Organochlorine residual concentrations in cattle egret from the Punjab Province, Pakistan

In this study, residual concentration of organochlorine pesticides (OCPs) in the sediments, prey, and eggs of Bubulcus ibis were measured from three breeding heronries from the Punjab province of Pakistan. Pattern of contamination in eggs followed the order: DDTs > HCHs > heptachlor > aldrin. Overall, pesticide residual concentrations were greater in eggs of cattle egrets collected from heronry on the River Ravi. Among HCHs, ??-HCH was more prevalent in eggs, whereas DDTs followed the order: DDD > DDE > p,p ^??-DDT > o,p ^??-DDT. Eggshell thinning was detected which showed negative relationship with residual concentration of DDE. In prey samples, residual concentration of POPs followed the order: DDTs > HCHs > dicofol > heptachlor; however, contamination pattern in sediments followed a slightly different order: DDTs > heptachlor > dicofol > HCHs > dieldrin > aldrin. Concentration of ??-HCH was more prevalent in sediments and comparatively greater concentrations of POPs were measured in sediments collected from the River Ravi. Dicofol was found for the very first time in the biological samples from Pakistan, and its concentration was measured as relatively high in eggs from heronry from the River Chenab. Residual concentrations measured in eggs were below the levels that could affect egret populations. Biomagnification of the total OCPs through the food chain was evident in three breeding heronries. The concentration of DDE measured in eggs of the cattle egret suggests the need for monitoring this contaminant in other bird species at different trophic levels.     

Phytoremediation of cadmium-contaminated soil by Bidens pilosa L.: impact of pine needle biochar amendment

Environmental Science and Pollution Research - The objective of the present study was to evaluate the feasibility of pine needle biochar as a soil amendment to promote the growth of Bidens pilosa...     

Insights into conventional and recent technologies for arsenic bioremediation: A systematic review

Environmental Science and Pollution Research - Arsenic (As) bioremediation has been an economical and sustainable approach, being practiced widely under several As-contaminated environments....     

Plant growth regulators and EDTA improve phytoremediation potential and antioxidant response of Dysphania ambrosioides (L.) Mosyakin & Clemants in a Cd-spiked soil

Environmental Science and Pollution Research - Soil pollution due to potentially toxic elements is a worldwide challenge for health and food security. Chelate-assisted phytoextraction along with...     

Exploring natural colorant behavior of husk of durum (Triticum durum Desf.) and bread (Triticum aestivum L.) wheat species for sustainable cotton fabric dyeing

Environmental Science and Pollution Research - Revival of natural colorants in textile dyeing is one of the important strategies to reduce synthetic chemical-based environmental pollution. The...     

A heuristic approach to stochastic cutoff grade optimization for open pit mining complexes with multiple processing streams

Cutoff grade specifies the available supply of metallic ore from an open pit mine to the multiple processing streams of an open pit mining complex. An optimal cutoff grade strategy maximizes the net present value (NPV) of an open pit mining operation subject to the mining, processing, and marketing/refining capacity constraints. Even though, the quantities of material flowing from the mine to the market are influenced by the expected variation in the available metal content or inherent uncertainty in the supply of ore, the majority of cutoff grade optimization models not only disregard this aspect and may lead to unrealistic cash flows, but also they are limited in application to an open pit mining operation with single processing facility. The model proposed herein determines the optimal cutoff grade policy based on a stochastic framework that accounts for uncertainty in supply of ore to the multiple ore processing streams. An application on a large-scale open pit mining operation develops a unique cutoff grade policy along with a portfolio of mining, processing, and marketing/refining rates. Owing to the geological uncertainty, the approach addresses risk by showing a difference of 14% between the minimum and maximum production rates, cash flows and NPV.     

Gaining forests but losing ground: A GIS evaluation in a Himalayan watershed

GIS overlay techniques were used to provide a quantitative historic documentation of deforestation and land-use dynamics in the Middle Mountains of Nepal between 1947 and 1990. Deforestation was most critical in the 1960s, but active afforestation programs in the 1980s have reversed the process. In spite of these trends, the degradation problem is more complex. The GIS evaluation showed that 86% of the recently afforested land is now under pine plantations located primarily at lower elevations and moderately steep slopes. In contrast, rainfed agricultural expansion is most pronounced on acidic soils and steeper, upper elevation sites, suggesting marginalization of agriculture. Agricultural expansion coupled with major losses of grazing land to pine forests are the key processes pointing towards major animal feed deficits. An alternative animal feed source is suggested through GIS using a topographically based microclimatic classification to generate a tree-planting map where the optimum ecological conditions for selective native fodder tree species are identified.     

Greenbelt conservation as a component of ecosystem,ecological benefits and management services: evidence from Peshawar City,Pakistan

Environment, Development and Sustainability - Conservation of greenbelts is the most enduringly successful and popular basic need for today to protect green land, preserve ecological landscape and...     

Influence of aspect and location of stands on biodiversity in a Sal mixed broadleaved forest in Kumaun central Himalaya

In the present study total 21 forest stands on different aspects and locations (Hill base, mid slope and ridge top) on the slope were studied to assess the importance of these two parameters in supporting species regeneration and biodiversity in a mixed broadleaved forest between 380 and 850 m elevation in the Kumauau Himalayan region. A total of 36 tree species were recorded in the forest. In all aspects the tree, sapling and shrub richness was higher at hill base stands in comparison to mid slope and ridge top stand. Maximum tree richness (average across all aspects) was 9.7 and shrub richness was 9.3. Higher richness at hill base may be attributed to more soil moisture and deeper soils which accumulate the hill base where the slope steepness declines. The tree richness was higher in the northern aspect whereas southern aspect was more suitable for the shrub species. From the present study it becomes evident that the base of the hills can support higher biodiversity and are instrumental in supporting regeneration of several tree and shrub species in sal mixed broadleaved forest.