New and interesting diatoms from the Shimen Wetwalls,Yunnan Province,China.Ⅱ.The diatom genus Nupela Vyverman&Compère(Bacillariophyceae)

We detailed the valve morphology of five new species of diatom genus Nupela from wetwall communities in Yunnan Province,China,with light and scanning electron microscope.The five new species demonstrate great variability within the genus,as three of them are biraphid and two are monoraphid.In addition,variation was noted in the structure of internal proximal raphe ends,with some species having anchor-shaped ends and other species have hooked ends.The genus Nupela has grown considerably in 30years since it was first proposed,going from a monotypic genus to over 85 taxa.Diagnosis of the genus is based on the presence of an external covering over the areolae.We discussed the systematic placement of Nupela within the naviculoid diatoms.Yunnan Province appears to harbor many endemic diatom taxa,and many regions of the province have yet to be studied.

Gomphonema Ehrenberg species from the Yuntai Mountains,Henan Province,China

We report on eight species of the freshwater diatom genus Gomphonema from aquatic habitats from the Yuntai Mountains of Henan Province,China.This work represents the first detailed descriptions of the freshwater diatoms from this centrally-located province in China.Of the eight taxa considered,five are new to science and another is given a"cf."designation.Four of the eight species are similar in morphological features to other,"classical"species,with external areolar occlusions forming C-shaped openings.Another species is astigmate,and has distinct siliceous papillae located marginally on the exterior of the valves;this morphology has not been recognized previously for the genus.Two of the species have internal areolar and stigma occlusions.The diversity of morphological types of species in Gomphonema may relate to the ecosystems,with more diverse ecosystems harboring greater diversity of these morphological groups of Gomphonema.

Phycological Effects of Eutrophication with Fertilizers in Nike Lake, Nigeria

Agriculture around Nike lake uses fertilizers. Fertilizers are known to cause eutrophication of water bodies and associated algal blooms whose consequences may be deleterious to the environment and man. We investigated ex situ to assess the effect of the nutrients on the algal flora and show the impact of farm land runoffs on aquatic environment. The lake water was analysed for initial nitrogen, phosphorus and potassium;and algal content using standard methods. The fertilizer sources used by the farmers—NPK (20:10:10 and 15:15:15);urea and poultry drops, were used in the study to enrich the lake water in concentrations of 0.2, 0.4, 0.6, 1.0 and 2.0 g/L in three replicates respectively. A control was set up without the fertilizer sources and the set up was left on a laboratory bench and monitored for 36 days. Cyanobacteria (blue green algae), Chlorophyta (green algae) and Bacillariophyta (diatoms) were encountered and their population increased with time and increase in concentration of fertilizers. The following taxa were encountered—Gloeocapsa, Anabaena, Oscillatoria (blue-green algae);Chlorella, Chlamydomonas, Spirogyra, Closterium, Pediastrum, Ankistrodesmus, Selenastrum, Scenedesmus, Staurastrum (green algae);Pinnularia and Navicula (diatoms) some of which are notable bloom forming species.