臺灣博碩士論文加值系統

植物族群的遷徙及擴張，主要是由其種子之長距離飄散(Long-Distance Dispersion)決定。尤其由風力承載的種子，需要較為複雜的模式才能準確描述其飄散行為。本研究目的為利用拉格朗日隨機飄散模式(Lagrangian Stochastic Dispersion Model)，模擬種子於森林流場中飄散軌跡，結合紊流動能消散率間歇性，探討種子在不同大氣狀況下之飄散情形；並改變各項模式參數 (地表摩擦速度、釋放高度以及種子終端速度)，檢視其對種子長距離飄散之影響，評估各項因素之相對重要性。
研究結果顯示，不穩定大氣狀況及消散率間歇性皆會增加種子長距離飄散能力，且消散率間歇性增幅較大。不穩定大氣更可以加強間歇性造成的垂直飄散速度驟增，使更多粒子被抬升至冠層以外，傳輸至較遠地區；同時在極不穩定大氣(h/L = -1)時會使近距離密集落地位置往前靠近釋放來源。在加入紊流間歇性下，穩定大氣長距離飄散能力和中性大氣時相近，並會使近距離密集落地位置往後遠離種子釋放來源。另外，無論在何種大氣狀況下，增加地表摩擦速度、釋放高度以及較小的終端速度皆可使種子長距離飄散能力增加 (其中以釋放高度的改變對加入紊流間歇性之模式結果影響最大)；且在不穩定狀態下，這些長距離飄散能力的增加程度會被放大。

The migration and expansion of plant species are determined by the Long-Distance Dispersion (LDD). The more sophisticated mechanistic dispersal model is needed especially for the LDD of the wind-driven seeds. This study simulated the seed dispersion trajectories in the canopy turbulence by using the Lagrangian Stochastic Dispersion Model under different atmospheric stabilities in conjunction with the effect of the intermittency of the turbulent kinetic energy dissipation rate. Also, the effects of friction velocity, seed release height and seed terminal velocity are studied.
The results showed that both the unstable atmosphere and the inclusion of the dissipation rate intermittency in the model could increase seeds’ LDD. The number of seeds which escape the canopy volume by the dissipation intermittency is increased under unstable atmosphere, hence more seeds can be transported to the further distance. Under the strong unstable atmosphere, the peak location of dispersal kernel tends to be closer to the source when the dissipation intermittency is included. The ability of LDD is similar under neutral and stable atmospheric condiotions, and the peak location will be further away from the source under stable condiotion. Also, no matter which atmospheric condition, higher friction velocity, higher seed release height and lower seed terminal velocity all increase the LDD of seeds. The change of LDD due to the change of the friction velocity, seed release height, and the seed terminal velocity, would be enhanced under the unstable condition.

摘要 I
Abstract II
目錄 III
圖目錄 V
表目錄 VI
符號表 VII
一、 緒論 1
二、 研究方法 5
2.1 Lagrangian Stochastic Dispersion Model 5
2.2 種子特性 6
2.2.1 種子速度 6
2.2.2 Crossing Trajectories 7
2.3 紊流流場特性 7
2.3.1 Flow Statistics 7
2.3.2 紊流間歇性(Dissipation Intermittency) 10
2.4 種子飄散機制模式之解析解 11
三、 模式設定 13
3.1 模式設定 13
3.2 敏感度分析 14
四、 結果與討論 15
4.1 消散率間歇性及大氣穩定性比較 15
4.2 各參數對種子飄散之影響 17
4.2.1 摩擦速度(u*) 17
4.2.2 釋放高度(zr) 18
4.2.3 終端速度(wg) 18
4.2.4 相對影響 19
五、 結論 20
參考文獻 21
附錄A. 種子粒徑大小對水平方向速度之影響 42
附錄B. 平均流場剖面 45
附錄C. 瞬時紊流動能消散率(εt)之對數常態分佈特性 49
附錄D. 種子飄散解析模式與LSDM比較 51

