climate

气候
  • 文章类型: Journal Article
    波斯小鹿或美索不达米亚小鹿(DamaMesopotamica,布鲁克1875),具有重要生态意义的物种,在伊朗面临灭绝的威胁。一种保护策略涉及将波斯鹿转移到伊朗各地的封闭地区,在那里,他们得到了免受外部威胁的保护,并得到了人类看护者的基本护理。当人类看护者努力满足他们的需求并减轻外部威胁时,气候变量现在可能成为影响封闭地区人口动态的关键因素。这项研究旨在评估波斯鹿种的原始区域(Dez和Karkheh)与11个新封闭区域之间的气候生态位相似性。为了实现这一点,我们使用气候数据和生态位建模(ENM)技术来评估12个地区之间的气候变化。我们利用环境等效性测试来确定区域对的环境空间是否表现出显着差异,以及这些空间是否可以互换。在接下来的步骤中,还进行了外推分析,以探索与伊朗其他地区不相似的原始休耕鹿栖息地的气候条件。我们的结果揭示了原始地区和所有易位地区之间的气候条件存在显着差异。根据对特定封闭地区人口增长的观察,在这些地区,易位的鹿种群蓬勃发展,我们假设该物种可能在伊朗表现出非平衡分布。因此,这些新的区域可能被视为该物种潜在气候生态位的一部分。外推分析表明,对于伊朗的很大一部分,外推预测对于波斯休养鹿的易位是高度不确定的,并且可能不可靠。然而,迁移努力的主要目标仍然是建立能够在封闭区域以外的自然区域繁荣发展的自我维持的波斯鹿种群,从而确保它们的长期生存,并有助于保护工作。评估新易位物种的成功需要额外的时间,观察到不同程度的成功。在某些封闭地区的物种生长速度低于预期的情况下,谨慎考虑可能导致人口减少的气候变量。此外,为了未来的易位,我们建议选择与该物种表现出增长率的地区气候相似的地区。
    The Persian fallow deer or Mesopotamian fallow Deer (Dama mesopotamica, Brook 1875), a species of significant ecological importance, had faced the threat of extinction in Iran. One conservation strategy involved the translocation of Persian deer to enclosed areas across Iran, where they were afforded protection from external threats and provided with essential care by human caretakers. While human caretakers diligently attend to their needs and mitigate external threats, climate variables may now become critical factors affecting population dynamics in enclosed areas. This study aims to assess the similarity in climate niches between the original area (Dez and Karkheh) of the Persian deer species and 11 newly enclosed areas. To achieve this, we employed climate data and ecological niche modeling (ENM) techniques to assess the variations in climate among 12 areas. We utilized the environmental equivalency test to determine whether the environmental spaces of area pairs exhibit significant differences and whether these spaces are interchangeable. Extrapolation analyses were also constructed in the next steps to explore climatic conditions in original fallow deer habitats that are non-analogous to those in other parts of Iran. Our results reveal significant disparities in climate conditions between the original and all translocated areas. Based on observations of population growth in specific enclosed areas where translocated deer populations have thrived, we hypothesize that the species may demonstrate a non-equilibrium distribution in Iran. Consequently, these new areas could potentially be regarded as part of the species\' potential climate niche. Extrapolation analysis showed that for a significant portion of Iran, extrapolation predictions are highly uncertain and potentially unreliable for the translocation of Persian fallow deer. However, the primary objective of translocation efforts remains the establishment of self-sustaining populations of Persian deer capable of thriving in natural areas beyond enclosed areas, thus ensuring their long-term survival and contributing to preservation efforts. Evaluating the success of newly translocated species requires additional time, with varying levels of success observed. In cases where the growth rate of the species in certain enclosed areas falls below expectations, it is prudent to consider climate variables that may contribute to population declines. Furthermore, for future translocations, we recommend selecting areas with climate similarities to regions where the species has demonstrated growth rates.
