Search

The adverse impact of climate change on crop yield has accelerated the need for identification of crop cultivars resistant to abiotic stress. In the present study, a cultivar assortment index (CAI) was generated for the evaluation of forty Amaranthus hypochondriacus cultivars response to elevated ozone (EO) concentrations (AO + 30 ppb) in Free Air Ozone Enrichment (FAOE) facility using the parameters viz. foliar injury, gaseous exchange attributes, namely, net photosynthetic rate, stomatal conductance, transpiration rate, intercellular carbon dioxide, and water use efficiency along with above ground biomass and grain yield attributes. The dataset was used to identify key indicator parameters responsive to EO through principal component analysis (PCA) and further transformed to obtain linear score and weighted score. The CAI varied from 70.49 to 193.43. Cultivars having CAI value less than 151 were ozone tolerant (OT) whereas cultivars with CAI values between 150 and 170 were moderately tolerant (MOT). The cultivars exhibiting CAI values above 170 were ozone sensitive (OS). The cultivars exhibited differential sensitivity to EO with IC-5994 (CAI = 187.26) being the most affected cultivar whereas IC-5576 (CAI = 83.38) and IC-5916 (CAI = 70.49) being the least affected ones. The CAI, based on linear score and weighted score, offers easy identification of ozone sensitive (OS) and ozone tolerant (OT) cultivars. This index could help researchers to define a clear and strong basis for identification of OT cultivars which will reduce the time required for preliminary screening and further evaluation of crop cultivars for the development of climate smart crops.

The present study was conducted to assess the response of thermotolerant wheat cultivar (Triticum aestivum L. var. WR544) to individual and combination of ambient ground level ozone (AO3) and particulate matter (PM) air pollutants with ethylene diurea (EDU) used as an ozone stress mitigator. The four treatment combinations to which wheat cultivars were exposed are T1 (AO3 + PM), T2 (EDU + PM), T3 (AO3-PM), and T4 (EDU-PM). The effect of different treatments on morphological (foliar ozone injury, leaf area, shoot height, number of leaves, and total biomass), biochemical (leaf extract pH, electrical conductivity, relative water content, total chlorophyll, ascorbic acid content), nutritional (leaf carbohydrate content and leaf protein content), and yield (biological yield, economic yield, and harvest index) attributes of the cultivar were monitored. The plants under T1 experienced 20–30% foliar ozone injury and recorded lowest economic yield (0.58 g/plant). Plants under T2 and T3 showed visible foliar ozone injury range between 0 and 5% whereas plants under T4 exhibited negligible ozone injuries. EDU-treated plants without PM deposition (T4) exhibited better morphology, leaf protein content, leaf carbohydrate content, biological and economic yield as compared to T1-, T2-, and T3-treated plants but EDU was only partially effective. Despite being a thermotolerant variety, WR544 gets adversely affected by the individual and combined exposure of AO3 and PM air pollutants. These result findings highlighted the need for more detailed study of air quality impact on the thermotolerant cultivars of other key crops to individual and combined air pollutants.

The original article has been published inadvertently with some errors in Table 6—the last sentence of the abstract and the last sentence after Eq. (2) (581 mm). The corrected Table 6 is given below."

Pollutants are important determinants of respiratory morbidity. This study endeavours to explore the roleof vegetation in air quality improvement. The 24 hour average of prevailed ambient levels of air pollutants,(PM2.5), (NO2) and (NO) at four sites of Delhi were recorded. The abundance, frequency and density ofvegetation was assessed using belt transect method. Software i- Tree Canopy was used to assess the amountof pollution removal and carbon sequestration potential by vegetation. Results indicate that Pusa hadhighest abundance (6.7), frequency (86%) and density (6.2) of vegetation as compared to Dwarka, Rohiniand ITO sites. ITO had minimum abundance (2.0), frequency (50%) and density (1.9) of vegetation. Thecorrelation between the abundance, frequency and density of vegetation and ambient levels of air pollutantswas negative. The i-tree software indicates that the potential of vegetation in removing the load of airpollutants was significant. The quantity NO2 and PM2.5 removed by vegetation of Pusa, Dwarka, Rohiniand ITO sites were 331.2g and 128.5g; 117.7g and 46.4g; 67.6g and 26.6g and 37.6g and 15g respectively.The carbon sequestration potential was maximum (520Kg in year) and minimum (60.2Kg in year) at Pusaand ITO respectively. Regression equations were accordingly computed, which could predict the potentialpollution removal with vegetation. Objective evidence based estimation of potential reduction of pollutantswith planting trees, has important implications on public health.

The study was conducted with an aim to provide practical solution for the groundwater management in three villages namely Singhola, Ghoga and Dhirpur of the North-West Delhi, India. LANDSAT remote-sensing datasets for the last four decades (1977–2018) were assessed to determine changes in vegetation cover at the selected sites. The Google Earth Engine was used to determine how values of the Normalized Difference Vegetation Index (NDVI) were found to have varied spatially and over time for the selected sites. Strong correlations were found between the NDVI values of surface features including waterbodies, forest land, agricultural land and urban areas in Singhola, Ghoga and Dhirpur, respectively. The relative infiltration capacity of soils was highest (92.9%) and lowest (57%) for Singhola and Dhirpur, respectively, due to spatial differences in soil texture. In each village, locations exhibiting a higher soil infiltration capacity could be used for implementing managed aquifer recharge schemes using rainwater harvested from rooftops in the villages. This assessment indicated that the village of Ghoga has the highest potential (3,76,98,013.08 m3) for aquifer recharge through rooftop rainwater harvesting as compared to the other two villages.

