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141.
Currently, several state and federal agencies are proposing upper limits on soil test phosphorus (P), above which animal manures cannot be applied, based on the assumption that high P concentrations in runoff are due to high soil test P. Recent studies show that other factors are more indicative of P concentrations in runoff from areas where manure is being applied. The original P index was developed as an alternative P management tool incorporating factors affecting both the source and transport of P. The objective of this research was to evaluate the effects of multiple variables on P concentrations in runoff water and to construct a P source component of a P index for pastures that incorporates these effects. The evaluated variables were: (i) soil test P, (ii) soluble P in poultry litter, (iii) P in poultry diets, (iv) fertilizer type, and (v) poultry litter application rate. Field studies with simulated rainfall showed that P runoff was affected by the amount of soluble P applied in the fertilizer source. Before manure applications, soil test P was directly related to soluble P concentrations in runoff water. However, soil test P had little effect on P runoff after animal manure was applied. Unlike most other P indices, weighting factors of the P source components in the P index for pastures are based on results from runoff studies conducted under various management scenarios. As a result, weighting factors for the P source potential variables are well justified. A modification of the P index using scientific data should strengthen the ability of the P index concept to evaluate locations and management alternatives for P losses.  相似文献   
142.
Cheng SH  Chan KW  Chan PK  So CH  Lam PK  Wu RS 《Chemosphere》2004,55(10):1387-1394
The effect of cadmium on stage II naupliar larvae of barnacle (Balanus amphitrite Darwin) was investigated. Barnacle larvae were exposed to 0-15 microM CdCl(2) for 24 h. Apoptotic cells were stained by the terminal deoxyribonucleotidyl transferase mediated dUTP nick end labelling (TUNEL) method. Incidence of apoptosis, as measured by numbers of animals with ectopic pattern of apoptosis as well as numbers of apoptotic cells per animal, was assessed using confocal microscopy. An increase in incidence of apoptosis was observed in the experimental animals with an increase in cadmium concentration. Mortality increased, and motility decreased, when barnacle larvae were exposed to an increasing concentration of cadmium. The relationship between the occurrence of apoptosis and swimming behaviour was investigated in larvae exposed to 10 microM CdCl(2). Significant increases in apoptosis were detected in the non-motile and dead nauplii. This study suggested that whole-mount in situ TUNEL method may be used to study increased occurrence of apoptotic cells in crustacean larvae.  相似文献   
143.
立体式植物修复受重金属污染农田土壤的探讨   总被引:1,自引:0,他引:1  
农田土壤遭受重金属污染是江西省乐平市乐安河沿岸的重要环境问题。采用实验小区的方法,研究了乔、灌、草多层次植物对重金属污染地区土壤的修复作用。结果表明,利用木本植物和对重金属吸收较好的草本植物组成立体模式来净化污染面积较大的土壤,效果明显,简便易行,经济效益大,是治理重金属Cu、Cd复合污染的一条新途径。  相似文献   
144.
Eco-labelling is the practice of eco information provision that most directly addresses consumer behaviour. Nowadays, consumers are facing difficulties in perceiving and understanding existing eco labels. In previous work, we proposed the conceptual framework of eco information individualisation which tailors eco labels according to the specific needs of individual users using contextual technologies. This paper extends the conceptual framework by introducing a more structured way of considering the personal data and product data requirements, and reports the development of a design toolkit that aims to support designers in the designing of individualised eco information. A design workshop was carried out to introduce the concept to designers, and evaluate the usability and usefulness of the toolkit. Positive responses were received. The design outputs generated from the workshop were considered largely feasible and have the potential to be developed into digital prototypes. These indicate that it is possible for designers to learn to design eco information individualisation in a short time. This paper is a step towards a greater understanding of designing individualised eco information.  相似文献   
145.
Environmental Science and Pollution Research - This paper takes energy consumption PM2.5 emission as research object, and quantitatively analyzes the PM2.5 emission level in Hunan and Guangdong...  相似文献   
146.
