elevation

高程
  • 文章类型: Journal Article
    全球变化正在影响全球植物物种的分布和种群动态,导致分布向两极和更高海拔方向转移等趋势。然而,我们很难理解为什么单个物种对变暖和其他环境变化的反应不同,或者社区的特征组成如何反应。在这里,我们提出了两个关于魁北克温带山地森林42年全球变化中植物物种和群落变化的问题,加拿大:(1)性状构成如何,阿尔法多样性,和林下维管植物群落的β多样性在1970年至2010年之间发生变化,在此期间该地区经历了1.5°C的变暖和氮沉积的变化?(2)性状可以预测该时间段内物种海拔和丰度的变化吗?对于46个林下维管物种,我们在当地测量了六个地上性状,其中36种(不包括灌木),我们还测量了五个地下性状。总的来说,它们捕获了与气候和资源生态位相关的表型变异的主要维度。在社区层面,高海拔地块的性状组成发生了变化,主要表现为两个根系性状:特定根长减少,生根深度增加。高海拔地块的平均特征值随时间向最初与低海拔地块相关的值移动。这些变化导致了跨海拔的性状均质化。性状的社区级变化反映了该地点其他地方报道的分类学变化。在物种层面,预测物种高度和丰度变化的三个性状中的两个是地下性状(低菌根分数和浅生根)。这些发现强调了根系性状的重要性,which,随着叶的质量分数,与四十年来分布和丰度的变化有关。在海拔和时间梯度上,社区水平的性状变化在很大程度上相似。相比之下,通常与群落水平的低海拔相关的性状并不能预测物种之间在丰度或分布变化方面的差异,表明物种和社区层面的反应之间存在脱钩。总的来说,变化与气候变暖和氮利用率增加的一些影响是一致的。
    Global change is affecting the distribution and population dynamics of plant species across the planet, leading to trends such as shifts in distribution toward the poles and to higher elevations. Yet, we poorly understand why individual species respond differently to warming and other environmental changes, or how the trait composition of communities responds. Here we ask two questions regarding plant species and community changes over 42 years of global change in a temperate montane forest in Québec, Canada: (1) How did the trait composition, alpha diversity, and beta diversity of understory vascular plant communities change between 1970 and 2010, a period over which the region experienced 1.5°C of warming and changes in nitrogen deposition? (2) Can traits predict shifts in species elevation and abundance over this time period? For 46 understory vascular species, we locally measured six aboveground traits, and for 36 of those (not including shrubs), we also measured five belowground traits. Collectively, they capture leading dimensions of phenotypic variation that are associated with climatic and resource niches. At the community level, the trait composition of high-elevation plots shifted, primarily for two root traits: specific root length decreased and rooting depth increased. The mean trait values of high-elevation plots shifted over time toward values initially associated with low-elevation plots. These changes led to trait homogenization across elevations. The community-level shifts in traits mirrored the taxonomic shifts reported elsewhere for this site. At the species level, two of the three traits predicting changes in species elevation and abundance were belowground traits (low mycorrhizal fraction and shallow rooting). These findings highlight the importance of root traits, which, along with leaf mass fraction, were associated with shifts in distribution and abundance over four decades. Community-level trait changes were largely similar across the elevational and temporal gradients. In contrast, traits typically associated with lower elevations at the community level did not predict differences among species in their shift in abundance or distribution, indicating a decoupling between species- and community-level responses. Overall, changes were consistent with some influence of both climate warming and increased nitrogen availability.
