environment. But the obligation of watercourse States under artiale 25 is separate from, and additional to, the obligation0 set forth In articles 22 to 24. Thus, a watercourse State could conceivably demage an eetuary through pollution of an international watercourea [system] without breaching its obligation not to cause appreciable harm to other watercourse States. Article 25 would require the former wateraourae State to take the measures necebeary to protect and preserve the estuary. (3) The exprebleion “take all measures . , . neceBriaryl’ has the same meaning,v, as in article 24. m/ In the present aaBe, watercourse States are to take all of the necessary meaeures of which they are capable, financially and technologically. The expreseion “individually or jointly” ’ aleo hCiB the 8ame meaning,v, ae in articles 22 J.JJ/ and 25, paragraph 2. a/ Thus, where appropriate , watercourse States are to take joint, co-operative action to protect the marine environment from pollution carried there by an international watercouroe [system]. Such action is to be z.amSee article 194, para. 3 (a), and article 207. 2.w See e.g. the agreements cited in m, note 175. See also tha Ministerial Declaration6 of the various International Conferences on the Protection of the North Seal the First International Conference (Bremen, 31 October-l November 1984); the Second International Conference (London, 24-25 Novenber 1987)r and the Third International Conference (The Hague, 8 March 1990). 2.w See paragraph (3) of the commentary to article 24, zl.21 See paragraph (4) of the commentary to article 22. z.JN See paragraph (5) of the commentary to article 23. - 170 -taken on an equitable basis, which means that the obligation of watercourse States to participate in the measures in question is a function of their responaihility for the damage to the marine environa qt, or threat thereof.
**Analysis**
The text discusses the obligations of watercourse States under international law to protect and preserve the marine environment from pollution. The text specifically focuses on the measures that watercourse States must take to prevent harm to other watercourse States, as well as the role of joint, cooperative action in protecting the marine environment. The text does not appear to be related to economic development, agriculture, forestry, fishing, industry, transport, communication, international trade, health, education, employment, humanitarian aid, or culture. Instead, it seems to be primarily focused on the natural resources and environment category.

**Category**
Natural resources and environment