Assessing the extinction risk of insular,understudied marine species

Hydrothermal vents are rare deep-sea oases that house faunal assemblages with a similar density of life as coral reefs. Only approximately 600 of these hotspots are known worldwide, most only one-third of a football field in size. With advancing development of the deep-sea mining industry, there is an urgent need to protect these unique, insular ecosystems and their specialist endemic faunas. We applied the IUCN (International Union for the Conservation of Nature) Red List criteria to assess the extinction risk of vent-endemic molluscs with varying exposure to potential deep-sea mining. We assessed 31 species from three key areas under different regulatory frameworks in the Indian, West Pacific, and Southern Oceans. Three vent mollusc species were also examined as case studies of different threat contexts (protected or not from potential mining) to explore the interaction of local regulatory frameworks and IUCN Red List category assignment. We found that these assessments were robust even when there was some uncertainty in the total range of individual species, allowing assessment of species that have only recently been named and described. For vent-endemic species, regulatory changes to area-based management can have a greater impact on IUCN Red List assessment outcomes than incorporating additional data about species distributions. Our approach revealed the most useful IUCN Red List criteria for vent-endemic species: criteria B and D2. This approach, combining regulatory framework and distribution, has the potential to rapidly gauge assessment outcomes for species in insular systems worldwide.     

液/固相单一离子吸附体系的动力学预测模型

对四种液/固相单一离子吸附体系的动力学研究结果表明:吸附速率不仅随时间变化,也与起始离子浓度(C0)和吸附剂浓度(W0)有关;Lagergren准二级方程在给定的起始离子浓度及吸附剂浓度下具有很高的模拟精确度,但其参数随起始离子浓度和吸附剂浓度的变化而变化,且无法确定其间的函数关系;结合四组分离子吸附模型,提出了新的动力学方程,实验结果表明,新方程具有较高的模拟精确度,其参数与C0和W0具有相对稳定的函数关系,可作为液/同相单一离子吸附体系中给定C0,W0条件下吸附动力学过程的预测模型.     

Extinction rate of discovered and undiscovered plants in Singapore

Extinction is a key issue in the assessment of global biodiversity. However, many extinction rate measures do not account for species that went extinct before they could be discovered. The highly developed island city–state of Singapore has one of the best-documented tropical floras in the world. This allowed us to estimate the total rate of floristic extinctions in Singapore since 1822 after accounting for sampling effort and crypto extinctions by collating herbaria records. Our database comprised 34,224 specimens from 2076 native species, of which 464 species (22%) were considered nationally extinct. We assumed that undiscovered species had the same annual per-species extinction rates as discovered species and that no undiscovered species remained extant. With classical and Bayesian algorithms, we estimated that 304 (95% confidence interval, 213–414) and 412 (95% credible interval, 313–534) additional species went extinct before they could be discovered, respectively; corresponding total extinction rate estimates were 32% and 35% (range 30–38%). We detected violations of our 2 assumptions that could cause our extinction estimates, particularly the absolute numbers, to be biased downward. Thus, our estimates should be treated as lower bounds. Our results illustrate the possible magnitudes of plant extirpations that can be expected in the tropics as development continues.     

浅析绿色制造的战略环境评价

绿色制造的战略环境评价是实现可持续发展的关键技术 ,是协调环境与社会经济发展的重要手段。它要求在绿色制造初期———绿色设计阶段就考虑整个制造过程的环境影响 ,从决策源头上控制环境污染的产生和生态环境的破坏。本文从绿色制造的广义内涵入手 ,分析了绿色制造战略环境评价的理论基础和综合集成特性 ,并提出了战略环境评价的指标体系和综合集成评价方法。     

Subarachnoid cyst with hydrocephalus–a complication of mid-trimester amniocentesis

We report a child with a subarachnoid cyst with hydrocephalus following a mid-trimester amniocentesis. Although fetal trauma is a rare complication, it is important to stress the need to perform amniocentesis under ultrasound control. Children with neurological disease or convulsions of unknown origin in early infancy who are born to mothers who have had midtrimester amniocentesis should have a CT scan as part of the investigations to exclude this rare but nevertheless important complication.     

