Gotowe bibliografie tematyczne / Nutrient additions

Gotowa bibliografia na temat „Nutrient additions”

Autor: Grafiati
Data publikacji: 4 czerwca 2021
Data aktualizacji: 20 lutego 2023

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Artykuły w czasopismach na temat "Nutrient additions"

1

Anderson, Wendy B., i William G. Eickmeier. "Physiological and morphological responses to shade and nutrient additions of Claytonia virginica (Portulacaceae): implications for the "vernal dam" hypothesis". Canadian Journal of Botany 76, nr 8 (1.08.1998): 1340–49. http://dx.doi.org/10.1139/b98-134.

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Because of their unique phenology and physiology, spring ephemeral herbs are believed to play an important role in intrasystem nutrient cycling in deciduous forest ecosystems. It was hypothesized that they function as a "vernal dam" by temporarily sequestering nutrients and preventing leaching from the system during a period of high nutrient availability. However, spring ephemerals require high-irradiance growing conditions. How do their physiological and morphological responses to ambient light and shade limit their ability to sequester excess nutrients? We performed field experiments using Claytonia virginica L. as a model to test several responses to shade and increasing levels of nutrient additions. We also examined the biomass responses and nutrient storage capacities of other spring ephemeral herbs. In C. virginica, shading reduced ribulose 1,5-bisphosphate carboxylase-oxygenase (Rubisco) activity, photosynthesis rate, specific leaf weight, leaf width/length (W/L), and biomass; nutrient additions increased W/L and biomass only under unshaded conditions. Other herbs responded similarly but reached maximum biomass at lower nutrient addition levels than C. virginica. Shading reduced and nutrient additions increased nitrogen and phosphorus concentrations in both C. virginica and other herbs. Shaded herbs generally reached nutrient saturation at lower nutrient addition levels than unshaded herbs. Overall, unshaded plants sequestered larger amounts of nutrients than shaded plants. This pattern is best explained by a reduction in biomass under shaded conditions. We concluded that C. virginica and other spring herbs, although important components in forest nutrient cycling in the early spring, are limited in their capacity to store excess nutrients, particularly when shaded.Key words: Claytonia virginica, nutrient cycling, spring ephemerals, vernal dam.
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Ebel, Jonathan D., Amy M. Marcarelli i Andre E. Kohler. "Biofilm nutrient limitation, metabolism, and standing crop responses to experimental application of salmon carcass analog in Idaho streams". Canadian Journal of Fisheries and Aquatic Sciences 71, nr 12 (grudzień 2014): 1796–804. http://dx.doi.org/10.1139/cjfas-2014-0266.

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Dramatic declines of Pacific salmon (Oncorhynchus spp.) populations have decreased delivery of marine-derived material to Pacific Northwest streams where juvenile salmon reside. Managers use artificial nutrient additions to increase juvenile salmon growth and survival and typically assume nutrient-driven increases in biofilm production are an important pathway by which nutrients become available to higher trophic levels. To evaluate how biofilms respond to additions of salmon carcass analog, a pasteurized, processed form of nutrient mitigation materials, we quantified biofilm nutrient limitation, benthic and whole-stream metabolism, and biofilm standing crops before and following experimental additions in tributaries of the Salmon River, Idaho, USA. Biofilm nutrient limitation did not change and standing crop did not increase in response to analog additions at two different levels (low, 30 g·m−2; or high, 150 g·m−2) within 1 month of addition. In contrast, whole-stream and benthic primary productivity and respiration increased in a high-analog treated segment, but did not increase in a low-analog treated segment. Together, our results suggest that metabolism may be a more appropriate tool for assessing the ecosystem effects of nutrient additions than biofilm standing crop or nutrient limitation, which are constrained by a variety of abiotic and biotic factors like hydrology and grazing.
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Wrenn, Brian A., Hao Zheng, Eugene S. Kohar, Kenneth Lee i Albert D. Venosa. "Effect of Pulsed Additions of Nutrients on Oil Biodegradation in Continuous-Flow Beach Microcosms". International Oil Spill Conference Proceedings 2001, nr 1 (1.03.2001): 339–44. http://dx.doi.org/10.7901/2169-3358-2001-1-339.

