Management of urban solid waste: Vermicomposting a sustainable option

Solid waste management is a worldwide problem and it is becoming more and more complicated day by day due to rise in population, industrialization as well as changes in our life style. Presently most of the waste generated is either disposed of in an open dump in developing countries or in landfills in the developed ones. Landfilling as well as open dumping requires lot of land mass and could also result in several environmental problems. Land application of urban/municipal solid waste (MSW) can be carried out as it is rich in organic matter and contains significant amount of recyclable plant nutrients. The presence of heavy metals and different toxics substances restricts its land use without processing. Vermicomposting of MSW, prior to land application may be a sustainable waste management option, as the vermicast obtained at the end of vermicomposting process is rich in plant nutrients and is devoid of pathogenic organism. Utilization of vermicast produced from urban/municipal solid waste in agriculture will facilitate in growth of countries economy by lowering the consumption of inorganic fertilizer and avoiding land degradation problem. Vermicomposting of urban/MSW can be an excellent practice, as it will be helpful in recycling valuable plant nutrients. This review deals with various aspects of vermicomposting of MSW.     

Ambient nitrogen oxides exposure and early childhood respiratory illnesses

Acute respiratory infections are common in children below 5 years and recent studies suggest a possible link with air pollution. In this study, we investigated the association between ambient nitrogen oxides (NO_x) and bronchitis or upper airway inflammation.This longitudinal study was conducted in Teplice and Prachatice districts, Czech Republic. Children were followed from birth to 4.5 years of age. Data were compiled from medical records at delivery and at follow up, and from self-administered questionnaires from the same two time points. Air pollution monitoring data were used to estimate exposure over five different averaging periods ranging from three to 45 days prior to an episode. To quantify the association between exposure and outcome, while accounting for repeated measure correlation we conducted logistic regression analysis using generalized estimating equations.During the first 2 years of life, the adjusted rate ratio for bronchitis associated with interquartile increase in the 30-day average NO_x was 1.31 [95% confidence interval (CI): 1.07, 1.61] and for two to 4.5 year olds, it was 1.23 (95% CI: 1.01, 1.49). The 14-day exposure also had stable association across both age groups: below 2 years it was 1.25 (95% CI: 1.06, 1.47) and for two to 4.5 years it was 1.21 (95% CI: 1.06, 1.39). The association between bronchitis and NO_x increased with child's age in the under 2 years group, which is a relatively novel finding.The results demonstrate an association between NO_x and respiratory infections that are sufficiently severe to come to medical attention. The evidence, if causal, can be of public health concern because acute respiratory illnesses are common in preschool children.     

沉积物和土壤孔隙水中甲基汞的一种新型平衡被动采样装置的研制

在这项研究中,我们探索了利用疏水性有机化学品（HOCs）开发的策略对甲基汞（MeHg）进行平衡被动采样的概念。被动取样应允许基于平衡分配到取样器中的基础上预测沉积物孔隙水（MeHgCL）中MeHg的化学不稳定部分的浓度,而无需模拟通过取样器材料的扩散速率。我们的目标是确定具有模拟甲基汞在动物和沉积物中分配的潜力的取样器材料,并在适合于原位取样器的时间框架内提供可逆吸附。测试的候选材料包括一系列嵌有合适的甲基汞吸收剂的聚合物。最有潜力的是琼脂糖包埋的活性炭（AC）、琼脂糖包埋的巯基自组装膜（SMS）和半胱氨酸功能化聚对苯二甲酸乙二醇酯（PET）,对MeHgOH和MeHg与溶解有机物（Suwannee河腐殖酸）的络合作用,测井采样器的水分配系数（Kpw）为2.8～5。沉积物中采样器的平衡时间约为1～2周。琼脂糖包埋AC对MeHg积累机制的研究表明,样品受MeHg与AC颗粒相互作用的动力学影响,而不受凝胶扩散的限制。AC显示Hg和MeHg的相对快速解吸,表明该吸附剂能够进行可逆的平衡测量。在沉积物:水的微观结构中,用等温线校准的被动取样器测得的孔隙水浓度与直接测得的浓度在2倍（未经修正的沉积物）或4倍（经修正的AC沉积物）内一致。这项工作为甲基汞的被动采样提供了一种潜在的新途径。     

