Search Results (334)

Nature-based Solutions (NbS) are essential for peri-urban resilience; however, a critical research gap exists regarding the lack of species-specific eco-physiological validation for interventions within complex biocultural systems. This study addresses this gap by assessing the vulnerability of Quararibea funebris, a shade-tolerant tree and biocultural keystone for the tejate economy in Oaxaca, Mexico, currently caught in an anthropogenic ecological trap. A mixed-methods approach was employed, integrating a geospatial analysis of land-use change (1992–2021), microclimatic monitoring, and ethnographic assessment of gendered management. Results reveal the loss of 1552 ha of forest buffer, which has degraded the thermal niche below the species optimum. Urban specimens are subjected to a Daily Light Integral exceeding 38 mol m⁻² d⁻¹, triggering biometric stunting and oxidative stress. Furthermore, given that seed recalcitrance limits ex situ conservation, the species’ persistence relies strictly on a domestic monopoly of irrigation managed by women, who effectively subsidize the environmental deficit. The study concludes that the current backyard conservation model has hit its ecological ceiling; sustainability requires a transition toward landscape-scale NbS—specifically biocultural corridors governed by local female knowledge—to restore the multi-strata canopy required to regulate the species’ eco-physiological limits. Full article

Microstegium vimineum (Japanese stiltgrass) is one of the most invasive plant species in the eastern United States, posing a consistent problem to practitioners working in stream restoration and often necessitating treatment using non-selective herbicides to reduce invasion. Herbicide use frequently results in collateral damage to desirable native species and can lead to reinvasion after treatment. This study evaluated alternatives to herbicide referred to collectively as cultural controls, the use of which draws conceptually from the interaction of stress and disturbance in plant communities that predicts reduced invasion and increased competitive success of native species with higher levels of environmental stress. We tested several preventative cultural approaches, including (intended stressor in parentheses): (1) canopy shade (light limitation), (2) sawdust soil amendments (short-term nitrogen limitation), (3) wood mulch soil amendments (longer-term nitrogen limitation), and (4) double seeding rates (native species competition), as well as a combination of these treatments. Over a two-year field study within a restored stream corridor, we found that high carbon: nitrogen ratio soil amendments such as sawdust were the most effective at attenuating M. vimineum invasion and that shade promoted native species competition with this invader. Our results suggest a set of best practices that stream restoration practitioners could consider during the design and construction phases of a stream restoration project, particularly on sites with increased risk of M. vimineum incursion. Full article

Tree peony (Paeonia sect. Moutan) is one of the most important traditional ornamental woody flowers in China. However, its cultivation is often challenged by intense light and high temperatures during summer, leading to severe photo-oxidative damage and leaf senescence. In this study, we investigated the protective effects of polyolefin (PO) film on potted tree peony leaves under summer intense light and high temperature stress. Using tree peony ‘Luoyanghong’ as experimental material, we systematically compared the effects of two controls under natural light (CK1 and CK2, housed in separate greenhouses), single-layer PO film (PO1), and double-layer PO film (PO2) treatments. Microenvironment monitoring showed that single-layer and double-layer PO films reduced light intensity by 21% and 49%, respectively, while having limited effects on temperature. Morphological and physiological analyses indicated that PO film treatments effectively alleviated leaf yellowing and withering, maintained normal physiological morphology, and increased chlorophyll (Chl) and carotenoid (Car) content. The net photosynthetic rates of PO1 and PO2 plants were 18–36% higher than those of the control groups (CK1 and CK2). Evans blue and NBT staining revealed that PO film reduced cellular damage and reactive oxygen species (ROS) accumulation, while decreasing malondialdehyde (MDA) levels and increasing catalase (CAT) activity. Furthermore, qRT-PCR results showed that stress-responsive genes (Hsp70, Hsp90, and ATG5) and photosynthetic genes (RbcS and RbcL) were upregulated under PO film treatment. Principal component analysis (PCA) indicated that high light intensity, rather than temperature, was the primary factor causing leaf damage in potted tree peonies. The results show that PO film is an effective and low-cost agronomic measure, which can alleviate the intense light stress under high temperature conditions, relieve photo-oxidative damage, maintain photosynthetic performance, and increase the survival rate of potted tree peonies in summer. Full article

