Quantifying the connections—linkages between land-use and water in the Kathmandu Valley,Nepal

Land development without thoughtful water supply planning can lead to unsustainability. In practice, management of our lands and waters is often unintegrated. We present new land-use, ecological stream health, water quality, and streamflow data from nine perennial watersheds in the Kathmandu Valley, Nepal, in the 2016 monsoon (i.e., August and September) and 2017 pre-monsoon (i.e., April and May) periods. Our goal was to improve understanding of the longitudinal linkages between land-use and water. At a total of 38 locations, the Rapid Stream Assessment (RSA) protocol was used to characterize stream ecology, basic water quality parameters were collected with a handheld WTW multi-parameter meter, and stream flow was measured with a SonTek FlowTracker Acoustic Doppler Velocimeter. A pixel-based supervised classification method was used to create a 30-m gridded land use coverage from a Landsat 8 image scene captured in the fall of 2015. Our results indicated that land-use had a statistically significant impact on water quality, with built land-uses (high and low) having the greatest influence. Upstream locations of six of the nine watersheds investigated had near natural status (i.e., river quality class (RQC) 1) and water could be used for all purposes (after standard treatments as required). However, downstream RSA measurements for all nine watersheds had RQC 5 (i.e., most highly impaired). Generally, water quality deteriorated from monsoon 2016 to pre-monsoon 2017. Our findings reinforce the importance of integrated land and water management and highlight the urgency of addressing waste management issues in the Kathmandu Valley.     

Adsorption of Cr(VI) by NaOH-modified microporous activated carbons derived from the wastes of Amaranthus retroflexus,Magnolia soulangeana,and Tanacetum Vulgar L.: mechanism,isotherms, and kinetic studies

Environmental Science and Pollution Research - The study was designed to synthesize microporous activated carbons from the wastes of three medicinal herbs by NaOH as an activator followed by...     

Endosulfan is toxic to the reproductive health of male freshwater fish, <Emphasis Type="Italic">Cyprinion watsoni</Emphasis>

Endosulfan is an organochlorine pesticide that is toxic to aquatic life. Endosulfan might hamper the reproductive health of indigenous fish in agricultural areas of Pakistan where this pesticide is sprayed widely. The aim of the current study is to investigate the toxic effects of endosulfan on selected reproductive parameters of male freshwater fish, Cyprinion watsoni. Two concentrations of endosulfan (0.5 and 1 ppb for 30 days exposure) were tested for their effects on body weight, body length, and testicular weight, length, and width. Testicular testosterone was assayed from tissue extracts using enzyme immunoassay (EIA). A significant increase in the mortality rate was observed in both treated groups during both spawning and quiescent seasons. The overall behavior of fish in the aquarium was normal in all control and treated groups. However, the treated fish exhibited anxiety after treatment with endosulfan. The body weight and length, and testicular weight, length and width were not significantly different to the control group. The testicular testosterone concentrations were significantly lower in both endosulfan-treated groups compared to the control. The decrease was dose-dependent, with a significant difference between the two treated groups. The histomorphological results demonstrated various testicular alterations in the treated groups. These alterations included an increase in interlobular areas and clumping patterns in spermatocytes/spermatids. Because spermatids eventually differentiate into sperms, their low count will directly result in lower sperm count. Taken together, these results suggest that endosulfan is a toxicant that at least disturbs testosterone levels (possibly others) and negatively impacts the reproductive health of male freshwater fish.     

Cool temperature performance of a wheat straw biofilter for treating dairy wastewater

A wheat straw biofilter was evaluated for attenuating pollutants in dairy (milkhouse and milking parlor) wastewater. During the 14-day study, the biofilter was operated in a sequential aerobic-anaerobic mode in a temperature range of 8-14 degrees C. While the biofilter was very effective (89% removal) in attenuating total suspended solids and moderately effective (76% removal) in attenuating oil and grease, its effectiveness in attenuating chemical oxygen demand was low (37% removal). The biofilter was ineffective in attenuating nitrate, while its effectiveness in attenuating ammonium (20% removal) and total Kjeldahl nitrogen (15% removal) was low. The biofilter was not effective in attenuating ortho-phosphate, total phosphorus, and fecal coliform. Though microbial degradation accounted for some pollutant removal, filtration seemed to be the primary mechanism. Lower temperature of operation and high oil and grease concentration (that reduced nutrient transfer to the biofilm) decreased microbial activity, reducing pollutant attenuation. Biofilter performance could be enhanced by using residual heat in the wastewater to raise the operating temperature of the biofilter and by removing oil and grease prior to applying the wastewater to the biofilter.     

