述评
Review
北京大学学报(自然科学版) 第62卷 第3期 2026年5月
Acta Scientiarum Naturalium Universitatis Pekinensis, Vol. 62, No. 3 (May 2026)
doi: 10.13209/j.0479-8023.2025.109
中国林业科学研究院基本科研业务费专项(CAFYBB2023MA009), 广州市城市森林生态系统效益监测、分析与研究(JYZC-202208-05)和广州市基础研究计划基础与应用研究项目(2024A04J3878)资助
收稿日期: 2025–03–26;
修回日期:2025–09–23
摘要 系统地梳理城市森林植物物候变化特征及其驱动因素相关文献, 结合植物物候事件与鸟类鸣声时空格局耦合关系的研究, 归纳和总结城市化背景下城市森林植物影响鸟类鸣声多样性的内在机制, 得出如下主要结论: 1)城市森林植物物候通过改变食物资源动态、栖息地特征及种间竞争格局, 直接或间接地影响鸟类鸣声多样性; 2)城市森林鸟类通过发声行为适应性地调整与鸣声表型的可塑性变化, 应对物候驱动的资源竞争压力。在未来的城市森林植物物候对鸟类鸣声多样性研究中, 需重点关注鸟类鸣声的季节性变化。可依托新兴监测技术, 搭建物候–声学复合监测网络, 深入解析城市森林植物物候与生物多样性之间的多维度机制。同时, 开展多角度的跨领域合作, 应对城市化进程中生物多样性保护的复杂挑战。
关键词 城市森林; 植物物候; 鸟类; 鸣声多样性; 影响机制; 生物多样性保护
快速城市化进程对生物栖息地和生物多样性构成严峻威胁[1]。城市森林指包含城市区域内所有树木, 涵盖行道树及公园树群等的植被空间[2], 是维持城市生物多样性的关键生境, 能缓冲城市化对生物多样性的威胁[3–4]。作为城市生态系统的重要组成部分, 城市森林在调节气候、提供栖息地以及维护生物多样性等方面发挥着不可替代的作用[5]。鸟类对微气候波动和生态环境变化表现出高度敏感性[6–7], 常作为评估城市生物多样性对城市生态环境变化响应的重要指示物种[8]。鸟类多样性的组成和分布对评估生态系统功能具有重要参考价值, 是生态学研究的热点[9]。鸟类鸣声是鸟类对外界环境敏感性反应的表型特征, 在个体识别、领地防御、吸引配偶及群体交流等方面具有重要作用[10–12]。鸟类鸣声多样性是鸟类生态功能的直接映射, 也是鸟类的环境适应与进化压力作用下的综合结果, 能反映环境质量、资源可利用性以及生态系统的稳定性[13–14]。鸟类在城市森林中的发声空间及发声模式与在自然栖息地中存在差异。在不同城市化水平及气候变化条件下, 城市森林植被对鸟类鸣声的影响存在一定的不确定性。大多数研究关注城市化背景下城市森林结构对鸟类多样性、空间分布规律及鸣声特征变化的影响, 但对森林植物物候变化影响鸟类鸣声多样性的内在机制缺乏系统性的总结。近年来, 被动声学监测技术(pas-sive acoustic monito-ring, PAM)、鸟类鸣声人工智能(artificial intelligen-ce, AI)分析技术及声景指数方法快速发展, 为探究鸟类鸣声多样性对城市化的响应机制和声景下的生物多样性变化格局提供了新的研究途径。
通过梳理城市森林植物物候变化改变栖息地条件、资源供给及声学环境, 进而影响鸟类鸣声多样性的相关研究, 可以更好地理解鸟类发声行为的城市化适应策略, 为城市森林建设中的鸟类多样性保护提供参考。本文将从以下 3 个方面进行总结和探讨: 1)城市森林植物物候变化的主要特征及其驱动因素; 2)植物物候变化对鸟类鸣声多样性的影响机制; 3)未来城市鸟类鸣声多样性研究的发展方向。
本文基于 Web of Science 和中国知网(CNKI)平台, 使用表 1 中检索词, 搜索国内外相关文献, 检索字段为标题和摘要, 使用逻辑运算符“AND”和“OR”组合(同一维度内为 OR, 不同维度间为 AND), 时间跨度为 1975—2025 年。文献类型选择“研究论文”和“综述”。共检索到英文文献 1434 篇, 中文文献 60 篇。然后, 根据标题和摘要内容, 进一步筛选出与“城市森林物候变化影响鸟类鸣声多样性”相关的文献百余篇。从食物资源、栖息地结构、种间关系、行为适应及表型可塑性 4 个方面, 梳理和归纳城市森林物候变化对鸟类鸣声多样性影响的研究 成果。
城市森林通过垂直分层、空间分布以及树种组成等多维结构与复合功能, 提供生物多样性维持、食物资源供给以及声景多样性塑造等生态服务功 能[15–16]。城市森林植物物候指城市绿地系统中植物在长期适应气候条件周期性变化过程中形成的生长发育节律, 这一现象是城市生态系统对气候变化响应最直观的指示器[17]。城市森林物候典型特征包括物候期延长与异步性、微生境分异以及种间物候错位等, 表现在萌芽、展叶、开花、结实和落叶等关键阶段, 是自然因素和人为因素共同驱动的结果[18–20]。自然因素包括温度、气候、光照条件和土壤特性, 人为因素则包含城市热岛效应、污染排放、土地利用变化以及人为管理措施等。例如, 大气污染物(如臭氧、二氧化硫和氮氧化物)可能通过植物的光合作用和呼吸作用改变其生长周期[21]。城市森林植被往往受到集约化管理, 乔灌木的频繁修剪和草本花卉的频繁更替使得城市森林植物物候变得不稳定[22]。在高度城市化区域中, 城市森林的春季物候期通常较周边自然区域有所提前[23–24]。城市热岛效应导致城市区域温度升高, 致使早开花物种的花期和萌芽期提前[25], 植被秋季落叶时间的延迟也与较高的温度密切相关[26], 但也有研究得到与此相反的趋势[27]。此外, 城市森林植物物候的变异性也可能高于自然森林, 主要归因于城市环境中土地利用方式的多样性和人为干扰强度的差异。例如, 道路绿化带、住宅花园等不同生境类型间植物物候存在明显差异, 物候呈现空间碎片化特征。城市森林植物不同物种的响应也存在差异[28]。不同植物对城市环境变化的敏感性不同, 导致其物候事件的发生时间存在较大差异。如杜鹃(Rhododendron simsii)和连翘(Forsythia suspensa)等植物对温度变化尤为敏感, 开花时间显著提前[29]。
表1 文献检索策略
Table 1 Literature research strategy
检索维度英文检索词中文检索词 植物物候Phenology*, Vegetation*, “Plant Phenology”, “Plant Vegetation”, “Floral resources”物候, 植物物候 城市森林Urban*, City*, “Urban green”, “Urban forest”, Urbanization城市, 城市森林 鸟类鸣声多样性Bird*, Avian*, sound, song鸟类, 鸟类鸣声, 声景
说明: *表示通配符, 搜索包含该单词的衍生词; “ ”表示精确搜索引号中的短语。
城市森林植物物候变化不仅反映植物对环境变化的适应策略, 还通过食物资源和栖息地条件, 间接地影响城市生态系统的其他组分, 尤其是鸟类群落。鸟类的出现会根据资源可用性而变化[30], 其季节性波动在一定程度上受食物资源影响[31], 这种群落多样性的变化表现在其鸣声的多样性上。植物群落结构的季节性变化影响鸟类的栖息地和筑巢地选择[32–33], 改变鸟类的发声空间结构, 进而影响其鸣声多样性的时空分布[34]。例如, 物候驱动的资源集中化吸引优势种聚集, 可能压缩其他物种的生态 位[35]。城市森林物候的时空异质性通过“资源再分配–栖息地结构–种间关系”三级链式反应影响鸟类多样性[36–37]。此类机制表明, 城市森林物候变化不仅是植物自身的适应性响应, 更是城市鸟类行为进化的重要选择压力。这些研究进一步揭示了城市森林植物物候变化对生态系统功能的深远影响。
鸟类发声方式主要分为两大类: 鸣叫(call)和歌唱(song)。鸣叫是简单而短暂的发声, 鸟类通过鸣叫在鸟群内部甚至不同物种间进行交流, 如警报鸣叫[38]。歌唱是长而复杂的发声, 鸟类通过歌唱来进行领土防御或吸引配偶。目前主要应用声纹设备收集鸟鸣声。鸟类鸣声多样性指鸟类鸣声在多种维度上的复杂性和差异性, 反映鸟类个体、种群或群落在声音信号层面的丰富程度和生态适应性[39]。鸟类鸣声多样性不仅是生物多样性研究的重要组成部分, 也是评估生态系统功能、物种行为适应性和声景健康的关键指标[40]。鸟类的鸣声多样性可从声学特征、功能类型、时间分布、空间分布及声学指标 5 个层面来阐述。鸟鸣的声学特征多样性指鸣声的物理属性差异, 包括频率、时长和能量分布等基本参数以及调制模式的复杂性。鸣声功能类型多样性指鸣声的行为功能分类, 如求偶、警戒和领域防御等。时间分布多样性指鸟类鸣声在昼夜、季节或繁殖周期内具有一定的变化规律, 如鸟类的黎明合唱。空间分布多样性指鸟类鸣声在不同生境或地理区域中的分布差异, 如方言差异。声学指标是从群落或生态系统尺度, 量化整体声学环境多样性的快速简便工具, 可反映多种生物学和生态学特征[41], 如物种丰富度、多样性和多度[42–43], 动物群落发声活动的日变化和季节性变化[44]以及栖息地结构差异等[45–46]。常用的声学指标包括声熵指数(acoustic entropy index, H)[47]、声学复杂度指数(acoustic com-plexity index, ACI)[48]、声学多样性指数(acoustic diversity index, ADI)[49]、生物声学指数(bioacoustic index, BIO)[50]、声学均匀度指数(acoustic evenness index, AEI)[49]以及归一化声景差异指数(normalized difference sound index, NDSI)[51]等。鸟类鸣声多样性量化方法不仅可为生物多样性监测服务, 也可为生态保护和动物行为学研究提供重要工具。
作为城市化进程中重要的生态基础设施, 城市森林不仅是人与自然互动的纽带, 更是维持生物多样性的关键生境[52]。城市森林通过植被的时空配置为鸟类提供栖息、觅食和繁殖的场所, 其植物物候特征直接决定资源的可利用性。鸟类鸣声多样性是鸟类多样性的重要表征, 包含个体行为适应、种间竞争及环境压力等信息[53–54], 其声学指数反映鸟类丰富度和多样性[55–56]。鸟类鸣声的功能多样性与植物物候驱动的资源分布紧密相关。城市植物物候变化通过食物链、栖息地结构和种间关系互作网络的多级传递, 促使鸟类行为及其表型可塑性发生适应性改变, 最终通过鸟类鸣声多样性表现出来(图 1)。
传统的鸟类多样性调查方法主要有样线(样点)调查法和标记重捕法等。样线(样点)调查需要大量野外作业, 持续时间长, 专业技术要求高, 耗费较大的人力、物力和财力, 导致采集的数据量十分有限, 且结果易受观察者主观感知、经验判断和专业知识影响[57]。标记重捕法则适用于特定的物种研究, 对鸟类干扰较大。传统鸟类监测方法受限于时空覆盖率和人工效率。近年出现的红外监测和被动声学监测技术弥补了传统监测方法的不足, 可实现长期、无干扰性、连续性和客观性监测, 为探究城市化对生物多样性的影响提供了更多的研究手段。红外监测能够直观地获取鸟类形态和行为数据, 但易受光线干扰, 并受到分辨率不足以及镜头易被遮挡等因素限制, 还存在数据储存量大和传输需求高等问题[58]。被动声学监测技术可全天候监测, 环境适应性更强, 不受天气条件限制, 支持大尺度长期性的研究, 音频数据储存量小, 传输成本低。但是, 声纹设备只能收集声音数据, 在没有人工标记或视频补充的条件下难以区分个体, 当前的 AI 算法模型也亟需优化其鸟类识别精度[59–60]。此外, 被动声学监测指标的阈值尚未明确, 亟需制定科学的技术规范和声学评价体系来提升声学数据的可比性[61], 推进标准化平台建设, 从而推动生物多样性智慧监测技术的发展。
图1 城市森林植物物候对鸟类鸣声多样性影响机制示意图
Fig. 1 Schematic diagram of the impact mechanism of urban forest plant phenology on bird sound diversity
植物物候监测主要观测植物生长发育的周期性变化, 方法较为成熟。传统的人工观测法依赖人工定期记录植物的物候阶段, 成本低且灵活性较强, 适用于小范围和特定物种的长期调查, 缺点是数据受人为经验和主观判断影响, 误差较大, 精确度较低, 无法实现连续监测, 易错过关键物候节点, 需长期投入人力。目前多应用地面自动化监测、遥感和植物生理生态监测系统等方法进行高质量、长期性和标准化的植物物候监测。地面自动化监测通过部署多光谱相机和传感器网络等设备, 实现植物物候的自动化采集, 全天候获取高精度和多参数数据, 适用于偏远地区的长期监测, 但成本和技术水平要求高, 数据处理过程复杂[62]。卫星和无人机等遥感技术能获取大范围的植被物候信息, 减少对自然生境的干扰, 利用长期卫星数据可高效地获取物候数 据[63], 但受天气影响较大, 且依赖算法提取物候参数时, 易引入误差[64]。
