Suchergebnisse

Tomato is one of the most popular vegetables, with high nutrient demand. The nutrient concentration can vary depending on the development phase, cultivation system, temperature, soil conditions, luminosity, relative humidity and management practices. The aim of this work was to characterize cherry tomato visual symptoms of deficiency, as well as the effect of nutritional restriction on the development and nutrient concentration of plants cultivated in nutrient solution. Plants of the cherry tomato, cultivar Sindy, were grown in green house. We have used eleven treatments, one control with complete nutrient solution and the other ten omitting respectively the nutrients nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, boron, copper, zinc and iron. The experiment was performed in randomized design with three repetitions. After 60 days, the plants were removed from the solutions and their main symptoms were photographed and described. The traits evaluated were: total dry matter yield, dry matter of leaves, dry matter of stems and dry matter of roots; number of leaves, number of inflorescences; number of fruits and root volume. The concentration and accumulation of nutrients: nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, boron, copper, zinc and iron in leaves, stems and roots were evaluated. Nutrient concentration and accumulation were influenced by the deficiencies imposed. The visual symptoms of deficiency that had appeared firstly were those of phosphorus, boron and iron, respectively. The omissions of the nutrients nitrogen, magnesium and boron were the ones that most compromised the dry matter production of the cherry tomato plants.

The Food Stamp Program (FSP) is designed to increase the food expenditures & the diet status of low-income households. Here, data from the Special Low-Income Component of the 1977/78 Nationwide Food Consumption Survey were utilized to estimate effects of FSP participation on food expenditures, nutrient availability, & nutrient intake. The estimation procedure utilized a principal components index for characterizing availability & intake of the included nutrients. Results show that FSP participation & FSP bonus increased food expenditures & improved the nutritional status of diets of low-income household members. Nutrient availability & intake levels for FSP participants were increased by as much as 10-15% per week for selected nutrients. 6 Tables, 22 References. Modified HA

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.

1. Introduction -- 1.1 Nature and Origin of Anutrients in the Diet -- 1.2 Potential Carcinogens in Foods -- 1.3 Pharmacological Agents (Drugs) -- 1.4 Clinical Implications of Induced Rate of Metabolism of Foreign Compounds -- 2. The Fate of Anutrients in the Body -- 2.1 Metabolism of Foreign Compounds -- 2.2 Nutritional Factors Affecting the Metabolism ofAnutrients -- 2.3 Non-nutritional Dietary Factors Affecting the Metabolism of Anutrients -- 3. Nutritional Consequences of Drug Therapy -- 3.1 Drugs Affecting Food Intake -- 3.2 Drugs Affecting Absorption -- 3.3 Drugs Affecting Carbohydrate Metabolism -- 3.4 Drugs Affecting Lipid Metabolism -- 3.5 Drugs Affecting Protein and Amino Acid Metabolism -- 3.6 Drugs and Vitamin Interactions -- 3.7 Drug and Mineral Interactions -- 3.8 Conclusions -- 4. Alcohol and Nutrition -- 4.1 Alcohol Metabolism -- 4.2 Metabolic Effectsof Alcohol in the Liver -- 4.3 Alcohol and Malnutrition -- 4.4 Alcohol-related Conditions -- 5. Possible Adverse Effects of the Pharmacological Use of Vitamins -- 5.1 Fat-soluble Vitamins -- 5.2 Water-soluble Vitamins -- 5.3 Conclusions -- 6. Drug-Food Interactions -- 6.1 Food Reduces/Delays Drug Absorption -- 6.2 Food Increases Drug Absorption -- 6.3 Food Affecting Urinary Excretion of Drugs -- 6.4 Adverse Reactions Caused by Food -- 7. Nutrition and Experimental Carcinogenesis -- 7.1 Vitamin A (Retinol) -- 7.2 ?-Carotene -- 7.3 Vitamin E(?-Tocopherol) -- 7.4 Selenium -- 7.5 Vitamin C (Ascorbic Acid) -- 7.6 Conclusions -- 8. General Conclusions -- References.

This book presents a comprehensive overview of nutrient cycling processes and their importance for plant growth and ecosystem sustainability. The book combines fundamental scientific studies and devised practical approaches. It contains contributions of leading international authorities from various disciplines resulting in multidisciplinary approaches, and all chapters have been carefully reviewed. This volume will support scientists and practitioners alike.

"This study focuses on sustainability impacts as wastewater treatment plants implement treatment technologies to meet increasingly stringent nutrient limits. The objective is to determine if a point of "diminishing returns" is reached where the sustainability impacts of increased levels of nutrient removal outweigh the benefits of better water quality."--Page v

To quantify the micronutrient deficiencies and their overtime trends, food quantities reported to be consumed in HIES surveys data during 1991-92 and 2011-12 are converted into major and micronutrients using the FAO Food Composition Table for Pakistan. To see the impact of different price and income support policies on micronutrient consumption, nutrient demand elasticities are estimated for 2011-12 for carbohydrates (energy), protein, calcium, vitamin A, vitamin C, vitamin B1, vitamin B2, and Niacin. The Almost Ideal Demand System (AIDS) is applied to estimate the demand elasticities of the eight food groups which are then converted into nutrient demand elasticities using the transformation of Hunag (1996). On average, per capita consumptions of almost all micronutrients are deficient compared to their respective recommended levels. Our analysis suggest that income support to the poor in Pakistan through programmes like BISP would have been much more effective to eradicate nutrient deficiency, if deficient nutrient(s) are targeted and support is provided to those foods having highest demand elasticity for that nutrient. For example, the promotion of wheat and other cereals are important to eradicate energy deficiency, and promotion of vegetables, fruits, and milk are particularly important in eradicating vitamin A, C and iron deficiencies. These commodities are also high value crops for farmers, thus the price support in these crops will also impact micronutrient consumption through income effect.

28 pages ; We present the historical development of the nutrient stream concept, from the initial ideas on the nutrient‐bearing stratum and the transport of inorganic nutrients by the Gulf Stream to the large‐scale inorganic and organic connections in the entire Atlantic Ocean. We mostly analyze and discuss available literature but also present some novel calculations using cruise data and the velocity fields from numerical re‐analysis data. We first examine and discuss the structure of the Gulf Nutrient Stream, the significance of boundary exchange, and the importance of epipycnal and diapycnal processes. We then move to explore the subtropical and remote pathways into the Gulf Nutrient Stream, including the effect of the returning limb of the global overturning circulation, and end up reviewing the concept of nutrient irrigation of the subpolar gyre and its relevance in the spring–fall maintenance of the spring bloom. We close the chapter with some thoughts on the role of streams in the Earth system, as the key conduit for recycling properties within any ocean subsystem while simultaneously connecting the different subsystems, hence bringing about the complexity of the living planet ; This research has been supported by the Spanish government through project VA-DE-RETRO (reference number CTM2014-56987-P). Ignasi VallèsCasanova and Dorleta Orúe-Echeverria have been supported by scholarships from the Spanish government, respectively from the FPI and FPU programs