Aquatic Botany最新文献

Within-lake isolation and reproductive strategy of Stuckenia pectinata (L.) Börner at Lake Naivasha (Kenya): About water level fluctuations and alien species pectinata （L.）菌的湖内隔离与繁殖策略Börner奈瓦沙湖（肯尼亚）：关于水位波动和外来物种

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-11-27 DOI: 10.1016/j.aquabot.2024.103840

Ludwig Triest , Tim Sierens , Josphine Njambuya , Taita Terer , Iris Stiers

Submerged aquatic plants with mixed reproduction mode may show enhanced clonal growth explained by environmental conditions. For Stuckenia pectinata (L.) Börner this has been linked to within-lake factors, both biotic (tuber predation, herbivory, periphyton shading) and abiotic (hydrological connectivity, sediment type). We investigated the S. pectinata population from Lake Naivasha, where submerged aquatic plants tolerated strong historical water level fluctuations until introduced crayfish, shading by floating exotic weeds and increased turbidity nearly eradicated them, although some stands now rebounded in various lake areas. Using 13 nuclear microsatellite loci, we analyzed genetic diversity and structure of S. pectinata subpopulations along the southeastern shoreline of the main lake and inside Crescent Island Crater, a peripheral lake basin enclosed within the rim of an extinct volcano. Results revealed a predominantly sexual reproductive strategy with limited clonal expansion in the main lake contrasting with pronounced clonal growth in the crater basin. Each subpopulation experienced recent bottlenecks. Crater basin subpopulations exhibited the strongest divergence, lower clonal diversity and larger-sized clones. We explain this differentiation by the exposed crater rim acting as barrier, isolating the crater basin from the main lake during recent decades when low water levels prevailed, accompanied with less negative impact from alien species than in the main lake. Clonal extension occurred on steep-sloping hard sandy substrates, that likely prompted local reproductive adaptations. Genetic diversity, clonal structure and connectivity patterns are discussed in the light of the specific history and features of Lake Naivasha.

混合繁殖模式的沉水水生植物克隆生长加快可能与环境条件有关。果胶链球菌（L.）Börner这与湖内因素有关，包括生物因素（块茎捕食、草食、周围植物遮荫）和非生物因素（水文连通性、沉积物类型）。我们调查了来自Naivasha湖的S. pectinata种群，在小龙虾引入之前，该湖的水下水生植物耐受了强烈的历史水位波动，漂浮的外来杂草遮蔽了它们，浊度增加几乎根除了它们，尽管一些林分现在在不同的湖区反弹。利用13个核微卫星位点，分析了主湖东南岸线和月牙岛火山口（一个封闭在死火山边缘的外围湖盆）内的S. pectinata亚群的遗传多样性和结构。结果表明，与火山口盆地克隆生长明显相反，主湖克隆繁殖策略以有性繁殖为主，克隆扩张有限。每个亚种群最近都经历了瓶颈。火山口盆地亚居群分化最强，无性系多样性较低，无性系大小较大。我们解释了这种差异，暴露的火山口边缘作为屏障，在近几十年的低水位期间将火山口盆地与主湖隔离开来，同时外来物种的负面影响比主湖小。克隆扩展发生在陡峭的硬砂基质上，这可能促进了当地的生殖适应。结合奈瓦沙湖的具体历史和特征，讨论了遗传多样性、克隆结构和连通性模式。

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引用次数: 0

Effects of rainwater on the carrageenan yield and quality and dry yield biomass of eucheumatoid seaweed Kappaphycus alvarezii 雨水对拟真金藻卡拉胶产量、品质及干产量生物量的影响

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-11-25 DOI: 10.1016/j.aquabot.2024.103837

