Fortress of Culture: Reinterpreting Krobo Mountain Site Through the Perspective of Persistent Places

Tree-ring records from remote upland areas are widely used in climate reconstructions, but they are typically calibrated by meteorological data from low-lying areas. With the aim of assessing relationships between climatic records from mountainous and valley bottoms, this study compared meteorological records between mountainous sites (lower to upper elevations) and valley bottoms (Qilian (QL) and Yeniugou (YNG)) in the upper reaches of the Heihe River, northwestern China. We found that daily, 5-day, 10-day, and monthly mean air temperatures observed during a 4-year observational period in valley bottoms were strongly correlated (R = 0.90–0.99) to their mountainous site counterparts. Additionally, temperature records from the QL meteorological station shared a higher percentage of variance with each mountainous site compared to YNG. Correlations of precipitation totals between valley bottoms and mountainous sites showed a similar pattern to temperatures. Furthermore, different time series of total rainfall in YNG can explain more variance than those from QL and were also more suitable representations of mountainous sites. Our results confirmed the reliability of utilizing monthly climatic records from valley bottoms to calibrate tree-ring records in mountainous sites. We also caution that when conducting fine-scale microcoring and dendrometer monitoring studies, lower correlations of short-term scale precipitation records between valley bottoms and mountainous sites may introduce unavoidable errors.

Burning of the soils as a result of the burning of vegetation especially the forests are often due to human activities. Most zones which are affected with burning are arid and semi-arid regions. Libya is one of arid regions in the world because the annual rainfall does not exceed 650 mm per year except in a small area called Green mountain (Aljabal Alakhdar), which is receive an annual rainfall exceed than 400 mm. It is the only wet area in Libya, so it contains forest with plant diversity. This region (the area covered by this study), like any forest area in the Mediterranean region is exposed to encroachments such as burning parts of it to convert trees to charcoal or burning trees and turning them into agricultural land in other parts. Therefore, the aim of this study was to evaluate the effects of burning on the organic matter, chemical macro nutrients: total nitrogen, total phosphorus and exchangeable potassium that following burning in two areas in the Green Mountain, with those exposed to burning compared to those in adjacent unburned areas in one seaboard (Ras alhelal) and one mountainous (Marawah) site. The results of this study indicated that the soils in both sites, regardless of burning or depth fall into the silt loam category texture and the main separated particle size was the silt with low clay contents, also the results indicated that, the fire was not enough to change this texture. In the light of the results obtained, it is clear that soils of both study sites are characterized by low organic matter content. In addition, the results indicate that the average percentage of the organic matter in all layers at the seaboard site was higher than its average percentage in the equivalent layers at the mountainous site. According to the findings obtained from this study, there has been a strong impact of fire on total N especially in the new burnt (mountainous) site, which agrees reasonably well with the degrees of soil organic matter of both burned study sites. The expected way that total N would be lost in these soils by fire is in volatilization and particulate transfer to the atmosphere during burning. The results of total P in soils showed that there was more total P in the upper soil layer in the old-burnt site (seaboard) than the new-burnt (mountainous) site at the same depth. It should be noticed from the data that the amount of total P in the seaboard site was high compared with its amount in the mountainous site. As well the results showed that, exchangeable potassium was very limited probably due to its absence in the parent material of the soils and almost all that there is being absorbed by plants. The results indicate that the highest quantities of the exchangeable potassium were in the uppermost layers in both study sites, were particularly high in the mountainous site compared with the seaboard site and were markedly affected by burning in the top layer of the soil.

Concentrations of atmospheric culturable bioaerosols at mountain and seashore sites were measured in field investigations by using a bio-culture sampler. The eastern Korean peninsula was selected for the measurements because of the short distance between the mountain site and the seashore site. Detectable concentrations of culturable fungal and bacterial bioaerosols (maximum 1065 CFU/m3) were quantitatively measured at the mountain and seashore sites. In addition, measurement of bioaerosols was conducted at an urban area as reference data. Significantly higher concentrations of bioaerosols were found at the mountain site. However, several fold smaller levels of bioaerosols were detected at the seashore site (t-test p-value < 0.05).