崇明岛小白鹭鸟卵中有机磷阻燃剂污染特征   总被引:1,自引:0,他引:1  
鸟卵可用于环境质量的生物监测.从崇明岛东部若干林地采集小白鹭(Egretta garzetta)卵样品10个,用液相色谱-串联质谱联用仪(LC-MS/MS)测定了样品中10种常见有机磷阻燃剂(OPFRs)的含量,分析了其分布特征和来源.结果表明,除三辛基磷酸酯(TEHP)和三氯乙基磷酸酯(TCEP)外,其余8种OPFRs在小白鹭卵中均有检出,OPFRs的总含量为49.5~142.8 ng·g~(-1)(以湿重计,下同),均值为78.6 ng·g~(-1);其中,三丁基磷酸酯(TNBP)、三异丁基磷酸酯(TIBP)和三邻甲苯磷酸酯(TMPP)含量较为丰富,分别为(26.3±10.1)、(20.9±9.44)和(19.0±15.6) ng·g~(-1).不同鸟卵中OPFRs的赋存特征差异较大,主要受其环境含量水平、生物积累和放大能力及代谢能力的影响.崇明小白鹭卵样品中存在具有胚胎发育毒性的TMPP、三(1-氯-2-丙基)磷酸酯(TCIPP)、三丁氧基乙基磷酸酯(TBOEP)等,可能对其繁殖具有潜在影响,值得关注.  相似文献   
147.
Increased market internationalization with more and stricter environmental regulations in different countries has caused manufacturers to extend their environmental management practices to cover their supply chain partners. Thus, environmental supply chain management (ESCM) has become an important competitive and environmental strategy for manufacturers to pursue. China, as a global manufacturer, is also facing this balance of economic development with environmental protection. The literature remains unclear on whether internationalization is beneficial or costly when it comes to environmental management practices such as ESCM within China. Further insight into this issue will be useful for organizations in developing and emergent economies to more effectively prepare for internationalizing their operations and markets. Using internationalization drivers that propel the implementation of environmental management practices in the Chinese manufacturing industry, we applied cluster analysis to group a sample of 377 Chinese manufacturers surveyed in 2007 into three clusters: mature internationalization, emergent internationalization, and domestic-focused. Institutional theory within an internationalization context sets the theoretical foundation for evidence that the international environmentally oriented institutional drivers encountered are positively associated with the adoption of ESCM practices by Chinese manufacturers. We also find significant differences in the environmental, economic and operational performance outcomes across the three manufacturer clusters. We conclude that manufacturing organizations experiencing internationalization with a greater extent of adopting ESCM practices tend to perform better.  相似文献   
148.
Solid phase microextraction (SPME) coupled with gas chromatography was employed to estimate bioavailability of pyrene in soils with different properties of textures, organic matter contents (SOM) and aging periods. Experimental results indicated that biodegradation rates increased from 0.10 (sandy loam) to 0.15 (silty loam) microg g-1 hr1. By contrast, biodegradation rate decreased from 0.10(1.3% SOM) to 0.04 (7.6% SOM) microg g-1hr1. The amounts of pyrene biodegraded decreased 27% when SOM was modified from 1.3 to 7.6%, indicating that distributions of pyrene in soils at biodegradation end points were affected by the SOM. Sequestration as measured by sonication extraction had evidently occurred in aged soil samples. SPME measurements slightly overestimated the amount of pyrene degraded by indigenous and seeded microorganisms, in soils with the different properties (correlation coefficient, R2= 0.74). The present study demonstrates that the SPME method can not replace biodegradation tests commonly used for predicting bioremediation efficacy.  相似文献   
149.
150.
在实地调查和数量系统分析的基础上,论述了九岭幕阜山中国种子植物特有属的物各多样性,空间分布格局及其区系地理特征,探讨了本区与邻近地区中国种子植物特有属分布的联系及其重要地位,并对特有属的生物多样性保护提出了具体对策。  相似文献   
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