Nearly all the vegetation biomes identified in the global map at the top of page 3-1 are found in North and Central America, as evident in the next illustrative map:

Some of these biomes are predominately composed of evergreens. There are two types of evergreens: Evergreen Needle Leaf (pine, spruce, fir, etc.) and Evergreen Broadleaf (laurel, magnolia, etc.). The pines are usually coniferous (cone-bearing) and in North America are widespread. Pine habitats fall into three main groups: Boreal Forests (mainly in Canada); Mountain Forests (further to the south); and Southern Forests (southeastern U.S.). Although examples from all three are included on this page, the concentration will be on Boreal Forests. In Asia, mainly Siberia, these are also called Taiga. These are the second most widespread plant biome type in the world, as indicated in the next map.

In western Canada's Boreal Forest the most common type of tree is the Lodgepole Pine. Its distribution is vast and many forests are almost continuous stands of these trees (next figure). They are a main source of lumber (as are the other pines mentioned above) and a very valuable commodity. Threats to their normal existence, such as fires and disease, can have a huge economic impact. On this page, we shall dwell upon just one specific and serious problem - the infestation of the Mountain Pine Beetle (MPB) - as a case study showing how remote sensing is helping.

Various species and genera of beetles are known to attack pines and other evergreens. Among common ones known by their non-taxonomic names are the Southern Pine Beetle, the Douglas Fir Beetle, the Spruce Beetle, the Turpentine Beetle, annd the Pinion Ips. Here are five different species in two genera.

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A Gallery of Photos from Space

We now present a gallery of exemplar photos, taken from representative Shuttle and other space missions. Some computer screens pair these images side-by-side but, small screens may display one above the other. Each one has a brief description.

Let's start with a sequence showing active and recent volcanoes on three continents. In the first pair, on the top is a vertical photo taken during STS-59 that shows a snow-covered island in Russia's Kamchatka Peninsula (far east Siberia) that has a volcanic caldera at each end, both with a central stratocone. Below it is an oblique scene that traces a long plume emanating from the Kliuchevskoi volcano in that peninsula during an active eruption.

Mount Saint Helens, in southern Washington State, erupted catastrophically in 1980. Astronauts photographed it in 1994, with a Nikon 300 mm lens, during the STS-64 mission, clearly showing the persistent aprons of ash deposits, despite considerable reforestation, lobes of lahars (ash-mud flows), and the great gap where part of the mountain was blown away.

It is interesting to place Mt. St. Helens in context with two other great stratovolcanoes in the Cascade Mountains of the western U.S. These two Shuttle views, one an oblique, false-color IR picture (looking northwest) and the second, a near vertical, natural-color shot, show Mount Saint Helens (MSH) to the west and Mounts Rainier and Adams to the east, all snow-capped. Indeed, MSH is the only volcano that is significantly offset from the main line of the Cascadian volcanic activity. Note the clear-cutting patterns in the forested countryside.

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A General Overview of the Cosmos - Introduction

Introduction

Before beginning this Section, we urge you to read through a page called the Preface (once there, hit your BACK button on the browser you use to return to this page). The Preface contains four major topics: 1) the role of remote sensing in astronomy; 2) some suitable references for additional information; and basic principles of 3) Relativity, and 4) Quantum Physics. The Preface contains a list of some very readable books and a number of Internet links to reviews or tutorials on Astronomy/Cosmology. Also, most of the illustrations in this Section were made from images and data acquired by spaceborne Observatories. A brief description of those Observatories is given on this Wikipedia website. Most of the ground-based Observatories are listed in this Caltech site.

As we did in Section 19, we begin with this statement: Astronomy and Cosmology depend almost entirely on remote sensing technology (mainly telescopes with various sensors) to gather the data and mold these into information about every thing in space beyond our Solar System.

