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WETLAND AND WATER RESOURCE MODELING AND ASSESSMENT: A Watershed Perspective - Chapter 7

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Hồ sơ kiểm kê rừng chỉ ra rằng khu vực rừng ở Trung Quốc đã giảm từ 102 triệu ha năm 1949 khoảng 95 triệu ha vào năm 1980 do tăng trưởng dân số nhanh công nghiệp hóa, và quản lý yếu kém nguồn tài nguyên trong giai đoạn (Fang et al 2001, Liu và Diamond năm 2005.) . Do đó, khoảng 38% khối lượng đất của Trung Quốc được coi là bị xói mòn (Zhang et al 2000.) Do phá rừng và đô thị hóa nhanh chóng (Liu et al. 2005). Tuy nhiên, che phủ rừng đang phục hồi. | 7 Forest and Water Relations Hydrologic Implications of Forestation Campaigns in China Ge Sun Guoyi Zhou Zhiqiang Zhang Xiaohua Wei Steven G. McNulty and James Vose 7.1 INTRODUCTION Forest inventory records indicate that the forested area in China fell from 102 million hectares in 1949 to approximately 95 million hectares in 1980 due to accelerated population growth industrialization and resource mismanagement during that period Fang et al. 2001 Liu and Diamond 2005 . Consequently about 38 of China s land mass is considered badly eroded Zhang et al. 2000 due to deforestation and rapid urbanization Liu et al. 2005 . However forest coverage is recovering Liu and Diamond 2005 and China now has the largest area of forest plantations in the world accounting for approximately 45 million ha which is one fourth of the world total Food and Agriculture Organization FAO 2004 http www.fao.org Figure 7.1 . A new forest policy called the Natural Forest Conservation Program NFCP was adopted after the severe floods of 1998 Zhang et al. 2000 . This policy s objectives include restoring natural forests in ecologically sensitive areas such as the headwaters of several large rivers including the Yangtze River and the Yellow River planting trees for soil and water protection increasing timber production through forest plantations banning excessive cutting and maintaining the multiple use of forests. China s massive forestation plan Program for Conversion of Cropland to Forests aims to increase forested areas by 440 000 km2 or 5 of its landmass in the next 10 years Lei 2002 . This includes 14.66 million ha of soil erosion-prone croplands that will be converted to forests and 17.33 million ha of barren land that will be revegetated during the next ten years. Plot-scale studies in China have documented that reforestation and forestation can reduce soil erosion and sediment transport Zhou and Wei 2002 and enhance carbon sequestration Fang et al. 2001 . However surprisingly few rigorous .