Intensive Field Observations Research Articles

Station Area Planning and Resilient Urban Transformation: Insights from Siliguri Through Stakeholders’ Perspectives

The present research seeks to outline a common ground between the notions of urban aesthetics and inclusive planning by taking Siliguri Town station and its adjacent market as the cases. This article attempts to redirect the study of urban geography of Siliguri city away from macro-level analysis of space, which sometimes generates crude generalized discussions about the spatial development of urban landscapes, on the side of a more vigorous contemplation and critical consideration on the scope of micro-level planning alternatives for the city. Toward this objective, the research methodology is grounded on the analysis of historical databases, intensive field observation, and qualitative interviews. Through ten in-depth semi-structured interviews with key stakeholders including local body representatives, railway officials, planners, investors, as well as civil society organizations in Siliguri City, this study seeks to emphasize the factors that stakeholders in the city consider to be essential for the micro-scale development of Siliguri Town station neighborhood and its long-term effects on a number of actors. Findings from the interviews indicate that Siliguri Town station and its neighboring markets, such as Mahabirsthan and Hawkers’ Corner, are continuously growing as the places of urban contestation and struggle. To critically address these contestations, the research argues for the resurgence of Siliguri Town station neighborhood as the key urban territorial form for collaboration among central, state, and local government authorities as well as private players. The principal outcomes of this research, therefore, are expected to provide some micro-level planning alternatives, which can pave the path for an inclusive and planned production of urban space around Siliguri Town railway station, representing the heart of Siliguri city.

Analyzing The Culinary Potential In The Bandung Region, West Java

This article presents a comprehensive analysis of the culinary potential in the areas surrounding West Java, with a specific focus on Dipatiukur Streetfood in the city of Bandung. The main objective of this research is to identify and evaluate the competitive advantages and development opportunities of local culinary offerings in the region in-depth. The research method used is a combination of literature studies, intensive field observations, and in-depth interviews with various stakeholders, including business owners and the local community. The research findings indicate that Dipatiukur Streetfood has great potential to be developed as a unique culinary attraction. The identified advantages include the uniqueness of the menu, the quality of the fresh and high-quality raw materials, as well as the strong local wisdom embedded in the food processing and presentation processes. In addition, the traditional atmosphere and ambiance created in Dipatiukur Streetfood also becomes a particular draw for visitors who want to experience the typical Sundanese culinary experience. However, the study also revealed several challenges that need to be addressed in the development of Dipatiukur Streetfood, such as limited infrastructure and sanitation, lack of effective promotion and branding, as well as traditional business management. In addition, the regeneration and involvement of the younger generation has also become an important issue to preserve the local culinary heritage in the future. Based on the analysis, this article presents comprehensive development strategies to address these challenges. These strategies include improving infrastructure and sanitation, implementing effective promotion and branding programs, enhancing business management capabilities, as well as engaging the younger generation and cultural transformation. By implementing these strategies, it is expected that Dipatiukur Streetfood can be further developed as a competitive local culinary destination, which in turn can have a positive impact on the economy and cultural preservation of the local community.

Photochemical pollution during summertime in a coastal city of Southeast China: Ozone formation and influencing factors

Surface ozone (O3) has a significant impact on the air quality, and its concentrations have been increasing despite a distinct decrease in fine particulate matter (PM2.5) since 2013 in China. However, the formation mechanisms of photochemical O3 pollution in coastal regions are not fully understood. Therefore, an intensive field observation was conducted from July 8th to August 4th 2022 in Xiamen of Southeast China, combining with the observation-based model to reveal the formation and influencing factors of photochemical O3 pollution affected by the Western Pacific Subtropical High (WPSH). Results indicate that O3 pollution episodes were characterized by higher air temperature, lower relative humidity, lower wind speed, and higher concentrations of precursors (including volatile organic compounds (VOCs), NOx, and CO) compared with non-pollution episodes (p < 0.05). Stronger atmospheric oxidation capacity (AOC), OH reactivity, and ROx production rates during the O3 pollution episodes led to the remarkable increases in O3. Additionally, the photolysis of HCHO and other carbonyl compounds (48.6%), as well as O3 photolysis (41.3%) contributed the largest to ROx radical production, promoting the rapid formation of O3 during the pollution episodes. Reducing VOC concentrations not only decreased the net O3 production rates and AOC, but also weakened ROx self-reactions (Self-Rxns). Notably, Self-Rxns were weakened when the reduction percentage of NOx was from 10% to 20%, but decreasing NOx concentrations intensified Self-Rxns in other reduction percentages of NOx. This study provides a better understanding of photochemical O3 pollution mechanisms under the synoptic situation controlled by the WPSH, as well as the urgency of VOC reductions in the rapid development of coastal regions.

