Some methodological and conceptual uncertainties in estimating the income component of the forest carbon cycle

Consideration is given to uncertainties related to methods for assessing the above and belowground phytomass and primary production of forest stands in test plots, as well as for extrapolating the results to forested areas.     

Soil-ecological conditions of the zone of salt waste dumping and plant adaptation to them

Technogenic surface formations near salt waste dumps are subject to salinization by sodium chloride. Synanthropic representatives of local flora that have adapted to salinization are characterized by increased concentrations of salinizing ions; redistribution of chlorides, with their predominant accumulation in above-ground organs; selective absorption with respect to sodium, chloride, and potassium ions; and decreased activity of hydrogen ions in cells.     

Determination of δ13C and δ15N and trophic fractionation in jellyfish: implications for food web ecology

Application of stable isotope analysis (SIA) in jellyfish allows definition of trophic patterns not detectable using gut content analysis alone, but analytical protocols require standardization to avoid bias in interpreting isotopic data. We determined δ¹³C and δ¹⁵N in Aurelia sp. from the northern Gulf of Mexico (30°00′N, 89°00′W–30°24′N, 88°00′W) to define differences in stable isotope composition between body parts and whole body, the effect of lipid extraction on δ¹³C in tissues, and fractionation values from medusa to prey. The isotopic composition of bell and whole Aurelia sp. was not different. The increase in δ¹³C values after lipid removal suggested a correction is needed. To aid future analyses, we derived a correction equation from empirical data for jellyfish samples. Laboratory feeding experiments indicated medusae increased +4 ‰ in δ¹³C and +0.1 ‰ in δ¹⁵N compared to their diet. These results suggest protocols commonly applied for other species may be inaccurate to define Aurelia sp. trophic ecology. Because Aurelia spp. are commonly found in marine ecosystems, accurately defining their trophic role by use of SIA has implications for understanding marine food webs worldwide.     

东平湖底泥重金属污染及其对摇蚊分布的影响

东平湖是南水北调东线的重要调蓄湖,其水环境状况对输水安全具有重要意义.为分析与评价东平湖底泥重金属污染状况及其与摇蚊分布关系,采集30个东平湖底泥样品,分别测试和鉴定其中的元素含量和摇蚊亚化石种属.运用地积累指数和生态危害指数法对东平湖底泥重金属污染进行分析评价,发现Cu、Pb、Zn、Ni是主要污染物,但污染程度相对较低,整体为轻度—中度污染水平,潜在生态危害性为轻微水平,且其污染及危害性均呈现出由湖区东南向西北逐渐降低的空间分布特征.其中,Cu污染最为严重,部分地区达到强污染水平.东平湖底泥共鉴定出41个摇蚊属种,主要优势种由Stempellinella-Zavrelia(30.88%)、Propsilocerus akamusi-type(26.79%)、Paratanytarsus(10.34%)、Cricotopus sylvestris-type(7.52%)和Hydrobaenus conformis-type(5.19%)组成.Stempellinella-Zavrelia和Propsilocerus akamusi-type是东平湖的绝对优势种,合占全湖的57.67%,且几乎呈全湖性分布.摇蚊RDA分析显示第一轴特征值为0.073,摇蚊种属与环境的相关关系达到了58.4%.RDA结果表明影响摇蚊组成分布的显著因子是Mn,并解释了7.3%的摇蚊变率.摇蚊属种Stempellinella-Zavrelia、Propsilocerus akamusi-type、Paratanytarsus、Hydrobaenus conformis-type等分布在Mn污染较小的区域.Pearson相关分析进一步表明东平湖底泥不同摇蚊种属对重金属Mn污染的响应存在显著差异.总体来看,底泥重金属对东平湖摇蚊组成和分布有显著影响,但不同金属对其影响存在差异.     

Benthic vegetation,chlorophyllα and physical-chemical variables in a protected zone of a Mediterranean coastal lagoon (Lesina,Italy)

Phytoplankton and benthic vegetation biomass undergoes spatial-temporal changes in relation to their life cycle, but also to meteorological conditions, physical-chemical variables, organic input and internal dynamism. The main aim of this work was to observe the effect of all environmental variables on the vegetative dynamic process in a protected zone of a Mediterranean costal lagoon (Lesina lagoon, SE Italy). Seven samplings were performed from 2010 to 2012 at 30 sites for nutrient and chlorophyll analyses, while TOC measurements and wet biomass evaluation were performed at 10 sites. Temperature, salinity and oxygen saturation were also measured by multiparametric probe and a visual census for vegetation was performed. Sites close to freshwater inflow were characterized by lower temperature and salinity, and high nitrate, with maxima of 191.05 μM in May 2010 and more than 250 μM in October 2010. Silicates drastically decreased from May 2010 (87.57 μM) to July 2010 (6.15 μM) and increased again in October (74.99 μM). Chl a concentrations were not on average higher than 6 mg m^?3, but peaks of 20 mg m^?3 were observed during May 2011 and May 2012. Benthic vegetation wet biomass collected in 2010 was approximately twice that collected in 2012, with a maximum of 27,554 g m^?2 and a dominance of macroalgae (70 % in May 2010 and 40 % in August 2010). During period 2010, a simultaneous and drastic decreasing of both mean values of wet biomass and chl a was observed from May to October 2010. During period 2012 a shift of vegetation biomass was shown from May (phytoplankton prevalence) to August 2012, with angiosperm prevalence (more than 30 %).     

