| 其他摘要 | The traditional guiding ideology and treatment on soil erosion control pay attention to
ecological and economic benefits of the harnessing area，which will reduce the sediment
yield. However, the reduction of sediment could lead to the decrease of water, which will
aggravate the water contradiction between upstream and downstream in the water source
areas of Beijing and Tianjin. Environmental effects of traditional slope and channel
measures on water and sediment were studied by investigation and ecological
water-carrying treatment was studied by location experiment in Dongbei watershed
locating in Pingquan County, Chengde City. The problems about building ecological
water-carrying watershed should be improve from slope of forest and grass measures, slope
engineering measures and channel engineering measures. The main results were
summarized as follows:
(1) The traditional slope of forest and grass measures pay attention to economic benefits，
building lots of commercial forest, economic forest and firewood forest which increase
water consumption of living being and reduce runoff. Especially when the grass cover
degree is effective, bringing slope engineering measures into force may reduce runoff and
induce soil erosion. Results showed that natural meadow has best runoff-increase and
soil-reduce. For moderate and mild degraded grassland under the management of closing
hills , the vegetation coverage could improve by 2.84% and 1.97% in shady slope and
sunny slope per year. Large areas of moderate and mild degraded grassland under the
management of closing hills could not only reduce sediment yield ，recover vegetation,but
also increase runoff, if give up economic benefits of the harnessing area under the
backround of eco-compensate and eco-security.
(2) The traditional slope engineering measures were design by average runoff of many
years, traditional fish-scale pits measures had significant effects on sediment trapping and
reduction of water yield. Building eco-water transfer watershed, some traditional measures like fish-scale pits should be limited in areas where occurred serious soil erosion，and their
preparation standard should be degraded. It suggests that the size of fish-scale pits could be
designed by sediment and the rate of grass recovering. Small fish-scale pits may be destroy
by downpour, suggesting that the outside of fish-scale pits can be reinforced by bamboo
which could not only reduce sediment, but also increase runoff. Some Hippophae
rhamnoides and native shrub grass should be plant in the small fish-scale pits, but not the
tree species of water consumption.
(3) The traditional channel engineering measures have problems of less sedimentation.
Masonry check dam usually form small reservoir causing large of runoff evaporation. Dry
masonry check dam often destroy under overproof rainstorm. The traditional channel
engineering measures have two defects, one the one hand, low-use water resource, on the
other hand, increase manage cost. Building eco-water transfer watershed, the dam should
be developed on rational location and improve construction quality, designing according to
the condition of manages and erosion. A small watershed can have several types of dam,
adjusting measures to conditions and combine in-sand quantity and water transfer. Building
wood for fence check dam, dry masonry check dam, masonry check dam successively
from gully head to gully toe, which ensure reducing sediment and increasing water yield.
KeyWords：Eco-water transfer watershed；traditional watershed；soil erosion control；
relation between runoff and sediment；water source areas of Beijing and Tianjin |
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