[Effects of Land Use Change on Constitution, Stability, and C, N, P Stoichiometric Characteristics of Soil Aggregates in Southwest China Karst].

Responses of soil aggregate stability and nutrient stoichiometry to land use change are of great significance to the protection and restoration of fragile ecosystems. In order to explore the influence of the law of land use change on soil aggregate stability and C, N, and P nutrient stoichiometric characteristics in the karst ecosystem of Southwest China, a typical region of the Southwest China Karst was selected as the study area. A series of sample plots were established for the seven typical land use types, and the constitution; stability; and C, N, and P contents and stoichiometric ratios of soil aggregates were studied.

[Soil available nitrogen and phosphorus contents and the environmental impact factors across different land use types in typical karst rocky desertification area, Southwest China.].

In this study, we collected soil samples from four different land use types (forest land, shrub land, grassland and abandoned land) in Huajiang valley of Guizhou Province, a typical karst rocky desertification area in Southwest China. Correlation analysis and redundancy analysis were used to examine the distribution of available nitrogen (N) and available phosphorus (P) in diffe-rent soil layers from 0 to 30 cm and the relationships between soil environmental factors (soil physical indexes, organic carbon components, electrochemical properties, metal oxides and enzyme activities) and the contents of available N and available P. The results showed that the concentrations of soil total N, total P, available N, available P decreased significantly with the increases of soil depth.

Cluster analysis of karyotype similarity coefficients in (Berberidaceae): insights in the systematics and evolution.

In order to evaluate the genome evolution and systematics, karyotype analysis of mitotic metaphase chromosomes in 51 taxa of and two species of was conducted. The 53 taxa were clustered, based on their karyotype similarity coefficients. Results showed that the 53 taxa studied were all diploid with 12 chromosomes (2 = 2 = 12).

[Effects of land use change on soil organic carbon and its components in karst rocky desertification of southwest China].

Soil organic carbon (SOC) is the dynamic medium of carbon transfer and the main pathway of carbon transfer in the karst ecosystem. SOC and its components are the important parts in soil carbon cycling of karst ecosystem. However, few studies have focused on SOC and its components in the karst ecosystem.

[Influence of Land Use Change on Litter and Soil C, N, P Stoichiometric Characteristics and Soil Enzyme Activity in Karst Ecosystem, Southwest China].

In this study, the litter and soil under four typical land use patterns of primary forest, shrub, grassland, and sloping land in Huajiang Karst Gorge in Guanling, Guizhou Province, were used to study the effects of land use change on the carbon(C), nitrogen(N), and phosphorus(P) stoichiometry characteristics of karst plant litter and soil as well as the effects on soil enzyme activities and their driving mechanism in Southwest China. The results showed significant differences in the litter-soil C, N, and P contents and soil enzyme activities among the four land use types. Compared with other regions, the litter and soil showed a pattern of high C, low N, high P and low C, low N, high P, respectively.

Morphological, physiological, cytological and phytochemical studies in diploid and colchicine-induced tetraploid plants of Fagopyrum tataricum (L.) Gaertn.

Background: Tartary buckwheat are very popular as an important functional food material and its cultivation is very widespread in our whole world, but there obviously lack works in the researches of genetic breeding for agricultural and medicinal utilization. The aim of this study is to obtain good germplasm resources for agricultural and medicinal use of tartary buckwheat (Fagopyrum tataricum) by inducing the tetraploid plants.

Results: Four cultivars of F.

The cytology, isozyme, HPLC fingerprint, and interspecific hybridization studies of genus epimedium (berberidaceae).

104 samples from 27 accessions belonging to 12 species of genus Epimedium were studied on the basis of cytology observation, POD (i.e., peroxide) isozyme, high performance liquid chromatography (i.