Assessment On Effect Of River Restoration In North Rural Area

The neglective effects to rivers ecosystem`health is that most of natural rivers in thestate of channelization and non-continuity. With the development of society, economy andenvironmental awareness, more and more people realize the importance of river health; for byriver health assessment, it not only can describe and reflect rivers`health state in specialperiod, but also provide background information for river managers, and guide the work ofrive restoration.So, this paper take the river restoration project in Erdao District, Changchun City ascases study of river health assessment of rural area in North, with the following aspects:riparian zone land variety per year, herbaceous plant species and diversity, bank erosioncondition under flood, ecological revetment pile damage degree and treatment effect ofoverflow weir to rubbish inside the small watershed, then make a final habitat assessmentwith EPA`RBP. The main results are:1. The area of riparian zone land decrease year by year and most occupancy occurred in2011. Reduction of both sides of the north and the south is2451.9m3and1542.31m3respectively. The main reason is lack of river management and occupancy from farmland.2. There are25herbaceous plants belonging to18families,25genera. The wholecoverage and biodiversity increases year by year, with1.44in biodiversity index and90.25%in coverage. In2012, only the biodiversity in A4plot is recovered, this is because grazing,pesticide spraying and clipping affect normal development of plant, resulting in thatsagebrush colonized most of riverine.3. There is a total erosion amount of249.25±1.54m3along the riverbank with1000length. In September2012, the whole pile breakage rate is15.52%，and this shows that pilerevetment still need artificial maintenance and management such as we should displace thoseinclined pile before they generate more chain destruction along the riverbank.4. Overflow weirs in upstream and downstream with special design structure interceptmost rubbish such as plastic bags, plastic bottles and maize straw, but there is not obviousdifference in the following rubbish such as ampulla (fragile), discarded clothing and pesticidebottle(less common).5. Through rapid habitat assessment from2010to2012, the effect of river restoration increases, and human interrupt still has negative effect on part of river.