Comparison and Application of Survey Methods of Bird Diversity
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摘要: 在鸟类多样性研究中,种类和数量是评估物种受胁状况、种群动态、群落结构特征、生态系统功能和栖息地质量的常用参数。受到鸟类生态类型多样、行为特征和生活史差异较大等因素的影响,野外调查结果与鸟类多样性的实际情况存在一定偏差。本文整理了7种常见鸟类多样性调查方法的概念和调查统计指标,包括标图法、直接计数法、样线法、样点法、红外相机调查法、网捕法和鸣声调查法,并对比了各方法的优缺点,以及在不同生境、不同鸟类类群间的适用性和生态假设条件。建议根据研究目的和对象选择合适的调查方法,并多方法综合使用,如样点法和样线法的适用范围最广,但活动隐蔽或数量稀少的鸟类需借助网捕、红外相机或鸣声法补充调查。其次提出传统方法与新技术的结合使用,如水鸟调查中结合无人机和地面直接计数,雉科鸟类调查中结合红外相机和标图法,将有效提高调查效率和准确度。最后强调鸟类多样性调查方法的标准化对今后我国鸟类学群落理论研究、大尺度多样性监测网络与评价体系建设、区域保护策略制定具有重要推动作用。Abstract: Bird species richness and population abundance have a wide applications in assessing species threatened status, population dynamics, community structure characteristics, ecosystem function and habitat quality. Due to the diversity of ecological types and the wide variation in behavioural characteristics and life histories, there are some deviations between field survey results and the actual situation of bird diversity. This study compiles the concepts and statistical indicators of seven bird survey methods, including territory mapping, individual counts, line transects, point transects, camera trapping, mist netting and vocalization surveying. By comparing the advantages and applicability of each method in different habitats and different bird groups, we suggest that the optimal method should be selected according to the research purpose and object, and multiple methods should be used in combination. For example, the line transects and point transects are the most widely applicable, while mist netting, camera trapping and vocalization surveying are necessary for birds with hidden habits or sparse population. Secondly, the combination of traditional methods with new technologies will effectively improve the efficiency and accuracy of bird survey. Such as the combination of unmanned aerial vehicles and aggregating counts in waterbird surveying, and the combination of camera trapping and territory mapping in pheasant surveying. Finally, we prospect that the standardization of bird survey methods will play an important role in promoting the basic theoretical research of ornithological community theory, the construction of large-scale monitoring network and evaluation system, and the formulation of regional conservation strategies in China.
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Key words:
- birds /
- stratified sampling /
- biodiversity monitoring /
- population abundance
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附录 Supplementary Material 1 鸟类多样性调查方法示意图、野外工作流程与数量统计指标
1. Schematic diagram, field work flow and statistical indicators of bird survey methods
调查方法
Methods示意图
Schematic diagram野外工作流程
Field work flow数量统计指标
Statistical indicators标图法
Territory mapping1.根据调查对象和栖息地确定样地面积、调查路线、时间和次数,按比例制作样地图;
2.在样地中调查鸟类,将所有发现的同种鸟类及其痕迹、活动,特别是求偶、争斗、巢址等与领域相关的信息,准确定位标记到样地图中,作为调查图(visit map) ,每次调查1张;
