The ionic compositions of fine and coarse particle fractions in the two urban areas of Korea

The ionic composition of PM2.5 and PM10 was investigated using PM samples collected from Seoul and Busan during the winter of 2002. Based on the measurement data, we attempted to investigate the relative roles of different source processes in the composition of airborne particles at the two distinct urban areas. According to our measurements, the major components of both PM fractions were clearly distinguished from each other at the two different sites. It was found that the ionic concentrations in coarse fractions were generally compatible with each other at the two sites (NH(4)(+), NO(3)(-), NSSS, etc.). However, differences in their concentration levels were significant in the fine fractions and their mass concentration levels in Seoul exhibit threefold enhancement relative to Busan. The results further indicated that anthropogenic signatures were generally more evident in the fine rather than coarse fractions at both sites. However, a comparison of the coarse fraction data indicated the dominance of natural (oceanic) processes at the Busan site and conservative relationships among the different ionic components. The results of the back trajectory analysis confirmed that air mass movement patterns influence the ionic compositions of PM across different particle fractions and between different study sites.     

The latent structure of landscape perception: A mean and covariance structure modeling approach

Mean and covariance structure (MACS) modeling is used to explore a central question in contemporary environmental psychology: “How should human environments be conceptualized?”. Specifically, an expanded version of the preference model of landscape perception proposed by S. and R. Kaplan is presented. The proposed model not only constitutes a respecification and deepening of the Kaplans’ model but also presents an integrative perspective that simultaneously considers the interrelations among cognitive, motivational, affective, evaluative, and behavioral tendencies in landscape perception. In a series of four studies, we develop and validate multi-item measures of various constructs, test the measure invariances, and the structural model. The findings reveal the crucial role of various constructs that originally were hypothesized by the Kaplans but never included in the model tests. In addition, positive and negative feelings induced by the landscape emerge as antecedents to landscape perception. The implications of these findings are discussed.     

Using interview surveys and multispecies occupancy models to inform vertebrate conservation

Species distribution data are an essential biodiversity variable requiring robust monitoring to inform wildlife conservation. Yet, such data remain inherently sparse because of the logistical challenges of monitoring biodiversity across broad geographic extents. Surveys of people knowledgeable about the occurrence of wildlife provide an opportunity to evaluate species distributions and the ecology of wildlife communities across large spatial scales. We analyzed detection histories of 30 vertebrate species across the Western Ghats biodiversity hotspot in India, obtained from a large-scale interview survey of 2318 people who live and work in the forests of this region. We developed a multispecies occupancy model that simultaneously corrected for false-negative (non-detection) and false-positive (misidentification) errors that interview surveys can be prone to. Using this model, we integrated data across species in composite analyses of the responses of functional species groups (based on disturbance tolerance, diet, and body mass traits) to spatial variation in environmental variables, protection, and anthropogenic pressures. We observed a positive association between forest cover and the occurrence of species with low tolerance of human disturbance. Protected areas were associated with higher occurrence for species across different functional groups compared with unprotected lands. We also observed the occurrence of species with low disturbance tolerance, herbivores, and large-bodied species was negatively associated with developmental pressures, such as human settlements, energy production and mining, and demographic pressures, such as biological resource extraction. For the conservation of threatened vertebrates, our work underscores the importance of maintaining forest cover and reducing deforestation within and outside protected areas, respectively. In addition, mitigating a suite of pervasive human pressures is also crucial for wildlife conservation in one of the world's most densely populated biodiversity hotspots.     

Perceived Conflicts Between Pastoralism and Conservation of the Kiang Equus kiang in the Ladakh Trans-Himalaya, India

An emerging conflict with Trans-Himalayan pastoral communities in Ladakh’s Changthang Plateau threatens the conservation prospects of the kiang (Equus kiang) in India. It is locally believed that Changthang’s rangelands are overstocked with kiang, resulting in forage competition with livestock. Here, we provide a review and preliminary data on the causes of this conflict. Erosion of people’s tolerance of the kiang can be attributed to factors such as the loss of traditional pastures during an Indo-Chinese war fought in 1962, immigration of refugees from Tibet, doubling of the livestock population in about 20 years, and increasing commercialization of cashmere (pashmina) production. The perception of kiang overstocking appears misplaced, because our range-wide density estimate of 0.24 kiang km⁻² (± 0.44, 95% CL) is comparable to kiang densities reported from Tibet. A catastrophic decline during the war and subsequent recovery of the kiang population apparently led to the overstocking perception in Ladakh. In the Hanle Valley, an important area for the kiang, its density was higher (0.56 km⁻²) although even here, we estimated the total forage consumed by kiang to be only 3–4% compared to 96–97% consumed by the large livestock population (78 km⁻²). Our analysis nevertheless suggests that at a localized scale, some herders do face serious forage competition from kiang in key areas such as moist sedge meadows, and thus management strategies also need to be devised at this scale. In-depth socioeconomic surveys are needed to understand the full extent of the conflicts, and herder-centered participatory resolution needs to be facilitated to ensure that a sustainable solution for livelihoods and kiang conservation is achieved.     

