Advanced Materials Research Vols. 726-731

Abstract: Niche characteristics of nineteen main associated tree populations in moso bamboo mixed forests in Luoboyan Natural Reserve were investigated. The results show that associated populations of Sarcandra glabra, Ilex purpurea and Eurya japonica, with high important values have great capacity of adapting to environment and also have broader niche breadths. Liquidamba formosana seldom appear as associated trees and have narrow niche breadth. Castanopsis fargesii, Engelhardia fenzelii, Castanopsis kawakamii, Schima superba, Nyssa aquatic and Carpinus turczaninowii have close niche breadth and similar distribution range within the community. Ilex purpurea- Castanopsis fargesii, Ilex purpurea-Engelhardia fenzelii, Engelhardia fenzelii-Liquidamba formosana, Castanopsis kawakamii-Dendropanax dentiger, Rhododendron pulchrum-Schima superba, Dendropanax dentiger-Castanopsis lamontii and Castanopsis lamontii-Carpinus turczaninowii have high niche overlaps which prove that species having similar or same circumstances demands high niche overlap indexes. Species with broader niches have more chances for niche overlap with other species. Sarcandra glabra distributes widely and has broad niche breadth but low overlap index with other species, which indicates that species with broad niche breadth is not inevitable to have broad niche overlap with other species.

Abstract: This paper simple introduced back propagation (BP) neural networks, and constructed a dynamic predict model, based on it to predict forest disease and insect and rat pest. Then it analyzed and simulated with the BP neural network model with the data produced in the recent ten years. The result indicated that the BP neural network model is reliable for predicting the forest disease and insect and rat pest. The method provides scientific foundation for the forestry management of studied area.

Abstract: Through field investigation and room experiment, the characteristics of the rainfall partition in the canopy layer of six forest types beside Songhua River were studied. The canopy interception of the rainfall was different in six forest types; from maximum to minimum was Quercus monglica forest, Pinus koraiensis plantation, Tilia mandshurica forest, Fraxinus mandshurica-Larix olgensis forest, Fraxinus mandshurica-Populus davidiana forest and Juglans mandshurica forest. There were significant linear correlation between through fall and precipitation and significant exponential correlation between canopy interception and precipitation in studied forest types; The stem flow ratio to gross rain fall ranged from 0.74% to 16.61% in six forest types, from maximum to minimum was Juglans mandshurica forest, Quercus monglica forest, Pinus koraiensis plantation, Fraxinus mandshurica-Larix olgensis forest, Fraxinus mandshurica-Populus davidiana forest and Tilia mandshurica Forest. In the same precipitation condition, the stem flow ratio to gross rain fall should be affected negatively by canopy size.

Abstract: The year 2011 is the International Year of the Forest-a time when people around the world are encouraged to pay special attention to the importance of forest ecosystems and the goods as well as ecological services they provide to sustain societies and economies. As the one of the giant of forest recourses consumption, China has the responsibility and obligation to made untiring efforts and unselfish contribution for the development of the world forestry. Research indicates that although Chinese forest area, forest growing stock as well as forest coverage continue to grow, there will still have a huge gap of wood demand because of the countrys large area and population. Many problems of Chinese forestry are pressing for solution in order to be on the path of sustainable forest management. In particular, through the development of plantations, reducing demand by enhancing the comprehensive use of timber with advanced science and technology, and advocating saving timber and recycling. Chinese experiences and lessons are also enlightenment to other countries.

Abstract: Through the manner of field investigation and room experiments, by using software SPSS 13.0, software ArcGis 9.3 and geostatistical analysis tool, the spatial heterogeneity of the soil bulk density under virgin Pinus koraiensis forest, Betula platyphylla and Pinus koraiensis mixed forest (Pinus koraiensis natural regeneration), Betula platyphylla and Pinus koraiensis mixed forest (Pinus koraiensis planted) and pure Pinus koraiensis plantation were studied. The characteristics of the spatial heterogeneity of the soil bulk density under different forest types were different, the spatial heterogeneity of the soil bulk density under four forest types were influenced by random factors, but the auto relationship part of the soil bulk density spatial heterogeneity under Betula platyphylla and Pinus koraiensis mixed forests were bigger, and the change distance was smaller than that under pure Pinus koraiensis plantation. The spatial distribution pattern of the soil bulk density under Betula platyphylla and Pinus koraiensis mixed forests was superior to that under pure Pinus koraiensis plantation. The results would provide a theory basis for the recovery and the sustainable management of the Pinus koraiensis forest.

