Microclimatic Effects Research Articles

Foraging behavior and work patterns of Bombus terrestris (Hymenoptera: Apidae) in response to tomato greenhouse microclimate

Abstract Bumblebees play a significant role as pollinators for many wild plants and cultivated crops, owing to their elongated proboscis, resilience to diverse weather conditions, robustly furred bodies, and their unique capacity for buzz-pollination. To better understand the effect of greenhouse microclimates on bumblebee foraging behavior and working modes, a long-term record of foraging activity for each Bombus terrestris L. (Hymenoptera: Apidae) forager was monitored by the Radio-frequency identification system. The pattern of task performance, including constant housing, foraging, and day-off rotation, was examined under the microclimate. In addition, the correlation between foraging activity of bumblebees and temperature, relative humidity, illumination in the greenhouse, and pollen viability of tomato plants was further analyzed. Our findings revealed that B. terrestris can respond to microclimatic factors and plant resources while also exhibiting a suitable working pattern within the colony. Day-off rotation was observed as a strategy employed by foragers to prolong their survival time. This division of labor and task rotation may serve as strategies for the survival and development of the colony. Our research may contribute to fully understanding how microclimate and plants influence pollinator behavior within greenhouses, thereby optimizing the pollination management of bumblebees on greenhouse crops.

Functional groups of leaf phenology are key to build climate-resilience in cocoa agroforestry systems

Agroforestry has the potential to enhance climate change adaptation. While benefits from agroforestry systems consisting of cash crops and shade trees are usually attributed to the (shade) trees, the trees can also have negative impacts due to resource competition with crops. Our hypothesis is that leaf phenology and height of shade trees determine their seasonal effect on crops. We test this hypothesis by categorizing shade tree species into functional groups based on leaf phenology, shade tree canopy height and shade tree light (wet and dry season) interception as well as the effects. To this end, leaf phenology and the effects on microclimate (temperature, air humidity, intercepted photoactive radiation (PAR)), soil water, stomatal conductance and cocoa yield were monitored monthly during wet and dry seasons over a two-year period on smallholder cocoa plantations in the northern cocoa belt of Ghana. Seven leaf phenological groups were identified. In the wet season, highest buffering effect of microclimate was recorded under the trees brevi-deciduous before dry season. During dry season, high PAR and lowest reduction in soil moisture were observed under the trees in the group of completely deciduous during dry season. The evergreen groups also showed less reduction in soil water than the brevi-deciduous groups. In the wet season, shade tree effects on cocoa tree yields in their sub canopy compared to the respective control of outer canopy with full sun ranged from positive (+10 %) to negative (-15 %) for the deciduous groups, while yield reductions for the evergreen groups ranged from −20 % to −33 %. While there were negative yield impacts for all phenological groups in the dry season, the trees in completely deciduous during dry season group recorded least penalties (-12 %) and the trees with evergreen upper canopy the highest (-35 %). The function of shade trees in enhancing climate resilience is therefore strongly dependent on their leaf phenological characteristics. Our study demonstrates how the key trait leaf phenology can be applied to successful design of climate-resilient agroforestry systems.

An assessment of the seasonally dependent biophysical mechanism and dynamic land use change: A Research Effort from Emerging Urban Agglomeration of West Bengal

The behavior of the biophysical components needs to be closely observed while taking seasonal perspectives into account. This study focuses on seasonal analysis of biophysical components and dynamics of land use changes. This study examines the spatiotemporal seasonal variation among land surface temperature (LST), NDVI, and NDWI, with a focus on the two main sub-tropical climatic seasons summer and winter. We use correlation and regression analysis to assess the season-wise relationship between LST and biophysical indices with the help of grouped marginal plots. The comparison analyses of the biophysical components and land use change for a longer period from 1991-2021 with their matrix was undertaken in five urban agglomerations (UA) like Asansol, Siliguri, Kolkata, English Bazar and Kharagpur. The maximum likelihood classification technique was used to categorize multi-temporal Landsat images for each of the five growing UA in West Bengal. The most intriguing finding is that in all UAs, from 1991 to 2021, built-up area increased to become the predominant land. Thus, the vegetation and agricultural land are in danger in every location of West Bengal, whether it is plain or hilly, because of the land's gradual conversion to concrete or built-up areas over time. Additionally, the result shows that in summer and winter seasons, LST was observed growth due to the rapid urban built-up area expansion. It is also found that LST and NDVI have a close negative relationship, but LST and NDWI do not have any perfect relationship. Therefore, to lessen the warming effect of urban microclimates, policymakers should be concerned about future urban expansion that is both horizontal and vertical. An appropriate strategy for environmentally friendly construction, green buildings, and cool roof technologies should be developed.

