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Emerging Challenges - New Findings

The nitrogen cascade: impacts of food and energy production on the global nitrogen cycle
Overfishing: harvesting fish faster than they can reproduce
Challenges for the future

New scientific research findings in 2003 on the nitrogen cycle and marine overfishing have shed light on ongoing environmental challenges of global significance. Both issues are emerging environmental challenges in terms of strategic and adaptive policy responses and action at appropriate levels

Human activity is radically altering the world’s nitrogen cycle through food and energy production. While some important foodproducing systems are nitrogen-deficient, others are generating excess nitrogen, affecting air, land, and freshwater, and ultimately environmental and human health. Nitrogen overload is also contributing to the rapid growth of oxygen-starved zones in some coastal waters. A new understanding of nitrogen cycling provides the opportunity to develop innovative and effective strategies to reduce the negative impacts of nitrogen on the environment and human health, while maintaining its benefits for society.

Three-quarters of the world’s fish stocks are being overexploited, threatening their existence, and jeopardizing the resources available for future generations. New data about fish stocks and the impacts of fishing methods provide a sound scientific foundation to develop effective management regimes.

Box 1: Defining emerging environmental

"An issue (positive or negative) which is not yet generally recognized but which may have significant impact on human and/or ecosystem health.

"Emerging issues are often not ‘new’ issues, but the intensification, wider extension, transformation or changed perception of familiar issues."

Source: Munn and others 2000

While both these emerging environmental issues (Box 1) are globally relevant, their extent, magnitude and impacts vary significantly at regional and lower levels. For example, problems related to nitrogen exist all over the world but the nature of the problem varies: there is too much nitrogen in some areas, while others have too little to meet human needs. Local and regional perspectives are, therefore, critically important to advance our understanding of the threats and opportunities they provide. This local and regional texture is also important in designing and implementing solutions because social, cultural, political, and economic factors need to be considered for sound and effective environmental management. It is also clear that, while people contribute to the problem, they are also part of the solution and human health risks.


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