What is Soil Moisture Measurement and Control?

Before we talk about specifics, let us take a step back and look at the living system in which we will be working.

The Soil, Water, Plant System

Evapotranspiration moves water out of the system and rain or irrigation replaces it. The soil provides storage for the water. Typically, the plant removes water according to the chart below.

Water is pulled by the roots into the plant. The soil is attracting the water as well. This competition between the plant and soil for the water creates tension. As the water is depleted by the plant, it first takes the water that is most easily released and continues to take water that is more and more tightly held by the soil. This tension can be measured by soil moisture measurement instruments. The higher the tension created, the harder it is for the plant to extract water from the soil. Eventually there will be no more “available water” for the plant. Most landscape plants suffer from just the opposite, no oxygen in the soil because of too much water.

Why is fluid care important?

High-performance servohydraulic systems require very clean oil to maximize performance and extend the life of system components.

While less sophisticated hydraulic systems may function acceptably with lower levels of oil cleanliness, high-performance servohydraulic equipment will “silt up” and perform erratically when subjected to particulate levels that are greater than an ISO 4406 rating of 16/13/9. Servovalves must operate smoothly and predictably to deliver the tightly regulated pressures and fluid flow for which they are designed.

How can hydraulic system life be maximized?

Regular monitoring and maintenance of the hydraulic fluid promotes the maximum operating performance and service life of the servohydraulic system and its components. Two specific items must be checked regularly—contaminants in the fluid and the fluid’s chemical makeup.

Gone are the days of the intrepid globetrotting photographer armed with a manual FM10 around the neck and a hipsack full of film. At the most, her power requirements amounted to a pack of AA lithiums. Today’s professional travel and outdoor photographer is more likely to be found with a couple power-hungry digital SLRs bristling with fast-recycling smart flashes. She might even be toting a portable hard drive, a laptop and location light kit. Still, she finds herself in the same remote areas for extended periods of time as before. That means she needs portable power, and a sack of AAs aren’t going to cut it anymore. This document will explore the current technology of portable power for the modern outdoor and travel photographer.

Power Primer

This chapter provides an overview of the AR System API and explains when to use API programming.

This chapter discusses the following topics:

• API Overview on page 18
• AR System C and Java API Architecture on page 21
• AR System Plug-In API Architecture on page 22
• C API Call Components on page 23
• When to Use API Programming on page 23

API Overview

The API suite is composed of a C application program interface (API), a Java API, a plug-in API, and three APIs that use plug-ins.

This guide describes the C APIs and plug-in APIs. This introduction briefly discusses all APIs.

For more information on the Java API or the Java file names and locations, refer to the Java API documentation HTML files in the ardoc51.jar file in the \ArServer\api\lib folder (Windows) or the /ARServer/api/doc folder (UNIX). To access the Java API documentation, unzip the ardoc51.jar file, then click the index.html file.

The hardness of each gemstone below is based on a gem-trade standard called the Mohs scale. The higher the Mohs scale number, the harder the stone is. The highest Mohs scale rating is 10, diamonds. Anything with a Mohs scale rating of less than 7 is easily scratched.

Mohs’ scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer. It was created, in 1812, by the German mineralogist Friedrich Mohs and is one of several definitions of hardness in materials science.

Alexandrite
Alexandrite is the birthstone for June (along with the Pearl) and the anniversary gem for the 55th year of marriage. It changes from green to red, mauve or brown in incandescent light. Alexandrite has a hardness rating of 8.5. There are many synthetic alexandrites on the market. Natural alexandrite is very rare. Alexandrite is found in Brazil, Madagascar, Myanmar, Russia, Sri Lanka and Zimbabwe.

Glacier’s Wild Backcountry

Glacier represents the core of a vast tract of wildlands often referred to as the “Crown of the Continent.” More than 95% of Glacier’s 1,013,000-plus acres is proposed for inclusion in the national Wilderness Preservation System. It is the policy of the National Park Service to manage proposed wilderness areas in accordance with the Wilderness Act of 1964 in order to protect wilderness values and characteristics until such time as Congress acts.

The fundamental tenets of the Wilderness Act most visible to backcountry visitors include:

• Prohibition of motorized equipment and mechanized transport, including bicycles and canoe carts, in the backcountry (except during emergencies or to meet the minimum requirements for the administration of the area).
• Retention of the land’s primeval character and influence without permanent improvements (except for those authorized NPS administrative facilities essential to meet minimum requirements
  for the administration of the area and its historic structures).