Drought field experiments: how to adapt rainout shelters to agroforestry?

AbstractAgroforestry could be a major strategy to adapt agriculture to climate change, thanks to the microclimate effects of trees and improved infiltration. However, the experimental validation of these claims is scarce. In this methodological review, we discuss options for the experimental simulation of drought conditions in agroforestry field experiments, comparing it with strategies adopted in natural, agricultural, or forestry ecosystems. We classify rainout shelters used in field experiments according to mobility, completeness of rain interception and height of rainout shelter. We show that specificities of agroforestry systems create constraints and require compromises in the design and operation of rainout shelters. We conclude that large rainout shelters, which induce drought for both the trees and the crops while limiting artifacts and biases, would be most relevant for studying the resistance of agroforestry systems to drought. Unfortunately, the review of rainout shelters already used in agroforestry systems reveals a lack of rainout shelters capable of intercepting rain on both trees and crops, achieving total rain interception, while being relatively low-cost and manageable by a small team. Therefore, we benchmark three novel rainout shelter designs that we tested in a mature agroforestry system under Mediterranean climatic conditions. We discuss their advantages and disadvantages in terms of both scientific and operational aspects. While compromises had to be done between experimental design, risks of artifact/bias, effectiveness, ease of installation, operation and maintenance, and agricultural management, these prototypes are starting points for achieving well-performing rainout shelters and testing the effects of drought in agroforestry experiments.

The affinity of vascular plants and bryophytes to forest microclimate buffering

Abstract With recent advances in technology and modelling, ecologists are increasingly advised to use microclimate, not the usual coarse scale macroclimate based on weather stations, to better reflect the proximal conditions that species experience. This is especially relevant in forest ecosystems, where natural disturbances and management create substantial heterogeneity in microclimates. Under dense canopies, species may experience buffered (less extreme) microclimate temperatures relative to macroclimate, as well as increased relative humidity, reduced light and wind. Focusing on understorey plants, we investigated species response curves to the buffering capacity of the canopy layer, measured as the log‐transformed slope parameter of the microclimate to macroclimate linear relationship. If lower or higher than zero, microclimate temperatures are buffered or amplified, respectively, relative to macroclimate. During leaf‐on conditions (July–September 2021), we measured hourly microclimate temperatures in 157 plots across three temperate deciduous forests with contrasted macroclimates. We used paired hourly macroclimate measurements from nearby weather stations to derive the slope parameter, quantifying microclimate buffering. We surveyed vascular plant and bryophyte communities in 400 m2 plots centred on our microclimate sensors. Species were classified into three groups of forest affinity: core specialists; edge specialists; and generalists. We fitted generalized linear mixed‐effects models, by forest affinity group and by species, to obtain logistic response curves of the probability of occurrence against microclimate buffering. The species' optimum was computed as the microclimate effect that maximizes the species' probability of presence. We found contrasted microclimate preferences: Most bryophytes as well as the vascular plants classified as forest core specialists had an optimum in microclimate buffering, while forest edge specialists and generalists among vascular plants had an optimum in microclimate amplification. As canopies undergo increased disturbance frequency and intensity, more generalists and less forest core specialists might thus be expected in understorey communities, especially for bryophytes. Synthesis. Understorey plants have a species‐specific affinity to the forest microclimate, which we quantify for the first time. The investigation of species response curves to microclimate processes—buffering or amplification—can improve our understanding of the ecology of understorey plants, and help us anticipate their redistribution under climate change.