3.2.1 食物资源变化
食物资源是决定鸟类丰富度的关键限制性因子, 也是影响鸟类空间分布格局的主要驱动因素[65]。
物候重叠是鸟类与植物之间相互作用的主要决定因素[66]。在城市森林斑块面积足够大的情况下, 食果鸟类多样性与果树的物种丰富度及成熟果实数量之间呈现显著的正相关关系[67]。尤其在旱季资源稀缺期, 鸟类更倾向聚集于食源植物丰富的区域, 进而形成高密度鸣声群落。城市森林中的食源植物在不同物候期的花蜜产量和结实量决定鸟类的造访程度。在人类主导的环境中, 通常存在水分和营养增加的情况, 进而影响植物开花和结实等物候, 而城市食源植物的花卉和果实生产力决定鸟类的造访程度。食蜜鸟类群落的动态变化与花蜜来源和产量的多样性相关[68]。例如, 在城市街道中, 桉树花期数量可以显著预测食蜜鹦鹉的分布[69]。蜂鸟(Trochili-dae)物种的访问次数与开花植物的花量相关, 其取食次数随着开花植物的花总数增加而增加[70]。城市森林植物群落中具有更丰富多样的外来物种, 在物候上与本土植物形成互补, 如在新西兰 Dunedin市, 外来的栎树(Quercus robur)在所有季节为鸟类提供觅食机会[71]。当本土花卉稀缺时, 外来植物可提供充足的花蜜资源[72]。城市森林植物花期的延长也会增加花蜜资源, 这种资源的易获得性可支持更高密度的食蜜鸟类[69]。如在开花量整体偏低的城市区域, 外来物种凭借花蜜糖分浓度更高的花卉吸引蜂鸟及其他几种食蜜鸟造访[73–74]。因此, 城市森林中花卉资源的多样性也是维持食蜜鸟在城市中生存繁育的关键因素[75]。但是, 外来物种的果实并没有被食果鸟类优先取食[76], 特定颜色果实的常绿本土植物会吸引更多样的鸟类[77]。在食物缺乏的情况下, 替代食物来源有限, 食虫鸟类可能会取食秋冬季植物果实, 城市景观中的浆果则成为鸟类冬季重要的营养来源之一[78]。
城市森林植物物候可以通过改变三级营养链而影响城市鸟类分布。食物限制假说(Food Restriction Hypothesis)指出, 昆虫丰度和可用性不足会降低城市鸟类繁殖成功率[79]。如鳞翅目幼虫是食虫鸟类食物的重要组成部分[80], 城市地区较高的温度和植物发芽日期的提前可能造成鳞翅目幼虫的丰度高峰提前, 从而导致食虫鸟类育雏成功率下降[81–82], 进而减少鸣声交流的频率和复杂性。依赖单一食源的专食性鸟类可能因物候错配而导致食物资源短缺, 进而引发种群衰退, 其独特鸣声类型随之减少, 而白头鹎(Pycnonotus sinensis)等杂食性鸟类的通用型鸣声占比增加[83], 造成城市森林中鸣声的多样性下降[84]。此外, 在食物相对匮乏的环境下, 营养不足的幼鸟可能因学习能力受损, 导致其鸣叫准确度下降或复杂性降低[85]。物候错配假说(Phenological Mismatch Hypothesis)则指出, 在气候变化下, 当出现与其他生物物候不同步、不匹配的情况时, 鸟类会调整关键生活史事件的发生时间[86]。Slagsvold等[87]的长期监测结果证实, 蓝山雀(Cyanistes cae-ruleus)和大山雀(Parus major)能够追踪环境物候, 最大化地获取随空间和时间变化的食物资源。繁殖时间与最佳资源丰富度相匹配, 对城市鸟类的繁殖成功率至关重要[88]。
3.2.2 栖息地变化
城市森林植物物候动态地影响栖息地的质量和结构, 鸟类群体的分布因此发生改变, 鸟类鸣声的时空格局也随之改变, 并影响鸟鸣声的传播效率。栖息地的食物资源变化影响鸟类的时空分布。Blin-kova 等[89]的研究结果揭示了鸟类多样性与开花植物丰富度之间的正相关关系。城市森林春季和秋季物候的提前或延迟改变昆虫爆发期和果实成熟期的同步性, 动态地影响着不同食性鸟类的栖息地选择, 尤其是长距离迁徙的鸟类。春季返青时间与迁徙时间脱钩, 迁徙鸟类会错过季节性生产力高峰, 造成繁殖失败, 进而导致迁徙种群普遍下降[90], 该区域的鸣声多样性也可能随之减少。栖息地配置(如植被覆盖率、物种组成和树种丰富度等)与鸟类物种丰富度和丰度之间关联密切[91], 鸟类多样性会随着植被复杂性的增加而增加[92]。植被覆盖的季节性变化对鸟类繁殖也会产生影响。Monniez 等[93]研究城市公园中噪声和植被覆盖率对城市鸟类分布和繁殖率的影响, 发现大山雀的产卵日期随着植被覆盖率的增加而推迟, 蓝山雀的孵化成功率与噪声水平负相关, 而与植被覆盖率正相关。鸟类数量则可能增加声学信号的多样性和复杂性[47]。“全叶”假说(‘Total-Foliage’ Hypothesis)指出, 更密集的植被覆盖可以更好地保护鸟类躲避天敌[94–95]。林下植被影响鸟类的视觉、听觉和栖息物理环境, 例如, 寒冷地区秋冬季林下植被减少, 可能提升啄木鸟(Pici-dae)等视觉导向鸟类对捕食者的探测能力[96–97]。
通过植物覆盖度、冠层密度及垂直结构的季节性调整, 植物物候变化可以重塑鸟类栖息地的声学环境, 驱动鸟类鸣声的适应性变化[44,98–99]。栖息地结构是塑造鸟类声学空间的关键因素[61]。城市森林植被结构的季节性变化通过声波传播特性直接影响鸟类鸣声的传递效率与竞争策略。例如, 春季展叶期冠层密度增加, 会减弱大山雀的高频声波的传播效率[100], 迫使鸟类通过调整鸣声频率来增强信号传递。长期的被动声学监测数据表明, 夏季城市植物茂密的冠层可吸收低频人声及环境噪音, 为鸟类提供“声学避难所”[101–103]。由于秋冬季落叶休眠, 植被结构简化, 可能导致声景异质性降低, 鸟类鸣声多样性指数随之下降, 表明植被结构的复杂型是维持声学多样性的关键[104]。另一方面, 简单的植被空间结构也可能存在更丰富的鸣声活动, 鸟类通过调整鸣声主频、音节长度和重复速率, 适应植被结构变化带来的声波衰减效应[105–107]。如在破碎化生境中, 稀疏的乔木层和扩张的林下空间增强了高频噪音的穿透性, 迫使鸟类通过提高鸣声主频来增强信号的传递效率[108]。虽然这种适应性调整缓解了短期内的声学竞争, 但长期可能导致鸣声趋同化, 降低种间识别能力[109]。因此, 季节性变化影响着城市森林声景与植被类型之间的相关性。南京湿地公园中的植被特征季节性变化可以解释不同时间尺度上鸟鸣频带分布的大部分变化[110]。鸟类在不同植被类型中表现出季节性偏好, 其鸣声多样性的季节性也表现明显[111–112]。冬季的鸟鸣声模式与春秋季明显不同, 具体表现为春秋两季为迁徙和繁殖旺季, 鸟类鸣叫多样性增加。这种鸟鸣模式与植物物候变化调控的栖息地结构变化密切相关。
3.2.3 种间关系变化
植被物候在时空尺度上对鸟类物种丰富度和生态位竞争具有重要影响[113]。植物物候变化通过调控食物资源的时空分布来改变鸟类种间关系。城市热岛效应会导致城市森林植物季节性变化普遍提前, 生长季持续时间更长[20]。城市森林中外来植物与本土植物的物候错配, 延长了食物资源的供应期, 能缓解本地资源季节性短缺引发造成的种间竞争。这种竞争体现在鸟类鸣声的多样性上。资源供应时间与鸟类物候错配也可能导致原本的资源不可用, 迫使物种转向重叠生态位, 加剧种间竞争。城市森林植物春季物候提前, 导致鸟类育雏与昆虫爆发期错位, 食虫鸟类的食物供应不足, 鸟类种间竞争加剧, 鸣声可能因争夺资源而趋向高频或复杂化。城市森林中昆虫生物量下降也会导致食虫鸟类(如柳莺属(Phylloscopus))的繁殖领地缩减, 同时杂食性鸟类通过提高种子取食比例来补偿蛋白质摄入的不 足[114]。资源丰富的区域可能会吸引更多的个体, 促进鸣声类型的分化与竞争。城市森林中植被物种较为单一的栖息地, 其植物物候的高度同步导致果实成熟期集中, 可能吸引白头鹎和乌鸦(Corvus)等鸟类聚集, 引发短时间内的高强度竞争。育雏期食虫鸟类的数量和觅食活动增加[115], 非食虫鸟类也可能捕食昆虫来喂养幼雏, 捕食压力会随着食虫鸟类多样性的增加而增加[116]。声学生态位假说(Acou-stic Ecological Niche Hypothesis, ANH)认为, 物种间竞争会促进不同物种发出在时间和频率上出现分化的声音[117], 表明在城市环境过滤下的鸟类通过鸣声在城市森林声景中占据生态位。如白头鹎在北扩过程中, 新建种群会因食物资源差异而展出简化的鸣唱类型库, 表现出“文化漂变”现象[118]。
城市森林栖息地破碎化背景下的物候变化调控资源分布以及种间竞争, 影响着鸟类物种丰富度和丰度[119], 鸣声多样性可能呈现“赢家通吃”的格局, 即该区域声学环境由优势种鸣声主导。此外, 鸟类会依赖“资源岛”, 种间攻击行为(如领域驱逐等)的频率上升, 弱势物种被边缘化, 直接降低鸣声多样性指数。若优势种的声学信号强化, 则会进一步挤压弱势物种的繁殖成功率, 最终改变群落的鸟类鸣声类型组成。同一营养级的鸟类对物候变化的响应差异也可能影响竞争物种的共存, 如常驻的大山雀和迁徙的斑鹟(Ficedula hypoleuca)会在春季争夺巢 地[120]。植物–昆虫物候链断裂(如昆虫孵化滞后于植物生长节点)导致鸟类跨生态位觅食, 触发种间资源争夺。植物物候变化也会影响捕食者(如猛禽、猫科动物等)的活动模式, 迫使鸟类调整自身鸣声的发生时间和地点来应对被捕食威胁。
3.2.4 行为适应与表型可塑性
城市森林植物物候变化通过资源分布、栖息地结构和声学环境的多维调控, 驱动鸟类行为适应性的改变。城市森林外来植物与本土植物形成的资源互补效应能缓解资源的季节性短缺, 促使鸟类调整觅食范围和时间分配。这种物候错配可能导致鸟类对资源的竞争加剧, 迫使鸟类扩大觅食范围或改变鸣声策略。如春季物候延迟, 导致植被覆盖度不足, 巢穴暴露风险增加, 鸟类可能通过减少鸣叫时长来避免被捕食。植物物候变化在一定程度上影响鸟类的迁徙和繁殖行为。例如, 城市鸟类会根据生境中的资源来微调产蛋时间, 以便雏鸟的留巢期与本地食物供应时间的高峰期吻合[121]。此外, 食物资源和筑巢机会的稀缺会降低鸟类分布和功能的多样性, 使城市鸟类群落逐渐以栖息地和食性广泛的种类以及低移动性的留居物种为主, 群落结构趋于同质化[122], 鸟类鸣声多样性下降。
长期的城市森林植物物候压力可能驱动鸟类鸣声复杂性、音频和节奏等特征的适应性演化[54,85,123]。声学适应性假说(Acoustic Adaptation Hypothesis, AAH)认为, 鸟类会根据其所处环境, 在发声上做出适应性的改变, 以便提高声音传输的效率[124], 如调整自身鸣声特征或时间来降低城市森林中其他生物声和噪声对其声音传递的负面影响[125–126]。研究表明, 许多鸟类的迁徙和繁殖时间都因春季气候变暖而提前[127]。城市森林中鸟类的鸣叫期更长, 开始时间更早[61,128]。这种情况出现的原因可能是城市森林的春季物候提前, 资源供应时间延长, 导致鸟类行为发生适应性改变[129]。例如, 部分城市森林鸟类的歌唱物候因食物供应、捕食者类型和植被物候不同而存在明显的差异, 在冬季形成较小的非繁殖群体, 在春季开始较早地开始唱歌[130]; 但温度变化也会影响其歌唱物候的变化, 导致优势种以更高的密度占领领地。
城市森林内部植被结构和空间结构对鸣声的传播强度和距离均造成影响。城市森林植物物候通过改变植被的吸声系数、反射效率和散射作用等[131], 驱动鸟类调整鸣声来适应声景变化。繁殖季节鸟类鸣叫最为活跃, 此时城市森林的声学环境会经历巨大的季节性变化。城市森林春季植被生长加快和树叶绽放会对鸟类鸣声传播造成负面影响, 由于树叶散射和吸收声音的总量增加, 导致鸣声衰减, 缩小了鸟类发声活动空间, 使其声音交流变得更加困 难[100]。在城市森林植被的落叶期, 开放空间的增加会增加鸟类暴露的风险, 若红嘴蓝鹊(Urocissa erythroryncha)的警戒声被其他鸟类识别, 可能抑制其特异性鸣声表达[132]。另有研究表明, 在复杂地形中, 鸟类倾向发出声强分布均匀的低频鸣声, 以便增加传播效率, 而高频鸣声在平坦区域更为常 见[133]。依此类推, 城市中行道树冠层形成的声波反射梯度也可能迫使鸟类调整鸣声频率的带宽。
城市森林为探究生物多样性对城市化的响应机制提供了重要平台, 植物物候特征及其变化直接或间接地对鸟类鸣声多样性产生深远的影响。基于当前城市森林植物物候特征对生物多样性影响研究进展, 下面从 3 个方面概述当前研究中存在的问题, 并对未来的研究方向提出展望。
