Adaptational strategy of a tropical shrub Carissa Carandas L. to urban air pollution

This paper reports the adaptational response of a tropical shrub Carissa Carandas L. to urban air pollution stress in Varanasi, India. Saplings of C. carandas were grown at a density of one per pot and kept for two years at 25 selected sites in the urban environment. Different sites received different levels of air pollution input. Changes in vegetative growth pattern (leafing and branching), in morphological features and in the distribution of biomass to above and below ground structures were considered in relation to the ambient air quality.Different levels of air pollution input produced different sets of harmful effects. Although the air pollution level at Varanasi reduced the plant height, basal diameter, canopy area, leaf area and total plant biomass of C. carandas, this species retained a major fraction of its photosynthate to above-ground plant parts where foliage assumes predominance. Since carbon gain is dependent not only on the rate of carbon acquisition per unit leaf tissue but also on the amount of photosynthetic tissue present, a shift in relative contribution of photosynthate to leaf production and shoot growth appears to be a pollution-induced adaptive response in C. carandas.     

Conservation practices in U.S. agriculture and their impact on carbon sequestration

Increase in the use of conservation practices byagriculture in the United States will enhance soilorganic carbon and potentially increase carbonsequestration. This, in turn, will decrease the netemission of carbon dioxide. A number of studies existthat calibrate the contribution of various individual,site-specific conservation practices on changes insoil organic carbon. There is a general absence,however, of a comprehensive effort to measureobjectively the contribution of these practicesincluding conservation tillage, the ConservationReserve Program, and conservation buffer strips to anchange in soil organic carbon. This paper fills thatvoid. After recounting the evolution of the use ofthe various conservation practices, it is estimatedthat organic carbon in the soil in 1998 in the UnitedStates attributable to these practices was about 12.2million metric tons. By 2008, there will be anincrease of about 25%. Given that there is asignificant potential for conservation practices tolead to an increase in carbon sequestration, there area number of policy options that can be pursued.     

Phthalate levels in Norwegian indoor air related to particle size fraction

Phthalates are found in numerous consumer products, including interior materials like polyvinyl chloride (PVC). Several studies have identified phthalates in indoor air. A recent case-control study demonstrated associations between allergic symptoms in children and the concentration of phthalates in dust collected from their homes. Here we have analyzed the content of selected phthalates in particulate matter (PM): PM(10) and PM(2.5) filter samples collected in 14 different indoor environments. The results showed the presence of the phthalates di-n-butyl phthalate (DBP), butyl benzyl phthalate (BBP), dicyclohexyl phthalate (DCHP) and diethyl hexyl phthalate (DEHP) in the samples. The dominating phthalate in both PM(10) and PM(2.5) samples from all locations was DBP. More than a 10-fold variation in the mean concentration of total phthalates between sampling sites was observed. The highest levels of total phthalates were detected in one children's room, one kindergarten, in two primary schools, and in a computer room. The relative contribution of total phthalates in PM(10) and PM(2.5) was 1.1 +/- 0.3% for both size fractions. The contribution of total phthalates in PM(2.5) to total phthalates in PM(10) ranged from 23-81%, suggesting different sources. Of the phthalates that were analyzed in the PM material, DBP was found to be the major phthalate in rubber from car tyres. However, our analyses indicate that tyre wear was of minor importance for indoor levels of both DBP as well as total phthalates. Overall, these results support the notion that inhalation of indoor PM contributes to the total phthalate exposure.     

焦化废水对蚕豆毒性的研究

以COD作为主要参照指标,研究了焦化废水在符合《钢铁工业水污染物排放标准》（GB13456-92）焦化一级、二级排放标准限值要求时,对蚕豆幼芽、幼根生长和根尖细胞遗传损伤的影响。结果表明,经处理达标后的焦化废水长时间作用于蚕豆时,蚕豆幼芽和幼根质量会受到影响,焦化废水会引起蚕豆细胞的遗传损伤。该废水诱导蚕豆根尖细胞微核率增加,出现核固缩,诱导蚕豆细胞根尖染色体断裂、粘连和染色体桥数量增加,破坏染色体的结构和遗传稳定性。     

Aluminium in UK rivers: a need for integrated research related to kinetic factors, colloidal transport, carbon and habitat

