Download or read book Estimating a Mass Nutrient Balance written by Stuart Dumay Klausner and published by . This book was released on 1997 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Improving Potassium Recommendations for Agricultural Crops written by T. Scott Murrell and published by Springer. This book was released on 2022 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book highlights concepts discussed at two international conferences that brought together world-renowned scientists to advance the science of potassium (K) recommendations for crops. There was general agreement that the potassium recommendations currently in general use are oversimplified, outdated, and jeopardize soil, plant, and human health. Accordingly, this book puts forward a significantly expanded K cycle that more accurately depicts K inputs, losses and transformations in soils. This new cycle serves as both the conceptual basis for the scientific discussions in this book and a framework upon which to build future improvements. Previously used approaches are critically reviewed and assessed, not only for their relevance to future enhancements, but also for their use as metrics of sustainability. An initial effort is made to link K nutrition in crops and K nutrition in humans. The book offers an invaluable asset for graduate students, educators, industry scientists, data scientists, and advanced agronomists.
Download or read book Nutrient criteria technical guidance manual lakes and reservoirs written by and published by DIANE Publishing. This book was released on with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessment of Soil Nutrient Balance written by Rabindra N. Roy and published by Food & Agriculture Org.. This book was released on 2003 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nutrient-balance assessments are valuable tools for delineating the consequences of farming on soil fertility. Various approaches and methods for different situations have been used in the past. This bulletin presents a state-of-the-art review of nutrient balance studies. It brings out the evolution of the approaches and methods, provides for comparisons among them, features the improvements made, and highlights remaining issues. This analysis will be useful in further development of the assessment methodologies as reliable tools for devising time-scale soil fertility management interventions.
Download or read book Protocol for Developing Nutrient TMDLs written by and published by . This book was released on 1999 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Agricultural Resources and Environmental Indicators 1996 97 written by Margot Anderson and published by DIANE Publishing. This book was released on 1998-05 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: Takes stock of how natural resources (land & water) & commercial inputs (energy, nutrients, pesticides, & machinery) are used in the agricultural sector; shows how they contribute to environmental quality; & links use & quality to technological change, production management practices, & farm programs. Provides a comprehensive source of data & analysis on the factors that affect resource use & quality in American agriculture. Examines the economic factors that affect resource use, & estimates the costs & benefits (to farmers, consumers, & the government) of meeting conservation & environmental goals. Charts & tables.
Download or read book Treatise on Estuarine and Coastal Science written by and published by Academic Press. This book was released on 2012-03-06 with total page 4604 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of estuaries and coasts has seen enormous growth in recent years, since changes in these areas have a large effect on the food chain, as well as on the physics and chemistry of the ocean. As the coasts and river banks around the world become more densely populated, the pressure on these ecosystems intensifies, putting a new focus on environmental, socio-economic and policy issues. Written by a team of international expert scientists, under the guidance of Chief Editors Eric Wolanski and Donald McClusky, the Treatise on Estuarine and Coastal Science, Ten Volume Set examines topics in depth, and aims to provide a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Most up-to-date reference for system-based coastal and estuarine science and management, from the inland watershed to the ocean shelf Chief editors have assembled a world-class team of volume editors and contributing authors Approach focuses on the physical, biological, chemistry, ecosystem, human, ecological and economics processes, to show how to best use multidisciplinary science to ensure earth's sustainability Provides a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Features up-to-date chapters covering a full range of topics