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ABSTRACT Bioremediation of oil-contaminated shorelines can be effected by providing sufficient quantities of certain rate-limiting nutrients, especially nitrogen and phosphorus. Although stoichiometry, based on the determination of optimal C:N:P ratios from batch oil-biodegradation experiments, traditionally has been the primary method for estimating required nutrient dosages, recent research suggests that nutrient uptake and microbial growth kinetics may be more important in determining the success of oil spill bioremediation. Because nutrient washout can be relatively rapid in intertidal environments, nutrient application strategies must consider the relative rates of nutrient washout and uptake by microorganisms. Because there may be significant differences between ammonium and nitrate with respect to both of these processes, a laboratory investigation of the performance of these two nitrogen sources was conducted in continuous-flow beach microcosm reactors. The behavior of these nutrients was compared under abiotic conditions to determine whether ammonium could be retained in oil-contaminated beaches longer than nitrate by ion exchange. Their ability to support oil biodegradation under continuous and intermittent feeding conditions also was compared. No differences between ammonium and nitrate could be detected based on either criterion, but faster oil biodegradation was observed under pulse-feeding conditions than when the nutrients were supplied continuously. The relatively poor performance of the continuously fed systems was attributed to nutrient limitation because the nutrient input rate was less than the nutrient demand rate.
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Zhuang, Liyan, Qun Liu, Ziyi Liang, Chengming You, Bo Tan, Li Zhang, Rui Yin, Kaijun Yang, Roland Bol i Zhenfeng Xu. "Nitrogen Additions Retard Nutrient Release from Two Contrasting Foliar Litters in a Subtropical Forest, Southwest China". Forests 11, nr 4 (27.03.2020): 377. http://dx.doi.org/10.3390/f11040377.

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Litter decomposition plays a critical role in regulating biogeochemical cycles in terrestrial ecosystems and is profoundly impacted by increasing atmospheric nitrogen (N) deposition. Here, a N manipulation experiment was conducted to explore the effects of N additions (0 kg N ha−1 yr−1, 20 kg N ha−1 yr−1 and 40 kg N ha−1 yr−1) on decay rates and nutrients release of two contrasting species, the evergreen and nutrient-poor Michelia wilsonii and the deciduous and nutrient-rich Camptotheca acuminata, using a litterbag approach at the western edge of the Sichuan Basin of China. The decay rate and the mineralization of N and phosphorus (P) was faster in nutrient-rich C. acuminata litter than in nutrient-poor M. wilsonii litter, regardless of N regimes. N additions tended to decrease the decay constant (k value) in M. wilsonii litter, but had no effect on C. acuminata litter. N additions had no significant effects on carbon (C) release of both litter types. N additions showed negative effects on N and P release of M. wilsonii litter, particularly in the late decomposition stage. Moreover, for C. acuminata litter, N additions did not affect N release, but retarded P release in the late stage. N additions did not affect the C:N ratio in both litter types. However, N additions—especially high-N addition treatments—tended to reduce C:P and N:P ratios in both species. The effect of N addition on N and P remaining was stronger in M. wilsonii litter than in C. acuminata litter. The results of this study indicate that N additions retarded the nutrients release of two foliar litters. Thus, rising N deposition might favor the retention of N and P via litter decomposition in this specific area experiencing significant N deposition.
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Benjamin, Joseph R., J. Ryan Bellmore, Emily Whitney i Jason B. Dunham. "Can nutrient additions facilitate recovery of Pacific salmon?" Canadian Journal of Fisheries and Aquatic Sciences 77, nr 10 (październik 2020): 1601–11. http://dx.doi.org/10.1139/cjfas-2019-0438.