The microclimatic effects of the native shrub Ephedra californica (Mormon tea) in California drylands.

The impacts of climate change can be profound in many ecosystems worldwide, including drylands such as arid and semi-arid scrublands and grasslands. Foundation plants such as shrubs can provide microclimatic refuges for a variety of taxa. These shrubs can directly influence micro6 environmental measures, and indirectly increase the local environmental heterogeneity as a result. We examined the hypothesis that, in comparison to an open gap, foundation shrubs improve the microclimate beneath their canopy and that microclimate is in turn a significant predictor of annual vegetation. The following predictions were made: 1) mean air temperature (NSAT), ground temperature (SGT), and vapour pressure deficit (VPD) will be significantly lower under the shrubs than in the open microsites; 2) shrub canopy size predicts microclimate; 3) site-level aridity estimates and percent shrub cover influence annual plant abundance and richness; and 4) the site13 level mean of NSAT and VPD predict annual plant abundance and richness. Our study took place in Southwestern California, U.S.A. We used a handheld device with a probe to measure microclimatic variables such as near-surface air temperature (NSAT), near-surface relative humidity (NSRH), and surface ground temperature (SGT) at the shrub species Ephedra californica and in the open gap, across six sites in California, United States. Air temperature and RH were then used to calculate VPD. The mean number of vascular plant species across each site was also recorded. Only SGT was significantly reduced under shrub canopies. Canopy volume was not a significant predictor of all three microclimatic variables, demonstrating that even small, low-stature shrubs can have facilitative effects. Furthermore, total shrub cover and aridity at sites significantly predicted mean plant richness and abundance. There were significantly more plants associated with shrubs and there were significantly more species associated with the open. Mean air temperature and VPD at the site-level significantly predicted vegetation abundance and richness, though microsite-level differences were only significant for richness. Foundation shrubs are a focal point of resiliency in dryland ecosystems. Understanding their impact on microclimate can inform us of better management, conservation, and restoration frameworks.

Microclimate monitoring in commercial tomato (Solanum Lycopersicum L.) greenhouse production and its effect on plant growth, yield and fruit quality

IntroductionHigh annual tomato yields are achieved using high-tech greenhouse production systems. Large greenhouses typically rely only on one central weather station per compartment to steer their internal climate, ignoring possible microclimate conditions within the greenhouse itself.MethodsIn this study, we analysed spatial variation in temperature and vapour pressure deficit in a commercial tomato greenhouse setting for three consecutive years. Multiple sensors were placed within the crop canopy, which revealed microclimate gradients.Results and discussionDifferent microclimates were present throughout the year, with seasonal (spring – summer – autumn) and diurnal (day – night) variations in temperature (up to 3 °C, daily average) and vapour pressure deficit (up to 0.6 kPa, daily average). The microclimate effects influenced in part the variation in plant and fruit growth rate and fruit yield – maximum recorded difference between two locations with different microclimates was 0.4 cm d-1 for stem growth rate, 0.6 g d-1 for fruit growth rate, 80 g for truss mass at harvest. The local microclimate effect on plant growth was always larger than the bulk climate variation measured by a central sensor, as commonly done in commercial greenhouses. Quality attributes of harvested tomato fruit did not show a significant difference between different microclimate conditions. In conclusion, we showed that even small, naturally occurring, differences in local environment conditions within a greenhouse may influence the rate of plant and fruit growth. These findings could encourage the sector to deploy larger sensor networks for optimal greenhouse climate control. A sensor grid covering the whole area of the greenhouse is a necessity for climate control strategies to mitigate suboptimal conditions.

