Effect of Ecological Construction Engineering on Vegetation Restoration: A Case Study of the Loess Plateau

Since the 1980s, with rapid economic development and increased attention given to ecological protection, China has launched a series of ecological-restoration programs to restore the local environment through afforestation and natural forest protection. The evaluation of vegetation restoration is an important part of evaluating the effectiveness of ecological restoration. The Loess Plateau is an area where ecological problems are concentrated, and it is a key area of ecological construction in China. This paper takes the Loess Plateau as the research area, using remote sensing and geographic information technology combined with ecosystem structural changes and an improved residual model to study vegetation restoration. The following main conclusions were drawn: (1) From 1990 to 2000, the farmland area increased by 3084.81 km2, resulting in the encroachment of a large area of grassland and shrubland. (2) With the implementation of ecological engineering, the area of returning farmland to forest and grassland reached 18,001.88 km2; in this period, the NDVI of vegetation increased rapidly, and the area that increased comprised 91.90% of the total area, of which the area of significant increase reached 65.78%. The quality of vegetation was restored to a great extent, and ecological engineering played a major role in this stage. (3) Under the background of large-scale implementation of ecological restoration, the urban area of the Loess Plateau continues to expand.

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Effects of Vegetation Restoration on Soil Erosion on the Loess Plateau: A Case Study in the Ansai Watershed

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18126266 ◽

2021 ◽

Vol 18 (12) ◽

pp. 6266

Author(s):

Hui Wei ◽

Wenwu Zhao ◽

Han Wang

Keyword(s):

Land Use ◽

Soil Erosion ◽

Loess Plateau ◽

Water Conservation ◽

Large Scale ◽

Land Use Changes ◽

Vegetation Restoration ◽

The Loess Plateau ◽

Local Soil ◽

Erosion Environment

Large-scale vegetation restoration greatly changed the soil erosion environment in the Loess Plateau since the implementation of the “Grain for Green Project” (GGP) in 1999. Evaluating the effects of vegetation restoration on soil erosion is significant to local soil and water conservation and vegetation construction. Taking the Ansai Watershed as the case area, this study calculated the soil erosion modulus from 2000 to 2015 under the initial and current scenarios of vegetation restoration, using the Chinese Soil Loess Equation (CSLE), based on rainfall and soil data, remote sensing images and socio-economic data. The effect of vegetation restoration on soil erosion was evaluated by comparing the average annual soil erosion modulus under two scenarios among 16 years. The results showed: (1) vegetation restoration significantly changed the local land use, characterized by the conversion of farmland to grassland, arboreal land, and shrub land. From 2000 to 2015, the area of arboreal land, shrub land, and grassland increased from 19.46 km2, 19.43 km2, and 719.49 km2 to 99.26 km2, 75.97 km2, and 1084.24 km2; while the farmland area decreased from 547.90 km2 to 34.35 km2; (2) the average annual soil erosion modulus from 2000 to 2015 under the initial and current scenarios of vegetation restoration was 114.44 t/(hm²·a) and 78.42 t/(hm²·a), respectively, with an average annual reduction of 4.81 × 106 t of soil erosion amount thanks to the vegetation restoration; (3) the dominant soil erosion intensity changed from “severe and light erosion” to “moderate and light erosion”, vegetation restoration greatly improved the soil erosion environment in the study area; (4) areas with increased erosion and decreased erosion were alternately distributed, accounting for 48% and 52% of the total land area, and mainly distributed in the northwest and southeast of the watershed, respectively. Irrational land use changes in local areas (such as the conversion of farmland and grassland into construction land, etc.) and the ineffective implementation of vegetation restoration are the main reasons leading to the existence of areas with increased erosion.

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Regional effects of vegetation restoration on water yield across the Loess Plateau, China

Hydrology and Earth System Sciences ◽

10.5194/hess-16-2617-2012 ◽

2012 ◽

Vol 16 (8) ◽

pp. 2617-2628 ◽

Cited By ~ 103

Author(s):

X. M. Feng ◽

G. Sun ◽

B. J. Fu ◽

C. H. Su ◽

Y. Liu ◽

...

