In recent years, the decrease trend of the Yellow River runoff appears and the Yellow River does not reach often to the Bohai Bay since 1970’s because of huge amount of water uses for irrigation at midstream.
The Xiaolangdi Reservoir is situated on the key position where can control the water and sediment entering into the lower reaches. It has controlled 91% of the river runoff and almost 100% of the river sediment.
As the intensity of El Nio becomes stronger,the precipitation and runoff decrease drastically. The strong El Nio events would bring about a river flux reduction of 25.59%(147.17 10~(8)m~(3)) in annual average.
A significant positive correlation was observed between the annual flow and the size of forest harvesting, which resulted in the increase of river runoff after forest harvesting.
The correlation analyis for the relation between the amount of ice and snow of the South Pole and the amount of annual runoff at Sanmenxia Station on the Yellow River are presented in the paper based on the data since 1764, it is found that there are more notable reverse correlation between them and the relation of about one year time of lag is the most close. Comparing with changes of the amount of runoff of the Yellow River in history during several main wet and dry periods, it is correspondence to the pe...
Based on monthly mean flow-off data at Tang Naihai and Ge Zhouba . the characteristics of the temporal variations of flow off are analysed. The results indi- cate that there are periodic variations of high flow and low flow, and there are different characteristics in different places. At Tang Naihai , there are the dominant periods of 7.4 and 18.5 years, and there are the dominant periods of 15. 14 and 7.07 years at Ge Zhouba. The duration of flow-off departure (the signs of departure are same) at Tang Naib...
In mid May and the beginning of August every year,the abundance indexes of both eggs/larvae and the juveniles were surveyed in the spawning sites and habitats of penaeid shrimp in the Bohai Bay,the relationship of the egg abundance index ( S t ) and the recruitment ( R t ) in Ricker Model is: R t=aS te -bS t ,and the obtained parameters are: a =29 2243, b =0 069, R 2=0 47, P <0 005. The results indicated that the egg abundance of penaeid shrimp had the determinant effect on t...