水土化学体系中钙镁对土体结构强度贡献的试验研究

城市区域的土体环境一般是处在常态即常温、常压、缓变异的水化学环境中,在这种环境中,影响土体稳定的要素-土体中的化学组份扮演着重要的角色,而其对诸如地面沉降、土洞的产生都有重要影响。土体稳定受其结构强度控制,钙镁是土体结构构成中重要组成部分,理论与实践分析表明,在常态水环境下,其对结构往往起着控制作用,在常态水环境中,土结构的破裂面并不是通过颗粒本身,而是通过颗粒、颗粒集合体与集合体之间粒间连结。设计的常态水环境下的化学组份变异与CO2分压增高水环境下的室内模拟试验,揭示了化学组份钙镁对土体结构的贡献与对宏观强度的作用。     

土地利用改造规划的多因子空间分析

以福清市土地利用分布为例 ,在完成土地利用状况和土地适宜性参评因子空间数据库基础上 ,集成土地适宜性综合指数模型和地块紧凑度模型 ,开发了基于地理信息系统的土地适宜性评价和土地利用控制决策支持系统。通过土地适宜性多因子空间分析 ,模拟大农业 (耕地、林地、园地 )各目标用地条件下各地块土地使用适宜度 ,并结合土地利用现状 ,得到单目标土地改造方案 ;再经模型优化和综合比较得出多目标土地利用改造规划可选方案。计算结果表明 ,福清市土地资源中开发改造为新耕地的潜力极有限 ,而用于开发改造新林地和园地的土地尚有226 80km₂ 和36 34km₂ ,为福清市土地利用改造规划和总体规划的制定和调整提供了定量依据。     

Lead contamination in tea garden soils and factors affecting its bioavailability

The consumption of heavy metals is detrimental to human health and most countries restrict the concentration of metals such as lead (Pb) in food and beverages. Recent tests have detected high Pb concentrations in certain commercial brands of tea leaves and this finding has raised concerns for both producers and consumers. To investigate what factors may be contributing to the increase in Pb accumulation in the tea leaves we collected tea leaves and soils from tea producing areas and analyzed them for Pb concentration, pH and organic matter content. The result showed the Pb concentration of 47% investigated tea leaves samples was beyond 2 mg kg(-1), the permissible levels given by China. The total Pb concentration in the surface and subsurface soil layers averaged 36.4 and 32.2 mg kg(-1), respectively which fall below of the 60 mg kg(-1) limit provided for organic tea gardens in China. The pH of the tea garden soils was severely acidic with the lowest pH of 3.37. Soils under older tea gardens tended to have a lower pH and a higher Pb bioavailability which was defined as the amount of lead extracted by CaCl2 solution than those under younger tea gardens. We found that the concentration of bioavailable Pb and the percentage of bioavailable Pb (bioavailable Pb relative to total Pb concentration) were positively correlated with soil H+ activity and soil organic matter content, and the organic matter accumulation contribute more effects on Pb bioavailability in these two factors. We conclude that soil acidification and organic matter accumulation could contribute to increasing Pb bioavailability in soil and that these could increase Pb uptake and accumulation in the tea leaves.     

An unconventional approach to studying the reaction kinetics of the Fenton's oxidation of 2,4-dichlorophenoxyacetic acid

The Fenton's oxidation kinetics of herbicide 2,4-D at various [Fe(II)] and [H(2)O(2)] combinations was investigated and modelled through an unconventional approach. The reaction kinetics of 2,4-D degradation demonstrated a two-stage pattern of decay, where a very fast reactive stage was followed by a retardation stage due to the depletion of oxidants and to the competitive side-reactions of the intermediates (including 2,4-dichlorophenol, chlorohydroquinone and 2,6-dichlororesorcinol). A model characterized by two newly established constants, the initial decay rate and the maximum oxidative capacity, was proposed and proven capable of describing the two-stage process, which cannot easily be described by conventional first- or second-order kinetics approaches.