Modeling of agricultural drought risk pattern using Markov chain and GIS in the western part of Bangladesh

The aim of the study is to assess the agricultural drought risk condition in the context of global climate change in the western part of Bangladesh that covers about 45% area of the country for the period of 1960–2011. Drought Index (DI) and Drought Hazard Index (DHI) have been calculated by Markov Chain analysis and that of Drought Vulnerability Index (DVI) from socioeconomic and physical indicators. The DI values show that the northern part in general is more drought-prone, having less crops prospect, whereas the southern part is less drought-prone with high crop potentiality. The probability of extreme drought occurrence increases in recent decades in some parts as a result the drought events become more frequent in the areas. The DHI ranges from 15 to 32, and northern part suffers from more extreme drought hazards than that of southern part. DVI also indicates that northern part is exposed to high to very high drought vulnerability as higher percentage of illiterate people are involved in agricultural practices and high percentage of irrigation to cultivable land, but southern part exposed to moderate to low vulnerability because of low values of vulnerability indicators. Finally, agricultural drought exists at high risk condition in northern part and low in southern parts and 21.63, 26.54 and 29.68% of the area poses very high, high and moderate risk, respectively. So, immediate adaptation measures are needed keeping in mind climate features like rainfall and temperature variability, drought risk and risk ranking to make viable adaptation measures.     

Analyzing temporal–spatial characteristics of drought events in the northern part of Cyprus

Drought in the northern part of Cyprus has become a recurrent phenomenon. In the last few decades, Cyprus has experienced significantly severe drought events occurring periodically, and this trend is now continuing. With rainfall distribution varying considerably across the region and frequent drought conditions, the water resources, agriculture, economy and the environment have been adversely affected. This study aims to investigate spatial–temporal characteristic of drought using Standardized Precipitation Index (SPI) at multiple timescales (3, 6 and 12 months). Monthly time series of 36 years (1977–2013) rainfall data from nine weather stations are used to derive SPI values. Based on different drought categories, this study focuses on propagation of drought from one timescale to another and estimating critical rainfall values during moderate, severe and extreme drought conditions. The analysis revealed that there is a strong correlation among different timescales in detecting drought events. On average, 79 and 78% of 3-month timescale drought propagated into 6- and 12-month drought events, respectively, while 90% of 6-month timescale drought events propagated into 12-month drought events. The derived critical rainfall value for extreme droughts over a 12-month timescale was less than 255 mm/year in the town of Alsancak, while for Guzelyurt, a major citrus growing city, this figure was less than 135 mm/year. The results are validated through drought events detected at various regions of the Mediterranean basin and local flood occurrences during the wet periods and decline in water tables at drought seasons.     

Comparative Analysis of Variation in Ecological Forms of Altai Osman, <Emphasis Type="Italic">Oreoleuciscus potanini</Emphasis> (Cyprinidae), in Lakes Ayrag,Khyargas, and Nogon (Western Mongolia)

Analysis of variation in morphological characters of Potanin Altai osman, Oreoleuciscus potanini, from two freshwater and one brackish water lakes of Western Mongolia has shown that specimens of different ecological forms—herbivorous and piscivorous—form two integral and, at the level under consideration, internally indivisible units in the system of phenetic diversity of the species O. potanini.     

Traffic and outdoor air pollution levels near highways in Baghdad,Iraq

In Iraq, the number of passenger cars, trucks and buses, local generators, and heavy construction equipment rose to a considerable extent since 2003, causing high environmental problems. Many types of pollutants were monitored and recorded for 24 h during March 2016. The study attempts to explore and establish a relationship between the volume of activity and the movement of motor vehicles of various compounds and contaminants resulting from their exhaust pipes, such as sulfur dioxide, particulate matters, oxides of nitrogen, VOCs, and unburned hydrocarbons. The study focused in and around Mohammad Al-Qasim highway adjacent to the University of Technology, Baghdad. The results showed the need for urgent treatments addressed by the environmental authorities in the city. The study results demonstrated that these contaminants are increased during periods of the beginning and end of working hours for government departments. Some types of sulfur compounds (H₂S and SO₂) concentrations were at serious health-threatening levels, which is a result of the high sulfur content in the Iraqi fuel. The concentrations of NOx and VOC were high, also, which could make the studied area vulnerable to the risk of smog formation. The Iraqi government should make greater efforts to protect the environment and human in this country from the transportation pollution risks.     

低温等离子体与絮凝剂处理印染废水的协同效应

采用低温等离子体和絮凝剂协同处理印染废水.结果表明,染料废水脱色率和COD去除率随输入电压增大和放电时间延长而增加;电极间距、废水初始浓度、通入空气流量等因素对印染废水处理效果也有很大影响;气相中放电效果优于液相中放电,阳极电极在液面以上8mm左右时放电效果最好,在其他条件不变情况下随废水初始浓度和通入空气流量增大废水脱色和COD脱除率先增大再减小,有一最佳峰值.印染废水先经过等离子体处理后再加入絮凝剂处理效果优于先加絮凝剂后放电、仅有等离子体放电的过程.在本实验中初始浓度200mg/L(CODCr初始值572)印染废水在外加电压40kV、放电时间20min、电极间距8mm、通入空气流量16L/h条件下,与絮凝剂PAC相互协同作用可达到96%脱色率、63%COD去除率.     