Evaluation of the urban heat island effect based on 3D modeling and planning indicators for urban planning proposals

ABSTRACT Urban planning plays an important role in the formation of urban space and microclimate. As a middle-level planning in the Chinese urban planning system, regulatory planning has a direct impact on the shaping of 3D urban space and can maximize the operability of urban planning. However, 3D space formation is not considered in the present preparation of regulatory plans, which leads to a misunderstanding of possibly formed 3D landscapes and microclimatic effects after the plan implementation. To support 3D visualization and quantitative analysis of the urban heat island effect (UHI) for regulatory planning, this study proposes a rule-based 3D modeling method to efficiently generate 3D models. The main elements of 3D models (terrain, building, road, vegetation, and land parcel) and their content were determined after analyzing the characteristics of 3D models in the regulatory plan. The 3D modeling process was constructed and combined with an UHI evaluation model through CGA programming. An index called heat island potential (HIP) was used as the UHI evaluation index and can be quantified using the correlation equations between planning indicators and HIP. The proposed method can support the planners to generate 3D models for a planning proposal, and simultaneously analyze 3D spatial effect and UHI.

Microclimatic effects of tree shelters on the early establishment and resilience of seeded acorns vs. outplanted seedlings

Little is known about the effects of tree shelters on the early response of oak seedlings produced by acorn seeding. In this paper, we explore the effects on holm oak (Quercus ilex L. subsp. ballota (Desf.) Samp.) seedlings of the microenvironment created by the tree shelters and the restoration method (seeding vs. outplanting) in terms of emergence, survival, growth, and resilience after harvesting. For this purpose, seedling height [H], root collar diameter [RCD], number of leaves, and aerial biomass were monitored. We made two sowings of acorns in February 2017 and February 2018, together with a seedling outplanting in February 2018 in a common garden site in semiarid SE Spain. In total, 600 acorns were randomly sowed and 300 nursery-grown seedlings were outplanted and studied until 2022. Mother tree and initial acorn mass were also monitored as additional variables in the analyses. Tree shelters consisted of closed plastic Tubes, Mixed tubes, Cork shelters, Tiles, and a Control with no shelter. Emergence rate was positively influenced by the Tube shelter (86%) as compared to the Control (64%), and especially by the initial acorn mass. By contrast, mother tree or year of sowing seemed to have no effect. The survival rate for the emerged acorns (88%) was statistically similar to that of outplanted seedlings (91%), and was unaffected by mother tree, tree shelter, or acorn mass. In terms of growth, the slenderness ratio (H:RCD) was considerably higher in seedlings from directly seeded acorns than for those that were outplanted. With the exception of Tile, all the shelters showed a higher slenderness ratio than the Control, especially the Tube shelter, which also showed a lower number of leaves and a lower aboveground dry biomass than the Control, Cork, and Tile shelters. Virtually no interactions were observed between the mother tree and the tree shelter. At harvesting, all the growth-related parameters were still strongly dependent on the acorn mass and the initial seedling features recorded after the first growing season. Resprouting rate and growth were also highly dependent on the acorn mass and the plant features at the beginning of the experiment and at harvesting. In summary, we did not find evidence to support tree shelters to improve the microclimate of holm oak seedlings both seeded or outplanted. Direct acorn seeding can be as successful as outplanting of nursery-grown seedlings. Selection of heavy acorns from mothers with a high germination and emergence rate is highly advisable.

Simulating micro-climatic effects of sky-gardens designed with middle-to-high rise buildings

In response to the growing demand for high-quality urban living environments, this research addresses the optimization of sky garden designs in mid-to-high-rise buildings, a topic that has not been thoroughly explored despite its potential for enhancing micro-environments. The primary aim of this study is to identify design strategies that maximize ecological benefits by evaluating a variety of sky garden configurations. Using Computational Fluid Dynamics (CFD), the study analyzed 96 different sky garden combinations, considering three building forms (square, rectangular, circular), four sky garden types (side, central, corner, peripheral), and four height levels (24, 44, 64, and 84 m). The simulations focused on key micro-climatic factors such as wind velocity and pressure, as well as heat effects from vegetation transpiration. Results indicate that square and rectangular buildings with central sky gardens at approximately 55 m provide significant environmental benefits, while circular buildings with peripheral sky gardens deliver the most optimal micro-climatic conditions across various heights and plant configurations. The key contribution of this research lies in establishing a basis for future design standards and regulations, offering a novel approach to maximizing the ecological and climatic advantages of sky gardens. This study's originality lies in its comprehensive evaluation of multiple design parameters and their combined impact on urban micro-climates, thereby providing valuable insights for architects and urban planners aiming to enhance urban sustainability and livability of mid-to-high-rise buildings.

