水污染事故中半挥发性有机物应急监测方法研究

建立了车载式气相色谱/质谱联用仪(GC/MS)结合固相微萃取(SPME)前处理技术测定水体中半挥发性有机物(SVOCs)的方法,优化了萃取头类型、萃取温度与萃取时间、离子强度、解吸温度与解吸时间、搅拌速度等影响萃取效率的因素,以及仪器分析条件.24种SVOCs、7种OPPs和17种OCPs在1.00 μg/L～40.0 μg/L范围内线性良好,检出限为0.11 μg/L～0.39 μg/L,空白加标水样平行测定的RSD≤14.3％,回收率为51.0％～98.5％.     

水产养殖规划环境影响评价关键指标的研究

建立水产养殖规划环境影响评价指标体系的实质就是建立其环境影响的具体评价内容.提出了水产养殖规划显著环境影响识别的必要性和方法,引入了关键控制点的概念和识别方法,提出了建立关键指标体系的方法.同时,根据水产养殖规划环境影响评价的要求,提出了规划层次的评价指标和水环境状态反应层次指标的两级指标结构层次.     

滇池福保湾沉积物-水界面微量重金属扩散通量估算

对滇池福保湾沉积物间隙水及近界面上覆水中溶解性重金属含量进行分析,并根据Fick定律计算出沉积物-水界面微量重金属扩散通量.结果表明,福保湾水体中重金属含量的平均值(以μg·1-1计)分别为:Fe 25.53,Cu 30.58,Zn 221.67,Ni 15.93,Co 1.91,Cd 1.12,Cr 19.26,Pb 31.08,As 9.41,符合国家Ⅱ类地表水质标准.沉积物-上覆水界面附近水体微量重金属浓度一般都明显高于孔隙水的相应浓度(As除外),根据Fick扩散定律计算出沉积物对上覆水中重金属的年吸附量(以kg计)分别为:Fe 3.48,Cu 8.70,Zn 70.66,Ni 4.52,Co 0.16,Cd 0.31,Cr 1.55,Pb 12.03,As 0.38.     

Sulfate-reducing bacterial community shifts in response to acid mine drainage in the sediment of the Hengshi watershed,South China

Environmental Science and Pollution Research - Sulfate-reducing bacteria (SRB) are an attractive option for treating acid mine drainage (AMD) and are considered to be of great significance in the...     

Linear Diamides Derivative-Nucleated Biodegradable Poly(ethylene succinate) Polyester: Crystallization Kinetics and Aggregated Structure Manipulated by Hydrogen Bond Interaction

Journal of Polymers and the Environment - A linear diamides derivative (TMC300) as a nucleating agent (NA) was incorporated into biodegradable poly(ethylene succinate) (PES) to investigate effect...     

Selenium protects against cadmium-induced kidney apoptosis in chickens by activating the PI3K/AKT/Bcl-2 signaling pathway

Cadmium (Cd) is a toxic heavy metal that can induce apoptosis. Selenium (Se) is a necessary trace element and can antagonize the toxicity of many heavy metals, including Cd. PI3K/AKT/Bcl-2 is a key survival signaling pathway that regulates cellular defense system against oxidative injury as well as cell proliferation, survival, and apoptosis. The antagonistic effects of Se on Cd-induced toxicity have been reported. However, little is known about the effect of Se on Cd-induced apoptosis in chicken kidneys via the PI3K/AKT/Bcl-2 signaling pathway. In the present study, we fed chickens with Se, Cd, or both Se and Cd supplements, and after 90 days of treatment, we detected the related index. The results showed that the activity of inducible nitric oxide synthase (iNOS) and concentration of nitric oxide (NO) were increased; activities of the mitochondrial respiratory chain complexes (complexes I, II, and V) and ATPases (the Na⁺-K⁺-ATPase, the Mg²⁺-ATPase, and the Ca²⁺-ATPase) were decreased; expression of PI3K, AKT, and Bcl-2 were decreased; and expression of Bax, Bak, P53, Caspase-3, Caspase-9, and cytochrome c (Cyt c) were increased. Additionally, the results of the TUNEL assay showed that the number of apoptotic cells was increased in the Cd group. By contrast, there was a significant improvement of the correlation indicators and occurrence of apoptosis in the Se + Cd group compared to the Cd group. In conclusion, our results confirmed that Se had a positive effect on ameliorating Cd-induced apoptosis in chicken kidney tissue by activating the PI3K/AKT/Bcl-2 signaling pathway.     

Multimethod,multistate Bayesian hierarchical modeling approach for use in regional monitoring of wolves

In many cases, the first step in large‐carnivore management is to obtain objective, reliable, and cost‐effective estimates of population parameters through procedures that are reproducible over time. However, monitoring predators over large areas is difficult, and the data have a high level of uncertainty. We devised a practical multimethod and multistate modeling approach based on Bayesian hierarchical‐site‐occupancy models that combined multiple survey methods to estimate different population states for use in monitoring large predators at a regional scale. We used wolves (Canis lupus) as our model species and generated reliable estimates of the number of sites with wolf reproduction (presence of pups). We used 2 wolf data sets from Spain (Western Galicia in 2013 and Asturias in 2004) to test the approach. Based on howling surveys, the naïve estimation (i.e., estimate based only on observations) of the number of sites with reproduction was 9 and 25 sites in Western Galicia and Asturias, respectively. Our model showed 33.4 (SD 9.6) and 34.4 (3.9) sites with wolf reproduction, respectively. The number of occupied sites with wolf reproduction was 0.67 (SD 0.19) and 0.76 (0.11), respectively. This approach can be used to design more cost‐effective monitoring programs (i.e., to define the sampling effort needed per site). Our approach should inspire well‐coordinated surveys across multiple administrative borders and populations and lead to improved decision making for management of large carnivores on a landscape level. The use of this Bayesian framework provides a simple way to visualize the degree of uncertainty around population‐parameter estimates and thus provides managers and stakeholders an intuitive approach to interpreting monitoring results. Our approach can be widely applied to large spatial scales in wildlife monitoring where detection probabilities differ between population states and where several methods are being used to estimate different population parameters.     

Environmental characteristics and land-use pattern changes of the Old Huanghe River delta,eastern China,in the sixteenth to twentieth centuries

The interaction between human and land in estuarine–coastal areas has become a focus of the global change research. Since the sixteenth century, the Old Huanghe River delta has experienced rapid accretion, the formation of rich ecological resources and diverse land use pattern changes; such information, in combination with a large number of historical documents, provides a unique research area for revealing the processes for ecosystem–human changes. We use historical documents and adopt multidisciplinary methods, to identify the relationship between ecosystem changes and human activities, on the basis of spatial and temporal analysis, for in the Old Huanghe River delta region. The results indicate that, in the sixteenth to nineteenth centuries, the long-term monopolistic development pattern under the government leadership, which occupied large quantities of ecological resources, controlled the coastal salt industry and marsh land exploitation. However, along with the delta ecosystem change and population growth, the development pattern became gradually unsustainable, i.e., the salt industry migrated toward the north, while the farming activities migrated toward the south with enhanced intensity of marsh reclamation. The government monopoly collapsed in the late nineteenth century, which enlarged the independent development space for the local residents, which, to a large extent, improved the land-use efficiency and reduced the population pressure.