3.同种鸟类的每次调查的信息都转换记录至其种类图(species map) ,每种1张;
4.结合种类图中多次调查所记录的位点及其信息(如▲代表鸟类个体,■代表巢址,∽代表领域争斗行为),圈出互不重叠的位点群,为大致的鸟类领域边界。$ D = \dfrac{{c \cdot n}}{s} $
D为种群密度,c为总位点群数,n为每一位点群内平均个体数,s为样地面积直接计数法
Individual counts
直接计数法:
直接数出集群个体数量
直接辨认种类并计算种群数量 集团统计法:
设定包含n个个体的小集团,通过数小集团数量从而估计总集群数量
(图中以10个一组为例,共6组,即估算该集群包含60个个体)样线法
Line transects1.系统或分层随机选择调查样线,充分代表样地;
2.按需设置调查重复次数、前进速度、样线长度l和调查宽度w等;
3.根据上述要求,沿样线匀速前进,按距离带(如0<w1<25 m,w2>25 m)调查记录鸟类个体(①和③位于调查带w1,②和④位于w2) ;或测定所有个体至样线的实际距离h;
4.一定时间间隔后重复调查,分析数据。
$ D = \dfrac{n}{{{\text{2}} \cdot l \cdot w}} $
D为种群密度,n为调查记录鸟类个体数,l为样线长度,w为单侧截线宽度
以单位时间或路线的遇见率代表相对数量 样点法
Point transects1.系统或分层随机选择调查样点,充分代表样地;
2.按需设置样点数量、调查持续时间、重复次数和调查半径r 等;
3.调查者静止在样点中心p,按距离区(如0<r1<50 m,r2>50 m)调查记录鸟类个体(①和②位于调查区r1,③和④位于r2) ;或测定所有个体至样点中心的实际距离h;
4.一定时间间隔后重复调查,分析数据。
$ D = \dfrac{n}{{3.14{r^{\text{2}}}}} $
D为种群密度,n为调查记录鸟类个体数,r为截线半径
以每个样点的平均个体数或出现频度代表相对数量 红外相机
调查法
Camera trapping1.根据调查目的和需要选择红外相机布设点;
2.设置红外相机,自动监测前方一定距离的区域,当有野生动物出现会触发设备,拍摄照片与动态影像;
3.回收红外相机监测数据与处理分析。相对多度指数:
$ {\text{RAI}} = \dfrac{{\displaystyle\sum\nolimits_{i = 1} {{N_i}} }}{{\displaystyle\sum\nolimits_{i = 1} {Trapda{y_i}} }} \times 100 $
Trapdayi为相机位点i的拍摄天数,Ni为相机位点i拍摄的某一物种的有效照片数相对丰富度指数:
$ {\text{SA}}{{\text{I}}_{}} = \dfrac{{{A_i}}}{N} \times 100 $
Ai为目标物种的独立有效照片数,N为所有物种的独立有效照片数网捕法
Mist netting1.根据研究目的确定雾网架设位置、时长、类型、调查次数等,向相关管理部门提出申请并获取批准;
2.清理网场,架设雾网(森林鸟类群落调查中网场通常高约3 m,长13~15 m,宽1~2 m;雾网规格一般长12 m,高2.5 m,网眼36 mm) ;
3.每隔一段时间检查、记录上网鸟类。
标记重捕模型:
$ P = \dfrac{{a \cdot n}}{r} $
P为种群数量,a为标记个体数量,n为第2次捕获个体总数,r为第2次捕获标记个体数
以网捕率表示相对种群数量 鸣声调查法
Vocalization surveying
鸣声回放法:
播放目标物种鸣声,吸引其作出回应或接近声源等反应
协助鸟类数量调查
鸣声计数法:
1.通过主、被动的录音设备采集鸟类鸣声;
2.使用相关的电脑软件分析声音特征,绘制声谱图(sound spectrogram)
量化分析鸣声特点差异或声音指数。
分析鸣声声谱图区分物种,或使用生物声学指数等声音指数反映鸟类多样性 2 不同鸟类调查方法的适用性与生态假设条件
2. Ecological applicability and assumptions of each bird survey methods
调查方法
Methods适宜生境
Habitat适宜鸟种
Bird characteristics缺点
Insufficient生态假设条件
Ecological assumptions标图法
Territory mapping平坦生境,植被稀疏 繁殖期间领域性行为明显 人力成本高,效率低 ①繁殖期间鸟类都具有领域性,且总在领域内活动;
②鸟类成对,每一领域内具有2个个体;
③样地内所有鸟类个体的发现率相同,能被正确发现和记录;
④调查结果不受调查人员活动、植被结构等因素影响;
⑤除了要求最小面积外,面积因素对结果无影响。直接计数法
Individual counts宽阔生境,遮挡少 小范围集群活动 估算数量受调查者主观影响 ①调查者能正确识别鸟类种类并准确数出集群数量;
②一定时间、范围内,同种鸟类的大部分个体集群活动,集群大小反映其种群数量。样线法
Line transects可视距离高,植被稀疏 较易发现,样地中分布密度低 对珍稀、罕见鸟种的调查效果较差 ①完整记录调查范围内的鸟类;
②鸟类不因调查者的存在而进出调查范围;
③所有发现的个体都相互独立,未被重复记录;
④准确测定鸟类个体至样线(样点)的距离;
⑤每次鸟类调查相互独立;
⑥正确鉴别所有的鸟类。样点法
Point transects可视距离低、异质性高、斑块状生境 较易发现,样地中分布均匀 对珍稀、罕见鸟种的调查效果较差 红外相机调查法
Camera trapping隐蔽布设红外相机 地面及林下层活动 主要适用于地栖性鸟类 ①调查物种间差异明显,能准确识别种类;
②照片拍摄率与鸟类的密度呈正相关;
③红外相机设置隐蔽,没有对鸟类行为活动造成影响。网捕法
Mist netting林地 森林内部鸟 难以调查林冠层活动的鸟类,鸟类有受伤和死亡的风险 标记重捕模型:
①种群封闭,种群数量在监测期内不变;
②个体间被捕获的概率相等;
③标记不影响个体的正常活动,且留存时间不能短于监测时间;
④第2次取样前个体充分均匀混合。网捕率表示相对多度:
①网捕率与鸟类的密度呈正相关;
②网捕过程没有影响鸟类的行为。鸣声调查法
Vocalization surveying噪音干扰较小 鸣声明显、独特 难以监测少鸣叫的种类和个体 鸣声计数:
①不同鸟类具有独特的鸣声,可区分其差异;
②能采集得到目标物种的高质量录音。声音指数反映多样性:
①鸟类鸣声具有特异性,随着物种数增加,鸣声特征将更加多样,表现为声音指数数值的变化。 -
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