恩施地区生态足迹和生态承载力评价

以恩施地区2010年统计数据为依据,对其2010年的生态足迹、生态承载力、生态盈余进行计算和分析,并将生态足迹、生态承载力、生态盈余和万元GDP生态足迹分别与恩施地区贫困村分布密度进行空间耦合。研究表明：（1）恩施地区人均生态盈余为0467 hm2,人均生态承载力为0947 1 hm2,人均生态足迹为048 hm2;（2）贫困村分布密度最高的来凤县、建始县人均生态盈余很少,而贫困村分布密度最低的利川市、咸丰县、宣恩县、鹤峰县,人均生态足迹最高和最低的县分别是咸丰县、宣恩县,鹤峰县的生态承载力最高,人均生态盈余最高的是宣恩县、鹤峰县,万元GDP生态足迹最高和最低的分别是利川市,巴东县;（3）通过生态足迹的研究,提出了恩施贫困地区需放大生态比较优势,〖JP2〗因地制宜,努力将生态盈余转化为直接的经济增长,使之能够有效的帮助贫困地区脱贫致富     

基于遥感反演长江中游地区悬浮泥沙研究

悬浮泥沙定量研究对于调查长江的水质、地貌、生态环境等起着至关重要的作用。以长江中游武汉地区2012~2013年14幅不同时相的Landsat ETM+遥感影像为主要数据源,结合野外采样悬浮泥沙浓度数据,分析了悬浮泥沙遥感定量反演方法,数据处理中针对ETM+SLC OFF影像缝隙问题,采用自适应局部回归匹配算法（ALR）进行影像自动恢复处理,在波段选择中对悬浮泥沙浓度和光谱反射率数据进行相关性分析,并运用传统关系建模方法和高斯模型方法对比,比较悬浮泥沙定量反演模型,利用实测验证数据对反演模型精度进行评估。研究结果表明：（1）ALR可以有效的获取悬浮泥沙敏感波段的遥感光谱反射率;（2）ETM+Band3悬浮泥沙浓度的高斯模型相关系数最高,通过对比得到模型反演的验证精度较高,研究证明遥感定量反演适合于长江流域武汉段泥沙含量大范围监测     

Enhanced nitrogen removal upon the addition of volatile fatty acids from activated sludge by combining calcium peroxide and low-thermal pretreatments

This study investigated a combined low-thermal and CaO₂ pretreatment to enhance the volatile fatty acid (VFA) production from waste activated sludge (WAS). The fermentative product was added to a sequencing batch reactor (SBR) as an external carbon source to enhance nitrogen removal. The results showed that the combined pretreatment improved WAS solubilization, releasing more biodegradable substrates, such as proteins and polysaccharides, from TB-EPS to LB-EPS and S-EPS. The maximum VFA production of 3529 ± 188 mg COD/L was obtained in the combined pretreatment (0.2 g CaO₂/g VS + 70 °C for 60 min), which was 2.1 and 1.4-fold of that obtained from the sole low-thermal pretreatment and the control test, respectively. Consequently, when the fermentative liquid was added as an external denitrification carbon source, the effluent total nitrogen decreased to Class A of the discharge standard for pollutants in rural wastewater treatment plants in most areas of China.     

Research on the evolution characteristics of future climate change in West Liao River Basin

Environmental Science and Pollution Research - In order to explore the characteristics of climate change in the future in the West Liao River Basin under the background of future climate change,...     

Short-term effects and economic burden assessment of ambient air pollution on hospitalizations for schizophrenia

Environmental Science and Pollution Research - The evidence on the health and economic impacts of air pollution with schizophrenia is scarce, especially in developing countries. In this...     

What are the disease burden and its sensitivity analysis of workers exposing to Staphylococcus aureus bioaerosol during warm and cold periods in a wastewater treatment plant?

Environmental Science and Pollution Research - Biological treatment in wastewater treatment plants releases high amounts of pathogenic bioaerosols. Quantitative microbial risk assessment is a...     

