International Journal of Biometeorology最新文献

The association of low-level ozone (O₃) exposure with the mortality risk of ischemic heart disease (IHD) and stroke remains to be investigated. This study aimed to investigate the relationship between low-level O₃ exposure and mortality risk of IHD and stroke in Yibin, a city in southwestern China. A Poisson distribution lagged nonlinear model was used to assess the effect of O₃ exposure on IHD and stroke mortality and to explore the susceptible population according to gender and age subgroups and the susceptible season according to seasonal subgroups and to analyse the health effects under low O₃ exposure compared with high O₃ exposure. The mean O₃ exposure concentration from 2014 to 2020 was approximately 48.3 μg/m3. There was a major lagged effect of O₃ exposure on IHD and stroke. For every 10.0 μg/m³ increase in O₃ concentration, the cumulative risks of death for the two diseases were 1.0211 (95% Confidence Interval [CI]: 1.0064, 1.0358) and 1.0211 (95% CI: 1.0064, 1.0357), respectively. The mortality risks of IHD and stroke for women were 1.0064 (95% CI: 1.0016, 1.0113) and 1.0030 (95% CI: 1.0008, 1.0051), and for those aged > 65 years, they were 1.0082 (95% CI: 1.0026, 1.0139) and 1.0018 (95% CI: 1.0002, 1.0034), and the mortality risks in the warm season were 1.0043 (95% CI: 1.0007, 1.0080) and 1.0038 (95% CI: 1.0005, 1.0072), respectively. The introduction of other pollutants (PM_2.5, PM₁₀, NO₂, CO) to construct a dual-pollutant model showed that the effect of O₃ on the mortality risk of IHD and stroke remained statistically significant. This study consolidates the evidence for a positive correlation between low-level O₃ exposure and the mortality risk of IHD and stroke. The findings provide preliminary exploratory insights into the potential impact of air pollution on these diseases, offering a valuable reference for future research.

Livestock production is increasingly at risk from rising temperatures under global warming. Despite this, how temperature increases impact the behavior of cattle on pasture is not fully understood. This research reports on patterns of beef cattle activity, including step counts and lying time, during the summer and fall grazing seasons of 2021, coincident with an unusual period of elevated temperatures and heat load within a northern temperate rangeland of Alberta, Canada. Beef heifers and first calf cows with calves at side were monitored using IceRobotics leg-mounted pedometers deployed from June 24 to August 26 in summer pasture, and August 27 to November 10 in fall pasture. Heat load conditions were quantified through the temperature-humidity index (THI), which has previously been reported to alter cattle behavior. Cattle exhibited marked diurnal shifts in activity patterns during elevated heat loading periods, increasing their activity (movement) at night and midday, with reduced activity in the morning and afternoon. While heifers had greater step counts in summer than cows, the reverse was true during fall, with cows being more active than heifers and having reduced lying times. A regression tree analysis indicated the specific thresholds for heat load (THI) that alter cattle activity were 54 (lower value) and 70 (upper value), below and above which, movement rates increased with greater heat loading. These results are useful for assessing cattle behavioral responses to weather conditions, including heat load. Further work is needed to understand how cattle activity under open-range grazing in temperate environments alter cattle behavior, stress and beef production outcomes, particularly in the face of escalating climate change.

Building morphological indicators are widely used for microclimate regulation, but their complexity often hinders practical understanding and application. This study aims to simplify multiple morphological indicators into a smaller set of factors, and demonstrates that the simplified factors still account for microclimate effects. The study was conducted in Changsha, China. Microclimate and morphological data were collected within buffer zones ranging from 30 to 200 m in radius. Exploratory Factor Analysis (EFA) was performed on up to 12 morphological indicators, and the resulting factor scores were analyzed through regression with microclimate indicators. The results confirmed that: (1) 6 to 9 morphological indicators can be reduced to 1 to 3 factors, retaining most of the original information. The factor extraction is influenced by both the morphological indicators and the buffer radius. (2) The factors significantly impact air temperature, relative humidity, wind speed, mean radiant temperature, and the Universal Thermal Climate Index, with the extent of influence varying across microclimate indicators and buffer radii. By consolidating the shared characteristics of multiple morphological indicators, this study offers a more concise and integrated approach for describing building morphology, and its essential relationship with the microclimate.

Balneotherapy (BT) is considered an effective, non-pharmacological approach, in the multimodal treatment of the Primary Fibromyalgia Syndrome (FS). However, the evidence of efficacy and tolerability of BT in FS is still limited. This is a prospective multi-center two-cohort observational study. The main aim will be the comparison of the Minimal Clinically Important Difference (according to Fibromyalgia Impact Questionnaire-FIQ) achievement in FS patients treated with BT vs standard care. Secondary objectives will be to assess: a) BT impact on pain, quality of life, anxiety and depression; b) the persistence of benefits in six weeks c) BT safety profile. All FS patients with a stable treatment in the past 3 months and a moderate to severe disease (FIQ score ≥ 39) will be enrolled after providing written informed consent. Patients will be divided into two Cohort: a) BT Cohort (i.e., BT in addition to standard care)-BTC; b) Control Cohort (i.e., only standard care)-SCC. There will be three assessments: baseline, two and six weeks (i.e., one month after BT end in BTC). At each of them the subject will fill in the following questionnaires: FIQ, VAS pain, Short Form Health Survey 16, State-Trait Anxiety Inventory and Center for Epidemiological Studies Depression Scale. We expect to observe a more relevant improvement of disease activity in BTC than in SCC. The positive effect may extend even to pain, quality of life, anxiety and depression. The short- and medium-term effects are likely to be similar, without any significant warning in terms of tolerability. Collected data, deriving from a large sample of patients, will provide a new insight of BT role in moderate to severe FS treatment. In particular, it will be possible to quantify the short and medium-term BT impact on disease activity and secondary symptoms related to FS.