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  • 文章类型: Journal Article
    背景:三带囊库蚊在中国分布广泛,从南面的海南岛到北面的黑龙江,覆盖热带,亚热带,和温带气候区。三带库蚊携带19种虫媒病毒。它是日本脑炎病毒(JEV)的主要载体,严重威胁人类健康。了解环境因素对三带库蚊的影响可以为其种群结构或隔离模式提供重要的见解。目前尚不清楚。
    结果:总计,在552个扩增序列中检测到138个COI单倍型,单倍型多样性(Hd)值从温带(0.534)增加到热带(0.979)。单倍型系统发育分析表明,单倍型分为两个高支持进化分支。温带种群主要分布在进化分支II中,显示出与热带/亚热带种群的遗传隔离,群体之间的基因流动较少。HNQH(琼海)和HNHK(海口)人群的中性检测结果均为阴性(P<0.05),表明种群中存在许多低频突变,并且种群可能处于扩展过程中。此外,Wolbachia感染仅在SDJN(济宁)中检测到(2.24%),所有Wolbachia基因型都属于超群B。为了了解环境因素对蚊媒病毒的影响,我们在山东省三个生态环境中检测了三带钩状库蚊的感染情况。我们发现,与灌溉渠地区相比,莲池中的三带囊库蚊的JEV感染发生率明显更高。在这项研究中,JEV的总感染率为15.27/1000,提示目前山东省发生乙型脑炎的风险.
    结论:热带和亚热带三带囊库蚊种群具有较高的遗传多样性,这些气候条件为三带囊库蚊的建立和扩展提供了巨大的优势。在不同的生态条件下,三带囊库蚊野生种群的JEV感染率存在差异。我们的结果表明遗传分化的复杂相互作用,人口结构,和环境因素在塑造三带囊库蚊动力学中的作用。Wolbachia在野生种群中的低患病率可能反映了最近在三带囊库蚊中存在Wolbachia入侵。
    BACKGROUND: Culex tritaeniorhynchus is widely distributed in China, from Hainan Island in the south to Heilongjiang in the north, covering tropical, subtropical, and temperate climate zones. Culex tritaeniorhynchus carries 19 types of arboviruses. It is the main vector of the Japanese encephalitis virus (JEV), posing a serious threat to human health. Understanding the effects of environmental factors on Culex tritaeniorhynchus can provide important insights into its population structure or isolation patterns, which is currently unclear.
    RESULTS: In total, 138 COI haplotypes were detected in the 552 amplified sequences, and the haplotype diversity (Hd) value increased from temperate (0.534) to tropical (0.979) regions. The haplotype phylogeny analysis revealed that the haplotypes were divided into two high-support evolutionary branches. Temperate populations were predominantly distributed in evolutionary branch II, showing some genetic isolation from tropical/subtropical populations and less gene flow between groups. The neutral test results of HNQH (Qionghai) and HNHK(Haikou) populations were negative (P < 0.05), indicating many low-frequency mutations in the populations and that the populations might be in the process of expansion. Moreover, Wolbachia infection was detected only in SDJN (Jining) (2.24%), and all Wolbachia genotypes belonged to supergroup B. To understand the influence of environmental factors on mosquito-borne viruses, we examined the prevalence of Culex tritaeniorhynchus infection in three ecological environments in Shandong Province. We discovered that the incidence of JEV infection was notably greater in Culex tritaeniorhynchus from lotus ponds compared to those from irrigation canal regions. In this study, the overall JEV infection rate was 15.27 per 1000, suggesting the current risk of Japanese encephalitis outbreaks in Shandong Province.
    CONCLUSIONS: Tropical and subtropical populations of Culex tritaeniorhynchus showed higher genetic diversity and those climatic conditions provide great advantages for the establishment and expansion of Culex tritaeniorhynchus. There are differences in JEV infection rates in wild populations of Culex tritaeniorhynchus under different ecological conditions. Our results suggest a complex interplay of genetic differentiation, population structure, and environmental factors in shaping the dynamics of Culex tritaeniorhynchus. The low prevalence of Wolbachia in wild populations may reflect the recent presence of Wolbachia invasion in Culex tritaeniorhynchus.