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  • 文章类型: Journal Article
    气候变化可能会影响外热的生存和繁殖。蟾蜍头蜥蜴,它具有在地球上所有爬行动物物种中海拔最高的区别,海拔范围从3600到5000米,代表了研究跨海拔梯度对气候变化的适应的理想模型。这里,我们使用了机械和杂种分布模型(HSDM)以及热生物学的特征测量(CTmax,CTmin,和Tsel)来模拟和比较蜥蜴响应气候变化的跨海拔分布和活动时期。仅使用气候因素的NicheMapR模拟预测,由于分布减少,所有人口将受到气候变化(3°C)的负面影响。然而,在考虑热生理特性的模拟中,影响明显减少。在气候变化期间,预测所有人口的活动时间更长。预测合适的分布会略有变化,预计高海拔和低海拔人口都会增加。然而,预测表明,与较低海拔(<4200m)的种群相比,较高海拔(>4200m)的种群的合适栖息地增加更为明显。这项研究强调了气候变化对种群建立的关键影响,并强调了生理特征在分布模拟中的重要性,以供未来研究了解动物适应极端高环境的潜在制约因素。
    Climate change may affect the survival and reproduction of ectotherms. The toad-headed lizard Phrynocephalus theobaldi, which holds the distinction of occupying the highest elevation among all reptile species on Earth, with an elevational range from 3600 to 5000 m, represents an ideal model for studying the adaptations to climatic changes across elevational gradients. Here, we used mechanistic and hybrid species distribution models (HSDM) together with characteristic measurements of thermal biology (CTmax, CTmin, and Tsel) to simulate and compare the distribution and activity periods of the lizard across elevations in response to climate change. NicheMapR simulations using only climate factors predicted that all populations will be negatively impacted by climate change (+3°C) by suffering a reduced distribution. However, the impact was clearly reduced in simulations that accounted for thermal physiological traits. Longer activity periods were predicted for all populations during climate change. The suitable distribution is predicted to change slightly, with an increase anticipated for both high and low elevation populations. However, the forecast indicates a more pronounced increase in suitable habitats for populations at higher elevations (>4200 m) compared to those at lower elevations (<4200 m). This study underscores the key influence of climate change on population establishment and stresses the importance of physiological traits in distribution simulation for future studies to understand the potential constraints in animal adaptation to extreme high environments.
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  • 文章类型: Journal Article
    探索沿海拔梯度的物种多样性对于理解潜在机制很重要。我们的研究重点是分析朝鲜半岛三个高山上不同营养和分类水平的真菌群落及其亚群落的物种多样性,每个都位于不同的气候带。采用高通量测序,我们旨在评估真菌多样性模式,并调查影响真菌多样性的主要环境因素。我们的结果表明,土壤真菌多样性在不同的山区表现出不同的海拔分布模式,强调气候的综合影响,土壤性质,和地理拓扑。值得注意的是,土壤中的总磷含量和有效磷含量是解释归因于土壤特性的多样性差异的关键决定因素。尽管真菌多样性对不同营养行会和分类水平之间的海拔梯度的反应各不相同,他们的主要环境决定因素仍然非常一致。特别是,总磷和有效磷含量与大多数营养行会的多样性和分类水平显着相关。我们的研究表明,沿海拔梯度缺乏统一的多样性模式,强调真菌对土壤条件的一般敏感性。通过丰富我们对真菌多样性动态的理解,这项研究增强了我们对海拔真菌多样性的形成和维持以及山区生态系统中微生物群落对气候变化的响应的理解。这项研究为未来类似生物群落的生态学研究提供了有价值的见解。
    Exploring species diversity along elevational gradients is important for understanding the underlying mechanisms. Our study focused on analyzing the species diversity of fungal communities and their subcommunities at different trophic and taxonomic levels across three high mountains of the Korean Peninsula, each situated in a different climatic zone. Using high-throughput sequencing, we aimed to assess fungal diversity patterns and investigate the primary environmental factors influencing fungal diversity. Our results indicate that soil fungal diversity exhibits different elevational distribution patterns on different mountains, highlighting the combined effects of climate, soil properties, and geographic topology. Notably, the total and available phosphorus contents in the soil emerged as key determinants in explaining the differences in diversity attributed to soil properties. Despite the varied responses of fungal diversity to elevational gradients among different trophic guilds and taxonomic levels, their primary environmental determinants remained remarkably consistent. In particular, total and available phosphorus contents showed significant correlations with the diversity of the majority of the trophic guilds and taxonomic levels. Our study reveals the absence of a uniform diversity pattern along elevational gradients, underscoring the general sensitivity of fungi to soil conditions. By enriching our understanding of fungal diversity dynamics, this research enhances our comprehension of the formation and maintenance of elevational fungal diversity and the response of microbial communities in mountain ecosystems to climate change. This study provides valuable insights for future ecological studies of similar biotic communities.