Download or read book Closing nutrient cycles written by Usman Akram and published by Linköping University Electronic Press. This book was released on 2020-08-20 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adequate and balanced crop nutrition – with nitrogen (N), phosphorus (P), and potassium (K) – is vital for sustainable crop production. Inadequate and imbalanced crop nutrition contributes to the crop yield gaps – a difference in actual and potential crop yield. Yield gap is one of the many causes of insufficient food production, thus aggravating hunger and malnourishment across the globe. On the other hand, an oversupply of nutrients is highly unsustainable, in terms of both resource conservation and global environmental health. A decreasing excreta recycling in crop production is one of the many reasons for nutrient imbalances in agriculture. Previous studies show that increasing agricultural specialization leads to spatial separation of crop and animal production. Increasing distance between excreta production and crop needs is one of the leading factors that cause reduced excreta recycling. Studies focusing on excreta recycling show that a substantial barrier to a more efficient excreta nutrient reuse is the expensive transportation of bulky volumes of excreta over long distances. In order to overcome that barrier, more detailed spatial estimates of distances between excreta production and crop nutrient needs, and the associated costs for complete excreta transport in an entire country are needed. Hence, the overall aim of this thesis was to quantify the amount of nutrients in the excreta resources compared to the crop nutrient needs at multiple scales (global, national, subnational, and local), and to analyze the need for excreta transports, total distances and costs, to meet the crop nutrient needs in a country. On the global scale, annual (2000-2016) excreta supply (livestock and human) could provide at least 48% of N, 57% of P, and 81% of K crop needs. Although excreta supply was not enough to cover the annual crop nutrient needs at the global scale, at least 29 countries for N, 41 for P, and 71 for K had an excreta nutrient surplus. When including the annual use of synthetic fertilizers, at least 42 additional countries had a N surplus, with the equivalent figures for P being 17 countries, whereas 8 additional countries attained a K surplus. At the same time, when accounting for the use of synthetic fertilizers, each year, at least 57 countries had an N deficit, 70 a P deficit, and 51 countries a K deficit, in total equivalent to 14% of global N and 16% of each P and K crop needs. The total surplus in other countries during the period was always higher than the deficit in the countries with net nutrient deficits, except for P for some years. Unfortunately, both the deficits of the deficit countries and surpluses of the surplus countries were increasing substantially during the 17 years. Such global divergence in nutrient deficits and surpluses have clear implications for global food security and environmental health. A district-scale investigation of Pakistan showed that the country had a national deficit of 0.62 million tons of P and 0.59 million tons of K, but an oversupply of N. The spatial separation was not significant at this resolution; only 6% of the excreta N supply needed to be transported between districts. Recycling all excreta, within and between districts, could cut the use of synthetic N to 43% of its current use and eliminate the need for synthetic K, but there would be an additional need of 0.28 million tons of synthetic P to meet the crop nutrient needs in the entire country. The need for synthetic fertilizers to supplement the recycled excreta nutrients would cost USD 2.77 billion. However, it might not be prohibitively expensive to correct for P deficiencies because of the savings on the costs of synthetic N, and K. Excreta recycling could promote balanced crop nutrition at the national scale in Pakistan, which in turn could eliminate the nutrient-related crop yield gaps in the country. The municipal-scale investigation using Swedish data showed that the country had a national oversupply of 110,000 tons of N, 6,000 tons of P, and 76,000 tons of K. Excreta could provide up to 75% of N and 81% of P, and more than 100% of the K crop needs in the country. The spatial separation was pronounced at the municipal scale in the country. Just 40% of the municipalities produced over 50% of the excreta N and P. Nutrient balance calculations showed that excreta recycling within municipalities could provide 63% of the P crop needs. Another 18% of the P crop needs must be transported from surplus municipalities to