Increase in NO_<i>x</i> Emissions from Indian Thermal Power Plants during 1996–2010: Unit-Based Inventories and Multisatellite Observations

Driven by rapid economic development and growing electricity demand, NO_<i>x</i> emissions (<i>E</i>) from the power sector in India have increased dramatically since the mid-1990s. In this study, we present the NO_<i>x</i> emissions from Indian public thermal power plants for the period 1996–2010 using a unit-based methodology and compare the emission estimates with the satellite observations of NO₂ tropospheric vertical column densities (TVCDs) from four spaceborne instruments: GOME, SCIAMACHY, OMI, and GOME-2. Results show that NO_<i>x</i> emissions from Indian power plants increased by at least 70% during 1996–2010. Coal-fired power plants, NO_<i>x</i> emissions from which are not regulated in India, contribute ∼96% to the total power sector emissions, followed by gas-fired (∼4%) and oil-fired (<1%) ones. A number of isolated NO₂ hot spots are observed over the power plant areas, and good agreement between NO₂ TVCDs and NO_<i>x</i> emissions is found for areas dominated by power plant emissions. Average NO₂ TVCDs over power plant areas were continuously increasing during the study period. We find that the ratio of Δ<i>E</i>/<i>E</i> to ΔTVCD/TVCD changed from greater than one to less than one around 2005–2008, implying that a transition of the overall NO_<i>x</i> chemistry occurred over the power plant areas, which may cause significant impact on the atmospheric environment

Ozone Monitoring Instrument Observations of Interannual Increases in SO₂ Emissions from Indian Coal-Fired Power Plants during 2005–2012

Due to the rapid growth of electricity demand and the absence of regulations, sulfur dioxide (SO₂) emissions from coal-fired power plants in India have increased notably in the past decade. In this study, we present the first interannual comparison of SO₂ emissions and the satellite SO₂ observations from the Ozone Monitoring Instrument (OMI) for Indian coal-fired power plants during the OMI era of 2005–2012. A detailed unit-based inventory is developed for the Indian coal-fired power sector, and results show that its SO₂ emissions increased dramatically by 71% during 2005–2012. Using the oversampling technique, yearly high-resolution OMI maps for the whole domain of India are created, and they reveal a continuous increase in SO₂ columns over India. Power plant regions with annual SO₂ emissions greater than 50 Gg year^–1 produce statistically significant OMI signals, and a high correlation (<i>R</i> = 0.93) is found between SO₂ emissions and OMI-observed SO₂ burdens. Contrary to the decreasing trend of national mean SO₂ concentrations reported by the Indian Government, both the total OMI-observed SO₂ and annual average SO₂ concentrations in coal-fired power plant regions increased by >60% during 2005–2012, implying the air quality monitoring network needs to be optimized to reflect the true SO₂ situation in India

Characteristics of homology search of unigenes against the NR database.

<p>(A) E-value distribution of the top BLAST hits for each unigene with a cut-off E-value of 1.0E−5. (B) Similarity distribution of the best BLAST hits for each unigene. (C) Species distribution is shown as the percentage of the total homologous sequences with an E-value of at least 1.0E−5. We used all plant proteins in the NCBI NR database for homology search and extracted the first hit of each sequence for analysis.</p

Virus induced local lesions on leaves of <i>C. amaranticolor</i>.

<p>(A) The 6-week old plant of <i>C. amaranticolor</i>. (B) Leaves inoculated with <i>Tobacco mosaic virus</i> at 40 hours p.i.. (C) Leaves inoculated with <i>Cucumber mosaic virus</i> at 40 hours p.i.. Scale bar = 1.0 cm.</p

De Novo Foliar Transcriptome of <em>Chenopodium amaranticolor</em> and Analysis of Its Gene Expression During Virus-Induced Hypersensitive Response

<div><h3>Background</h3><p>The hypersensitive response (HR) system of <em>Chenopodium</em> spp. confers broad-spectrum virus resistance. However, little knowledge exists at the genomic level for <em>Chenopodium</em>, thus impeding the advanced molecular research of this attractive feature. Hence, we took advantage of RNA-seq to survey the foliar transcriptome of <em>C. amaranticolor</em>, a <em>Chenopodium</em> species widely used as laboratory indicator for pathogenic viruses, in order to facilitate the characterization of the HR-type of virus resistance.</p> <h3>Methodology and Principal Findings</h3><p>Using Illumina HiSeq™ 2000 platform, we obtained 39,868,984 reads with 3,588,208,560 bp, which were assembled into 112,452 unigenes (3,847 clusters and 108,605 singletons). BlastX search against the NCBI NR database identified 61,698 sequences with a cut-off E-value above 10⁻⁵. Assembled sequences were annotated with gene descriptions, GO, COG and KEGG terms, respectively. A total number of 738 resistance gene analogs (RGAs) and homology sequences of 6 key signaling proteins within the R proteins-directed signaling pathway were identified. Based on this transcriptome data, we investigated the gene expression profiles over the stage of HR induced by <em>Tobacco mosaic virus</em> and <em>Cucumber mosaic virus</em> by using digital gene expression analysis. Numerous candidate genes specifically or commonly regulated by these two distinct viruses at early and late stages of the HR were identified, and the dynamic changes of the differently expressed genes enriched in the pathway of plant-pathogen interaction were particularly emphasized.</p> <h3>Conclusions</h3><p>To our knowledge, this study is the first description of the genetic makeup of <em>C. amaranticolor</em>, providing deep insight into the comprehensive gene expression information at transcriptional level in this species. The 738 RGAs as well as the differentially regulated genes, particularly the common genes regulated by both TMV and CMV, are suitable candidates which merit further functional characterization to dissect the molecular mechanisms and regulatory pathways of the HR-type of virus resistance in <em>Chenopodium</em>.</p> </div

Effect of query length on the percentage of significant matches.

<p>(A) Singleton sequences. (B) Cluster sequences. The proportion of sequences with matches (with a cut-off E-value of 1.0E−5) in NR databases is greater among the longer assembled sequences.</p

GO categories of biological process, cellular component and molecular function for the foliar transcriptome of <i>C. amaranticolor</i>.

<p>The right y-axis shows the number of genes in a category, while the left y-axis indicates the percentage of a specific category of genes in that main category.</p

Statistics of DGE sequencing data from <i>C. amaranticolor</i> infected with distinct viruses.

a<p>The reads were mapped to foliar transcriptom of <i>C. amaranticolor</i> with 112, 452 unigenes.</p>b<p>The conservative degree of mismatch was no more than 2 bp.</p