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  • 文章类型: Journal Article
    背景:气候变化对健康的影响越来越大,特别是撒哈拉以南非洲的农村人口,因为他们的适应资源有限。理解这些影响仍然是一个挑战,因为对这些人群的生命体征的连续监测是有限的。可穿戴设备(可穿戴设备)提供了一种可行的方法来实时研究这些对人类健康的影响。
    目的:本研究的目的是评估消费级可穿戴设备在测量天气暴露对生理反应(包括活动,心率,壳体温度,和睡眠)肯尼亚西部农村人口,并确定与天气暴露相关的健康影响。
    方法:我们在肯尼亚西部进行了一项观察性案例研究,在3周内利用可穿戴设备连续监测各种健康指标,例如步数,睡眠模式,心率,和身体外壳温度。此外,当地气象站提供了有关降雨和热量等环境条件的详细数据,每15分钟测量一次。
    结果:我们的队列包括83名参与者(42名女性和41名男性),平均年龄33岁。我们观察到步数与最大湿球温度之间呈正相关(估计值0.06,SE0.02;P=.008)。尽管夜间最低气温和热指数与睡眠时间呈负相关,这些没有统计学意义。在其他应用模型中没有发现显著的相关性。在204天的194天(95.1%)记录了警告热指数水平。204天中有16天(7.8%)发生了暴雨(>20毫米/天)。尽管47台设备中有10台(21%)出现故障,睡眠和步数的数据完整性较高(平均82.6%,SD21.3%,平均值86.1%,SD18.9%,分别),但心率低(平均7%,SD14%),成年女性的心率数据完整性明显高于男性(双侧t检验:P=.003;Mann-WhitneyU检验:P=.001)。车身外壳温度数据达到36.2%(SD24.5%)的完整性。
    结论:我们的研究为肯尼亚农村地区天气暴露对健康的影响提供了细致的理解。我们的研究的可穿戴设备的应用揭示了身体活动水平和高温胁迫之间的显著相关性,与其他表明在较热条件下活动减少的研究相反。这种差异要求进一步调查独特的社会环境动态,特别是在撒哈拉以南非洲地区。此外,在热引起的睡眠中断中观察到的非重要趋势暴露了对局部气候变化缓解策略的需求,考虑到睡眠在健康中的重要作用。这些发现强调需要针对具体情况的研究,以便为容易受到气候变化不利健康影响的地区的政策和实践提供信息。
    BACKGROUND: Climate change increasingly impacts health, particularly of rural populations in sub-Saharan Africa due to their limited resources for adaptation. Understanding these impacts remains a challenge, as continuous monitoring of vital signs in such populations is limited. Wearable devices (wearables) present a viable approach to studying these impacts on human health in real time.
    OBJECTIVE: The aim of this study was to assess the feasibility and effectiveness of consumer-grade wearables in measuring the health impacts of weather exposure on physiological responses (including activity, heart rate, body shell temperature, and sleep) of rural populations in western Kenya and to identify the health impacts associated with the weather exposures.
    METHODS: We conducted an observational case study in western Kenya by utilizing wearables over a 3-week period to continuously monitor various health metrics such as step count, sleep patterns, heart rate, and body shell temperature. Additionally, a local weather station provided detailed data on environmental conditions such as rainfall and heat, with measurements taken every 15 minutes.
    RESULTS: Our cohort comprised 83 participants (42 women and 41 men), with an average age of 33 years. We observed a positive correlation between step count and maximum wet bulb globe temperature (estimate 0.06, SE 0.02; P=.008). Although there was a negative correlation between minimum nighttime temperatures and heat index with sleep duration, these were not statistically significant. No significant correlations were found in other applied models. A cautionary heat index level was recorded on 194 (95.1%) of 204 days. Heavy rainfall (>20 mm/day) occurred on 16 (7.8%) out of 204 days. Despite 10 (21%) out of 47 devices failing, data completeness was high for sleep and step count (mean 82.6%, SD 21.3% and mean 86.1%, SD 18.9%, respectively), but low for heart rate (mean 7%, SD 14%), with adult women showing significantly higher data completeness for heart rate than men (2-sided t test: P=.003; Mann-Whitney U test: P=.001). Body shell temperature data achieved 36.2% (SD 24.5%) completeness.
