Effects of sediment and water quality on the distribution and abundance of aquatic weeds of Jebba Lake, Nigeria

Nutritional factors affecting the occurrence and distribution of aquatic weeds were monitored on Jebba Lake between June 1999 and May 2001. The result showed that bottom sediments quality and lake water chemistry impact the aquatic weed growth and development directly while shoreline chemical parameters impact more on the terrestrial vegetation. Chemical variables in bottom sediments, which directly affected abundance of aquatic weeds during the wet season include total nitrogen (r = 0.54), magnesium (r = 0.52), and ECEC (r = 0.45). However, during the dry season, aquatic weed occurrence and distribution were positively affected by total nitrogen (r = 0.65), organic matter and organic carbon (r = 0.64), potassium (r = 0.54), calcium (r = 0.53) and ECEC (r = 0.52) and pH of the sediment (r = 0.50). During the wet period, very low positive correlation existed between the aquatic weed abundance and the assayed physico-chemical parameters of water. During the dry season, weed abundance on the lake was principally affected by phosphorus and total nitrogen (r = 0.47) and to a lesser extent by sodium (r = 0.45) and calcium (r = 0.42).   Key words: Aquatic ecosystem, macrophyte/weed, ecological interaction, plant nutrient, sediment qualit

Biological Control Efforts of Water hyacinth (Eichhornia crassipes (Mart.) Solm) on Kainji Lake, Nigeria

Biological control of water hyacinth (Eichhornia crassipes (Mart.) Solm) was monitored on Kainji Lake between 1995 and 1999. The two most important host specific natural enemies of water hyacinth (Neochetina eichhorniae and N. bruchi) were used and impacts of the weevils on water hyacinth were monitored on tri-monthly basis. The manual control initiated by the National Institute for Freshwater Fisheries Research (NIFFR) encouraged the fishermen to physically remove water hyacinth from their shores and open water. The lake hydrology, most especially during the drawdown period when the water volume is reduced tremendously, allows water hyacinth plants to be stranded by the bank of the lake thereby leading to massive destruction of the weed population and consequently the weevils population stability. The floristic composition of macrophyte intimately mixed with the water hyacinth was also monitored during the low and high water regimes. Among the prominent plant species found with water hyacinth included Echinochloa stagnina, Mimosa pigra, Polygonium senegalensis Polygonium lanigarium. Sesbania dalzelli, and Vosia cuspidata were found competing with the much favoured Echinochloa spp which serves as forage to livestock around the lake; However, no incidence of weevil attack was observed on any of the vegetation mixed with water hyacinth. Keywords: Biocontol, Kainji Lake, Water hyacinth, Weevils

Water hyacinth cover and hydrological pattern of Kainji Lake

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Landuse and Landcover Change Detection of Jebba Lake Basin Nigeria: Remote Sensing and GIS Approach

This study is focused on change detection on the Jebba Lake Basin between 1978 (five years before the darn was established) and 1995 (twelve years after the dam impoundment. It is evidently clear that one of the problems associated with dams anywhere in the world, is environmental degradation. Landsat MSS Landuse/landcover map of 1978 and Spot XS landuse/landcover map of 1995 was used to study the landuse/landcover changes of the Lake area between 1978 and 1995 - a period of 17 years. Ilwis for Academic, Arcview 3.0 and Idrisi 32 were used for geo-referencing, digitizing and map analysis respectively. The two main methods of change detection that were used were area calculations (trends, rates and proportion), and overlay for the nature and the location of the changes. The study revealed that about 77.41% of the basin area has been subjected to changes, while, 22.59% had not been subjected to any changes. Five new agricultural practices came into being after the construction of the dam, which include, livestock farming, irrigation agriculture, floodplain agriculture, forest plantation, and tree crop plantation. All these agricultural activities covered about 808.5529km2, that is, 40.14% of the basin area. Keywords: Landuse, GIS, Remote Sensing, Jebba Lak

Influence of Weed Control Methods on Viability and Vigour of Maize (Zea mays L.) Seeds

Weed control method of choice should achieve the objective of controlling weeds without sacrificing seed quality. The influence of Combination of mechanical method (slashing at 2, and 4 week intervals), and herbicide (pre-emergence and post emergence) for weed control in maize on seed quality (viability and vigour) of maize seeds were evaluated.. Field and laboratory experiments were conducted to investigate the influence of pre-emergence (Diuron 50% SC {N (3, 4-dichlorophenyl) N, N-dimethyl urea} and post-emergence (Atrazine 50FW-{6 chloro-N-methyl-N-(1-methylethyl) 1, 3, 5-triazine, 2, 4 diamine}) herbicides either alone, or in combination with slashing at two and four-week, on seed quality. Combination of pre-emergence herbicide and slashing 2-weeks after planting  slashing gave the highest viability (91.37%) and lowest conductivity value (2.79 µS/cm/g), whereas combination of post emergence herbicide and 4 week slashing gave the lowest viability (77.67%) and the highest conductivity value (15.71 µS/cm/g). In accelerated ageing test, combination of pre-emergence herbicide with either 2 week slashing, or 4 week slashing  WAP gave the highest viability (84%), whereas combination of post emergence herbicide with 2 week slashing gave the lowest viability (51.33%) and lowest germination rate index (10.37). Combination of pre-emergence herbicide and 2-week slashing is the best complementary option for weed control in maize seed crop. Keywords; pre-emergence, post-emergence herbicides,  seed physiology,  maize seed viabilit

A 5‑year audit of diagnostic gynaecologic laparoscopy under conscious sedation at the University College Hospital, Ibadan