Causes Investigation of PM2.5 and O3 Complex Pollution in a Typical Coastal City in the Bohai Bay Region of China in Autumn: Based on One-Month Continuous Intensive Observation and Model Simulation

In order to investigate the causes of complex air pollution in coastal cities in the Bohai Rim of China, a one-month intensive field observation combined with model simulation was carried out in a typical city named Dongying in September 2022. The results showed that two PM2.5 and O3 complex pollution episodes occurred in Dongying in the observation period, with the primary pollutant being O3. Atmospheric photochemical reactions occurring under unfavorable meteorological conditions led to the production of O3 while at the same time facilitating the generation of nitrate, sulfate, and other secondary components of PM2.5 by enhancing the atmospheric oxidizing capacity, which promoted the formation of complex air pollution. It was worth noting that in the context of high pollutants emission, the occurrence of complex air pollution was more sensitive to the variation in meteorological conditions than to the change in pollutants emission. To continuously improve air quality and protect human health in Dongying, it is recommended that an effective regional joint air pollution prevention and control mechanism with neighboring cities should be established in the premise of effective local pollutants reduction, and special attention should be paid to the adverse effect of the air mass transportation from Bohai Bay.

Turbulence and fine sediment dynamics in a benthic boundary layer in Fujian Coastal Sea, SE China

A short-term (∼ 25 h) intensive field observation focused on flow, turbulence, suspended sediment concentration, and floc/particle size distributions was conducted in a coastal benthic boundary layer to understand flocculation and erosion/deposition processes of fine sediment. Observations showed suspended particles were mainly flocculated into the size range of microflocs (50-200 μm). Macroflocs (> 230 μm) occurred at slack tides and SPM (suspended particulate matter) concentrations decreased as they settled faster. Twofold intra-tidal variations in floc size and settling velocity were observed with a larger medium floc size of 140 μm and a settling velocity of 1.3 mm/s occurring at slack tides than peak flood/ebb tides with their corresponding values of 70 μm and 0.7 mm/s. This variability can be ascribed to the turbulence modulation in that low turbulence enhances aggregation to form large flocs but they turn to break down by high turbulence. The inverse relationship was found between floc size and turbulence shear rate, SPM concentration, and their product. SPM concentration covaried with bed stress and the low critical erosion stress (∼ 0.02 Pa) indicates that the cohesive bed was primarily eroded as aggregates which formed a fluff layer above the consolidated bed. The fine sediment dynamics behave as a loop from resuspension, through to breakup and re-aggregation, and to settling in response to intro-tidal turbulence variability. This looped behavior is vital for understanding the sequestration of organic carbon and pollutants in fine sediments, awaiting more detailed and longer-term field observations and the assemblage into numerical models.

The impact of emission reduction policies on the results of PM2.5 emission sources during the 2016 G20 summit: Insights from carbon and nitrogen isotopic signatures

