bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geoscience Field Education: A Recent Resurgence
Authors: Whitmeyer Steven J. , Mogk David W. 
Published: November 2009

Field education traditionally has been an integral component of undergraduate geoscience curricula. Students have learned the fundamentals of field techniques during core geology courses and have honed their field credentials during class‐specific field trips, semester‐long field courses, and capstone summer field camps. In many geoscience departments, field camp remains a graduation requirement, and more than 100 field camps currently are offered by U.S. universities and colleges (see http://geology.com/field‐camp.shtml).During the past several decades, however, many geoscience departments have moved away from traditional geologic fieldwork and toward a broader theoretical and laboratory‐intensive focus that encompasses a range of subdisciplines. Trends that have influenced these shifts include (1) the decline in the late twentieth century of the petroleum and mining industries, which have consistently championed the values of fieldwork; (2) a decrease in the number of professional jobs that incorporate field mapping; (3) a decline in the number of geoscience majors nationwide [American Geological Institute (AGI), 2009]; and (4) barriers to fieldwork, including time requirements, cost, liability, and decreasing access to field sites.
Global Satellite Vegetation Monitoring: Long Term Global Monitoring of Vegetation Variables Using Moderate Resolution Satellites; Missoula, Montana, 16–19 June 2009
Authors: Nightingale Joanne , Running Steven 
Published: November 2009

The fourth global vegetation workshop illuminated critical issues related to the current status and future of satellite vegetation monitoring in the climate change and carbon‐trading era. About 120 scientists representing 12 countries attended the 3‐day workshop.Plenary talks were given by distinguished remote sensing/ecosystem scientists. John Townshend (University of Maryland) presented his views on the current challenges in global remote sensing. Richard Waring (Oregon State University) offered new ecological insights to improve predictions of terrestrial carbon balances from satellite data sets. Compton Tucker (NASA Goddard Space Flight Center) gave a synopsis of land observations, climate data gaps, and essential climate variables for global vegetation monitoring.
Environmental Responses to a Land Reclamation Project in South Korea
Authors: Son SeungHyun , Wang Menghua 
Published: November 2009

In 1991, South Korea embarked on an ambitious project to reclaim nearly 401 square kilometers of land and tidal flats from the Yellow Sea by building a system of two dikes extending 33 kilometers across the mouths of the Dongjin and Mangyeong rivers, offshore of the Saemangeum district (see Figures 1a and 1b). Called the Saemangeum Reclamation Project, the endeavor will allot about 283 square kilometers of the reclaimed land for crop production (mostly rice) through irrigation of the rivers' estuaries, which will be extended by about 23 kilometers when the bay fills up. The rest of the reclaimed land will be a water reservoir for agricultural use [Lie et al., 2008].The construction of the Saemangeum Reclamation Project's northern dike was completed in June 2003; the southern dike was finished in April 2006. Two gaps in the southern dike allow water exchange, and two gates control the water level inside the dikes. The reclamation project, the biggest such endeavor in South Korea, is expected to be completed around 2030.
Climate Change: The Need to Consider Human Forcings Besides Greenhouse Gases
Authors: Pielke Roger , Beven Keith , Brasseur Guy , Calvert Jack , Chahine Moustafa , Dickerson Russell R. , Entekhabi Dara , Foufoula‐Georgiou Efi , Gupta Hoshin , Gupta Vijay , Krajewski Witold , Krider E. Philip , Lau William K. M. , McDonnell Jeff , Rossow William , Schaake John , Smith James , Sorooshian Soroosh , Wood Eric 
Published: November 2009

Humans are recognized as having a major role in influencing environmental variability and change, including their influence on the climate system. To advance scientists' understanding of the role of humans within the climate system, there remains a need to resolve which of the following three hypotheses is correct:Hypothesis 1: Human influence on climate variability and change is of minimal importance, and natural causes dominate climate variations and changes on all time scales. In coming decades, the human influence will continue to be minimal.
Crop protection.
Authors: Csizinszky A. A. , Schuster D. J. , Jones J. B. , Lenteren J. C. van 
Published: November 2009

Abstract

This chapter covers control of weeds, nematodes, insect and mite pests (including those causing chewing damage to seedlings, foliage and fruits or sucking damage to fruits, foliage and flowers), and fungal, bacterial and viral plant pathogens. The first part of the chapter largely concerns crop protection in field-grown tomatoes. This is followed by discussion of the integrated management of pests in greenhouse tomatoes, where biological control measures can be used.
Apple rootstocks.
Authors: Webster A. D. , Wertheim S. J. 
Published: November 2009