As intermediate products of photochemical reactions, alkyl nitrates (RONO2) regulate ozone (O3) formation. In this study, a photochemical box model incorporating master chemical mechanism well reproduced the observed RONO2 at an urban and a mountainous site, with index of agreement in the range of 0.66–0.73. The value 0.0003 was identified to be the most appropriate branching ratio for C1 RONO2, with the error less than 50%. Although levels of the parent hydrocarbons and nitric oxide (NO) were significantly higher at the urban site than the mountainous site, the production of C2–C3 RONO2 was comparable to or even lower than at the mountainous site, due to the lower concentrations of oxidative radicals in the urban environment. Based on the profiles of air pollutants at the mountainous site, the formation of C2–C4 RONO2 was limited by NOx (volatile organic compounds (VOCs)) when total volatile organic compounds (TVOCs)/NOx was higher (lower) than 10.0 ± 0.4 parts per billion by volume (ppbv)/ppbv. This dividing ratio decreased (p &lt; 0.05) to 8.7 ± 0.4 ppbv/ppbv at the urban site, mainly due to the different air pollutant profiles at the two sites. For the formation of C1 RONO2, the NOx‐limited regime extended the ratio of TVOCs/NOx to as low as 2.4 ± 0.2 and 3.1 ± 0.1 ppbv/ppbv at the mountainous and urban site, respectively. RONO2 formation led to a decrease of simulated O3, with reduction efficiencies (O3 reduction/RONO2 production) of 4–5 parts per trillion by volume (pptv)/pptv at the mountainous site and 3–4 pptv/pptv at the urban site. On the other hand, the variations of simulated O3 induced by RONO2 degradation depended upon the regimes controlling O3 formation and the relative abundances of TVOCs and NOx.

Atmospheric PAHs, NPAHs, and OPAHs at an urban, mountainous, and marine sites in Northern China: Molecular composition, sources, and ageing

Study on the characteristics of urban background ozone pollution based on long-term observations from mountain sites in China during 2015–2022

Unraveling ozone formation sensitivity to ambient VOCs and NOx at urban and mountain sites in a typical city of eastern China.

Source categories and contribution of biomass smoke to organic aerosol over the southeastern Tibetan Plateau

Transportation is one of the main causes of atmospheric pollution, especially in downtown big cities. Researchers usually point their attention to gaseous and/or particulate matter pollutants. This paper investigated the role of submicron particles, particularly the fraction ranging between 5–560 nm, in aerosol chemistry for identifying the contribution of autovehicular traffic and investigating the doses deposited in the human respiratory tract. Measurements carried out by two Fast Mobility Particle Sizer (FMPS, TSI) analyzers were simultaneously performed at two different sampling sites (an urban and a mountain site) during workdays and weekends in July. The total particle number (2–2.5 times higher in the urban site), the aerosol size distribution (different modes during the day), and the ultrafine/non-ultrafine particle ratios (ranging between 2–4 times between two sites) were investigated and discussed in relationship to the high autovehicular traffic in Rome and the almost null anthropogenic emissions at the mountain site, as well as the differing contributions of both to the “fresh nucleation” and to “aged aerosol”. Furthermore, the regional cumulative number doses deposited in the human respiratory tract were studied for both sites: The difference between the urban/mountain site was very high (up to 15 fold), confirming the pollutant role of transportation.

A method to determine rainwater solutes from pH and conductivity measurements

Concentrations of various size fractions (TSP, PM10, PM2.5, and PM1.0) of particulate matter (PM) were measured at two mountainous sites, Buk Han (BH) and Gwan AK (GA), along with one ground reference site at Gwang Jin (GJ), located in Seoul, South Korea for the 4years from 2010 to 2013. The daily average concentrations of TSP, PM10, PM2.5, and PM1.0 at BH were 47.9±32.5, 37.0±24.6, 20.6±12.9, and 15.3±9.53μgm(-3), respectively. These values were slightly larger than those measured at GA while much lower than those measured at the reference site (GJ). Seasonal variations in PM concentrations were consistent across all locations with a relative increase in concentrations observed in spring and winter. Correlation analysis showed clear differences in PM concentrations between the mountainous sites and the reference site. Analysis of these PM concentrations indicated that the distribution of PM in the mountainous locations was affected by a number of manmade sources from nearby locations, including both traffic and industrial emissions.