Albaris B. Tahiluddin , Rizal Jhunn F. Robles , Mur-hamida S. Eldani-Tahiluddin

Kappaphycus alvarezii, a commercially valuable eucheumatoid seaweed, is widely cultivated in equatorial regions for its kappa-carrageenan. A common post-harvest practice among local farmers involves drying the seaweed using the hanging method, often with exposure to rain. This study investigates the effects of rainwater exposure on the carrageenan yield and quality, as well as the dry yield biomass, of K. alvarezii. Four rainwater soaking times (0, 30, 60, and 90 min) were applied to both fresh and dried forms of K. alvarezii. The samples were then dried or re-dried, and their carrageenan properties were analyzed. Results indicate that rainwater significantly reduces dry yield biomass in both fresh and dried forms, while substantially improving carrageenan yield. In its fresh form, exposure to rainwater notably increased gel strength after 90 min of soak. However, when dried seaweed was soaked and re-dried, gel strength was reduced. Rainwater generally had no effect on viscosity or syneresis index. Gelling temperature was significantly affected by rainwater exposure in fresh seaweed but not in dried samples. Melting temperature in fresh forms was unaffected, but rainwater exposure reduced it in dried seaweed after 90 min of soak. Moisture content was significantly reduced by rainwater in both fresh and dried forms. This research highlights the potential impacts of rainwater on the post-harvest processing of Kappaphycus.

Kappaphycus alvarezii是一种具有商业价值的拟真鱼类海藻，因其含有kappa- carrage胶而在赤道地区广泛种植。当地农民在收获后的一种常见做法是用悬挂的方法晒干海藻，通常是在雨中曝晒。本文研究了雨水暴露对鹿角胶产量、品质和干产量生物量的影响。对新鲜和干燥形式的alvarezii施加4种雨水浸泡时间（0、30、60和90 min）。然后将样品干燥或再干燥，并分析其卡拉胶性质。结果表明，雨水显著降低了新鲜和干燥形式的干产量生物量，同时显著提高了卡拉胶产量。在其新鲜形式下，暴露在雨水中浸泡90 min后，凝胶强度显著增加。然而，当干燥的海藻被浸泡和再干燥时，凝胶强度降低。雨水一般对黏度和增效指标没有影响。雨水暴露对鲜海藻胶凝温度有显著影响，而对干海藻胶凝温度无显著影响。新鲜形式的融化温度不受影响，但在浸泡90 分钟后，雨水暴露降低了干燥海藻的融化温度。新鲜和干燥形式的雨水都显著降低了水分含量。本研究强调了雨水对木柏采后加工的潜在影响。

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引用次数: 0

A living fossil charophyte Lychnothamnus barbatus newly found in southern Siberia (North Asia) 在西伯利亚南部（北亚）新发现的一种活化石charophyte Lychnothamnus barbatus

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-11-23 DOI: 10.1016/j.aquabot.2024.103836

Denis Yu. Efimov , Lyudmila A. Efimova , Roman E. Romanov

Lychnothamnus barbatus (Charophyceae, Characeae), one of the rarest relict macroscopic charophyte species in the world, has a distinct disjunctive range, having been known from fossil remains in northern Asia for a long period. Living plants of Lychnothamnus barbatus were found in freshwater lakes in southern Siberia in the Minusinsk forest-steppe (south of Krasnoyarsk Territory, Russia), within a conservation area in the Shushenskii Bor National Park. These sites are the first ones in Siberia and North Asia. The localities are situated far from known extant records from Central and Eastern Asia, which confirms the uniqueness and vulnerability of the extant habitats.

barbatus Lychnothamnus （Charophyceae, chareae）是世界上最罕见的宏观蕨类孑遗物种之一，具有明显的分离范围，在北亚的化石遗骸中已经发现了很长时间。在西伯利亚南部Minusinsk森林草原（俄罗斯克拉斯诺亚尔斯克地区南部）的淡水湖中，在Shushenskii Bor国家公园的一个保护区内发现了活的Lychnothamnus barbatus植物。这些遗址是西伯利亚和北亚的第一批遗址。这些地点与已知的中亚和东亚现存记录相去甚远，这证实了现存栖息地的独特性和脆弱性。

引用次数: 0

Intra and inter specific variation of propagule settings of the family Rhizophoraceae in the Sundarbans mangrove forest 孙德尔本斯红树林根瘤菌科繁殖体设置的内部和内部特异性变异

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-11-15 DOI: 10.1016/j.aquabot.2024.103834