Christmas tree growers are concerned with improving establishment of their plantations. Here, we report the results of a series of on-farm trials conducted with grower-cooperators in the Pacific Northwest (PNW) and Great Lakes (Michigan—MI) regions to determine the efficacy of treatments at planting on improving tree survival and growth in Christmas tree plantations. Cooperating growers planted species that were typical for each region (Fraser fir in the Great Lakes and Douglas-fir and noble fir in the PNW) and managed the plantings using standard cultural practices, aside from test treatments. Test treatments varied between locations and years but included wood chip mulch, shade blocks, an anti-transpirant, biochar, fertilizers, and various root dips including polymer gels, mycorrhizae, and bio-stimulants. Overall, treatments that directly modified the tree environment (i.e., mulch and shade blocks) provided the most consistent benefit to tree survival and growth. In Michigan, mulching increased survival by 5% on non-irrigated farms and increased second-year shoot growth by ~3 cm. In the PNW trials, mulching increased survival of noble fir seedlings more than Douglas-fir seedlings. Installing controlled release fertilizer packets at planting increased initial growth of Douglas-firs. Application of root dips prior to planting did not improve tree survival or growth relative to dipping tree roots in water (control). Based on our results, we conclude that treatments that conserve soil moisture (mulch) or reduce tree water loss (shade blocks) offer the most direct opportunity for growers to improve initial tree survival and growth. Full article

With accelerating urbanization and climate change, outdoor thermal comfort (OTC) in high-intensity urban blocks presents a critical challenge. While existing studies have established the general correlation between morphology and microclimate, most remain descriptive and lack a systematic framework to quantitatively integrate the non-linear coupled effects between multi-dimensional morphological variables and green infrastructure. To address this, this study proposes an automated performance-based design (PBD) framework for urban morphology optimization in Shenzhen. Unlike traditional simulation-based analysis, this framework serves as a generative tool for urban renewal planning. It integrates a multi-dimensional design element system with a genetic algorithm (GA) workflow. Analysis across four urban typologies demonstrated that the Full Enclosure layout is the most effective strategy for mitigating thermal stress, achieving a final optimized UTCI of 37.15 °C. Crucially, this study reveals a non-linear synergistic mechanism: the high street aspect ratios (H/W) of enclosed forms act as a “radiation shelter”, which amplifies the cooling efficiency of green infrastructure (contributing an additional 1.79 °C reduction). This research establishes a significant, strong negative correlation between UTCI and the combined factors of building density and green shading coverage. The results provide quantifiable guidelines for retrofitting existing high-density districts, suggesting that maximizing structural shading is prioritized over ventilation in ultra-high-density, low-wind climates. Full article

Invasive plant species persist under environmental conditions due to phenotypic plasticity, which allows them to cope with conditions such as herbivory, competition, and resource availability. However, plant responses to individual and combined stressors are variable. In addition, fluctuating asymmetry (FA) has been proposed as an indicator of plant stress, although its reliability remains debated, and few studies have evaluated its responses under interacting stressors. We evaluated, in two greenhouse experiments, the isolated and combined effects of herbivory and shading; and belowground intraspecific competition and fertilization on performance, trait plasticity, and leaf FA in seedlings of the invasive plant Tithonia diversifolia. Shading reduced shoot biomass, but promoted plastic adjustments in architectural, photosynthetic, and leaf structural traits that enhance light capture, and also increased FA. Herbivory interaction with shade induced high leaf mass per area of plants. In contrast, high herbivory and intraspecific competition consistently reduced plant performance across multiple traits. Fertilization enhanced overall performance and mitigated the negative effects of herbivory and competition. Overall, our results emphasize the need to consider interacting environmental factors when assessing invasive plant performance and plasticity. Furthermore, FA showed inconsistent responses across treatments, suggesting its limited reliability as a biomarker of isolated and combined environmental stress. Full article