    CONCLUSIONS: Our study provides a nuanced understanding of the health impacts of weather exposures in rural Kenya. Our study\'s application of wearables reveals a significant correlation between physical activity levels and high temperature stress, contrasting with other studies suggesting decreased activity in hotter conditions. This discrepancy invites further investigation into the unique socioenvironmental dynamics at play, particularly in sub-Saharan African contexts. Moreover, the nonsignificant trends observed in sleep disruption due to heat expose the need for localized climate change mitigation strategies, considering the vital role of sleep in health. These findings emphasize the need for context-specific research to inform policy and practice in regions susceptible to the adverse health effects of climate change.
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  • 文章类型: Journal Article
    本文介绍了一种通过将聚类策略与回归模型集成并利用气象数据来模拟尼日利亚疟疾发病率的新方法。通过使用聚类技术将数据集分解为多个子集,我们增加了解释变量的数量,并阐明了天气在预测不同发病率数据范围中的作用.我们的聚类集成回归模型,伴随着最优障碍,提供有关疟疾发病率与降雨和温度等既定影响天气因素之间复杂关系的见解。我们探索两种模式。第一个模型结合了滞后发生率和个体特异性效应。第二个模型只关注天气成分。模型的选择取决于决策者的优先事项。推荐模型一用于更高的预测精度。此外,我们的发现揭示了疟疾发病率的显著差异,特定于某些地理集群,而不仅仅是观测到的天气变量可以解释的。值得注意的是,降雨和温度在不同的发病率集群中表现出不同的边际效应,表明它们对疟疾传播的不同影响。高降雨量与低发病率相关,可能是由于它在冲洗蚊子繁殖场所中的作用。另一方面,温度不能预测高发病例,这表明温度以外的其他因素也会导致高病例。我们的研究解决了疟疾发病率综合模型的需求,特别是在尼日利亚等疾病仍然流行的地区。通过将聚类技术与回归分析相结合,我们对预定的天气因素如何影响疟疾传播提供了细微差别的理解。这种方法有助于公共卫生当局实施有针对性的干预措施。我们的研究强调了在疟疾控制工作中考虑当地环境因素的重要性,并强调了基于天气的预测对主动疾病管理的潜力。
    This paper introduces a novel approach to modeling malaria incidence in Nigeria by integrating clustering strategies with regression modeling and leveraging meteorological data. By decomposing the datasets into multiple subsets using clustering techniques, we increase the number of explanatory variables and elucidate the role of weather in predicting different ranges of incidence data. Our clustering-integrated regression models, accompanied by optimal barriers, provide insights into the complex relationship between malaria incidence and well-established influencing weather factors such as rainfall and temperature.We explore two models. The first model incorporates lagged incidence and individual-specific effects. The second model focuses solely on weather components. Selection of a model depends on decision-makers priorities. The model one is recommended for higher predictive accuracy. Moreover, our findings reveal significant variability in malaria incidence, specific to certain geographic clusters and beyond what can be explained by observed weather variables alone.Notably, rainfall and temperature exhibit varying marginal effects across incidence clusters, indicating their differential impact on malaria transmission. High rainfall correlates with lower incidence, possibly due to its role in flushing mosquito breeding sites. On the other hand, temperature could not predict high-incidence cases, suggesting that other factors other than temperature contribute to high cases.Our study addresses the demand for comprehensive modeling of malaria incidence, particularly in regions like Nigeria where the disease remains prevalent. By integrating clustering techniques with regression analysis, we offer a nuanced understanding of how predetermined weather factors influence malaria transmission. This approach aids public health authorities in implementing targeted interventions. Our research underscores the importance of considering local contextual factors in malaria control efforts and highlights the potential of weather-based forecasting for proactive disease management.