Assessing the spatial variation of cropping intensity using multi-temporal Sentinel-2 data by rule-based classification

Environment, Development and Sustainability - The present study was conducted to analyze cropping intensity of four blocks (Mogra-Chinsurah, Polba-Dadpur, Singur and Haripal) of the Gangetic...     

Assessing land use change and potential environmental quality in Chandernagore Municipal Corporation,India

Environment, Development and Sustainability - The study has focused on portraying the spatio-temporal changes in land use pattern from 2011 to 2019 and has tried to assess the environmental quality...     

Performance evaluation of waste activated carbon on atrazine removal from contaminated water

In this study, the potential of spent activated carbon from water purifier (Aqua Guard, India) for the removal of atrazine (2 chloro-4 ethylamino-6-isopropylamino-1, 3, 5 triazine) from wastewaters was evaluated. Different grades of spent activated carbon were prepared by various pretreatments. Based on kinetic and equilibrium study results, spent activated carbon with a grain size of 0.3-0.5 mm and washed with distilled water (designated as WAC) was selected for fixed column studies. Batch adsorption equilibrium data followed both Freundlich and Langmuir isotherm. Fixed bed adsorption column with spent activated carbon as adsorbent was used as a polishing unit for the removal of atrazine from the effluent of an upflow anaerobic sludge blanket (UASB) reactor treating atrazine bearing domestic wastewater. Growth of bacteria on the surface of WAC was observed during column study and bacterial activity enhanced the effectiveness of adsorbent on atrazine removal from wastewater.     

Oxygen uptake in relation to group size in the juveniles of a climbing perch, Anabas testudineus (Bloch)

The present work reports oxygen uptake in relation to group size in the juveniles (body weight: 0.70 to 1.30 g) of a climbing perch, Anabas testudineus (Bloch). The experiments were conducted at 21.5 +/- 1.0 degrees C using a cylindrical glass respirometer having continuous water flow system. With an increase in the number of fish at an interval of 5 from 5 to 40 in each fourth subsequent experiment, the weight specific aquatic oxygen uptake of a fish decreased from 0.192 +/- 0.030 to 0.800 +/- 0.006 ml O2 x g(-1)x(h(-1). When compared with a controlled fish, there was a reduction of 27.80% in the oxygen uptake in a group of 5 but 58.39% in a group of 40. A negative and significant correlation (r = 0.8411, p < 0.01) was calculated between oxygen uptake and group size of fishes. The investigation showed that probably due to shoaling behaviour, the aquatic oxygen uptake in the juveniles of A. testudineus always remained high in controlled fish or a fish in isolation than when they were in a group.     

Ultrasound evaluation of pregnancies at risk for homozygous α-thalassaemia-1

Twenty-six pregnant Chinese women who were at risk of giving birth to a fetus affected with homozygous α-thalassaemia-1 were examined serially by ultrasound. Six of these 26 pregnancies were affected. In one third of the affected pregnancies progressive fetal ascites appeared before 24 weeks gestation and these pregnancies were terminated. In the remaining two thirds abnormal estimated fetal weight-placental volume (EFW-PV) ratio and fetal growth retardation as evidenced by a falling biparietal diameter (BPD), femur length (FL) but a normal abdominal circumference (AC) was apparent by 28 weeks gestation. Increased transverse cardiac (TC) diameter was another consistent finding but appeared late. All these features appeared before the onset of fetal ascites. A normal EFW-PV ratio and fetal growth until 28 weeks gestation was a reassuring sign of normality. Abnormal EFW-PV ratio was the earliest sign to appear in affected pregnancies and a normal ratio until 28 weeks gestation had a 100 per cent predictive value.