Md. Kamruzzaman, Md. Minarul Islam, Neyamat Hossen

The Sundarbans mangrove forest in Bangladesh is home to the Rhizophoraceae family, which includes at least 7 species. Understanding the factors influencing mangrove species regeneration in specific areas, such as propagule dispersal, predation, and soil conditions, is crucial for comprehending how these populations establish and grow successfully in changing environments. However, there is limited research on the reproductive phenology of Rhizophoraceae in the Sundarbans. Our research was primarily focused on analyzing and comparing the reproductive phenology of three specific species, Bruguiera sexangula (Lour.) Poir., Rhizophora mucronata Lam., and Kandelia candel (L.) Druce within this diverse ecosystem. We studied the flowering pattern, conversion rate, and growth stages of the reproductive organs of these three species. Both inter- and intra-specific variations in propagule mass and size were also investigated. Our findings revealed that the flowers of these species were present for almost half of the year, with a monthly flowering peak occurring primarily in April and May. The propagule of R. mucronata (60.3 cm) was the longest in size which significantly varied from those of K. candel and B. sexangula. While the diameter and weight of the propagules of B. sexangula and K. candel were similar, they were significantly different from those of R. mucronata. In terms of length and surface area, there were significant variations among the propagules of the studied species. The mean surface area of the propagule was 359.7 cm² in R. mucronata, 232.8 cm² in K. candel, and 62.2 cm² in B. sexangula. Regarding litterfall contribution, reproductive organ production in B. sexangula accounted for 29.1 %, in K.candel it was 37.7 %, and in R.mucronata it was 34.6 %. Our findings suggest that the production of reproductive organs in this mangrove forest is influenced by climatic factors as well as the specific adaptive characteristics of each species rather than solely dependent on the size of the reproductive organs.

孟加拉国的孙德尔本斯红树林是红树科植物的家园，其中至少有 7 个物种。了解影响特定地区红树林物种再生的因素（如繁殖体传播、捕食和土壤条件），对于理解这些种群如何在不断变化的环境中成功建立和生长至关重要。然而，有关孙德尔本斯地区根瘤菌科植物繁殖物候学的研究十分有限。我们的研究主要集中在分析和比较三个特定物种，即 Bruguiera sexangula (Lour.) Poir.、Rhizophora mucronata Lam 和 Kandelia candel (L.) Druce 在这一多样化生态系统中的生殖物候学。我们研究了这三个物种的开花模式、转化率和生殖器官的生长阶段。我们还研究了繁殖体质量和大小在种间和种内的变化。我们的研究结果表明，这些物种的花期几乎占全年的一半，每月的开花高峰主要出现在四月和五月。R. mucronata 的繁殖体（60.3 厘米）最长，与 K. candel 和 B. sexangula 的繁殖体相比差异显著。虽然 B. sexangula 和 K. candel 的繁殖体直径和重量相似，但它们与 R. mucronata 的繁殖体有显著差异。在长度和表面积方面，研究物种的繁殖体之间存在显著差异。R. mucronata的繁殖体平均表面积为359.7平方厘米，K. candel为232.8平方厘米，B. sexangula为62.2平方厘米。在落叶贡献率方面，B. sexangula 的生殖器官产量占 29.1%，K.candel 占 37.7%，R.mucronata 占 34.6%。我们的研究结果表明，这片红树林的生殖器官产量受气候因素和每个物种的具体适应特征的影响，而不仅仅取决于生殖器官的大小。

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引用次数: 0

Fragment viability, regenerative capacity and protoplast isolation of invasive Australian swamp stonecrop (Crassula helmsii) 入侵的澳大利亚沼泽石竹（Crassula helmsii）的碎片活力、再生能力和原生质体分离

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-11-15 DOI: 10.1016/j.aquabot.2024.103835

Menno W.J. Bok , Janneke M.M. van der Loop , Hein H. van Kleef , Rob S.E.W. Leuven