Intensive field observations were conducted on the PM2.5, gaseous pollutants, δ13C, and δ15N values to evaluate the efficacy of much stricter air quality measures and emergency response strategies implemented in Hangzhou and Ningbo during the 2016 G20 Summit. Our data showed that δ13C values of PM2.5 samples collected in two cities varied from −30.8‰ to −24.2‰, with an average of −25.8‰ ± 1.1‰ during sampling periods. Similar δ13C values observed in the two cities indicated that there is no pronounced differences of carbon sources between the Hangzhou and Ningbo. Based on the Bayesian model, results indicated that C3 plant combustion contributed 47.8% and 47.2% to carbon sources of PM2.5 in Hangzhou and Ningbo, respectively. δ15N values of PM2.5 ranged from 2.0‰ to 13.7‰, with a mean value of 8.5‰ ± 2.5‰ during the whole campaign. Notably, more effective results were observed in reducing NH3 compared to NOx in Hangzhou and Ningbo. Additionally, a more reliable source apportionment approach using isotope fractionation effects and a Bayesian model was applied (improved Bayesian model), which reduced the uncertainty in the apportionment of nitrogen sources. The estimated fractionation effects from NH3 to NH4+ averaged at 16.19‰ ± 3.49‰, and from NOx to NO3− averaged at 12.94‰ ± 2.60‰, respectively. Compared to the results of the Bayesian model, the contributions of NOx from coal combustion (13.8%) and vehicle exhausts (11.6%), and NH3 from coal combustion (12.1%) and vehicle exhausts (12.5%) by improved Bayesian model were more consistent with the emission inventory. Collective evidence of multiple isotopes indicated that pollution emissions were sensitive in response to strict control measures. Our results also revealed that fossil fuel combustion reduction and regional control policies should be synergistically implemented for better air quality.

Spatial reconstruction of long-term (2003–2020) sea surface pCO2 in the South China Sea using a machine-learning-based regression method aided by empirical orthogonal function analysis

Abstract. The South China Sea (SCS) is the largest marginal sea of the North Pacific Ocean, where intensive field observations, including mappings of the sea surface partial pressure of CO2 (pCO2), have been conducted over the last 2 decades. It is one of the most studied marginal seas in terms of carbon cycling and could thus be a model system for marginal sea carbon research. However, the cruise-based sea surface pCO2 datasets are still temporally and spatially sparse. Using a machine-learning-based method facilitated by empirical orthogonal function (EOF) analysis, this study provides a reconstructed dataset of the monthly sea surface pCO2 in the SCS with a reasonably high spatial resolution (0.05∘ × 0.05∘) and temporal coverage between 2003 and 2020. The data input to our model includes remote-sensing-derived sea surface salinity, sea surface temperature, and chlorophyll, the spatial pattern of pCO2 constrained by EOF, atmospheric pCO2, and time labels (month). We validated our reconstruction with three independent testing datasets that are not involved in the model training. Among them, Test 1 includes 10 % of our in situ data, Test 2 contains four independent in situ datasets corresponding to the four seasons, and Test 3 is an in situ monthly dataset available from 2003–2019 at the South East Asia Time-series Study (SEATs) station located in the northern basin of the SCS. Our Test 1 validation demonstrated that the reconstructed pCO2 field successfully simulated the spatial and temporal patterns of sea surface pCO2 observations. The root mean square error (RMSE) between our reconstructed data and in situ data in Test 1 averaged ∼10 µatm, which is much smaller (by ∼50 %) than that between the remote-sensing-derived data and in situ data. Test 2 verified the accuracy of our retrieval algorithm in months lacking observations, showing a relatively small bias (RMSE of ∼8 µatm). Test 3 evaluated the accuracy of the reconstructed long-term trend, showing that, at the SEATs station, the difference between the reconstructed pCO2 and in situ data ranged from −10 to 4 µatm (−2.5 % to 1 %). In addition to the typical machine learning performance metrics, we assessed the uncertainty resulting from reconstruction bias and its feature sensitivity. These validations and uncertainty analyses strongly suggest that our reconstruction effectively captures the main spatial and temporal features of sea surface pCO2 distributions in the SCS. Using the reconstructed dataset, we show the long-term trends of sea surface pCO2 in five subregions of the SCS with differing physicobiogeochemical characteristics. We show that mesoscale processes such as the Pearl River plume and China coastal currents significantly impact sea surface pCO2 in the SCS during different seasons. While the SCS is overall a weak source of atmospheric CO2, the northern SCS acts as a sink, showing a trend of increasing strength over the past 2 decades. The data used in this article are available at https://doi.org/10.57760/sciencedb.02050 (Wang and Dai, 2022).

