関連する実験動画

Updated: Jul 12, 2026

Reconstructing Terrestrial Paleoclimate and Paleoecology with Fossil Leaves Using Digital Leaf Physiognomy and Leaf Mass Per Area
10:14

Reconstructing Terrestrial Paleoclimate and Paleoecology with Fossil Leaves Using Digital Leaf Physiognomy and Leaf Mass Per Area

Published on: October 25, 2024

南西の砂漠のホロセンの森林地帯

T R VAN Devender

    Science (New York, N.Y.)
    |October 14, 1977
    PubMed
    まとめ

    米国南西部の砂漠は,冬の降水量が減ったために8,000年前に森から砂漠へと変化した. この気候変動は,氷河の融解が気象パターンに影響したため,世界的な傾向に遅れをとった.

    関連する概念動画

    Introduction to Wood01:19

    Introduction to Wood

    Wood, derived from trees, is a versatile and widely used construction material. Trees feature a trunk surrounded by a protective layer of dead bark. Beneath this outer layer lies the living bark, followed by the cambium, and then the sapwood which transitions into heartwood as it matures. At the center of the trunk is the pith. The age of a tree can be discerned by examining its growth rings, which are concentric bands visible in the trunk's cross-section.
    The structural integrity of the wood...
    Global Climate Change01:50

    Global Climate Change

    Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
    Habitat Fragmentation02:31

    Habitat Fragmentation

    Habitat fragmentation describes the division of a more extensive, continuous habitat into smaller, discontinuous areas. Human activities such as land conversion, as well as slower geological processes leading to changes in the physical environment, are the two leading causes of habitat fragmentation. The fragmentation process typically follows the same steps: perforation, dissection, fragmentation, shrinkage, and attrition.
    Softwoods and Hardwoods01:28

    Softwoods and Hardwoods

    Softwoods and hardwoods, derived from different types of trees, are distinguished by their leaf structures and cellular compositions, each serving unique purposes in construction and manufacturing. Softwoods come from cone-bearing trees with needle-like leaves and are predominantly composed of longitudinal cells called tracheids and a smaller proportion of radial cells known as rays. Due to their cellular structure, softwoods are commonly used in construction for structural frames, sheathing,...
    Wood Products01:21

    Wood Products

    Wood products encompass a broad range of materials crafted from wood strands, veneers, lumber, and even waste wood-like shreds, designed for both structural and nonstructural purposes. Various specialized wood products have been developed to enhance strength, durability, and versatility in building applications.
    Glue-laminated wood, often referred to as glulam, combines multiple smaller pieces of dimensional lumber using adhesives to form a single, larger piece. Cross-laminated timber consists...
    The Fossil Record02:56

    The Fossil Record

    The fossil record documents only a small fraction of all organisms that have ever inhabited Earth. Fossilization is a rare process, and most organisms never become fossils. Moreover, the fossil record only exhibits fossils that have been discovered. Nevertheless, sedimentary rock fossils of long-lived, abundant, hard-bodied organisms dominate the fossil record. These fossils offer valuable information, such as an organism's physical form, behavior, and age. Studying the fossil record helps...