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  • 文章类型: Journal Article
    土壤真菌群落在维持高山森林土壤生态系统的生态功能中起着至关重要的作用。然而,目前尚不清楚高山森林不同土壤层中真菌群落的分布格局将如何沿海拔梯度变化。
    因此,IlluminaMiSeq测序技术用于研究Sygera山脉沿海拔梯度(3500m至4300m)的三个土壤层(0-10、10-20和20-30cm)中的真菌群落,位于八一区,林芝市,西藏。
    结果表明:1)土壤深度对真菌多样性的影响大于海拔,表明随着土壤深度的增加,真菌多样性显着降低,但在所有土壤层中,海拔变化均无显着差异。在0-10厘米的土壤层内,担子菌和子囊菌共同主导着微生物群落。然而,随着土壤深度增加到10-20和20-30厘米的土壤层,担子菌主要占主导地位。2)确定过程在0-10cm真菌群落的组装机制中占主导地位,并且随着海拔的增加而保持不变。相比之下,随着海拔的增加,10-20和20-30厘米真菌群落的组装机制从确定性过程转变为随机过程。3)0-10厘米真菌群落的网络复杂度随着海拔的升高而逐渐增加,而10-20和20-30cm真菌群落表现出减少的趋势。与0-10厘米的土层相比,在10-20和20-30厘米的土壤层中,真菌生物标志物的相对丰度发生了更多的变化,表明这些深度的真菌群落对气候变化更敏感。在推动这些改变的关键因素中,土壤温度和湿度土壤水分含量在塑造真菌群落的组装机制和网络复杂性方面至关重要。这项研究有助于理解高寒生态系统中土壤真菌群落格局和沿海拔梯度的驱动因素,并为预测高寒森林中土壤微生物生态系统的功能响应提供了重要的科学依据。
    UNASSIGNED: Soil fungal communities play a crucial role in maintaining the ecological functions of alpine forest soil ecosystems. However, it is currently unclear how the distribution patterns of fungal communities in different soil layers of alpine forests will change along the elevational gradients.
    UNASSIGNED: Therefore, Illumina MiSeq sequencing technology was employed to investigate fungal communities in three soil layers (0-10, 10-20, and 20-30 cm) along an elevational gradient (3500 m to 4300 m) at Sygera Mountains, located in Bayi District, Nyingchi City, Tibet.
    UNASSIGNED: The results indicated that: 1) Soil depth had a greater impact on fungal diversity than elevation, demonstrating a significant reduction in fungal diversity with increased soil depth but showing no significant difference with elevation changes in all soil layers. Within the 0-10 cm soil layer, both Basidiomycota and Ascomycota co-dominate the microbial community. However, as the soil depth increases to 10-20 and 20-30 cm soil layers, the Basidiomycota predominantly dominates. 2) Deterministic processes were dominant in the assembly mechanism of the 0-10 cm fungal community and remained unchanged with increasing elevation. By contrast, the assembly mechanisms of the 10-20 and 20-30 cm fungal communities shifted from deterministic to stochastic processes as elevation increased. 3) The network complexity of the 0-10 cm fungal community gradually increased with elevation, while that of the 10-20 and 20-30 cm fungal communities exhibited a decreasing trend. Compared to the 0-10 cm soil layer, more changes in the relative abundance of fungal biomarkers occurred in the 10-20 and 20-30 cm soil layers, indicating that the fungal communities at these depths are more sensitive to climate changes. Among the key factors driving these alterations, soil temperature and moisture soil water content stood out as pivotal in shaping the assembly mechanisms and network complexity of fungal communities. This study contributes to the understanding of soil fungal community patterns and drivers along elevational gradients in alpine ecosystems and provides important scientific evidence for predicting the functional responses of soil microbial ecosystems in alpine forests.
