Seagrass systems of the Western Pacific region are biodiverse habitats, providing vital services to ecosystems and humans over a vast geographic range. SeagrassNet is a worldwide monitoring program that collects data on seagrass habitats, including the ten locations across the Western Pacific reported here where change at various scales was rapidly detected. Three sites remote from human influence were stable. Seagrasses declined largely due to increased nutrient loading (4 sites) and increased sedimentation (3 sites), the two most common stressors of seagrass worldwide. Two sites experienced near-total loss from of excess sedimentation, followed by partial recovery once sedimentation was reduced. Species shifts were observed at every site with recovering sites colonized by pioneer species. Regulation of watersheds is essential if marine protected areas are to preserve seagrass meadows. Seagrasses in the Western Pacific experience stress due to human impacts despite the vastness of the ocean area and low development pressures.

This study assessed the level of contamination of the topsoil by Pb, Cu, Cr, Cd and Zn and the spatial distribution of these heavy metals around a cement factory. Thirty–eight composite soil samples were collected around the cement factory and subjected to nitric–perchloric acid digestion. Total metal contents of the soil were determined by flame atomic absorption spectrophotometry (FAAS) and the data generated were analyzed statistically. Spatial mapping of the distribution of heavy metals was done through the use of Inverse Distance Weighted technique (IDW) of ArcGIS 10. The results showed that the contamination domain of Cd was in the extreme domain while Pb and Cu levels in the soil were in the severe and moderate contamination domains. Zn and Cr posed no potential environmental hazard because of their low level in the soil. The spatial mapping of the heavy metals indicated Pb and Cu enrichment of the soil not only to come from cement production activities but also from vehicular activities while Cd enrichment of the soil was mainly from the cement production. Mapping of Zn and Cr distribution showed that their enrichments in the soil were from cement production activities. From these findings, it is highly recommended that environmental auditing of the cement production line be carried out to reduce the release of pollutants. It is also important that remediation activities be carried out on the soil to reduce the levels of Cd, Pb and Cu to avert potential ecological disasters.

Inverse modeling, coupled with comprehensive air quality models, is being increasingly used for improving spatially and temporally resolved emissions inventories. Of the techniques available to solve the corresponding inverse problem, regularization techniques can provide stable solutions. However, in many instances, it is not clear which regularization parameter selection method should be used in conjunction with a particular regularization technique to get the best results. In this work, three regularization techniques (Tikhonov regularization, truncated singular–value decomposition, and damped singular–value decomposition) and three regularization parameter selection methods (generalized cross validation, the L–curve method (LC), and normalized cumulative periodograms) were applied in conjunction with an air quality model with the aim of identifying the best combination of regularization technique and parameter selection method when using inverse modeling to identify possible flaws in an urban–scale emissions inventory. The bounded–variable least–squares method (BVLS), which is not usually considered a regularization method, was also investigated. The results indicate that the choice of the regularization parameter explains most of the differences between the regularization techniques used, with the LC method exhibiting the best performance for the application described here. The results also show that the BVLS scheme provides the best agreement between the observed and modeled concentrations among the mathematical techniques tested.

Continuous measurement of fine particulate black carbon (BC) was conducted at an urban site of Guangzhou in South China from December 2007 to December 2008. The daily average BC concentrations ranged from 0.6 to 20.5μg m−3, with an average value of 4.7μg m−3, which was substantially higher than those observed in the urban areas of other developed countries. Diurnal fluctuations of BC were marked with two peaks, one in the morning rush hour (08:00LT) and the other in the late evening hour (21:00–22:00LT), while the lowest BC concentrations were observed in the afternoon. Ambient BC concentrations displayed significant seasonal and diurnal variations with higher values in winter and spring, followed by lower concentrations during autumn and summer. Wind speed, wind direction and temperature were important meteorological factors that affected BC concentrations. A clearly negative correlation (r=−0.50, p<0.01) between BC concentrations and wind speed was found during the study period. A specific investigation was conducted to determine the relationship between optical BC and thermal–optical–reflectance elemental carbon (TOR EC) in distinct seasons. Although significant correlations between BC and EC were obtained (r>0.92, p<0.01), the regression slopes (ΔBC/ΔEC) slightly deviated from each other with values of 0.79, 1.18, and 0.81 in winter, spring and summer, respectively, possibly due to the distinct mixing states and source variations in different seasons. The calculated experimental attenuation coefficient showed a higher value (19.3m2g−1) in Guangzhou than the one recommended for typical Aethalometer measurements.

