Distribution and partitioning of phosphorus in solid waste and sediments from drainage canals in the industrial belt of Delhi, India

Phosphorus is an essential and often limiting nutrient in both marine and freshwater ecosystems. However, its oversupply is of great concern in many environments due to its role in eutrophication. The concentration and distribution of sediment bound phosphorus species not only record its input into the environment, but also suggest their possible sources. It is recognized that the features of phosphorus behaviour have not been extensively studied in urban environments. In this study, phosphorus in solid waste and sediments from drainage canals within the industrial belt of Delhi were fractionated into five operationally defined forms, i.e., exchangeable or loosely sorbed phosphorus (Exch-P), Fe-bound phosphorus (Fe-P), authigenic apatite, CaCO3-bound phosphorus and biogenic apatite (Acet-P), detrital apatite (Det-P) and organic-bound phosphorus (Org-P), in order to assess the potential bioavailability status in these systems.     

Mechanisms of cross-shelf transport of crab megalopae inferred from a time series of daily abundance

From 20 July 1982 to 19 July 1984, crab megalopae were trapped daily from the Scripps Institution of Oceanography pier. Pachygrapsus crassipes, Portunus xantusii, Cancer spp., Hemigrapsus spp., and Majid crab megalopae dominated the catch. Yearly, seasonal, and daily variations in the magnitude of the catch were observed. Yearly and seasonal variations were probably due to a strong El Niño event that occurred during the study and to the timing of spawning and duration of the larval phase, respectively. Daily variation was correlated with oceanographic processes that can transport larvae to shore. Catch of some taxon during some seasons correlated with wind stress suggesting that transport was wind driven. The correlations were, however, weak and the sign of the correlation varied between years. The maximum daily tidal range was significantly correlated (cross-correlations and cross Fourier analysis) to both daily seawater temperature anomalies (surface and bottom) and daily catch of crab megalopae in all taxa enumerated. Significant correlations between tidal range and temperature anomalies suggest that temperature anomalies were primarily due to the shoreward transport of warm and cold water by the internal tides. The consistent and relatively strong relationship between tidal range and catch of megalopae (the cross-Fourier analysis suggests that from 20 to >90% of the variation in catch can be attributed to variation in the tidal range) suggest that much of the shoreward transport of megalopae was via the internal tides. Shoreward transport of larvae by internal tides may be due to internal cold bores or convergences over large tidally generated internal waves (solitons). Peak catches of megalopae, however, were often not associated with cold anomalies suggesting that transport was due to moving convergences over internal waves.     

First Jurassic Choristodera from Asia

Although choristoderes have a good Lower Cretaceous record in Asia, they have never previously been recorded from Jurassic deposits. Here we describe fragmentary vertebral material referable to Choristodera indet. from the Middle Jurassic Balabansai Svita of the Fergana Valley, Kyrgyzstan. This provides a significant range extension for the group in Asia and shows that choristoderes already had a Pan-Laurasian distribution in the Jurassic.     

Food remains in Confuciusornis sanctus suggest a fish diet

Despite hundreds of excellent fossils of Confuciusornis, the most abundant group of birds in the Early Cretaceous, ‘Jehol Biota’ in China, there is yet no indication of the food choice of these birds. Here, we describe fish remains preserved in the alimentary system of a specimen of Confuciusornis sanctus from the Jiufotang Formation. This find is about five million years younger than all previously published confuciusornithid birds from the Yixian Formation. Although it is unknown how common fish was in the diet of Confuciusornis, the find does not support previous hypotheses that it fed on plants or grain.     

Risk assessment for safety of soils and vegetables around a lead/zinc mine

Concentrations of heavy metals (Pb, Zn, Cd, Cu) were determined in soils and vegetables (chrysanthemum, spinach and four cultivars of Chinese cabbage from the area adjacent to a Pb/Zn mine in Shaoxing, Zhejiang province, China, and compared with the Chinese National Standards for Soil Environmental Quality. The accumulation of heavy metals in cabbage cv. Siyuegreen was investigated at different distances from the center of the mine. The vegetable plantation soils were polluted with Pb, Cd, Cu and Zn, especially by Pb and Cd. The levels of Pb and Cd were 20 and 30 times higher than the permitted standards, indicating that this Pb/Zn mining area is unsuitable for agricultural use. Chinese cabbage, chrysanthemum and spinach had different enrichment coefficients. The enrichment coefficient of Cd from soil to roots of chrysanthemum was >80% and from roots to leaves of cabbage cv. Shanghaigreen was >120%. These vegetables were polluted by heavy metals and could not be regarded as safe for human consumption. Environmental accumulation of heavy metals in the vegetable plantation soils was proportional to heavy metal accumulation in vegetables and both were inversely proportional to the distance from the lead/zinc mine.     

Ecotoxicological effect of grounded MV River Princess on the intertidal benthic organisms off Goa

The ecotoxicological effects of oil spill from the grounded vessel MV River Princess on the intertidal benthic organisms of Sinquerim-Candolim beach at Goa were investigated. An intertidal expanse of 1 km on either side of the grounded vessel was selected to evaluate the concentration of total petroleum hydrocarbon (TPH) in the sediment and its effects on the composition, abundance and diversity of micro-, meio- and macrobenthos. TPH in the intertidal sediment ranged from 7.8 to 89 microg g(-1) (mean 35.44+/-26.35 SD). Microbenthos comprised of microalgae, protozoans and juvenile forms of meiobenthos. Apart from juvenile nematodes, which were abundant, Coscinodiscus spp., Navicula spp., and Nitzschia spp. representing microalgae were also observed in microbenthic samples. Meiobenthos was represented by 13 taxa and their total density ranged between 92 and 1057 nos. 10 cm(-2). Maximum meiobenthic abundance of 1057 nos. 10 cm(-2) was observed at Sinquerim. Nematodes were the dominant meiobenthic taxa followed by turbellarians and harpacticoid copepods. The macrobenthos was numerically dominated by polychaetes, followed by crustaceans whereas bivalve molluscs were less represented. There was substantial increase in the petroleum concentration in the beach sediment compared to the previously reported values and highest TPH (89 microg g(-1) sediment) values were in the vicinity of the grounded vessel. The polychaete/amphipod ratio and cumulative and partial dominance abundance-biomass curves showed significant negative impact of TPH on macrofauna. The benthic community structure also showed measurable changes, as there was significant decrease (60%) in the number of species. Given that the microalgal counts were low in sediment, it is assumed that the intertidal meiofauna was possibly using oil-degrading bacteria as alternate food source. In conclusion, the results reported here suggest that the grounded ore carrier is not only detrimental to the beach community, that may take longer time for recovery, but also affects the beach morphology which may have long-term impact on local fishery.