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Search Results: 1 - 10 of 24037 matches for " JIANG Fengqi "
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Jiang Fengqi,

生态学报 , 1982,
Abstract: By applying the method of quantification theory I , five mathematical equations for estimating the biomass of natural Caragana microphylla brush have been established. Those models may be used for calculating fresh and dry weight of brush, dry weight of, leaves, tender and large branches. Average height, average diameter at ground, number of plouts and growth state are the four factors affec-tiag biomass. Among those factors, the number of plants plays the most important role.
Eco-value level classification and ecosystem management strategy of broad-leaved Korean pine forest in Changbai Mountain

ZHENG Jingming,JIANG Fengqi,ZENG Dehui,

应用生态学报 , 2003,
Abstract: To realize the sustainable management of forest ecosystems, we should explicitly clarify the types and differences of the ecosystem services provided by different ecosystems under different conditions, with rethinking about the value of forest ecosystems; then solid management strategies and measurements will be enacted and applied to achieve the objects. The broad-leaved Korean pine forest (BLKPF) in Changbai Mountain is a unique and important forest type in China, owing to its many important ecosystem services such as preventing soil erosion, regulating climates, nutrient cycling, providing wood and non-timber forest products, etc. This paper is a preliminary study on the management strategy of BLKPF on the basis of analyzing the characters of the ecosystems and the relative importance of services they provided in this region. Based on the latest research of ecosystem services of BLKPF in Changbai Mountain, an idea of eco-value level (EVL) was introduced, and accordingly, management strategies were summarized by adopting the advanced theories in ecosystem management science and by analyzing field survey data. EVL means the relative amount of the value of ecosystem services provided by certain ecosystem, which can indicate the difference between services in given objects. The EVL classification of BLKPF implies the relative amount of the eco-value of different ecosystems including virgin forest, secondary forest, forest with human disturbance, and man-made forest in the clear-cutting sites. Analytical Hierarchical Processing method was used to formulate the equation for EVL index. Eight factors, namely, slope, soil depth, stability of soil maternal material, coverage of above-ground canopy, species diversity, regeneration rate of the stand, life span of dominant tree species, and intensity of human disturbance were chosen to build the formula. These factors belonged to three aspects affecting ecosystem services including the physical environment, community, and disturbance regime, and their selection and scaling were based on the previous studies on the BLKPF. The equation of EVL index (EI) was expressed as: EI = 0.542A1 + 0.171A2 + 0.072A3 + 0.067B1 + 0.043B2 + 0.014B3 + 0.010B4 + 0.081C1. According to the range of EI, ecosystems were classified into three types: low EVL type with EI from 1.000 to 1.874, medium EVL type with EI 1.874-2.749, and high EVL type with EI 2.749-3.623. Typical plots were surveyed and scaled with EI, and the predominant characters of each EVL type were summarized. Most forests of high EVL type were those in sites at high risk of soil erosion and hard to recover after disrupted. Forests of medium EVL type were those with worse community structure and composition, and were disturbed by human activities in relative steep sites. Forest of low EVL type were those in plane site with serious disruption or some young man-made stands. Based on the analyses of the characters of these three types, different management strategies
Decline of protective forest and its prevention strategies from viewpoint of restoration ecology: Taking Pinus sylvestris var. mongolica plantation in Zhanggutai as an example

JIANG Fengqi,ZENG Dehui,YU Zhanyuan,

应用生态学报 , 2006,
Abstract: Aimed at the decline of protective forest in China, and applying the key principles of restoration ecology, such as ecological succession, disturbance, and population density, etc. , this paper assessed the rationality of designing elements of protective forest in decision-making level, and analyzed its relationships with the decline of the forest, taking Pinus sylvestris var. mongolica plantation in Zhanggutai sandy land as an example. It was considered that the disagreement of large-scale afforestation with succession climax in regional scale was aberrant to the ecological principles, and resuhed in the aberrancy of the objectives, steps, species composition, and stand density of protective forest establishment, being the main cause of protective forest decline. Mismanagement and frequent natural and human disturbances were also the important causes for the decline. Three strategies for preventing the decline, i. e. , better understanding damaged ecosystems, increasing material and energy input, and overcoming disturbances were put forward, and the objectives of restoring vegetation, judgment of climax for ecological succession, and application of plagioclimax in establishing artificial vegetation were discussed.
Comprehensive evaluation and selection of urban eco-engineering virescent trees in Shenyang City