植被结构和物候等生物因素以及温度和海拔等非生物因素共同决定鸟类在不同季节的丰富性和种间竞争的变化, 即生物因素和非生物因素都参与鸟类群落的组成[113], 并对其发声产生较大的影响。对于资源依赖性物种, 植物物候可通过食物链级联效应直接调控其鸣声特征, 例如花蜜丰度及能量供给对食蜜鸟类鸣声强度的正反馈机制。广谱性类群(如杂食性鸟类)鸣声的变化则可能更多地体现为对气候因子与植物物候的平行适应。Schillé 等[134]通过被动声学监测证实, 食虫鸟类的多样性会随着气候变暖而增加。蓝山雀和大山雀也会根据即将到来的气候变化调整繁殖时间[135]。对自然栖息地的研究表明, 山斑鸠(Streptopelia orientalis)的发声模式受温度的影响显著[136]; Diepstraten 等[137]通过被动声学监测获取生物声来评估生态和人为因素对发声物种的影响, 发现鸟类发声的多样性受鸟类丰度的积极影响, 但较高的温度对其发声具有负面影响。此外, 低地雨林中鸟类丰富度及群落发声活动在一年中的表现具有明显的差异, 且这种变化与季节性降雨吻合, 歌唱的鸟类物种会随着降雨量增加而下降, 表明强降雨会限制热带雨林鸟类群落的发声活 动[138]。因此, 鸟类鸣声特征的季节性变化是植物节律与温度、降水等多因子耦合的产物, 植物物候与鸣声变化的时间同步可能源于气候共变, 而非生态互作, 无法明确地将鸟类鸣声变化归因于某一要素。未来需要进一步的实证研究, 以便全面地理解城市森林中鸟类鸣声变化的影响及机制。
多尺度框架对理解鸟类鸣声多样性的季节性变化至关重要[139]。因此, 未来可构建食物链、城市化进程和纬度梯度等多角度的城市森林植物物候与鸟类鸣声多样性的关联研究框架, 结合生态学机制与社会经济因素, 推动生物多样性保护的系统性探索, 还可为全球城市化背景下的生物多样性管理提供多尺度、跨领域的解决方案。
4.2.1 食物链角度
尽管国内外学者已初步揭示鸟类鸣声–植物以及鸟类鸣声–昆虫之间的影响机制, 但植物、消费者或传粉者(如昆虫和鸟类)对物候的不同反应会破坏生物体之间的相互作用, 可能导致物种繁殖力发生改变及食物链上的连锁反应[140], 或者消费者种群的局部灭绝[141]。另外, 城市森林植被的比例和分布具有特异化特征, 植物–鸟类网络主要由适应城市居住的鸟类组成[142]。鸟类的觅食行为与多种植物建立了复杂的相互作用网络, 植物生长和物种分布会影响以植物叶片或其他部位为食物的昆虫, 植物物候对昆虫的影响也会间接地影响食虫性或杂食性鸟类的分布。现有研究多聚焦于“植物–昆虫”或“昆虫–鸟类”二元关系, 忽视物候信号对食物链级联效应的影响。此外, 缺乏对物候变化下鸟类食性转变中缺失能量的追踪, 难以解析物候驱动的资源变化如何重塑鸟类营养生态位。因此, 未来可利用新型监测技术, 整合植物物候、昆虫和鸟类鸣声数据, 建立较高精度的营养级联数据库, 为维持城市食物链功能完整性提供科学依据, 实现生态修复型城市化目标。
4.2.2 城市化梯度
快速城市化导致城市生态环境在多方面产生与自然环境不同的差异[143], 包括夜间光照强度及城市热岛效应[144], 对城市森林植被物候造成一定的影响。Liu 等[145]从动态城乡梯度角度, 量化粤港澳大湾区植被物候对城市化的响应, 证实植被物候对动态城市化梯度的响应表现出明显的时空差异。但是, 多数研究局限于单一时间节点或空间尺度, 对“城市化进程–植物物候动态–鸟类鸣声响应”跨尺度级联效应的连续监测不足。同样, 鸣禽依赖声学信息的传播, 并根据昼夜节奏调整行为, 鸟类也会根据光强度变化来安排黎明歌唱的时间[146]。城市化下的环境噪声和光污染等干扰对城市鸟类的活动模式产生较大的影响。城市鸟类在应对不同城市化进程的城市森林栖息地物候变化中, 表达出时空尺度上的鸣声差异, 是人工环境下选择压力的表现。目前的研究中, 环境因子交互作用预测线性模型可能与真实非线性响应存在一定的偏差。此外, 城市化扩张方向的异质性也会对鸟类栖息地的连通性产生差异化的影响。因此, 未来的研究中可通过耦合环境阈值、表型适应和生态功能, 揭示城市森林中鸟类鸣声多样性的非线性响应规律, 融合环境科学、计算社会科学和生物学等前沿学科, 在城市规划中更好地平衡人类利益与生物多样性保护需求。
4.2.3 纬度梯度
纬度梯度通过光照和温度等因子, 直接调控植物物候节律, 并通过植被类型分异和种间互作作用网络间接地影响物候表达, 进而塑造鸟类鸣声多样性梯度。纬度生物相互作用假说(Latitudinal Biotic Interaction Hypothesis, LBIH)提出, 各种生物相互作用的强度由低纬度到高纬度逐步降低[147], 但其检验结果因研究对象为不同类型的交互作用或生态系统而存在差异。Zvereva 等[148]探索森林中多种相互作用的纬度模式, 证明捕食者(包括鸟类)与食草昆虫的相互作用符合纬度生物相互作用假说。但是, 鸟类对种子的取食强度未表现出明显的纬度模式, 甚至出现从低至高纬度递增取食的结果[149]。此外, 鸟类生活史特征在不同纬度梯度上表现不同, 如热带鸟类有更长的平均筑巢期[150]。鸟类多样性也存在纬度梯度, 大部分鸟类会倾向于出现在低纬度地区, 并占据这些地区可用的声学空间[151–152]。如低纬度的热带雨林植被密度较高, 可以衰减较高频率的声音[151]。高纬度(即温带地区)栖息地中, 植物物候变化更敏感, 鸟类的繁殖物候与植物物候的同步性也高于低纬度栖息地[153]。然而, 当前纬度梯度下物候与鸣声关联的研究多局限于温带自然森林, 且无法分离纬度梯度中城市化进程下的气候因子与生物因子的独立贡献。因此, 未来的研究中可沿纬度梯度布设标准化监测样带, 同步获取城市森林植物物候、鸟类鸣声及对应的气候数据, 实现跨纬度梯度对照实验; 或根据纬度带特征, 制定针对性的保护政策, 进而增强城市鸟类多样性, 改善自然保护与人类福祉之间的关系。
受成本限制, 当前的被动声学监测网络集中布设在部分区域(如自然保护区内)。尽管我国已建立全国生物多样性观测网络这类国家尺度的监测体系, 但在城市森林中开展的鸟类鸣声监测依然较少。植物物候监测技术的发展已较为成熟, 美国已建立国家生态观测站网络(National Ecological Ob-servatory Network, NEON), 用于原位观察大尺度的植物物候变化[154]。将被动声学监测技术与遥感技术相结合, 可实现动态评估大尺度区域的栖息地结构与鸟类鸣声的时空关联性。因此, 全面了解植被物候变化影响鸟类鸣声机制与未来发展趋势, 构建城市森林物候–鸟鸣声复合监测网络, 有助于了解大样地尺度的城市森林物候变化中鸟类群落的动态及其主要驱动因素, 对增强鸟类多样性及城市森林的可持续和管理至关重要[6], 可实现对城市生物多样性连续动态监测, 为未来城市生物多样性保护提供科学数据。这需要生态学、鸟类学、物候学和地理学等多领域学者开展跨学科合作, 从而明确对生物多样性有重要影响的城市森林植物物候特征和时空格局, 为探索基于自然的生物多样性保护解决方案提供更可靠的科学支撑。
参考文献
[1] Haase D, Frantzeskaki N, Elmqvist T. Ecosystem servi-ces in urban landscapes: practical applications and go-vernance implications. Ambio, 2014, 43(4): 407–412
[2] Ordóñez C, Duinker P N. Interpreting sustainability for urban forests. Sustainability, 2010, 2(6): 1510–1522
[3] Wang D, Xu P, An B, et al. Urban green infrastructure: bridging biodiversity conservation and sustainable ur-ban development through adaptive management app-roach. Frontiers in Ecology and Evolution, 2024, 12: 1440477
[4] Mitchell M G E, Devisscher T. Strong relationships between urbanization, landscape structure, and eco-system service multifunctionality in urban forest frag-ments. Landscape and Urban Planning, 2022, 228: 104548
[5] Inkiläinen E N M, McHale M R, Blank G B, et al. The role of the residential urban forest in regulating throu-ghfall: a case study in Raleigh, North Carolina, USA. Landscape and Urban Planning, 2013, 119: 91–103
[6] Canterbury G E, Martin T E, Petit D R, et al. Bird communities and habitat as ecological indicators of forest condition in regional monitoring. Conservation Biology, 2000, 14(2): 544–558
[7] Sasaki T, Imanishi J, Fukui W, et al. Fine-scale cha-racterization of bird habitat using airborne LiDAR in an urban park in Japan. Urban Forestry & Urban Gree-ning, 2016, 17: 16–22
[8] de Groot M, Flajšman K, Mihelič T, et al. Green space area and type affect bird communities in a South-eastern European city. Urban Forestry & Urban Gree-ning, 2021, 63: 127212
[9] Xu X, Xie Y, Qi K, et al. Detecting the response of bird communities and biodiversity to habitat loss and frag-mentation due to urbanization. Science of the Total Environment, 2018, 624: 1561–1576
[10] Slater P J B. Fifty years of bird song research: a case study in animal behaviour. Animal Behaviour, 2003, 65(4): 633–639
[11] Baker M C, Bjerke T K, Lampe H, et al. Sexual res-ponse of female great tits to variation in size of males’ song repertoires. The American Naturalist, 1986, 128 (4): 491–498
[12] Nowicki S, Searcy W A. Song and mate choice in birds: how the development of behavior helps us understand function. The Auk, 2005, 122(1): 1–14
[13] Catano C P, Fristoe T S, LaManna J A, et al. Local species diversity, β-diversity and climate influence the regional stability of bird biomass across North Ame-rica. Proceedings of the Royal Society B: Biological Sciences, 2020, 287: 20192520
[14] Budka M, Gazda-Szypulski G, Muszyńska A, et al. Acoustic indices enable the discrimination of tem-perate forest types and better predict differences in bird species composition than in bird species richness. Environmental and Sustainability Indicators, 2024, 24: 100529
