Primary Study On Bio-ecological Characteristics Of Four Chenopodiaceae Plants

It is drought and rare rain in arid area. Intensive evaporation results in general salinization. Therefore, the functions and structures of the eco-system in arid area are negatively effected and the development of agriculture are seriously hindered,so it is a realistic problem that salinization should be treated with different measures. In this paper, the bio-ecological characteristics of indigenous halophytes: Salsola implicata, Suaeda linifolia, Halocnemum strobilaceum and Kalidium foliatum will be studied in order to explore the mechanisms of plants tolerance and to get the theory and measures for treating salt soil and applying halophytes. we can draw conclusions as follows:(1) The number of Suaeda linifolia seedlings in high salt soil is big,but the death rate of it is high and the death of seedlings is different at different time and space. The causes of survival seedlings death are that salt crust has negative effects on seedlings, but the salt glove or salt sheath is helpful to grow for seedlings. Besides, a specific salt-tolerant mechanism of Suaeda linifolia seedlings has been found. Soil water has a serious effect on Salsola implicata seedlings.(2) The relationships between root length of Salsola implica, Halocnemum strobilaceum and Kalidium foliatum seedlings and soil salt concentration are significant, but the relationship between the number of lateral roots of Suaeda linifolia seedlings is significantly negative, the tall, fresh weigh and the number of leaves of Suaeda linifolia and Salsola implicata are almost normal distribution in the range of soil salt concentration, the optimum salt concentration is 0.27-0.89% and 0.16-0.36% respectively; The growth of Halocnemum strobilaceum and Kalidium foliatum seedlings are poor in high salt soil. but good in low salt soil (<0.43 %),compared with their perennial, the salt-tolerant adaptability of Halocnemum strobilaceum and Kalidium foliatum seedlings is weak. (3) The average axial roots length of Suaeda linifolia is 31cm,lateral roots are distributed from 15cm to 35cm under the surface, the majority of roots is thin (<0.05cm); The average axial roots length of Salsola implicata is 47.3cm,lateral roots in the range from 20cm to 53cm,the majority of it is thin(0.03cm);The roots of Halocnemum strobilaceum horizontally stretched to about 1m,the average diameter of roots is within 0.6 cm, root coverage is about 1.40m2.But the roots of Kalidium foliat- um is beyond to 1.4m,the range of root diameter is within 1.5m,root coverage is 1.96 m2.The relationship between the root density and soil salt concentration is extremely significant, the root weigh and soil salt concentration is significant, the root density are related with soil water and pH, but the relationship is not significant. Bedsides, the changes of soil temperature have effect on roots distribution.(4) The water content of external layer of root xylem of Kalidium foliatum is highest. In the range of root diameter from 0.3cm to 0.5cm,the most roots diameter are between 0.3cm and 0.5cm.But the water content of external layer of root xylem of Halocnemum strobilaceum is highest in the range from 0.5cm to 0.6cm ,the water content of xylem is highest, so the most roots diameter is from 0.5cm to 0.6cm.(5) SO42- and Cl- contents of Suaeda linifolia seedlings are the same as that of soil, Mg2+ is more. but SO42- and Cl- contents of Salsola implicata seedlings are 1.5 times and 2 times more than that of soil seperatively.Mg2+ and Ca2+contents of it are respectively 20 times and 5 times more than that of soil. But in the whole, the ions contents of Halocnemum strobilaceum and Kalidium foliatum is very low. These indicate that the relationship between the ion contents of plants and that of soil is not significant.(6) With the development and growth of plants, the natural water saturation deficiency (N.W.S.D.) and the leaf succulence of Salsola implicata and Suaeda linifolia changes drastically, strong drought resistance is indicated, but that of Halocnemum strobilaceum and Kalidium foliatum is not...