Linguistics is the scientific study of language, and involves an analysis of language form, language meaning, and language in context. The earliest activities in the documentation and description of language have been attributed to the 6th century BC Indian grammarian Pāṇini, who wrote a formal description of the Sanskrit language in his Aṣṭādhyāyī.
Like all ecosystems on Earth supporting animal and plant life, aquatic ecosystems need oxygen. However, oxygen availability in these systems is threatened by global warming and excessive input of nutrients such as from agriculture and wastewaters, known as eutrophication.
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