Abstract

This chapter covers the species, cultivars and sub-clones of apples used as rootstocks, as well as the different methods of rootstock propagation; the effects of rootstock on the growth and adaptability to environmental conditions of scions; breeding of new apple rootstocks; apple rootstocks propagated from seeds; vegetatively propagated rootstock clones and sub-clones used to control tree vigour; clonal rootstocks used to adapt trees to unfavourable conditions such as plant pathogens and pests, freezing and drought; and use of interstocks and interstems.
Organic apple production - with emphasis on European experiences.
Authors: Weibel F. , Häseli A. 
Published: November 2009

Abstract

This chapter covers the basic principles and legal basis of organic farming, as well as the extent and importance of organic fruit production in Europe, and the supply situation and market outlook for such produce. Conditions favouring the conversion to organic apple production, as well as site requirements, planting systems, choice of rootstocks and cultivars, areas and features for ecological compensation, and nutrient, soil, pest and weed managements for such type of farming are discussed. Notes are presented on organically approved disease and pest control products.
The competitive (micro)environment: the destination and the tourism system.
Authors: Ritchie J. R. B. , Crouch G. I. 
Published: November 2009

Abstract

This chapter examines how the principal elements of the competitive micro-environment are structured in the context of a tourism destination. The basic elements of the microenvironment are the suppliers and supporting industries, tourism and hospitality enterprises, marketing intermediaries and facilitators, customers, and the destination marketing organization and other publics. The chapter concludes with an integration of the impacts of these elements in terms of their overall effect on the destination in question, the effect of competing destinations, and the tourism system as a whole.
Flowering.
Authors: Davenport T. L. , Stern R. A. 
Published: November 2009

Abstract

This chapter reviews the following aspects of shoot and flower development in longan and litchi (Litchi chinensis): types of shoots (vegetative shoots, generative shoots, and mixed and transition shoots); role of growth regulators (cytokinins, auxins, ethylene, gibberellins and abscisic acid) and potassium chlorate in shoot initiation; effects of environmental factors (temperature, drought, nitrogen, and pruning and girdling) on shoot induction; floral morphology; floral development; sex ratio; ovule development and pistil receptivity; pollen viability; and pollination.
Photosynthesis and productivity.
Authors: Menzel C. M. 
Published: November 2009

Abstract

This chapter on photosynthesis and productivity in litchi (Litchi chinensis) and longan covers the following: relationship between photosynthesis and plant development; effects of the environment on photosynthesis; assimilate production and distribution; relationship between fruit growth and leaf expansion; relationship between yield and assimilate supply; relationship between fruit size and yield; relationship between yield and tree size; effects of light and temperature on growth and productivity; effects of planting density and pruning on productivity; and practical aspects of pruning. Tabulated data on the productivity of litchi and longan in China and Thailand, and on the effects of leaf position and stage of development on leaf fresh weight and area, chlorophyll content, net carbon dioxide assimilation, and stomatal conductance in litchi (cv. Bengal) in Queensland, Australia, are presented.
Plant nutrition and fertilizing.
Authors: Menzel C. M. 
Published: November 2009

Abstract

This chapter on longan and litchi (Litchi chinensis) covers the following: effects of soil type, soil pH, salinity and mycorrhizas on fertilizer requirement; factors affecting leaf composition; leaf and soil analyses, and orchard surveys for fertilizer requirement determination; N, P, K, Ca, Mg, Zn, Fe, Cu, B and Mn nutrition (concentration and uptake, effects on productivity, and deficiency symptoms); fertilizer programme for young orchards in Australia; and fertigation.
Harvesting and storage.
Authors: Holcroft D. M. , Lin HeTong Lin HeTong , Ketsa S. 
Published: November 2009

Abstract

This chapter on longan and litchi (Litchi chinensis) describes the following: fruit morphology; fruit respiration and ethylene production; aril composition; pericarp structure and composition; postharvest disorders (pericarp browning, chilling injury and aril breakdown); fruit maturity indices; harvesting, grading and packing; postharvest treatments (sulfur fumigation of fruits, acid treatments for retaining litchi pericarp colour, temperature management, cold storage, reduction of water loss, controlled and modified atmospheres, and disinfestation); and transport and marketing. Harvesting and storage of longan and litchi fruits in Australia are largely covered.
Introduction to risk in agriculture.
Authors: Hardaker J. B. , Huirne R. B. M. , Anderson J. R. , Lien G. 
Published: November 2009

Abstract

This chapter first offers examples of risky decisions in agriculture and discusses their implications. The need to take account of risk in agriculture is then highlighted, and the concepts of risk and uncertainty are explained. The chapter also considers the individuals who need to think about risk in agriculture and then presents a general approach to risk management in agriculture as well as an overview of formal decision analysis.
History and current use of feed additives in the European Union: legislative and practical aspects.
Authors: Doeschate R. A. H. M. ten , Raine H. 
Published: November 2009