deficit municipalities. Nationally, an optimized reallocation of surplus excreta P towards the P deficit municipalities would cost USD 192 million for a total of 24,079 km truck transports. The cost was 3.7 times more than the total NPK fertilizer value transported, and that met the crop nutrient needs. It was concluded that Sweden could potentially reduce its dependence on synthetic fertilizers, but to cover the costs of an improved excreta reuse would require valuing the additional benefits of recycling. An investigation was also done to understand the effect of the input data resolution on the results (transport needs and distances) from a model to optimize excreta redistribution. The results showed that the need for excreta transports, distances, and spatial patterns of the excreta transports changed. Increasing resolution of the spatial data, from political boundaries in Sweden and Pakistan to 0.083 decimal grids (approximately 10 km by 10 km at the equator), showed that transport needs for excreta-N increased by 12% in Pakistan, and the transport needs for excreta-P increased by 14% in Sweden. The effect of the increased resolution on transport analysis showed inconsistency in terms of the excreta total nutrient transportation distance; the average distance decreased by 67% (to 44 km) in Pakistan but increased by 1 km in Sweden. A further increase in the data resolution to 5 km by 5 km grids for Sweden showed that the average transportation distance decreased by 9 km. In both countries, increasing input data resolution resulted in a more favorable cost to fertilizer value ratios. In Pakistan, the cost of transport was only 13% of the NPK fertilizer value transported at a higher resolution. In Sweden, the costs decreased from 3.7 (at the political resolution) to slightly higher than three times of the fertilizer value transported in excreta at the higher data resolution. This Ph.D. thesis shows that we could potentially reduce the total use of synthetic fertilizers in the world and still reduce the yield gaps if we can create a more efficient recycling of nutrients both within and between countries, and a more demand adapted use of synthetic fertilizers. Livsmedelsproduktion är grunden för vårt samhälle idag och för den utveckling som skett det senaste århundrandet. Idag är vi åtta miljarder människor i världen med en produktion och handel med livsmedel, där knappt en miljard lever under hunger och svält. Inom de närmaste decennierna förväntas världens befolkning fortsätta växa och stanna av på omkring 11 till 12 miljarder människor under senare hälften av 2000-talet. För att klara livsmedelsförsörjningen bättre idag, och ännu mer så i framtiden, krävs att vi hittar former för att återföra skördade näringsämnen, som fosfor, kväve och kalium, tillbaka till åkermarken. Många av dessa näringsämnen är ändliga resurser som dessutom bidrar till övergödning om de läcker ut till andra habitat. I dag återfinns det mesta av dessa näringsämnen i gödsel, mänsklig exkreta och rötslam från avloppsreningsverk. Avhandlingen har studerat förutsättningarna för att sluta en större del av näringsämnens cykler i Sverige och Pakistan genom återföring av gödsel och mänsklig exkreta till jordbruksmark, samt utifrån detta även dragit slutsatser om de globala förutsättningar och effekterna av att sluta kretslopp för näringsämnen. Effekterna av att förbättra återförsel av näringsämnen till åkermark innefattar en minskad belastning i miljön som resultat av minskad användning av handelsgödsel, minskad användning av energi för produktion av handelsgödsel, samt framför allt ökade möjligheter för en långsiktigt hållbar hög skörd på åkerarealen. Det finns dock energikostnader vid återförsel av näringsämnen till följd av många och tunga transporter. Avhandlingen har därför analyserat transportkostnader för effektiv återvinning av näringsämnen från djurhållning och mänsklig exkreta och hur stor del av gödselbehovet som kan täckas av dessa återförda näringsämnen. Speciellt har avhandlingen också studerat hur viktigt det är att ta hänsyn till i vilken skala man skall studera problemet, dvs om det är data på gödselbehov och tillgång som är lokala - ända ner på enskilda fält och gårdar - regionala eller nationella som man skall utgå från när man söker efter effektiva lösningar för att sluta näringsämnes cykler. Resultaten visar att större delen av gödselbehovet i både Pakistan och Sverige kan täckas genom återvinning av stallgödsel och mänsklig exkreta. I Sverige kan 81% av fosforbehovet täckas på det viset. Transporterna sker i första hand inom kommuner, 63% av behovet, medan de resterande 18% av behovet som kan täckas kräver transporter som är längre och sker mellan kommuner. Kostnaden för transporterna är däremot höga och motsvarar mer än tre