围湖造田不同土地利用方式土壤有机碳和易氧化碳

围湖造田是我国20世纪50年代后期开始大量出现的与水争地的人类干扰活动。以太湖流域肖甸湖区为试验地,测定分析了该围湖造田区香樟（Cinnamomum camphora）林、水杉（Metasequoia glyptostroboides）林、毛竹（Phyllostachys heterocycla）林和农田4种不同典型土地利用方式35年后0～10 cm、10～20 cm、20～40 cm土壤有机碳和易氧化碳含量的差异,以及土壤易氧化碳的季节动态。结果表明：表层（0～10 cm）土壤有机碳含量林地显著高于农田,阔叶林高于针叶林。土壤易氧化碳含量随季节与土层深度的变化而变化,香樟林与毛竹林春夏季节大于冬季,水杉林与农田季节波动较平缓。4种土地利用方式下土壤有机碳和易氧化碳均随土层增加含量递减。与围湖地区内的溪流底泥相比,林地与农田表层土壤有机碳含量均有明显增加;与旱地发育的植被土壤相比,围湖后的土壤有机碳含量较低,易氧化碳含量较高,土壤有机碳稳定性较差。围湖造田作为人类对自然生态系统的一种干扰方式,显著改变了原有生态系统的碳循环特征,因此在研究全球碳循环中,围湖造田对生态系统碳循环的影响应该给予充分考虑。     

重金属Cd和Pb对土壤生物活性影响的初步研究

利用不同浓度的Ｃｄ、Ｐｂ溶液模拟污水农用，淋浇于蔬菜盆栽土壤上，研究其土壤生物活性的变化。结果显示，在试验所设置的浓度范围内．重金属Ｃｄ、Ｐｂ对土壤微生物三大菌和土壤酶中的蔗糖酶、脲酶等都有一定的抑制作用，三大菌对它们的敏感程度：Ｃｄ为细菌＞放线菌＞真菌，Ｐｂ为放线菌＞细菌＞真菌；而它们对土壤酶的抑制程度则都为蔗糖酶＞脲酶。研究还表明，土壤微生物总量的变化与重金属浓度有一定的相关性。     

基于PLS1的哈尔滨市PM2.5与空气污染物相关性分析

以往对PM2.5的研究多集中在气象因子或单一空气污染物对PM2.5质量浓度变化的影响,未考虑多种空气污染物对PM2.5质量浓度的协同作用。通过哈尔滨市环保局发布的2014年1月份（共31 d）市区内主要空气污染物SO2、NO2、PM10、CO、O3、PM2.5的质量浓度数据,运用相关性分析、PLS1和通径分析方法,研究哈尔滨市区内主要空气污染物对PM2.5质量浓度变化的直接影响、通过其他空气污染物的间接影响及污染物之间的协同作用。结果表明,SO2、NO2、PM10、CO 与 PM2.5质量浓度显著性相关,O3与 PM2.5质量浓度相关性不显著,SO2、NO2、PM10、CO 之间存在严重的复相关性。依据相关性分析结果,建立了SO2、NO2、PM10、CO对PM2.5质量浓度的PSL1模型,模型的拟合优度r2为0.852,模型拟合良好。对所建立的模型进行通径分析,结果显示,SO2、NO2、PM10、CO对PM2.5质量浓度变化的直接作用分别为0.005、-0.142、-0.140、1.191,CO对PM2.5质量浓度变化的直接影响作用最大。SO2、NO2、PM10通过CO对PM2.5质量浓度变化的间接作用分别为0.706、1.011、1.118均大于它们对PM2.5质量浓度变化的直接作用。SO2、NO2、PM10、CO对PM2.5质量浓度变化的总决定系数为85.9%。CO是主要空气污染物中影响PM2.5质量浓度变化的主要因素,降低冬季煤炭供暖期CO的排放量,有利于提高空气环境质量,降低对人体的健康危害。     

Dissipation and effect of chlorophenoxy herbicide on plant pigments and carbohydrates of sunflower (Helianthus annuus L.)