Comprehensive evaluation of land reclamation schemes in mining areas based on linguistic intuitionistic fuzzy group decision-making

Schemes to protect the geological environment and reclaim land are core requirements for an application for mining rights and complying with mining regulations. Mining enterprises must be supervised to ensure they fulfill their obligations. To guide oversight of such schemes and to provide references for their compilation and review, this study evaluates land reclamation schemes in mining areas using a multi-attribute group decision-making method. First, linguistic intuitionistic fuzzy numbers are used to describe the evaluation information. Considering the authority and preferences of experts, methods for determining expert weights in four cases are established. Max–min deviation then determines the attribute weights, and a method for linguistic intuitionistic fuzzy group decision-making is proposed. Finally, the practicability of this method is verified through a comparative analysis of land reclamation schemes for four mining areas in Sichuan Province, China. The results show the proposed method to give simple and effective evaluation, making it reasonably applicable to the compilation and review of land reclamation schemes.

     

Compression behaviors of mechanically biologically treated wastes of Tianziling landfill in Hangzhou,China

Environmental Science and Pollution Research - This study aimed to investigate the compression behaviors of mechanically biologically treated (MBT) wastes. For this purpose, the short-term...     

A novel sigma coordinate system to simulate abrupt changes of underwater terrain in a hydrodynamic model: application to Lake Mead,USA

The sigma (SIG) coordinate system in ocean circulation simulation models results inevitably in horizontal pressure gradient error. This problem also emerges in models of deep lakes or reservoirs with the same characteristics of underwater terrain mutation. SIG coordinates reflect vertical relative stratification but cannot be used to calculate horizontal pressure gradient force in places with drastic topographic changes; this results in vertical water temperature and circulation errors. In deep lakes or reservoirs, differences in water density caused by the temperature difference between upper and lower water bodies is the primary cause of thermal stratification phenomena. Lake Mead was used as a case study on steep topography based on Environmental Fluid Dynamics Code (EFDC) model in this study. SIG coordinates result in close agreement between the calibrated temperature time series at the top and middle water layers, but disparity in the bottom water layer. The error emerges in the horizontal pressure gradient error due to the SIG coordinate transformation. Neither increasing the vertical resolution nor adjusting the horizontal viscosity coefficient resolve this error. We test the sigma-zed (SGZ) coordinate which combines Z coordinate and SIG coordinate as a replacement for the SIG coordinate to find that they effectively reduce the model’s runtime and simulation efficiency. The vertical temperature distribution in SGZ coordinate mode is more accurate than the distribution in SIG coordinate mode. The Navier-Stokes horizontal gradient and advection diffusion equation results under SIG coordinates are very sensitive to the pressure gradient. The replacement also enhances resolution near the thermocline, facilitates reclosing of the water bottom and the equal sigma surface, lends significant advantages in terms of vertical temperature in the simulation for local deep water with steep terrain, and shortens runtime for 0.14 h. SGZ mixed coordinates are recommended in the simulation of deep lakes or reservoirs wherein the underwater topography is large (with abundant continuous deep trenches or reefs).

     

Indirect effect of nutrient accumulation intensified toxicity risk of metals in sediments from urban river network

The levels of metals in sediments of urban river ecosystems are crucial for aquatic environmental health and pollution assessment. Yet little is known about the interaction of nutrients with metals for environmental risks under contamination accumulation. Here, we combined hierarchical cluster, correlation, and principal component analysis with structural equation model (SEM) to investigate the pollution level, source, toxicity risk, and interaction associated with metals and nutrients in the sediments of a river network in a city area of East China. The results showed that the pollution associated with metals in sediments was rated as moderate degree of contamination load and medium-high toxicity risk in the middle and downstream of urban rivers based on contamination factor, pollution load index, and environmental toxicity quotient. The concentration of mercury (Hg) and zinc (Zn) showed a significant correlation with toxic risks, which had more contribution to toxicity than other metals in the study area. Organic nitrogen and organic pollution index showed heavily polluted sediments in south of the study area. Though correlation analysis indicated that nutrients and metals had different input zones from anthropogenic sources in the urban river network, SEM suggested that nutrient accumulation indirectly intensified toxicity risk of metals by 13.6% in sediments. Therefore, we suggested the combined consideration of metal toxicity risk with nutrient accumulation, which may provide a comprehensive understanding to identify sediment pollution.

Toxicity rate of metals in sediments from urban river network indirectly intensified by nutrients accumulation