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Medium 9781780646862

4: Plants and Water

Finley, S. CABI PDF

4

Plants and Water

Water availability is a principal limiting factor to plant development and crop yield. In laboratory studies, the total dry matter production of crop plants has been shown to have a linear relationship to water uptake: the more water used, the more yield produced, up to the point where the full plant water requirement is met.1

Water plays several roles in plant development and crop production:

1. Water is the principal transport mechanism for moving essential nutrients, minerals and dissolved carbohydrates through plant tissues. Water moves from regions of low to high potential, pulling it from the soil into roots, upward through plant tissues, and out through the leaf surface into the atmosphere in a continuous sequence driven by transpiration. As it moves through the plant, water delivers essential elements from roots to shoots and leaves where they are used in plant metabolic processes.

2. Water is a critical reactant in chemical reactions occurring in plant cells.

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6: Soil-focused Strategies: Reducing Water Loss

Finley, S. CABI PDF

6

Soil-focused Strategies:

Reducing Water Loss

Chapter 2 introduced the concepts of productive and unproductive water uses within the overall farm water budget. Recall that the only fully productive use of water is crop transpiration (T), which is supplied by readily available soil water stored within the root zone. Typically, the percentage of rainfall that ultimately translates into transpiration is very low, in most cases between 15% and 30%.1 Unproductive water uses, including e­ vaporation, runoff, weed growth and deep percolation result in the loss of the remaining portion of the water budget. Loss percentages vary widely by context – in extreme cases, the combined forces of evaporation, runoff and deep percolation can consume more than 90% of the rainwater falling on the field.2

In order to improve rainwater productivity, farm management practices must seek to shift the way that water inputs from rain are partitioned among these competing uses. The goal is to promote infiltration and reduce water losses as much as possible, leaving more water available for use in crop transpiration.

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3: Soil and Water

Finley, S. CABI PDF

3

Soil and Water

More than anything else, the key to enhancing resilience and promoting water availability for crop growth lies in the proper care of farm soils. In fertile regions, the native soil underlying forests, brush or grasslands tends to be naturally ‘healthy’, that is, rich in nutrients with good structure and organic matter content. When land is cleared for farming, soil can quickly lose its ‘healthy’ qualities, especially if farming practices employed do not encourage its regeneration. Without proper management, agricultural soils can become completely depleted in as little as a few decades or even a few years after clearing, depending on the nature of the land and its use.1

Some negative effects that agriculture can have on the soil include:

nutrient mining (continual removal of nutrients without renewal); breakdown of organic matter; loss of water holding capacity; compaction; erosion; surface sealing (crusting); and deterioration of natural habitat for soil organisms (microorganisms, insects, and worms).

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Medium 9781623491376

1. The Unique Characteristics of Water and Water Rights in Texas

Porter, Charles R. Texas A&M University Press ePub

THE UNIQUE CHARACTERISTICS OF WATER AND WATER RIGHTS IN TEXAS

Determining a water right in Texas depends on which of three geological containers holds the water.1 The first container is surface water, or water that flows on the surface of the ground in a watercourse.2 The State of Texas owns the water in a watercourse. The assessment of what makes up a watercourse can be complicated, so the safest way to look at ownership of surface water is to consider all water flowing in any stream or area with bed and banks to be surface water. Surface water is not yours to own but, except in unique situations, is owned by the State of Texas. Knowing this may save you many dollars in fines and hours of angst. If you have a question about surface water ownership on real property you own or are considering purchasing, ask the Texas Commission on Environmental Quality (TCEQ) for a determination.

The second geological container is known as diffused surface water, or rainwater that runs off your roof or over the surface of your land without flowing in a stream or channel. The water in this container is owned by the landowner.