The dissipation pattern of the chlorophenoxy herbicides (2,4‐D and 2,4,5‐T) residues in sunflower plants (Helianthus annuus L.) has been studied along with its effect on the changes of plant pigments (chlorophyll‐a,b, total chlorophyll, carotene and anthocyanin), sugar and starch in different parts of the plant. The residues of 2,4‐D and 2,4,5‐T remained for larger period of time (10 days) at higher concentrations than the lower concentration. The concentrations of chlorophylls and carotene were found to be reduced with the application of both 2,4‐D and 2,4,5‐T. But the chlorophyll concentrations were slowly normalized accompanied with the reduction of the herbicide residues. For anthocyanin, there was no significant effect. In case of carbohydrate, the sugar concentration was found to be raised by all doses in leaf and stem. The change in starch content in different plant parts did not follow an uniform pattern at different doses of herbicides.     

Ontological changes in the crystallin composition of the eye lenses of the territorial damselfish Parma microlepis and their possible effects on trace-metal accumulation

The eye lenses of Parma microlepis from the rocky barrens of Sydney (New South Wales, Australia) were found to contain Ba, Hg, Rb, and Sr at concentrations above the quantitative detection limits of solution-based inductively-coupled plasma–mass spectrometry (ICP–MS). Lenses were separated into the hard central nucleus and the softer surrounding cortex. Nuclei contained lower (equal for Ba) concentrations of these metals. Biochemical analysis of the protein composition of these lenses revealed differences in the ratio of γ-crystallin to β-crystallin in the lens nucleus and cortex. These changes were shown to be attributable both to protein degradation and changes in protein synthesis as fish age. Such changes may lead to the loss of sequestered metals from older cell layers, or change the affinity of new layers for particular trace metals. Differential binding affinities of these crystallins may, therefore, partially account for trace-metal differences observed in the lens nucleus and cortex. Received: 13 November 1998 / Accepted: 23 April 1999     

Nitrogen critical loads for alpine vegetation and terrestrial ecosystem response: are we there yet?

Increases in the deposition of anthropogenic nitrogen (N) have been linked to several terrestrial ecological changes, including soil biogeochemistry, plant stress susceptibility, and community diversity. Recognizing the need to identify sensitive indicators of biotic response to N deposition, we empirically estimated the N critical load for changes in alpine plant community composition and compared this with the estimated critical load for soil indicators of ecological change. We also measured the degree to which alpine vegetation may serve as a sink for anthropogenic N and how much plant sequestration is related to changes in species composition. We addressed these research goals by adding 20, 40, or 60 kg N x ha(-1) x yr(-1), along with an ambient control (6 kg N x ha(-1) x yr(-1) total deposition), to a species-rich alpine dry meadow for an eight-year period. Change in plant species composition associated with the treatments occurred within three years of the initiation of the experiment and were significant at all levels of N addition. Using individual species abundance changes and ordination scores, we estimated the N critical loads (total deposition) for (1) change in individual species to be 4 kg N x ha(-1) yr(-1) and (2) for overall community change to be 10 kg N x ha(-1) x yr(-1). In contrast, increases in NO3- leaching, soil solution inorganic NO3-, and net N nitrification occurred at levels above 20 kg N x ha(-1) x yr(-1). Increases in total aboveground biomass were modest and transient, occurring in only one of the three years measured. Vegetative uptake of N increased significantly, primarily as a result of increasing tissue N concentrations and biomass increases in subdominant species. Aboveground vegetative uptake of N accounted for <40% of the N added. The results of this experiment indicate that changes in vegetation composition will precede detectable changes in more traditionally used soil indicators of ecosystem responses to N deposition and that changes in species composition are probably ongoing in alpine dry meadows of the Front Range of the Colorado Rocky Mountains. Feedbacks to soil N cycling associated with changes in litter quality and species composition may result in only short-term increases in vegetation N pools.     

长期定位施肥田土壤酶活性的动态变化特征

为探讨长期施肥条件下玉米生育期内土壤酶活性的动态变化及其与土壤肥力的关系,该文对北京褐潮土定位试验田第12年的土壤酶以及土壤养分因子进行了测定和分析.结果表明.土壤过氧化氢酶、磷酸酶在玉米拔节期出现活性高峰.土壤脲酶在玉米拔节期及成熟期出现两个活性高峰,土壤蔗糖酶在整个玉米生育期内活性变化幅度较小.长期施肥能明显提高土壤中蔗糖酶、脲酶、磷酸酶活性,其中有机肥与化肥配施对于增加土壤中蔗糖酶、脲酶、磷酸酶活性尤为显著.长期施肥降低土壤中过氧化氢酶活性.并且以NPK配施有机肥处理的土壤过氧化氢酶活性降低幅度最大.土壤酶之问及其与土壤养分因子之间具有明显相关性,其中蔗糖酶、脲酶及磷酸酶与土壤养分各因子均呈显著或极显著正相关,除碱解氮外,过氧化氢酶与其余各养分因子呈显著或极显著负相关.     

