Research Of Climate Change In The Yellow River Delta And Its Impacts On Wetland

This article uses11meteorological stations of temperature, precipitation, evaporation, windspeed and relative humidity data of climate factors. Combined with the climate change trendanalysis methods, analysis the climate elements in the year1961-2013in the Yellow River delta,then obtain climate changing tendency of the Yellow River Delta in recent53years. At last,analysis the impacts of climate change on Wetland in the Yellow River delta. The mainconclusions are as follows:1. The annual variation of climate elements: The temperature in the Yellow River deltashowed a clear upward trend. The other climatic factors showed a declining trend overall. Theprecipitation and relative humidity of the annual variation showed obvious fluctuation. An annualvariation of evaporation and wind speed showed a continued downward trend.Seasonal variation of climate elements: The temperature in the four seasons appears a risingtrend. The average temperature in winter has the largest increase and the temperaturein summer has the smallest rate. The average seasonal precipitation showed an increasingtrend in the spring, the other seasons showed a downward trend. The average precipitation insummer decreased most rapidly. The average evaporation of each season hasa decreasing trend, the maximum was in the winter, and minimum was in the spring. The averagewind speed of each season has a decreasing trend, the maximum was in the spring, and minimumwas in the autumn. The average relative humidity of each season has a decreasing trend, themaximum was in the autumn, and minimum was in the spring.The monthly variation of climate elements: The annual temperature range in the YellowRiver Delta area is large. The temperature reached the highest in July,which is26.62℃, and theminimum temperature is-2.98℃in January. The Yellow River Delta region uneven distribution,and each month varies greatly, which concentrated in January to August. The evaporation of eachmonth has some significant differences, which the maximum was in June and the minimum was inJanuary. The average wind speed in each month was in the form of saddle shaped, andthe maximum was in April. The relative humidity changes in the larger each month, whichthe maximum was in August and the minimum was in April. From January to August, the YellowRiver Delta area the high temperatures, abundant rainfall, exuberant evaporation, highrelative humidity and small wind speed.2.The correlation with the climatic factors: the average annual temperature was negatively related with other climatic factors and had the strongest correlation with annual average windspeed; the average annual precipitation was negatively related with both annual averagetemperature and annual evaporation, reflected a positive correlation with the annualaverage wind speed and average relative humidity and showed the strongest the correlation withannual average relative humidity; the annual average evaporation was positive related withannual average wind speed and the correlation was strongest, showed a negative correlation withannual average temperature, annual precipitation and annual mean relative humidity; the annualaverage wind speed showed negative correlation with average annual air temperature andthe correlation is strongest, showed a positive correlation with annualprecipitation, evaporation and annual average relative humidity; the average annual relativehumidity was negatively related with both annual average temperature and annual evaporation,reflected a positive correlation with both the average annual precipitation and annualaverage wind speed, showed the strongest the correlation with the average annual precipitation.3. The impact of climate change on wetland: correlation of the Yellow River Delta area ofeach wetland area and climate elements of the annual average value is very high. The greycorrelation degrees of climatic factors are: the average annual precipitation>average annualtemperature>average annual relative humidity> the average annual wind speed> annualevaporation. Climate change in the Yellow River Delta area, especially the temperature andprecipitation changes, will cause changes in the area of phenology, and effect the wetland cropgrowth, result in changes in biodiversity, wetland vegetation types and structure, impact onwetland carbon sequestration.