[15] Dong Y, Cai Y, Li C, et al. Vertical thermal environ-ment of subtropical broad-leaved urban forests and the influence of canopy structure. Building and Environ-ment, 2022, 224: 109521
[16] Cabral I, Keim J, Engelmann R, et al. Ecosystem services of allotment and community gardens: a Leip-zig, Germany case study. Urban Forestry & Urban Greening, 2017, 23: 44–53
[17] 王钊, 彭艳, 权文婷, 等. 秦岭森林物候时空分布特征及对水热条件的响应. 干旱区地理, 2019, 42 (5): 1048–1058
[18] Zipper S C, Schatz J, Singh A, et al. Urban heat island impacts on plant phenology: intra-urban variability and response to land cover. Environmental Research Let-ters, 2016, 11(5): 54023
[19] Luo Z, Sun O J, Ge Q, et al. Phenological responses of plants to climate change in an urban environment. Ecological Research, 2007, 22(3): 507–514
[20] Jochner S, Menzel A. Urban phenological studies — past, present, future. Environmental Pollution, 2015, 203: 250–261
[21] Anand P, Mina U, Khare M, et al. Air pollution and plant health response-current status and future direc-tions. Atmospheric Pollution Research, 2022, 13(8): 101508
[22] Mendes R S, de Araújo-Hoffmann F P. Nectar plants visited by hummingbirds in an urban area of southern Brazil. Urban Ecosystems, 2025, 28(1): 47
[23] Yang J, Luo X, Jin C, et al. Spatiotemporal patterns of vegetation phenology along the urban–rural gradient in Coastal Dalian, China. Urban Forestry & Urban Gree-ning, 2020, 54: 126784
[24] Marchenko A A, Ivanov A V. Effects of temperature variations and urban heat island on the seasonal deve-lopment of woody plants in the south of Primorsky Krai. Contemporary Problems of Ecology, 2024, 17(7): 1099–1106
[25] Neil K, Wu J. Effects of urbanization on plant flo-wering phenology: a review. Urban Ecosystems, 2006, 9(3): 243–257
[26] Du H, Wang M, Liu Y, et al. Responses of autumn vegetation phenology to climate change and urbanize-tion at northern middle and high latitudes. International Journal of Applied Earth Observation and Geoinfor-mation, 2022, 115: 103086
[27] Galán Díaz J, Gutiérrez-Bustillo A M, Rojo J. Influ-ence of urbanisation on the phenology of evergreen coniferous and deciduous broadleaf trees in Madrid (Spain). Landscape and Urban Planning, 2023, 235: 104760
[28] Park D S, Breckheimer I, Williams A C, et al. Herba-rium specimens reveal substantial and unexpected va-riation in phenological sensitivity across the eastern United States. Philosophical Transactions of the Ro- yal Society B: Biological Sciences, 2019, 374(1763): 20170394
[29] Jeong J H, Ho C H, Linderholm H W, et al. Impact of urban warming on earlier spring flowering in Korea. International Journal of Climatology, 2011, 31(10): 1488–1497
[30] Chibesa M, Downs C T. Factors determining the occu-pancy of trumpeter hornbills in urban-forest mosaics of KwaZulu-Natal, South Africa. Urban Ecosystems, 2017, 20(5): 1027–1034
[31] Gonçalves da Silva B, Koch I, Piratelli A J. Fruit and flower availability affect bird assemblages across two successional stages in the Atlantic Forest. Studies on Neotropical Fauna and Environment, 2020, 55(3): 203– 215
[32] Almeida B A, Bochio G M, Calsavara L C, et al. Seasonality in niche occupation revealed through bird community functional structure in the southern Atlan-tic rainforest. Ibis, 2023, 165(3): 986–997
[33] Tarjuelo R, Benítez-López A, Casas F, et al. Living in seasonally dynamic farmland: the role of natural and semi-natural habitats in the movements and habitat selection of a declining bird. Biological Conservation, 2020, 251: 108794
[34] 郝泽周, 张承云, 李乐, 等. 城市鸟类多样性被动声学监测与评价技术应用. 生物多样性, 2024, 32 (10): 17–23
[35] Youngflesh C, Montgomery G A, Saracco J F, et al. Demographic consequences of phenological asyn-chrony for North American songbirds. Proceedings of the National Academy of Sciences, 2023, 120(28): e2073006176
[36] Wei J, Xu F, Cole E F, et al. Spatially heterogeneous shifts in vegetation phenology induced by climate change threaten the integrity of the avian migration network. Global Change Biology, 2024, 30(1): e17148
[37] Kavana D J, Mbije N, Sirilo T M, et al. The spatio‐temporal influences of habitat heterogeneity on the community structure of avian feeding guilds in human‐dominated landscapes of the East African miombo woodlands. African Journal of Ecology, 2024, 62(1): e13237
[38] MARLER P. Bird calls: their potential for behavioral neurobiology. Annals of the New York Academy of Sciences, 2004, 1016(1): 31–44
[39] Eldridge A, Guyot P, Moscoso P, et al. Sounding out ecoacoustic metrics: avian species richness is predicted by acoustic indices in temperate but not tropical habitats. Ecological Indicators, 2018, 95: 939–952
[40] Yang Y, Chen Y, Ye Z, et al. Springtime spatio-temporal distribution of bird diversity in urban parks based on acoustic indices. Global Ecology and Conservation, 2024, 53: e02995
[41] Bradfer Lawrence T, Desjonqueres C, Eldridge A, et al. Using acoustic indices in ecology: guidance on study design, analyses and interpretation. Methods in Eco-logy and Evolution, 2023, 14(9): 2192–2204
[42] Shamon H, Paraskevopoulou Z, Kitzes J, et al. Using ecoacoustics metrices to track grassland bird rich- ness across landscape gradients. Ecological Indicators, 2021, 120: 106928
[43] Alcocer I, Lima H, Sugai L S M, et al. Acoustic indices as proxies for biodiversity: a meta‐analysis. Biological Reviews, 2022, 97(6): 2209–2236
[44] Buxton R T, Brown E, Sharman L, et al. Using bioacou-stics to examine shifts in songbird phenology. Ecology and Evolution, 2016, 6(14): 4697–4710
