Archive for 4月 2020

Home Archive for 4月 2020

28^th April2020

新加坡國家公園署2018年開發樹地圖（Tree Map）

新加坡的Tree Map (樹地圖) 網站可以讓民眾標記喜歡的樹及上傳🌳🌳照片樹沃客到目前為止替桃園、台中市調查記錄了超過100,000株樹木，希望未來臺灣也可以有這樣好用的平台，讓這些成果能被更多人使用😘 目前各縣市政府有在陸續整合資料及建置平台，期待早日完成上線！新加坡國家公園署2018年開發樹地圖（Tree Map）網站(https://www.nparks.gov.sg/trees)，記錄全國50多萬棵樹籍資料，讓民眾標記喜歡的樹、上傳更新這棵樹的照片，隨時追蹤。

27^th April2020

鹿角蕨分類青青小樹。多肉萌

By >樹沃客 with 0 Comments

鹿角蕨分類青青小樹。多肉萌資料來源:鹿角蕨分類青青小樹。多肉萌

27^th April2020

機械攀爬裝置 akimbo 發明者 Jaime merritt 專訪

By >樹沃客 with 0 Comments

機械攀爬裝置 akimbo 發明者 Jaime merritt 專訪 https://youtu.be/5b032aToyIM

27^th April2020

樹木的社會福利網白色山毛櫸 V Moravském krasu roste unikátní buk albín. Živí jej les

By >樹沃客 with 0 Comments

樹木的社會福利網白色山毛櫸 V Moravském krasu roste unikátní buk albín. Živí jej les 在捷克深山中，有非常特別的山毛櫸，它沒有葉綠素，以至於無法行光合作用。大約有千分之一山毛櫸是白化的，大多在一年內死亡。少部份白化山毛櫸，因旁邊的山毛櫸地下根接網幫助，提供養份，而能存活數十年資料來源: https://www.novinky.cz/veda-skoly/clanek/v-moravskem-krasu-roste-unikatni-buk-albin-zivi-jej-les-40321370?fbclid=IwAR0hTZH21lO45Fr_bZsSZR6W0eceRskDfJAtB28UDQqERZQTsLR5zedhNYc

27^th April2020

樹木最小臂理論 The Principle of Minimum Lever Arms

By >樹沃客 with 0 Comments

樹木最小臂理論 The Principle of Minimum Lever Arms 樹木會用最輕鬆的方式應對重力沒必要不會多出任何一點力量就像人提著水桶很辛苦直接把水桶，以有最小的臂舉去支撐這是最輕鬆的方式資料來源: https://link.springer.com/chapter/10.1007/978-3-642-61219-0_4

27^th April2020

你真幸運

By >樹沃客 with 0 Comments

你真幸運

27^th April2020

願主保佑修女

By >樹沃客 with 0 Comments

願主保佑修女

27^th April2020

The world's oldest, largest Cork Tree

By >樹沃客 with 0 Comments

The world's oldest, largest Cork TreeThe Whistler TreePortugal

27^th April2020

為松鼠打造餐桌

By >樹沃客 with 0 Comments

為松鼠打造餐桌

27^th April2020

植物燈泡 Isabelle Dt

By >樹沃客 with 0 Comments

植物燈泡 Isabelle Dt

27^th April2020

龍卷風的威力 How strong is a tornado?

By >樹沃客 with 0 Comments

龍卷風的威力 How strong is a tornado?

26^th April2020

亮點在保險桿貼紙 Look at the bumper sticker. tree rock

By >樹沃客 with 0 Comments

亮點在保險桿貼紙 Look at the bumper sticker. tree rock

25^th April2020

高大的樹木與建築奇觀的圖表 Eduard mielck - Die Riesen der Pflanzenwelt

By >樹沃客 with 0 Comments

高大的樹木與建築奇觀的圖表 Eduard mielck - Die Riesen der Pflanzenwelt 巨樹和建築物大小比較，圖下的大象與鯨魚看起來像是小不點西班牙的杜魯之樹 (Árboldel Tule)，樹幹週長 42公尺，它是如此之大，以至於最初被認為是多棵樹長在一起，但 DNA 測試證實它是一棵樹。猢猻木樹根有像駱駝背部。資料來源: https://www.atlasobscura.com/articles/chart-tallest-buildings-tallest-trees

25^th April2020

如何成為綠手指東京自耕農

By >樹沃客 with 0 Comments

如何成為綠手指東京自耕農資料來源: 東京自耕農 Leo's Tokyo Life

24^th April2020

德國人的務實，沒有極限，樹木受風力量公式

By >樹沃客 with 0 Comments

德國人的務實，沒有極限，樹木受風力量公式德國人作了以下裝置，直接讓樹木受風，進而導出樹木受風力公式 P為空氣密度，u為風速，a為樹冠截面積，cw為風阻系數

24^th April2020

樹木樹叉解決 tree fork

By >樹沃客 with 0 Comments

樹木樹叉解決 tree fork 樹木分叉出去時，有想過他的纖維是怎麼排例的嗎? A : 注重工程力學排例 - 這可以讓樹叉獲得最高的強度，但水份與養份無法運輸。 B : 注重水力傳送排例 - 解決了水份與養份運送問題，但樹枝沒有強度，分枝容易折斷。 C : 纖維互鎖排例 - 這同時有了力學上的強度，水份與養份可以運送。