This is the first study to describe distribution and speciation of Hg in coastal sediments from the central east coast of India. The concentrations of Hg in the studied sediments were found to be much lower than the Hg concentration recommended in coastal sediments by the United State Environmental Protection Agency and the Canadian Council of Ministers of the Environment for the protection of aquatic life. This study suggests that the interactions between Hg and coastal sediments are influenced by particle size (sand, silt and clay) of the sediments and the total organic carbon (TOC) content in the sediments. It was found that the coastal sediments from the central east coast of India could act as a sink for Hg. The availability of strong uncomplexed-Hg binding sites in the coastal sediments was observed.

Atmospheric nucleation is now recognized to be an important source of ambient particles. In this study, ground–based measurements using a tower were used to observe new particle formation in the Morgan Monroe State Forest (MMSF) in Southwestern Indiana in May 2008. Nucleation was observed at MMSF on a number of days through examination of the particle size distributions. Most of these events were nucleation and growth events that are typical of regional nucleation phenomena. The particle size and sulfuric acid concentration data were used to investigate the mechanism for the observed nucleation events. Four of the ten observed nucleation events were clearly the result of activation of pre–existing clusters. The others seem likely to be the result of classical ternary nucleation.

Lactococcosis is prevalent on grey mullet (Mugil cephalus) in Hong Kong aquaculture resulting in serious economic loss. A compound formulation of Traditional Chinese Medicines (TCM) (modified Huanglian Jiedu decoction (HLJDD)) comprising Rhizoma coptidis, Radix scutellaria, Cortex phellodendri, Fructus gardeniae, Fructus forsythiae and Flos lonicerae japonicae (in a ratio of 3:2:2:3:3:5) were applied as feed supplements to deal with the disease. The Nitroblue tetrazolium activity in blood, bactericidal activity and total immunoglobulin in plasma were significantly enhanced after feeding 1% of this TCM for 28days. The disease resistances to Lactococcus garvieae in 1% and 2% TCM feeding groups were significantly enhanced. In the in vitro study, the modified HLJDD also activated the plasma bactericidal activities (p<0.01). Based on this study, 1% modified HLJDD feeding for 28days may be an optimal dose to prevent L. garvieae infection and could be used in aquaculture industries.

Susceptibility to pollution can be related to the flushing capacity of aquatic systems. Transport time scales constitute a useful tool for representing the water exchange and transport processes. A new transport time scale, recovery time, and a methodology to estimate it by means of numerical models is hereby developed. Recovery time, calculated in Gijon, Santander and Tarragona harbours, is significantly related to physical, chemical and biological water quality indicators. Susceptibility, assessed through recovery time values, provides spatial patterns of expected flushing capacity, being sensitive to physical and hydrodynamic characteristics. The developed method is appropriate to estimate recovery time and assess susceptibility against pollution in littoral waters having great potential to be applied to different disciplines. Recovery time could be used in littoral waters as a surrogate of water quality indicators, to establish efficient monitoring programs, to define and characterize modified water bodies or to improve the design of marine infrastructures.

The polycyclic aromatic hydrocarbons (PAHs) of 55 surface soil samples from the wetlands in the Liao River Delta, Northeast China were measured in order to apportion their sources. The total concentrations of 16 US EPA priority PAHs and alkyl-PAHs in this region ranged 106–3148ngg−1 (dry weight) (average: 550±565ngg−1) and 54–5564ngg−1 (average: 517±838ngg−1), respectively. Based on the positive matrix factorization analysis of alkylated and parent PAHs, six sources of PAHs were identified including petroleum (23%), biomass burning (23%), air–soil exchange (18%), coal combustion (17%), traffic emission (14%) and biogenic origin (6%). The positive correlation between low molecular weight (LMW) PAHs and TOC contents could demonstrate a potential positive influence of TOC on the accumulations of LMW PAHs in soils by the air–soil exchange. The petrogenic PAHs may pose a limited harmful effect on aquatic organisms although they were abundant in the area.