Modeling of Cr contamination in the agricultural lands of three villages near the leather industry in Kasur,Pakistan, using statistical and GIS techniques

Kasur is one of the hubs of leather industry in the Punjab, Pakistan, where chrome tanning method of leather processing is extensively being used. Chromium (Cr) accumulation levels in the irrigation water, soil, and seasonal vegetables were studied in three villages located in the vicinity of wastewater treatment plant and solid waste dumping site operated by the Kasur Tanneries Waste Management Agency (KTWMA). The data was interpreted using analysis of variance (ANOVA), clustering analysis (CA), and principal component analysis (PCA). Interpolated surface maps for Cr were generated using the actual data obtained for the 30 sampling sites in each of the three villages for irrigation water, soil, and seasonal vegetables. The level of contamination in the three villages was directly proportional to their distance from KTWMA wastewater treatment plant and the direction of water runoff. The highest level of Cr contamination in soil (mg kg^?1) was observed at Faqeeria Wala (37.67), intermediate at Dollay Wala (30.33), and the least in Maan (25.16). A gradational variation in Cr accumulation was observed in the three villages from contaminated wastewater having the least contamination level (2.02–4.40 mg L^?1), to soil (25.16–37.67 mg kg^?1), and ultimately in the seasonal vegetable crops (156.67–248.33 mg kg^?1) cultivated in the region, having the highest level of Cr contamination above the permissible limit. The model used not only predicted the current situation of Cr contamination in the three villages but also indicated the trend of magnification of Cr contamination from irrigation water to soil and to the base of the food chain. Among the multiple causes of Cr contamination of vegetables, soil irrigation with contaminated groundwater was observed to be the dominant one.     

Limitations of recreational camera traps for wildlife management and conservation research: A practitioner’s perspective

The availability of affordable ‘recreational’ camera traps has dramatically increased over the last decade. We present survey results which show that many conservation practitioners use cheaper ‘recreational’ units for research rather than more expensive ‘professional’ equipment. We present our perspective of using two popular models of ‘recreational’ camera trap for ecological field-based studies. The models used (for >2 years) presented us with a range of practical problems at all stages of their use including deployment, operation, and data management, which collectively crippled data collection and limited opportunities for quantification of key issues arising. Our experiences demonstrate that prospective users need to have a sufficient understanding of the limitations camera trap technology poses, dimensions we communicate here. While the merits of different camera traps will be study specific, the performance of more expensive ‘professional’ models may prove more cost-effective in the long-term when using camera traps for research.     

Metal decontamination of tannery solid waste using <Emphasis Type="Italic">Tagetes patula</Emphasis> in association with saprobic and mycorrhizal fungi

A greenhouse trial was conducted to investigate the role of mycorrhizal and resistant fungi on heavy metal phytoextraction from different concentrations of tannery solid waste amended soil (10, 20, 50, and 100%) by Tagetes patula. The four treatments included were, the control (C) without any inoculum, mycorrhizal (M) inoculated with strongly mycorrhizal roots of Cynodon dactylon, fungal (F) inoculated with Trichoderma pseudokoningii and the combined inoculation with both mycorrhizal and fungal inocula (M + F). The dual inoculation increased plant biomass and phytoextraction ability of plant for metals like Cd, Cr, Cu, and Na. Plants given only fungus (F) and only mycorrhizal (M) treatment also showed significant growth rate as compared with control treatment. The statistical analysis of data indicated synergistic interaction between mycorrhizal and fungal inoculum promoting high biomass and enhanced metal phytoextraction. Thus using more than one group of rhizosphere fungi in association with a high biomass producing plant may be employed for rendering tannery solid waste free of metals.     