Microclimate Effect on Cooling Energy for Buildings in Hot, Humid Climates: A Comparative Analysis of Shaded and Unshaded Environments

This paper explores the influence of microclimates on changes in air temperature and the often-overlooked aspect of their effect on energy savings across varying microclimatic conditions. The study compares the cooling energy requirements of two identical single-story buildings in distinct microclimates: one characterized by concrete ground devoid of shade and the other featuring soil ground with tree shade. Climatic environmental data were collected over 15 days in the concrete-exposed field and shaded area beneath the trees to conduct the investigation. These datasets were input into EnergyPlus 9.6 to model the energy demands and consumption of buildings subject to the specified climatic conditions. The validation of the simulated model against actual energy demand data from a classroom building demonstrated agreement. The findings reveal notable differences in air temperature, with the shaded area experiencing temperatures 0.8°C to 8.0°C lower than the concrete-exposed monitoring location. The building in the tree-shaded microclimate exhibited a lower peak cooling load than its concrete-exposed counterpart, resulting in a 35% reduction in the electrical energy requirements for the air-conditioning system. The study recommends implementing 0.08-m polyurethane insulation for the building walls and roof to equalize the energy demand and consumption of the concrete-exposed building with that of its shaded counterpart. Furthermore, building design in shaded areas can maximize the window glass area while consuming less energy than buildings on concrete-exposed grounds. The study advocates leveraging the microclimate associated with surrounding buildings in the design process to enhance the overall energy savings.

Application of an Empirical Model to Improve Maximum Value Predictions in CFD-RANS: Insights from Four Scientific Domains

This study introduces an empirical model designed to predict the maximum values of time-dependent data across four turbulence-related fields: hydrogen combustion in renewable energy systems, urban microclimate effects on cultural heritage, shipping emissions, and road vehicle emissions. The model, which is based on the mean, standard deviation, and integral time scale, employs two parameters: a fixed exponent ‘ν’ (0.3) reflecting time scale sensitivity, and a variable parameter ‘b’ that accounts for application-specific uncertainties. Integrated into the Computational Fluid Dynamics (CFD) framework, specifically the Reynolds-Averaged Navier–Stokes (RANS) methodology, the model addresses the RANS approach’s limitation in predicting extreme values due to its inherent averaging process. By incorporating the empirical model, this study enhances RANS simulations’ ability to predict critical values, such as peak hydrogen concentrations and maximum urban wind speeds, which is essential for safety and reliability assessments. Validation against experimental and numerical data across the four fields demonstrates strong agreement, highlighting the model’s potential to improve CFD-RANS predictions of extreme events. This advancement offers significant implications for future CFD-RANS applications, particularly in scenarios demanding fast and reliable maximum value predictions.

Diagnostic investigation of the wall paints conservative state in a hypogeal room of the archaeological park of Baia (Italy)

The present study investigated the correlation between the degradation processes of cultural heritage and the environmental parameters of the semi-confined site that houses it. The latter is a semi-underground room (nymphaeum) found in the Archaeological Park of Baia (Italy) dating back to the third century; it is decorated with marine motifs and painted with frescos techniques from the same period. Relative humidity and temperature were hourly registered, and the collected data were used to derive daily and annual profiles. The effects of microclimate induced degradation were investigated employing various techniques, such as Ion Chromatography for the chemical characterisation of deposits, and Thermography, for the individuation of biological layers. The data obtained showed that the underground environment, partially submerged by rising brackish water, was affected by the presence of biodeteriogens, whose distribution and growth is strongly favoured, above all, by the environmental parameters and by the substrate characteristics. All the data were then cross-referenced to obtain a complete knowledge of the conservation frameworks of the environments, essential to identify the most compatible and effective restoration methodologies to be applied in the conservation of the nymphaeum.