Keyword(s):

Land Cover ◽

Land Cover Change ◽

Ecological Restoration ◽

Loess Plateau ◽

Climatic Variability ◽

Vegetation Restoration ◽

Water Yield ◽

The Loess Plateau ◽

Regional Effects ◽

Annual Water

Abstract. The general relationships between vegetation and water yield under different climatic regimes are well established at a small watershed scale in the past century. However, applications of these basic theories to evaluate the regional effects of land cover change on water resources remain challenging due to the complex interactions of vegetation and climatic variability and hydrologic processes at the large scale. The objective of this study was to explore ways to examine the spatial and temporal effects of a large ecological restoration project on water yield across the Loess Plateau region in northern China. We estimated annual water yield as the difference between precipitation input and modelled actual evapotranspiration (ET) output. We constructed a monthly ET model using published ET data derived from eddy flux measurements and watershed streamflow data. We validated the ET models at a watershed and regional levels. The model was then applied to examine regional water yield under land cover change and climatic variability during the implementation of the Grain-for-Green (GFG) project during 1999–2007. We found that water yield in 38% of the Loess Plateau area might have decreased (1–48 mm per year) as a result of land cover change alone. However, combined with climatic variability, 37% of the study area might have seen a decrease in water yield with a range of 1–54 mm per year, and 35% of the study area might have seen an increase with a range of 1–10 mm per year. Across the study region, climate variability masked or strengthened the water yield response to vegetation restoration. The absolute annual water yield change due to vegetation restoration varied with precipitation regimes with the highest in wet years, but the relative water yield changes were most pronounced in dry years. We concluded that the effects of land cover change associated with ecological restoration varied greatly over time and space and were strongly influenced by climatic variability in the arid region. The current regional vegetation restoration projects have variable effects on local water resources across the region. Land management planning must consider the influences of spatial climate variability and long-term climate change on water yield to be more effective for achieving environmental sustainability.

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Relationship between multi-scale climate factors and performance of ecological engineering on the Loess Plateau, China

Journal of Forestry Research ◽

10.1007/s11676-021-01343-7 ◽

2021 ◽

Author(s):

Panxing He ◽

Jun Ma ◽

Zhiming Han ◽

Mingjie Shi ◽

Dongxiang Xu ◽

...

Keyword(s):

Atmospheric Circulation ◽

Loess Plateau ◽

Climatic Factors ◽

Gross Primary Production ◽

Ecological Engineering ◽

Climatic Conditions ◽

Vegetation Restoration ◽

The Loess Plateau ◽

Engineering Project ◽

Multi Scale

AbstractThe long-term “Grain-to-Green Program” (GGP) on China’s Loess Plateau is a major global ecological engineering project which has significantly boosted vegetation renewal. Some studies have found that the rate of restoration is quite rapid during the implementation of ecological engineering, however, the influence of multi-scale climatic conditions on the performance of ecological engineering is unclear. In this study, multiple sources of remote sensing data were used to estimate the dynamics of vegetation structural and functional indicators, water-related local climatic factors, and atmospheric circulation factors. These datasets were also used to detect possible causes for vegetation restoration on the Loess Plateau over the past 20 years. The results show that widespread increases in rates of normalized difference vegetation indexes (NDVI), leaf area indexes (LAI), gross primary production (GPP), and aboveground biomass carbon (ABC) during 2000–2016 were significantly higher than before 2000. GPP was significantly correlated with rainfall and surface runoff on a monthly scale, and there were significant positive correlations between GPP and atmospheric circulation. Our results demonstrate that both vegetation structural and functional indicators rapidly increase, and ecological engineering greatly accelerated vegetation restoration after 2000. Local climatic conditions and atmospheric circulation patterns enhance vegetation growth and impact of ecological engineering.

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Regional effects of vegetation restoration on water yield across the Loess Plateau, China

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-9-4161-2012 ◽

2012 ◽

Vol 9 (3) ◽

pp. 4161-4191 ◽

Cited By ~ 7

Author(s):

X. M. Feng ◽

G. Sun ◽

B. J. Fu ◽

C. H. Su ◽

Y. Liu ◽

...

