ABSTRACT

An assessment of vegetative composition and conservation status in Baturiya wetland in Jigawa state was carried out during the dry and rainy seasons of 2013/2014. Ecological variables such as soil bulk density, canopy cover and regeneration potential in different segments of the wetland were studied. Tree sample plots of 100 x 100m were located using a stratified sampling method, within each plot, three sub plots 0f 50m x 50m were randomly selected for identification and enumeration of species. Species diversity and equitability were worked out using the Shanon- Weiner diversity and equitability index. Human exploitation in the wetland was also evaluated. A total of 98 plant species were recorded which were distributed among 42 families. Family Fabaceae had the highest representation of 12.1% relative frequency and family Moringaceae being the least represented with 0.32% relative frequency. Azadirachta indica was the most dominant species followed by Hyphene thebaica, the least represented species were 16 among them were Mimosa Pigra, Mucuna prurient and Saba florida. There was generally high species diversity, sample plot 2 being the highest with 3.767 diversity index and evenness range of 0.664. Plot I had more herbs, plot II had more trees while plot III had only trees and shrubs. The level of association between the 3 sample plots was also high. The regeneration potential of the diversified species was generally poor. There was also low level of canopy cover above the species beneath. The soil bulk density was high which has a great implication for the regeneration and conservation of the various species encountered. Correlation matrix revealed a positive relationship between the regeneration potential and the canopy area, but there was a negative significant relationship between the regeneration potential and soil bulk density. The vegetation of the wetland is not uniform and is rich in species composition but there is high level of human

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CHAPTER ONE

1.0                                                                INTRODUCTION

The world and Africa in particular are facing serious challenges in the area of environmental degradation. The most important and prominent challenge in Africa today is desertification and climate change. The rate at which forest is being depleted today due to population growth, indiscriminate logging, construction purposes and farming is alarming (Adewale et al., 2002). Nigeria as a geographic entity has been blessed with a rich and unique array of ecosystem and great variety of natural resources. Its broad climatic variation have resulted in a distinct North-South gradation of ecological formation which in turn has a direct bearing on the diversity of flora and fauna supporting more than 1340 species of animals and about 4600 species of plants (Marguba,1996).

Wetlands are essential for hydrological and ecological process and they support a rich fauna and flora, they have different habitats and are places where different species of flora and fauna live. Wetlands act as a water filter, nutrients and sediments are abundant and that makes it possible for many species to live (HNWCP, 1999).

1.1         Definitions of Wetland

A Wetland is an area of land where the soil is saturated with moisture either permanently or seasonally such areas may also be covered partially or completely by shallow pools of water. Wetlands are also defined as transitional land between terrestrial and aquatic system that are characterized by certain water regimes, plant species and soil characteristics (Winter, 2013).

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Convention on wetlands of international importance (RAMSAR) defined wetland as areas of marsh, fen, peat land or water, whether natural or artificial, permanent or temporary with water that is static or flowing, fresh, brackish or salty including areas of marine water the depth of which at low tide does not exceeds six meters (6m).

Douglas (2009) defined wetland as geographic area with characteristics of both dry land and bodies of water. Wetland typically occur in low lying areas that receive fresh water at edges of lakes ponds streams, rivers or salt water from tides in coastal areas protected from waves. In wetlands water level called the water table is usually at above or just below the soil surface for enough time to restrict the growth of plant to those that are adapted to wet condition and promote the development of soil characteristic of wet environment (HNWCP, 1999).Wetlands are important to both human and wildlife, because they deliver a variety of beneficial ecosystems services such as supply of food, control of flood, cycling nutrients, filtering of water, removal of pollution and provision of habitats.

1.2         Distribution of Wet Lands

Wetlands are found on every continent (except Antarctica) and in climates ranging from tropic to the tundra. They occupy about six percent (6%) of the land surface of the world or approximately 890 million hectares (Douglas, 2009), they vary in location and size. Some wetlands cover a few million hectares while others are only a few thousand square meters (IUCN, 1980).

They are found in many countries such as the United Kingdom, Iraq, South Africa and the United states. Wetlands are the subject of conservation efforts and biodiversity action plan (NCF, 2010). Notable African wetlands indicated on the map of Africa

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are Logon flood plain in Cameroon, Amsuri Wetland of Ghana, Baobalon wetland in Gambia, Seri wetland in Mali and Hadejia- Nguru Wetlands of Nigeria.

Nigeria is uniquely bestowed with fresh water wetlands and the coasted saline wetlands. The fresh water wetland comprises the Imo River, Lake Chad, River, Niger Delta, Cross River, Niger River and Benue River, while the coastal saline wetlands consist of the Cross river estuary, Imo River, and the Niger River (Zaccheaus, 2012). Wetlands are among the world most productive environment. They produce numerous products for man and wildlife. They provide economic and good opportunities to observe wildlife and also educate people during field and school practical on Ecology. Indeed wetlands are considered as the most biologically diverse of all ecosystems (HNWCP, 1999).

Nigerian wetland resources are currently being threatened by certain anthropogenic and bio-geophysical factors. Notable among such factors are population pressure, overgrazing, logging, unprecedented land reclamation, construction of dams, transportation routes and other infrastructures (Anonymous, 2006). Conservation of habitat does not always mean that people are not allowed to live, work and make use of specific environment, it aims at making sure that people do not over-exploit the environment so that the environment can keep on self renewal and regenerating for present and future use. It is quite unfortunate that despite the importance of this resource and the consequences of its deterioration effort on its conservation has not been yielding positive result. This largely may be due to lack of up to date information on the extent, rate and nature of depletion (Akinyemi et al., 2001). Nigeria is a country richly endowed with both coastal and inland wetlands, which

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altogether cover about 3% of the country‟s land surface. These wetlands are of ecological, economic, social cultural, scientific and recreational significance.

Baturiya wetland is a part of Hadejia – Nguru wetlands which are located in the North eastern zone of Nigeria with an estimated area of 3500 square kilometers (HNWCP, 1999).The wetland currently support a population of about 1.5 million people engaged in various forms of livelihood such as fishing, farming and grazing. The area supports rich fisheries of which about 40 million Naira worth of fish is produced annually, according to 1989-90 estimate (Hollis et al., 1993).

In 1965, a Lion by name‟ Danjuma‟ was discovered in the wetland which was taken to the Emir of Hadejia and later in 1972 taken to Kano state zoological garden (Kabir, 2006).

1.3         Importance of Wetlands

An economically important plant locally called (Kabba‟ or Doum palm) Hyphaene thebaica yields over 40 million Naira from its products annually. The products are used for making ropes, mats, baskets and hats .They also provides employment for a good number of people within and outside the wetland (Becker, 1994).

The people produce large quantities of rice, wheat, cowpea and vegetables which are marketed to other p