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Huo A.-D.,Chang'an University | Huo A.-D.,China Institute of Water Resources and Hydropower Research | Guan W.-K.,Desert Research Institute | Dang J.,Chang'an University | And 4 more authors.
Geomatics, Natural Hazards and Risk | Year: 2016

ABSTRACT: The torrential flooding and debris flow disasters associated with global climate change pose not only serious threat to individual lives and property, but also impact economic development. Accurately simulating flood scenarios can help to reduce the losses caused by torrential flooding and debris flow by making early warning, evacuation planning, and risk analysis possible. In this study, HEC-RAS software and HEC-GeoRAS module were employed in GIS (geographic information system) to simulate the flood overtopping in the Mengzong Gully of Batang River in flood scenarios occurring once in 20, 50, and 100 years, respectively. The simulated floods provided valuable information including scope and depth of submersion via 2D visualization. © 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.


Zhang S.,Northwest University, China | Zhang L.,Northwest University, China | Chai Y.,Northwest Institute of Forest Inventory | Wang F.,Northwest University, China | And 4 more authors.
Journal of Proteomics | Year: 2015

Ancient trees have an important value in humanities and history, and also have an important scientific value in the investigation of the decline and senescence mechanisms. Thus, we conducted an environmental stress study using ancient trees. To evaluate age-dependent changes in physiology and the leaf proteome, we assessed the low-temperature stress responses of 20±5-, 500±100- and 1200±. 200-year-old Platycladus orientalis (L.) samples obtained outdoors during winter. Several physiological parameters were evaluated. Leaf proteomes were obtained using two-dimensional electrophoresis gels, and 77 protein spots were identified successfully using MALDI TOF/TOF MS/MS. The majority of the identified protein species were classified into functional categories including defense/stress-related, energy and carbohydrate metabolism, photosynthesis, and hormone-related functions. A general reduction in the abundance of protein species was observed as the age of the studied trees increased; reduction in photosynthesis and defense/stress-related categories were particularly apparent in the leaves of ancient trees. However, the number of protein species with functions in energy and carbohydrate metabolism increased with age. An increase in the abundance of lipid metabolism and hormone-related protein species was a primary characteristic of the leaves of ancient trees under low-temperature stress during winter. These results improve our understanding of the biochemical mechanisms of stress responses in ancient trees. Biological significance: Low temperature is the most common meteorological challenge in the study area. For evergreen plants, low-temperature stress has a great impact on the leaves of ancient P. orientalis. Thus, we conducted an environmental stress study using ancient trees. Recently, various studies were carried out in ancient trees. However, no information is available on the molecular mechanisms of defense to low-temperature stress in ancient trees. Therefore, this original study comprises the following differential proteomic analysis of ancient P. orientalis: (1) age-dependent changes in the physiology and leaf proteome are evaluated under low-temperature stress to (2) understand the differences in metabolic responses between ancient and adult trees under low-temperature stress during winter. This analysis will provide an understanding of the complex physiological changes that occur in ancient trees. The results suggest that certain identified proteins can be used as markers of low-temperature stress in ancient P. orientalis. © 2015 Elsevier B.V.


Guan J.,Chinese Ministry of Water Resources | Guan J.,University of Chinese Academy of Sciences | Zhou H.,Northwest Institute of Forest Inventory | Deng L.,Northwest Agriculture and Forestry University | And 4 more authors.
Journal of Forestry Research | Year: 2015

We used the forest inventory data of Gansu Province, China to quantify carbon storage and carbon density changes by regional forest cover and by typical forest types in 1979–2006. Total forest area increased from 1.77 × 106 ha in 1979 to 2.32 × 106 ha in 2006, and the forest carbon storage, estimated by the continuous biomass expansion factor method, increased from 83.14 to 100.66 Tg, equivalent to a carbon accumulation rate of 0.0071 Tg per year during the period. Mean carbon densities were 44.83–48.50 t ha−1 and the values decreased slightly over the time period. Natural forests generated greater carbon storage and density than did plantations. By regression analysis, forest stand age was an important parameter in carbon density studies. We developed various regression equations between carbon density and stand age for major types of natural forests and plantations in the region. Our results can be used for proper selection of re-forestation species and efficient management of young and middle-aged forests, offering great potential for future carbon sequestration, especially in arid and semi-arid regions. © 2015 Northeast Forestry University and Springer-Verlag Berlin Heidelberg


Tang L.,Northwest University, China | Li T.,Northwest Institute of Forest Inventory | Li D.,Northwest University, China | Meng X.,Northwest University, China
Scientific World Journal | Year: 2014

The elevational distribution of plant diversity is a popular issue in ecology and biogeography, and several studies have examined the determinants behind plant diversity patterns. In this study, using published data of the local flora of Taibai Mountain, we explored the effects of spatial and climatic factors on plant species richness. We also evaluated Rapoport's elevational rule by examining the relationship between elevational range size and midpoint. Species richness patterns were regressed against area, middle domain effect (MDE), mean annual temperature (MAT), and mean annual precipitation (MAP). The results showed that richness of overall plants, seed plants, bryophytes, and ferns all showed hump-shaped patterns along the elevational gradient, although the absolute elevation of richness peaks differed in different plant groups. Species richness of each plant group was all associated strongly with MAT and MAP. In addition to climatic factors, overall plants and seed plants were more related to area in linear regression models, while MDE was a powerful explanatory variable for bryophytes. Rapoport's elevational rule on species richness was not supported. Our study suggests that a combined interaction of spatial and climatic factors influences the elevational patterns of plant species richness on Taibai Mountain, China. © 2014 Lili Tang et al.


