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Research on Eco-physiological Characteristics and Their Wind-break and Sand-fixing Effects of Two Artemisia Species

Author: ZhangDeKui
Tutor: NiuJunYi；WangJiHe
School: Gansu Agricultural University
Course: Crop
Keywords: Oil of Artemisia Artemisia arenaria Distribution pattern Niche Branching member Sand-fixation plants Windbreak and sand
CLC: X173
Type: Master's thesis
Year: 2007
Downloads: 225
Quote: 1
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Abstract


Oil the Artemisia and sand Artemisia are Asteraceae Artemisia semi-shrubs, plants, sand-fixation plants in arid desert region, desert vegetation in constructive species and dominant species in the desert area of ??ecological and environmental protection and agricultural production plays an extremely important role. Study oil of Artemisia and Artemisia arenaria physiological and ecological characteristics of its sand-fixing effect, practical significance for the further use of the resources of the desert plants the regional desertification governance, development of agricultural and livestock production. At the same time has the important academic value for further study of desert vegetation restoration and reconstruction. From the oil of Artemisia Artemisia arenaria Sand burial depth on seed germination Germinetion laws of growth and development, photosynthesis and transpiration characteristics, population distribution patterns, population niche Branching member features and sand-fixing effect, The main results are as follows: 1 oil of Artemisia and sand Artemisia seed weight 0.311g and 0.547 g. Seeds buried in the sand a depth of 0 ~ 4mm, germination rate and germination rate greater than 60% sand burial depth from 6mm to 8mm, the germination rate and germination rate decreased rapidly, between 4 ~ 20mm, the germination rate and emergence The rate increase in the depth of the buried sand decreased, and the germination rate and germination rate of value with the increase of burial depth and the widening gap between burial depth greater than 20mm, the seeds could not germinate emergence. Oil Artemisia Artemisia arenaria in the desert region of the physical climate close to the date of occurrence, began to germinate from mid-March to early November to stop growing, growing season so 230d accumulation of nutrients in the process of growth and development of vegetative shoots, not death after wintering The second year of growth and development, reproductive branches bear fruit, as the seeds mature dry death, reproductive shoot growth only 1a. Oil Artemisia Artemisia arenaria Diurnal Variation curve trend showed a single peak, and the photosynthetic rate of change was a straight up or down trend with the increase or decrease of the photon density, photosynthetic peak day Zhongyou Artemisia than sand Artemisia photosynthetic peak late oil of Artemisia in 11:00 h, peak for 21.2272μmol · m -2 · s -1 , sand Artemisia 9:00 h, peak 20.8348μmol · m -2 · s -1 , the net photosynthetic rate of the two plants were dropped quickly after the peak. Day with photon density increase or decrease in the photosynthetic rate of the oil of Artemisia value rise or fall times than sand Artemisia night, photosynthetic rate value overall oiled sand Artemisia Artemisia higher than. 4. Diurnal variation of transpiration rate of the oil of Artemisia bimodal curve, two peaks appeared at 9:00 h and 13:00 h, transpiration rate values ??were 21.258 mol · m -2 · s -1 and 24.404 mol · m -2 · s -1 ; Sand Artemisia unimodal curve peaks at 13:00 h transpiration rate value of 16.444 mol · m -2 · s -1 . 30.38% of the oil of Artemisia transpiration rate variations than sand Artemisia large. 5 by population point pattern distribution analysis and variance / mean ratio analysis of oil Artemisia and Artemisia arenaria population distribution pattern conclusion consistent distribution of individuals in the populations of oil of Artemisia and sand Artemisia horizontal space types are cluster distribution. Flowing from the sand, semi-fixed sand dune to fixed Saudi oil of Artemisia niche breadth values ??were 0.051,0.194,0.224; the Sand Artemisia niche breadth values ??were 0.499,0.206,0.035; different successional stages differences in niche breadth they are also great differences between niche overlap with other species, the oil of Artemisia large value niche overlap with other species in the fixed sand, sand Artemisia ecological and other species in flowing sand niche overlap value; between the same species on the niche overlap values ??along with a corresponding change in the development and changes of the vegetation successional stages. 7 oil Artemisia Artemisia arenaria one, two, three branches are the type of secondary branching angle (the branching angle range from 50o ~ 60o), only the tip shoots branching the weak branching angle type ( branching angle between 35o ~ 50o), the growth of the branches can be extended more fully to the resource space; oil of Artemisia Sand Artemisia branches stretching from the three branches to a branch presented a weakening trend, shoot length from three level branches to a branch gradually shorter, oil of Artemisia levels branches corresponding branch length grow Artemisia, sand,. Oil Artemisia Artemisia arenaria each component, the moisture content of the leaf component is much larger than the other components; sticks components of the dry weight / fresh weight ratio than the other components of the large, main function of dry matter accumulation of old branches of the branch members The ratio of maximum support and extend functionality of the old branch plants is the largest. Oil Artemisia Artemisia arenaria individual assigned different heights at ground biomass varied oil Artemisia aboveground biomass is mainly concentrated in the 0 ~ 50cm height 30 to 40cm height at maximum biomass; biological sand Artemisia the amount of dispersion in different heights of 10 to 100cm, 70 ~ 80cm at the height of the biomass reaches the maximum, the spacing between the layers of sand Artemisia shoots than ordosica, but the total number of branches less than oil Artemisia. 10. Obvious oil Artemisia Artemisia arenaria individual sand-fixing effect, individuals after the distance range of 0 ~ 300cm, 20cm and 50cm height at the wind speed decreased significantly, especially 20cm height wind speed decreased most significantly, both after the plants 50cm at a minimum, followed by a slow increase. In different height wind speed curve similar to oil of Artemisia lower wind speed is significantly stronger than the sand Artemisia. Oil of Artemisia and Artemisia arenaria communities in sand-fixing effect, in particular, a significant reduction of the near-surface wind speed near the ground, in the semi-fixed sandy land and fixed sandy 20cm height compared to the same flow Saudi wind speed reduced by 76.5% and 86.0%, respectively, reduced by 58.7% and 56.3%, respectively, in the 200cm height wind speed. 200cm height wind speed of the flow of Saudi 6.5m · s -1 , fixed sandy no wind erosion occurs, semi-fixed sandy sediment transport capacity of 1.83 g · cm -1 · h -1 , only to flow Saudi 57.18g · cm -1 · h a -1

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