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  • 文章类型: Journal Article
    特定叶面积(SLA)和叶片干物质含量(LDMC)是关键的叶片功能性状,通常用于反映植物资源利用策略和预测植物对环境变化的响应。总的来说,不同海拔的草地植物表现出不同的生存策略。然而,目前尚不清楚草地植物如何适应海拔变化及其驱动因素。为了解决这个问题,我们利用来自中国不同海拔223个研究地点的草地植物的SLA和LDMC数据,以及气候和土壤数据,采用线性混合效应模型研究草地植物沿不同海拔梯度的资源利用策略及其主要影响因素的变化,方差划分法,分段结构方程建模,等。结果表明,随着高程的增加,SLA显著降低,LDMC显著增加(P<0.001)。这表明跨海拔梯度的草地植物的资源利用策略不同,从较低海拔的“更快的投资回报”过渡到较高海拔的“较慢的投资回报”。跨越不同的高程坡度,气候因子是影响草地植物资源利用策略的主要因素,与土壤养分因子也起着不可忽视的协调作用。其中,年平均降水量和最热月份平均气温是影响草地植物SLA的关键气候因子,解释了28.94%和23.88%的SLA变化,分别。影响草地植物LDMC的主要因素是最热月平均温度和土壤磷含量,相对重要性为24.24%和20.27%,分别。此外,海拔对草地植物资源利用策略的直接影响大于其间接影响(通过影响气候和土壤养分因素)。这些发现强调了海拔对草地植物资源利用策略的实质性影响,对全球变化下的草地管理和保护具有重要的生态价值。
    Specific leaf area (SLA) and leaf dry matter content (LDMC) are key leaf functional traits often used to reflect plant resource utilization strategies and predict plant responses to environmental changes. In general, grassland plants at different elevations exhibit varying survival strategies. However, it remains unclear how grassland plants adapt to changes in elevation and their driving factors. To address this issue, we utilized SLA and LDMC data of grassland plants from 223 study sites at different elevations in China, along with climate and soil data, to investigate variations in resource utilization strategies of grassland plants along different elevational gradients and their dominant influencing factors employing linear mixed-effects models, variance partitioning method, piecewise Structural Equation Modeling, etc. The results show that with increasing elevation, SLA significantly decreases, and LDMC significantly increases (P < 0.001). This indicates different resource utilization strategies of grassland plants across elevation gradients, transitioning from a \"faster investment-return\" at lower elevations to a \"slower investment-return\" at higher elevations. Across different elevation gradients, climatic factors are the main factors affecting grassland plant resource utilization strategies, with soil nutrient factors also playing a non-negligible coordinating role. Among these, mean annual precipitation and hottest month mean temperature are key climatic factors influencing SLA of grassland plants, explaining 28.94% and 23.88% of SLA variation, respectively. The key factors affecting LDMC of grassland plants are mainly hottest month mean temperature and soil phosphorus content, with relative importance of 24.24% and 20.27%, respectively. Additionally, the direct effect of elevation on grassland plant resource utilization strategies is greater than its indirect effect (through influencing climatic and soil nutrient factors). These findings emphasize the substantive impact of elevation on grassland plant resource utilization strategies and have important ecological value for grassland management and protection under global change.
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  • 文章类型: Journal Article
    背景:杜鹃花是一种天然灌木,分布在毕节喀斯特地区的不同海拔,中国,这在防止该地区土地退化方面具有重要作用。在这项研究中,测定了土壤矿质元素含量和土壤酶活性。在三个海拔(1448m,1643米,和1821米)通过高通量测序进行分析,以及土壤细菌群落之间的相互关系,矿物元素,并测定了酶活性。
    结果:土壤细菌群落的香农指数随海拔的增加先升高后降低,在1643m处最高。在1821m处更多的正相关表明种内合作更强。酸杆菌,在所有三个升高处,放线菌和变形菌都是优势门。Mantel检验和相关性分析表明,Fe和土壤脲酶对1448m处的细菌群落有显著影响;有趣的是,在1448m处,氯氟菌与土壤脲酶呈正相关,1821m放线菌与镍和锌呈正相关。铁和土壤脲酶显著影响低海拔的细菌群落,高海拔(1821米)增强了土壤细菌的正相互作用,这可能是R.delavayi适应高海拔环境的策略。
    结论:海拔通过影响土壤矿质元素含量和土壤酶活性,显著影响土壤细菌群落组成。
    BACKGROUND: Rhododendron delavayi is a natural shrub that is distributed at different elevations in the karst region of Bijie, China, and that has an important role in preventing land degradation in this region. In this study, we determined the soil mineral element contents and soil enzyme activities. The composition of the soil bacterial community of R. delavayi at three elevations (1448 m, 1643 m, and 1821 m) was analyzed by high-throughput sequencing, and the interrelationships among the soil bacterial communities, mineral elements, and enzyme activities were determined.