Cocoa production in West Africa supplies most of the global demand but is increasingly constrained by yield stagnation, soil degradation, disease pressure, and climate variability. This review examines how integrating regenerative agriculture (RA) with unmanned aerial systems (UAS) and artificial intelligence (AI) can support more precise and resilient cocoa management across heterogeneous smallholder landscapes. A PRISMA-guided systematic review of peer-reviewed literature published between 2000 and 2024 was conducted, yielding 49 core studies analyzed alongside supporting evidence. The synthesis evaluates regenerative agronomic outcomes, UAV-derived multispectral, thermal, and structural diagnostics, and AI-based analytical approaches for stress detection, yield estimation, and management zoning. Results indicate that regenerative practices consistently improve soil health and yield stability, while UAS data enhance spatial targeting of rehabilitation, shade management, and stress interventions. AI models further improve predictive capacity and decision relevance when aligned with data availability and institutional context, although performance varies across systems. Reported yield stabilization or improvement typically ranges from 12–30% under integrated approaches, with concurrent reductions in fertilizer and water inputs where spatial targeting is applied. The review concludes that effective scaling of RA–UAS–AI systems depends less on technical sophistication than on governance arrangements, extension integration, and cooperative service models, positioning these tools as enabling components rather than standalone solutions for sustainable cocoa intensification. Full article

Climate change has intensified summer drought and high solar radiation in Mediterranean ecosystems, generating abiotic stress that limits the establishment of riparian species. We conducted a nursery experiment to evaluate the effects of two levels of water availability and light intensity on the growth and physiological responses of two native riparian species from Mediterranean Chile: Drimys winteri and Persea lingue. A bi-factorial design combined two irrigation treatments (well-watered and water restriction) and two light intensity levels manipulated through a light protection treatment (20% shade mesh and full light exposure). Water restriction was applied gradually until 15–20% (v/v) substrate moisture, defined as maximum water restriction, followed by rehydration. Morphological variables (height, root collar diameter, and shoot-to-root ratio) and physiological traits (predawn water potential, chlorophyll fluorescence, and electron transport rate) were measured. Growth responses were affected by the light protection treatment, which promoted a significant height growth in both species. Water stress affected the global response of both species but they differed in their post-stress hydraulic recovery: P. lingue fully recovered its predawn water potential, whereas Drimys winteri did not. Our study provides measurable and quantifiable values that demonstrate the sensitivity of these species to water stress. Full article

Heat stress represents a pervasive welfare challenge for beef cattle and other species in tropical and subtropical regions. While its physiological and production impacts are well-documented, quantitative measures of the welfare impact of heat stress remain absent. This study provides the first quantification of the welfare impact of heat stress in beef cattle (mostly Nelore), estimated as cumulative time in thermal discomfort of four intensities (Annoying, Hurtful, Disabling, Excruciating) using the Welfare Footprint Framework. We analyzed climate data from 636 locations over five years across major beef production areas in Brazil, Argentina, Colombia, Paraguay, and Uruguay. Daily heat stress episodes and chronic heat stress exposure were assessed, respectively, using Comprehensive Climate Index (CCI) levels and the Annual Thermal Load metric, which sums daily excesses above a threshold of thermal comfort (CCI = 30 °C) throughout the year, classifying locations into five risk categories. Welfare impacts were estimated for thirteen heat stress scenarios modeled by considering each CCI level within each thermal risk category. Beef cattle in moderate-risk regions were estimated to experience primarily mild thermal discomfort for an average of 5 h daily. This duration increased to an average of 7 h daily in high-risk areas, of which 4.5 h in moderate to intense thermal discomfort (Hurtful or higher). Very high-risk regions reached 10 h of daily thermal discomfort, while extreme-risk regions showed beef cattle facing heat stress for over 11 h on 307 days annually, including over 3 h per day under severe thermoregulatory effort. Overall, 65% of animals were in regions of high thermal risk or above, experiencing between 280 and 2800 h annually in moderate to intense thermal discomfort—a magnitude that places heat stress among the most significant welfare challenges in animal production. Shade provision reduced time in severe discomfort of Disabling intensity by 85% (from 578 to 83 h annually), with economic returns of US$12–16 per animal and payback periods of approximately 16 months. By quantifying welfare impacts as cumulative time in thermal discomfort, shade provision emerges as one of the most effective welfare interventions available for beef cattle, and likely other grazing ruminants, in tropical and subtropical regions. Full article