23^th April2020

里約熱內盧植物園 Botanic Garden in Rio de Janeiro

By >樹沃客 with 0 Comments

里約熱內盧植物園 Botanic Garden in Rio de Janeiro

23^th April2020

三種類型的樹夾皮

By >樹沃客 with 0 Comments

三種類型的樹夾皮 A 嵌入式 : 樹皮完全被木質部所包圍，樹皮被塞在接合處。 B 杯形 : 樹皮週圍形成邊材，分叉的頂點為兩處邊材。 C 寬口形 : 樹皮在分叉的頂點處有相當大的寬度。 Figure 6.3: Three types of bark-included bifurcation found in hazel trees (yz plane view of internal structure) Diagrams and images defining three morphological types of bark-included junctions in hazel, based on observations of the fracture surfaces of such bifurcations perpendicular to the plane of the

21^th April2020

Banyan tree tunnel Stuart Florida

By >樹沃客 with 0 Comments

Banyan tree tunnel Stuart Florida

21^th April2020

樹冠的形狀大部份主要是由陽光和重力造成的，有些樹樹冠取決於這兩者的平衡而有特定形狀Tree crowns grow into self-similar shapes controlled by gravity and light sensing

By >樹沃客 with 0 Comments

樹冠的形狀大部份主要是由陽光和重力造成的，有些樹樹冠取決於這兩者的平衡而有特定形狀Tree crowns grow into self-similar shapes controlled by gravity and light sensing αp表示光照參數，αg表示重力參數，曲線下方深綠色的自然界理論上不會出現，因為這些樹冠形狀光照與重力之間狀態不會達成平衡 A set of crown shapes obtained from a numerical computation, varying αg and αp, and with γ = 0.01. Green shapes (above the curve) have converged towards a self-similar-one, whereas grey shapes have not converged. For each shape, the parameter values correspond to the grid intersection. (Online version in colour.)

達文西樹木法則 "all the branches of a tree at every stage of its height when put together are equal in thickness to the trunk." Da Vinci

Self-similarity. a Representation of the Strahler order of each branch for the tree illustrated in Fig. 4. b The number of branches, their mean length (unit L), area (unit L 2) and diameter (unit L) are plotted as a function of their Strahler order for the 999-year-old tree illustrated in Fig. 4 and in a. Error bars show standard deviations around these means. Solid lines are regression fits on the first 7 ranks. Open symbols connected by dotted lines represent the same quantities when the tree is only 25 years old. c Evolution of the branching ratio R n , length ratio R l and fractal dimension D = lnR n /lnR l during the lifetime of the same tree. Grey bars show the 80% confidence interval for D. d Branch tapering is illustrated by plotting, for each segment, the average distance from the foliages,

⟨ ℓ ⟩

Assessment of Leonardo’s rule of area conservation across branching nodes. For each node, the area ratio (i.e. the ratio between the total cross-sectional area of children segments and the parent area) is plotted as a function of the average distance

⟨ ℓ ⟩

⟨ ℓ ⟩ > 1.5

⟨ ℓ ⟩ > 10

⟨ ℓ ⟩ > 10

In his notebooks, Leonardo da Vinci observed that “all the branches of a tree at every stage of its height, when put together, are equal in thickness to the trunk”. Yet, the mechanisms underlying this Leonardo’s rule are still debated today. One hypothesis is that branches sense wind-induced loads and adjust their diameters to resist fracture, while keeping biomass investments to a minimum.

達文西樹木法則這個是真的，這是達文西在筆記本寫下的，事實上樹還真的是這樣，為什麼樹木會有這樣的規則呢 ?
500年過後，對這類解釋有兩種，第一種為水文，把樹枝看做河流，當河水流分流出去後，分流出去的總水量是一樣的。樹枝也傳送水的，很理所當然。第二種解釋和力學結構有關，樹木這樣生長可以用最少的材料來達成不錯的抗風效果，這是電腦模擬驗證的喔!
有不符合達文西樹木法則的情況嗎? 有的，可能有以下情況1年輕的樹枝，會大於下方母枝一點面積。2反應木不符合3樹木基部出來萌枝

資料來源:

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0093535

https://www.insidescience.org/news/uncovering-da-vincis-rule-trees?fbclid=IwAR2fJBSrbQqPReICOcLP4Q-apudZrWfW0RYDn5HJLyt7AMe6X8Zt4PGG5vQ

https://www.nature.com/articles/s41467-017-00995-6

Pages 1 of 30 12 3 4 5 6 7 8 9 Next Last

訂閱：文章 ( Atom )