[45] Atemasov A, Atemasova T. Impact of stand variables on characteristics of avian soundscape in common oak (Quercus robur L.) forests. Forestry Studies, 2019, 70 (1): 68–79
[46] Shaw T, Hedes R, Sandstrom A, et al. Hybrid bioacou-stic and ecoacoustic analyses provide new links bet-ween bird assemblages and habitat quality in a winter boreal forest. Environmental and Sustainability Indica-tors, 2021, 11: 100141
[47] Sueur J, Pavoine S, Hamerlynck O, et al. Rapid acou-stic survey for biodiversity appraisal. PLOS ONE, 2008, 3(12): e4065
[48] Pieretti N, Farina A, Morri D. A new methodology to infer the singing activity of an avian community: the acoustic complexity index (ACI). Ecological Indica-tors, 2011, 11(3): 868–873
[49] Villanueva-Rivera L J, Pijanowski B C, Doucette J, et al. A primer of acoustic analysis for landscape ecolo-gists. Landscape Ecology, 2011, 26(9): 1233–1246
[50] Boelman N T, Asner G P, Hart P J, et al. Multi‐trophic invasion resistance in Hawaii: bioacoustics, field sur-veys, and airborne remote sensing. Ecological Appli-cations, 2007, 17(8): 2137–2144
[51] Kasten E P, Gage S H, Fox J, et al. The remote environmental assessment laboratory’s acoustic libra-ry: an archive for studying soundscape ecology. Eco-logical Informatics, 2012, 12: 50–67
[52] Jeong J, Park C. Urban forest indicator assessment for nature-based solutions to connect biodiversity and people. Ecological Indicators, 2024, 169: 112843
[53] Sierro J, de Kort S R, Hartley I R. Sexual selection for both diversity and repetition in birdsong. Nature Com-munications, 2023, 14(1): 3600
[54] Boncoraglio G, Saino N. Habitat structure and the evolution of bird song: a meta‐analysis of the eviden-ce for the acoustic adaptation hypothesis. Functional Ecology, 2007, 21(1): 134–142
[55] Dröge S, Martin D A, Andriafanomezantsoa R, et al. Listening to a changing landscape: acoustic indices reflect bird species richness and plot-scale vegetation structure across different land-use types in north-eastern Madagascar. Ecological Indicators, 2021, 120: 106929
[56] Gaspar L P, D. A. Scarpelli M, Oliveira E G, et al. Predicting bird diversity through acoustic indices within the Atlantic Forest biodiversity hotspot. Fron-tiers in Remote Sensing, 2023, 4: 1283719
[57] Newell F L, Sheehan J, Wood P B, et al. Comparison of point counts and territory mapping for detecting effects of forest management on songbirds. Journal of Field Ornithology, 2013, 84(3): 270–286
[58] Wang Q, Jin P, Wu Y, et al. Infrared image enhance-ment: a review. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2025, 18: 3281–3299
[59] Gibb R, Browning E, Glover Kapfer P, et al. Emerging opportunities and challenges for passive acoustics in ecological assessment and monitoring. Methods in Ecology and Evolution, 2019, 10(2): 169–185
[60] Dziak R, Matsumoto H, Haver S, et al. PMEL passive acoustics research: quantifying the ocean soundscape from whales to wave energy. Oceanography, 2023: 36 (2/3): 196–205
[61] Hao Z, Zhang C, Li L, et al. Anthropogenic noise and habitat structure shaping dominant frequency of bird sounds along urban gradients. iScience, 2024, 27(2): 109056
[62] Alberton B, Torres R D S, Cancian L F, et al. Intro-ducing digital cameras to monitor plant phenology in the tropics: applications for conservation. Perspectives in Ecology and Conservation, 2017, 15(2): 82–90
[63] de Almeida D R A, Vedovato L B, Fuza M, et al. Remote sensing approaches to monitor tropical forest restoration: current methods and future possibilities. Journal of Applied Ecology, 2025, 62(2): 188–206
[64] Gong Z, Ge W, Guo J, et al. Satellite remote sensing of vegetation phenology: progress, challenges, and oppor-tunities. ISPRS Journal of Photogrammetry and Re-mote Sensing, 2024, 217: 149–164
[65] Girma Z, Mamo Y, Mengesha G, et al. Seasonal abun-dance and habitat use of bird species in and around Wondo Genet Forest, south‐central Ethiopia. Ecology and Evolution, 2017, 7(10): 3397–3405
[66] Vitorino B D, Frota A V B D, Maruyama P K. Ecological determinants of interactions as key when planning pollinator-friendly urban greening: a plant-hummingbird network example. Urban Forestry & Urban Greening, 2021, 64: 127298
[67] Peters V E, Mordecai R, Ronald Carroll C, et al. Bird community response to fruit energy. Journal of Animal Ecology, 2010, 79(4): 824–835
[68] French K, Major R, Hely K. Use of native and exotic garden plants by suburban nectarivorous birds. Biolo-gical Conservation, 2005, 121(4): 545–559
[69] Davis A, Major R E, Taylor C E. Do trees flower longer in the city? A comparison of flowering eucalyptus trees in streets, remnants and continuous forest and their association with nectarivorous birds. Urban Ecosy-stems, 2016, 19(2): 735–747
[70] Rodrigues L, Araujo A. The hummingbird community and their floral resources in an urban forest remnant in Brazil. Brazilian Journal of Biology, 2011, 71(3): 611–622
[71] Gray E R, van Heezik Y. Exotic trees can sustain native birds in urban woodlands. Urban Ecosystems, 2016, 19(1): 315–329
[72] Anselmo P A, Cardoso J C F, Siqueira P R, et al. Non-native plants and illegitimate interactions are highly relevant for supporting hummingbird pollinators in the urban environment. Urban Forestry & Urban Greening, 2023, 86: 128025
[73] Maglianesi M A, Maruyama P K, Temeles E J, et al. Behavioural and morphological traits influence sex‐specific floral resource use by hummingbirds. Journal of Animal Ecology, 2022, 91(11): 2171–2180
[74] Ramírez Burbano M B, Amorim F W, Torres González A M, et al. Nectar provision attracts hummingbirds and connects interaction networks across habitats. IBIS, 2022, 164(1): 88–101
