SM2+：自然環(huán)境超長時間錄音的分析與可視化

Abstract

Advances in technology and reduction in data storage costs enable the autonomous collection of large quantities of continuous audio recordings. While the collection of very long environmental recordings has become easier, the analysis of these recordings remains challenging. A very-long-duration audio recording is defined as one with a minimum length of one day, but may have durations of weeks, months, or years. This thesis provides methods for data reduction and visualisation that enable the ecological interpretation and navigation of very-long-duration audio recordings.

The major theme of data reduction commenced after the establishment of protocols and the collection of two thirteen-month continuous audio recordings from two separate Southeast Queensland forest ecosystems. The acoustic indices calculated on one-minute audio segments were used to develop two new techniques to visualise the contents of very long-duration recordings. An acoustic index is a mathematical expression used to measure a particular aspect of the energy distribution in audio recordings. Microphone failure in one channel was noticed shortly after the recording commenced. A method was established to detect microphone problems in long recordings.

A novel error measure was developed to detect seasonal and site differences and enable optimisation of the clustering based on seasonal and site differences in the data. Cluster interpretation on very-long-duration audio recordings is problematic because listening to large amounts of audio is time-consuming and therefore impractical. To overcome this, a series of five methods were developed to build on the interpretations made through listening. These methods enabled the allocation of an acoustic label to each cluster, resulting in a labelled acoustic sequence. This acoustic sequence was used to develop three additional visualisation techniques.

The culmination of the methods developed in this thesis was the six case studies. These extended the ecological interpretation of the acoustic sequence beyond those that were made through the visualisations. The case studies demonstrated that clustering can facilitate ecological interpretation of very-long-duration audio recordings.

摘要：

技術(shù)的進(jìn)步和數(shù)據(jù)存儲成本的降低使得能夠自主收集大量連續(xù)的音頻記錄。雖然收集非常長的環(huán)境記錄變得更加容易，但對這些記錄的分析仍然具有挑戰(zhàn)性。非常長持續(xù)時間的錄音被定義為最小長度為一天的錄音，但可能持續(xù)數(shù)周、數(shù)月或數(shù)年。本文提供了數(shù)據(jù)簡化和可視化的方法，使長時間音頻記錄的生態(tài)解釋和導(dǎo)航成為可能。

在制定協(xié)議并從昆士蘭州東南部兩個獨(dú)立的森林生態(tài)系統(tǒng)收集了兩份為期13個月的連續(xù)錄音后，數(shù)據(jù)減少的主要主題開始了。基于一分鐘音頻片段計算的聲學(xué)指數(shù)被用于開發(fā)兩種新技術(shù)，以可視化長時間錄音的內(nèi)容。聲學(xué)指數(shù)是一種數(shù)學(xué)表達(dá)式，用于測量錄音中能量分布的特定方面。錄音開始后不久，發(fā)現(xiàn)一個通道的麥克風(fēng)出現(xiàn)故障。建立了一種檢測長錄音中麥克風(fēng)問題的方法。

開發(fā)了一種新的誤差度量來檢測季節(jié)和地點(diǎn)差異，并能夠根據(jù)數(shù)據(jù)中的季節(jié)和地點(diǎn)的差異優(yōu)化聚類。對持續(xù)時間很長的錄音進(jìn)行集群解釋是有問題的，因為聽大量的音頻很耗時，因此不切實際。為了克服這一點(diǎn)，開發(fā)了一系列五種方法，以通過聽力進(jìn)行的解釋為基礎(chǔ)。這些方法能夠為每個簇分配一個聲學(xué)標(biāo)簽，從而產(chǎn)生一個標(biāo)記的聲學(xué)序列。該聲學(xué)序列用于開發(fā)三種額外的可視化技術(shù)。

本文開發(fā)的方法的高潮是六個案例研究。這些將聲學(xué)序列的生態(tài)學(xué)解釋擴(kuò)展到了通過可視化所做的解釋之外。案例研究表明，聚類可以促進(jìn)對長時間音頻記錄的生態(tài)解釋。

關(guān)鍵詞：聲學(xué)指標(biāo)、人類聲學(xué)、生物聲學(xué)、生物生物學(xué)、Diel圖；點(diǎn)陣圖、生態(tài)聲學(xué)、生態(tài)監(jiān)測、檢波器、長時間假彩色光譜圖、主成分分析、聲景生態(tài)學(xué)、超長時間錄音、可視化。