LU Min,JIANG Fengqi,LI Yingjie,

应用生态学报 , 2004,
Abstract: Urban virescence eco-engineering is the core of urban eco-environmental construction,which can promote urban sustainable development.In urban virescence eco-engineering,the comprehensive evaluation of ecological adaptability and ecological effect of urban plants is the scientific basis of rational application and selection of urban garden plants.The ecological effect and integrative functions of urban virescence eco-engineering depend upon the selection and layout of garden plants.Using the methods of garden expert consultation and evaluation,this paper established systematically integrative evaluation and application indices of virescence plants in Shenyang City,from the aspects of ecological adaptability,ecological effect,beautification effect,resistance to plant diseases and insect pests,anti-pollution and economic results.According to garden experts evaluation and location of Shenyang,200 sorts of virescence trees were evaluated and classified on the basis of the comprehensive evaluation system of virescence trees,and using cold resistance,drought resistance,barren resistance,plant diseases and insect pests resistance,anti-pollution,ornamental quality and ecological effects as the indexes.The results showed that the number of first rank trees was 58,the second was 93,the third was 38,and the fourth was 11,ranked by integrative performance.
Vegetation restoration in western Liaoning hilly region:A study based on succession theory and degradation degree of ecosystem

DU Xiaojun,JIANG Fengqi,JIAO Zhihua,

应用生态学报 , 2004,
Abstract: Based on the analysis of vegetation succession in western Liaoning hilly region,and by the method of Cluster Analysis with some habitat indexes of different succession stage,this paper quantitatively measured the degradation degree of degraded ecosystems in this region.The results showed that the average dissimilarities between natural Quercus forest,natural Chinese pine (Pinus tabulaeformis) forest and Populus-Quercus forest in Nanliuzhangzi forestry centre and Chinese pine plantations in Niuheliang region and Qitian forestry centre were 0.655,0.665,2.029 and 3.919,respectively,and as a whole,the dissimilarities represented the places of the forests in the process of ecosystem succession /degradation.It was also showed that most habitats were degraded to the stage between shrubbery and pioneer arbor forest,and closer to the succession stage of pioneer arbor forest.Some suggestions were made for the management of the existing plantation and the construction of mixed forest,e.g.,to increase the proportion of shrubbery and pioneer arbor species,especially that of nitrogen fixation tree species.The plant species list of several main vegetation types in western Liaoning we offered could provide scientific reference for the vegetation restoration and the management of pure Chinese pine plantation in this region.
Influence of shelterbelts structure on snow distribution pattern in shelternets in Northeast China

FAN Zhiping,ZENG Dehui,CHEN Fusheng,ZHU Jiaojun,JIANG Fengqi,SHA Jianguo,

应用生态学报 , 2004,
Abstract: The amount of snow that falls in farmland during winter in Northeast China is the important source of soil water in farmland, so the influence of shelterbelt structure on snow distribution pattern is the key problem in order to adjust structure of shelterbelts according to porosity in management practice. Based on snow depths in shelternets composed of shelterbelts with three levels of porosity, which were shelternet No. 1, shelternet No. 2, and shelternet No. 3, the snow distribution patterns in farmland were studied. The results showed that the structure of shelternet had great influence on snow distribution in farmland. With different levels of porosities, spatial pattern of snow distribution were obviously different in three shelternets. The more variant in porosity, the more obvious difference in snow distribution pattern, and the best uniformity of snow distribution appeared in shelternet with porosity of phi 2w = 0.579, phi 2s = 0.268, in which snow depth in farmland was relative even and the variability of snow depth was the least. Consequently, the relationship of porosity of shelterbelt with snow distribution pattern could be used to guide structure adjustment and optimization management of shelterbelts.
Optimization of spatial arrangements and patterns for shelterbelts or windbreaks