[75] Bosenbecker C, Anselmo P A, Fonseca T M, et al. Consistent generalization of plant-hummingbird net-works despite increasing vegetation cover across a tropical urban landscape. Urban Forestry & Urban Greening, 2024, 101: 128498
[76] Deshpande P, Johansson N, Kluen E, et al. Changing bird migration patterns have potential to enhance dispersal of alien plants from urban centres. Global Change Biology, 2024, 30(11): e17572
[77] Zhang M, Lu C, Han Q, et al. Structure and charac-teristics of plant-frugivore network in an urban park: a case study in Nanjing Botanical Garden Mem Sun Yat-Sen. Diversity, 2022, 14(2): 71
[78] Khan A U, Dad F P, Hasnain R, et al. Foraging routine of two common urban birds on berries of exotic Livi-stona chinensis: a winter supplement in an urban land-scape. Sustainability, 2023, 15(19): 14521
[79] Seress G, Sándor K, Evans K L, et al. Food availability limits avian reproduction in the city: an experimental study on great tits Parus major. Journal of Animal Ecology, 2020, 89(7): 1570–1580
[80] Raley C M, Anderson S H. Availability and use of arthropod food resources by Wilson’s warblers and Lincoln’s sparrows in southeastern Wyoming. The Condor, 1990, 92(1): 141–150
[81] Seress G, Hammer T, Bókony V, et al. Impact of urbanization on abundance and phenology of caterpil-lars and consequences for breeding in an insectivorous bird. Ecological Applications, 2018, 28(5): 1143–1156
[82] Vaugoyeau M, Adriaensen F, Artemyev A, et al. Inter-specific variation in the relationship between clutch size, laying date and intensity of urbanization in four species of hole‐nesting birds. Ecology and Evolution, 2016, 6(16): 5907–5920
[83] Slabbekoorn H. Songs of the city: noise-dependent spectral plasticity in the acoustic phenotype of urban birds. Animal Behaviour, 2013, 85(5): 1089–1099
[84] Peng L, Liu Q, Wang Q, et al. Effects of urbanization and vegetation on bird diversity in a megacity of central China. Biological Conservation, 2024, 297: 110718
[85] Snyder K, Sellers M, Creanza N. Cultural shifts after punctuated environmental stress: a study of song distri-butions in Dark-eyed Junco and Song Sparrow popula-tions. Journal of Field Ornithology, 2024, 95(2): art3
[86] Kharouba H M, Wolkovich E M. Lack of evidence for the match‐mismatch hypothesis across terrestrial tro-phic interactions. Ecology Letters, 2023, 26(6): 955–964
[87] Slagsvold T, Eriksen A, de Ayala R M, et al. Postfled-ging movements in birds: do tit families track environ-mental phenology?. The Auk, 2013, 130(1): 36–45
[88] Hällfors M H, Antão L H, Itter M, et al. Shifts in timing and duration of breeding for 73 boreal bird species over four decades. Proceedings of the National Academy of Sciences, 2020, 117(31): 18557–18565
[89] Blinkova O, Shupova T. Bird communities and vegeta-tion composition in the urban forest ecosystem: corre-lations and comparisons of diversity indices. Ekológia (Bratislava), 2017, 36(4): 366–387
[90] Rosenberg K V, Dokter A M, Blancher P J, et al. Dec-line of the North American avifauna. Science, 2019, 366: 120–124
[91] Melles S S G A. Urban bird diversity and landscape complexity: species–environment associations along a multiscale habitat gradient. Conservation Ecology, 2003, 7(1): 5
[92] Gumede S T, Ehlers Smith D A, Ngcobo S P, et al. The influence of forest characteristics on avian species richness and functional diversity in Southern Mistbelt Forests of South Africa. Global Ecology and Conser-vation, 2022, 34: e02047
[93] Monniez E, Jiguet F, Vignal C, et al. Differential effects of anthropogenic noise and vegetation cover on the breeding phenology and success of two urban passerines. Frontiers in Ecology and Evolution, 2022, 10: 1058584
[94] Martin T E, Roper J J. Nest predation and nest-site selection of a western population of the hermit thrush. The Condor, 1988, 90(1): 51–57
[95] Jara R F, Crego R D, Samuel M D, et al. Nest-site selection and breeding success of passerines in the world’s southernmost forests. PeerJ, 2020, 8: e9892
[96] Metcalfe N B. The effects of habitat on the vigilance of shorebirds: is visibility important?. Animal Beha-viour, 1984, 32(4): 981–985
[97] Carey H V, Moore P. Foraging and predation risk in yellow-bellied marmots. American Midland Naturalist, 1986, 116(2): 267
[98] Shaw T, Scherer-Lorenzen M, Müller S. Forest struc-tural heterogeneity positively affects bird richness and acoustic diversity in a temperate, central European forest. Frontiers in Ecology and Evolution, 2024, 12: 1387879
[99] Smith T B, Harrigan R J, Kirschel A N G, et al. Predic-ting bird song from space. Evolutionary Applications, 2013, 6(6): 865–874
[100] Blumenrath S, Dabelsteen T. Degradation of great tit (Parus major) song before and after foliation: implica-tions for vocal communication in a deciduous forest. Behaviour, 2004, 141(8): 935–958
[101] Gaudon J M, McTavish M J, Hamberg J, et al. Noise attenuation varies by interactions of land cover and season in an urban/peri-urban landscape. Urban Ecosy-stems, 2022, 25(3): 811–818
[102] Liu J, Liu F, Tong H, et al. Differences in soundscape perception of plants space in urban green space and the influence of factors: the case of Fuzhou, China. Fore-sts, 2024, 15(3): 417
[103] Hao Z, Zhang C, Li L, et al. Can urban forests provide acoustic refuges for birds? Investigating the influence of vegetation structure and anthropogenic noise on bird sound diversity. Journal of Forestry Research, 2024, 35(1): 33