Small-Scale Marijuana Growing: Deviant Careers as Serious Leisure

Previous research on marijuana growers in the United States has primarily focused on those who have been incarcerated for the activity (Weisheit, 1990; 1998). These growers tend to produce large amounts of the product. It may be that large scale marijuana growers who have been arrested may differ in their reasons for growing, their style of growing and distributing and in how they view marijuana growing as an activity from different types of growers; namely small-scale, indoor hydroponic growers who grow primarily for personal use and enjoyment. Our study analyzes one social network of marijuana growers in central and northern Florida. Through intensive field observations and qualitative interviews with 8 people involved in this closed social network of marijuana growers, we discovered that the growers all followed a similar pattern of initial trial and error, learning new techniques from one another to improve their product, to finally maintaining techniques that enabled them to maximize taste, potency and yield. All of the growers in our sample were white middle class men (6) and women (2) with at least a college degree who had already or planned to enter white collar occupations (e.g., a teacher or business owner). Although profitable, the growers greatly downplayed the importance of making money as a reason for growing, describing the endeavor as a passionate activity they performed for enjoyment, to save their own money, and for the high regard they have of plants in general. Discontinuing the activity (thus exiting the deviant career) is often influenced by such contingencies as risk of detection, commitment to family, and conventional occupations. Future research is needed to compare and contrast different kinds of marijuana growers including those whose growing activities are legitimated by state law.

Prey composition and correlation between morphometry and prey biomass weight of the endemic Nepenthes bicalcarata in Kalimantan, Indonesia

Abstract. Setiawan H, Hakim L, Fernandes AAR, Retnaningdyah C. 2022. Prey composition and correlation between morphometry and prey biomass weight of the endemic Nepenthes bicalcarata in Kalimantan, Indonesia. Biodiversitas 23: 5453-5460. Nepenthes bicalcarata Hook.f. is an endemic plant of the north-western part of Borneo, which is threatened by the conversion of its habitat. The understanding of the ecology of N. bicalcarata in regard to its prey is limited. This research aims to analyze the prey composition of N. bicalcarata and to investigate the correlation between pitcher morphometry and prey biomass weight. This research was done from November 2021 to March 2022 in a peat swamp primary forest in Sintang District, West Kalimantan Province, Indonesia. We used a quantitative descriptive approach and exploration method to gather data from N. bicalcarata in-situ habitat. The morphometry data of N. bicalcarata pitchers were collected in the field while the biomass trapped in N. bicalcarata pitcher liquid was sampled with a plastic bag and preserved with 70% of alcohol. Seven upper pitchers and 39 lower pitchers were recorded in this research. The composition of N. bicalcarata preys was dominated by Formicidae family including C. schmitzi, Polyrhachis sp. and Crematogaster sp.. Besides that, there were also mosquito larvae, ladybugs larvae, Ceratopogonidae larvae and some unidentified flying arthropods as the prey of N. bicalcarata. We found the plant’s parts in the lower pitchers of N. bicalcarata in the peat swamp forest, suggesting a possible mechanism of this plant to extract plant’s parts as alternative nutrient sources, yet this needs further research and intensive field observation. The correlation between pitcher volume and prey biomass weight was significant with P-value =0.00 (&lt;0.01) and regression is formulated as Y (prey weight) = -0.1727 + 0.0039X (pitcher volume). This means that any increase in N. bicalcarata’s pitcher volume will increase the weight of the biomass linearly.

Prey composition and correlation between morphometry and prey biomass weight of the endemic Nepenthes bicalcarata in Kalimantan, Indonesia