Dissolved aluminium concentrations ([Al]) in the <0.45 μm filtered fraction are described for 54 UK river sites covering rural, acidic/acid sensitive, agricultural and urban typologies, and wide pH range (4 to 11). High [Al] occurred under acidic conditions and for acid runoff neutralised by bicarbonate rich groundwater. Thermodynamic analysis indicates Al hydroxide/hydroxy-silicate oversaturation at circumneutral pH across the rivers, but undersaturation at lower/higher pH. The oversaturation reflects in part the presence of Al bearing colloids as indicated by (1) [Al] being correlated with components associated with both lithogenic (Fe, Ti and lanthanides) colloids and organic carbon, (2) baseflow studies using cross-flow ultrafiltration and (3) comparison of our data with Acid Waters Monitoring Network (AWMN) information on labile and non-labile Al. Tree harvesting and emission reductions of SO(x) in acidic and acid sensitive catchments in mid-Wales led to acidification reversal, lower [Al] and changing [H(+)] - [Al] relationships. The [Al] decline was confined to acidic conditions while [Al] increased during the later part of the monitoring period with a peak around 2002 for moorland and forested systems. Colloidal production across the flow range was indicated late in the record by comparison of our data with information collected by the AWMN for a site in mid-Wales. This production seems interlinked with organic carbon and with dissolved CO(2) changes. In order for further understanding of Al hydrogeochemistry in river systems there is a need to integrate research that moves from equilibrium to kinetic and colloidal consideration including the critical issues of organic and inorganic controls within the context of bioavailability and aquatic stress. The colloidal Al may well be of low environmental concern to fish and other factors such as habitat may well be critical.     

Mercury accumulation in selected tissues of shrimp Penaeus merguiensis from Musa estuary,Persian Gulf: variations related to sex,size, and season

The levels of mercury in tissues of Penaeus merguiensis from Musa estuary, northwest of the Persian Gulf, were investigated. This study assessed the relationship between mercury levels in hepatopancrea, gill, and muscle with sex, size, and season. The order of mercury concentrations in tissues of the shrimp P. merguiensis was as follows: hepatopancreas > gill > muscle. There was a positive correlation between mercury concentrations in shrimp species with sex and size of its food items. We expected to see higher mercury levels in tissues of female species because they are larger and can eat larger food items. Also, there was a positive correlation between mercury concentrations in shrimp species with its food source. Therefore, female species feed more on shrimp and plant and are contaminated with high levels of mercury. There was significant difference (p?<?0.05) in mercury levels between different seasons; higher mercury levels were found in July (summer season).     

Monitoring E. coli and total coliforms in natural spring water as related to recreational mountain areas

Natural spring water has unique properties, as it is rich in minerals that are considered to be beneficial to human health. A survey of the microbiological quality of natural spring water was conducted to assess possible risks from the consumption of the water by visitors in recreational mountain areas located in Seoul, South Korea. The densities of total coliforms and Escherichia coli were measured during the spring and the summer of 2002 to investigate the presence of coliform bacteria in the drinking spring waters. Total coliforms were detected in all samples and the mean density of total coliforms was up to a maximum of 228 CFU/mL. Detectable E. coli was found in 78% of all samples and the mean densities of E. coli varied from a minimum of 0 CFU/mL to a maximum of 15 CFU/mL in all samples. Malfunctioning septic systems and wildlife population appear to be the main source of E. coli contamination. Presence of E. coli in natural spring water indicates potential adverse health effects for individuals or populations exposed to this water. The fecal contaminated spring water may present an unacceptable risk to humans if it is used as raw drinking water.     

Spatial pattern and heterogeneity of soil organic carbon and nitrogen in sand dunes related to vegetation change and geomorphic position in Horqin Sandy Land, Northern China

To assesses the effect of geomorphology, topography, and vegetation changes on spatial pattern of soil organic carbon (C) and total nitrogen (N) in sand dunes, we used the quantitative methods to examine the spatial heterogeneity of vegetation cover, soil organic C, and total N in an 11-year naturally restored mobile dune (RMD11) and a 20-year naturally restored mobile dune (RMD20) that had been fenced to exclude grazing in Horqin Sandy Land, northern China. Our results showed that the vegetation cover, plant density, species number and diversity, soil organic C, and total N increased from RMD11 to RMD20 and increased from the 50 × 50-m plot (crest) to the 100 × 100-m plot (slope) in each dune. Geostatistical analysis showed that the spatial structural variance accounted for the largest proportion of the total sample variance in vegetation cover, soil organic C, and total N in each dune plot. Calculated spatial autocorrelation ranges of vegetation cover, soil organic C, and total N increased from RMD11 to RMD20, indicating that longer time since vegetation restoration results in a more homogeneous distribution of vegetation cover, soil organic C, and total N in sand dunes. In addition, the spatial continuity of vegetation cover, soil organic C, and total N decreased from the 50 × 50-m plot (crest) to the 100 × 100-m plot (slope) in each dune. These results suggest that the spatial distribution of soil organic C and total N in sand dunes is associated closely with geomorphic position related to the dune crest and slope, relative elevation of sampling site, and vegetation cover. Understanding the principles of this relationship between them may guide strategies for the conservation and management of semiarid dune ecosystems.     