The green dwarf coconut (Cocos nucifera L.) has an extreme economic importance in Brazil, especially in the state of Pará, the third largest national producer. The phenological aspects of these plants can undergo changes according to the environment to which they are subjected, so the objective was to determine the basal temperatures, quantify the duration of the reproductive phase and verify the effect of climatic seasonality on the thermal accumulation of the green dwarf coconut tree, in the northeast region of Pará, Brazil. The experiment was conducted at the Fazenda Reunidas Sococo, considering two different areas, one with irrigation and the other without water exchange. The experiment was carried out between September 2020 and February 2022, with phenological observations every 2 days, for a total of about 60 reproductive cycles in each area. The lower and upper basal temperatures for coconut cultivation corresponded to 10 °C and 33 °C, respectively, the average thermal demand found for the commercial reproductive cycle was 3866.2 °C day for the irrigated condition and 3696.3 °C day when rainfed. In a non-irrigated condition, the coconut tree has a well-defined seasonality of cycle length, indicating that greater accumulated rainfall guarantees longer cycles, both in days and degree-days, with their shortening associated with lower water availability. The crop prediction model using thermal units performed well. The results obtained facilitate the understanding of the impact of meteorological conditions on coconut production and assist in the management of the crop in the region.

Frequent drought events greatly decrease the gross primary productivity (GPP) and disturb the carbon dynamics of ecologically fragile grassland ecosystems. While GPP is controlled both by canopy structure-related fraction of absorbed photosynthetically active radiation and leaf physiology-related light use efficiency, the underlying mechanisms of drought-induced decline in photosynthetic capacity remain unclear in grassland ecosystems. Here, we used ground-observed maximum GPP based on flux tower (GPP_peak) and satellite-retrieved maximum solar-induced chlorophyll fluorescence (SIF_peak) within each year as the proxy of photosynthetic capacity of alpine grasslands (AG) and temperate grasslands (TG) in China. We first decomposed GPP_peak and SIF_peak into radiation, structure, and physiological components, and compared their relative changes in drought years versus normal years at both local and regional scales. Results showed that declines in GPP_peak and SIF_peak under drought were more pronounced in TG due to its more arid climates. In TG, canopy structure was the main component driving photosynthesis loss because of the smaller proportion of carbon allocation to leaves under drought. However, in AG, the decline in leaf physiology was the primary component. Structural equation modeling revealed that changes in structure and physiological components dominated the spatial variance of SIF_peak response to drought in TG and AG, respectively. The alteration in environmental factors under drought could explain most of the spatial variance of changes in canopy structure and leaf physiology. These findings enhance understanding of the mechanisms behind grassland photosynthetic response to drought, providing insights critical for predicting ecosystem carbon balance under climate change.

In recent decades, flash drought events have frequently occurred in the humid regions of southern China. Due to the sudden onset and rapid intensification of these droughts, they often cause severe damage to vegetation photosynthesis. However, our understanding of the spatiotemporal evolution characteristics of flash droughts across different vegetation types, as well as the response regularity of photosynthesis to flash droughts, especially early responses, remains limited. This study analyzes the spatiotemporal evolution characteristics of flash droughts for different vegetation types in the Middle and Lower Reaches of the Yangtze River Basin from 2000 to 2023. It uses solar-induced chlorophyll fluorescence (SIF) and fluorescence yield ([Formula: see text]) to explore the response regularity of vegetation photosynthesis to flash droughts, with a systematic analysis of the 2013 flash drought event. The results show that, over the past 24 years, the frequency of flash droughts for different vegetation types in the Middle and Lower Reaches of the Yangtze River Basin has decreased, but the total duration has increased, with forests experiencing the highest frequency of flash droughts, while cropland experiences the least. Cropland photosynthesis is the most sensitive to flash drought, showing an early response 8-16 days after the onset and reaching a negative anomaly between 24 and 32 days. Forests mainly show an early response between 16 and 24 days and a negative anomaly response between 32 and 40 days. During the 2013 flash drought, cropland showed an early response on the 10th day after the onset and a negative anomaly on the 26th day, while forest responses were later, with early responses on the 20th day and negative anomalies on the 36th day. These results align with long-term statistical data. This study contributes to a deeper understanding of vegetation photosynthesis response regularity to flash droughts and provides insights for developing effective flash drought management strategies.

This study aimed to examine the impact of climatic conditions on feed intake, body weight, and rectal temperature in horses residing in the hot Summer Mediterranean climate zone. Eight gelding Italian Saddle horses, with an average body weight of 427.78 ± 54.55 kg and aged between 10 and 13 years, participated in the research. All horses were individually housed in a paddock (800 m²/horse), and fed ad libitum. Food intake, body weight, and rectal temperature were recorded every 10 days at four 30-day collection periods in the year: January, April, July, and October. The formula adapted from Thom (Weatherwise, 12,57-61, 1959) was used to calculate the temperature-humidity index (THI). The total and daily average feeding intake was computed based on the recorded temperature and humidity for each season. No statistical difference among seasons and data points in the total and daily average feeding ingestion, body weight and rectal temperature were recorded. This study demonstrates that horses kept in paddocks and provided ad libitum access to uniformly high-quality hay exhibit consistent feed intake, body weight, and rectal temperature across different seasons, with minimal inter- and intra-subject variability in the hot Mediterranean summer climate.