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  • 文章类型: Journal Article
    污染是全球环境变化的一个组成部分,然而,污染和气候对陆地生态系统的综合和相互作用影响仍然没有得到充分理解。本研究旨在探讨污染是否会改变环境空气温度对草食性昆虫种群动态的影响。在1995年至2005年之间,我们研究了两种密切相关的飞蛾的种群,Eriocraniasempurella和E.sangii,在距离Monchegorsk一家大型铜镍冶炼厂1至64公里的八个地点,俄罗斯。我们发现污染和温度会影响山桦树叶片中Eriocrania幼虫的开采性能,异形的白桦。普米拉,通过多种途径。从幼虫和Fras重量的不一致变化中可以明显看出这一点,雷区,和叶子的大小。我们发现,在空间和时间尺度上,随着污染水平的降低,叶片质量和幼虫重量都会增加,并将其归因于二氧化硫的影响,而不是微量元素(镍和铜)。桦树叶的质量随着春季(5月)温度的升高而增加,使Eriocrania幼虫获得更大的重量,同时消耗更少的生物量。在幼虫生长期(6月初至7月初),Eriocrania幼虫的消费量随着温度的升高而增加,大概是为了弥补增加的代谢费用。与我们的期望相反,人均种群变化率与幼虫体重无关,也不随污染梯度变化。然而,我们发现了污染和气候对人口变化率的交互影响。在轻度污染和未污染的地点,随着冬季温度的升高,这一比率下降,但在重度污染的地点保持不变。我们得出的结论是,污染破坏了调节Eriocrania蛾的自然种群动态的机制。
    Pollution is an integral part of global environmental change, yet the combined and interactive effects of pollution and climate on terrestrial ecosystems remain inadequately understood. This study aims to explore whether pollution alters the impacts of ambient air temperature on the population dynamics of herbivorous insects. Between 1995 and 2005, we studied populations of two closely related moths, Eriocrania semipurpurella and E. sangii, at eight sites located 1 to 64 km from a large copper‑nickel smelter in Monchegorsk, Russia. We found that pollution and temperature influence the performance of Eriocrania larvae mining in the leaves of mountain birch, Betula pubescens var. pumila, through multiple pathways. This is evident from the unconsistent changes observed in larval and frass weight, mine area, and leaf size. We found increases in both leaf quality and larval weight with decreasing pollution levels at both spatial and temporal scales and attributed these to the impact of sulphur dioxide, rather than trace elements (nickel and copper). The quality of birch leaves increased with spring (May) temperatures, enabling Eriocrania larvae to achieve greater weight while consuming less biomass. During the larval growth period (early June to early July), Eriocrania larvae increased their consumption with rising temperatures, presumably to compensate for increased metabolic expenses. Contrary to our expectations, the per capita rate of population change did not correlate with larval weight and did not vary along the pollution gradient. Nevertheless, we detected interactive effects of pollution and climate on the rate of population change. This rate decreased with rising winter temperatures in slightly polluted and unpolluted sites but remained unchanged in heavily polluted sites. We conclude that pollution disrupts mechanisms regulating the natural population dynamics of Eriocrania moths.