Abstract

Whilst the term feed additives encompasses a variety of products, this chapter will concentrate on product groups such as antibiotic growth promoters, coccidiostats and enzymes. These products have been, and are, subject to scrutiny and licensing at European Union (EU) and national level. The history of antibiotic growth promoters serves as a case study for the development of a product group, ensuing legislation, pressure group activity and the subsequent demise of the product group. EU legislation has evolved over the years from a situation of limited scope and relatively relaxed rules to the current system where the scope is being extended to more products and with stricter rules. The current EU regulation (1831/2003) is based on the precautionary principle related to human health, animal health and the environment. At present there are signs that legislation has tightened to such a level that certain products are not available on the EU market, maybe as a result of high costs or delays, due to the registration process. A balance needs to be found between effective legislation regulating the safe use of additives and allowing new product and concept development. From a practical nutritionist's point of view the whole area is very complicated, with several products on the market, and it is unclear whether they are additives in the legal sense or not, but there is a responsibility on the nutritionist to ensure compliance with the law. With antibiotic growth promoters disappearing, several 'replacement' products need to be evaluated, which is another big challenge for nutritionists.
Microbes of the chicken gastrointestinal tract.
Authors: Apajalahti J. , Kettunen A. 
Published: November 2009

Abstract

The gastrointestinal tract of an adult chicken is inhabited by up to 1013 bacteria. This microbiota has a wide metabolic potential and it affects both the nutrition and health of the host. The microbial populations in the chicken gut grow rapidly, the density plateauing within 3-4 days of hatching. The structural evolution, however, is likely to continue for the entire life of a broiler chicken. The effect of microbes on the commercial aspects of a poultry enterprise is apparent to the farmer only in extreme cases. Known pathogens, such as Clostridium perfringens and Escherichia coli, may reduce bird growth and liveability and human pathogens, such as Salmonella enterica, may lead to carcass condemnation and reduced income. Most of the time, however, the effect of bacteria is less obvious to the grower, and one or many of the unidentified bacterial species present may cause non-specific enteritis. The composition of the intestinal bacterial community has been studied by many researchers. The methods used here varied markedly and, therefore, it is often impossible to know whether the varying observations are due to geography, feeding regimen, bird management or to the methods used for microflora analysis. The microbial community of the caecum is far more diverse and less well characterized than that of the crop and small intestine. The abundance of bacteria is significantly affected by feed composition and ingredients. We have numerous means of modulating the microflora and these can be applied as soon as knowledge from well-designed studies unveils the correct bacterial targets.
Effect of non-starch polysaccharidases on avian gastrointestinal function.
Authors: Bedford M. R. 
Published: November 2009

Abstract

Non-starch polysaccharidases, which include cellulases and xylanases, are routinely used in poultry diets containing wheat, barley, oats, triticale and rye and, more recently, maize. The beneficial responses observed may be based on one or more of three proposed mechanisms of action, namely: (i) cereal endosperm cell wall hydrolysis; (ii) reduction in intestinal viscosity; and (iii) provision of fermentable oligomeric substrates as a result of cell wall hydrolysis. Since each mechanism elicits a specific series of responses at the intestinal level, and the extent of involvement of each will vary depending upon circumstances, there are a variety of potential responses observed. Changes in intestinal function may be driven by changes in nutrient supply and/or changes in the physico-chemical conditions (the viscosity of the intestinal contents, the nutrient-binding ability of the fibre fraction and the thickness of the unstirred water layer) of the intestine. Nutrient supply encompasses not only improved nutrient extraction by the host, and thus reduced availability for the intestinal flora, but also the provision of oligomeric substrates through cell wall hydrolysis. As a result of such changes there may be subsequent, interrelated changes in the structure and size of the intestinal tract, in pancreatic enzyme secretion, in the quantity and chemistry of mucin secreted and in the quantity and species distribution of resident intestinal flora. The qualitative and quantitative changes in intestinal function observed are very much dependent upon the status in the absence of enzyme, which highlights the fact that responses upon use of enzymes are variable, being greatest in poor-quality diets.
Competitive exclusion in poultry production.
Authors: Schneitz C. 
Published: November 2009