The energetic cost of protogynous versus protandrous sex change in the bi-directional sex-changing fish Gobiodon histrio

To investigate the relative cost of protogynous versus protandrous sex change we induced sex change in each direction in Gobiodon histrio (Gobiidae) and then compared growth, body condition and biochemical condition between sex-changed and non-sex-changed fish in treatment and control groups. Sex change in each direction was induced by establishing pairs of adult males and pairs of adult females on isolated coral colonies. Heterosexual pairs were used as controls. For both males and females, growth and body condition did not vary between fish that changed sex and those that did not. The relatively low cost of sex change, compared to the likely costs of searching for a mate of the correct sex, appears to explain the evolution of bi-directional sex change in coral-dwelling gobies. Lipid concentrations in the liver of males and females that changed sex were reduced by similar amounts (34% and 41%, respectively) compared to male and female controls that did not change sex. Therefore, changes in biochemical condition were approximately equal for fish that sex change in each direction and cannot explain the unequal frequency of sex change in each direction in natural populations of G. histrio.     

Changes in species composition of demersal fish fauna of Southeast Gulf of Carpentaria,Australia, after 20 years of fishing

The changes in a tropical demersal fish community in the southeast Gulf of Carpentaria, Australia, were examined by comparing the results of a survey undertaken in 1964 before the area was fished, with two surveys in 1985 and 1986 after 20 yr of commercial trawl fishing. The numerical abundance of 52 of the 82 fish taxa had not changed significantly, but that of 18 had decreased while 12 had increased. One taxon (Paramonacanthus spp.) had decreased by more than 500 times and another (Saurida micropectoralis) had increased substantially in abundance. The changes occurred throughout the area surveyed, but the largest changes were offshore. In the pre-trawling community most taxa were caught mainly during the night, while in the post-trawling community most were caught in the same numbers during day and night. In 10 of the 30 taxa that changed in abundance, changes were within a family and could not be explained. For the remaining 20, the changes could be related to their position in the water column: benthic taxa decreased and bentho-pelagic taxa increased. The changes were assessed in relation to fishing effort, and changes in the mud content of the substrate in the study area. Although the changes did not correlate with the fishing effort among three zones in the study area, it is suggested that fishing effort and discarding of the by-catch caused the change in 18 taxa. The magnitude of the decreases of some species might be related to changes in the sediment or possibly other long-term environmental change. There was also a change in the diel behaviour in the fish community that perhaps may be related to the effects of fishing on a tropical multispecies fish community.     

Estimating Effects of Tidal Power Projects and Climate Change on Threatened and Endangered Marine Species and Their Food Web

Marine hydrokinetic power projects will operate as marine environments change in response to increased atmospheric carbon dioxide concentrations. We considered how tidal power development and stressors resulting from climate change may affect Puget Sound species listed under the U.S. Endangered Species Act (ESA) and their food web. We used risk tables to assess the singular and combined effects of tidal power development and climate change. Tidal power development and climate change posed risks to ESA‐listed species, and risk increased with incorporation of the effects of these stressors on predators and prey of ESA‐listed species. In contrast, results of a model of strikes on ESA‐listed species from turbine blades suggested that few ESA‐listed species are likely to be killed by a commercial‐scale tidal turbine array. We applied scenarios to a food web model of Puget Sound to explore the effects of tidal power and climate change on ESA‐listed species using more quantitative analytical techniques. To simulate development of tidal power, we applied results of the blade strike model. To simulate environmental changes over the next 50 years, we applied scenarios of change in primary production, plankton community structure, dissolved oxygen, ocean acidification, and freshwater flooding events. No effects of tidal power development on ESA‐listed species were detected from the food web model output, but the effects of climate change on them and other members of the food web were large. Our analyses exemplify how natural resource managers might assess environmental effects of marine technologies in ways that explicitly incorporate climate change and consider multiple ESA‐listed species in the context of their ecological community. Estimación de los Efectos de Proyectos de Energía de las Mareas y el Cambio Climático sobre Especies Marinas Amenazadas y en Peligro y su Red Alimentaria     

Elemental composition of surface waters in the Antarctic Peninsula and interactions with the environment