Abstract. Setiawan H, Hakim L, Fernandes AAR, Retnaningdyah C. 2022. Prey composition and correlation between morphometry and prey biomass weight of the endemic Nepenthes bicalcarata in Kalimantan, Indonesia. Biodiversitas 23: 5453-5460. Nepenthes bicalcarata Hook.f. is an endemic plant of the north-western part of Borneo, which is threatened by the conversion of its habitat. The understanding of the ecology of N. bicalcarata in regard to its prey is limited. This research aims to analyze the prey composition of N. bicalcarata and to investigate the correlation between pitcher morphometry and prey biomass weight. This research was done from November 2021 to March 2022 in a peat swamp primary forest in Sintang District, West Kalimantan Province, Indonesia. We used a quantitative descriptive approach and exploration method to gather data from N. bicalcarata in-situ habitat. The morphometry data of N. bicalcarata pitchers were collected in the field while the biomass trapped in N. bicalcarata pitcher liquid was sampled with a plastic bag and preserved with 70% of alcohol. Seven upper pitchers and 39 lower pitchers were recorded in this research. The composition of N. bicalcarata preys was dominated by Formicidae family including C. schmitzi, Polyrhachis sp. and Crematogaster sp.. Besides that, there were also mosquito larvae, ladybugs larvae, Ceratopogonidae larvae and some unidentified flying arthropods as the prey of N. bicalcarata. We found the plant’s parts in the lower pitchers of N. bicalcarata in the peat swamp forest, suggesting a possible mechanism of this plant to extract plant’s parts as alternative nutrient sources, yet this needs further research and intensive field observation. The correlation between pitcher volume and prey biomass weight was significant with P-value =0.00 (&lt;0.01) and regression is formulated as Y (prey weight) = -0.1727 + 0.0039X (pitcher volume). This means that any increase in N. bicalcarata’s pitcher volume will increase the weight of the biomass linearly.

Intra-annual variation in microclimatic conditions in relation to vegetation type and structure in two tropical dry forests undergoing secondary succession

Microclimate acts as a strong filter on species performance in restored and regenerating forests, particularly in seasonally dry tropical forests (SDTF). Yet few studies have measured microclimate patterns across succession in SDTF. Furthermore, although dynamic vegetation models simulate microclimate, evaluation of these simulated variables with field observations has been relatively uncommon. Here, we investigated the seasonal patterns of soil temperature and soil water in naturally regenerated and planted successional vegetation in SDTF in Costa Rica and Puerto Rico, using complementary approaches of intensive field observations and simulation modeling with the Ecosystem Demography model. We found that plots representing later successional stages were wetter on average, but only during the dry season. During the wet season, mean soil water did not differ across vegetation types, but open, early successional vegetation experienced more frequent extreme wet and dry conditions than older forest and plantations. Soil temperature tended to decline with forest structure, and later successional vegetation also experienced less extreme daily temperature fluctuations. Basal area and leaf area index were the best predictors of differences in soil water and temperature across plots. Model simulations were consistent with observations of wet season soil temperature and soil water, but the model failed to reproduce dry season soil moisture dynamics, suggesting that further work is needed to reduce model biases in microclimate variables. Collectively, our results imply that common assumptions about how microclimates influence successional processes in SDTF should be revisited.

Economic Feasibility of Plastic Shelter Tomato Production Method under Rain-Fed in Fogera Plain, North Western Ethiopia

The research intervention was conducted in Fogera plain commonly known and consists of (Fogera, Dera and Libokemkem districts) of South Gondar Zone to evaluate economic feasibility of the new tomato production method using plastic shelter under rain fed production condition. Two types of improved tomato varieties were used known as Melkasalsa and melkashola, each variety within 200 m 2 plots of land. A sum of 5 kebeles/sites and 11 technology beneficiaries (farmers) were addressed under this intervention in three districts. Data on input costs, benefits among other parameters were collected and recorded through intensive field observation and follow up, field days, focused group discussion. Quantitative types of data such as yield, participants in different events through field day, training and exchange visit and qualitative types of data like feed backs, farmers’ perception and preference on demonstrated rice technologies. The use of plastic shelter in tomato production under rain-fed condition had considerable impact on yield performance. The relative yield advantage of tomato production using plastic shelter is better than without shelter production. Regarding profitability issues, the result shows, tomato production using plastic shelter was by far profitable than without shelter production in both varieties. The estimated value of marginal rate of return with shelter production was greater than one for both varieties. An investment of one Ethiopian Birr (ETB) on new production method using plastic shelter could generate additional net income of 20 ETB and 14 ETB from melkasalsa and melkashola varieties, respectively. Hence farmers and respective bodies need to strengthen production of tomato in the rainy season using shelter to get more returns and enhance their livelihood and economic benefits. Keywords: Marginal rate of return, Melka Salasa, Melka shola, Partial budget analysis, Plastic shelter, rain-fed DOI: 10.7176/JESD/13-1-02 Publication date: January 31 st 2022