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Medium 9781786391445

17 Implication of Nanotechnology for the Treatment of Water and Air Pollution

Singh, H.B.; Mishra, S.; Fraceto, L.F. CABI PDF

17

Implication of Nanotechnology for the Treatment of Water and Air Pollution

R.K. Chaturvedi*

Center for Integrative Conservation, Xishuangbanna Tropical Botanical

Garden, Chinese Academy of Sciences, Yunnan, China

17.1 Introduction

Due to the revolution in the development of science and technology at the nanoscale, there has been an increase in the ability to fabricate and manipulate the nanosized materials; by which we mean particles smaller than 100 nm. Interest in these nanomaterials has increased tremendously because they produce many opportunities to improve the performance of material. Metal-based nanoparticles, consisting of Cu, Au, Ag, etc., have been generally used as industrial electrode, magnetic materials, chemicals, catalysts and optical media. In agriculture, the use of nanoparticles has just started, but is increasing its dimensions. With the help of nanosciences, plant growth has been enhanced by using a wide range of applications of nanotechnology (Nair et al., 2010).

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Medium 9781780646862

2: Goals of Agricultural Water Management

Finley, S. CABI PDF

2

Goals of Agricultural Water

Management

Water is a vital component of every agricultural project. In addition to supporting plant growth, water is critical to maintaining soil health and promoting the overall ecological well-being of the land, which are essential in ensuring the long-term viability of the farm. In this book, the term soil and water management practices is used to designate the range of farming practices that influence the way in which water flows through the farm environment and is transformed into crop yields. This category includes methods of water application, but also cropping systems, soil management practices, and land use patterns. The purpose of this publication is to define and explain sound practices for managing water in the cultivation of field crops. While the management of soil and water resources is equally important in other agricultural categories such as livestock rearing, aquaculture and forestry, these remain outside of the scope of this book.

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12: Water Sources for Agriculture

Finley, S. CABI PDF

12

Water Sources for Agriculture

Especially in dryland environments, the fundamental prerequisite for irrigation

­development is a good and reliable source of water. When assessing a water source for use in agriculture, it is relevant to consider both the quantity and quality that will be accessible over time. If one of these factors proves to be insufficient, the harm caused by an irrigation project could outweigh its benefit in the long term.

This chapter addresses the character and quality of water sources commonly used to supply irrigation projects. It also introduces some water contaminants of special concern, and provides a brief overview of water-lifting devices traditionally employed on small farms.

Water Quantity

The quantity of water readily available from a blue water source is difficult to assess with accuracy, since water levels, stream size and groundwater flows fluctuate significantly over time. Climate, rainfall, and the activities of upstream users all have a strong influence on the quantity of water that will be accessible from a blue water source at a given point in time.

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8: Crop-focused Strategies: Using Available Water Wisely

Finley, S. CABI PDF

8

Crop-focused Strategies: Using

Available Water Wisely

The plant also has a role to play in water productivity. Crop management techniques can enhance the plant’s ability to use soil water efficiently, further reinforcing the benefit of the soil and water management practices described in

Chapters 6 and 7. Cropping systems can also be designed to encourage drought resistance and mitigate the harmful effects of dry periods. Drought resistance ultimately improves water productivity because it increases the potential for producing crop yields in seasons disrupted by dry spells.

Cropping patterns have a considerable impact on water productivity. Crop layouts and plant combinations can be calibrated to produce a maximum amount of product (or income) from within available water supplies. Often, this involves rotating between different plant varieties with complementary water and nutrient requirements.

Drought resistance can also be enhanced by selecting drought-resistant cultivars, and by training the physiological adaptation mechanisms of existing crops to access scarce soil water or improve the efficiency of the conversion process that transforms it into product.

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Medium 9781574412710

Water

Tim Johnston University of North Texas Press PDF

Water

She was a good sleeper, a dependable sleeper, but that night

Charlotte woke up with her heart whumping, like a young mother.

There had been something.

She lay in the dark, not breathing. At one window the drapes were shaped by faint light from the street, but at the other there was nothing, no light from the neighbors, no moonlight, and the effect was briefly frightening, as if the wall had fallen away into space, or a black sea.

She drew the alarm clock into focus: 1:36. She had a son who would stay out late, but when he came home he was like a cat, and if she heard him at all it was because she had gotten up to use the washroom, pausing by his door just long enough to hear him clicking at the computer in there, or humming to the iPod, or shhshing Ginny Simms, his girl.

She heard none of this now, nothing at all but the heat pumping invisibly, bloodlike, in the walls of the house. This was late

October, two nights before Halloween, the first truly cold night of the season.