Introduction: Diagnostic laparoscopy affords smaller incisions, shorter recovery time, and fewer complications. In developing countries, access is limited by cost, infrastructural deficit, and expertise. In a bid to reduce cost at our center, conscious sedation for diagnostic laparoscopy was introduced as far back as 1980. We present here a 5‑year audit of our outpatient diagnostic laparoscopy highlighting the various indications, findings, and complications observed. Methodology: A retrospective review of case files of patients who had diagnostic gynecological laparoscopy between 1st January 2011 and 31st December 2015. The retrieved case files had data extracted and analysed using the Statistical Package for Social Sciences version 20 (Chicago IL USA). Data was presented as simple percentages using tables and figures. Results: During the period, 1,329 outpatient gynecological procedures were performed with 207 diagnostic gynecologic laparoscopies (15.6%). Only 187 case notes were retrieved (retrieval rate of 90%). The mean age was 33.04 (±5.2) years, 84.5% (158) had post‑secondary education, and 69.0% (129) were nulliparous. Majority, 131 (70.0%), had laparoscopy and dye test, 26 (14.0%) had laparoscopy alone, and 30 (16.0%) had a combination of laparoscopy, dye test, and hysteroscopy. The commonest indications were secondary infertility (51.9%), primary infertility (24.1%), and chronic pelvic pain (11.2%). Common findings at laparoscopy were pelvic adhesions (53.5%), uterine fibroids (35.1%), and bilateral tubal blockage (30.3%). Normal findings were reported in only 19 patients (10.3%). Conclusion: Diagnostic laparoscopy under conscious sedation is cost‑effective and safe. It has very minimal complications when performed by skilled personnel. It is thus recommended for low resource settings with the view to avail low income patients the opportunity for endoscopic evaluation.Key words: Audit; conscious sedation; diagnostic laparoscopy; low income

Serum total IgG and tetanus specific IgG in Nigerian human immunodeficiency virus infected primigravidae and the cord blood of their babies at birth

Background: HIV infection affects millions of women and children, particularly in sub-Saharan Africa. Tetanus also causes significant maternal and neonatal morbidity and mortality in developing countries. Since the main effect of HIV is immunosuppression, there is potential for a negative influence the host immune response to tetanus in women with HIV.Objective: This case-control study evaluated the effect of HIV infection on maternal tetanus antibody production and neonatal tetanus antibody levels.Methods: Thirty registered primigravidae were recruited from the clinic;15 were HIV positive and 15 were HIV negative. Serum samples of maternal and cord blood were obtained from both groups at delivery. Maternal total IgG and cord blood tetanus-specific antibody were estimated by Enzyme Linked Immunosorbent Assay.Results: There was no significant difference in the total IgG level of HIV positive mothers compared with HIV negative mothers. No significant difference in the tetanus-specific IgG level in the cord blood of babies of HIV positive mothers compared with cord blood of babies of the HIV negative mothers.Conclusion: HIV infection did not significantly reduce total IgG production in Nigerian primigravidae. Tetanus-specific IgG levels were above protective levels in neonates of HIV positive mothers suggesting adequate protection.Keywords: Tetanus, Antibody, Pregnancy, Immunisation, HI

Utilization of some aquatic macrophytes in Nigeria in-land water bodies: a review

Aquatic vegetation is an essential component of the aquatic ecosystem with both positive and negative implications on the water body. Efforts are always made to curtail the excessive growth of aquatic plants in order to prevent them from becoming a nuisance in the ecosystem. One of the ways of solving such problem is the positive economic use of such plants. Utilization as a method of weed control within the aquatic ecosystem is considered to be one of the safest methods of weed control as this provides the riparian communities double advantages in terms of save environment and personal benefits of the plant. The flora diversity of freshwater and brackish environments posses a great potential to both man and higher animals alike. Due to this fact, this paper attempt to review the exploited and unexploited aquatic plants resources of many of our water bodies in Nigeria both economica/ly and socially, to the populace. Recommendations are also advanced for further studies that will enhance sound management of the resources for maximum benefits and sustainabilit

The prospects of duckweed culturing in alleviating poverty in Nigeria

Duckweed is the smallest of all flowering plants and the plant double its mass in less than 2 days under ideal environmental conditions. Dry matter of duckweed contains between 35-45% crude protein. Moreover, the introduction of the plant to feed mill industries as a source of protein and binder supplement for pelleted fish feeds makes it of economic value. Duckweed has great potential if cultivation is encouraged in Nigeria, as this will also provide a good employment opportunity for larger percentage of youth in the riparian communities. The thrust of this paper was to explore the possibility of introducing duckweed farming to the rural populace for alternative sources of income most especially, the fisher folks and other interested farmer

Performance of Typha australis cut at three different heights

The response of Typha australis to stem cut at three different heights was studied for four weeks. This was carried out in the field between August and September 2003. Matured Typha australis naturally occuring along the stream within the Institute Integrated Fish Pond Complex, New Bussa were randomly selected. The shoots were cut at 10cm, 20cm, and 30cm, above the soil level. The responses of the plant were assessed. Plant cut at 10cm showed re-growth for one week and later died, while those cut at 20cm and 30cm showed re-growth through out the period of experiment. Result showed previous height between 10cm and 20cm is significant (P>0.05) between 10cm and 30cm height re-growth rates. But plant cut at 20cm and 30cm showed no significant (P>0.05), in height. The results show the susceptibility of Typha australis to stem cut at 10cm or below. Typha australis cut at 10cm above soil level are not likely to surviva