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  • 文章类型: Journal Article
    霉菌毒素污染在发展中国家是一个重大问题,特别是在巴基斯坦北部的气候波动。这项研究旨在评估上地尔(干温带)和上斯瓦特(潮湿温带)地区的药用和调味品植物中的黄曲霉毒素污染。收集植物样品并筛选霉菌毒素(黄曲霉毒素-B1和黄曲霉毒素-B-2)。结果显示,与AFB-2(846±241.56)相比,AFB-1(11,505.42±188.82)水平较高。AFB-1在科里安菜中的最大污染(1154.5±13.43ng至3328±9.9ng),其次是F.vulgare(883±9.89ng至2483±8.4ng),T.ammi(815±11.31ng至2316±7.1ng),和C.longa(935.5±2.12ng至2009±4.2ng),而在C.cyminum中报告了最小值(671±9.91ng至1995±5.7ng)。抗真菌测试表明某些植物物种具有潜在的抗性(C.cyminum),而A.flavus是毒素贡献最多的物种,由于高抗性低于80%(54.2±0.55至79.5±2.02)。HPLC分析显示,羟基苯甲酸(5136amu)是主要的平均植物化学物质,其次是间苯三酚(4144.31amu),分别来自C。平均植物化学物质的比较揭示了C.cyminum(2885.95)中的最大浓度,其次是C.longa(1892.73)。研究结果表明,平均真菌毒素和植物化学浓度之间存在统计学上显着的强负相关(y=-2.7239×5141.9;r=-0.8136;p<0.05)。温度与黄曲霉毒素水平呈正相关(p<0.01),而湿度的相关性较弱。海拔呈负相关(p<0.05),而地理因素(纬度和经度)具有混合相关性(p<0.05)。由于气候和地理因素,特定地区表现出黄曲霉毒素增加的趋势。
    Mycotoxin contamination poses a significant problem in developing countries, particularly in northern Pakistan\'s fluctuating climate. This study aimed to assess aflatoxin contamination in medicinal and condiment plants in Upper Dir (dry-temperate) and Upper Swat (moist-temperate) districts. Plant samples were collected and screened for mycotoxins (Aflatoxin-B1 and Aflatoxin-B-2). Results showed high levels of AFB-1 (11,505.42 ± 188.82) as compared to AFB-2 (846 ± 241.56). The maximum contamination of AFB-1 in Coriandrum sativum (1154.5 ± 13.43 ng to 3328 ± 9.9 ng) followed by F. vulgare (883 ± 9.89 ng to 2483 ± 8.4 ng), T. ammi (815 ± 11.31 ng to 2316 ± 7.1 ng), and C. longa (935.5 ± 2.12 ng to 2009 ± 4.2 ng) while the minimum was reported in C. cyminum (671 ± 9.91 ng to 1995 ± 5.7 ng). Antifungal tests indicated potential resistance in certain plant species (C. cyminum) while A. flavus as the most toxins contributing species due to high resistance below 80% (54.2 ± 0.55 to 79.5 ± 2.02). HPLC analysis revealed hydroxyl benzoic acid (5136 amu) as the dominant average phytochemical followed by phloroglucinol (4144.31 amu) with individual contribution of 8542.08 amu and 12,181.5 amu from C. cyaminum. The comparison of average phytochemicals revealed the maximum concentration in C. cyminum (2885.95) followed by C. longa (1892.73). The findings revealed a statistically significant and robust negative correlation (y = - 2.7239 ×  + 5141.9; r = - 0.8136; p < 0.05) between average mycotoxins and phytochemical concentrations. Temperature positively correlated with aflatoxin levels (p < 0.01), while humidity had a weaker correlation. Elevation showed a negative correlation (p < 0.05), while geographical factors (latitude and longitude) had mixed correlations (p < 0.05). Specific regions exhibited increasing aflatoxin trends due to climatic and geographic factors.
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  • 文章类型: Journal Article
    在所有主要的脊椎动物谱系中都有人工进化,并且通常与形态适应和增加的多样化相关,同时伴随着进入新的生态位空间。在鳞片爬行动物中,脚,爪子,和尾巴形态是经过充分研究的适应,被证明与向人工现实的过渡有关。这里,我们研究了一个不太容易理解的特征——龙骨尺度——与微生境的关系,气候,以及跨不同蜥蜴辐射的多样化动态,阿伽玛科.我们发现祖先的加甲虫背部有龙骨,但腹侧没有。进一步,背龙骨和腹龙骨在进化上解耦。腹侧龙骨鳞片与人造物体一起反复演变,可能有利于减少磨损或在攀爬时促进互锁。我们没有发现龙骨秤和多样化之间的联系,表明龙骨不允许在其他树栖相关性状中观察到更精细的微生境划分。我们还发现了龙骨腹侧鳞片与陆地物种降水之间的关系,我们认为龙骨可能起到减少鳞片降解的作用。我们的结果表明,龙骨腹侧鳞片促进了跨agamid蜥蜴向树体的过渡,并强调需要进行未来的研究,以探索其与微生境和气候相关的生物力学功能。
    Arboreality has evolved in all major vertebrate lineages and is often associated with morphological adaptations and increased diversification concomitant with accessing novel niche space. In squamate reptiles, foot, claw, and tail morphology are well-studied adaptations shown to be associated with transitions to arboreality. Here, we examined a less well understood trait-the keeled scale-in relation to microhabitat, climate, and diversification dynamics across a diverse lizard radiation, Agamidae. We found that the ancestral agamid had keeled dorsal but not ventral scales; further, dorsal and ventral keels are evolutionarily decoupled. Ventral keeled scales evolved repeatedly in association with arboreality and may be advantageous in reducing wear or by promoting interlocking when climbing. We did not find an association between keeled scales and diversification, suggesting keels do not allow finer-scale microhabitat partitioning observed in other arboreal-associated traits. We additionally found a relationship between keeled ventral scales and precipitation in terrestrial species where we posit that the keels may function to reduce scale degradation. Our results suggest that keeled ventral scales facilitated transitions to arboreality across agamid lizards, and highlight a need for future studies that explore their biomechanical function in relation to microhabitat and climate.