[104] Han Q, Keeffe G. Promoting climate-driven forest mig-ration through large-scale urban afforestation. Land-scape and Urban Planning, 2021, 212: 104124
[105] Lee C, Park C R. An increase in song pitch of eastern great tits (Parus minor) in response to urban noise at Seoul, Korea. Urban Ecosystems, 2019, 22(2): 227–233
[106] Winandy G S M, Félix R P, Sacramento R A, et al. Urban noise restricts song frequency bandwidth and syllable diversity in bananaquits: increasing audibility at the expense of signal quality. Frontiers in Ecology and Evolution, 2021, 9: 570420
[107] Luther D A, Danner R, Danner J, et al. The relative response of songbirds to shifts in song amplitude and song minimum frequency. Behavioral Ecology, 2016: arw172
[108] Xu W, Yu J, Huang P, et al. Relationship between vegetation habitats and bird communities in urban mountain parks. Animals, 2022, 12(18): 2470
[109] Reif J, Jiran M, Reifová R, et al. Interspecific territo-riality in two songbird species: potential role of song convergence in male aggressive interactions. Animal Behaviour, 2015, 104: 131–136
[110] Yang Y, Ye Z, Zhang Z, et al. Investigating the drivers of temporal and spatial dynamics in urban forest bird acoustic patterns. Journal of Environmental Manage-ment, 2025, 376: 124554
[111] Pfeifer R, Stadler J, Roland B. Is the seasonal variation of abundance and species richness in birds explained by energy availability?. Acta Ornithologica, 2017, 52 (2): 167–178
[112] Bennett J M, Clarke R H, Thomson J R, et al. Variation in abundance of nectarivorous birds: Does a compe-titive despot interfere with flower tracking?. Journal of Animal Ecology, 2014, 83(6): 1531–1541
[113] Seoane J, Villén Pérez S, Carrascal L M. Environ-mental determinants of seasonal changes in bird diver-sity of Mediterranean oakwoods. Ecological Research, 2013, 28(3): 435–445
[114] Møller A P, Czeszczewik D, Flensted-Jensen E, et al. Abundance of insects and aerial insectivorous birds in relation to pesticide and fertilizer use. Avian Research, 2021, 12(1): 43
[115] Naef Daenzer B, Keller L F. The foraging performance of great and blue tits (Parus major and P. caeruleus) in relation to caterpillar development, and its consequ-ences for nestling growth and fledging weight. Journal of Animal Ecology, 1999, 68(4): 708–718
[116] Philpott S M, Soong O, Lowenstein J H, et al. Func-tional richness and ecosystem services: bird preda- tion on arthropods in tropical agroecosystems. Eco-logical Applications, 2009, 19(7): 1858–1867
[117] Krause B L. The niche hypothesis: a virtual symphony of animal sounds, the origins of musical expression and the health of habitats. The Soundscape Newsletter, 1993, 6(5): 6–10
[118] Xing X Y, Alström P, Yang X J, et al. Recent northward range expansion promotes song evolution in a passe-rine bird, the Light‐vented Bulbul. Journal of Evolu-tionary Biology, 2013, 26(4): 867–877
[119] Kath J, Maron M, Dunn P K. Interspecific competition and small bird diversity in an urbanizing landscape. Landscape and Urban Planning, 2009, 92(2): 72–79
[120] Samplonius J M, Both C. Climate change may affect fatal competition between two bird species. Current Biology, 2019, 29(2): 327–331
[121] Thomas D W, Bourgault P, Shipley B, et al. Context-dependent changes in the weighting of environmental cues that initiate breeding in a temperate passerine, the corsican blue tit (Cyanistes caeruleus). The Auk, 2010, 127(1): 129–139
[122] Lakatos T, Chamberlain D E, Garamszegi L Z, et al. No place for ground-dwellers in cities: a meta-analysis on bird functional traits. Global Ecology and Conserva-tion, 2022, 38: e02217
[123] Husby M, Slagsvold T. The number of syllables per phrase in great tit (Parus major) song decreases in strong anthropogenic noise and at northern latitudes. Ornis Norvegica, 2023, 46: 28–42
[124] Morton E S. Ecological sources of selection on avian sounds. The American Naturalist, 1975, 109: 17–34
[125] Fuller R A, Warren P H, Gaston K J. Daytime noise predicts nocturnal singing in urban robins. Biology Letters, 2007, 3(4): 368–370
[126] Brumm H. The impact of environmental noise on song amplitude in a territorial bird. Journal of Animal Eco-logy, 2004, 73(3): 434–440
[127] Charmantier A, Gienapp P. Climate change and timing of avian breeding and migration: evolutionary versus plastic changes. Evolutionary Applications, 2014, 7(1): 15–28
[128] Narango D L, Rodewald A D. Urban-associated drivers of song variation along a rural–urban gradient. Beha-vioral Ecology, 2016, 27(2): 608–616
[129] Møller A P, Díaz M, Grim T, et al. Effects of urbani-zation on bird phenology: a continental study of paired urban and rural populations. Climate Research, 2015, 66(3): 185–199
[130] Kucera A J, Smith M C, Wagnon G S, et al. Group size and singing phenology of northern cardinals (Cardina-lis cardinalis) varies between urban and rural habitats. The Southwestern Naturalist, 2019, 64(1): 56
[131] Zhu X, Lau S, Lu Z, et al. Enhancement of sound absorption via vegetation with a metasurface substrate. Applied Acoustics, 2020, 165: 107309
[132] Xie S, Han B, Zhou W, et al. Spatio-temporal variation in bird assemblages in a subtropical urban ecosystem. Diversity, 2022, 14(5): 341
[133] He X, Deng Y, Dong A, et al. The relationship between acoustic indices, vegetation, and topographic charac-teristics is spatially dependent in a tropical forest in southwestern China. Ecological Indicators, 2022, 142: 109229