ZHU Jiaojun,JIANG Fengqi,FAN Zhiping,ZHOU Xinhua,

应用生态学报 , 2003,
Abstract: Spatial arrangements and patterns of shelterbelts or windbreaks are the key factors influencing the shelterbelt structures, shelter benefits, and shelterbelt sustainability. In order to keep the shelter benefits and achieve the sustainability of shelterbelts, it is necessary to keep the reasonable arrangements and patterns in spatiality and the continuation in time. Based on the investigations on the shelterbelts, which were established in 1992 as the models in Shuangjingzi Township, Changtu County, Liaoning Province, and combined with the experiences and practices of shelterbelt management, the authors studied and summarized the arrangements and patterns of shelterbelts, which included the direction of a single shelterbelt and shelterbelt networks, the arrangement of tree composition in a shelterbelt, and the mixture of tree species for shelterbelts. Additionally, the spacing intervals between shelterbelt and the spatial patterns for regional shelterbelts were also discussed. The results indicated that the direction of both single shelterbelt and shelterbelt networks should be perpendicular to the disaster winds. It is better for the structure of a shelterbelt to arrange the trees in triangle form in a shelterbelt. According to the edge effect, the tree species which grow slowly should be arranged in the edge lines, but the tree species which grow fast should be arranged in the inner lines of the mixed shelterbelts. Optimal spacing intervals between windbreaks could be predicted from the indices of a given windbreak structure (porosity), percentage of desired wind speed reduction, and tree growth model (model for determining initial protective maturity age). The patterns of shelterbelts in large scale should be evaluated and arranged according to the principles of landscape ecology. The results mentioned above would provide the evidences for shelterbelt sustainable management.
Self thinning of even aged pure plantations of Pinus sylvestris var. mongolica on sandy soil

ZENG Dehui,JIANG Fengqi,FAN Zhiping,DU Xiaojun,

生态学报 , 2000,
Abstract: Since density dependent mortality is caused by the increase of tree size,it is more natural to choose an indicator of the size to express the relationship between the number of trees and the size.We chose the total stand basal area as the indicator of the size,and established an equation relating the number of trees to the total basal area of even aged pure plantations of Pinus sylvestris var. mongolica on sandy soil during their self thinning.We reviewed the -3/2 power law of plant self thinning,and suggested that although there is no satisfying evidence to support the accuracy of the slope of -3/2,it may be regarded as an ideal slope,and that with a view of various realities,we allow the existing of difference of the practical slope to the ideal one.
Decline regularity and causes of Pinus sylvestris var.mongolica plantation on sandy land

WU Xiangyun,JIANG Fengqi,LI Xiaodan,XUE Yang,QIU Sufen,

应用生态学报 , 2004,
Abstract: The study showed that the decline of Pinus sylvestris var. mongolica plantation out of its natural distribution area was a phenomenon of premature senility. The infected harm of shoot blight was the direct cause of Pinus sylvestris var. mongolica dying, but wasn't the basic reason. The decline of Pinus sylvestris var. mongolica was caused by the interaction of biological and other factors, which was "the third disease" beyond infectious and non-infectious diseases, namely, "decline disease of forest". Climate difference, improper management, unbalanced usage of soil water, and high content of N settled from air were the inducing factors, among which, climate difference and unbalanced usage of soil water were the main ones, while insect harm and shoot blight were the promoting factors.

Jiang Fengqi,Guo Shanhe,Zhang Tieqiang,Shen Xuanguo,

电子与信息学报 , 1994,
Abstract: This paper proposes a new arterial pulse detector using optic fiber sensor, and describes the theory, experimental set-up and experimental results of the apparatus. The optic fiber sensor is the detecting part that can detect the arterial pulses. The optical signal of the arterial pulses will be transformed into electrical signal. After signal processing, the image of arterial pulses is displayed on an oscilloscope.
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