The analyses of water from four tributaries of Ikpa River: Afaha Nsai Stream (ANS), Ikot Ekpuk Stream (IES), Afaha Itam Stream(AIS) and Nduetong Stream (NDS) in International Telecommunication Union (ITU) Local Gover...The analyses of water from four tributaries of Ikpa River: Afaha Nsai Stream (ANS), Ikot Ekpuk Stream (IES), Afaha Itam Stream(AIS) and Nduetong Stream (NDS) in International Telecommunication Union (ITU) Local Government Area of Akawa Ibom State in Nigeria were carried out using standard analytical procedures. The parameters investigated were temperature(Temp.), hydrogen ion concentration(pH), total suspended solids (TSS), total dissolved solids (TDS), dissolved oxygen (DO) and biochemical oxygen demand (BOD). Correlation analysis carried out between pairs of variables showed that only the correlation coefficients between TDS and DO in ANS( p <0.05); Temp. and TDS in IES ( p <0.05) and between Temp. and TDS in AIS ( p <0.01) were significant. None of the pairs of the variables in NDS showed any significant correlation. The coefficients of variation for the parameters were also computed and used in determining their stability in the water. The possible effects of these variables on each other and on the aquatic ecosystem were discussed.展开更多
This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities o...This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities of soil animals decreased with organophosphorus pesticide pollution degree increasing. The species of soil animals decreased with average and rare population mainly decreasing, while the amount change was associated with that of the dominant population of Acarina, Collembola and Nematoda. Toxicity experiment demonstrated that the respiration intensity of soil animal was restrained obviously by pesticide pollution. After observation of SEM, the effect of pesticide pollution on the earthworm (\%Pheretima robusta)\% stomach intestinal mucosa damage has been observed, which showed the pesticide contamination may damage the earthworms bodies. Ulcerous focus and perforation on stomach mucosa were usually seen. The stomach microvilli appeared atrophic and disordered especially in the bodies of these earthworms growing in seriously polluted soil, bad atrophic phenomena were seen not only on the stomach mucosa microvilli but also on the cilia of the intestinal mucosa which appeared swollen as a spheroid. Under TEM, RER and Golgi compound dilatation, chondrisome swell and ridge disappearance were observed on cells of stomach epithelium mucosa of \%P.robusta\% collected from heavy polluted area. By calculation, the safety concentration of earthworm in methamidophos pesticide is 0\^2517 ml/L.展开更多
The association of pollutants (nutrients, heavy metals and organic compounds) with colloidal and suspended particle matter(SPM) plays a dominant role in determining their transport, fate, biogeochemistry, bioavailabil...The association of pollutants (nutrients, heavy metals and organic compounds) with colloidal and suspended particle matter(SPM) plays a dominant role in determining their transport, fate, biogeochemistry, bioavailability and toxicity in natural waters. A scheme for the fractionation and composition of colloidal and suspended particulate matter from river waters has been tested. Sieving, continuous flow centrifugation and tangential flow filtration were used to collect gram amounts of colloidal and particulate matters. The separation scheme was able to process large samples(100L), within reasonable times(1 day) and the apparatus was portable. The aquatic colloid was also separated with high resolution, and sized using sedimentation field\|flow fractionation technique. The mass\|based particle size distribution for the river water sample showed a broad size distribution between 0\^05 and 0\^4 μm with the maximum around 0\^14 μm. There was a systematic increase in the content of organic carbon, Mg, Ca, Na, Cu and Zn with decreasing particle size, highlighting the importance of the colloidal(<1 μm) fraction.展开更多
文摘The analyses of water from four tributaries of Ikpa River: Afaha Nsai Stream (ANS), Ikot Ekpuk Stream (IES), Afaha Itam Stream(AIS) and Nduetong Stream (NDS) in International Telecommunication Union (ITU) Local Government Area of Akawa Ibom State in Nigeria were carried out using standard analytical procedures. The parameters investigated were temperature(Temp.), hydrogen ion concentration(pH), total suspended solids (TSS), total dissolved solids (TDS), dissolved oxygen (DO) and biochemical oxygen demand (BOD). Correlation analysis carried out between pairs of variables showed that only the correlation coefficients between TDS and DO in ANS( p <0.05); Temp. and TDS in IES ( p <0.05) and between Temp. and TDS in AIS ( p <0.01) were significant. None of the pairs of the variables in NDS showed any significant correlation. The coefficients of variation for the parameters were also computed and used in determining their stability in the water. The possible effects of these variables on each other and on the aquatic ecosystem were discussed.
文摘This paper studied the change in soil animal community in contaminated and irrigated area by organophosphorus pesticide waste water and its mechanism was discussed. The results showed that the species and quantities of soil animals decreased with organophosphorus pesticide pollution degree increasing. The species of soil animals decreased with average and rare population mainly decreasing, while the amount change was associated with that of the dominant population of Acarina, Collembola and Nematoda. Toxicity experiment demonstrated that the respiration intensity of soil animal was restrained obviously by pesticide pollution. After observation of SEM, the effect of pesticide pollution on the earthworm (\%Pheretima robusta)\% stomach intestinal mucosa damage has been observed, which showed the pesticide contamination may damage the earthworms bodies. Ulcerous focus and perforation on stomach mucosa were usually seen. The stomach microvilli appeared atrophic and disordered especially in the bodies of these earthworms growing in seriously polluted soil, bad atrophic phenomena were seen not only on the stomach mucosa microvilli but also on the cilia of the intestinal mucosa which appeared swollen as a spheroid. Under TEM, RER and Golgi compound dilatation, chondrisome swell and ridge disappearance were observed on cells of stomach epithelium mucosa of \%P.robusta\% collected from heavy polluted area. By calculation, the safety concentration of earthworm in methamidophos pesticide is 0\^2517 ml/L.
文摘The association of pollutants (nutrients, heavy metals and organic compounds) with colloidal and suspended particle matter(SPM) plays a dominant role in determining their transport, fate, biogeochemistry, bioavailability and toxicity in natural waters. A scheme for the fractionation and composition of colloidal and suspended particulate matter from river waters has been tested. Sieving, continuous flow centrifugation and tangential flow filtration were used to collect gram amounts of colloidal and particulate matters. The separation scheme was able to process large samples(100L), within reasonable times(1 day) and the apparatus was portable. The aquatic colloid was also separated with high resolution, and sized using sedimentation field\|flow fractionation technique. The mass\|based particle size distribution for the river water sample showed a broad size distribution between 0\^05 and 0\^4 μm with the maximum around 0\^14 μm. There was a systematic increase in the content of organic carbon, Mg, Ca, Na, Cu and Zn with decreasing particle size, highlighting the importance of the colloidal(<1 μm) fraction.
