| Eucommia ulmoides Oliv. blong to the family Eucommiaceae, genus Eucommia Oliver, it is said to be’living fossil’. As a unique rare and precious species in China, it’s already well known for the medicine function. But as the deeper understanding of E. ulmoides for people, found that it can be used in all parts, not only has broad medical value, also has the value of agricultural, ecological, and industrial, etc. China discovered the duality of eucommia rubber and plastic and invented the orchard cultivation mode first, that laid the foundation for the development of E. ulmoides industry at present stage. At present, every provinces have begun to speed up the development of modern industry of E. ulmoides.Cili county is one of the earliest county for developing the E. ulmoides industry in Hunan province and whole country, with the characteristics of long cultivation history, vast area and good mass base. But the cultivation status of is not clear now, and the existing resources whether meet the development demands of E. ulmoides flower, rubber and such industries is also uncertain. This study was carried out the survey which focus on the E. ulmoides resource status and how the soil pH, organic matter, and N, P, and K effects on the growth condition of E. ulmoides. According to the results of the survey, marked a group of plus tree, measured some indexes, and the main conclusions as following:(1) Cultivation area and distribution characteristics of E.ulmoides in Cili county: The existing E. ulmoides planting forests covers an area of 4969.1 hm2, and it’s given priority to man-made forest. The distribution characteristic was dotted or linear distribution along mountainous and hilly.(2) Age structure of E.ulmoides:the mainly forest of E.ulmoides were adult forest (age 11-30 years), covers an area of 3570.7 hm2, accounting for 72% of the total area. Followed by the young forest (age 10 years or less), covers an area of 933 hm2, accounted for 19% of the total area, finally was mature forest (age 30 or more years), covers an area of 465.4 hm2.(3) Growth condition:the growth condition of E.ulmoides were closely related with altitude, rainfall, and soil conditions. The average annual growth rate of E.ulmoides was larger at an altitude of 500-700 m, and the growth situation became worse at an altitude of more than 1200 m or below 100m. Basic rainfall that E.ulmoides needs was 1000-2000 mm every year, within the scope of the moderate rainfall, it’s growth rate was higher. On the other hand, the growth rate was significantly lower. The growth rate of E.ulmoide was faster under the good soil conditions, such as in Lingyang town, Cili county, E.ulmoide, which was 18 years old, average diameter at breast was 13 cm, tree height was 7 m. The growth rate was lower under the poor soil, such as in Nanshanping, the average diameter and tree height of 10 years old tree were less than 3 cm and 2 m.(4) The mainly application form were medicinal forest and soil and water conservation forest. Leaves and fruit as the by-products. Lake of fine varieties with plentyful rubber, flower, and fruit.(5) The soil pH was significantly related to the growth of E. ulmoides. Eucommia bark has certain salinity resistance. It can live in strong acidity (pH 4.0) or alkaline (pH 7.6) of soil environment, but poor growth. Growth was the best number 1,2,3, respectively for the weak acid soil environment (pH 6.5-7.5).(6) The growth of the soil organic matter content and E. ulmoides relationships: Organic matter content has relationship to the growth of the eucommia bark, too high (8,48.5 g/kg) or low (4,8.4 g/kg) were not conducive to the growth of E. ulmoides. The tree height and diameter at breast height (DBH) of sample 8 was 5.1 m and 9.2 cm, and sample 4 was 8.1 and 11.2cm. The best tree height growth were sample 1,2, and 3. Their organic matter content were 14.6 ±1.8 g/kg,23.8 ± 2.8 g/kg, and 2.8 ±4.2 g/kg, respectively.(7) The content of soil available nitrogen, phosphorus, and kalium (N, P, K) were significantly related to the growth of diameter and height of the bark E. ulmoides. Too high (8 sample,255.2 g/kg) or low (9 sample,47.5 g/kg) was not conducive to the growth of E. ulmoides. The tree height and DBH of sample 8 were 5.1 m and 9.2 cm, and sample 9 were 5.6 m and 10.0 cm. The best tree height and DBH were sample 1, 2, and 3. And their effective nitrogen content were 80.1±8.8g/kg,90.5±9.8g/kg, 9.8± 10.1 g/kg, respectively. By comparing the effective phosphorus can be found and effective nitrogen for smaller effect of E. ulmoides tree height and DBH.(8) On the basis of resource survey, through the density of flowering, flower, flowers with nutritional analysis preliminary chose three champion tree of male E. ulmoides; Through the seed density, abortive rate, gel content of preliminary chose two champion tree of female E. ulmoides. |
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