gånger kostnaden för motsvarande handelsgödsel. I Pakistan är kostnadsbilden annorlunda, bl.a. eftersom lönekostnaderna är lägre och handelsgödsel är dyrare än i Sverige. Avhandlingen visar att kostnaden för transporter av gödsel i Pakistan skulle motsvara enbart 13% av kostnaden för motsvarande mängd handelsgödsel. Det mesta av återförandet av näringsämnen sker inom distrikt, till exempel är det bara 6% av kvävebehovet som behöver täckas av transporter utanför distrikten. Pakistans handelsgödselanvändning, och därmed kostnad för detta, skulle vid en effektiv återvinning av näringsämnen kunna reduceras ned till 43% av dagens kostnader för kvävegödsel, för fosfor behövs det 0.28 miljoner ton och behovet av kaliumgödsling skulle helt försvinna. Det krävs därmed handelsgödsel motsvarande 2.77 miljarder USD, vilket till del skulle kunna kompenseras av minskade totala kostnader för kväve- och kaliumgödsel. En sådan återföring av näringsämnen i Pakistan skulle också medföra en högre gödseltillförsel till jordbruket och därmed en möjlighet att reducera skördegapet i landet. Skördegapet i Pakistan är betydande med veteskördar kring 25–30% av de möjliga, och dessa skördegap anses bero just på för små gödselgivor. Pakistan har också tydliga problem med livsmedelsförsörjning på grund av dagens skördegap med 20% av en befolkning på 200 miljoner som är undernärda. För Sveriges del är produktionen och avkastningen per areal till följd av gödsling redan hög. En mer effektiv återförsel av näringsämnen i Sverige skulle därför i första hand bidra till att minska användning av handelsgödsel och därmed begränsa användning av ändliga resurser som fosfor. Analyserna i avhandlingen visar till exempel att i Sverige skulle användning av fosfor som handelsgödsel kunna minska med 67% om återförsel av stallgödsel och mänsklig exkreta effektiviserades. Analyser av globala data för år 2000 – 2016 visar att den årliga tillgången på näring i gödsel (från djur och människor) motsvarar minst 48% av grödornas N behov, 57% av P behovet och 81% av K behovet. Även om den total mängden näring i stallgödsel och mänsklig exkreta inte räcker för att täcka det årliga globala behovet av näring, så visar data på ett överskott på N i minst 29 länder, ett överskott på P i minst 41 länder och 71 länder har ett K-överskott i stallgödsel och exkreta. Om man dessutom räknar in användningen av handelsgödsel blir det ytterligare 42 länder som har överskott på N, 17 länder till med P-överskott och 8 ytterligare med K-överskott. En stor del av resterande länder har ett underskott av näringsämnen (när man summerar gödsel, mänsklig exkreta och handelsgödsel), 57 länder har brist på N, 70 länder behöver mer P och 51 har brist på K i sitt jordbruk, och har därmed lägre skördar än möjligt. Det totala överskottet av näringsämnen i de andra länderna under denna period motsvarar dock rätt väl den brist som länder med underskott uppvisar. Tyvärr är trenden den att de länder som visade på överskott av näringsämnen år 2000 har sammantaget tydligt ökat på överskottet till 2016, medan även underskotten har ökat i flera av länderna med bristande tillförsel av N, P eller K. Sådana globala obalanser har tydliga implikationer för den framtida matförsörjningen och för miljön. Avhandlingen visar att vi idag skulle kunna använda mindre handelsgödsel totalt i världen, och ändå reducera de skördegap som finns, om vi skapar en effektiv återförsel av näringsämnen såväl inom som mellan länder och ett mer behovsanpassat användande av handelsgödsel.
Download or read book Improving Potassium Recommendations for Agricultural Crops written by T. Scott Murrell and published by Springer Nature. This book was released on 2020-12-14 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book highlights concepts discussed at two international conferences that brought together world-renowned scientists to advance the science of potassium (K) recommendations for crops. There was general agreement that the potassium recommendations currently in general use are oversimplified, outdated, and jeopardize soil, plant, and human health. Accordingly, this book puts forward a significantly expanded K cycle that more accurately depicts K inputs, losses and transformations in soils. This new cycle serves as both the conceptual basis for the scientific discussions in this book and a framework upon which to build future improvements. Previously used approaches are critically reviewed and assessed, not only for their relevance to future enhancements, but also for their use as metrics of sustainability. An initial effort is made to link K nutrition in crops and K nutrition in humans. The book offers an invaluable asset for graduate students, educators, industry scientists, data scientists, and advanced agronomists.
