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Assessing Vegetation Cover Dynamics Induced by Policy-Driven Ecological Restoration and Implication to Soil Erosion in Southern China.

Zhang J, Wang T, Ge J - PLoS ONE (2015)

Bottom Line: In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide.The conversions of croplands on steep slopes to forests resulting from national policies led to significant increases in EVI.Increase in the area of farmland-converted forestlands has reduced soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology & College of Life Sciences, Beijing Normal University, Beijing, PR China; Earth and Environmental Sciences Department, Lehigh University, Bethlehem, Pennsylvania, United States of America.

ABSTRACT
In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide. However, it is still unclear how vegetation has changed in southern China since the launch of these programs. In this study, we used the MODIS Enhanced Vegetation Index (EVI) to analyze the vegetation cover dynamics in southern China from 2000 to 2009 and evaluate the resulting effects of controlling soil erosion. Our observations indicate that 5.3% of the study area significantly increased and 0.98% significantly decreased in EVI value (p < 0.05). The spring EVI had largest increase in space. The conversions of croplands on steep slopes to forests resulting from national policies led to significant increases in EVI. The increase in EVI was not driven by annual average temperature and annual precipitation. By referencing ecological restoration statistical data and field observations, we showed that ecological restoration programs significantly improved vegetation cover in southern China. Increase in the area of farmland-converted forestlands has reduced soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River. This study displays the spatial patterns of trend in vegetation growth since the beginning of the 21st century in southern China and highlights the important role of China's afforestation program.

No MeSH data available.


Related in: MedlinePlus

The land use for the area with significantly increased EVI on slopes of 0–15° in 2000 (a) and 2009 (b) and on slopes >15° in 2000 (c) and 2009 (d).
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pone.0131352.g008: The land use for the area with significantly increased EVI on slopes of 0–15° in 2000 (a) and 2009 (b) and on slopes >15° in 2000 (c) and 2009 (d).

Mentions: According to the two slope categories, the LULC types of the area with significantly increased EVI for both 2000 and 2009 are shown in Fig 8 and S3 Fig. Agricultural land was the dominant type on slopes of 0–15° in 2000. On slopes of 0–15° cropland decreased by 6.5×104 km2 and forest, shrubland, and grassland increased by 2.5×104 km2, 1.6×104 km2, and 1.0×104 km2, respectively, from 2000 to 2009 (S3 Fig). The region with the most apparent change is north of Chongqing and the transitional zone of Sichuan, Yunnan and Guizhou, where cropland was significant in 2000 but decreased in 2009. On slopes above 15°, cropland decreased by 3.0×104 km2, and forest, shrubland, and grassland increased by 1.0×104 km2, 1.0×104 km2, and 0.5×104 km2, respectively. However, in the northern part of Chongqing and the transitional zone of Sichuan, Yunnan and Guizhou, the forest increased and cropland decreased significantly. The local forestry administrations provided the information of land cover of selected sites where we conducted field investigation and took 520 field photos. The data indicated that the vegetation recovered significantly after the restoration policies were carried out in these regions (S1 Fig).


Assessing Vegetation Cover Dynamics Induced by Policy-Driven Ecological Restoration and Implication to Soil Erosion in Southern China.

Zhang J, Wang T, Ge J - PLoS ONE (2015)

The land use for the area with significantly increased EVI on slopes of 0–15° in 2000 (a) and 2009 (b) and on slopes >15° in 2000 (c) and 2009 (d).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4482633&req=5

pone.0131352.g008: The land use for the area with significantly increased EVI on slopes of 0–15° in 2000 (a) and 2009 (b) and on slopes >15° in 2000 (c) and 2009 (d).
Mentions: According to the two slope categories, the LULC types of the area with significantly increased EVI for both 2000 and 2009 are shown in Fig 8 and S3 Fig. Agricultural land was the dominant type on slopes of 0–15° in 2000. On slopes of 0–15° cropland decreased by 6.5×104 km2 and forest, shrubland, and grassland increased by 2.5×104 km2, 1.6×104 km2, and 1.0×104 km2, respectively, from 2000 to 2009 (S3 Fig). The region with the most apparent change is north of Chongqing and the transitional zone of Sichuan, Yunnan and Guizhou, where cropland was significant in 2000 but decreased in 2009. On slopes above 15°, cropland decreased by 3.0×104 km2, and forest, shrubland, and grassland increased by 1.0×104 km2, 1.0×104 km2, and 0.5×104 km2, respectively. However, in the northern part of Chongqing and the transitional zone of Sichuan, Yunnan and Guizhou, the forest increased and cropland decreased significantly. The local forestry administrations provided the information of land cover of selected sites where we conducted field investigation and took 520 field photos. The data indicated that the vegetation recovered significantly after the restoration policies were carried out in these regions (S1 Fig).

Bottom Line: In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide.The conversions of croplands on steep slopes to forests resulting from national policies led to significant increases in EVI.Increase in the area of farmland-converted forestlands has reduced soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River.

View Article: PubMed Central - PubMed

Affiliation: State Key Laboratory of Earth Surface Processes and Resource Ecology & College of Life Sciences, Beijing Normal University, Beijing, PR China; Earth and Environmental Sciences Department, Lehigh University, Bethlehem, Pennsylvania, United States of America.

ABSTRACT
In the aftermath of the severe droughts and floods at the end of the 20th century, the Chinese government launched several ecological restoration projects, including the Natural Forest Protection Program in 1998 and the Grain-for-Green Program in 1999, to promote afforestation and reforestation to reduce surface runoff and consequent soil erosion nationwide. However, it is still unclear how vegetation has changed in southern China since the launch of these programs. In this study, we used the MODIS Enhanced Vegetation Index (EVI) to analyze the vegetation cover dynamics in southern China from 2000 to 2009 and evaluate the resulting effects of controlling soil erosion. Our observations indicate that 5.3% of the study area significantly increased and 0.98% significantly decreased in EVI value (p < 0.05). The spring EVI had largest increase in space. The conversions of croplands on steep slopes to forests resulting from national policies led to significant increases in EVI. The increase in EVI was not driven by annual average temperature and annual precipitation. By referencing ecological restoration statistical data and field observations, we showed that ecological restoration programs significantly improved vegetation cover in southern China. Increase in the area of farmland-converted forestlands has reduced soil erosion based upon monitoring sediment yields at hydrologic stations in the Yangtze River. This study displays the spatial patterns of trend in vegetation growth since the beginning of the 21st century in southern China and highlights the important role of China's afforestation program.

No MeSH data available.


Related in: MedlinePlus