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  • 文章类型: Journal Article
    尽管预计气候变化将推动树种向较冷和较湿润的分布区域发展,缺乏广泛的经验证据。一种可能性是森林中过去和现在的人类活动掩盖或改变了气候的影响。这里,使用来自73个分布广泛的物种的200多万棵监测树木的数据,我们量化了北半球森林气候生态位内树种密度的变化。我们观察到不同物种的平均密度降低,再加上树木大小的增加趋势。然而,密度变化的方向和幅度在物种之间表现出相当大的变异性,受先前林分水平扰动导致的林分发展的影响。值得注意的是,在考虑展台发展时,我们的发现表明,43%的物种在寒冷和潮湿的气候条件下密度发生了显著变化,相比之下,在早期和后期发展的林分中,只有14%的物种将其密度显着改变为温暖和干旱的条件。观测到的气候驱动密度变化与耐旱性相关的物种性状没有明显关联,招募和分散能力,或资源使用,也不考虑物种的温度或干旱程度,留下的潜在机制不确定。森林保护政策和相关的管理策略可能要考虑预期的长期物种范围变化以及当代分布内密度变化的整合。
    Although climate change is expected to drive tree species toward colder and wetter regions of their distribution, broadscale empirical evidence is lacking. One possibility is that past and present human activities in forests obscure or alter the effects of climate. Here, using data from more than two million monitored trees from 73 widely distributed species, we quantify changes in tree species density within their climatic niches across Northern Hemisphere forests. We observe a reduction in mean density across species, coupled with a tendency toward increasing tree size. However, the direction and magnitude of changes in density exhibit considerable variability between species, influenced by stand development that results from previous stand-level disturbances. Remarkably, when accounting for stand development, our findings show a significant change in density toward cold and wet climatic conditions for 43% of the species, compared to only 14% of species significantly changing their density toward warm and arid conditions in both early- and late-development stands. The observed changes in climate-driven density showed no clear association with species traits related to drought tolerance, recruitment and dispersal capacity, or resource use, nor with the temperature or aridity affiliation of the species, leaving the underlying mechanism uncertain. Forest conservation policies and associated management strategies might want to consider anticipated long-term species range shifts alongside the integration of contemporary within-distribution density changes.