Download or read book Determinants and Implications of the Growing Scale of Livestock Farms in Four Fast growing Developing Countries written by Christopher L. Delgado and published by Intl Food Policy Res Inst. This book was released on 2008-01-01 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapid growth in consumer demand for livestock offers an opportunity to reduce poverty among smallholder livestock farmers in the developing world. These farmers' opportunity may be threatened, however, by competition from larger-scale farms. This report assesses the potential threat, examining various forms of livestock production in Brazil, India, the Philippines, and Thailand. Findings show that the competitiveness of smallholder farms depends on the opportunity cost of family labor and farmers' ability to overcome barriers to the acquisition of production- and market-related information and assets. Pro-poor livestock development depends, therefore, on the strengthening of institutions that will help smallholders overcome the disproportionately high transaction costs in securing quality inputs and obtaining market recognition for quality outputs. These and other findings make this report a useful guide for researchers and others concerned with the opportunities and risks of smallholder livestock farming.
Download or read book Agricultural Resources and Environmental Indicators written by Economic Research Service Reference Center (U.S.) and published by . This book was released on 1994 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nutrient Management written by Stuart Dumay Klausner and published by . This book was released on 1997 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Methods for Assessment of Soil Degradation written by Rattan Lal and published by CRC Press. This book was released on 2020-11-26 with total page 573 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil degradation has serious global impacts on agronomic, economic, and sociopolitical conditions, however, statistics regarding the degree of these impacts has been largely unreliable. This book aims to standardize the methodology for obtaining reliable and objective data on soil degradation. It will also identify and develop criteria for assessing the severity of soil degradation, providing a realistic scenario of the problem.
Download or read book Estuarine Ecology written by Byron C. Crump and published by John Wiley & Sons. This book was released on 2022-10-07 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Estuarine Ecology A detailed and accessible exploration of the fundamentals and the latest advances in estuarine ecology In the newly revised third edition of Estuarine Ecology, a team of distinguished ecologists presents the current knowledge in estuarine ecology with particular emphasis on recent trends and advances. The book is accessible to undergraduate students while also providing a welcome summary of up-to-date content for a more advanced readership. This latest edition is optimized for classroom use, with a more intuitive mode of presentation that takes into account feedback from the previous edition’s readers. Review questions and exercises have been added to assist in the learning and retention of complex concepts. Estuarine Ecology remains the gold standard for the discipline by taking stock of the manifold scientific breakthroughs made in the field since the last edition was written. It also offers: Thorough introductions to estuarine geomorphology, circulation, and chemistry In-depth treatments of estuarine primary and secondary production, including coastal marshes and mangrove wetlands A holistic view of estuarine ecosystems, their modeling and analysis, as well as the impact of human activities and climate change A companion website with detailed answers to exercise questions Perfect for students of estuarine ecology, environmental science, fisheries science, oceanography, and natural resource management, Estuarine Ecology will also earn a place in the libraries of professionals, government employees, and consultants working on estuary and wetlands management and conservation.
Download or read book Nutrient Dynamics in Five Off stream Reservoirs in the Lower South Platte River Basin March September 1995 written by Lori A. Sprague and published by . This book was released on 2002 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physiology of Nutrition and Environmental Stresses on Crop Productivity written by A. Hemantaranjan and published by Scientific Publishers. This book was released on 2014-01-01 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book has meticulous research in some of the very sensible and stirring areas of Plant Physiology-Plant Molecular Physiology are indispensably needed for holistic development of agriculture and crop production in different agroclimatic zones. It would be tremendously a productive reference book for acquiring advanced knowledge by post-graduate and Ph.D. scholars in response to the innovative courses in Plant Physiology, Plant Biochemistry, Plant Molecular Biology, Plant Biotechnology, Environmental Sciences, Plant Pathology, Microbiology, Soil Science & Agricultural Chemistry, Agronomy, Horticulture, and Botany.