She closed her eyes and the dream she’d been having eddied back to center—a dream of hands, the feel of them, the smell of them; muscle and tendon, palm and finger. Her body, under the bedding, still hummed. She breathed, she slowed, she drifted down.

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Medium 9781626568976

4 Locate the Bait: What we gain when conversations lose

Jay, Jason Berrett-Koehler Publishers ePub

We’ll begin this chapter with another story from Jason:

When I came to MIT in 2005 to pursue a PhD, I joined a group of graduate student advocates. We put together a little manifesto about “what MIT should do” on sustainability, collected dozens of signatures from faculty, and handed them off to the administration. We asked for a meeting with the president of MIT so we could present our demands in person. We felt pretty cool.

When we heard back from the president’s office, however, we were told that they didn’t know what to do with our proposal: we had no clear “asks,” and they didn’t know how to interpret what we were requesting.

To be honest, we didn’t know either, but it was easier to stew in frustration and demonize the administration. We decided that “they” didn’t get it, weren’t taking us seriously, and didn’t really want to do what “they” should do.

After the failed petition, our next approach was to push for an event with more focus: one in which we could force the administration to publicly commit to “walking the talk” and making the campus more energy efficient.

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Medium 9780253354839

11. Fucking close to water: Queering the Production of the Nation

Catriona Mortimer-Sandilands Indiana University Press ePub

BRUCE ERICKSON

Although I have been for the last twenty years, credited with the quote you use, “A Canadian is someone who knows how to make love in a canoe,” it is not actually my own—at least I don’t think so.

—Pierre Berton

And somewhere in that self-consciousness, which knows it is fundamentally incompatible with itself, the nation acknowledges that its strategies of self-consciousness are inadequate to their task, and it silently confesses that its existence is also a crime.

—Chris Bracken

In order to start with honesty, I should inform the reader that my title, and my subject, is an absolute cliché for a novel take on the canoe in Canada. One of the first collections on canoeing in Canada (Raffan and Horwood 1988) contained two articles that started with the proposition, credited to Pierre Berton, that, “a Canadian is one who can make love in a canoe” (Raffan 1999b, 255). Bruce Hodgins (1988), in his contribution to the anthology, reaffirms Berton’s statement by saying that “making love in a canoe is the most Canadian act that two people can do” (45). Philip Chester adds a qualifier, stating, “while this may or may not be true, I would add that, unlike his American cousin, the true Canadian knows enough to take out the centre thwart” (1988, 93). The list of authors who use this quotable quote as an introduction to canoeing in Canada is enough to leave the phrase behind (Benidickson 1997, Chester 1988, Hodgins 1988, Raffan 1999a, Raffan 1999b) and the “bad joke” twist that I have added is less than heroic, taken from a Monty Python sketch as it is. However, there is, I believe, more to this—something highlighted by my use of a joke in the title, somewhat along the lines of flogging a dead horse—a talent for making jokes useful even after they have failed. Indeed, my suggestion is that it is failure itself that is captured so effectively by the statement attributed to Pierre Berton.

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Medium 9781780644479

4: Water-soluble Biodegradable Polymers for Drug Delivery

Kharkwal, H.; Janaswamy, S. CABI PDF

4 

Water-soluble Biodegradable Polymers for Drug Delivery

Bhanu Malhotra1, Harsha Kharkwal2,* and Anuradha Srivastava3

Amity Institute of Biotechnology and Amity Center for Carbohydrate Research,

Amity University, Noida, India; 2Amity Center for Carbohydrate Research and

Amity Institute of Phytomedicine and Phytochemistry, Amity University Uttar

­Pradesh, Noida, India; 3Biological Sciences and Geology, Queensborough

Community College, Bayside, New York, USA

1

Abstract

At the heart of polymer chemistry and biomedical applications lie water-soluble polymer drug conjugates for novel drug delivery systems. Designing multifunctional water-soluble polymer drug conjugates via copolymerization of bioactive compounds, and incorporating hydrophilic groups, makes them extremely water soluble and with improved biocompatibilities. Hydrophobic charged groups can be introduced into the polymers, which enable them to carry out specialized interactions and responses. Water-soluble polymer drug conjugates have the ability to store prodrugs (inactive drugs), facilitating the transfer of drugs passively or actively to the target site then activating them through cellular signalling cascades and bringing about the desired response. This chapter throws light on the advances made in natural and synthetic water-soluble polymer drug conjugates for various different biomedical applications.