Australian swamp stonecrop (Crassula helmsii) is an amphibious plant native to Australasia and highly invasive in Europe. Managing the spread and impacts of this invader is challenging due to its ability to regenerate from small vegetative plant fragments. In several infested water systems in the Netherlands, the dispersal of this species is currently being prevented using water filters with a mesh size as small as 1 mm² in their outflows. However, it remains unclear whether these filters are truly capable of preventing the spread of small regenerative fragments. To identify potential shortcomings in the management of C. helmsii dispersal, we investigated the regeneration of detached vegetative fragments. A laboratory experiment was conducted to study the regenerative capacity of C. helmsii fragments of varying sizes (0.5–2 mm). We examined the growth performance (stem count, cumulative stem length) of fragments originating from nodes, leaves, shoots, roots, and meristem tissue cuts. All fragments originating from nodal tissue were able to successfully regenerate. Isolated meristem tissue of 0.5 mm was able to regenerate but exhibited malformed growth. Shoot tips demonstrated the best growth performance. While we successfully isolated protoplasts from C. helmsii node tissue, our cultures were compromised, and regeneration could not be assessed. Our research indicates regenerative potential from node fragments as small as a cluster of apical meristem cells. These findings suggest shortcomings in current measures for dispersal prevention of C. helmsii, as they do not prevent the dispersal of plant fragments with a length <2 mm. We recommend re-evaluating the effectiveness of various types of dispersal barriers currently applied in vulnerable natural areas to prevent the spread and subsequent regeneration of small vegetative fragments of C. helmsii.

澳大利亚沼泽石竹（Crassula helmsii）是一种原产于澳大拉西亚的两栖植物，在欧洲具有很强的入侵性。由于这种入侵植物能从小植株碎片再生，因此管理其扩散和影响具有挑战性。目前，在荷兰几个受侵扰的水系中，使用网眼小至 1 平方毫米的滤水器防止该物种扩散。然而，目前还不清楚这些过滤器是否真的能够防止小型再生碎片的扩散。为了找出螺旋藻传播管理中的潜在缺陷，我们对脱离的无性碎片的再生进行了调查。我们进行了一项实验室实验，研究不同大小（0.5-2 毫米）的头鹤草（C. helmsii）碎片的再生能力。我们考察了来自节、叶、芽、根和分生组织切口的碎片的生长表现（茎数、累积茎长）。所有来自节组织的片段都能成功再生。0.5 毫米的分离分生组织能够再生，但表现出畸形生长。芽尖的生长表现最好。虽然我们成功地从 C. helmsii 节组织中分离出了原生质体，但我们的培养物受损，无法评估再生能力。我们的研究表明，小到一簇顶端分生组织细胞的节点碎片都具有再生潜力。这些研究结果表明，目前防止螺旋藻扩散的措施存在缺陷，因为这些措施无法防止长度为 2 毫米的植物碎片扩散。我们建议重新评估目前在脆弱的自然区域使用的各种类型的扩散屏障的有效性，以防止螺旋藻小植株片段的扩散和随后的再生。

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引用次数: 0

Hormonal profiles in shoot apices in (sub)tropical populations of the aquatic carnivorous plant Aldrovanda vesiculosa in summer and winter 水生食肉植物 Aldrovanda vesiculosa（亚）热带种群夏季和冬季嫩枝顶端的激素特征

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-11-13 DOI: 10.1016/j.aquabot.2024.103833

Lubomír Adamec , Lenka Plačková , Karel Doležal

We compared hormonal profiles (cytokinins, auxins, ABA) in shoot apices in six (sub)tropical populations of the aquatic carnivorous plant Aldrovanda vesiculosa (Droseraceae; one from Botswana, five from Australia) growing in cultures during summer and then in frosty conditions at the beginning of winter. One Australian population (Armidale, E Australia, NSW) formed dormant turions. No crucial differences in cytokinin and auxin profiles (for both total and active forms) were found between summer and winter shoots within single populations or between non-dormant and dormant populations in the summer or the winter. The ABA content, as a hormonal criterion for plant dormancy, was consistently nearly zero in summer growing plants in all populations. In winter plants, a nearly zero ABA content occurred only in African plants from Botswana, whereas medium-high ABA contents (3.5–7.0 µmol kg⁻¹; dry weight) were found in all Australian plants regardless of their dormancy. Different Quaternary migration history from southern Europe and subsequent separate evolution and genetic changes might explain the difference between these Australian and African plants. Generally, these results raise questions about how turion formation and dormancy are regulated in plant species with turions with zero ABA content and how other non-dormant subtropical or temperate species overwinter with high ABA content.