Dynamic real-time risk analytics of uncontrollable states in complex internet of things systems: cyber risk at the edge

The Internet of Things (IoT) triggers new types of cyber risks. Therefore, the integration of new IoT devices and services requires a self-assessment of IoT cyber security posture. By security posture this article refers to the cybersecurity strength of an organisation to predict, prevent and respond to cyberthreats. At present, there is a gap in the state of the art, because there are no self-assessment methods for quantifying IoT cyber risk posture. To address this gap, an empirical analysis is performed of 12 cyber risk assessment approaches. The results and the main findings from the analysis is presented as the current and a target risk state for IoT systems, followed by conclusions and recommendations on a transformation roadmap, describing how IoT systems can achieve the target state with a new goal-oriented dependency model. By target state, we refer to the cyber security target that matches the generic security requirements of an organisation. The research paper studies and adapts four alternatives for IoT risk assessment and identifies the goal-oriented dependency modelling as a dominant approach among the risk assessment models studied. The new goal-oriented dependency model in this article enables the assessment of uncontrollable risk states in complex IoT systems and can be used for a quantitative self-assessment of IoT cyber risk posture.

     

Stakeholder perspectives on the value proposition of enterprise-level natural capital accounting for three primary industries

Environment Systems and Decisions - Globally we are experiencing a decline in aggregate natural capital. Many primary industries and enterprises are highly dependent on renewable and non-renewable...     

Effect of excess fluoride ingestion on human thyroid function in Gaya region,Bihar, India

Fluoride (F) is mainly ingested through drinking water and food. In addition to producing dental and skeletal fluorosis, excess fluoride may affect the functioning of many organs including the thyroid gland. The present study investigated the thyroid function of subjects with dental fluorosis from F-endemic areas of Gaya region, Bihar, India and compared it with control individuals from Bodh Gaya. The mean F concentration in groundwater of F-endemic area was 2.82 ± 0.18 mg/L (range 0.62–7.2 mg/L), while that of control area was 0.49 ± 0.04 mg/L (range 0.21–0.76 mg/L). Abnormal levels of T3, T4, and TSH were found in the study subjects from both control and F-endemic areas.     

Comparison of extraction methods for polycyclic aromatic hydrocarbon determination in sediments

Different sample preparation methods for the determination of polycyclic aromatic hydrocarbons (PAHs) in lake and river sediments were compared and evaluated. Freeze‐dried sediment materials were extracted using Soxhlet extraction, ultrasonic agitation and digestion with various solvents and solvent mixtures. Similarly, clean‐up methods using various types of sorbents for separation of PAHs tested.

The following method gives the best results for the determination of PAHs: freeze‐dried sediment samples were extracted using Soxhlet extractor with dichloromethane (6 hr, dark), extracts were cleanup using Silica gel and a mixture of n‐hexa‐ne‐dichloromethane was used for the elution of PAHs.

This method was used for the determination of 7 selected PAHs in sediment samples from Finnish lakes and Czech streams.     

Prostaglandin F2α facilitates female mating behavior based on male performance

Hormones play an important role in the regulation of reproductive behavior. Here, we examined the effects of the fatty acid derivative prostaglandin F2α (PGF2) on female sexual behavior as well as the interaction between PGF2-induced mating behavior with male courtship display in the lek-breeding African cichlid fish, Astatotilapia burtoni. In a two-way choice paradigm, we found that nonreproductive females preferred to associate with smaller, less aggressive males over larger, more aggressive males. However, PGF2-treated females dramatically reversed their preference to larger males. In a second experiment, PGF2 treatment dramatically increased sexual behavior in nonreproductive females as measured by time spent in the bower of the stimulus male, even when the female and the stimulus male were separated by a transparent divider. This effect was even more pronounced when the stimulus males were exposed to the putative female pheromone 17α,20β-progesterone (17α,20β-P). Under full-contact conditions, only PGF2-treated females visited a stimulus male’s bower, where they even displayed circling behavior usually only seen during spawning. Interestingly, male performance prior to PGF2 treatment predicted female sexual response. Our study demonstrates the importance of PGF2 in the control of female reproductive behavior in interaction with male performance.