Study On The Adaptation To Coastal Saline Soil And Application Of Two Specie Nitraria In Yellow River Delta

The Yellow River Delta, one of the three bayou deltas, has great potential of land exploration and use. The region is close to Bohai Sea, where the high soil salinity, bad soil structure, and fragile entironment greatly restrict the effective use of land resources and ecological construction. According to the actual conditions of the Yellow River delta and characteristics of the coastal saline soil, we used Nitraria tangutorum from Qing Hai and the local Nitraria sibirica pall as experimental materials, and studied the seedling breeding technology, salt-tolerance ability and the improving effects on the coastal saline soil of the two kinds of Nitraria according to three kinds of tests: brine irrigating, field salt-tolerant and seedling test. This study takes theories to biology improvement of coastal saline and sustainable exploitation and use of saline soil resources.The results showed that the two kinds of Nitraria were both adapted to grow in the coastal saline soil of Yellow River delta, had better salt-tolerance ability and improvements on the coastal saline soil. Compared with Nitraria tangutorum, the effect of Nitraria sibirica on the entironment was higher, but the nutritive value of Nitraria sibirica was lower. The main results were as follows:1,Seeding experiments in many ways proved that seeding in the container and field were the best for Nitraria tangutorum, while seeding by layering and ramet or in container were fit for Nitraria sibirica.2,The results of brine irrigating and field salt-tolerant tests indicated that the salt-tolerance ability of Nitrari tangutorum was 1.5%, and that of Nitraria sibirica was 1.8% in the coastal saline soil of Yellow River delta.3,It had significant desalting effects on the saline soil after two years of planting the two Nitraria in the coastal saline soil. In the 0-40 cm layer of mild, moderate and severe saline soil where Nitraria tangutorum were planted, the average desalination rate were 25.2%,42.8%,40.7% separately;and in the 0-40 cm layer of mild, moderate and severe saline soil where Nitraria sibirica were planted, the average soil desalination rate were 38.2%,48.9%,51.09%. The effects of the two plants on the desalination of severe saline soil were the best, and the effects on the mild saline soil were worst. But the soil desalination rate of the saline soil where Nitraria sibirica was planted was higher than where Nitraria tangutorum was planted.4,After planting the two Nitraria in the coastal saline soil, the soil organic matter content significantly increased in the 40 cm soil layer, and the contents of the available N, the available P and the available K also increased. The effects of the two Nitraria on the contents of the soil organic matter, the available N, the available P and the available K in different saline soil were: mild saline soil > moderate saline soil > severe saline soil. Compared with Nitraria tangutorum, the effect of Nitraria sibirica on the increasing of soil nutrient was much better.5,The soil physical properties obviously became better after planting the two kinds of Nitraria in the coastal saline soil, such as soil bulk density reducing, soil porosity improving and pH value slightly dropping. The improving effect of Nitraria sibitica on the soil physical properties was better than Nitraria tangutorum.6,The field test indicated that the two Nitraria advanced soil desalting, improved the soil physical properties, soil fertility and ecological environment on the one hand, and it also had higher economic yield on the other hand by planting the two kinds of Nitraria in Yellow River delta where the soil salt content is 1%. The results indicated that there were high contents of sugar, vitamin C and many kinds of amino acids in the fruit. And it has greater development space and higher economic benefit to plant the two kinds of Nitraria in the Yellow River Delta.