Morphology, sedimentology and origin of an anomalous cut-off along the Pravara river, deccan trap region, India

River meanders have always been an intriguing subject in fluvial geomorphology because of their ubiquity, dynamism, remarkable forms and practical consequences of their movement. Sometimes a relatively straight channel flowing over bedrock may develop a lone meander bend cut-off which is very out of the place from the surrounding area. The occurrence of a sudden bend along a river may not be a meandering bend but may be manifestation of sudden change in the river dynamism due to many reasons, such as, lithology, change in rainfall regime, tectonics etc. The formation of such features highlights the behavior of river in the past. One such striking feature has been observed along the River Pravara in the Deccan Trap Region, Maharashtra, India. Rivers in Deccan Trap Region do not meander and form cut-offs by rule. It is rocky country where rivers flow in deeply incised bedrock. Hence, the observed feature displays a striking anomaly in this region. Hence, an attempt has been made in the present paper to evaluate the mode of formation of this single cut-off along this channel. Morphological and sedimentological data were generated and analyzed for the channel loop and the link channel to understand the competence of the river in the past and present which were directly or indirectly responsible for the development of this channel anomaly in this reach. Based on the results of the analysis and intensive field observations, it has been inferred that this is a classic example of natural morphological adjustment of a river when a set of events occurred, first retardation of vertical erosion encountering bedrock followed by series of floods to induce the channel to divert from the original path to resume the present course. Presence of a tributary further aided to the process of the loop development. The study can provide additional knowledge to the studies involving anomalous channel cut-offs at any part of the world.

Ovariectomy As a Management Technique for Suburban Deer Populations

ABSTRACTOverabundant suburban deer (Odocoileus spp.) are a source of human‐wildlife conflict in many communities throughout the United States. Deer‐vehicle collisions, impacts to local vegetation, tick‐borne pathogens, and other negative interactions are typical reasons cited for initiating deer management programs. Social attitudes, legal constraints, and perceived safety concerns lead many communities to examine nonlethal management options. Surgical sterilization is currently the only nonlethal method available to permanently sterilize females with a single treatment. However, there are limited data demonstrating methods and outcomes in management programs that sterilize a high percentage (&gt;90%) of local populations of females, particularly regarding the impact of immigration on non‐isolated populations. We present data from 6 surgical sterilization sites with geographically open populations in California, Maryland, Michigan, New York, Ohio, and Virginia, USA. From 2012 to 2020 we sterilized 493 deer, primarily via ovariectomy, and conducted annual or periodic population estimates using camera surveys, road‐based distance sampling, and intensive field observations to assess population trends. Study sites ranged from 1.2 km2 to 16.5 km2 with ~47–169 individuals, resulting in approximate densities of 6–63 deer/km2. For all sites we noted an average reduction of ~26% (17%–36%) from Year 1 to Year 2. Four years after initial treatment, we documented an average population reduction of ~45% (29%–56%). During the first year, the average cost per deer sterilized at locations where bait was used was US$1,185 ($927–$1,572). Surgical sterilization projects demonstrate that significant reductions in local deer densities using high‐percentage, surgical sterilization programs can be achieved in non‐insular locations, where baited deer are approachable by vehicle for darting. Sustained sterilization efforts may be necessary, as is the case with all deer management programs, in areas where immigration is possible, and all the animals are not sterilized. © 2021 The Wildlife Society.

