Designing a winter bird atlas field methodology: issues of time and space in sampling and interactions with habitat
Designing a winter bird atlas field methodology: issues of time and space in sampling and interactions with habitat
复制标题
设计冬季鸟类地图集野外方法：采样的时间和空间问题以及与栖息地的相互作用
作者：
S. Gillings
区系和区系地图集可以提供有关物种分布和相对丰度的宝贵信息，并在检测和诊断种群变化方面发挥了关键作用。大多数地图集依赖于简单但有效的实地方法，可以被大量的志愿测量员采用，以便最好地利用他们有限的努力。对于鸟类学地图集，这种方法已被修改，以更好地量化繁殖季节的相对丰度。在这里，我们评估如何努力应该投资在空间（样本数量）和时间（每个样本的时间），以优化物种列表和相对丰度估计鸟类在英国和爱尔兰在冬季。物种积累曲线显示，无论是在时间上还是在空间上投入精力，得出完整物种清单的能力都只有轻微的差异。然而，如果以时间为代价在空间上投入精力，相对丰度的精确度会显著提高。这些结果给出了明确的指导方法的一般方式，应设计（即更多的样本，每一个更少的时间），但有关物种积累曲线的形状栖息地多样性的分析表明，精确的权衡测量在空间和时间之间的景观变化。因此，地图集的设计者必须针对特定地区的景观优化他们的研究设计。
Faunal and floral atlases can provide invaluable information on species distributions and relative abundance, and have played a key role in detecting and diagnosing population changes. Most atlases rely on simple but effective field methods that can be employed by large numbers of volunteer surveyors so as to make the best use of their finite effort. For ornithological atlases, such methods have been modified to better quantify relative abundance in the breeding season. Here, we evaluate how effort should be invested in space (number of samples) and time (time per sample) in order to optimise species lists and relative abundance estimation for birds in Britain and Ireland in winter. Species accumulation curves show only slight differences in the ability to derive complete species lists whether effort is invested in time or in space. However, relative abundance precision is markedly improved if effort is invested in space at the expense of time. These results give clear guidance on the general way in which methods should be devised (i.e. more samples, each for less time), but analyses relating the shape of species accumulation curves to habitat diversity suggest the precise trade-off between surveying in space and time varies between landscapes. Designers of atlases must therefore optimise their study design for the landscape of the particular region in question.