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Multiple restoration actions have been implemented in response to declining salmon populations. Among these is the addition of salmon carcasses or artificial nutrients to mimic marine-derived nutrients historically provided by large spawning runs of salmon. A key assumption in this approach is that increased nutrients will catalyze salmon population growth. Although effects on aquatic ecosystems have been observed during treatments, it is unclear whether permanent population increases for salmon will occur. To test this assumption and address associated uncertainties, we linked a food web model with a salmon life cycle model to examine whether carcass additions in a river reach would improve conditions for salmon in the long term. Model results confirmed immediate increases in the biomass of periphyton, macroinvertebrates, and fish during carcass additions. In turn, juvenile salmon grew larger and experienced improved freshwater and smolt survival, which translated to a greater number of adults returning to spawn. However, once additions ceased, salmon abundance returned to pretreatment levels, which, based on our model, is owing to a combination of instream and out-of-basin factors. Overall, results of this work suggest that benefits during carcass and nutrient additions may not translate into persistent productivity of salmon unless additions are sustained indefinitely or other limiting factors are addressed.
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Timmer, V. R., i G. Armstrong. "Growth and nutrition of containerized Pinusresinosa at exponentially increasing nutrient additions". Canadian Journal of Forest Research 17, nr 7 (1.07.1987): 644–47. http://dx.doi.org/10.1139/x87-105.

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Containerized red pine (Pinusresinosa Ait.) seedlings were reared on different fertility regimes that compared conventional applications of a recommended 39 mg N per seedling as a complete nutrient solution (175 mg N•L−1) with more frequent applications of an equal, one-half, or one-quarter amount of nutrients delivered at exponentially increasing solution concentrations over the same time period. Height growth, dry matter production, and root development at the end of the greenhouse rotation was significantly greater for seedlings receiving nutrients at exponentially rather than constantly increasing rates, although shoot growth among the three exponential treatments did not differ significantly. The increased yield was attributed to improved seedling nutrition as fertilizer addition rates better matched exponential growth development and nutrient consumption of the plants. The results indicate that superior seedlings can be grown successfully at low concentrations of nutrient solution, applying only one-quarter of the fertilizer dose conventionally used for container stock production.
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Perrin, Chris J., Max L. Bothwell i Pat A. Slaney. "Experimental Enrichment of a Coastal Stream in British Columbia: Effects of Organic and Inorganic Additions on Autotrophic Periphyton Production". Canadian Journal of Fisheries and Aquatic Sciences 44, nr 6 (1.06.1987): 1247–56. http://dx.doi.org/10.1139/f87-147.

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Periphyton accumulation rates and alkaline phosphatase activity were examined in reaches of the Keogh River, British Columbia, following additions of grain and inorganic fertilizer as separate treatments during spring–summer 1981. Two different levels of N and P addition were used: one to attain ambient N and P concentrations of 200 and 15 μg∙L−1, respectively, and the other to attain 400 and 20 μg∙L−1, respectively. Grain (rolled barley) was added monthly at 280 g∙m−2. N and P additions increased chlorophyll a accrual rates by more than an order of magnitude. Diatoms dominated the periphyton community until midsummer. In July and most of August, the relative importance of chlorophytes increased and biomass levels declined markedly in spite of continued nutrient additions. Grain additions resulted in no detectable change in periphyton accrual, but alkaline phosphatase activity increased by 35% over control levels. These results suggest that additions of labile organic matter to nutrient-deficient coastal streams can increase autotrophic P deficiency. Based on responses of juvenile salmonids, additions of inorganic nutrients to increase autotrophic production can maximize trophic enhancement in nutrient-deficient streams.
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Christoforou, Anthea, Sheida Norsen, Jodi Bernstein i Mary L’Abbe. "Examining the Prevalence, Nutritional Quality and Marketing of Foods with Voluntary Nutrient Additions in the Canadian Food Supply". Nutrients 13, nr 9 (5.09.2021): 3115. http://dx.doi.org/10.3390/nu13093115.