The fast changes in chemical and biological properties of many coastal and inland waters in the last decades reflect the pressure of man on the environment. The surface waters of the Antarctic Peninsula, located far from industrial or populated areas, could eventually be used as background lines. Surface water samples were taken from five lagoons of King George Island, Antarctic Peninsula, and from the Kitiesh Lake. Sample pH and electrical conductivity were analysed in situ and in the laboratory, respectively. The dissolved fractions were analysed in 1997 and 1998. Total concentrations only for 1998 were determined in another fraction adjusted to pH 2. Aluminium, Ca, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Sr, Cd, Sn, Sb, Ba, Bi, and Pb were quantified in all samples by means of inductively coupled plasma-mass spectrometry (ICP-MS). Total and dissolved elemental concentrations were discussed considering the composition of particulate material suspended in the waters removed by streams or by water runoff, or from atmospheric aerosols. Concentrations of dissolved elements change from one lagoon to another. Total and dissolved elemental concentrations could be related to water movement by windstorms, to chemical mechanisms in water and/or to natural and anthropogenic atmospheric factors.     

Copper and zinc handling during the moult cycle of male and female shore crabs Carcinus maenas

Tissue concentrations and contents of copper and zinc were determined at 11 different stages of the moult cycle in male and female shore crabs Carcinus maenas. Metal concentrations in haemolymph, gills, midgut gland, muscle, and exoskeleton of males and haemolymph, gills, and midgut gland of females were determined, as were haemocyanin concentrations and haemolymph volumes (using ¹⁴C-inulin) in males. The changes in tissue Cu and Zn concentrations and contents that occur throughout the moult cycle can be attributed to muscle breakdown in late premoult, the period of starvation in late premoult and early postmoult, the resorption from and shedding of the old exoskeleton, and the dilution of the haemolymph caused by water uptake around the time of ecdysis. The present study demonstrates that whole-body Cu and Zn contents remain constant during a large part of the moult cycle of male and female C. maenas. This state of whole-body trace metal homeostasis is maintained in spite of major changes in tissue proportions and tissue Cu and Zn concentrations and contents. Previous studies have not carried out the necessary analysis to move from theoretical estimates to quantitative determination of the changes in tissue metal distribution associated with moulting in crustaceans; the data presented illustrate the necessity of measuring both tissue concentrations and contents of metals to avoid misinterpretation of either.     

Analysing the effects of soil properties changes associated with land use changes on the simulated water balance: A comparison of three hydrological catchment models for scenario analysis

This paper presents results of a model comparison study within the LUCHEM framework (‘assessing the impact of Land Use Change on Hydrology by Ensemble Modelling’) where the effects of land use change on catchment water balances were assessed with various hydrological catchment models. The motivation for this part of LUCHEM is that it is well known that land use changes may induce changes in soil chemical and soil physical properties (e.g. bulk density). Unfortunately the effects of land use change on soil hydraulic properties are seldom investigated directly, but some information on changes in bulk density is available. Changes in bulk density can be used as input for pedotransfer functions to derive changes in soil hydraulic model parameters. In this study, three different catchment models (SWAT, TOPLATS, WASIM) are compared with respect to their sensitivity to land use change with and without consideration of associated changes in soil parameterisation. The results reveal that different models show a different sensitivity to the change in soil parameterisation while the magnitude of absolute changes in simulated evapotranspiration and discharge is similar. SWAT calculates largest changes in the water balance in a German mesoscale catchment. TOPLATS also shows significant changes in the calculated catchment water balances as well as in the runoff generation while WASIM reacts least sensitive. While TOPLATS and WASIM show similar patterns with respect to changes in the water flows for all subcatchments and land use scenarios, SWAT results are similar for the different catchments, but show scenario specific patterns. In relation to the magnitude of the effects on simulated water flows induced by land use change, the significance of considering soil change effects depends on both, the scenario definition and on the model sensitivity to soil parameterisation. For two of the three land use scenarios representing an intensified land use, SWAT and TOPLATS simulate water balance changes in the same order of magnitude due to both, land use and soil property changes. Therefore, a consideration of changes in soil properties as part of land use change scenario analysis is recommended. Future field work needs to aim at the validation of the assumed dependency of soil hydrologic properties on land use change.     