Synthesis and Characterization of Low Volatile Content Polyurethane Dispersion from Depolymerised Polyethylene Terphthalate

In the past few decades, governments and international agencies have been placing more emphasis on the improvement of production technique, working conditions and reduction of the toxic emission to the atmosphere. In this context aqueous polyurethane dispersion was synthesized from depolymerised polyethylene terphthalate (PET) waste. 1,4-Butanediol was used in PET depolymerisation. Polyurethane dispersion films were characterized using differential scanning calorimeter, Fourier transform infrared spectroscopy, gel permeable chromatography, etc. Incorporation of PET waste in polyurethane dispersion was an added advantage in waste management and produced better quality polyurethane dispersion.     

Impact of linear alkyl benzene sulphonate (LAS) on phosphatase activity in testis of the teleostean fish,Heteropneustes fossilis (Bloch)

Fishes are sensitive indicators of pollutants present in water.These pollutants cause various physical and physiological alterations in fishes. In the present work alteration in the activity of acid and alkaline phosphatase was evaluated in testicular tissue of fresh water fish Heteropneustes fossilis exposed to LC50 value of linear alkyl benzene sulphonate (LAS) for different exposure periods [24 h, 48 h, 72 h and 96 h] With increase in the concentration of chemical LAS, the activity of acid phosphatase (ACP) was reported elevated while a significant fall in the activity of alkaline phosphatase (ACP) was recorded for same exposure period. Elevated activity of ACP, one of the important hydrolases of lysosomes, is quite suggestive of bringing about gross necrosis and dysarchitecture. ALP is involved in various metabolic activities including gonadal maturation and as such decreased activity of this enzyme is definitely one of the important causative factors for reproductive impairment of the fish.     

MODELING OF LEAKAGE THROUGH CRACKED CLAY LINERS -I: STATE OF THE ART1

ABSTRACT: The existence and importance of macro-pores to the containment efficiency of cover clay liners at waste landfills is documented. Macro-pores exist as voids, or cracks, and act to increase the volume and rate of leakage through cover liners. Existing numerical models used to simulate flow through clay liners are shown to neglect the macro-pore aspect of the problem. Current theories of macro-pore flow developed from related areas of research are presented, and applications to the landfill liner problem are considered.     

Influence of real and synthetic municipal solid waste leachates on consolidation and shear strength behaviour of bentonites

Environmental Science and Pollution Research - For safe disposal of wastes in landfills, compacted bentonite is recommended as bottom liners due to their significant cation exchange (CEC) and...     

Prenatal exposure to environmental pro-oxidants induces mitochondria-mediated epigenetic changes: a cross-sectional pilot study

Mitochondria play a central role in maintaining cellular and metabolic homeostasis during vital development cycles of foetal growth. Optimal mitochondrial functions are important not only to sustain adequate energy production but also for regulated epigenetic programming. However, these organelles are subtle targets of environmental exposures, and any perturbance in the defined mitochondrial machinery during the developmental stage can lead to the re-programming of the foetal epigenetic landscape. As these modifications can be transferred to subsequent generations, we herein performed a cross-sectional study to have an in-depth understanding of this intricate phenomenon. The study was conducted with two arms: whereas the first group consisted of in utero pro-oxidant exposed individuals and the second group included controls. Our results showed higher levels of oxidative mtDNA damage and associated integrated stress response among the exposed individuals. These disturbances were found to be closely related to the observed discrepancies in mitochondrial biogenesis. The exposed group showed mtDNA hypermethylation and changes in allied mitochondrial functioning. Altered expression of mitomiRs and their respective target genes in the exposed group indicated the possibilities of a disturbed mitochondrial-nuclear cross talk. This was further confirmed by the modified activity of the mitochondrial stress regulators and pro-inflammatory mediators among the exposed group. Importantly, the disturbed DNMT functioning, hypermethylation of nuclear DNA, and higher degree of post-translational histone modifications established the existence of aberrant epigenetic modifications in the exposed individuals. Overall, our results demonstrate the first molecular insights of in utero pro-oxidant exposure associated changes in the mitochondrial-epigenetic axis. Although, our study might not cement an exposure-response relationship for any particular environmental pro-oxidant, but suffice to establish a dogma of mito-epigenetic reprogramming at intrauterine milieu with chronic illness, a hitherto unreported interaction.

Graphical abstract