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Foods with voluntary nutritional additions are a fast-growing sector of the global food industry. In Canada, while the addition of nutrients to foods has been regulated through fortification regulations, parallel policies which aim to encourage product innovation have also allowed for the voluntary addition of nutrients and other novel ingredients to ‘supplemented’ and ‘functional’ foods. Concerns have been raised that the consumption of these products may have negative repercussions on population health, such as high nutrient intakes inappropriate for certain population subgroups (e.g., children) and the shifting of dietary patterns to include more unhealthy foods. The aim of this study was to evaluate the prevalence, nutritional quality, and marketing characteristics of foods with added nutrients in the Canadian market. We found many nutritionally-enhanced foods contained high levels of nutrients beyond recommended intakes, despite these nutrients having no evidence of inadequacy in the Canadian population. Additionally, a large proportion of foods with added nutrients had poor nutrient profiles (were deemed ‘less healthy’ than their non-enhanced counterparts) and carried heavy marketing on their labels, regardless of their nutritional quality. Taken together these findings raise concerns about foods with voluntary nutrient additions and suggest the need to further investigate consumer attitudes and decision-making towards these foods.
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Anderson, Wendy B., i William G. Eickmeier. "Nutrient resorption in Claytonia virginica L.: implications for deciduous forest nutrient cycling". Canadian Journal of Botany 78, nr 6 (1.06.2000): 832–39. http://dx.doi.org/10.1139/b00-056.

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According to the vernal dam hypothesis, spring ephemeral herbs temporarily sequester large nutrient pools in deciduous forests prior to canopy closure and return the nutrients to the soil following senescence of aboveground tissues. However, many species resorb nutrients from their leaves back to belowground tissues during senescence, and the degree of resorption is often associated with soil nutrient availability. Species that store large proportions of their absorbed nutrients between years are not participating in the temporary sequestering and rapid recycling of nutrients implied by the vernal dam. We investigated the extent to which Claytonia virginica L. sequestered and returned nutrients to the soil in response to nitrogen (N) and phosphorus (P) availability. We tested the effect of nutrient availability on nutrient use efficiency, resorption efficiency, and resorption proficiency (% nutrient in senescent leaves) of Claytonia. Nutrient additions significantly decreased N but not P use efficiency of Claytonia, particularly as the growing season progressed. Nutrient additions also significantly reduced N resorption efficiency from 80 to 47% and decreased P resorption efficiency from 86 to 56%. N and P resorption proficiencies were also significantly lower in senesced leaves of fertilized plants: N concentrations were 2.33% when unfertilized and 4.13% when fertilized, while P concentrations were 0.43% when unfertilized versus 0.57% when fertilized. When unfertilized, Claytonia was more efficient at resorption compared with other spring herbs, but similar to other species when fertilized. However, Claytonia was much less proficient in resorbing nutrients than other reported plants, because senescent tissues maintained substantially higher concentrations of N and P, particularly when fertilized. In conclusion, Claytonia, an important spring ephemeral species, exhibits physiological responses that emphasize its role in the vernal dam by its temporary sequestration and substantial, rapid return of nutrients in deciduous forests. Adding nutrients to the site increases the total mass and the relative proportion of nutrients that Claytonia returns to the soil rather than sequestering between seasons, which ultimately increases nutrient recycling rates within the entire system.Key words: Claytonia virginica, nutrient response, resorption efficiency, nutrient cycling, spring ephemerals, vernal dam.
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Morris, Liz, Gregory Jenkins, David Hatton i Timothy Smith. "Effects of nutrient additions on intertidal seagrass (Zostera muelleri) habitat in Western Port, Victoria, Australia". Marine and Freshwater Research 58, nr 7 (2007): 666. http://dx.doi.org/10.1071/mf06095.

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Loss of seagrass habitat in many parts of the world has been attributed to increases in nutrient loading to nearshore areas. The role of excess epiphyte, macroalgal or phytoplankton growth in shading of seagrass leaves and negatively affecting seagrass health is generally agreed to be a prevalent mechanism in seagrass decline worldwide. In the present study nutrient addition experiments were undertaken at three sites in Western Port, Victoria. Nutrients were added to the water column using the controlled release fertiliser Osmocote™ in late summer 2005. The experiments ran for one month at two of the sites (Blind Bight and Hastings) and at the third site (Crib Point) the experiment ran for three months. Control and nutrient addition plots were monitored for concentrations of inorganic nutrients, number of seagrass leaves, seagrass, epiphyte and loose algal biomass and invertebrate faunal assemblages. Nutrient additions had increased ash free dry weight of seagrass leaves and loose algae at two of the three sites studied. There was also an increase in gammarid amphipod densities at the Crib Point site. We consider that Western Port seagrass habitat is sensitive to increased loads of nutrients within the water column with the Blind Bight region most at risk.
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Rozprawy doktorskie na temat "Nutrient additions"

1

Hadwen, Wade Lynton, i w. hadwen@mailbox gu edu au. "Effects of Nutrient Additions on Dune Lakes on Fraser Island, Australia". Griffith University. Australian School of Environmental Studies, 2002. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030304.091718.