In Mediterranean cities, high solar radiation combined with limited shading and vegetation intensifies the urban heat island (UHI) phenomenon. As the road network often covers a large portion of the cities’ surfaces and is mostly constructed using asphalt pavements, it can significantly affect the urban microclimate, leading to low thermal comfort and increased energy consumption. Recycled and waste materials are increasingly used in the construction of pavements in accordance with the principle of sustainability for minimizing waste and energy to produce new materials based on a circular economy. The scope of this study is to evaluate the effect of recycled or waste materials used in road pavements on the urban microclimate. The surface and ambient temperature of urban pavements constructed with conventional asphalt and recycled/waste-based mixtures are assessed through simulation. Two study areas comprising large street junctions near metro stations in the city of Thessaloniki, in Greece, are examined under three scenarios: a conventional hot mix asphalt, an asphalt mixture containing steel slag, and a high-albedo mixture. The results of the research suggest that the use of steel slag could reduce the air temperature by 0.9 °C at 15:00, east European summer time (EEST), while the high-albedo scenario could reduce the ambient temperature by 1.6 °C at 16:00. The research results are useful for promoting the use of recycled materials, not only as a means of sustainably using resources but also for the improvement of thermal comfort in urban areas, the mitigation of the UHI effect, and the reduction of heat stress for human health. Full article

Historic arcades in shaded street canyons may act as passive microclimate infrastructure. We monitored paired arcade–open points along two arcaded streets in Haikou, China, under clear summer conditions, recording hourly microclimate from 09:00 to 21:00. From these data we derived mean radiant temperature (Tmrt) and the Universal Thermal Climate Index (UTCI), tested main and interaction effects of space (arcade vs. open) and orientation (east–west vs. north–south), examined relations with sky view factor (SVF), and quantified exceedances of health-relevant thresholds using wet-bulb globe temperature (WBGT) and degree-hours. Arcades consistently lowered thermal exposure, with the largest benefits around midday–afternoon; the daily mean UTCI reduction was ~4.4 °C relative to adjacent open points. Orientation modulated benefits: east–west segments showed larger marginal reductions, and orientation differences were markedly compressed beneath arcades. SVF correlated positively with Tmrt and thermal stress but contributed little additional explanatory power after accounting for space and orientation, indicating geometric shielding as a primary mechanism. High-risk WBGT windows (≥32 °C) were strongly reduced under arcades, and day–night degree-hour summaries indicated net improvement. We conclude that historic arcades provide measurable thermal protection while preserving urban form, supporting their dual role as cultural heritage and passive climate-adaptation assets. Full article

Agrivoltaics (APV) offers a promising dual land-use solution for food and energy production, yet empirical data regarding its impact on leguminous crops in tropical monsoon climates remain limited. This study evaluated the microclimate, growth, and yield of soybean (Glycine max) under an APV system compared to an open-field control during the wet and dry seasons in Bogor, Indonesia. The APV structure reduced incident solar radiation by approximately 35%, significantly lowering soil temperatures and maintaining higher soil moisture across both seasons. In the wet season, the APV treatment significantly increased grain yield (3528.8 vs. 1708.3 kg ha⁻¹, +106%) relative to the open field by mitigating excessive heat and radiative loads, which enhanced pod retention. In the dry season, APV maintained a yield advantage (2025.6 vs. 1724.4 kg ha⁻¹, +17%), driven by improved water conservation and a higher harvest index. Notably, shading did not delay phenological development or hinder vegetative growth in either season. These findings demonstrate that APV systems can contribute to sustainably higher yields and stability in tropical environments by buffering against season-specific environmental stresses, suggesting a viable pathway for sustainable agricultural intensification in equatorial regions. Full article