Cosmologists - those who study the origin, structure, composition, space-time relations, and evolution of the astronomical Universe (and the possibility of a Cosmos as defined above) - generally agree that the Universe had a finite beginning and that it is expanding at a steady rate so that any two points (e.g., galaxies) move away from each other at speeds proportional to their separation. (The expansion of space has been referred to as the Hubble Flow, to honor Edwin Hubble who first verified the expansion). This beginning is commonly referred to as the Big Bang, which is not an explosion in the sense of, say, the detonation of dynamite but is an "explosion" of space itself as a continuing expansion accompanied at the outset by the creation and release of all energy and matter now occupying the ever growing Universe. (The Big Bang received its descriptive name as a disparaging comment from the astronomer Fred Hoyle, who advocated instead an infinitely large Universe of constant matter density [requiring continuous creation of new particles to maintain the density even as the Universe expanded within its infinite limits] as described in his [now rejected] Steady State model [developed in consort with Hermann Bondi and Thomas Gold]. This model also infers its Universe to have always existed [no creation event] and will exist largely unchanged [except for its expansion] forever; variants of this and other models have been put forth, as described on page 20-9).

As of 1990 the time of the Big Bang had been placed between 12 and 16 Ga ago (Ga = 1 billion years [b.y.]) ; the current best estimate (derived from observations made by the Hubble telescope and WMAP [a cosmic background radiation satellite]) lies close to 14 Ga (13.7 Ga is now recognized as the most accurate value [see page 20-9]). This is derived by measuring the time needed for light to have traveled from the observable outer limit of the Universe to Earth in terms of light years *, which can be converted to distances. In a sense, the term "light year" has a dual meaning. Thus, when the value of 2000 light years is stated for a star or galaxy, one could think in terms of distance: the entity is 2 x 103 x (3600 x 24 x 365.4 [the number of seconds in a year] x 2.998.... x 108 m/sec (see first footnote *), approximately 11.8 quintillion kilometers, away from the Earth as the observing platform. Or, one might think in terms of age: relativistically, we see the entity as it was 2000 years ago when the light first left it; cosmically we always look back in time when observing stars and galaxies. Both distance and age are valid connotations.

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A GIS Approach to Preserving a Rare Flower Habitat in Block Island, Rhode Island

This page will try to reconstruct an innovative application of GIS to a very specific topic. The work reported on was part of a Senior-Honors thesis done by Matthew A. Vadeboncoeur at Brown University who graduated with a Sc.B in Environmental Science in 2003 . His thesis title is Using GIS to prioritize Land for Management in the Conservation of a Rare Species: A Landscape-based Metapopulation Method for Northern Blazing Star on Block Island, RI. His goal was to identify areas on the island of optimal suitability for preservation of the wildflower as an aid to decision making by the citizenry and the Nature Conservancy regarding future land development.

Liatris scariosa var. novae-angliae is a beautiful wildflower whose English name is Northern Blazing Star found over much of New England but which is disappearing from Rhode Island. Block Island, RI is still a favored habitat. Two views of this lovely flower are seen below:

The flower favors grasslands and meadows, and at times near swampy growth. Here is a typical habitat on Block Island and a picture showing its occurrence in grassweed growth.

The entire state of Rhode Island is shown in this Landsat image. Block Island lies within Long Island Sound about 20 km (12 miles) south of Naragansett Bay.

An aerial oblique photo shows the entire island. Beneath that is a map of the island, which is about 11 km (7 miles) long

Block Island is a smaller version of Martha's Vineyard in Massachusetts in that it has permanent residents, residents in summer homes, and many tourists. This view shows much of the island (in winter) including the Great Salt Pond with most homes near shore but some inland.

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Data Structure of MapInfo - MapInfo

Data MI Pro dikelola dan disimpan dalam bentuk tabel. Setiap tabel menggambarkan satu jenis data, misalnya data kepadatan penduduk, distribusi customer, kemiringan lereng, penggunaan lahan dll. Secara logika, data MI Pro terdiri dari 2 bagian, yaitu data grafis yang menyimpan objek gambar (area, garis, titik, label dll.) dan data tabular atau atribut (database yang menyimpan nilai dari data grafis tersebut). Namun secara fisik, setiap tabel MI Pro biasanya terdiri dari 4 atau 5 file. Misalnya kita membuat tabel dengan nama Customer, maka MI Pro akan membuat file sebagai berikut.

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