For M. phoebe, to decrease grazing, especially its effects on the source population during the post-hibernating larval group stage, is crucial for its population restoration and growth.

在春季减少源斑块内的放牧，对于以源-汇集合种群形式存在的大网蛱蝶种群恢复和增长十分必要；

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Population growth in Africa has long been a source of concern, as food and fresh water supplies are strained, but Kent argues that Africa's plentiful young may actually be viewed as its strength.

长久以来，随着紧张的食物和淡水供应，非洲的人口增长就是关注的源泉，但肯特坚决主张：实际上许多年轻人可以看做非洲的优点。

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Agriculture provided a more dependable source of food, causing populations to increase; eventually excess population migrated to new lands.

农业提供了更加可依赖的粮食来源，使人口增长；最终过多的人口迁移到新的土地。

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"It is crucial that national authorities do not rush to give information on source of infection which is not proven by bacteriological analysis, as this spreads unjustified fears in the population all over Europe, and creates problems for our food producers selling products in the EU and outside of the EU."

VOA: special.2011.06.10

Community media are a major source of news for most of the population and contribute to the well-being and development of ordinary citizens.

UNESCO: MEDIA SERVICES

Not only do games help Facebook keep a large segment of its population coming back, they are also an increasingly important source of revenue.

FORBES: Launching Platform-Wide Changes, Facebook Seeks to Up Its Social Game

"It signals to us that the source (of the caffeine) really isn't the high population centers, possibly because they are on wastewater treatment plants, " Granek told CNN.

CNN: Researchers find caffeine in waters off Oregon