Episodic nearshore-offshore exchanges of hypoxic waters along the north shore of Lake Erie

We investigate the nearshore-offshore exchange of hypoxic waters during episodic coastal upwelling events in the nearshore waters of northern Lake Erie using intensive field observations and a validated hydrodynamic and water quality model. We observe wind-induced coastal upwelling events to be the dominant nearshore physical process in the lake which are energized every 5–10 days. When the winds were predominantly blowing from the west or south-west, epilimnetic waters were transported to the offshore bringing in hypolimnetic waters with low temperature (8–10 °C), dissolved oxygen (DO: 0–6 mg L−1) and pH (6–7) to the nearshore zones. During these events, vertical diffusivity coefficients decreased from 10−2 m2 s−1 to values as low as ~ 10−7 m2 s−1. In late summer, the coastal upwelling events in the nearshore waters lower the near bottom DO to hypoxic levels (DO < 2 mg L−1). Lake-wide observations of DO and pH show that they are positively and linearly correlated while in the nearshore DO and pH experience spatial and temporal variability where upwelling events were developed, which were further assessed using a three-dimensional model. The model accuracy to reproduce offshore hypoxia was first assessed on a lake-wide basis using a coarse resolution model for a five-year period (2008–2012) and in nearshore waters using a higher resolution model for 2013. We use the model results to delineate the near bottom areas experiencing hypoxia at time scales longer than 48 h.

Size distribution and formation processes of aerosol water-soluble organic carbon during winter and summer in urban Beijing

Size-resolved aerosol organic carbon (OC) and water-soluble OC (WSOC) was determined weekly in urban Beijing between 2013 and 2018. The results showed that in winter, the concentrations of WSOC and OC in fine (<2.1 μm) and coarse (>2.1 μm) mode were highest in 2013. During the following years, the concentrations of WSOC and OC were lower but an increasing trend was found from 2014 to 2016, which might be due to the increasing precursor concentrations. From summer 2013 to 2018, the concentrations of OC and WSOC in both fine and coarse mode decreased, which might be affected by decreasing emission intensity and photochemical oxidation. To characterize the seasonality of WSOC, two intensive field observations were further performed in winter 2013 and summer 2018. In winter of 2013, WSOC was mainly enriched in PM1 (<1 μm) on clean days and lightly polluted days. In addition, the fine mode maximum shifted from 0.43-0.65 μm to 1.1–2.1 μm with the haze development due to the hygroscopic growth of particles. In summer of 2018, the WSOC was mainly concentrated in PM1, but in a few samples, the maximum size appeared in coarse mode. This difference might due to the different relative humidity and air mass sources. While the formation process of WSOC in winter was affected by photochemical oxidation below 2.1 μm, in 1.1–2.1 μm, it tended to change from photochemical oxidation to aqueous-phase oxidation. For the coarse mode WSOC formation in winter, however, it was mainly affected by heterogeneous processes. The findings advanced our understanding of the annual trends, size distribution and formation processes of WSOC, with significant implications for air pollution control in Beijing and surrounding regions.

Volatile organic compounds and ozone air pollution in an oil production region in northern China

Abstract. Oil and natural gas (O&amp;amp;NG) exploration presents a significant source of atmospheric volatile organic compounds (VOCs), which are central players of tropospheric chemistry and contribute to formations of ozone (O3) and secondary organic aerosols. The impacts of O&amp;amp;NG extraction on regional air quality have been investigated in recent years in North America, but have long been overlooked in China. To assess the impacts of O&amp;amp;NG exploration on tropospheric O3 and regional air quality in China, intensive field observations were conducted during February–March and June–July 2017 in the Yellow River delta, an oil extraction region in northern China. Very high concentrations of ambient VOCs were observed at a rural site, with the highest alkane mixing ratios reaching 2498 ppbv. High-O3 episodes were not encountered during wintertime but were frequently observed in summer. The emission profiles of VOCs from the oil fields were directly measured for the first time in China. The chemical budgets of ROx radicals and O3 were dissected with a detailed chemical box model constrained by in situ observations. The highly abundant VOCs facilitated strong atmospheric oxidation capacity and O3 formation in the region. Oxygenated VOCs (OVOCs) played an essential role in the ROx primary production, OH loss, and radical recycling. Photolysis of OVOCs, O3, and HONO as well as ozonolysis reactions of unsaturated VOCs were major primary sources of ROx. NOx was the limiting factor of radical recycling and O3 formation. This study underlines the important impacts of O&amp;amp;NG extraction on atmospheric chemistry and regional air quality in China.