The three key design criteria for nearly zero-energy buildings (nZEBs) and climate-neutral buildings are minimizing energy use, ensuring high occupant comfort, and reducing environmental impact. Thermal comfort is one of the main components of indoor environmental quality (IEQ), strongly affecting occupants’ health, well-being, and productivity. As energy-efficiency requirements become more demanding, the appropriate selection of heating systems, their automated control, and the management of solar heat gains are becoming increasingly important. This study investigates the influence of two low-temperature radiant heating systems—underfloor and wall-mounted—and the use of Venetian blinds on perceived thermal comfort in a highly glazed public nZEB building located in a densely built urban area within a temperate climate zone. The assessment was based on the PMV (Predicted Mean Vote) index, commonly used in IEQ research. The results show that both heating systems maintained indoor conditions corresponding to comfort or slight thermal stress under steady state operation. However, during periods of strong solar exposure in the room without blinds, PMV values exceeded 2.0, indicating substantial heat stress. In contrast, external Venetian blinds significantly stabilized the indoor microclimate—reducing PMV peaks by an average of 50.2% and lowering the number of discomfort hours by 94.9%—demonstrating the crucial role of solar protection in highly glazed spaces. No significant whole-body PMV differences were found between underfloor and wall heating. Overall, the findings provide practical insights into the control of thermal conditions in radiant-heated spaces and highlight the importance of solar shading in mitigating heat stress. These results may support the optimization of HVAC design, control, and operation in both residential and non-residential nZEB buildings, contributing to improved occupant comfort and enhanced energy efficiency. Full article

The microclimate of traditional blocks, a key component of urban fabric, directly affects the overall urban thermal environment. Creating a suitable microclimate is crucial for improving urban living quality. Field measurements, ENVI-met simulations, and the PET index were used to analyze the spatiotemporal variations and core drivers of thermal comfort. Temporally, five open space types showed a unimodal “rise–stabilization–fall” PET curve, with peak heat stress occurring at 11:00–14:00. Courtyards heated fastest, but green spaces had the most stable thermal environment because trees provided shading and transpiration for gentle cooling. Spatially, thermal comfort varied significantly. For example, green spaces rich in trees performed best (PET 5–8 °C lower than pure grassland), while squares and courtyards faced severe midday heat stress (PET mostly moderate or above). Alley comfort depended on aspect ratio and orientation—north–south alleys with an aspect ratio > 2 were 2–3 °C cooler than open spaces, but east–west or narrower alleys (aspect ratio < 1.5) and low-enclosed courtyard control apply to southern Hunan’s hot-humid zone. However, the synergistic principles can be extended to similar southern regions, providing technical reference for traditional block livability and climate-resilient cities. Full article

Vegetation phenology significantly influences urban microclimate and thermal comfort in cold regions, yet its quantitative impact—specifically the potential of deciduous trees to enhance winter solar access—remains underexplored. This study investigates how seasonal vegetation changes affect thermal conditions in an urban plaza. Field measurements were conducted at Beiyang Plaza, Tianjin University, during the autumn–winter transition. High-precision Sky View Factors (SVF) were extracted from panoramic images using a deep learning-based semantic segmentation model (PSPNet), validated against field observations. The Universal Thermal Climate Index (UTCI) was calculated to assess thermal stress. Results indicate that the leaf-off phase significantly increases SVF, shifting the radiative balance. Areas experiencing phenological changes exhibited a marked improvement in UTCI, effectively alleviating cold stress by maximizing solar gain. Advanced statistical models (ARIMAX and GAM) confirmed that, after controlling for background climatic variations, the positive effect of vegetation phenology on thermal comfort is statistically significant. These findings challenge the traditional focus on summer shading, highlighting the “winter-warming” potential of deciduous trees and providing quantitative evidence for climate-responsive urban design. Full article