The Effects of Uncertainty on Estimating the Relative Environmental Quality of Watersheds Across a Region

Landscape ecologists may be faced with ranking the relative environmental quality of watersheds across a region. The rankings would be based on measured or modeled variables with inherent sources of error. This paper examines the impact of data uncertainty on the ranking assigned to watersheds. The approach is Monte Carlo simulation in which the individual variables are considered to be estimated with uncertainty. The results show that watersheds in the best and the worst condition have rankings that are robust to uncertainty but intermediate watersheds may be difficult or impossible to assign to a rank. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect offcial Agency policy.     

EFFECTS OF A MULTISTRAIN BIOFERTILIZER AND PHOSPHORUS RATES ON NUTRITION AND GRAIN YIELD OF PADDY RICE ON A SANDY SOIL IN SOUTHERN VIETNAM

Field experiments during two successive rainy seasons were conducted in southern Vietnam to evaluate the effects of a commercial inoculant biofertilizer (‘BioGro’) and fused magnesium phosphate (FMP) fertilizer on yield and nitrogen (N) and phosphorus (P) nutrition of rice. Inoculation with BioGro containing a pseudomonad, two bacilli and a soil yeast significantly increased grain yield in the second season and straw yield in both seasons by 3–5%. The FMP fertilizer significantly increased grain yield from 1.72–2.33 t ha^?1 to 2.99–3.58 t ha^?1 along with total N and P accumulation at all rates in both cropping seasons. In the first season the difference in grain yield between BioGro treated and untreated plots was marginal but in the second season BioGro out-yielded the control at all the rates of added P. Overall, BioGro application did not compensate for low P fertilizer application to the same extent previously demonstrated for low N fertilizer applications.     

Adhesion and colonization properties of potentially probiotic Bacillus paralicheniformis strain FA6 isolated from grass carp intestine

Fisheries Science - As a prerequisite for probiotics to establish and settle in the host intestine, adhesion is an essential criterion for probiotic screening. However, adhesion of probiotics in...     

Laos' hydropower development and cross‐border power trade in the Lower Mekong Basin: A discourse analysis

Increasing demands for energy to boost the Mekong economies have attracted the keen interest of riparian countries for hydropower development. This is evidenced by extensive investment in hydropower projects across the region over the last few decades. Drawing on interviews with key stakeholders, including officials from Ministry of Energy and Mines, Ministry of Natural Resources and Environment, Ministry of Agriculture and Forestry, private sector actors, civil society organisations and academics, as well as secondary data from public and policy resources, this paper aims to examine how the government of Laos' (GoL) decisions in hydropower development are influenced by regional energy dynamics, and how these shape the country's future energy development. The paper argues that the GoL's decisions on hydropower development are highly dilemmatic, given the current limited institutional capacity in hydropower governance and the accelerating evolution of alternative energy in neighbouring countries. While uncertainty in power markets is recognised, this places greater pressure on new hydropower projects as to how much power could be sufficiently produced and exported. The paper calls for GoL's policy considerations on the development and planning of alternative energy to secure the sustainable and equitable use of water resources as stipulated in the 1995 Mekong Agreement.     

Contrastive nutrient leaching from two differently textured paddy soils as influenced by biochar addition

Journal of Soils and Sediments - The aims of the current study were to (1) examine the interactive effects of biochar addition and differently textured soils (clayey and sandy soils) on nutrient...     

Seed Development, Maturation and Storage Behaviour of Mimusops elengi L.

Mass maturity (end of the seed-filling phase) occurred at about 72 days after flowering (DAF) in developing seeds of Mimusops elengi, at which time seed moisture content had declined to about 55%. The onset of ability to germinate was detected at 56 DAF and seeds showed 98% germination by 84 DAF. Tolerance of desiccation to 10% moisture content was first detected at 70 DAF and was maximal by 84 DAF. Delaying collection by a further 14 days to 98 DAF, when fruits began to be shed, reduced seed viability, particularly for seeds first dried to 10% moisture content. Hence the best time for seed collection appears to be about 14 days before fruits shed. In a separate investigation with six different seed lots, desiccation below about 8–12% moisture content reduced viability (considerably in some lots). The viability of dry seeds (below about 10% moisture content) stored hermetically was reduced at cool temperatures (5 °C and below), and none survived storage at sub-zero temperatures. The results suggest that Mimusops elengi shows intermediate seed storage behaviour and that the optimal hermetic seed storage environment is about 10% moisture content at 10 °C, while short-term, moist, aerated storage at high (40%) moisture content is also feasible.     