Global Warming and the Species Richness of Bats in Texas

General circulation models provide predictions for global climate under scenarios of increased atmospheric CO₂. Climate change is expected to lead directly to changes in distributions of vegetation associations. Distribution of animals will also change to the extent that animals rely on vegetation for food or shelter. Bat species in Texas appear to be restricted, in part, by the availability of roosts. We used geographic information systems and the Holdridge vegetation-climate association scheme to model the effect of climate change on bat distributions and species richness in Texas. Habitat characteristics for each species were identified from the literature and included vegetation, topography, and availability of caves. We assumed caves and topography to be fixed relative to climate. Vegetation changes were predicted from the Holdridge vegetation-climate association scheme. The redistribution of bats following climate change was predicted based on the new locations of suitable habitat characteristics. Under conditions of global warming tropical forests were predicted to expand into Texas; tree-roosting bats were sensitive to this change in vegetation. Cavity-roosting bats were less affected by changes in vegetation, but, where response was predicted, ranges decline.     

微胶囊EDTA对2种土壤中铅释放的影响

选用不同铅污染程度及pH值的土壤,采用连续批浸提实验和土柱淋溶实验,比较研究微胶囊EDTA（Cap-EDTA）和未微胶囊化EDTA（Ncap-EDTA）对不同土壤溶液中pH值和铅离子浓度动态变化影响,以及土壤渗滤液中铅离子淋失特征。结果表明：施加2种不同形式的EDTA,可极显著地增加土壤溶液中铅离子浓度,Cap-EDTA能控制土壤溶液中铅浓度的突增幅度,且使土壤溶液中的铅持续保持在适度浓度的时间更长。同一种土壤不同处理间土壤pH值的变化趋势基本一致,无显著差异。施用2种不同形式EDTA可极显著地增加土壤渗滤液中铅离子含量,土壤铅累积淋失量呈对数曲线上升,但施用Cap-EDTA处理能显著降低土壤中铅的初始淋失量和淋失总量。在相同浓度及形式的EDTA下,高铅浓度和高pH值的土壤铅更易活化和淋失。因此,在进行污染土壤植物修复的EDTA调控时,采用微胶囊化EDTA,能降低其带来的污染地下水风险。     

Screening of thyroid gland histology in organohalogen-contaminated glaucous gulls (Larus hyperboreus) from the Norwegian Arctic

The associations between blood organohalogen contaminant (OHC) concentrations and thyroid gland histology were studied in 10 adult female glaucous gulls (Larus hyperboreus) from the Norwegian Arctic (Bjørnøya) during the incubation period. This histological investigation was undertaken as previous glaucous gull studies from the same area reported negative relationships between circulating OHC concentrations and thyroid hormone levels. Organohalogen concentrations have previously been associated with altered blood plasma thyroid hormone concentrations, as a result of parenchymal thyroid gland alterations and perturbation of the hypothalamic-pituitary-thyroid (HPT)-axis. In this study, PCB (range: 186–1027 ng g^?1ww), DDT (77–203 ng g^?1ww) and chlordane (18–65 ng g^?1ww) concentrations dominated the blood plasma OHC profile in incubating female glaucous gulls. High density of small follicles accompanied by follicular epithelial cell proliferations was seen in thyroid glands in seven of 10 gulls. Focal thyroiditis and nodular hyperplasia were found in two birds. No significant differences in plasma OHC concentrations were noted between gulls exhibiting high density of small follicles and cell proliferations and those birds not showing histological changes. Based on these findings, data suggest that the histological changes in thyroid glands of OHC-contaminated female glaucous gulls may be due to natural variance, although an OHC-induced thyroid stimulating hormone (TSH) perturbation resulting in epithelial cell hyperplasia and increased follicular density cannot be ruled out and remains to be verified. Hence, a large-scale histological study is required, in order to elaborate the potential linkage between changes in thyroid gland histology, OHC exposure and regulation of the HPT-axis in the Arctic-breeding glaucous gull.     

Paleoecology and the Coarse-Filter Approach to Maintaining Biological Diversity

Abstract: The difficulties of saving millions of species from extinction often cause conservationists to focus on a higher level of biological organization, the community. They do so for two reasons: (1) communities are considered important biological entities in their own right; and (2) conserving representative samples of communities is seen as an efficient way to maintain high levels of species diversity. This approach will work if the chosen communities contain almost all species. Because it potentially saves most but not all species, community conservation is a "coarse-filter" approach to the maintenance of biological diversity, and contrasts with the "fine-filter" approach of saving individual species. Paleoecological information on the distribution of plant taxa in North America, however, indicates that most modern plant communities are less than 8,000 years old and therefore are not highly organized units reflecting long-term co-evolution among species. Rather, they are only transitory assemblages or co-occurrences among plant taxa that have changed in abundance, distribution, and association in response to the large climate changes of the past 20,000 years. During periods when climate changes are large, communities are too ephemeral to be considered important biological entities in their own right. Large climatic changes are also likely to occur during the next century because of increased concentrations of CO₂, and we therefore propose that the coarse-filter approach to selecting nature reserves should be more strongly influenced by the distribution of physical environments than by the distribution of modern communities. Ideally, nature reserves should also encompass a broad enough range of environments to allow organisms to adjust their local distribution in response to long-term environmental change and should be connected by regional corridors that would allow species to change their geographic distributions.     