我们比较了六种（亚）热带水生食肉植物 Aldrovanda vesiculosa（Droseraceae，一种产自博茨瓦纳，五种产自澳大利亚）芽尖中的激素谱（细胞分裂素、辅助素、ABA）。一个澳大利亚种群（澳大利亚东部，新南威尔士州，阿米代尔）形成了休眠的转塔。在单个种群的夏季和冬季嫩枝之间，或在夏季或冬季的非休眠和休眠种群之间，细胞分裂素和辅助素（总含量和活性含量）没有发现明显差异。作为植物休眠激素标准的 ABA 含量在所有种群的夏季生长植株中始终接近零。在冬季植物中，只有来自博茨瓦纳的非洲植物的 ABA 含量几乎为零，而所有澳大利亚植物的 ABA 含量（3.5-7.0 µmol kg-1；干重）均为中等偏上，与休眠期无关。来自南欧的不同的第四纪移民历史以及随后的单独进化和遗传变化可能解释了这些澳大利亚和非洲植物之间的差异。总的来说，这些结果提出了一些问题，即在 ABA 含量为零的植物物种中，如何调节炮塔的形成和休眠，以及其他非休眠的亚热带或温带物种如何在 ABA 含量较高的情况下越冬。

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引用次数: 0

Variation of carbon and nitrogen stable isotope composition in leaves and roots of Littorella uniflora (L.) Asch. in relation to water pH and nutrient availability Littorella uniflora (L.) Asch.叶片和根中碳和氮稳定同位素组成的变化与水的 pH 值和养分供应的关系

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-11-05 DOI: 10.1016/j.aquabot.2024.103832

Eugeniusz Pronin , Marek Merdalski , Rafał Ronowski , Krzysztof Banaś

In a phytotron experiment, the effects of pH variation and eutrophication on isoetids plants from soft-water lakes specifically the submerged form of Littorella uniflora (L.) Asch. was investigated by analyzing stable carbon and nitrogen isotopes (δ¹³C and δ¹⁵N). Conducted in late October 2020, 200 specimens from Lake Zawiad, near Gdansk, Poland, were examined over 75 days. The study tested three pH levels (∼4.5, ∼7.0, and ∼8.5) and a detailed 12-step nutrient gradient (nitrogen: 0–10 mg/l; phosphorus: 0–0.3 mg/l). The analysis focused on isotopic composition in leaves and roots, revealing that acidic conditions favored higher δ¹³C values (leaves: −22.67 ‰; roots: −23.23 ‰), suggesting a preference for lighter carbon forms in photosynthesis and intensive use of limited sources of CO₂. The neutral pH variant showed the lowest δ¹³C values (leaves: −25.53 ‰; roots: −25.47 ‰), indicating less optimal conditions. δ¹⁵N values exhibited minimal fluctuation across pH levels, with slight variations in acidic and alkaline environments compared to neutral conditions. An observed decrease in δ¹³C across all pH levels with increased nutrients, alongside a rise in δ¹⁵N values, indicates a complex interaction between isotopic composition and environmental factors. Our findings suggest that L. uniflora shows a distinct isotopic response to varying pH levels, with higher δ¹³C values under acidic conditions potentially indicating enhanced CO₂ uptake through a specialized carbon assimilation strategy. This highlights the species' adaptive mechanisms to environmental stressors, suggesting that the isotopic composition of aquatic vegetation can serve as a sensitive indicator of changes in lake ecosystems.

在一项植物实验中，通过分析稳定的碳和氮同位素（δ13C 和 δ15N），研究了 pH 值变化和富营养化对软水湖泊中异叶植物的影响，特别是 Littorella uniflora (L.) Asch.这项研究于 2020 年 10 月下旬进行，对波兰格但斯克附近扎维亚德湖的 200 个标本进行了为期 75 天的检测。研究测试了三个 pH 值水平（∼4.5、∼7.0 和∼8.5）和详细的 12 级营养梯度（氮：0-10 毫克/升；磷：0-0.3 毫克/升）。分析的重点是叶片和根部的同位素组成，结果表明，酸性条件下的δ13C 值较高（叶片：-22.67 ‰；根部：-23.23 ‰），这表明光合作用偏好轻碳形式，并大量利用有限的二氧化碳来源。中性 pH 值变体的 δ13C 值最低（叶：-25.53 ‰；根：-25.47 ‰），表明其条件较差。δ15N值在不同的pH值水平下波动很小，与中性条件相比，酸性和碱性环境中的δ15N值略有变化。随着养分的增加，在所有 pH 值水平上观察到的δ13C 值下降，同时δ15N 值上升，这表明同位素组成与环境因素之间存在复杂的相互作用。我们的研究结果表明，L. uniflora 对不同的 pH 值有不同的同位素反应，在酸性条件下，δ13C 值较高，这可能表明其通过专门的碳同化策略提高了对二氧化碳的吸收。这凸显了该物种对环境压力的适应机制，表明水生植被的同位素组成可以作为湖泊生态系统变化的敏感指标。