    RESULTS: The Shannon index of the soil bacterial community increased and then decreased with increasing elevation and was highest at 1643 m. Elevations increased the number of total nodes and edges of the soil bacterial community network, and more positive correlations at 1821 m suggested stronger intraspecific cooperation. Acidobacteria, Actinobacteria and Proteobacteria were the dominant phyla at all three elevations. The Mantel test and correlation analysis showed that Fe and soil urease significantly affected bacterial communities at 1448 m; interestingly, Chloroflexi was positively related to soil urease at 1448 m, and Actinobacteria was positively correlated with Ni and Zn at 1821 m. Fe and soil urease significantly influenced the bacterial communities at lower elevations, and high elevation (1821 m) enhanced the positive interactions of the soil bacteria, which might be a strategy for R. delavayi to adapt to high elevation environments.
    CONCLUSIONS: Elevation significantly influenced the composition of soil bacterial communities by affecting the content of soil mineral elements and soil enzyme activity.
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  • 文章类型: Journal Article
    目的:描述和评估用于去除保留的晶状体材料(RLM)的新型平坦部玻璃体切除术(PPV)技术的可行性,这消除了对20号玻璃体内碎裂或全氟化碳辅助抬高的需要。
    方法:介入病例系列。经过彻底的23号PPV,使用抽吸将硬晶状体材料接合并保持粘附在玻璃体切割器上,然后上升到前房。在那里,标准的超声乳化探头,通过角膜切口插入,用于分割和移除材料。
    结果:对3例患者的3只眼进行了手术。在所有的眼睛,RLM可以完全删除。术后,3只眼睛中有2只(67%)达到了20/20的最佳矫正视力。无青光眼等并发症,黄斑囊样水肿,角膜水肿,或记录视网膜脱离。术中,在3只眼中的2只(67%)中检测到视网膜撕裂,并接受了眼内激光视网膜固定术和气液交换治疗。一只眼睛随后出现黄斑裂孔,需要进一步手术。
    结论:在PPV期间,抽吸辅助晶状体抬高可能是一种可行且方便的去除RLM的技术。尽管与其他方法的比较超出了本初步研究的范围,视觉结局和并发症发生率令人鼓舞,应在更大的患者组中进行验证.
    OBJECTIVE: To describe and evaluate the feasibility of a novel pars plana vitrectomy (PPV) technique for the removal of retained lens material (RLM), which obviates the need for either 20-gauge intravitreal fragmentation or perfluorocarbon-assisted elevation.
    METHODS: Interventional case series. After thorough 23-gauge PPV, the hard lens material is engaged and held adherent to the vitreous cutter using aspiration, then raised into the anterior chamber. There, a standard phacoemulsification probe, inserted through a corneal incision, is used to fragment and remove the material.
    RESULTS: Three eyes of 3 patients were operated on. In all eyes, RLM could be removed completely. Postoperatively, 2 of 3 eyes (67%) achieved 20/20 best-corrected visual acuity. No complications such as glaucoma, cystoid macular edema, corneal edema, or retinal detachments were recorded. Intraoperatively, retinal tears were detected in 2 of 3 (67%) eyes and treated with endolaser retinopexy and fluid-air exchange. One eye subsequently developed macular hole requiring further surgery.