Biotic communities and environmental conditions can be highly variable between natural ecosystems. The variability of natural assemblages should be considered in the interpretation of any ecological study when samples are either spatially or temporally distributed. Little is known about biotic variability in the Santa Ana River Basin. In this report, the lotic community and habitat assessment data from ecological studies done as part of the U.S. Geological Survey’s National Water-Quality Assessment (NAWQA) program are used for a preliminary assessment of variability in the Santa Ana Basin. Habitat was assessed, and benthic algae, benthic macroinvertebrate, and fish samples were collected at four sites during 1999–2001. Three of these sites were sampled all three years. One of these sites is located in the San Bernardino Mountains, and the other two sites are located in the alluvial basin. Analysis of variance determined that the three sites with multiyear data were significantly different for 41 benthic algae metrics and 65 macroinvertebrate metrics and fish communities. Coefficients of variation (CVs) were calculated for the habitat measurements, metrics of benthic algae, and macroinvertebrate data as measures of variability. Annual variability of habitat data was generally greater at the mountain site than at the basin sites. The mountain site had higher CVs for water temperature, depth, velocity, canopy angle, streambed substrate, and most water-quality variables. In general, CVs of most benthic algae metrics calculated from the richest-targeted habitat (RTH) samples were greater at the mountain site. In contrast, CVs of most benthic algae metrics calculated from depositional-targeted habitat (DTH) samples were lower at the mountain site. In general, CVs of macroinvertebrate metrics calculated from qualitative multihabitat (QMH) samples were lower at the mountain site. In contrast, CVs of many metrics calculated from RTH samples were greater at the mountain site than at one of the basin sites. Fish communities were more variable at the basin sites because more species were present at these sites. Annual variability of benthic algae metrics was related to annual variability in habitat variables. The CVs of benthic algae metrics related to the most CVs of habitat variables included QMH taxon richness, the RTH percentage richness, RTH abundance of tolerant taxa, RTH percentage richness of halophilic diatoms, RTH percentage abundance of sestonic diatoms, DTH percentage richness of nitrogen heterotrophic diatoms, and DTH pollution tolerance index. The CVs of macroinvertebrate metrics related to the most CVs of habitat variables included the RTH trichoptera, RTH EPT, RTH scraper richness, RTH nonchironomid dipteran abundance (in percent), and RTH EPA (U.S. Environmental Protection Agency) tolerance, which is based on abundance. Many of the CVs of habitat variables related to CVs of macroinvertebrate metrics were the same habitat variables that were related to the CVs of benthic algae metrics. On the basis of these results, annual variability may have a role in the relationship of benthic algae and macroinvertebrates assemblages with habitat and water quality in the Santa Ana Basin. This report provides valuable baseline data on the variability of biological communities in the Santa Ana Basin. Variability in Lotic Communities in Three Contrasting Stream Environments in the Santa Ana River Basin, California, 1999–2001 By Carmen A. Burton 2 Variability in Lotic Communities, Three Contrasting Stream Environments, Santa Ana River Basin, Calif., 1999–200

The effect of shrubland and grassland vegetation types on soil fauna and flora activities in a mountainous semi-arid landscape of Iran

Airborne particulate matter, suspected to induce adverse effects on human health, have been one of the most important concerns regarding recent air pollution issues in Japan. To characterize regional and seasonal variations in emission sources of fine airborne particulate matter (d < 2 microm), monthly samples (n = 36 for each site) were collected at urban (Tokyo), suburban (Maebashi), and mountainous (Akagi) sites in Japan from April 2003 to March 2006. Multielement analysis of chemical species (Na, Al, K, Ca, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Sb, and Pb) was performed by inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry. The combined source receptor model, which consists of positive matrix factorization and chemical mass balance, determined the contributions of nine emission sources (local and continental soils, road dust, coal and oil combustion, waste incineration, steel industry, brake wear, and diesel exhaust) to the observed elemental concentrations. Large regional differences were identified in the source contributions among the observational sites. Diesel exhaust was identified as the most significant source (70% of identified contributions) at the urban site. Local and continental soils, coal combustion, and diesel exhaust were intricately assigned (20-30% each) to the suburban site. Continental soil was the predominant source (65%) at the mountainous site. Respective significant source contributions dominated the seasonal variations of total elemental concentrations at each site. These results suggest that a better understanding of the regional and seasonal characteristics of impacting emission sources will be important for improving regional environments.

Abstract. Results of continuous nitrogen oxide (NO), nitrogen dioxide (NO2), peroxyacetyl nitrate (PAN) and total reactive nitrogen (NOy) measurements along with seasonal field campaigns of nitric acid (HNO3) and particulate nitrate (NO3-) measurements are presented for a two-year period at the high-alpine research station Jungfraujoch (JFJ), 3580 m asl. The NOy mixing ratio and partitioning is shown to strongly depend on meteorological conditions. Knowledge of these meteorological transport processes allows discrimination between undisturbed (i.e. clean) and disturbed (i.e. influenced by regional pollution sources) free tropospheric (FT) conditions at the JFJ. Median NOy concentrations during undisturbed FT periods ranged from 350 pptv (winter, December to February) to 581 pptv (spring, March to May). PAN was found to be the dominant NOy species during spring and summer, whereas NO2 was most abundant during autumn and winter. Particulate nitrate was found to contribute significantly to total NOy during thermally induced vertical transport. Föhn events, synoptical lifting (e.g. fronts) and thermally induced vertical transport resulted in mixing ratios up to 10 times higher at the JFJ compared to undisturbed FT conditions. Furthermore this meteorological variability of the NOy concentration and partitioning often dominated the seasonal variability. As a consequence the use of filters at the JFJ (and other mountainous sites) is crucial for the interpretation of data from such measurement sites. This study presents a further development of meteorological filters for the high-alpine site Jungfraujoch, which also could be modified and adapted to other mountainous measurement sites.