Liu Z.,Northwest University, China | Liu Z.,Northwest Institute of Forest Inventory | Yue M.,Northwest University, China
Chinese Journal of Ecology | Year: 2014

Kingdonia uniflora is an endemic endangered clonal species in China and shows a patchy distribution pattern on small scales within its distribution area. In the present study, using Digital Photography Technology, Geographic Information System and Digital Plant Canopy Imager, we analyzed the dynamics of sunfleck, canopy structure, soil physical and chemical properties in forest within the K. uniflora distribution on the north slope of Mt. Taibai in China. The results showed that the number and area of sunfleck and the sunfleck index in sampling plots were significantly lower with than without K. uniflora. There were significant differences in canopy structure between the two types of plots. The transmission coefficients for diffuse penetration, the transmission coefficients for radiation penetration and the canopy gap area in the plots were smaller with than without K. uniflora, while the leaf area index was vice versa. In addition, there were no statistically significant differences in measured soil physical and chemical properties among the two kinds of plots. Therefore, we speculate that sunfleck is likely one of leading factors determining the distribution of K. uniflora on the north slope of Mt. Taibai.


Guan J.,Chinese Ministry of Water Resources | Guan J.,University of Chinese Academy of Sciences | Zhou H.,Northwest Institute of Forest Inventory | Deng L.,Northwest Agriculture and Forestry University | And 4 more authors.
Journal of Forestry Research | Year: 2015

We used the forest inventory data of Gansu Province, China to quantify carbon storage and carbon density changes by regional forest cover and by typical forest types in 1979–2006. Total forest area increased from 1.77 × 106 ha in 1979 to 2.32 × 106 ha in 2006, and the forest carbon storage, estimated by the continuous biomass expansion factor method, increased from 83.14 to 100.66 Tg, equivalent to a carbon accumulation rate of 0.0071 Tg per year during the period. Mean carbon densities were 44.83–48.50 t ha−1 and the values decreased slightly over the time period. Natural forests generated greater carbon storage and density than did plantations. By regression analysis, forest stand age was an important parameter in carbon density studies. We developed various regression equations between carbon density and stand age for major types of natural forests and plantations in the region. Our results can be used for proper selection of re-forestation species and efficient management of young and middle-aged forests, offering great potential for future carbon sequestration, especially in arid and semi-arid regions. © 2015, Northeast Forestry University and Springer-Verlag Berlin Heidelberg.


Li J.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Li J.,University of Chinese Academy of Sciences | Cao Y.-H.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Liang T.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | And 2 more authors.
Chinese Journal of Ecology | Year: 2016

Eco-redline is supposed to be the minimum area that should be strictly protected to ensure the regional eco-health and eco-service sustainability. To draw the eco-redline scientifically would be an effective way to improve eco-function. In this paper, we summarized the previous studies and rebuilt the eco-redline framework including eco-function redline, environment redline and resource redline by considering eco-function, environment and resource categories, respectively, which could be worked on time, space and management. The three redlines together constitute the urban eco-redline framework system. By taking eco-function redline as example, and from the aspect of ecosystem itself, we proposed a method to demarcate eco-function redline based on the pattern, process, function and amenity of urban system. Using Jixian County in Tianjin as an example, we draw out the regional eco-function redline with a total area of 11425 hm2, which is mainly distributed in north mountain and river basins of Jixian. Combined with the regional characteristics and the corresponding eco-redline area, we also put forward some corresponding control measures. The exploration of our study in theory, method, model and application provides theoretical and methodical supports for further study on eco-redline in future. © 2016, Editorial Board of Chinese Journal of Ecology. All Rights Reserved.


PubMed | Northwest Institute of Forest Inventory and Northwest University, China
Type: | Journal: TheScientificWorldJournal | Year: 2014

The elevational distribution of plant diversity is a popular issue in ecology and biogeography, and several studies have examined the determinants behind plant diversity patterns. In this study, using published data of the local flora of Taibai Mountain, we explored the effects of spatial and climatic factors on plant species richness. We also evaluated Rapoports elevational rule by examining the relationship between elevational range size and midpoint. Species richness patterns were regressed against area, middle domain effect (MDE), mean annual temperature (MAT), and mean annual precipitation (MAP). The results showed that richness of overall plants, seed plants, bryophytes, and ferns all showed hump-shaped patterns along the elevational gradient, although the absolute elevation of richness peaks differed in different plant groups. Species richness of each plant group was all associated strongly with MAT and MAP. In addition to climatic factors, overall plants and seed plants were more related to area in linear regression models, while MDE was a powerful explanatory variable for bryophytes. Rapoports elevational rule on species richness was not supported. Our study suggests that a combined interaction of spatial and climatic factors influences the elevational patterns of plant species richness on Taibai Mountain, China.

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