    CONCLUSIONS: Suction-assisted lens elevation may be a viable and convenient technique to remove RLM during PPV. Although the comparison with other methods is beyond the scope of this preliminary study, visual outcomes and complication rates were encouraging and should be validated in a larger group of patients.
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  • 文章类型: Journal Article
    菌根关联是塑造森林群落结构和多种生态系统功能的关键共生关系。然而,我们缺乏一个框架来预测不同菌根关联在整个生态系统多功能性的综合代理中的不同优势。这里,我们使用了包含菌根关联多样性和18个与支持相关的生态系统过程的数据集,供应,和调节服务,以研究外生菌根(EcM)关联的优势如何影响中国西南亚热带山地森林中的生态系统多功能性。同时,我们综合了EcM显性效应对森林生物群落生态系统功能的影响。我们的结果表明,海拔显着改变了EcM树的分布和真菌优势,这反过来又同时影响了多个功能。多功能随着EcM关联比例的增加而增加,支持外生菌根优势假说。同时,我们观察到EcM优势对个体生态系统功能的影响在森林生物群落之间表现出不同的关系。我们的发现强调了外生菌根优势在调节亚热带森林多功能性方面的重要性。然而,塑造生态系统功能的这种外生菌根反馈不一定在森林中推广。因此,我们认为,响应菌根组成变化的生态系统多功能性的预测可能会在空间和时间上有所不同。
    Mycorrhizal associations are key mutualisms that shape the structure of forest communities and multiple ecosystem functions. However, we lack a framework for predicting the varying dominance of distinct mycorrhizal associations in an integrated proxy of multifunctionality across ecosystems. Here, we used the datasets containing diversity of mycorrhizal associations and 18 ecosystem processes related to supporting, provisioning, and regulating services to examine how the dominance of ectomycorrhiza (EcM) associations affects ecosystem multifunctionality in subtropical mountain forests in Southwest China. Meanwhile, we synthesized the prevalence of EcM-dominant effects on ecosystem functioning in forest biomes. Our results demonstrated that elevation significantly modified the distributions of EcM trees and fungal dominance, which in turn influenced multiple functions simultaneously. Multifunctionality increased with increasing proportion of EcM associations, supporting the ectomycorrhizal-dominance hypothesis. Meanwhile, we observed that the impacts of EcM dominance on individual ecosystem functions exhibited different relationships among forest biomes. Our findings highlight the importance of ectomycorrhizal dominance in regulating multifunctionality in subtropical forests. However, this ectomycorrhizal feedback in shaping ecosystem functions cannot necessarily be generalized across forests. Therefore, we argue that the predictions for ecosystem multifunctionality in response to the shifts of mycorrhizal composition could vary across space and time.
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  • 文章类型: Journal Article
    热带河流生态学的主要数据差距是上游河流自然水净化的文献有限。这项研究使用混合方法(水质评估,工厂库存,现场观测,规范对应分析,社区采访)。结果表明,与污染的距离在河流的自净中起着重要作用,而花卉多样性则使河岸免于进一步污染水并同时吸收空气污染物。一般来说,污染减少和百分比变化在距点源2和3公里处呈指数变化,然后在4和5公里处呈锥形。在离点源3公里处,TDS改善30%,BOD和盐度,25%为EC,TSS中的20%,35%在WQI,36%的CPI,注意到DO为50%。影响河流自净过程的关键因素是距污染源的距离,高程,人为干扰(由%树冠表示)和温度。这些发现强调了远离污染源和花卉多样性在推动水质改善方面的重要性,对热带地区可持续水资源管理的影响。
    这项研究记录了受环境因素和大型植物多样性影响的巴利河下游水质的改善,这是对热带河流生态学主要数据差距的贡献,该差距目前在上游河流的自然水净化方面的文献有限。该研究还显示了水质的马赛克相互作用,植物多样性,远离污染,人为干扰,和研究不足的热带河流的空气质量。Further,这项研究在记录Balili河下游方面是独一无二的,因为以前的大多数研究都集中在河的上游部分。
    A major data gap in tropical river ecology is the limited documentation of natural water purification of upstream rivers. This study documented the improvement of water quality of downstream Balili River as affected by environmental factors and macrophyte diversity using a mixed-method approach (water quality assessment, plant inventory, field observation, canonical correspondence analysis, community interview). Results showed that the distance from pollution plays a significant role in the self-purification of the river while the floral diversity maintains the riparian from further contaminating the water and at the same time absorbing air pollutants. Generally, the pollution reduction and %change is exponential at 2 and 3 km from point source then taper at 4 and 5 km. At 3 km from the point source, 30% improvement in TDS, BOD and salinity, 25% for EC, 20% in TSS, 35% in WQI, 36% in CPI, and 50% for DO were noted. Key factors that influence the self-purification process in the river were distance from pollution source, elevation, human disturbance (as indicated by %tree canopy) and temperature. These findings highlight the importance of distance from pollution sources and floral diversity in driving water quality improvements, with implications for sustainable water resource management in tropical regions.