Optimizing green infrastructure strategies for microclimate regulation and air quality improvement in urban environments: A case study

With an increasing global urban population andassociated health concerns, understanding the effects of urban microclimate and air quality is crucial. This study aims to assess the influence of different types and locations of greenery, along with building heights and wind orientation, on urban canyon microclimate and air quality. Focusing on PM10, PM2.5, and NOx concentrations in a hot-arid district, the research employs simulation-based analysis. Results indicate that stepped buildings with green walls exhibit the highest temperature (18.02°C), while scenarios featuring two rows of deciduous trees showcase the lowest temperature (17.56°C) but higher pollution levels. Notably, scenarios lacking trees exhibit elevated temperatures. The study introduces a novel ventilation design pattern for effective air pollutant removal and proposes a scenario with extensive green coverage on streets, walls, and rooftops, incorporating appropriate planting techniques and plant selection. The findings offer valuable insights for urban designers and architects seeking to create more sustainable and environmentally friendly cities.

Testing Strategies for Planting Design in Urban Squares to Improve Human Comfort throughout the Seasons

Green urban squares are essential in densely built neighborhoods and enhance their quality of life. Investment in the greening of urban areas will have a beneficial impact, particularly regarding human thermal comfort. Smaller than parks, squares can be easily spread over the cities and should be part of any neighborhood. While the cooling effect of green squares during hot summer days is increasingly well established, microclimatic assessments during all seasons are still missing. This study aimed to determine whether it is possible to identify an optimal greenery design that maximizes human thermal comfort, as indexed by physiological equivalent temperature (PET), in temperate climates across all seasons. This study employed a “research by design” methodology, utilizing the micrometeorological simulation model ENVI-met to analyze the impact of greenery on PET improvement across different seasons. The objective was to identify the most effective combination of greenery for PET improvement. To achieve these objectives, two urban squares in Munich, Germany were selected. This selection was based on the assumption that typical greening practices, exemplified by the presence of trees, shrubs, and grass, would significantly impact urban squares and their microclimatic effects on human thermal comfort. The small square with a grass surface underneath trees, Alpenplatz, is highly influenced by the surrounding buildings, affecting the sky view factor (SVF), a crucial aspect of the urban environment. Marstallplatz, an open, large square that is not highly affected by urban morphology, was analyzed through simulation scenarios combining grass, shrubs, and trees. The results demonstrate that hot summer days are of primary concern for climate-sensitive urban square design in order to avoid health risks and thus need to be prioritized without compromising comfort for cold days. To attend to both needs, increasing the number of deciduous trees for shading during the day and the amount of grass to enhance air cooling at night are particularly effective. Nevertheless, microclimate design for the spring and autumn periods must also be considered, with the provision of adaptable opportunities for sheltered and sun-exposed spaces.

Wpływ mikroklimatu gorącego na funkcje psychomotoryczne pracowników

The effect of hot microclimate on psychomotor functions of employees For several years now, one of the most important harmful factors related to the work environment has been a hot microclimate. Additionally, due to climate changes, including an increase in the average air temperature, especially in summer, attention should be paid to people working in open spaces. Microclimate parameters affect not only on physiological responses of the human body, but also psychomotor efficiency, which translates into the number of errors made during work, and thus the safety of oneself and one's colleagues. The aim of the article is to indicate the impact of a hot microclimate (and so a high air temperature) on the psychomotor functions of workers. Expanding knowledge in this area may contribute to improving safety at work in hot microclimates. Keywords: air temperature, hot environment, hot microclimate, thermal load, psychomotor performance, cognitive function

Pengaruh Iklim Mikro dan Penggunaan Media Tanam yang Berbeda pada Pertumbuan Tanaman Melon Varietas Sweet Net