Arritt, R. W., Clark, C. A., Goggi, A. S., Sanchez, H. L., Westgate, M. E., & Riese, J. M. (2007). Lagrangian numerical simulations of canopy air flow effects on maize pollen dispersal. Field crops research, 102(2), 151-162.
Brown, J. K., & Hovmøller, M. S. (2002). Aerial dispersal of pathogens on the global and continental scales and its impact on plant disease. Science, 297(5581), 537-541.
Chamecki, M., & Meneveau, C. (2011). Particle boundary layer above and downstream of an area source: scaling, simulations, and pollen transport. Journal of Fluid Mechanics, 683, 1-26.
Csanady, G. T. (1963). Turbulent diffusion of heavy particles in the atmosphere. Journal of the Atmospheric Sciences, 20(3), 201-208.
Duman, T., Katul, G. G., Siqueira, M. B., & Cassiani, M. (2014). A Velocity–Dissipation Lagrangian Stochastic Model for Turbulent Dispersion in Atmospheric Boundary-Layer and Canopy Flows. Boundary-layer meteorology, 152(1), 1-18.
Duman, T., Trakhtenbrot, A., Poggi, D., Cassiani, M., & Katul, G. G. (2016). Dissipation Intermittency Increases Long-Distance Dispersal of Heavy Particles in the Canopy Sublayer. Boundary-Layer Meteorology, 159(1), 41-68.
Gleicher, S. C., Chamecki, M., Isard, S. A., Pan, Y., & Katul, G. G. (2014). Interpreting three-dimensional spore concentration measurements and escape fraction in a crop canopy using a coupled Eulerian–Lagrangian stochastic model. Agricultural and Forest Meteorology, 194, 118-131.
Greene, D. F., & Johnson, E. A. (1992). Fruit abscission in Acer saccharinum with reference to seed dispersal. Canadian Journal of Botany, 70(11), 2277-2283.
Katul, G. G., Porporato, A., Nathan, R., Siqueira, M., Soons, M. B., Poggi, D., ... & Levin, S. A. (2005). Mechanistic analytical models for long-distance seed dispersal by wind. The American Naturalist, 166(3), 368-381.
Kolmogorov, A. N. (1941, January). The local structure of turbulence in incompressible viscous fluid for very large Reynolds numbers. In Dokl. Akad. Nauk SSSR (Vol. 30, No. 4, pp. 301-305).
Kolmogorov, A. N. (1962). A refinement of previous hypotheses concerning the local structure of turbulence in a viscous incompressible fluid at high Reynolds number. Journal of Fluid Mechanics, 13(01), 82-85.
Kuparinen, A., Markkanen, T., Riikonen, H., & Vesala, T. (2007). Modeling air-mediated dispersal of spores, pollen and seeds in forested areas. Ecological modelling, 208(2), 177-188.
Kuparinen, A., Katul, G., Nathan, R., & Schurr, F. M. (2009). Increases in air temperature can promote wind-driven dispersal and spread of plants. Proceedings of the Royal Society of London B: Biological Sciences, rspb20090693.
Nathan, R., & Muller-Landau, H. C. (2000). Spatial patterns of seed dispersal, their determinants and consequences for recruitment. Trends in ecology & evolution, 15(7), 278-285.
Nathan, R. (2006). Long-distance dispersal of plants. Science, 313 (5788), 786-788.
Nathan, R., Katul, G. G., Bohrer, G., Kuparinen, A., Soons, M. B., Thompson, S. E., ... & Horn, H. S. (2011a). Mechanistic models of seed dispersal by wind. Theoretical Ecology, 4(2), 113-132.
Nathan, R., Horvitz, N., He, Y., Kuparinen, A., Schurr, F. M., & Katul, G. G. (2011b). Spread of North American wind‐dispersed trees in future environments. Ecology Letters, 14(3), 211-219.
Obukhov, A. M. (1962). Some specific features of atmospheric turbulence. Journal of Geophysical Research, 67(8), 3011-3014.
Pan, Y., Chamecki, M., & Isard, S. A. (2013). Dispersion of heavy particles emitted from area sources in the unstable atmospheric boundary layer. Boundary-layer meteorology, 1-22.
Pazos, G. E., Greene, D. F., Katul, G., Bertiller, M. B., & Soons, M. B. (2013). Seed dispersal by wind: towards a conceptual framework of seed abscission and its contribution to long‐distance dispersal. Journal of Ecology, 101(4), 889-904.
Pope, S. B., & Chen, Y. L. (1990). The velocity‐dissipation probability density function model for turbulent flows. Physics of Fluids A: Fluid Dynamics, 2(8), 1437-1449.
Rannik, Ü., Markkanen, T., Raittila, J., Hari, P., & Vesala, T. (2003). Turbulence statistics inside and over forest: influence on footprint prediction. Boundary-Layer Meteorology, 109(2), 163-189.
Rodean, H. C. (1996). Stochastic Lagrangian models of turbulent diffusion (Vol. 45). Boston: American Meteorological Society.
Sawford, B. L., & Guest, F. M. (1991). Lagrangian statistical simulation of the turbulent motion of heavy particles. Boundary-Layer Meteorology, 54(1), 147-166.
Soons, M. B., Heil, G. W., Nathan, R., & Katul, G. G. (2004). Determinants of long‐distance seed dispersal by wind in grasslands. Ecology, 85(11), 3056-3068.
Trakhtenbrot, A., Nathan, R., Perry, G., & Richardson, D. M. (2005). The importance of long‐distance dispersal in biodiversity conservation. Diversity and Distributions, 11(2), 173-181.
Thomson, D. J. (1987). Criteria for the selection of stochastic models of particle trajectories in turbulent flows. Journal of Fluid Mechanics, 180, 529-556.