The Endo-α(1,3)-Fucoidanase Mef2 Releases Uniquely Branched Oligosaccharides from Saccharina latissima Fucoidans

Fucoidans are complex bioactive sulfated fucosyl-polysaccharides primarily found in brown macroalgae. Endo-fucoidanases catalyze the specific hydrolysis of α-L-fucosyl linkages in fucoidans and can be utilized to tailor-make fucoidan oligosaccharides and elucidate new structural details of fucoidans. In this study, an endo-α(1,3)-fucoidanase encoding gene, Mef2, from the marine bacterium Muricauda eckloniae, was cloned, and the Mef2 protein was functionally characterized. Based on the primary sequence, Mef2 was suggested to belong to the glycosyl hydrolase family 107 (GH107) in the Carbohydrate Active enZyme database (CAZy). The Mef2 fucoidanase showed maximal activity at pH 8 and 35 °C, although it could tolerate temperatures up to 50 °C. Ca²⁺ was shown to increase the melting temperature from 38 to 44 °C and was furthermore required for optimal activity of Mef2. The substrate specificity of Mef2 was investigated, and Fourier transform infrared spectroscopy (FTIR) was used to determine the enzymatic activity (Units per μM enzyme: U_f/μM) of Mef2 on two structurally different fucoidans, showing an activity of 1.2 × 10⁻³ U_f/μM and 3.6 × 10⁻³ U_f/μM on fucoidans from Fucus evanescens and Saccharina latissima, respectively. Interestingly, Mef2 was identified as the first described fucoidanase active on fucoidans from S. latissima. The fucoidan oligosaccharides released by Mef2 consisted of a backbone of α(1,3)-linked fucosyl residues with unique and novel α(1,4)-linked fucosyl branches, not previously identified in fucoidans from S. latissima.     

Enrichment planting of native species for biodiversity conservation in a logged tree plantation in Vietnam

Decades of deforestation and over logging have created large expanses of degraded lands in many countries including Vietnam. Reforestation may offer one means of mitigating these processes of degradation while sustaining biodiversity conservation. However a lack of information regarding trees, in particular threatened tree species has been identified as an important limitation in being able to reforest for biodiversity conservation. In the current study, conducted in the Tan Phu “protection forest”, the investigation surrounds the feasibility of biodiversity restoration in a fast-growing plantation after logging. Twelve threatened and native species mainly belonging to the Dipterocarpaceae and Fabaceae families have been considered. Seedlings grown in a local nursery have been planted under the canopy of a 50 ha pioneer forest, with a distance of 5 m between plants and between rows. The experimental design consists of blocks, each one with a replication of a 16-tree plot for each species. Four years after plantation, the survival rate of seedlings is high (>70 %), except for Dipterocarpus costatus (<10 %). Growth shows possible inhibitions under a closed canopy but the mean annual increment is generally satisfactory. The early performance of the seedlings is promising to make this plantation a good example of biodiversity restoration. These results could enhance the reforestation efforts of forest managers and encourage them to use native tree species including threatened ones in order to restore a high level of biodiversity in tropical degraded forests.     

Water-soluble and lipid-soluble arsenic compounds in japanese flying squid Todarodes pacificus

Water-soluble and lipid-soluble arsenic compounds in Japanese flying squid Todarodes pacificus were analyzed. Regardless of the tissues, the major water-soluble arsenic compound was identified as arsenobetaine by LC/ESI-MS analysis, as reported for a number of marine animals. Lipid-soluble arsenic compounds were found at relatively high levels in liver and testis. LC/ESI-MS analysis of water-soluble arsenic compounds released from liver phospholipids by either chemical hydrolysis or phospholipase D hydrolysis demonstrated that the major arsenolipids are dimethylarsinic acid (DMA)-containing glycerophospholipid (phosphatidyldimethylarsinic acid) and DMA-containing sphingomyelin where the choline moiety of sphingomyelin is replaced by DMA. This is the first work to report the presence of DMA-containing phospholipids in marine invertebrates.