Abstract: Rhizoctonia solani Kühn is the causal pathogen of tobacco target spot, a serious fungal disease of tobacco that severely impairs yield and quality in northeast China. The objective of this study was to characterize isolates of R. solani from tobacco in China. Among 58 Rhizoctonia isolates examined, all of them were multinucleate. Phylogenetic analyses and hyphal anastomosis criteria suggest that the isolates belonged to R. solani anastomosis group (AG) 3. Target spot isolates from Liaoning province formed a single phylogenetic group together with tomato isolates of R. solani AG-3 from Japan and are more closely related to R. solani AG-3 isolates in tomato and potato than that in tobacco from USA. Pathogenicity test for each isolates was fulfilled using a method of inoculating tobacco leaves from plants grown for 8 weeks (cv. NC89).

Abstract: In this study, two encoding invertase inhibitors (INH) named as MeINH1 and MeINH2 were isolated from cassava (Manihot esculenta Crantz). TheMeINH1 contains a 583 bp fragment in length and codes a region of 172 amino acids; and the MeINH2 contains a 538 bp fragment in length and codes a region of 169 amino acids. The amino acid sequence analysis showed that both MeINH1 and MeINH2 have typical structure of invertase inhibitor proteins with a N-terminal signal peptide, four conserved cysteine residues and two disulfide bridges, respectively; whereas, they showed low homology to other organisms. This research provides a foundation for further study of the cassava INH.

Abstract: Analysis of gas exchange and determination of chlorophyll fluorescence parameters in leaves of three tree species including Aesculus chinensis, A. octandra and A. hybrida were conducted under field conditions and then comparison was carried out. The results showed that the light compensation point (LCP) was significantly different among the three tree species, of which the LCP of A. chinensis with 12.53 μmol·m^-2·s^-1 that of the lowest was notable lower than that of the other two species (36.11 and 46.41 μmol·m^-2·s^-1respectively). On the other hand, the light saturation point (LSP) of the three tree species also showed remarked different and the LSP of A. chinensis was 1475 μmol·m^-2·s^-1 which was dramatic higher than that of the other two species respective to 1366.67 and 1025 μmol·m^-2·s^-1. Beside, the maximum net photosynthetic rate (MNPR) was different too, MNPR of A. chinensis was 9.47μmol CO ₂·m^-2·s^-1which was higher than the other two species (5.91 and 2.30 μmol CO ₂·m^-2·s^-1 respectively), indicating A. chinensis had a higher photosynthetic capacity and stronger utilization ability for light energy. Moreover, the electron transport rate (ETR) of A. chinensis was higher than A. octandra and A. hybrida, the ETR of the former was 55.800 that were 1.33 and 1.44 times of the later two respectively. Quantum yield of PSII photochemistry (Ф_PSII) in A. chinensis was higher than A. octandra and A. hybrida, the Ф_PSII of the former was 0.470 that were 1.21 and 1.15 times of the later two respectively. Furthermore, the photochemical quenching (qP) of A. chinensis was 0.975 much higher than A. octandra and A. hybrida respective to 1.10 and 1.10 times of the later two respectively. These three photochemical parameters with dramatic different among the three different tree species suggested A. chinensis had a high activity of electron transport and conversion efficiency for light energy.

Abstract: Near-infrared spectroscopy (NIRS), with the characteristics of high speed, non-destructiveness, high precision and reliable detection data etc., is a pollution-free, rapid, quantitative and qualitative analysis method. A new approach for the discrimination of the ingredients of corn (moisture, oil, protein, starch) by means of NIR spectroscopy (1100-2498 nm) was developed in this work. The relationship between the reflectance spectra and the ingredients of corn was established. The data were spilt into training and testing subsets by sample set partitioning based on join x-y distance (SPXY),the spectral data was compressed by orthogonal signal correction (OSC), wavelength was selected by backward interval partial least-squares (biPLS),the 60 samples to build PLS mode, the model was used to predict the varieties of 20 unknown samples. The standard error of prediction (SEP) was 0.173; the relative error of prediction (PRE) was 0.55%; the correlation coefficient (R) was 0.98. The way to detect the ingredient of food is simply, reliable.

Abstract: The classification of the understory industries, the developing significance of the understory forage plants and the researching status quo at home and aboard on forage plants briquetting machine are introduced briefly. On this basis, the development of briquetting machine for understory forage plants in the southern hilly region is introduced emphatically. The pressure is applied stationary with two cylinders and feed quality can be guaranteed perfectly, Constant temperature system is installed in the box then the feed with paste flavor; at the same time the developing prospects of the briquetting machine and understory economy are also well expected.