基于模糊四元联系数的防洪工程体系安全综合评价模型

防洪工程体系是由随机、模糊、未确知等众多不确定性因子组成的复杂系统,它至今仍是洪水灾害管理的主体,对该体系综合安全进行定量评价可为洪水灾害管理提供重要依据.模糊四元联系数是集对分析中同异反联系数的推广,它可更深入地分析系统中的各种不确定性.利用模糊四元联系数建立了防洪工程体系安全综合评价模型,用联系度可描述评价对象与评价标准之间的关系,其结果简便直观,能清晰地反应评价对象和评价标准间的动态联系.用该模型综合评价了实际防洪工程体系的安全程度,其结果与物元分析等方法所得结果一致.     

三峡库区沙坝沟滑坡影响因素分析与稳定性评价

在不同工况下,通过采取不同的岩土体物理力学参数来计算沙坝沟滑坡的稳定系数并分析影响因素,得到影响该滑坡稳定性的主要因素为降雨、地下水作用及人类工程活动,在一定条件下可能成为滑坡失稳破坏的诱导因素。最后为滑坡防治提出一些建议,对滑坡的预测和防护提供依据。     

植物根瘤内痕量Frankia DNA的提取及鉴定

建立了一种简捷、快速植物根瘤内痕量Frankia DNA的提取方法,即采集自然态下根瘤,剥离瘤瓣,取瘤瓣尖经液氮研主民粉末,以20g/L CTAB（十六烷基三甲基溴化铵）消化胞壁,然后以d=5-10μm的石英粉吸附DNA,再以无菌去离子蒸馏水释放DNA,所获DNA产率及纯度较酚／氯仿法好。经对辽宁沙棘、色赤杨根瘤的瘤内痕量Frankia DNA及体外培养的9种Frankia菌株DNA分纯,并用于酶切及PCR,获满意结果。图3参12     

大气氟化物对橡胶树的伤害实验研究

通过熏气模拟试验研究氟化氢气体对橡胶盆栽幼苗的影响。结果表明 :熏气后 ,橡胶苗出现典型受害症状 ,熏气浓度越高 ,受害越严重 ,叶片氟的积累量也越高。幼叶总是先于老叶受害 ,老叶对于氟的累积量高于幼叶 ;随着熏气浓度升高 ,电导率明显增加 ;熏气后 ,气孔发生变形 ,而且熏气浓度越高 ,变形越厉害 ;随叶片受害程度加大 ,叶片失绿 ,叶绿素含量降低。     

Diversity of crude oil-degrading bacteria and alkane hydroxylase (<Emphasis Type="Italic">alkB</Emphasis>) genes from the Qinghai-Tibet Plateau

The aim of this study was to survey the response of the microbial community to crude oil and the diversity of alkane hydroxylase (alkB) genes in soil samples from the Qinghai-Tibet Plateau (QTP). The enrichment cultures and clone libraries were used. Finally, 53 isolates and 94 alkB sequences were obtained from 10 pristine soil samples after enrichment at 10 °C with crude oil as sole carbon source. The isolates fell into the phyla Proteobacteria, Actinobacteria, and Bacteroidetes, with the dominance of Pseudomonas and Acinetobacter. The composition of degraders was different from polar habitats where Acinetobacter sp. is not a predominant responder of alkane degradative microbial communities. Phylogenetic analysis showed that the alkB genes from isolates and enrichment communities formed eight clusters and mainly related with alkB genes of Pseudomonas, Rhodococcus, and Acinetobacter. The alkB gene diversity in the QTP was lower than marine environments and polar soil samples. In particular, a total of 10 isolates exhibiting vigorous growth with crude oil could detect no crude oil degradation-related gene sequences, such as alkB, P450, almA, ndoB, and xylE genes. The Shannon-Wiener index of the alkB clone libraries from the QTP ranged from 1.00 to 2.24 which is similar with polar pristine soil samples but lower than that of contaminated soils. These results indicated that the Pseudomonas, Acinetobacter, and Rhodococcus genera are the candidate for in situ bioremediation, and the environment of QTP may be still relatively uncontaminated by crude oil.     

