The role of Typha spp. on water loss and public health has been uncertained and relatively poorly reported in Hadejia Nguru wetlands. This study investigated the extent to which Typha spp. contributed to evapotranspir...The role of Typha spp. on water loss and public health has been uncertained and relatively poorly reported in Hadejia Nguru wetlands. This study investigated the extent to which Typha spp. contributed to evapotranspirative water loss and the level at which it provides suitable habitat for mosquito breeding. A comparative analysis between Typha swamp and open water was made to determine the evapotranspiration water loss and mosquito larva load accounted for by Typha swamp in the wetland. Maximum and minimum temperatures were measured and recorded daily for the months of January, March and June in 2013. Blaney-Criddle equation was used to estimate the evapotranspiration from Typha swamp (Site A) while piche evaporimeter was used to measure direct evaporation from the adjacent open water (Site B). Water samples were collected in Sites A and B using 100 ml beaker at random and the number of mosquito larvae in the sample was counted. T test was used to evaluate differences in water loss and larva load between open water and Typha swamp in the wetland. The findings revealed that there was no significant difference in water loss at p < 0.05 between Typha swamp and open water in the wetland. However, the Typha swamp was found to harbor more mosquito larvae than the open water at p < 0.05 which was considered a public health risk.展开更多
The removal efficiency of Cu and Zn from swine wastewater was evaluated as effected by three variables: the hydraulic retention time (HRT) (24, 48, 72 and 96 hours), two different plant species (Typha domingensis Pers...The removal efficiency of Cu and Zn from swine wastewater was evaluated as effected by three variables: the hydraulic retention time (HRT) (24, 48, 72 and 96 hours), two different plant species (Typha domingensis Pers. and Eleocharis cellulosa) and two different sizes of filter media (5 and 15 mm) using a horizontal sub-surface flow constructed wetland. From the results, a significant difference was observed in the removal efficiency of Cu and Zn with respect to different hydraulic retention times. The best results were obtained in the HRT of 96 hours for Zn where 96% removal of Zn with Typha domingensis Pers. specie with gravel of 15 mm (experimental unit 6) was achieved. For Cu, at 72 hours of HRT, the efficiency was nearly 100% in five of the six study units (1, 2, 3, 5 and 6). In contrast, in experimental unit 4 with gravel of 15 mm and without plants, only 86% Cu removal was achieved.展开更多
There are few studies on the size and changes in species composition over time for wetlands in South Africa. Techniques such as remote sensing have become popular in assisting the development of management plans due t...There are few studies on the size and changes in species composition over time for wetlands in South Africa. Techniques such as remote sensing have become popular in assisting the development of management plans due to their spatio-temporal advantages and easily reproducible vegetation and land cover maps. The Wakkerstroom wetland was examined using aerial photography to examine possible changes in the extent and Landsat imaging was used to map its vegetation communities. To assess the distribution of vegetation types on Wakkerstroom wetland, in situ recording of vegetation types and their GPS coordinates was conducted and a Random Forest model was used to predict vegetation types from Landsat pixel spectra across the wetland extent. As calculated from aerial photographs, the Wakkerstroom wetland has increased in extent by 0.483 km2 from 1938 to 2009. The <em>P. australis</em> population density increased significantly over time (r = 0.89), whereas the <em>T. capensis</em> population density had a strong negative correlation over time (r = -0.70). A strong negative relationship between <em>P. australis</em> and <em>T. capensis</em> existed (r = -0.88). A need exists to introduce a management tool that will create a greater mosaic of vegetation communities thus ensuring a greater bird, reptile, and amphibian diversity.展开更多
In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed...In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability.展开更多
以北京白河人工湿地再生水补水河段香蒲根为研究对象,采用16S r DNA克隆文库技术对香蒲根内生细菌群落多样性进行分析,得出该克隆文库包括4大类群细菌,最优势类群为变形杆菌门Proteobacteria,其中包括Gammaproteobacteria、Betaproteoba...以北京白河人工湿地再生水补水河段香蒲根为研究对象,采用16S r DNA克隆文库技术对香蒲根内生细菌群落多样性进行分析,得出该克隆文库包括4大类群细菌,最优势类群为变形杆菌门Proteobacteria,其中包括Gammaproteobacteria、Betaproteobacteria、Epsilonproteobacteria、Alphaproteobacteria;其次为厚壁菌门Firmicutes、疣微菌门Verrucomicrobia、拟杆菌门Bacteroidetes;另外还包括部分非培养未确定种属的细菌.结合研究区再生水排放口与湿地下游水质数据,得出TN、TP、NO3-去除率达到了42.15%、47.34%、28.56%,表明湿地对再生水中的TN、TP、NO3-具有明显去除机制,说明香蒲根内生细菌克隆文库中菌株与湿地氮、磷等生物地球循环关系密切.展开更多
文摘The role of Typha spp. on water loss and public health has been uncertained and relatively poorly reported in Hadejia Nguru wetlands. This study investigated the extent to which Typha spp. contributed to evapotranspirative water loss and the level at which it provides suitable habitat for mosquito breeding. A comparative analysis between Typha swamp and open water was made to determine the evapotranspiration water loss and mosquito larva load accounted for by Typha swamp in the wetland. Maximum and minimum temperatures were measured and recorded daily for the months of January, March and June in 2013. Blaney-Criddle equation was used to estimate the evapotranspiration from Typha swamp (Site A) while piche evaporimeter was used to measure direct evaporation from the adjacent open water (Site B). Water samples were collected in Sites A and B using 100 ml beaker at random and the number of mosquito larvae in the sample was counted. T test was used to evaluate differences in water loss and larva load between open water and Typha swamp in the wetland. The findings revealed that there was no significant difference in water loss at p < 0.05 between Typha swamp and open water in the wetland. However, the Typha swamp was found to harbor more mosquito larvae than the open water at p < 0.05 which was considered a public health risk.