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Medium 9781626569737

5 The Amazing and Scary Rise of Artificial Intelligence

Wadhwa, Vivek; Salkever, Alex Berrett-Koehler Publishers ePub

Many of us with iPhones talk to Siri, the iPhone’s artificially intelligent assistant. Siri can answer many basic questions asked verbally in plain English. She (or, optionally, he) can, for example, tell you today’s date; when the next San Francisco Giant’s baseball game will take place; and where the nearest pizza restaurant is located. But, though Siri appears clever, she has obvious weaknesses. Unless you tell her the name of your mother or indicate the relationship specifically in Apple’s contact app, Siri will have no idea who your mother is, and so can’t respond to your request to call your mother. That’s hardly intelligent for someone who reads, and could potentially comprehend, every e-mail I send, every phone call I make, and every text I send. Siri also cannot tell you the best route to take in order to arrive home faster and avoid traffic.

That’s OK. Siri is undeniably useful despite her limitations. No longer do I need to tap into a keyboard to find the nearest service station or to recall what date Mother’s Day falls on. And Siri can remember all the pizza restaurants in Oakland, recall the winning and losing pitcher in any of last night’s baseball games, and tell me when the next episode of my favorite TV show will air.

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Medium 9781603442015

Texas Water Politics Forty Years of Going with the Flow

Ken W Kramer Texas A&M University Press ePub

Ken Kramer

EVEN after forty years I can still visualize it. The “it” is the cover of the first issue of the biweekly Texas Observer I had ever seen. The year was 1969, and I had just embarked on my first graduate school experience—starting work on a master’s degree in political science at Stephen F. Austin State University in Nacogdoches in East Texas. The professor in one of my classes had offered his students the opportunity to participate in a class subscription to the Observer, a liberal journal of opinion that provided exceptional coverage of Texas politics and government (and still does). Although I was a Republican at the time, I was extremely interested in politics, and, political philosophy aside, the Observer was touted as a good source of information about the state’s political comings and goings; so I signed up to receive one of the copies twice a month.

As it turns out, that was a momentous decision in my life—although not perhaps recognizable as such at the time. The first issue of the Observer I saw was devoted in its entirety to something called the “Texas Water Plan”—about which I knew nothing although I was already interested in environmental issues. The cover, which struck me so profoundly, showed a cartoon of several leading state officials, including then former governor John Connally and then governor Preston Smith, waterskiing or otherwise frolicking in or around some body of water. These folks were promoting this thing called the Texas Water Plan.

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Medium 9781609949891

1. The Movements of Water

Capra, Fritjof Berrett-Koehler Publishers ePub

Among the four classical elements, water held by far the greatest fascination for Leonardo. Throughout his life, he studied its movements and flows, drew and analyzed its waves and vortices, and speculated about its role as the fundamental “vehicle of nature” (vetturale della natura) in the macrocosm of the living Earth and the microcosm of the human body.1

Leonardo’s notes and drawings about his observations and ideas on the movement of water fill several hundred pages in his Notebooks. They include elaborate conceptual schemes and portions of treatises in the Codex Leicester and in Manuscripts F and H, as well as countless drawings and notes scattered throughout the Codex Atlanticus, the Codex Arundel, the Windsor Collection, the Codices Madrid, and Manuscripts A, E, G, I, K, and L.2 The sheer bulk of Leonardo’s writings on water duly impressed his contemporaries and succeeding generations of historians. In fact, water was the only subject, apart from painting, of which an extensive compilation of handwritten transcriptions from the Notebooks was made. This collection of notes, transcribed in the seventeenth century and comprising 230 folios, was published in 1828 in Bologna under the title Della natura, peso, e moto dell’acque (On the Nature, Weight, and Movement of Water).3

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