FLORISTIC VARIATIONS AND NUTRIENT STATUS OF PERI URBAN WETLANDS IN IBESIKPO ASUTAN LOCAL GOVERNMENT AREA AKWA IBOM STATE NIGERIA
TABLE OF CONTENTS
Pages
Declaration – – – – – – – – i
Certification – – – – – – – – ii
Dedication – – – – – – – – iii
Acknowledgements – – – – – – iv
Table of contents – – – – – – – v
List of tables – – – – – – – viii
Abstract – – – – – – – – ix
Chapter one:
1.0 Introduction
Back ground of study – – – – – 1
Aquatic macrophytes – – – – – – 3
Types of aquatic macrophytes – – – – 4
Plant nutrients – – – – – – – 7
Statement of problem – – – – – 8
Objective of the study – – – – – 9
Justification of study – – – – – – 9
Chapter two:
2.0 Review of related literatures
2.1 Macrophytes abundance and distribution within
different landscape – – – – – – 10
2.2 Physical and chemical habitat characteristics of
aquatic macrophytes – – – – – – 24
2.3 Uses of aquatic macrophytes – – – – 27
2.4 Nutrient functions and deficiency symptoms – – 32
Chapter three: Materials and methods
3.1 Soil sample collection – – – – – 48
3.2 Laboratory procedures for soil analysis – – – 48
3.2.1 Soil pH – – – – – – – 48
3.2.2 Determination of electric conductivity (EC) – – 49
3.2.3 Organic carbon content – – – – – 50
3.2.4 Total nitrogen – – – – – – 50
3.2.5 Exchangeable Bases – – – – – 52
3.2.6 Determination of Exchange Acidity (EA) – – 53
3.2.7 Effective Cation Exchange Capacities (ECEC) – 54
3.2.8 Base Saturation (BS) – – – – – 55
3.2.9 Particle Size Analysis – – – – – 55
3.2.10 Determination of Available Phosphorus – – 57
Chapter four:
4.1 Results – – – – – – – – 59
Chapter five:
5.1 Discussion – – – – – – – 66
5.2 Conclusion – – – – – – – 71
5.3 Recommendations – – – – – – 72
References – – – – – – – – 73
LIST OF TABLES
Pages
TABLE 1: Mean (±S.E) of vegetation characteristic
of selected wetlands. – – – – – – – 60
TABLE 2: Biodiversity status of studied wetlands. – – 62
TABLE 3: Mean (±S.E) of physico-chemical characteristics
of soils of wetlands. – – – – – – – 64
ABSTRACT
The understanding of the nutrient status of the vegetation had become a major concern for most ecologists over the last decades. Most ecologists had focused on the plant diversity and population dynamics without interest on major factors that can determine the existence of most species. Hence the floristic variations and nutrient status of a Peri-urban wetland in Ibesikpo Asutan L.G.A were determined. Water quality parameters such as: pH, conductivity, temperature, dissolved oxygen etc., were determined using standard methods. Density and frequency of species were equally enumerated using standard methods. Results obtained revealed that wetland 1 had up to 12 plant species, wetland 2 recorded 10 species, and then wetland 3 had 13 species. The most frequent species which was common to the wetland was Nymphea lotus, while the least frequent species include Comelina benghalensis, Calapogonium muconoides, Pandika involucrata, Asystasia gigantic, Legeneria breviflora, Anthonotha, macrophylla and Costus afer were found as less frequent species in the area. Nymphea lotus had a higher density value of 2080 st/ha in all three wetlands, while the least density value was characteristic of Chromolaena odorata in wetland 1 with a value of 250 st/ha. Organic matter was high in the three wetlands. Total nitrogen and other soil nutrients were equally high. Shannon Weiner index values ranged between 2.016 in wetland 3 up to 2.398 in wetland 3 while Simpson’s value ranged between 0.836 in wetland 2 up to 0.896 in wetland 3. The Sorenson’s matrix compacted revealed that wetland 1 and 2 were most similar with an index of 0.450, whereas wetland 1 and 3 were the least similar in terms of shared species attributes. The study therefore revealed from the results that the distribution of species in the three wetland studied is a function of the nutrient availability in these ecosystems. This will go a long way in the conservation and possible management of wetlands in the near future.
CHAPTER ONE
INTRODUCTION
1.1 Background of study
Macrophytes are the conspicuous plants that dominate wetlands, shallow lakes, and streams. Macroscopic flora includes the aquatic angiosperms (flowering plants), pteridophytes (ferns), and bryophytes (mosses, hornworts, and liverworts). Macrophytes may be floating, floating-leaved, submerged, or emergent (Sculthorpe, 1967), and may complete their life cycle in water (still and flowing) or on hydric soils (inundated and non-inundated).
Aquatic macrophytes are considered photosynthetic organisms of freshwater habitats, comprising vascular plants, aquatic bryophytes and macro algae, easily seen with the naked eye and are normally found growing in or on the surface of water, or where soils are flooded or saturated long enough. Aquatic macrophytes as primary producers and habitat providers are important component of river ecosystems.
They play an important role in the structure and functioning of freshwater ecosystems (Wetzel, 2001; Hrivnak et al., 2009; Tamire and Mengistou, 2012). The macrophytes serve as a base of aquatic food-chains, besides they also actively contribute to the promotion and maintenance of food webs and services in freshwater ecosystems (Scheffer and Jeppesen, 2007; Smith, 2011).
Aquatic macrophytes also act as important bioindicators of environmental conditions and long term ecological changes in water quality (Lacoul and Freedman, 2006; Solimini et al. 2006). The function of macrophytes in these ecosystems is related to their structural attributes like species composition, distribution, abundance and diversity which in turn relies on various environmental factors such as light, water, temperature, substrate composition, disturbance, competitive interactions, herbivory, epiphyte loading, water levels, quality of the lake water and sediment nutrients (Kaul et al., 1978; Pandit, 1984, 1992; Barko and Smart, 1986; Duarte et al., 1986; Lodge, 1991; Cronk and Fennessey, 2001; Wetzel, 2001; Capers, 2003; Pankhurst, 2005; Jaikumar et al., 2011; Siraj et al., 2011; Feldmann, 2012; Tamire and Mengistou, 2012). Apart from these, factors such as composition and properties of sediments also seem to have significant effect on the distribution of certain Macrophytic species (Dawson and Szoszkiewicz, 1999; Heegaard et al., 2001). Vegetative and clonal reproduction is considered to be the major mechanism for population growth and dispersal of macrophytes because sexual reproduction and genetic recombination are often subordinate strategies (Wetzel, 2001). The efficient reproduction strategies and good dispersal capabilities are the two factors that help some aquatic macrophytes to become cosmopolitan in distribution and display high levels of polymorphism and phenotypic plasticity in response to variations of environmental factors. (Sculthorpe, 1967; Barratsegretain, 1996; Santamaria, 2002).
FLORISTIC VARIATIONS AND NUTRIENT STATUS OF PERI URBAN WETLANDS IN IBESIKPO ASUTAN LOCAL GOVERNMENT AREA AKWA IBOM STATE NIGERIA