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  • 文章类型: Journal Article
    确保粮食安全和可持续资源管理已成为全球首要关切,促使人们高度重视土地适宜性分析,以提高农业生产。在这项研究中,采用AHP加权叠加法划分了桂林水稻种植适宜性,伊朗,水稻生产的中央枢纽。十六种气候,地形,和土壤变量进行了整合,并对各个地图进行了重新分类,以符合水稻生产的具体要求。结果显示了三个适合性类别:包括\'非常适合,\'\'合适,\'和\'适度合适\',占91%,6%,还有3%的土地,分别。土壤属性,特别是有机物,显著影响适用性(重量值为0.745),在评估中,地形和土壤因素超过了气候。虽然盐度通常不存在,有机质缺乏影响44%的土地。磷失衡很普遍,观察到10%的钾毒性。微量元素缺乏,尤其是铁和锌,被注意到。此外,结果表明,在评估研究区域内水稻种植土地适宜性方面,地形和土壤属性比气候相关因素起着更重要的作用。本研究对研究区域的所有变量进行了全面的空间分析,阐明水稻种植土地适宜性的复杂性。这些发现有助于理解粮食安全背景下的农业可持续性和资源管理战略。
    Ensuring food security and sustainable resource management has become a paramount global concern, prompting significant attention to land suitability analysis for enhancing agricultural production. In this study, an AHP-weighted overlay method was employed to delineate rice cultivation suitability in Guilan province, Iran, a central hub for rice production. Sixteen climatic, topographic, and soil variables were integrated, and individual maps were reclassified to align with the specific requisites for rice production. The results revealed three suitability classes: including \'very suitable,\' \'suitable,\' and \'moderately suitable\', covering 91%, 6%, and 3% of the land, respectively. Soil attributes, particularly organic matter, significantly influenced suitability (weight value of 0.745), with topographic and soil factors outweighing climate in assessment. While salinity is generally absent, organic matter deficiency affects 44% of the land. Phosphorus imbalances are prevalent, with potassium toxicity observed in 10%. Microelement deficiencies, especially in iron and zinc, are noted. Additionally, the results indicated that topographic and soil attributes played a more significant role than climate-related factors in assessing land suitability for rice cultivation within the study area. This research provides a comprehensive spatial analysis of all variables in the study region, shedding light on the complexities of land suitability for rice cultivation. These findings contribute to the understanding of agricultural sustainability and resource management strategies in the context of food security.
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  • 文章类型: Journal Article
    植物-传粉者相互作用的多样性植根于花卉资源,花蜜被认为是传粉者生产的主要花卉奖励植物之一。然而,对动物授粉花蜜产生的被子植物的数量及其在世界范围内的分布的全球评估仍然难以捉摸。我们编制了一个完整的数据库,包含322个家庭的7621种植物,以估计依赖动物授粉的产花蜜被子植物的数量和比例。通过对植物群落的广泛采样,我们还探索了花蜜生产之间的相互作用,花卉资源多样性,纬度和海拔梯度,当代气候,和环境特征。大约有223308个动物授粉的被子植物产生花蜜,占生物授粉物种的74.4%。产花蜜植物的全球分布格局沿纬度和海拔梯度显示出明显的趋势,在高纬度和海拔地区生产花蜜的植物比例增加。相反,温暖和潮湿气候下的热带群落表现出更大的花卉资源多样性和较低的花蜜生产植物比例。这些发现表明,气候驱动的生态趋势促进了温暖和季节性较少气候下花卉资源的多样化,减少单独生产花蜜的植物的比例。我们的研究为理解植物-传粉者关系提供了基线,植物多样化,以及植物性状的分布。
    The diversity of plant-pollinator interactions is grounded in floral resources, with nectar considered one of the main floral rewards plants produce for pollinators. However, a global evaluation of the number of animal-pollinated nectar-producing angiosperms and their distribution world-wide remains elusive. We compiled a thorough database encompassing 7621 plant species from 322 families to estimate the number and proportion of nectar-producing angiosperms reliant on animal pollination. Through extensive sampling of plant communities, we also explored the interplay between nectar production, floral resource diversity, latitudinal and elevational gradients, contemporary climate, and environmental characteristics. Roughly 223 308 animal-pollinated angiosperms are nectar-producing, accounting for 74.4% of biotic-pollinated species. Global distribution patterns of nectar-producing plants reveal a distinct trend along latitudinal and altitudinal gradients, with increased proportions of plants producing nectar in high latitudes and altitudes. Conversely, tropical communities in warm and moist climates exhibit greater floral resource diversity and a lower proportion of nectar-producing plants. These findings suggest that ecological trends driven by climate have fostered the diversification of floral resources in warmer and less seasonal climates, reducing the proportion of solely nectar-producing plants. Our study provides a baseline for understanding plant-pollinator relationships, plant diversification, and the distribution of plant traits.
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