Keyword(s):

Land Cover ◽

Land Cover Change ◽

Ecological Restoration ◽

Loess Plateau ◽

Climatic Variability ◽

Vegetation Restoration ◽

Water Yield ◽

The Loess Plateau ◽

Regional Effects ◽

Annual Water

Abstract. The general relationships between vegetation and water yield under different climatic regimes are well established at a small watershed scale in the past century. However, applying the basic theories to evaluate the regional effects of land cover change on water resources has been rarely done due to the complex interactions of vegetation and climatic variability and hydrologic processes at the large scale. The objective of this study was to explore ways to examine the spatial and temporal effects of a large ecological restoration project on water yield across the Loess Plateau region in Northern China. We estimated annual water yield as the difference between precipitation input and modeled actual evapotranspiration (ET) output. We constructed a monthly ET model using published eddy flux ET measurements, ET estimates derived from local watershed streamflow data. We validated the ET models at a watershed and regional levels. The model was then applied to examine regional water yield under land cover change and climatic variability during the implementation of the Grain-for-Green (GFG) project during 1999–2007. We found that water yield in 38% of the Loess Plateau area as a whole might have decreased (1–48 mm yr−1) as a result of land cover change alone. However, combined with climatic variability, 37% of the study area might have seen a decrease in water yield with a range of 1–54 mm yr−1, and 35% of the study area might have seen an increase with a range of 1–10 mm yr−1. Across the study region, climate variability masked or strengthened the water yield response to vegetation restoration. The absolute annual water yield change due to vegetation restoration varied with precipitation regimes with the highest in wet years, but the relative water yield changes were most pronounced in dry years. When compared to findings at the plot or catchment-scale, this study suggested that regional hydrologic effects of vegetation restoration practices had a rather complex pattern due to both spatial differences in climatic regimes and vegetation response. We concluded that the effects of land cover change associated with ecological restoration varied greatly over time and space and were strongly influenced by climatic variability in the arid region. The current regional vegetation restoration projects have variable effects on local water resources across the region. Land management planning must consider the influences of spatial climate variability and long-term climate change on water yield to be more effective and achieve environmental sustainability.

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Impact of large-scale vegetation restoration project on summer land surface temperature on the Loess Plateau, China

Journal of Arid Land ◽

10.1007/s40333-018-0105-z ◽

2018 ◽

Vol 10 (6) ◽

pp. 892-904 ◽

Cited By ~ 6

Author(s):

Guohua He ◽

Yong Zhao ◽

Jianhua Wang ◽

Qingming Wang ◽

Yongnan Zhu

Keyword(s):

Surface Temperature ◽

Loess Plateau ◽

Land Surface Temperature ◽

Land Surface ◽

Large Scale ◽

Vegetation Restoration ◽

The Loess Plateau ◽

Restoration Project

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Does Vegetation Restoration Change Regional Ecohydrological Condition at the Loess Plateau in China?

Environment and Natural Resources Research ◽

10.5539/enrr.v6n4p116 ◽

2016 ◽

Vol 6 (4) ◽

pp. 116

Author(s):

Xiongwen Chen ◽

Jianzhi Niu

Keyword(s):

Loess Plateau ◽

Large Scale ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Rainfall Intensity ◽

Vegetation Restoration ◽

Soil Water Storage ◽

The Loess Plateau ◽

Derived Data

The Loess Plateau is a severely eroded and very venerable area in the northwestern China. Large scale vegetation restoration has been conducted in this region during the recent decades, its effect on the regional ecohydrology is under concern. In this study, long term satellite and derived data were used to analyze regional hydrological condition at the major part of the Loess Plateau (35°-37°N and 105°-110° E). The results indicate that there was an increase in the regional normalized difference vegetation index, evapotranspiration, rainfall intensity, soil water storage (surface 1m layer) and runoff. It was also observed that the total annual precipitation did not change significantly.The possible mechanisms may be related to the complicated processes of vegetation on ecohydrology. Our results and approach may be useful to evaluate the benefits of ecological restoration and further vegetation restoration at the Loess Plateau and other regions.

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A Policy-Driven Large Scale Ecological Restoration: Quantifying Ecosystem Services Changes in the Loess Plateau of China

PLoS ONE ◽

10.1371/journal.pone.0031782 ◽

2012 ◽

Vol 7 (2) ◽

pp. e31782 ◽

Cited By ~ 231

Author(s):

Yihe Lü ◽

Bojie Fu ◽

Xiaoming Feng ◽

Yuan Zeng ◽

Yu Liu ◽

...