Melon are plants that are sensitive to environmental changes. Currently, developing technology for cultivating melons in greenhouses is used to modify the microclimate for the growth of melon plants. This research aims to determine the effect of microclimate and different types of planting media on growth response of sweet net variety melon plants that planted in the Politeknik Negeri Jember smart green house. The research was carried out in January – May 2024. The treatments tested consisted of two treatments, namely: the use of soil media+compos and cocopeat media which would be repeated 15 times. The parameters observed include microclimate (temperature and humidity) and also plant growth indicators including plant length and number of leaves, number of flowers, and potential weight of melon. The data obtained were analyzed using the T-test. The research results show that the microclimate inside the Politeknik Negeri Jember smart green house is still classified as an optimal microclimate to support the growth of melon plants. Apart from that, the use of cocopeat planting media was able to provide the best results for the length of the melon plants in the 4th to 6th week of observation, but there was no significant difference in the parameters of the number of leaves, number of flowers and potential weight of melon of. The use of cocopeat media and soil media are both good media in supporting the growth of melon plants in a greenhouse.

Navigating urban climate design implementation challenges: insights from Brisbane’s built environment experts

ABSTRACT Urban densification, intended to enhance efficiency, often exacerbates urban climate issues like diminished thermal and wind comfort. Despite substantial evidence on the climatic impacts of urbanization, integrating this knowledge into development practices remains difficult. This study investigates urban climate design in Brisbane, Australia through semi-structured interviews with built environment professionals. A qualitative thematic analysis uncovers several challenges: ambiguous planning codes, a knowledge gap on microclimate effects, short-term political and economic priorities, and a lack of robust technical methods in early design stages. Recommendations include technological development, raising public awareness, and incorporating climate-sensitive practices in urban planning and design.

Optimizing open-pit coal mining operations: Leveraging meteorological conditions for dust removal and diffusion

Dust pollution from Chinese open-pit coal mines (OPCMs) threatens the coexistence of resource development and environmental protection. This research introduces a new approach to designing OPCMs based on meteorological indicators for dust removal and diffusion. It analyzes the production, distribution, and dust emission features of large-scale OPCMs in China. The factors affecting dust dispersion and atmospheric pollution characteristics were also examined. The findings reveal a surge in the number and output of OPCMs, intensifying the conflict between resource development and environmental protection. Notably, over 80% of OPCMs are in arid and semi-arid regions, exacerbating the challenge. Microclimate effects, including circulation and inversion effects, further amplify dust pollution. Regional and seasonal dust pollution patterns were identified, with the southern region experiencing the highest pollution levels, followed by the northern and central regions. Seasonally, dust pollution exhibits the following pattern: winter > autumn > spring > summer. An alarming decline in atmospheric self-cleaning capacity over the past two decades underscores the pressing challenges ahead for dust control. The increase in air stagnation days/events highlights the urgency for effective dust prevention and control measures. This research suggests considering meteorological elements in OPCM design for dust control. Optimizing mining operations based on weather forecasts enables the utilization of natural conditions for effective dust prevention and control. The results provide insights for dust prevention and control in open-pit mines to foster green and climate-smart mining.

On the deduction and quantification of irruptive dynamics in mountain pine beetle population and proxy data

AbstractIn attempting to develop a coherent description of the irruptive dynamics of mountain pine beetle (MPB) in North America, we examined a range of cases where authors described the dependency of intrinsic population growth rates on population attack levels. In some cases, detailed population data were used, but in most cases, investigators relied on operational aerial detection survey data. We found that study conclusions varied significantly depending on the type of data analysed and the spatial and temporal dimensions of the monitoring program. The ability to detect an intrinsic Allee effect (i.e., positive density‐dependent growth for low and rising population densities) depended on the type and the intensity of the sampling effort and the extent of sampling in space and time. Consequently, not all studies were able to quantify the irruption threshold (i.e., the population density at which endemic populations may transition towards the epidemic state). Notably, in every study where an Allee effect was demonstrated, investigators also identified at least one extrinsic environmental factor (e.g., winter weather, summer drought, microclimatic effect) that was regulating its strength. Our results suggest that population surveys conducted from the ground are a necessary complement to aerial survey data if the goal is to make inferences about the irruptive potential for MPB populations and the role of environmental factors in shaping that irruptive potential.