Biosorption potential and kinetic studies of vegetable waste mixture for the removal of Nickel(II)

Biosorption potential of new low cost biosorbent prepared from vegetable waste, composed of 1:1 mixture of potato and carrot peels for the removal of Ni(II) from aqueous solution was determined. The residual metallic ion concentrations were determined using an atomic absorption spectrophotometric technique (AAS). Batch experiments were conducted to optimize parameters such as initial pH, temperature, contact time, initial metal ion concentration and biosorbent dose and the results showed that maximum adsorption of Nickel (79.32 %) occurs when the contents were stirred for 75 min with 3.0 g of biosorbent at 35 °C and pH 4. Kinetic studies of the reaction revealed that it follows a pseudo-second order reaction. The experimental results were analyzed in terms of Langmuir and Freundlich isotherms. The Langmuir isotherm model fits well to data of Ni(II) biosorption by the prepared biomass as compared to the model of Freundlich. Both neat and Ni loaded biosorbent samples were analyzed by AAS using a dry ashing process in a furnace and also by use of a FT-IR spectrophotometer and an X-Ray florescence spectrometer in order to confirm the biosorption of Ni(II) and the results have revealed that a significant amount of Ni is present in the spent biosorbent.     

Bioavailable DDT residues in sediments: laboratory assessment of ageing effects using semi-permeable membrane devices

We describe the reduction in bioavailability of DDT in contaminated soil after it was incubated as sediment for 365 d. Bioavailability was assessed using semi-permeable membranes. Contaminated soils from three cattle dip sites, one spiked paired uncontaminated site, and one spiked OECD standard soil were studied. Sandy soil with residues of 1880 mg/kg summation operator DDT incurred since 1962, initially had 4.6% of summation operator DDT available, reducing to 0.6% following 365 d. Clay soil (1108 mg summation operator DDT/kg) had 4.1% initially available, reducing to 0.3% after 365 d. Freshly spiked soils had a greater amount of DDT initially available (10.9%), but this reduced to 1.5% by the end of the incubation. Of the DDT congeners, both o,p'-DDD and p,p'-DDD were most bioavailable in the soils, but also had the most significant decrease following incubation.     

The effects of self‐emotion,counterpart emotion,and counterpart behavior on negotiator behavior: a comparison of individual‐level and dyad‐level dynamics

This study expands the negotiation literature by examining how negotiator behavior is predicted by various emotions felt by the negotiators and their counterparts and by counterpart negotiation behavior. Using hierarchical linear modeling, we also compare individual‐ and dyad‐level processes that lead to negotiator behavior and outcomes. The results from a dyadic negotiation simulation showed that both the valence and agency of negotiator and counterpart emotions need to be considered to understand the roles of emotion in negotiator behavior. Negotiators tend to reciprocate counterparts' integrating, compromising, and dominating behaviors, but they also offer complementary (or matching) responses to the counterparts' dominating and yielding behaviors. Integrating behavior was more dependent on dyad‐level interpersonal dynamics than were the other behaviors. The comparison of negotiator‐level and dyad‐level results suggests that negotiation needs to be understood in the context of collective exchanges as well as individual‐level cognitive processes. Copyright © 2005 John Wiley & Sons, Ltd.     

Occupational health and safety issues in the informal economic segment of Pakistan: a survey of construction sites

This research covers the current status of occupational health and safety (OHS)-related practices in the informal construction segment of Pakistan. Data were collected, through interviews, from 316 construction sites employing 3577 workers. The results of the study reveal that both employers and workers lack knowledge of OHS laws/standards and no practices of this nature are enacted at these construction sites. Alarmingly, work-related accidents, whenever they happen, are not given due attention and there is no formal injury-report system. The informal construction industry employs a huge portion of the informal workforce, and lack of OHS happens at tremendous human cost. These research findings may thus play their role in strengthening the case for reforms in the sector. This study, if properly utilized, may also enable employers of the sector by increasing their knowledge about OHS practices and, as a result, trying to offer safer environments for their workers.     

Environment,mining and the Lesser Developed Countries

Mineral activities are a potential source of environmental damage, but the traditional role of minerals and metals in material well-being of man is too easily forgotten in the rigmarole of environmental protective response especially among the inhabitants of the Industrially Developed Nations (IDN). It is imperative that the needs and interests of both the mining industry and the environmentalists converge to a common point of understanding for the continued economic development of the world.People of the Lesser Developed Countries (LDC) on the other hand, are caught in a vicious struggle of basic existence and any talk of environmental damage/protection is, therefore, extraneous to their way of life. But the modern tools of progress so eagerly sought by the LDC for the development of their resources including minerals could destroy their environment, very likely beyond repair, if their public policy objectives do not include any timely preventive measures for the protection of their environment.