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Given the rapidly increasing visitation levels to Fraser Island, there is increasing concern that tourist activities may threaten the long-term ecological health of the region's unique dune lakes. This project aimed to investigate the consequences of tourist use of Fraser Island's dune lakes and to develop appropriate monitoring tools and management objectives in light of the projected increases in visitation levels in the foreseeable future. The initial phase of this research aimed to identify the relative importance of some of the most popular dune lakes on the island as key destinations for tourists. Tourist surveys, in conjunction with the development of a Tourist Pressure Index (TPI), which quantifies logistic, social and natural variables, identified Lakes McKenzie, Allom and Birrabeen as the lakes most at risk from excessive tourist use. In addition, analyses of water quality in 15 lakes on Fraser Island aimed to determine the current trophic status of dune lakes on Fraser Island and the ecological implications of tourist use of these systems. Detailed comparisons of nutrient and chlorophyll a concentrations in five popular dune lakes in February 1990 (data from Arthington et al. 1990) and February 1999 suggested that productivity has increased significantly in the past decade. More detailed examinations of nutrient and algal variables in five popular perched dune lakes revealed that while ambient nutrient and phytoplankton chlorophyll a concentrations remained relatively stable, periphyton chlorophyll a concentrations increased over the course of the 1999-2000 summer in most lakes. Significantly, these increases were found only in heavily visited (disturbed) sites in the clear lakes examined (McKenzie and Birrabeen). In these lakes, where algal growth is likely to be only limited by nutrient availability, tourist nutrient additions may stimulate excessive periphyton production. Experimental algal bioassays identified that phytoplankton and to a lesser degree periphyton growth was stimulated by nutrient additions in all five perched dune lakes. However, the degree to which growth was stimulated was both lake and nutrient (nitrogen versus phosphorus versus nitrogen + phosphorus) dependent, highlighting the variable nature of systems within a relatively small geographic range. Since periphyton biomass was higher in heavily visited areas of lakes and was likely to be stimulated by nutrient additions by tourists, stable isotope analyses of littoral zone food webs were conducted to quantify the percent contribution of periphyton to consumer diets. There was a trend towards higher periphyton contributions in systems identified as key tourist locations (on the basis of their TPI scores) and this indicates that increasing visitation may increase the contribution of periphyton to littoral zone food webs, both via increases in the quantity and quality of periphyton as a food resource. To further explore the contribution of periphyton in littoral zone food webs of heavily visited lakes, a 15N-tracer addition experiment was conducted to establish the fate of nutrient additions within the littoral zone. Nutrients were added in quantities that mimicked those likely from tourists, to enable a realistic appraisal of the fate of tourist additions. As expected, periphyton rapidly assimilated the added 15N-tracer and was found to be the first and most significant sink for nutrients entering the littoral zone. Finally, the results from this research were used to develop a conceptual model of nutrient enrichment for perched dune lakes on Fraser Island. The model indicates that although nutrient additions from tourists may lead to undesirable increases in periphyton biomass, the degree to which this is deemed to be a detrimental ecological outcome is likely to be mediated by water level fluctuations and the consumptive capacity of grazers. Given that excessive periphyton growth is likely to be seen as negative impact of tourism, regular periphyton monitoring (biomass and percent contribution to littoral zone food webs) should be built into an updated monitoring program for this series of dune lakes. Whilst the implementation of periphyton monitoring is likely to enable the early detection of deleterious impacts of excessive tourist use, it is likely that the long-term conservation of the region will, in the future, require the implementation of strict visitation level guidelines, to ensure that the irreversible consequences of long term additions of nutrients are ameliorated.
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2

Witkowski, Edward Tadeusz Fernando. "Response of a sand-plain lowland fynbos ecosystem to nutrient additions". Doctoral thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/8408.

