Subjects: Biology >> Botany >> Applied botany submitted time 2018-10-26 Cooperative journals: 《广西植物》
Abstract： Dipterocarpus retusus Bl. is state’s key protected wild plant. It is the representative species in tropical rainforest of Southeast Asia. Our study aims to elucidate the community characteristics of Dipterocarpus retusus forest which has not yet studied before. Four community plots (30 m×30 m) and 20 population plots (10m×10m) were typically sampled in the Dipterocarpus retusus forest distributed in Niuluo River Natural reserve in Jiangcheng County. The height, DBH (diameter at breast height), numbers and community characteristic of all the spermatophyte species were recorded. We evaluated the distribution types, species diversity and population age structure. The results showed that: (1) 181spermatophyte species belonging to 143genera, 76 families were recorded. Dipterocarpus retusus community was dominated by tropical floristic elements, of which 58 families, 126genera and 162species were all belonging to tropical flora and the ratio were as high as 76.32%, 88.11% and 89.50%, respectively. (2) Species diversity indices are varied in different stand layers: Richness index and Shannon-Wiener diversity showed shrub layer＞tree layer＞herb layer, while Simpson index showed opposite trend shrub layer＜tree layer＜herb layer and Pielou index is similar in different stand. (3) Dipterocarpus retusus is the donimant species in the community with the highest important value of 26.85 in tree layer. (4) The age structure of Dipterocarpus retusus population had a positive pyramidal type which indicated that the populaiton structure is growing.
Subjects: Biology >> Botany >> Applied botany submitted time 2018-09-07 Cooperative journals: 《广西植物》
Abstract： Jasminum yuanjiangense is an narrowly distributed endemic species in Yuanjiang River Valley of Yunnan province. 4 sample plots, belongs to two vegetation types including dry-hot shrubs and savanna were typically selected in the distribution area of J. yuanjiangense. The population age structure and survival curves were created and the type of population structure were analysesd by Chen Xiaode's Quantification Method, and predicted population dynamics using time sequence model, and compared the population differences between different habitats. The results showed that: (1) The population of J. yuanjiangense presented as a growing type and tend to stable(Vpi’=0.0041). The populations had definite fluctuations during their growth dynamics, and the number of individuals in the pre-growth stage is more than that in the late growth stage. The survival curve of population approached to type Deevey-Ⅲ and Deevey-Ⅰ.The seedlings is abundant, but the mortality is high. The growth and development of individuals were limited from young to middle age. (2) The time sequence model predicted that the population of J. yuanjiangense was able to keep stable and the number of individuals would have a light rising tendency in the coming 2, 4 age classes.1 (3) The population structure of J.yuanjiangense varies greatly among different sites,But it can be roughly divided into two types according to its age structure. Sample plots 1, 2 and 4 (habitat 1) displayed growing type with Deevey-III survival curve, plot 3 (habitat 2) displayed stable type with Deevey-I survival curve. The habitat of stable type is more suitable for the growth of J ． yuanjiangense than the habitat of growing type.
Subjects: Agriculture, Forestry,Livestock & Aquatic Products Science >> Plant Protection submitted time 2018-07-18 Cooperative journals: 《广西植物》
Abstract： Survey on plant resources plays a basic role in studying plant systematics and floristic evolutionary history and affinities, which is one of the important tasks of plant research in China. Although China has a rich accumulation in plant resources investigation with Flora of China and local flora records, data on plant resources in some remote areas are still lacking. Actinodaphne lecomtei Allen, Cinnamomum ilicioides A. Chev. and Carya kweichowensis Kuang A. M. Lu ex Chang et Lu are reported with new distribution records by morphological comparison in southern Yunnan, China, respectively. A. lecomtei was previously recorded to be found in Sichuan, Guizhou, Guangdong (Ruyuan) and Guangxi, China, C. ilicioides to be endemic to Guangdong, Hainan, Guangxi, China, and northern Vietnam, C. kweichowensis to be distributedinAnlong,Wangmo,Cenheng,Xingyi ofGuizhouetc., China.The newdistributionrecordsofA.lecomtei andC. ilicioides complements theweak areas in China, and provide a datafor analyzing relationshipbetween original species with genera and the taxonomic study of Lauraceae in China. The new distribution record of C. kweichowensis provides a new case at the species level for confirming the connection between C. kweichowensis and Annamocarya sinensis, furthermore, providesgermplasmresourcesforthedevelopmentofC.cathayensisproductioninYunnan.
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-04-19 Cooperative journals: 《计算机应用研究》
Abstract： In the past, most of the traditional link prediction methods are oriented to the undirected network, in fact, most social networks are directional, and do not consider the duplication between the same node pair and the microscopic evolution information in the network, therefore they can not solve Link prediction in directed dynamic networks better. This paper focused on the directional network, the repeated edge information between the pair of nodes is transformed into the weight of the edge between the pair of nodes, then used the evolution model based on the triad motif, calculate the motif transformation probability matrix between the adjacent time slice in the move window, the probability matrix be analyzed by exponentially weighted moving average, and then it used the matrix to predict the chain edge in the network. This method not only makes full use of the network micro evolution information, but also solves the problem of overlapping edges in dynamic network. Experiments show that this method can get better results than Common Neighbor, Triad Transition Matrix and other methods in network with high Global Clustering Coefficient and high Average Degree．Therefore, this method can apply the network microscopic information to the link prediction better.
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