51.   There, regardless of their contribution to the global climate, trees would bring local benefits, such as helping to prevent soil erosion.

52.   Their engineering is an important part of the ecology as they create wetlands and stop soil erosion in the runoff they prevent.

53.   They documented soil erosion and surface flooding, noted seasonal changes in ocean currents that influence climate, and measured the water content of mountain snow packs.

54.   They produce the oxygen we breathe, reduce air pollution, reduce air-conditioning costs and discourage soil erosion.

55.   This type of farming reduces plowing to prevent soil erosion and requires more herbicide to kill weeds.

56.   Those included the negative impact on industries such as tourism and salmon farming, as well as the cost of soil erosion and pollution.

57.   Under new rules, only land that meets criteria -- such as vulnerability to soil erosion -- can be enrolled in the program.

58.   Visitors are causing soil erosion, killing plantlife and silting up the streams.

59.   With soil erosion expected to increase dramatically, forest workers are cutting tree trunks and laying bales of hay in an effort to protect the city from mudslides.

60.   With the imagery, scientists are demonstrating they can assess crop density, forestation, soil erosion, rainfall and even the moisture content of mountainous snow packs.