Irrigational impact of distillery effluent on Abelmoschus esculentus L. Okra with special reference to heavy metals

The present study was performed under natural environment to assess levels of different heavy metals in soil and Abelmoschus esculentus plants along with soil microbial population irrigated with five rates of distillery effluent (DE) viz. 10, 25, 50, 75 and 100 % concentration in comparison with control (Bore well water). Results revealed that among various concentrations of DE, irrigation with 100 % DE significantly (P < 0.001) increased Zn (+63.46 %), Cu (+292.37 %), Zn (+3763.63 %), Cd (+264.29 %), Ni (+48.39 %) and Cr (+815.74 %), while decreased total bacteria (?45.23 %), fungi (?17.77 %) and actinomycetes (?42.57 %) in the soil. Enrichment factor of various heavy metals for soil was in the order Ni > Cr > Cd > Zn > Cu, and for A. esculentus plants, it was in the order Ni > Cr > Cu > Cd > Zn after irrigation with distillery effluent. The enrichment factor value was found maximum for Ni in comparison to other metals at 100 % DE concentration as compared with BWW. However, the values of these metals were below the recommended permissible limit.     

Methodology for designing air quality monitoring networks: II. Application to Las Vegas,Nevada, for carbon monoxide

An objective methodology presented in a companion paper (Liu et al., 1986) for determining the optimum number and disposition of ambient air quality stations in a monitoring network for carbon monoxide is applied to the Las Vegas, Nevada, area. The methodology utilizes an air quality simulation model to produce temporally-varying air quality patterns for each of a limited number of meteorological scenarios representative of the region of interest. These air quality patterns in turn serve as the data base in a two-step procedure for the identification and ranking of the most desirable monitoring locations (step 1) and the removal of redundancies in spatial coverage among the desired locations (step 2.)The performance of the air quality simulation model, a key element in the design methodology, was evaluated in the Las Vegas area in a special field measurement program. In the Las Vegas demonstration for carbon monoxide, 19 stations covering concentration maxima and 3 stations covering background concentrations in rural areas were identified and ranked. A 10-station network, for example, consisting of 7 stations for peak average concentrations and 3 stations for background concentrations, was selected for a desired minimum detection capability of 50% of concentration variations. Networks with fewer stations would be selected if smaller minimum detection capabilities of concentration variations are acceptable, and vice versa. Background stations could, of course, be deleted for networks with the sole purpose of discerning peak concentrations.Although the research described in this article has been funded wholly or in part by the United States Environmental Protection Agency through Contract No. 68-03-2446 to Systems Application, Inc., it has not been subjected to Agency review and therefore does not necessarily reflect the views of the Agency and no official endorsement should be inferred.     

Nucella lapillus L. imposex levels after legislation prohibiting TBT antifoulants: temporal trends from 2003 to 2008 along the Portuguese coast

Nucella lapillus (dog whelk) imposex levels were assessed along the mainland Portuguese coast in 2006 and 2008 and were compared with available data from 2003 for the same area. Given that specimen size has been described as a factor inducing variation in some of the imposex assessment indices, and thus resulting in less reliable results, new monitoring and data analysis procedures are described and applied to study change of imposex levels from 2003 to 2008. A significant decline in imposex intensity was observed in the study area during the study period, and the Portuguese coast ecological status (under the terms defined by the OSPAR Commission) notably improved after 2003, confirming the effectiveness of the Regulation (EC) No. 782/2003 in reducing TBT pollution. Nevertheless, N. lapillus populations are still extensively affected by imposex, and fresh TBT inputs were detected in seawater throughout the coast in 2006. These recent inputs are attributed to vessels still carrying TBT antifoulants applied before 2003, as their presence in vessels was only forbidden in 2008. Considering that Regulation (EC) No. 782/2003 is an anticipation of the IMO global ban entered into force in September 2008, a worldwide-scale decrease in TBT pollution can be expected in the near future.