[134] Schillé L, Valdés Correcher E, Archaux F, et al. De-composing drivers in avian insectivory: large‐scale effects of climate, habitat and bird diversity. Journal of Biogeography, 2024, 51(6): 1079–1094
[135] Glądalski M, Bańbura M, Kaliński A, et al. Effects of extreme thermal conditions on plasticity in breeding phenology and double-broodedness of Great Tits and Blue Tits in central Poland in 2013 and 2014. Inter-national Journal of Biometeorology, 2016, 60(11): 1795–1800
[136] Wang M, Mei J, Liu F. Temporal acoustic patterns of the oriental turtle dove in a subtropical forest in China. Diversity, 2022, 14(12): 1043
[137] Diepstraten J, Willie J. Assessing the structure and drivers of biological sounds along a disturbance gra-dient. Global Ecology and Conservation, 2021, 31: e01819
[138] Vokurková J, Motombi F N, Ferenc M, et al. Seasona-lity of vocal activity of a bird community in an Afro-tropical lowland rain forest. Journal of Tropical Eco-logy, 2018, 34(1): 53–64
[139] Leveau L M, Bocelli L, Quesada-Acuña S G, et al. Drivers of seasonal change of avian communities in urban parks and cemeteries of latin america. Animals, 2024, 14(24): 3564
[140] Strode P K. Implications of climate change for north American wood warblers (Parulidae). Global Change Biology, 2003, 9(8): 1137–1144
[141] Singer M C, Parmesan C. Phenological asynchrony between herbivorous insects and their hosts: signal of climate change or pre-existing adaptive strategy? Philosophical Transactions of the Royal Society B: Biological Sciences, 2010, 365(1555): 3161–3176
[142] Schneiberg I, Boscolo D, Devoto M, et al. Urbanization homogenizes the interactions of plant-frugivore bird networks. Urban Ecosystems, 2020, 23(3): 457–470
[143] Paolini L, Aráoz E, Gioia A, et al. Vegetation producti-vity trends in response to urban dynamics. Urban Forestry & Urban Greening, 2016, 17: 211–216
[144] Wang L, De Boeck H J, Chen L, et al. Urban warming increases the temperature sensitivity of spring vegeta-tion phenology at 292 cities across china. Science of the Total Environment, 2022, 834: 155154
[145] Liu Z, Zhou Y, Feng Z. Response of vegetation phe-nology to urbanization in urban agglomeration areas: a dynamic urban–rural gradient perspective. Science of the Total Environment, 2023, 864: 161109
[146] Nordt A, Klenke R. Sleepless in town — drivers of the temporal shift in dawn song in urban European blackbirds. PLOS ONE, 2013, 8(8): e71476
[147] Schemske D W, Mittelbach G G, Cornell H V, et al. Is there a latitudinal gradient in the importance of biotic interactions?. Annual Review of Ecology, Evolution, and Systematics, 2009, 40(1): 245–269
[148] Zvereva E L, Zverev V, Kozlov M V. Predation and parasitism on herbivorous insects change in opposite directions in a latitudinal gradient crossing a boreal forest zone. Journal of Animal Ecology, 2020, 89(12): 2946–2957
[149] Zvereva E L, Castagneyrol B, Cornelissen T, et al. Opposite latitudinal patterns for bird and arthropod predation revealed in experiments with differently co-lored artificial prey. Ecology and Evolution, 2019, 9 (24): 14273–14285
[150] Freeman B G, Scholer M N, Boehm M M A, et al. Adaptation and latitudinal gradients in species interac-tions: nest predation in birds. The American Naturalist, 2020, 196(6): E160–E166
[151] Weir J T, Wheatcroft D J, Price T D. The role of ecological constraint in driving the evolution of avian song frequency across a latitudinal gradient. Evolution, 2012, 66(9): 2773–2783
[152] Singh P, Price T D. Causes of the latitudinal gradient in birdsong complexity assessed from geographical va-riation within two Himalayan warbler species. IBIS, 2015, 157(3): 511–527
[153] Silva-Jr E F, Diniz P, Macedo R H. Song varies with latitude, climate, and species richness in a neotropical bird. Behavioral Ecology, 2022, 33(1): 87–100
[154] Elmendorf S C, Jones K D, Cook B I, et al. The plant phenology monitoring design for the national eco-logical observatory network. Ecosphere, 2016, 7(4): e01303
Review on the Impact of Plant Phenological Changes on Bird Sound Diversity in Urban Forests
Abstract A systematic review of the literature on the characteristics of plant phenology and its drivers in urban forests was conducted to reveal the impact of plant phenology on bird sound diversity under urbanization and to explore the ecological association therein. The relationship between plant phenology and the spatiotemporal patterns of bird sounds was analyzed to identify the mechanisms through which vegetation dynamics shape bird sound diversity in urban forests. The main findings were as follows. 1) Urban forest plant phenology directly or indirectly affects bird sound diversity by altering food resource dynamics, habitat characteristics and interspecific competition. 2) Urban forest birds adapt their phenotypic plasticity through vocal behaviors to cope with phenology-driven resource competition. Future studies on the effects of urban forest plant phenology on bird sound diversity should focus on seasonal variations. The application of emerging monitoring technologies and the construction of a compo-site phenology-acoustic monitoring network are expected to promote the in-depth analysis of the multidimensional mechanisms between plant phenology and biodiversity in urban forests. Multi-perspective and cross-disciplinary co-operation should be strengthened to address the complex challenges of biodiversity conservation during urbanization.
Key words urban forest; plant phenology; bird; sound diversity; response mechanisms; biodiversity conservation