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Bibliography: leaves 237-258.
The effects of a complete factorial fertilizer addition of nitrogen (N), phosphorus (P) and a mixture of all essential nutrients excluding N and P (M) on various components of the soils and vegetation of a sand-plain lowland fynbos ecosystem at Pella, south-western Cape Province, South Africawere studied, namely: 1) Soil nutrient dynamics. 2) Phenology, shoot growth, reproductive output and nutrient acquisition in a proteoid (Leucospermum parile) and an ericoid (Phylica cephalantha) evergreen shrub. 3) Dry mass, phosphorus and nitrogen allocations to the various above and below ground organs of pre-reproductive and reproductive male plants of Thamnochortus punctatus (Restionaceae). 4) Litter production and nutrient return. 5) Above-ground phytomass, nitrogen and phosphorus contents of the representative plant growth forms in response to non-factorial addition of N, P and M. 6) Foliage projective cover of the representative growth forms of sand-plain lowland fynbos.
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3

Hadwen, Wade. "Effects of Nutrient Additions on Dune Lakes on Fraser Island, Australia". Thesis, Griffith University, 2002. http://hdl.handle.net/10072/368084.

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Given the rapidly increasing visitation levels to Fraser Island, there is increasing concern that tourist activities may threaten the long-term ecological health of the region's unique dune lakes. This project aimed to investigate the consequences of tourist use of Fraser Island's dune lakes and to develop appropriate monitoring tools and management objectives in light of the projected increases in visitation levels in the foreseeable future. The initial phase of this research aimed to identify the relative importance of some of the most popular dune lakes on the island as key destinations for tourists. Tourist surveys, in conjunction with the development of a Tourist Pressure Index (TPI), which quantifies logistic, social and natural variables, identified Lakes McKenzie, Allom and Birrabeen as the lakes most at risk from excessive tourist use. In addition, analyses of water quality in 15 lakes on Fraser Island aimed to determine the current trophic status of dune lakes on Fraser Island and the ecological implications of tourist use of these systems. Detailed comparisons of nutrient and chlorophyll a concentrations in five popular dune lakes in February 1990 (data from Arthington et al. 1990) and February 1999 suggested that productivity has increased significantly in the past decade. More detailed examinations of nutrient and algal variables in five popular perched dune lakes revealed that while ambient nutrient and phytoplankton chlorophyll a concentrations remained relatively stable, periphyton chlorophyll a concentrations increased over the course of the 1999-2000 summer in most lakes. Significantly, these increases were found only in heavily visited (disturbed) sites in the clear lakes examined (McKenzie and Birrabeen). In these lakes, where algal growth is likely to be only limited by nutrient availability, tourist nutrient additions may stimulate excessive periphyton production. Experimental algal bioassays identified that phytoplankton and to a lesser degree periphyton growth was stimulated by nutrient additions in all five perched dune lakes. However, the degree to which growth was stimulated was both lake and nutrient (nitrogen versus phosphorus versus nitrogen + phosphorus) dependent, highlighting the variable nature of systems within a relatively small geographic range. Since periphyton biomass was higher in heavily visited areas of lakes and was likely to be stimulated by nutrient additions by tourists, stable isotope analyses of littoral zone food webs were conducted to quantify the percent contribution of periphyton to consumer diets. There was a trend towards higher periphyton contributions in systems identified as key tourist locations (on the basis of their TPI scores) and this indicates that increasing visitation may increase the contribution of periphyton to littoral zone food webs, both via increases in the quantity and quality of periphyton as a food resource. To further explore the contribution of periphyton in littoral zone food webs of heavily visited lakes, a 15N-tracer addition experiment was conducted to establish the fate of nutrient additions within the littoral zone. Nutrients were added in quantities that mimicked those likely from tourists, to enable a realistic appraisal of the fate of tourist additions. As expected, periphyton rapidly assimilated the added 15N-tracer and was found to be the first and most significant sink for nutrients entering the littoral zone. Finally, the results from this research were used to develop a conceptual model of nutrient enrichment for perched dune lakes on Fraser Island. The model indicates that although nutrient additions from tourists may lead to undesirable increases in periphyton biomass, the degree to which this is deemed to be a detrimental ecological outcome is likely to be mediated by water level fluctuations and the consumptive capacity of grazers. Given that excessive periphyton growth is likely to be seen as negative impact of tourism, regular periphyton monitoring (biomass and percent contribution to littoral zone food webs) should be built into an updated monitoring program for this series of dune lakes. Whilst the implementation of periphyton monitoring is likely to enable the early detection of deleterious impacts of excessive tourist use, it is likely that the long-term conservation of the region will, in the future, require the implementation of strict visitation level guidelines, to ensure that the irreversible consequences of long term additions of nutrients are ameliorated.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Australian Environmental Studies
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Irvine, K. "Zooplankton ecology and the effects of nutrient additions, habitat structure and fish predation on a freshwater ecosystem". Thesis, University of East Anglia, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378900.

