical parameters with algal population of the various ponds
and dam reservoir;
· Determine the trophic status of the ponds and the dam reservoir.
· Compare flora and physico-chemical (
