17α-Ethinylestradiol in Lakes of Hanoi and its effect on seed germination

Abstract

The lakes of Hanoi are important water resources for urban agriculture. The concentrations of 17α-ethinylestradiol in the water of three major lakes were found to range from 0.1 to 9.1?ng/L, peaking during the rainy season. Effects at levels from 1?ng/L to 1?µg/L on the germination of mung bean (Vigna radiata) and bok choy (Brassica rapa) were studied. Soaking the seeds in solutions containing 17α-ethinylestradiol at 10?ng/L and higher increased the germination rate of mung bean but not of bok choy. For the latter, irrigation after sowing with solutions containing 17α-ethinylestradiol at 10?ng/L and higher accelerated germination.

Abbreviations: MNRE: Ministry of Natural Resources and Environment; PE₆₀: Population equivalent; USGS: U.S. Geological Survey; SPE: Solid phase extraction; EDTA: Disodium ethylenediaminetetraacetate; HPLC: High performance liquid chromatography; ELISA: Enzyme-linked immunosorbent assay; DOM: Dissolved organic matter; EEQ: Estradiol equivalent     

Factors affecting the interval between clutches in the hermit crab <Emphasis Type="Italic">Pagurus nigrivittatus</Emphasis>

Interval between reproductive events is an important factor for iteroparous animals because it determines the number of clutches throughout life. This study examined whether female size, clutch size, shell size and prenuptial molting affected the clutch interval in the hermit crab Pagurus nigrivittatus. Precopulatory guarding pairs of P. nigrivittatus were sampled in the field and kept in the laboratory until the female extruded eggs. The clutch interval of each female was assessed as one of two types of relatively “short” and “long” intervals by checking whether the guarded female had eggs and/or egg cases from the preceding brood or not when the guarding pair was collected. The clutch interval was longer in females with prenuptial molting than those without molting and these females usually grew larger at the prenuptial molt. This suggests that female P. nigrivittatus with a long interval might allocate energy into growth at the expense of the number of clutches during the current reproductive season. The allocation to growth is theoretically predicted to decrease with female size. Gastropod shell size is also known to affect the reproductive activity in hermit crabs. However, female size did not significantly affect the clutch interval in P. nigrivittatus, and the effect of gastropod shell size on clutch interval was not consistent with previous empirical studies. These results may be caused by differences in the gastropod species of shell occupied by the females of P. nigrivittatus.     

Fate of metals contained in waste electrical and electronic equipment in a municipal waste treatment process

In Japan, waste electrical and electronic equipment (WEEE) that is not covered by the recycling laws are treated as municipal solid waste. A part of common metals are recovered during the treatment; however, other metals are rarely recovered and their destinations are not clear. This study investigated the distribution ratios and substance flows of 55 metals contained in WEEE during municipal waste treatment using shredding and separation techniques at a Japanese municipal waste treatment plant. The results revealed that more than half of Cu and most of Al contained in WEEE end up in landfills or dissipate under the current municipal waste treatment system. Among the other metals contained in WEEE, at least 70% of the mass was distributed to the small-grain fraction through the shredding and separation and is to be landfilled. Most kinds of metals were concentrated several fold in the small-grain fraction through the process and therefore the small-grain fraction may be a next target for recovery of metals in terms of both metal content and amount. Separate collection and pre-sorting of small digital products can work as effective way for reducing precious metals and less common metals to be landfilled to some extent; however, much of the total masses of those metals would still end up in landfills and it is also important to consider how to recover and utilize metals contained in other WEEE such as audio/video equipment.     

Modeling the Production and Uses of Biological Resources from the Viewpoint of Energy Flow in a Rural Village in Sichuan,China

This study aimed at clarifying the impact of deforestation and afforestation on the quality of life in a village in Sichuan Province, China. We devised a conceptual model of bioresource production and use based on quantified energy flow. The basic structure of the model has three sectors: production, use, and externals. We developed comprehensive methodology to quantify the model. Bioresource use per person in 1997 was 3.7 GJ for food, 10.2 GJ for fodder, 0.2–0.4 GJ for building material, 12.8 GJ for fuel, and 1.8 GJ for fertilizer, totaling 28.6–28.8 GJ.We used four environmental indicators to evaluate bioresource production and use: a biological productivity indicator, a use-efficiency indicator, a supply–demand balance indicator, and a self-sufficiency indicator. Use of these indicators showed that supply-demand balance of fuel was dramatically improved from 30% to 85% by afforestation, but 99% of bioresource use still depends on domestic products. Thus, it is necessary to improve biological productivity and promote the efficient use of bioresources to achieve sustainable living in the area. Massive deforestation in the 1950s caused a direct shortage of building material and fuel wood. The shortage of wood led to a stagnation in the rebuilding of houses, and fuel wood was substituted with crop residues. Because crop residues had been used for fertilizer and fodder, their use as fuel caused a shortage of fertilizer and fodder. This was an indirect impact of deforestation on peoples quality of life.     

Degradation of dibromophenols by UV irradiation

We examined the degradation of dibromophenols （DBPs）, i.e. 2,4-DBP, 2,6-DBP and 3,5-DBP by ultraviolet （UV） irradiation and estimated the relationship between degradability and molecular orbital properties of each dibromopbenol. The removal of DBPs under a UV lamp system was successfully performed in an aqueous solution. After 5 min of irradiation, the initial DBPs concentration of 20 mg/L was decreased to below 1 mg/L, and about 60% of bromide ion was released. A decrease in the concentration of dissolved organic carbon （DOC） suggested the mineralization of DBPs, The mineralization may occur after release of bromide ions because the decrease of DOC was slower than the release of bromide ions. The degradability of 3,5-DBP was slightly lower than 2,6-DBP and 2,4-DBE Molecular orbital calculation suggested that the electrophilic frontier density and the highest occupied molecular orbital （HOMO） energy may be related to the degradability of DBPs.     

The cost of stratospheric climate engineering revisited

Stratospheric aerosol injection (SAI) has been receiving increasing attention as a possible option for climate engineering. Its direct cost is perceived to be low, which has implications for international governance of this emerging technology. Here, we critically synthesize previous estimates of the underlying parameters and examine the total costs of SAI. It is evident that there have been inconsistencies in some assumptions and the application of overly optimistic parameter values in previous studies, which have led to an overall underestimation of the cost of aircraft-based SAI with sulfate aerosols. The annual cost of SAI to achieve cooling of 2 W/m² could reach US$10 billion with newly designed aircraft, which contrasts with the oft-quoted estimate of “a few billion dollars.” If existing aircraft were used, the cost would be expected to increase further. An SAI operation would be a large-scale engineering undertaking, possibly requiring a fleet of approximately 1,000 aircraft, because of the required high altitude of the injection. Therefore, because of its significance, a more thorough investigation of the engineering aspects of SAI and the associated uncertainties is warranted.     

Mechanical behavior of inert waste landfills under seismic condition

Journal of Material Cycles and Waste Management - Mechanical properties and slope stability of inert waste landfills under seismic condition were studied with three different approaches: in-situ...     

Effects of adding slags on strength and leaching properties of soft soil

Journal of Material Cycles and Waste Management - Dredged soils are typically mixed with additives to improve their mechanical properties and reduce the risks of leaching toxic elements. An...