Indoor Air Quality (IAQ) is considered to be of great concern due to its adverse impact on the human health nowadays. The presence of different air pollutants along with noise may aggravate the IAQ. The present study attempts to examine IAQ in terms of major criteria air pollutants (O3, NOx=NO+NO2, CO and PM2.5) along with total volatile organic compound (TVOC), individual VOC and noise pollution in indoor and outdoor environment of a Commercial Shopping Complex (CSC) in Delhi. Real time measurements have been carried out for O3, NOx, CO, PM2.5, TVOC and noise while thirteen individual VOCs have been estimated using NIOSH method was performed using Gas Chromatograph. The study also aimed to find out the relationship among VOCs, source estimation using Principal Component Analysis. The observed results for the targeted pollutants were also compared with international and national recommended permissible values. The mean values of O3, NOx, CO, PM2.5 and TVOC are found to be 17.6/(15.0) ppb, 15.8/(14.1) ppb, 8.4/(1.9) ppm, 125.4/(74.6) μg/m3 and 412.5/(226.5) μg/m3 for indoor/(outdoor), respectively. Among the individual VOC, toluene was the most abundant followed by xylene-isomers and benzene. The noise pollution level in Indoor/outdoor were found to be 51.5/46.4dB which is below the guideline value (65dB) provided by the WHO. Most of the pollutants were found to have indoor sources. The different kinds of pollutants and noise may have synergistic effect and aggravate the health of the people working and visiting the CSC.

The present study deals with the concentrations of individual and total volatile organic compounds (TVOCs) present in the ambient atmosphere of Delhi. Sampling was done in four different zones, viz. residential, commercial, industrial and heavy traffic density area (HTDA) during rush and non-rush hours. The National Institute for Occupational Safety and Health (NIOSH)-1501 standard method was used for benzene, toluene, ethylbenzene and xylene (BTEX) measurements while real-time monitoring was done for TVOC using a data-logging photoionization detector. Results showed that the mean concentrations of TVOC and ∑BTEX were found to be highest in HTDA as compared to those in other zones. Toluene contributed the most among BTEX as 28.5, 108.6, 129.6 and 104.5 μg/m3 at residential, commercial, industrial and HTDA, respectively. However, the concentrations of TVOC were found to be 518.9 μg/m3 in HTDA followed by industrial (511.3 μg/m3), commercial (429.6 μg/m3) and residential areas (199.5 μg/m3). It is noted that the concentrations of the pollutants were observed to be higher during rush hours in contrast to non-rush hours due to more number of vehicles plying the road. After examining the seasonal variability, the winter samples showed the highest concentrations of the pollutants which could be due to stable environment. In order to identify the sources, characteristic ratios and correlation analysis were also done. Cancer and non-cancer risks were estimated for BTEX using US Environmental Protection Agency (USEPA) guidelines. The estimated lifetime cancer risk (LCR) in this study exceeded the value of 1.0 × 10−6 recommended by the USEPA for adults and children in all zones. The population groups are in the category of “possible risk” after comparing with the Sexton’s classifications of cancer risk.

Water, carbon (C) and nitrogen (N) are important natural resources required for crop production. Footprints of these three natural resources are useful indicators of consumption and pollution. The present project is aimed to determine the water, carbon and nitrogen footprints of major crops of the Indo-Gangetic Plains (IGPs). Field experiments were conducted, and modelling tools were used to quantify water, C and N footprints of rice and wheat crops in IGP. Four locations (Karnal, Delhi, Varanasi and Kalyani) were selected for the study representing different transects of IGP. Carbon footprint (CFP) of rice crop in Karnal and Delhi was found to be higher than Varanasi and Kalyani due to application of more amounts of agri-inputs and more use of farm machineries leading to higher GHG emission. Although GHG emission in wheat is also more in Karnal, higher yield of wheat crop led to lower CFP than Varanasi. Water footprint (WFP) of rice production was higher in Karnal, Delhi and Varanasi than Kalyani region mainly due to higher evapotranspiration. QGIS software was used to prepare geospatial maps of carbon and water footprint for IGP. The study will help in identifying regions and crops having higher footprints and also select alternative management practices which will help in lowering water, C and N footprints of agricultural production.

The present study endeavours to explore the role of vegetation in air quality improvement at selected sites of Delhi. The study was conducted at four sites of Delhi-Pusa in Central Delhi, ITO in East Delhi, Dwarka in South West Delhi and Rohini in North West Delhi. To monitor and quantify the abundance, frequency and density of vegetation of the sites,belt transect method (with 500m transect and 30 quadrats of 0.5 x 0.5m) was used. Results of the study indicate that Pusa had highest abundance(6.7), frequency(86%) and density(6.2) of vegetation as compared to Dwarka, Rohini and ITO. ITO site has minimum abundance (2.0), frequency (50%) and density (1.9) of vegetation. There was a statistically negative correlation between the abundance, frequency and density of vegetation and ambient levels of chemical air pollutants. Physical pollutant (PM 2.5 ), doesn’t seem to get affected by vegetation. The study indicates that the contribution of vegetation is significant in improving air quality of urban areas.

Monoterpene emission samples of 50 Indian plant species were collected using a dynamic flow–through enclosure chamber technique and concentrations were determined with the help of GC–FID/MS. Monoterpene emission rates of different plant species ranged from negligible to 16.9 µg g –1 h –1 . Thirty four of the screened fifty plant species, were found to be monoterpene emitters. Volatile organic compound (VOC) emission capacity of predominantly plantation forest of Haryana was also estimated, which was found to be 20.9 mg C m –2 h –1 . Individual plant species area averaged VOC emission capacity ranged from negligible to 12.0 mg C m –2 h –1 . Dalbergia sisoo and Eucalyptus globulus , were found to contribute approximately 82% of the total VOC emission capacity.