Myxomycetes recorded from three lowland tropical forests in Vietnam

Abstract The first report of myxomycetes from Vietnam was in 2009 by van Hooff, who listed 23 species, including one (Cribraria tecta) new to science, from moist chamber cultures prepared with samples of dead leaves, lychee husks, woody twigs and herbaceous stems. Two other species, both new to science, were reported in a recent paper. The project reported herein investigated the occurrence of myxomycetes in moist chamber cultures prepared with samples of various types of dead plant material collected in three lowland tropical forests in Vietnam. These samples were randomly collected from Cuc Phuong, Bu Gia Map and Nam Cat Tien national parks in the late dry season or between the dry season and the rainy season during 2012 and 2013. From 360 moist chambers, 43 species of myxomycetes representing 19 genera were recorded. The most abundant species were Arcyria cinerea, Collaria arcyrionema, Cribraria microcarpa, Cribraria violacea, Perichaena chrysosperma and Perichaena depressa. The taxonomic composition of the assemblage of species associated with the three study areas was found to be similar to what has been reported from Laos, Myanmar and Thailand, the other regions of SE Asia for which comparable studies have been carried out. In brief, the present project added 32 new records of myxomycetes for Vietnam, increasing the total number of species known from the country to 57

Comparison of degradation kinetics of tannery wastewater treatment using a nonlinear model by salt-tolerant Nitrosomonas sp. and Nitrobacter sp.

Conventional biological treatment has been reported to be ineffective for pollutant removal in tannery wastewater due to high salinity. To overcome it, this work used salt-tolerant bacteria (STB) isolated from a membrane bioreactor to evaluate the organic and nutrient removal through a series of batch experiments. Compared with the control, the STB reactor enhanced the reduction of persistent organics by 11% based on the double exponential decay model. Besides, the removal of NH4+-N is 26% higher, satisfying the first-order decay model. The nitrification was inhibited entirely in control during 48 h, whilst the assimilation process involved 55% of total nitrogen removal. In the STB reactor, nitrification occurred after 12 h, resulting in significantly increased NO2--N and NO3--N concentrations according to the logistic function. Although nitrification was successfully activated, C/N ratios and free ammonia were identified as limiting factors for STB activity, requiring mitigation strategies in further studies