Keyword(s):

Ecosystem Services ◽

Ecological Restoration ◽

Loess Plateau ◽

Large Scale ◽

The Loess Plateau

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Contributions of Vegetation Greening and Climate Change to Evapotranspiration Trend after Large-Scale Vegetation Restoration on the Loess Plateau, China

Water ◽

10.3390/w13131755 ◽

2021 ◽

Vol 13 (13) ◽

pp. 1755

Author(s):

Shuo Wang ◽

Chenfeng Cui ◽

Qin Dai

Keyword(s):

Climate Change ◽

Loess Plateau ◽

Large Scale ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Potential Evapotranspiration ◽

Development Trend ◽

Future Trend ◽

Natural Ecosystem ◽

The Loess Plateau

Since the early 2000s, the vegetation cover of the Loess Plateau (LP) has increased significantly, which has been fully recorded. However, the effects on relevant eco-hydrological processes are still unclear. Here, we made an investigation on the changes of actual evapotranspiration (ETa) during 2000–2018 and connected them with vegetation greening and climate change in the LP, based on the remote sensing data with correlation and attribution analysis. Results identified that the average annual ETa on the LP exhibited an obvious increasing trend with the value of 9.11 mm yr−1, and the annual ETa trend was dominated by the changes of ETa in the third quarter (July, August, and September). The future trend of ETa was predicted by the Hurst exponent. Partial correlation analysis indicated that annual ETa variations in 87.8% regions of the LP were controlled by vegetation greening. Multiple regression analysis suggested that the relative contributions of potential evapotranspiration (ETp), precipitation, and normalized difference vegetation index (NDVI), to the trend of ETa were 5.7%, −26.3%, and 61.4%, separately. Vegetation greening has a close relationship with the Grain for Green (GFG) project and acts as an essential driver for the long-term development trend of water consumption on the LP. In this research, the potential conflicts of water demanding between the natural ecosystem and social-economic system in the LP were highlighted, which were caused by the fast vegetation expansion.

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Quantifying the Responses of Evapotranspiration and Its Components to Vegetation Restoration and Climate Change on the Loess Plateau of China

Remote Sensing ◽

10.3390/rs13122358 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2358

Author(s):

Linjing Qiu ◽

Yiping Wu ◽

Zhaoyang Shi ◽

Yuting Chen ◽

Fubo Zhao

Keyword(s):

Climate Change ◽

Loess Plateau ◽

Dominant Role ◽

Vegetation Restoration ◽

Vegetation Coverage ◽

Ecological Planning ◽

The Loess Plateau ◽

Canopy Interception ◽

Community Land Model ◽

Spatiotemporal Trends

Quantitatively identifying the influences of vegetation restoration (VR) on water resources is crucial to ecological planning. Although vegetation coverage has improved on the Loess Plateau (LP) of China since the implementation of VR policy, the way vegetation dynamics influences regional evapotranspiration (ET) remains controversial. In this study, we first investigate long-term spatiotemporal trends of total ET (TET) components, including ground evaporation (GE) and canopy ET (CET, sum of canopy interception and canopy transpiration) based on the GLEAM-ET dataset. The ET changes are attributed to VR on the LP from 2000 to 2015 and these results are quantitatively evaluated here using the Community Land Model (CLM). Finally, the relative contributions of VR and climate change to ET are identified by combining climate scenarios and VR scenarios. The results show that the positive effect of VR on CET is offset by the negative effect of VR on GE, which results in a weak variation in TET at an annual scale and an increased TET is only shown in summer. Regardless of the representative concentration pathway (RCP4.5 or RCP8.5), differences resulted from the responses of TET to different vegetation conditions ranging from −3.7 to −1.2 mm, while climate change from RCP4.5 to RCP8.5 caused an increase in TET ranging from 0.1 to 65.3 mm. These findings imply that climate change might play a dominant role in ET variability on the LP, and this work emphasizes the importance of comprehensively considering the interactions among climate factors to assess the relative contributions of VR and climate change to ET.

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