Assessment of urban sustainability efficiency based on general data envelopment analysis: a case study of two cities in western and eastern China

Sustainable urban development focuses on enhancing urban well-being, while also balancing the demands of urban social and economic development, natural resource consumption, and environmental pollution. This work used general data envelopment analysis to assess the urban sustainability efficiency (USE) and sustainability potential (SP) in Lanzhou and Xiamen, two cities that are characteristic of urban areas in western and eastern China. The assessment indicator system included important natural and urban welfare factors as input and output indices, respectively. The results showed that overall urban sustainability efficiency increased in Lanzhou and Xiamen from 1985 to 2010, but that the sustainability of natural resources clearly decreased. The urban sustainability efficiency of Xiamen was higher than that of Lanzhou, and the sustainability potential of Xiamen was lower than that of Lanzhou; this indicates that Xiamen performed better in terms of urban sustainable development. The urban sustainability efficiency in Xiamen has increased with increasing urban population, and the rate and scale of economic development have been higher than in Lanzhou. The assessment and analysis performed in this study show that cities with different natural resources and development characteristics have different forms, patterns, and trajectories of sustainable development.     

Pollution characteristics and ecological risk assessment of heavy metals in three land-use types on the southern Loess Plateau,China

The accumulation of heavy metals in agricultural soils has been the subject of great concern because these metals have the potential to be transferred to soil solutions and subsequently accumulate in the food chain. To study the persistence of trace metals in crop and orchard soils, representative surface soil samples were collected from terrace farmland that had been cultivated for various numbers of years (3, 8, 12, 15, and >20 years), terrace orchard land that had been cultivated for various numbers of years (4, 7, 10, 12, 15, 18, 25, and >30 years), and slope farmland with various gradients (3°, 5°, 8°, 12°, 15°, and 25°) and analyzed for heavy metals (As, Cr, Cu, Hg, Ni, and Zn). These samples were collected from Nihegou catchment of Chunhua county in the southern Loess Plateau of China. The six heavy metals demonstrated different trends with time or gradient in the three land-use types. The Cu and Zn contents of the soil were higher than the referee background values of the loessal soil, and the contents of Cr and Ni, and especially those of As and Hg, were lower. Cu was the only heavy metal that just met the Grade III Environmental Quality Standard for Soils of China, while the others reached grade I. Cu and Hg were considered contaminant factors and Hg was a moderate potential ecological risk factor in the catchment. Of the sites investigated, 89.5% fell into the category with a low degree of contamination (C _d ) and rest were moderate, while all three land-use types had low potential ecological risk (RI). Changes of C _d and RI were consistent with the cultivated time in the terrace farmland and terrace orchard land. Values of RI increased while C _d decreased with the increasing of slope gradient in the slope farmland. Evaluating the ecological risk posed by heavy metals using more soil samples in a larger study area is necessary on the Loess Plateau of China.     

Understanding the Price Dynamics in the Jiangsu SO2 Emissions Trading Program in China: A Multiple Periods Analysis

Because emissions permits can be considered to be a pseudo-commodity, the permit price in the emissions trading markets has already attracted great interest from the economic literature. This research took the Jiangsu sulfur dioxide (SO₂) emissions trading program in China as a case study to examine the price dynamics over the next 10 years (2011–2020) based on Jiangsu’s new SO₂ emissions trading policy design. An adaptive agent-based simulation model was developed to estimate the price dynamics as well as the impact of energy price, policy design, and new environmental regulation on the permit price. The results showed that the equilibrium price of the Jiangsu SO₂ emissions trading market is approximately 4.20 CNY/kg, and the permit price will fluctuate around this price if the other conditions are not changed. If the coal price increases during 2011–2016, the permit price will decline to 2.79 CNY/kg by 2020 under China’s current coal–electricity price mechanism. In addition, the banking mechanism will smooth the price fluctuations and the average permit price will be generally higher when banking is not allowed. Finally, the stricter environmental regulation will reduce the market supply of permits and will raise the permit price. According to China’s potential new SO₂ discharge standard, the permit price will jump to 11 CNY/kg. The quantification of the permit price dynamics can help power plants to make decisions on emissions trading.