Abstract: A comparative study of the biomass of zooplankton of four semi-intensive fish ponds found in the ecological area of Yaoundé in Cameroon was sampled for 9 months, which made it possible to evaluate the influence of the maintenance quality of the water bodies on their productivity. There were three ponds E1, E2, and E3 fertilized with organic and mineral matter, sampled from March to November 2012 on the one hand and on the other hand an experimental pond ET serving as a control, which was sampled from March to November 2014. ET was fertilized with mineral and organic matter and received particular attention during the first three months of breeding. The breeding method recommended in these ponds was the polyculture of Clarias gariepinus and Oreochromis niloticus. The samples were collected twice a month at 20 cm depth. Physico-chemical and biological analyses were measured using appropriate techniques. Zooplankton biomass remained very high in ET relative to E1, E2 and E3 (90% vs. 10%), creating an uneven profile in all water bodies. Minimum biomass values were 119 mg C / L in E1, 200 mg C / L in E2, 40 mg C / L in E3 and 781 mg C / L in ET; the maximum values being 748 mg C / L, 2643 mg C / L, 474 mg C / L and 67010 mg C / L in E1, E2, E3 and ET respectively. The largest contributors to this biomass were rotifers followed by Cladocerans in ET and E2 and Copepods followed by rotifers in E1 and E3. Food resources were thus limited in these last two water bodies compared to others. Abiotic and biological analyses indicate that these water bodies were oligomesotrophic (E1 and E3), mesotrophic (E2) and eutrophic (ET). ET under these conditions enabled the production of a satisfactory fish yield. It is therefore recommended that, fish farmers should improve the quality of maintenance of fish ponds which together with good fertilization will generate maximum productivity.Abstract: A comparative study of the biomass of zooplankton of four semi-intensive fish ponds found in the ecological area of Yaoundé in Cameroon was sampled for 9 months, which made it possible to evaluate the influence of the maintenance quality of the water bodies on their productivity. There were three ponds E1, E2, and E3 fertilized with organic and min...Show More
Abstract: In India, the bryophytes are represented by 2562 taxa (1636 mosses, 887 liverworts and 39 hornworts). They usually inhabit narrow ecological niches with preference for damp and shady conditions. In Himalayas the bryophytes are rich in diversity and well represented due to prevailing of high rainfall and humidity. Eastern Himalayas are richest in bryophyte flora. Bryophytes are of great ecological importance, they are Pioneer of the land plants and the first plants to grow and colonize the barren rocks and lands. In India, the bryophytes are represented by 2562 taxa (1636 mosses, 887 liverworts and 39 hornworts). Along the Mizoram roads 76 species of bryophytes distributed over 29 families have been identified and recorded by the authors. These bryophytes provide vital ecosystem services like soil formation, habitat modification and nutrient cycling and are useful in pollution detection and monitoring. The flavonoids and terpenoids contained in majority of them show various biological activities with considerable potential of chemical and pharmaceutical properties. Road side village people in Mizoram generally use these bryophytes as medicines, vegetable and for prevention of soil erosion. It has been assessed that during road development these flora will be impacted and that will have impact on community settled along the road. Effort has been made in this paper to assess the diversity of bryophytes along the road corridors so that proper planning can be done during road development to save this natural resource.Abstract: In India, the bryophytes are represented by 2562 taxa (1636 mosses, 887 liverworts and 39 hornworts). They usually inhabit narrow ecological niches with preference for damp and shady conditions. In Himalayas the bryophytes are rich in diversity and well represented due to prevailing of high rainfall and humidity. Eastern Himalayas are richest in br...Show More