Abstract

The concept of Competitive Exclusion or CE, sometimes also described as the 'Nurmi concept', involves treatment of newly hatched chickens with mixed bacterial preparations originating from the gut of healthy adult birds to control intestinal disturbances. The treatment has also been given successfully to older birds after therapeutic doses of antibiotics to regenerate the intestinal microflora. CE treatment is usually applied by spraying, but can also be given via the first drinking water. The concept of CE was originally developed to control Salmonella in growing chickens but has, with time, been expanded to involve several other enteropathogens like chicken and human pathogenic Escherichia coli, Clostridium perfringens, Listeria and Campylobacter. The chicken intestinal flora has also been shown to be efficacious in other avian species like turkey, quail and pheasant. The mechanisms by which the intestinal bacteria inhibit the invasion and proliferation of enteropathogens include competition for receptor sites, elaboration of inhibitory compounds and competition for nutrients or stimulation of the immune system. In addition to pathogen control, it has been shown in field studies that CE treatment enhances the growth and decreases the mortality of birds and improves the feed conversion. The nutritional effects of the treatment have been confirmed in well-controlled laboratory studies. Increased bacterial resistance to antibiotics in humans has caused an increase in public and official interest in abandonment of the use of growth-promoting antibiotics. Competitive exclusion is a reliable alternative because the treatment is fully biological, it does not leave any residues and only one treatment on the day of hatch is normally enough.
The genetics of modern commercial poultry.
Authors: McKay J. C. 
Published: November 2009

Abstract

Genetically improved strains of poultry have been a major contribution to the success of the poultry industry, which is a major source of animal protein for the human population in most countries of the world. Improvements in health, nutrition and environmental management have also contributed to improved performance, but the majority of the change has been attributed to genetic improvement. Egg production has been improved consistently since the late 1930s, and the industry continues to improve the efficiency of laying hen production by at least 1% per year. This requires the simultaneous improvement of multiple traits, including egg number, egg size, liveability, persistency and mature body weight. There is also continuing progress in uniformity of egg size and colour and freedom from defects. In broilers, combined selection for growth, body composition, feed efficiency and liveability continues to deliver 2-3% improvement per year in the efficiency of meat production. Other traits such as robustness, specific and general disease resistance, and absence of metabolic defects have also contributed to this progress.
Incubation and hatching.
Authors: French N. A. 
Published: November 2009

Abstract

The emphasis of poultry incubation research since the late 1980s has focused on four different themes, namely: (i) the relationship between incubation temperature and embryo temperature; (ii) how to engineer commercial incubators to meet the requirements of the embryo; (iii) the effect of genetic changes to poultry breeds on their incubation requirements; and (iv) the effect of incubation environment on the post-hatch performance or epigenetic adaptation. It is the intention of this short review to focus on these four areas of research and to discuss how they are affecting commercial practice. A simple systems model is used to describe how embryo growth and metabolism, the properties of the egg in which the embryo develops and the environment of the incubator interact to determine the embryo temperature. The model shows that the relationship between the egg and its incubation environment is a dynamic process, with the embryo responding to its incubation environment but also affecting the environment. Our understanding of these interrelationships has resulted in better design of artificial incubators and the development of methods to directly measure the response of the egg to its environment. The third section of the review discusses whether the genetic improvements to poultry in both egg and meat production have altered the incubation environment of the embryo. It is concluded that there are differences in embryo metabolic rate between genetic lines, which may impact on the optimum incubation environment. It was also noted that the mechanism by which genetic selection had affected embryo metabolism was not yet understood. The last section of the chapter discusses the possibility that post-hatch performance can be affected by the incubation environment and presents evidence to show that this may indeed be the case.
Photoperiod and control of breeding.
Authors: Lewis P. D. 
Published: November 2009

Abstract

Photoperiod is the most important environmental manipulator of sexual development and reproductive activity, and changes in photoperiod exert far greater effects on sexual maturation than constant photoperiods. The critical daylength to initiate sexual maturation appears to be common for all species of poultry at between 10 and 11 h, with a saturation daylength of between 13 and 14 h. The photoperiodic response varies with the type of poultry and is principally dependent on whether or not the bird exhibits photorefractoriness and if so in which form. Photorefractoriness is a condition that, in its extreme, prevents gonadal maturation in the year of hatch and limits breeding to spring and early summer. Birds are hatched photorefractory and need a period of short days to dissipate the condition, the time requirement for which varies with photoperiod and the degree of feed restriction. Reproductivity is subsequently ended by the onset of adult photorefractoriness. Geese and game birds exhibit absolute photorefractoriness and have a breeding season limited to about 4 months. Their sexual maturity is indefinitely delayed when reared on long days. Turkeys, and probably Muscovy ducks, exhibit relative photorefractoriness, become sexually mature in their first year and suffer no more than a 3- to 4-week delay in maturity when not reared on short days (below critical daylength). Turkeys do not normally have their feed intake restricted and so require only about 2 months of short days to become photosensitive. Broiler breeders also exhibit relative photorefractoriness, but because their feed intake during rearing is severely restricted, they need 4-5 months of short days to become photosensitive. Meat-type ducks do not exhibit photorefractoriness and rearing on short photoperiods is not essential.