On the morning of October 28, Wu Lei, deputy director of the Weinan Municipal Assessment Office, Zhu Xiaohui, chief of the Evaluation Section of the Municipal Assessment Office, Jin Liqiang, a fourth-level researcher of the Municipal Bureau of Commerce, Yang Zhuojuan, a fourth-level director of the Municipal Bureau of Statistics, Tong Qiang, a cadre of the Investment Section of the Municipal Development and Reform Commission, yan Xiaojing, a second-level director of the Municipal Bureau of Industry and Information Technology, accompanied by Liu Baolin, secretary of the Linwei District Party Committee, Li Shusheng, deputy secretary of the District Party Committee and mayor of the district, Ma Zhanbin, deputy secretary of the District Party Committee, Wang Zhipeng, deputy secretary of the party group of the district party committee, and Wang Zhipeng, deputy secretary of the party group of the district government, Duan Shumei, member of the standing committee of the district party committee and director of the organization department, and other leaders. Came to investigate the comprehensive treatment project of the north slope of the south and north slopes.
The first phase of the ecological treatment and restoration project of the north slope of nanyuan in the central urban area is located on both sides of the newly built Jiefang South Road, covering an area of 1,200 mu. Adhering to the design concept of "three transformations, two increases, three measures and two formations", the project improves the ecological environment through the main measures of "cutting steep slopes, leaving gentle slopes, building dry streams, stopping floods, and combining qiao shrubs and vines with restoration of vegetation", with the principle of "protection first, natural restoration as the mainstay", implementing the spirit of General Secretary Xi Jinping's speech on protecting the ecological environment of the Yellow River Basin, creating an ecological barrier in the southern part of the main urban area, and forming a large-scale and fully functional country park in Weinan.
There were ecological problems in the early stages
First, the vegetation coverage is low, and afforestation is difficult.
The vegetation status of the ecological treatment and restoration project on the northern slope of the south ridge before the transformation of the landscape was farmland, economic forest land and wasteland, and the loess of the lower part of the economic forest was exposed, and the vegetation coverage of the wasteland was 45%. The Forestry Bureau has insisted on afforestation for many years, but because part of the land on the surface is arable land, afforestation is mostly selected for afforestation, the planting area is small, the slope is difficult to plant, and the vegetation coverage of the entire surface is low.
Second, the plant community is simple, and the quality of the forest stand is poor.
Before the transformation, the afforestation plant varieties were basically cypresses, with slow growth rate, weak reproductive and diffusion ability, simple plant community structure, single afforestation method, and poor forest stand quality.
Third, the surface cannot store water, and the soil erosion is serious.
The loess plateau south of the Weihe River is mainly formed by the development of the Weihe River and its tributaries. The entire loess plateau is high and low, tilting towards the river valley, the soil on the surface has limited water capacity and water infiltration, and the rainwater that cannot be infiltrated is discharged from the surface, and when the rainfall is large, even the soil is washed away, and the soil erosion is serious.
Overall engineering construction planning
First, the construction concept
Look at the city from a distance, look at the scenery from close, and take a nap under the forest;
Cut steep slopes, leave gentle slopes, build dry streams, stop floods, and protect water and soil from erosion.
Located on the south side of the main urban area, the north slope of Nanyuan is mainly formed by the development of the WeiHe River and its tributaries, and the land is basically irrigated by rainwater. This ecological restoration takes "Shanshui Lintian Lake is a community of life" as the guiding ideology, adheres to the "4432" greening model of Weinan City, adopts the sponge city concept in accordance with the layout of "one heart, two belts, three rivers and four layers" in Linwei District, Weinan City, comprehensively considers land consolidation, rainwater collection, plant community structure, landscape effect, village and regional culture, etc., vigorously promotes suburban protection, soil and water conservation, regional cultural restoration, carries out overall, systematic and comprehensive ecological governance, and creates a "forest city, garden city, Livable and tourist-friendly cities", build a crisscrossing ecological network, create a community of life in shanshui lintian lake, and create a livable and livable new Weinan.
Ecological dry creek general layout
Second, the principle of construction
Innovative ideas
Apply the sponge city concept in the Loess Plateau area, break the thesis that the sponge city is only for the southern water-rich city, and follow the eight-character policy of "interception, introduction, stagnation, retention, storage, net, use and discharge", fully and comprehensively utilize the rainwater on the surface and replenish groundwater, and innovate the theory of ecological restoration in the Loess Plateau area.
System repair
The design starts from the levels of rainwater interception and utilization, alternating planting of deep-rooted plants and shallow-rooted plants to fix soil, slope ecological protection, and increase and reduce soil erosion, and carry out systematic restoration of underwater water, soil and plant communities.
Coordinate the layout
According to the height difference of the terrain, the ponds are arranged in a coordinated manner, and they are connected in series according to the direction of the terrain, and on the basis of ecological restoration, landscape forests and observation decks are built to achieve ecological and social benefits.
Adapt to local conditions
On the basis of fully understanding the terrain, the existing low-lying land and ravines are used to store water, and the easy ditches are ditches, easy ponds and easy islands are used to create natural landscape forest areas.
Ecological measures
Vegetation solidification:
Trees + shrubs + ground cover: change the way rainwater falls, reduce the impact of rainwater and form runoff.
Vine slope protection: Huang Xin, eagle claw bean, six wood and other applications of ecological bags, fish scale pits, etc. for slope ecological protection, reduce runoff erosion, solid soil anti-landslide.
Leaves in the forest are not cleaned: reduce rain hitting the surface and reduce the formation of runoff washout.
Deep roots and shallow combination with plants: Plant roots are intertwined to hold the ground and deep soil to prevent soil erosion and landslides.
Sharp slopes, gentle slopes:
Because of its topography, slopes are prone to surface runoff, which in turn washes away the soil and causes soil erosion. The ecological restoration of the north slope of the south ridge sorts out the area with steep slope (greater than 25°), cuts off the steep and easy to collapse and landslides, and forms a gentle slope to reduce the soil erosion caused by surface runoff erosion. Gentle slope nature, combined with dry creek, high and low undulating, water gathering, water storage, water management, the rainwater beads left in it, the formation of blisters, rain gardens, etc., to replenish groundwater.
Comparison chart of ecological governance restoration
Before repair
After the repair
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After restoration (winter summer)
After restoration (Dry Creek)
With shining stars and beautiful rainbows, flowers and trees, a beautiful pattern of looking at the starry sky, seeing the green mountains, and smelling the fragrance of flowers is used, which embodies the historical picture of the new era, new ideas, new goals, and new journeys, and shows the current situation of people's beautiful life.
At present, the ecological treatment and restoration project of the north slope of nanyuan - country park has been roughly completed, and beautiful scenery such as flower sea, bamboo forest, and ginkgo avenue can be seen everywhere. The general public and friends can drive to watch the leisure weekend with three or five friends and feel a warm and beautiful summer.
Source: Yuan Zehui Culture