    This study documented the improvement of water quality of downstream Balili River as affected by environmental factors and macrophyte diversity – as contribution to the major data gap in tropical river ecology which currently has limited documentation on natural water purification of upstream rivers. The study also shows the mosaic interplay of water quality, plant diversity, distance from pollution, human disturbance, and air quality in understudied tropical river. Further, this study is unique in documenting the downstream of Balili River since majority of the previous studies were concentrated in the upstream portion of the river.
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  • 文章类型: Journal Article
    稀土矿物的原位浸出导致阳光和阴凉的斜坡之间的生态差异,这可能与相关土壤基质中稀土元素的分布差异有关。对中国南方稀土元素尾矿的研究表明,与阴暗的斜坡相比,阳光充足的斜坡上稀土元素的总浓度更高。具体来说,可交换稀土元素分数(F1-稀土元素)在阴山斜坡上较高,而在阳光明媚的斜坡上,Fe/Mn氧化物结合的稀土元素分数(F3-稀土元素)较高。此外,低海拔地区轻稀土(LREE)浓度较低。除Ce部分保持稳定外,这表明所有稀土元素分布都发生了变化,从F1-稀土元素向残余部分移动。分层聚类和主成分分析显示,F3-稀土元素之间存在很强的相关性,有机质束缚稀土元素(F4-稀土元素),和LREEs,F3-稀土元素与阳光照射呈正相关。偏最小二乘路径模拟分析表明,OM促进了阳光照射驱动的土壤中LREE向F3和F4-REE的转化。此外,随着Feo/Fed比率的下降,更多的LREE转换为F3。这项研究表明,阳光和海拔都在原位尾矿中稀土元素的地球化学动力学中起着至关重要的作用。倡导进行环境评估,以准确了解稀土开采的生态影响。
    The in-situ leaching of rare earth minerals results in ecological differences between sunlit and shady slopes, which may be related to differences in the distribution REEs in the associated soil matrices. Studies of REEs mine tailings in Southern China indicated higher total concentrations of REEs on sunlit slopes compared to shady ones. Specifically, the exchangeable REEs fraction (F1-REEs) was higher on the shady slopes, whereas the Fe/Mn oxides bound REEs fraction (F3-REEs) was higher on the sunlit slopes. In addition, light REE (LREE) concentrations were lower at lower elevations. With the exception of the Ce fraction which remained stable, this indicated a change in all REEs distributions, moving from F1-REEs towards the residual fraction. Hierarchical cluster and principal component analysis revealed a strong correlation between F3-REEs, organic matter bound REEs (F4-REEs), and LREEs, and a positive association of F3-REEs with sunlight exposure. Partial Least Squares Path Modeling analysis suggested that OM promoted the conversion of LREEs to F3 and F4-REEs in soil driven by sunlight exposure. Additionally, as the Feo/Fed ratio decreased, more LREEs were converted to F3. This study suggests that sunlight and elevation both play a critical role in the geochemical dynamics of REEs in in-situ tailings, advocating for environmental evaluations to be undertaken in order to accurately understand the ecological impacts of rare earth mining.
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