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引用次数: 0

The influence of physicochemical variables on plant species richness and distribution in the coastal salt marshes of the Berg River Estuary, South Africa 物理化学变量对南非伯格河口沿海盐沼植物物种丰富度和分布的影响

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-10-28 DOI: 10.1016/j.aquabot.2024.103831

Nomcebo T. Mngomezulu , Anusha Rajkaran , Dimitri A. Veldkornet

The continuous distribution of coastal salt marsh habitats along an elevation gradient can be disrupted by tidal creeks running through them. Tidal creeks wind through salt marshes and create different environmental conditions for adjacent habitats. While studies have emphasized the importance of tidal creeks as links facilitating interactions in salt marshes, few have studied plant communities and physiochemical conditions associated with tidal creeks. This study determined the influence of creek physicochemical variables on the diversity and distribution of coastal salt marsh plants. Six transects in the lower reaches of the Berg River Estuary, South Africa were sampled over two seasons at sites with either the presence or absence of creeks. Species composition and abundance were analysed by replicate quadrats and paired with physicochemical variables (groundwater and sediment). The k-means of 20 species in 334 quadrats revealed four distinct clusters of salt marsh habitats, creeks, intertidal salt marsh, supratidal salt marsh and reeds. Species richness was higher along transects with creeks (16) compared to those with no creeks (5). The physiochemical variables, groundwater temperature, pH, dissolved oxygen, conductivity, and sediment variables (redox potential, organic content, percentage silt and percentage sand), significantly influenced the abundance of creek species. This study highlights the importance of tidal creeks in forming unique vegetation communities in salt marshes, where they act as refugia for intertidal species. It is suggested that tidal creek communities should be included in salt marsh vegetation descriptions and monitored in association with physicochemical variables in response to climate change.

沿海盐沼生境沿海拔梯度的连续分布会被穿过它们的潮汐溪流破坏。潮汐溪流蜿蜒穿过盐沼，为相邻的生境创造了不同的环境条件。虽然研究强调潮汐溪流作为促进盐沼互动的纽带的重要性，但很少有人研究与潮汐溪流相关的植物群落和理化条件。这项研究确定了溪流物理化学变量对沿岸盐沼植物多样性和分布的影响。在南非伯格河口下游的六个横断面上，对有无溪流的地点进行了两季采样。物种组成和丰度由重复的四分区分析，并与物理化学变量（地下水和沉积物）配对。对 334 个四分格中的 20 个物种进行的 k-means 分析显示，盐沼生境有四个不同的群组：溪流、潮间带盐沼、潮上带盐沼和芦苇。与没有溪流（5 条）的横断面相比，有溪流（16 条）的横断面物种丰富度更高。物理化学变量（地下水温度、pH 值、溶解氧、电导率）和沉积物变量（氧化还原电位、有机物含量、淤泥和沙的百分比）对溪流物种的丰富度有显著影响。这项研究强调了潮汐溪流在盐沼中形成独特植被群落的重要性，潮汐溪流是潮间带物种的避难所。建议将潮汐溪流群落纳入盐沼植被描述中，并结合物理化学变量对其进行监测，以应对气候变化。

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引用次数: 0

Multiple introduction events expand the range of the invasive brown alga Rugulopteryx okamurae to northern Spain 多次引入事件扩大了入侵褐藻 Rugulopteryx okamurae 在西班牙北部的分布范围

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-10-24 DOI: 10.1016/j.aquabot.2024.103830