Gas–liquid chromatography for fenvalerate residue analysis: alterations in the ionic concentration and associated adinosine triphosphatases in fish,Cirrhinus mrigala (hamilton)

In the present study, an attempt has been made to quantify the fenvalerate accumulated in different tissues (gill, muscle and liver) and observe changes involved in the levels of sodium, potassium and calcium ions and Na⁺–K⁺, Mg²⁺ and Ca²⁺ adenosine triphosphatase (ATPase) activities in the freshwater fish, Cirrhinus mrigala on short-term and long-term exposure to the median lethal and sublethal concentration of fenvalerate. Residue analysis using gas–liquid chromatography (GLC) technique revealed that fenvalerate accumulated in highest quantity in gill followed by liver and muscle under median lethal concentration (6?µg?L^?1). Whereas in sublethal concentration (0.6?µg?L^?1), muscle accumulated highest quantity followed by gill and liver, which might be due to the fact that fenvalerate is highly lyphophilic. The ion concentration and ATPase activity were found effected in fish exposed to lethal and sublethal concentrations of fenvalerate. Concentration of Na⁺, K⁺ and Ca²⁺ ions decreased in gill, muscle and liver on being exposed to median lethal concentration to a significant level. Whereas the changes were not highly pronounced at sub lethal level indicating low concentration of fenvalerate and its non-toxic effect at chronic exposure. Na⁺–K⁺, Mg²⁺ and Ca²⁺ ATPases activity were also found decreased in correspondence to the ionic change under median lethal and sub lethal concentrations in target tissues. This might have lead to behavioural changes and create wide-spread disturbance in the normal physiology, ultimately causing the death of the fish. The results suggest that in biomonitoring programmes, ions and associated ATPases can be a good diagnostic tool for fenvalerate toxicity.     

双酚A对斑马鱼幼鱼神经递质和神经行为的影响

环境浓度水平下双酚A(BPA)暴露对生物体的毒性效应受到广泛关注。以早期发育阶段斑马鱼为模型,评价了环境浓度下BPA暴露对斑马鱼幼鱼运动行为的影响,并探讨了可能的作用机制。将斑马鱼胚胎暴露于不同浓度BPA(0、1、3、10和30"g·L-1)后,斑马鱼幼鱼的整体平均运动速率显著降低。低浓度组幼鱼在持续光照条件下的运动行为显著降低,同时5-羟色胺受体(htr1a)的转录水平增加十分显著,表明BPA可能通过5-羟色胺受体对斑马鱼的运动行为产生影响。而高浓度组幼鱼在第2个黑暗刺激周期的活动过度受到抑制,同时多巴胺受体(d1r)的转录水平显著降低,表明BPA可能通过多巴胺受体影响斑马鱼对外界刺激的响应。HPLC分析结果表明,5-羟色胺和多巴胺神经递质含量在所有浓度组均显著升高。进一步分析与早期神经发育(wnt1,shha)、单胺类递质神经元分化(lmx1a,nr4a2和syn2a)以及递质合成(tph1b,th)相关的基因和蛋白水平,发现神经递质含量的升高可能是由于BPA促进了斑马鱼胚胎早期神经发育和单胺类递质神经元的分化。综上,环境浓度下BPA暴露即可对斑马鱼的运行行为产生影响,提示BPA污染很可能对生态环境及人体健康产生潜在的危害。     

Corrosion rules for ordinary concrete exposed to sulfur dioxide-containing environments

Sulfur dioxide (SO₂) significantly influences the durability of concrete. Concrete corrosion in SO₂-containing environments is a serious concern. In this study, an accelerated test was devised to examine the change rules of concrete corrosion in SO₂-containing environments. Experiments were conducted to explore changes in mass, strength, and sulfatized depth with different water–cement ratios and a series of SO₂ concentrations. Data indicated that the water–cement ratio and SO₂ levels all impact the durability of concrete.