文摘The removal efficiency of Cu and Zn from swine wastewater was evaluated as effected by three variables: the hydraulic retention time (HRT) (24, 48, 72 and 96 hours), two different plant species (Typha domingensis Pers. and Eleocharis cellulosa) and two different sizes of filter media (5 and 15 mm) using a horizontal sub-surface flow constructed wetland. From the results, a significant difference was observed in the removal efficiency of Cu and Zn with respect to different hydraulic retention times. The best results were obtained in the HRT of 96 hours for Zn where 96% removal of Zn with Typha domingensis Pers. specie with gravel of 15 mm (experimental unit 6) was achieved. For Cu, at 72 hours of HRT, the efficiency was nearly 100% in five of the six study units (1, 2, 3, 5 and 6). In contrast, in experimental unit 4 with gravel of 15 mm and without plants, only 86% Cu removal was achieved.
文摘There are few studies on the size and changes in species composition over time for wetlands in South Africa. Techniques such as remote sensing have become popular in assisting the development of management plans due to their spatio-temporal advantages and easily reproducible vegetation and land cover maps. The Wakkerstroom wetland was examined using aerial photography to examine possible changes in the extent and Landsat imaging was used to map its vegetation communities. To assess the distribution of vegetation types on Wakkerstroom wetland, in situ recording of vegetation types and their GPS coordinates was conducted and a Random Forest model was used to predict vegetation types from Landsat pixel spectra across the wetland extent. As calculated from aerial photographs, the Wakkerstroom wetland has increased in extent by 0.483 km2 from 1938 to 2009. The <em>P. australis</em> population density increased significantly over time (r = 0.89), whereas the <em>T. capensis</em> population density had a strong negative correlation over time (r = -0.70). A strong negative relationship between <em>P. australis</em> and <em>T. capensis</em> existed (r = -0.88). A need exists to introduce a management tool that will create a greater mosaic of vegetation communities thus ensuring a greater bird, reptile, and amphibian diversity.
文摘In Saint-Louis, Senegal, a constructed wetland with horizontal flow reed beds (FHa and FHb) has demonstrated significant efficacy in treating municipal wastewater. Analyzing various treatment stages, the system showed only a slight temperature variation, from an influent average of 26.3°C to an effluent of 24.7°C. Electrical conductivity decreased from 1331 mS/cm to 974.5 mS/cm post-primary treatment, with suspended solids (SS) dramatically reduced from 718.9 mg/L to 5.7 mg/L in the final effluent. Biochemical oxygen demand (BOD5) and chemical oxygen demand (COD) saw a notable decrease, from initial levels of 655.6 mg/L and 1240 mg/L to 2.3 mg/L and 71.3 mg/L, respectively. Nitrogenous compounds (N-TN) and phosphates () also decreased significantly, indicating the system’s nutrient removal capacity. Microbiological analysis revealed a reduction in fecal coliforms from 7.5 Ulog/100ml to 1.8 Ulog/100ml and a complete elimination of helminth eggs. The presence of Phragmites and Typha was instrumental in enhancing these reductions. The system’s compliance with the Senegalese standards for disposal into natural environments, WHO recommendations for unrestricted water reuse in irrigation, and the European legislation for water reuse was established. The effluent quality met the stringent criteria for various classes of agricultural reuse, illustrating the system’s potential for sustainable water management. This wetland model presents a robust solution for water-stressed regions, ensuring environmental protection while supporting agricultural needs. The study calls for ongoing research to further refine the system for optimal, reliable wastewater treatment and water resource sustainability.
文摘以北京白河人工湿地再生水补水河段香蒲根为研究对象,采用16S r DNA克隆文库技术对香蒲根内生细菌群落多样性进行分析,得出该克隆文库包括4大类群细菌,最优势类群为变形杆菌门Proteobacteria,其中包括Gammaproteobacteria、Betaproteobacteria、Epsilonproteobacteria、Alphaproteobacteria;其次为厚壁菌门Firmicutes、疣微菌门Verrucomicrobia、拟杆菌门Bacteroidetes;另外还包括部分非培养未确定种属的细菌.结合研究区再生水排放口与湿地下游水质数据,得出TN、TP、NO3-去除率达到了42.15%、47.34%、28.56%,表明湿地对再生水中的TN、TP、NO3-具有明显去除机制,说明香蒲根内生细菌克隆文库中菌株与湿地氮、磷等生物地球循环关系密切.