Pilar Díaz-Tapia , Nerea Alvite , Rafael Bañón , Rodolfo Barreiro , Sara Barrientos , María Bustamante , Sara Carrasco , Javier Cremades , Silvia Iglesias , María del Carmen López Rodríguez , Nahiara Muguerza , Cristina Piñeiro-Corbeira , Endika Quintano , F. Javier Tajadura , Isabel Díez

The brown alga Rugulopteryx okamurae is one of the most recent and aggressive marine invaders known, with a non-native range that spans from the western Mediterranean to the southern Iberian Peninsula, and the European Macaronesian archipelagos. Here, we provide the first record of its presence at three disjunct areas from northern Spain, supported by morphological and molecular evidence. Rugulopteryx okamurae was discovered in the port of Bilbao in the northeastern Atlantic of Spain, more than 1200 km away from the nearest invaded location previously known. It was also found at two separate areas in northwestern Spain: San Amaro, a small inlet at the entrance of the port of A Coruña, and Monteferro-Playa América, a site close to the port of Vigo. In two areas, R. okamurae was found to cover up to 100 % of the bottom, suggesting that it may behave as an aggressive invader in northern Spain. Our findings confirm the propensity of R. okamurae for long-distance dispersal and reveal that this invader is expanding its range northwards along the European Atlantic coast.

褐藻 Rugulopteryx okamurae 是已知的最新、最具侵略性的海洋入侵者之一，其非本地分布范围从地中海西部到伊比利亚半岛南部，以及欧洲马卡罗内斯群岛。在这里，我们首次记录了它在西班牙北部三个不相连地区的存在，并提供了形态学和分子证据支持。Rugulopteryx okamurae是在西班牙东北部大西洋的毕尔巴鄂港发现的，距离之前已知的最近入侵地点超过1200公里。它还在西班牙西北部的两个不同地区被发现：圣阿马罗（San Amaro）和蒙特费罗（Monteferro-Playa América），前者是科鲁尼亚港入口处的一个小入口，后者靠近维哥港。在这两个地区，发现 R. okamurae 对海底的覆盖率高达 100%，这表明它在西班牙北部可能是一种侵略性入侵者。我们的研究结果证实了 R. okamurae 的远距离传播倾向，并揭示了这种入侵者正沿着欧洲大西洋海岸向北扩展其范围。

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引用次数: 0

Halophila baillonii's hidden distribution range: Rediscovery and conservation of a rare seagrass in the Tropical Atlantic Halophila baillonii 隐藏的分布范围：热带大西洋稀有海草的重新发现与保护

IF 1.9 4区生物学 Q2 MARINE & FRESHWATER BIOLOGY

Aquatic Botany

Pub Date : 2024-10-19 DOI: 10.1016/j.aquabot.2024.103828

Karine Matos Magalhães , Thomaz Henrique Arruda Lima , Roberto Lima Barcellos , Ana Maria Costa Souza

This study characterizes a population of the rare seagrass species Halophila baillonii, rediscovered over 130 years after its initial record on the Brazilian coast. Historical and current global distribution and species traits were reviewed to investigate population expansion and compare worldwide populations. Generally, seagrass traits of this new population showed no significant differences compared to previously studied populations, including those within Marine Protected Areas. However, a global lack of population data for the species was identified. Thirteen populations were recognized within the Tropical Atlantic Bioregion, with most in multispecific meadows. In these multispecific meadows, H. baillonii leaves were wider. The recent rediscovery of this population raises the question: are we observing a genuine expansion of its distribution range, or have we simply overlooked its presence in certain areas?

这项研究描述了稀有海草物种 Halophila baillonii 的一个种群特征，该种群是在巴西海岸首次记录后 130 多年才被重新发现的。研究回顾了该物种在全球的历史和当前分布情况以及物种特征，以调查种群扩张情况并对全球种群进行比较。总体而言，这个新种群的海草特征与之前研究过的种群（包括海洋保护区内的种群）相比没有明显差异。不过，该物种在全球范围内缺乏种群数据。在热带大西洋生物区内发现了 13 个种群，其中大多数位于多特异性草甸中。在这些多特异性草甸中，H. baillonii 的叶片较宽。最近重新发现该种群提出了一个问题：我们观察到的是其分布范围的真正扩大，还是我们只是忽略了它在某些地区的存在？

引用次数: 0