Characterization and formation of the pristine rhizoliths around Artemisia roots in dune soils of Tengeri Desert, NW China

Rhizoliths are the products of mineralization, petrification, or fossilization around and/or within plant roots. Among them, carbonate rhizoliths are the most common. Pristine carbonate rhizoliths with co-existing plant root relicts in the Tengeri Desert, NW China were studied, with a combination of intensive field observations and laboratory methods such as microscopy, scanning electronic microscopy, energy dispersive X-ray spectra, radiocarbon dating, and isotope mass spectrometer. The field observations revealed that the pristine rhizoliths are only present at the sites where Artemisia sphaerocephala Krasch are growing i.e. in swales among sand dunes. Soil moisture of the swales is the main controlling factor of rhizoliths formation. It is in turn affected by the soil physical properties, landscape position, and climate variability, consistent with the locations of sampled rhizoliths in the swales where Artemisia plants are mostly distributed. The 14C AMS dating indicated that the rhizoliths are much older (4000–5000 years) than their co-existing modern plant root relicts in agreement with field observations. Morphological, mineralogical and isotopic analyses revealed that carbon sources used for the rhizoliths formation were partially derived from decomposing plant roots but with significant contribution from dissolution of lithogenic carbonates. The calcium sources were suggested to be the in situ weathering of minerals (mostly lithogenic carbonates) and the pressure-dissolution of carbonates. Enough CO2 from the root decomposition have triggered carbonate accumulation around the root to form rhizoliths. Other minor chemical components of the root are S, N, P, which produce acidic water with the negative ions of SO42−, NO3–, PO43-, have also favored acidic soil environment and enhanced carbonate dissolution and mineral weathering. Redox environment around Artemisia roots were also observed to be a key factor for the pristine rhizolith formation. The pristine rhizoliths were preferentially formed in semi-closed redox condition with water nearly always available at intermediate depths. In addition, they were formed through carbonate epidiagenesis in shallow soils of the desert. Altogether, our results showed that the formation of the pristine rhizoliths was affected by the combination of several environmental factors. This led us to propose a conceptual model of rhizolith formation in desert soils.

THE DIURNAL BIRDS OF PREY (RAPTORS) IN THE MESOPOTAMIAN MARSHES OF SOUTHERN IRAQ WITH NOTES ON THEIR CONSERVATION STATUS

Birds of prey (Raptors) are top predator avian species that many migrate annually through Mesopotamian marshes in southern Iraq toward their wintering grounds in Arabia and Africa, while others are breeding residents; however, information on their current status is scarce. From January 2016 to April 2019, a total of 20 field expeditions were conducted in the geographical zone of the Mesopotamian marshes, wetlands of international importance. The survey covered the Central Marshes, Al-Hammar and Hawizeh Marsh. One of the objectives of the field surveys is to list the raptors species that wintering and/or migrating through the Mesopotamian marshes and to understand their current spatial and temporal distribution. In the present study, a total of 32 species of diurnal raptors are recorded through intensive field observations, reviewing literature records, and personal communications of unpublished data. Moreover, eight species listed by the International Union for Conservation of Nature IUCN Red List are recorded which highlight the ecological importance of the Mesopotamian marshes as a major stopover site for globally threatened raptors. Besides species persecution, observed threats such as habitat destruction, climate change, and pollution were severely influencing birds of prey communities in the Mesopotamian marshes which warrant further conservation actions.

Bureaucratic recentralisation of Nepal's community forestry sector

This paper explores the forest bureaucracy's practices of implementing community forest policies in Nepal and how this shapes the realities of community forestry for forest user groups. To this end, we conducted a content analysis of community forest management plans; surveyed 74 community forest user groups; conducted intensive field observation in six community forests and interacted with executive committee members and forest bureaucrats from two western hill districts. Our results show that forest user groups were hardly aware of their formal rights, including the obligations of forest bureaucrats to deliver free-of-charge services and technical support. Nobody holds forest bureaucrats accountable for failing to fulfil this part of their official duties. Rather, the forest bureaucrats have established different legal and extralegal processes and mechanisms through which they regain and maintain control over community forest resources. We call this 'bureaucratic recentralisation', and it allows forest bureaucrats to reap personal benefits, including unofficial revenues for delivering statutorily no-cost services.