The Study Of The Wetland Restoration Engineering Effect In Yellow River Delta

The study area of this paper is located in the Yellow River Delta Nature Reserve, Itsgeographical coordinates is1190506E~1190923.9E and374531.9N~374849.2N.The Yellow River Delta Nature Reserve has the most broad estuary wetland of warmtemperate zone in our country, and it is a important place for protecting species or for birdshabitat, it is one of the precious species gene pool in the world. Due to the developmentand utilization of land resources, the exploitation of petroleum and natural environmentevolution, the soil stalinization serious, the Yellow River delta wetland nature reserve issuffering a serious ecological degradation and a slowly evolution of new wetland. Thispaper attempts to reveal human interventional influence on the evolution of wetland, basedon the research of the wetland ecological restoration engineering effect, provide examplefor large-scale popularization of artificial ecological restoration in the future.According to different engineering measures of ecological restoration, this paper dividedexperimental area was into four areas:The compared area with completely naturalrestoration, the planted forest interference test area, the test area of north shore of theYellow River with levee-revetment restoration and the southern bank wetland plantcommunity recovery area of the Yellow River. Based on the research of the ecologicalcharacteristics in the region, combined with the existing theory achievement of many otherscholars, to find the main cause of ecological degradation in this region, and use reasonableappropriate human disturbance actively guidance, to provide excellent successionenvironment for ecological system, in order to promote the wetland ecosystem successionto a stable direction of structure and function. This study have important theoretical andpractical significance to maintaining the stability of resistance and resilience of theecosystem, improving the ecological environment of nature reserve, developing and usingof the resources of the Yellow River delta wetland, and the protection of system.Based on the instruction of the restoration ecology theory, through the on-the-spotinvestigation, the ecological statistical calculation, the determination of salinity and pH ofsoil, the vegetation analysis of TWINSPAN classification and DCA sorting, this paperstudied the effect of the wetland vegetation restoration engineering in Yellow River delta.This article’s main contents include the classification and sorting of the vegetation, thecomparison of the soil salinity and vegetation species diversity between the manual interventional region and no interventional region, the influence to plant communitystructure of different degree of artificial interference, the comparison of the vegetationfeatures between the above and below of the dam, and the investigation of the rule ofvegetation succession. The main research conclusions are as follows:1. Selected three to four sampling location in the four research areas, sampled two layerssoil samples at0~20cm and20cm-40cm depth, and determined the soil salinity and pHvalue in laboratory. The results showed: This results showed that the degree of soilsalinization is very serious, after two years recovery, in2012the degree of salinization ofsoil has improved slightly than in2010in the human interventional region, and in nohuman interventional area,the soil salinization degree hadn’t changed nearly in two years.2. Using PCORDWIN software for TWINSPAN classification of vegetation divided the13sample into three types: Communities of Suaeda glauca-Tamarix chinensis-Phragmites, Communities of Suaeda glauca–Phragmites and Communities of Suaedaglauca; Using DCA sorting divided the sample area into four types. The leadingenvironmental dominant factors that influence the four ecological types was the saltcontent of soil. The classification results of the two methods are nearly identical, it showedthat using TWINSPAN and DCA sorting for the vegetation quantity ranking andclassification research is feasible, and the results can be verified with each other.3. Compare the soil salinity and vegetation diversity between the human interventionalregion and no artificial interventional area, the results being as follows: Therefore in0~20cm depth and20cm~40cm range, the soil salinity and pH in manual interventional areawere less than not artificial interventional region. And in manual interventional region, thevegetation diversity index was higher than no human interventional area, the more theintense of human intervention, the soil salinity and pH value are lower, the diversity ofvegetation index is higher.4. Compare the soil salinity and vegetation diversity between the above of the artificialembankment and the below in the north shore of the Yellow River, the results being asfollows: The soil salinity and pH value at the top of dam were lower than the below of thedam; The soil salinity and pH value at layer of0-20cm were generally less than layer of20cm-40cm. Dam top consists of8species, and most of them were wet plants, the Damdown contains7species, and priorities were halophytes. The dam top has high biodiversity,ecosystem maturity was significantly higher than that of the dyke. Therefore, man-madedams was in favour of wetland ecological restoration in the recovery area of the YellowRiver delta. 5. Using ecological statistical method calculated the species important value, thediversity index, niche breadth and other ecological parameter of the typical samples, builtthe ecological system stability model and succession model, obtained the succession ruleof vegetation: Ordered according to the distance from the sea from near to far: Suaedaglauca community, Suaeda glauca-Tamarix chinensis community, Suaeda glauca-Tamarix chinensis-Phragmites communities alternate community, Corresponding to theabove result, the stability of ecological system was gradually from fragile to stable,succession levels ranged from junior to senior.Through the comparison and analysis of the wetland vegetation characteristics between thehuman interventional region and no artificial interventional area, it can be seen that,human intervention project has positive effects to the positive succession of plantcommunity, biodiversity increasing, the optimization of ecosystem structure and function,stable and continues of the resource providing ability. Research indicated that humanintervention on the Yellow River delta was successful, for the further implementation ofecological restoration in Yellow River delta wetland provided the theoretical basis andtechnical support, the artificial intervention ways mentioned above has importantpromotion value and broad application prospects.