Currently, transforming the mode of forest management and developing multiple forest management practices are actively encouraged in China. As one forest management type, ginseng cultivation under larch plantations ha...Currently, transforming the mode of forest management and developing multiple forest management practices are actively encouraged in China. As one forest management type, ginseng cultivation under larch plantations has been developed significantly in the east of Liaoning Province. However, research on the influence of the ecological environment for this mode of production is still deficient. Based on this, our study compares the plant diversity and soil properties in the ginseng cultivation under larch plantations(LG) with larch plantations(LP) and natural secondary forests(SF). First, we randomly selected three plots for each of the three stand types which have similar stand characteristics; then, we carried out a plant diversity survey and soil sampling in each of the nine plots. The results show that no significant difference was found in plant diversity between LG and LP, but theevenness of herbs was significantly lower in LG than LP. No obvious changes in soil physical properties were found in LG, but a significant decrease in most of the soil nutrient content was presented in LG. Furthermore, we found a correlation between plant diversity(H') and soil properties in the three kinds of stand types, especially between herbaceous plant diversity and soil properties. We conclude that ginseng cultivation under larch plantations has no obvious effect on plant diversity, except the herbaceous evenness. Soil fertility can be depleted significantly in LG, but physical structures are not affected. Moreover, maintaining the diversity of herbaceous plants and controlling the density of ginseng cultivation in LG by farmers are important for the ecological environment. Based on this study and its good comprehensive benefits and with the support of policy, we think this forest management type should be promoted moderately in the region.展开更多
Restriction site amplified polymorphism (RSAP) was used, for the first time, to analyze the genetic structure and diversity of four, mainly cultivated, varieties of the brown alga, Saccharina japonica. Eighty-eight sa...Restriction site amplified polymorphism (RSAP) was used, for the first time, to analyze the genetic structure and diversity of four, mainly cultivated, varieties of the brown alga, Saccharina japonica. Eighty-eight samples from varieties "Rongfu", "Fujian", "Ailunwan" and "Shengchanzhong" were used for the genetic analyses. One hundred and ninety-eight bands were obtained using eight combinations of primers. One hundred and ninety-one (96.46%) were polymorphic bands. Nei's genetic diversity was 0.360, and the coefficient of genetic differentiation was 0.357. No inbreeding-type recession was found in the four brown alga varieties and the results of the "Ailunwan" variety using samples from 2 years showed that the variety was becoming less diverse during the selection inherent in the breeding program. Genetic diversity and cluster analyses results were consistent with these genetic relationships. The results show the RSAP method is suitable for genetic analysis. Continuous inbreeding and selection could reduce the genetic diversity effectively; therefore periodical supervision is required.展开更多
基金financially supported by the research on soft science of forestry(2014-R05)consulting project of the Chinese Academy of Engineering(2013-XZ-22)
文摘Currently, transforming the mode of forest management and developing multiple forest management practices are actively encouraged in China. As one forest management type, ginseng cultivation under larch plantations has been developed significantly in the east of Liaoning Province. However, research on the influence of the ecological environment for this mode of production is still deficient. Based on this, our study compares the plant diversity and soil properties in the ginseng cultivation under larch plantations(LG) with larch plantations(LP) and natural secondary forests(SF). First, we randomly selected three plots for each of the three stand types which have similar stand characteristics; then, we carried out a plant diversity survey and soil sampling in each of the nine plots. The results show that no significant difference was found in plant diversity between LG and LP, but theevenness of herbs was significantly lower in LG than LP. No obvious changes in soil physical properties were found in LG, but a significant decrease in most of the soil nutrient content was presented in LG. Furthermore, we found a correlation between plant diversity(H') and soil properties in the three kinds of stand types, especially between herbaceous plant diversity and soil properties. We conclude that ginseng cultivation under larch plantations has no obvious effect on plant diversity, except the herbaceous evenness. Soil fertility can be depleted significantly in LG, but physical structures are not affected. Moreover, maintaining the diversity of herbaceous plants and controlling the density of ginseng cultivation in LG by farmers are important for the ecological environment. Based on this study and its good comprehensive benefits and with the support of policy, we think this forest management type should be promoted moderately in the region.
基金Supported by the National Special Research Fund for Non-Profit Sector(No.200805075)the Shandong Foundation for Development of Scienceand Technology, China (No.2007GG10005018)+2 种基金the Genetically Modified Organism Technology Major Project (No.2009ZX08009-100B)the National High Technology Research and Development Program of China(863 Program) (Nos.2010AA10A401,2012AA10A406)the National Agricultural Transformation (No.2010GB23600666)
文摘Restriction site amplified polymorphism (RSAP) was used, for the first time, to analyze the genetic structure and diversity of four, mainly cultivated, varieties of the brown alga, Saccharina japonica. Eighty-eight samples from varieties "Rongfu", "Fujian", "Ailunwan" and "Shengchanzhong" were used for the genetic analyses. One hundred and ninety-eight bands were obtained using eight combinations of primers. One hundred and ninety-one (96.46%) were polymorphic bands. Nei's genetic diversity was 0.360, and the coefficient of genetic differentiation was 0.357. No inbreeding-type recession was found in the four brown alga varieties and the results of the "Ailunwan" variety using samples from 2 years showed that the variety was becoming less diverse during the selection inherent in the breeding program. Genetic diversity and cluster analyses results were consistent with these genetic relationships. The results show the RSAP method is suitable for genetic analysis. Continuous inbreeding and selection could reduce the genetic diversity effectively; therefore periodical supervision is required.
