Mayfly (Insecta: Ephemeroptera) community structure as an indicator of the ecological status of a stream in the Niger Delta area of Nigeria.

نویسندگان

  • Francis O Arimoro
  • Wilhelmine J Muller
چکیده

Ephemeroptera is an important group of insects used in the bioassessment and monitoring of freshwater bodies worldwide because of their relative abundance in a wide variety of substrates and their increasing chances of detecting pollution impacts. In this study, their faunistic composition and spatiotemporal variations in density and diversity in River Orogodo (Southern Nigeria) was investigated at five ecologically distinct stations over a 12-month period. The mayfly nymph community responses to environmental variables were evaluated by means of biological measures and multivariate analysis (redundancy analysis [RDA]). Thirteen morphologically distinct taxa belonging to six families were identified. The dominant taxa were Afrobaetodes pusillus (23.1%), Baetis sp. (13.7%), and Caenis cibaria (11.4%). The density of Ephemeroptera differed significantly (p < 0.05) both in space and time. Diversity was influenced by substrate heterogeneity which in turn was influenced by catchment processes such as flooding and anthropogenic activities especially abattoir effluent. Based on the RDA ordination and relative abundance data, Baetis sp. dominated at impacted stations while a more equitable distribution of species were observed in less disturbed sites. Water velocity, canopy cover, nature of bottom sediments, and the amount of dissolved oxygen also accounted for the variations in Ephemeroptera densities at the different stations. Shannon diversity, taxa richness, and evenness were lowest in station 3 (the abattoir discharge site).

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Spatial distribution and seasonal changes of mayflies (Insecta, Ephemeroptera) in a Western Balkan peat bog

Peat bogs are unique wetland ecosystems of high conservation value all over the world, yet data on the macroinvertebrates (including mayfly assemblages) in these habitats are still scarce. Over the course of one growing season, mayfly assemblages were sampled each month, along with other macroinvertebrates, in the largest and oldest Croatian peat bog and an adjacent stream. In total, ten mayfly...

متن کامل

Occurrence and Distribution of Chrysene and its Derivatives in Crude Oils and Source Rock Extracts from Niger Delta, Nigeria

Crude oils and source rocks from the northern and offshore Niger Delta basin, Nigeria, have been characterized by gas chromatography-mass spectrometry in terms of their origin and thermal maturity based on the distribution of chrysene and its derivatives. The crude oils and source rocks were characterized by the dominance of chrysene over benzo[a]anthracene. 3-methylchrysene predominated over o...

متن کامل

An Investigation into Credit Receipt and Enterprise Performance among Small Scale Agro Based Enterprises in the Niger Delta Region of Nigeria

The study was designed to analyze credit receipt and enterprise performance by small scale agro based enterprises in the Niger Delta region of Nigeria. A multistage sampling technique was adopted in selecting 264 agro based enterprises and 96 agro based enterprises that accessed informal and formal credit respectively. The Heckman model was used to examine the factors affecting amount of inform...

متن کامل

Agro-Economic Comparison of the Achievements of Fadama III Agricultural Enterprises in the Niger Delta Area of Nigeria: Task-Target Performance Approaches

The study addressed the economic comparison of the achievements of Fadama III agricultural enterprises in the Niger Delta Area of Nigeria using task-target performance approaches. It aimed at identifying the indicators, tasks and targets and achievement of Fadama III. Some materials used were secondary information collected from the various Fadama III project offices. Simple random sampling tec...

متن کامل

The Impact of Rural-Urban Migration on Poultry Production in the Niger Delta Region, Nigeria

This study was conducted to reveal the impact of rural-urban migration on broiler production in the Niger Delta Region of Nigeria. Data were collected from 795 household heads and farmers/managers/supervisors of 25 selected broiler farms in the study area. Descriptive statistics and multiple regression analysis was utilized to analyze the data. Able bodied young men constituted most of the rura...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Environmental monitoring and assessment

دوره 166 1-4  شماره 

صفحات  -

تاریخ انتشار 2010