Investigation of new indirect spectrophotometric method for the determination of carbofuran in carbamate pesticides

A new spectrophotometric method has been investigated for the determination of Carbofuran pesticide. The method was based on the hydrolysis of the pesticides. The hydrolyzed products, methylamine on reaction with sodium nitroprusside solution in acetone medium gives a purple colored solution. The absorbance of the resulting solution was measured at 530 nm. Conditions for the complete hydrolysis of pesticides and quantitative determination of methylamine were optimized. From the standard calibration plot of methylamine, the amount of pesticides was calculated. The amount of active ingredients in commercial products was determined from the amount of methylamine found. It was observed that lower concentration of the active ingredients were present in the commercial products. The limit of detection and quantification was calculated and found to be 0.804 and 2.68 ppm respectively.     

Potential Fluoride Contamination in the Drinking Water of Naranji Area, Northwest Frontier Province, Pakistan

The drinking water of Naranji village and surrounding areas of the NorthWest Frontier Province (NWFP), Pakistan, was analyzed for its fluoride content. The fluoride content of water samples from the springs in the Naranji village goes up to 13.52 mg kg(-1), which exceeds the permissible limit (1.5 mg kg(-1)) set by the World Health Organization (WHO). This study explores the source of fluoride contamination and attributes it to the alkaline rocks of the Ambela granitic complex and the Koga complex. The low-lying areas towards the south have a fluoride content within the permissible limit. The Naranji area therefore needs urgent remedial measures.     

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.     

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.     

Comparative distribution of the scalp hair trace metal contents in the benign tumour patients and normal donors

The scalp hair samples of benign tumour patients (n = 77) and normal donors (n = 86) were analysed for selected trace metal contents using atomic absorption spectrophotometry. In the scalp hair of benign tumour patients, highest average levels were found for Ca (1,401 microg/g), followed by Na (476.9 microg/g), Mg (441.6 microg/g), Zn (438.3 microg/g), K (119.2 microg/g) and Fe (96.38 microg/g) while in comparison, the maximum mean levels in the scalp hair of normal donors were shown by Ca (556.5 microg/g), followed by Zn (154.2 microg/g), Mg (153.4 microg/g), Na (97.45 microg/g) and Fe (81.68 microg/g). Almost all metal levels revealed higher dispersion and asymmetry in the scalp hair of benign tumour patients compared with the normal donors. The average concentrations of Ca, Cd, Co, K, Mg, Mn, Na, Ni, Pb, Sb, Sr and Zn were significantly higher in the hair of benign tumour patients compared with the normal donors. Significant gender-based differences were also observed in the scalp hair metal contents of benign tumour patients. Strong positive correlations were found between Cd-Cr (0.547) and Cd-Co (0.507) in the hair of benign tumour patients whereas Ca-Mg, Mg-Sr, Co-Cd, Cr-Cd, Li-Cr, Li-Co, Li-Cd, Na-Cd, Na-Co and Na-Li exhibited strong relationships (r > 0.50) in the hair of normal donors. Cluster analysis (CA) and principal component analysis (PCA) were used for the source identification and apportionment of scalp hair trace metals in the two donor groups. The scalp hair of benign tumour patients and normal donors revealed six and five main clusters of trace metals, respectively. PCA extracted seven principal components of trace metals in the scalp hair of benign tumour patients while six principal components were observed in the case of normal donors. The study evidenced significantly different patterns of metal distribution in the hair of benign tumour patients in comparison with normal donors.