Framing of Geoengineering Affects Support for Climate Change Mitigation

The growing recognition that climate change mitigation alone will be inadequate has led scientists and policymakers to discuss climate geoengineering. An experiment with a US sample found, contrary to previous research, that reading about geoengineering did not reduce conservatives’ skepticism about the existence of anthropogenic climate change. Moreover, depending on how it is framed, geoengineering can reduce support for mitigation among both conservatives and non-conservatives. When geoengineering is framed as a major solution, people worry less about climate change, leading to reduced mitigation support. When framed as disastrous, people perceived geoengineering as riskier, also leading to a decrease in mitigation support. A more moderate framing of geoengineering as a partial solution is less susceptible to moral hazard effects. Overall, results suggest that geoengineering will not lessen political polarization over anthropogenic climate change, and could undercut support for mitigation efforts. Instead, framing geoengineering as a small piece to solving a big puzzle seems to be the best strategy to weaken this potential moral hazard.     

The Effect of Vaccinium vitis-idaea on Properties of Mountain-Meadow Soil under Alpine Lichen Heath

Russian Journal of Ecology - Abstract—The study of the effect of mycorrhiza symbiosis on the transformation of carbon and nitrogen compounds in soils is important in view of the necessity to...     

Status of air pollution in Beijing

A study has been made on elements organic constituents, TSP, SO2,NO2 of atmospheric pollutants in Beijing. 17 elements, and some PAHs, e. g. B(a)P, B(b, j, k)P, and B(g, h, i)P, in airborne particles by X-ray fluorescence spectroscopy and HPLC, GC/MS, have been determined respectively. It has been shown that the elements Pb, Zn, S and Cu were more enriched in fine particles and different valence states of sulfur at various sites. It was found that the concentrations of S6+ and S2-were more than 85% and less than 15% of the total sulfur respectively. Concentrations of major PAHs and sulfur-containing compounds increased in winter and in urban area. High values for Pb and Zn in city, Fe and Mn at industrial area and Cu, Al rural sites were obtained respectively. This implies the functions of different elemental sources of various sites. Thus, elements can be from distingushed anthropogenic and natural sources.The main contribution of SO2 was found of to have same seasonal variation as the anthropogenic el     

The stable isotope signature of methane emitted from plant material under UV irradiation

Recent experiments have shown that dry and fresh leaves, other plant matter, as well as several structural plant components, emit methane upon irradiation with UV light. Here we present the source isotope signatures of the methane emitted from a range of dry natural plant leaves and structural compounds. UV-induced methane from organic matter is strongly depleted in both ¹³C and D compared to the bulk biomass. The isotopic content of plant methoxyl groups, which have been identified as important precursors of aerobic methane formation in plants, falls roughly halfway between the bulk and CH₄ isotopic composition. C3 and C4/CAM plants show the well-established isotope difference in bulk ¹³C content. Our results show that they also emit CH₄ with different δ¹³C value. Furthermore, δ¹³C of methoxyl groups in the plant material, and ester methoxyl groups only, show a similar difference between C3 and C4/CAM plants. The correlation between the δ¹³C of emitted CH₄ and methoxyl groups implies that methoxyl groups are not the only source substrate of CH₄.Interestingly, δD values of the emitted CH₄ are also found to be different for C3 and C4 plants, although there is no significant difference in the bulk material. Bulk δD analyses may be compromised by a large reservoir of exchangeable hydrogen, but no significant δD difference is found either for the methoxyl groups, which do not contain exchangeable hydrogen. The δD difference in CH₄ between C3 and C4 plants indicates that at least two different reservoirs are involved in CH₄ emission. One of them is the OCH₃ group, the other one must be significantly depleted, and contribute more to the emissions of C3 plants compared to C4 plants. In qualitative agreement with this hypothesis, CH₄ emission rates are higher for C3 plants than for C4 plants.     

Solar driven nitrous acid formation on building material surfaces containing titanium dioxide: A concern for air quality in urban areas?

The photoenhanced uptake of nitrogen dioxide (NO₂) to the surface of commercially available self-cleaning window glass has been studied under controlled laboratory conditions. This material is one of an array of modern building products which incorporate titanium dioxide (TiO₂) nanoparticles and are finding increasing use in populated urban areas. Amongst the principal drivers for the use of these materials is that they are thought to facilitate the irreversible removal of pollutants such as NO₂ and organic molecules from the atmosphere and thus act to remediate air quality. While it appears that TiO₂ materials do indeed remove organic molecules from built environments, in this study we show that the photoenhanced uptake of NO₂ to one example material, self-cleaning window glass, is in fact accompanied by the substantial formation (50–70%) of gaseous nitrous acid (HONO). This finding has direct and serious implications for the use of these materials in urban areas. Not only is HONO a harmful respiratory irritant, it is also readily photolysed by solar radiation leading to the formation of hydroxyl radicals (OH) together with the re-release of NO_x as NO. The net effect of subsequent OH initiated chemistry can then be the further degradation of air quality through the formation of secondary pollutants such as ozone and VOC oxidation products. In summary, we suggest that a scientifically conceived technical strategy for air quality remediation based on this technology, while widely perceived as universally beneficial, could in fact have effects precisely opposite to those intended.