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Smith, Russell Stephen. "Mineral nutrient influxes and additions and their effects in a Banksia woodland ecosystem in South Western Australia". Thesis, Smith, Russell Stephen (1990) Mineral nutrient influxes and additions and their effects in a Banksia woodland ecosystem in South Western Australia. Honours thesis, Murdoch University, 1990. https://researchrepository.murdoch.edu.au/id/eprint/41520/.

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The objectives of this study were to gain information on the environmental effects of fertilizer drift. This was achieved by undertaking two separate investigations 1 firstly soil nutrient levels and vegetation composition along transects from farmland into a Banksia woodland were analysed to see how they co-varied. Secondly the effect of agricultural fertilizers on the growth, and nutrient and carbohydrate levels of selected shrub species from a Banksia woodland was investigated to determine if fertilizer stimulated shoot growth led to a reduction in root reserves which might diminish post-fire resprouting ability. The first investigation, into fertilizer drift at Dardanup Block, a conservation reserve, found that most invasive exotic pasture species were restricted to physically disturbed areas at the edge of the reserve with only Hypochaeris glabra a small wind dispersed composite being common away from the edge. Total phosphorus values were highest in the paddock and declined with increasing distance into the reserve, levels were significantly higher in samples taken 0.5 m, 10 m and 20 m into the reserve than they were from those taken 60 m from the fence. Although potassium had been applied to the paddock for over twenty years there was no apparent effect on soil available potassium values at the edge of the reserve. The levels of this mineral and also total nitrogen within the woodland were correlated with native vegetation composition. In the fertilization study the shrubs Kunzea ericifolia and Leucopogon conostephioides increased their mean biomass per new shoot in response to NPK fertilizer but not to superphosphate alone. The NPK fertilized 11 Kunzea plants connnenced shoot elongation earlier in the season than did the control plants. Increased growth was associated with higher proportions of phosphorus and potassium per unit of shoot nitrogen in Kunzea and increased K:N ratios in Leucopogon. Levels of root non-structural carbohydrates in Kunzea and Leucopogon were not affected by increased shoot growth and the relatively low root reserves in these plants and their low root:shoot ratio are consistent with their lack of resprouting ability. Stir lingia which did not significantly increase its shoot growth in response to fertilization, had substantially higher root polysaccharide levels in the NPK plots which indicates that the added nutrients stimulated a higher rate of photosynthesis. The relatively high root: shoot ratio and root non-structural carbohydrate levels of Stirlingia are probably the reason for its strong resprouting ability. From the results of these studies it is proposed that although superphosphate influx increases the levels of phosphorus on roadsides and at the edges of reserves it alone probably doesn't adversely affect the life strategies of native species, though it may favour exotic species. Longer term studies would be needed to separate the effects of continuing nutrient influx on vegetation composition from those of overfrequent burning and various other environmental changes and disturbances associated with "edge" habitats.
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Camenzind, Tessa [Verfasser]. "Responses of arbuscular mycorrhizal fungi to nutrient additions in a tropical montane forest of Southern Ecuador / Tessa Camenzind". Berlin : Freie Universität Berlin, 2016. http://d-nb.info/1098185293/34.

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Rhein-Welker, Deanna. "Performance and nutrient digestibility in weanling pigs as influenced by yeast culture, whey, and fiber additions to starter diets". Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-07292009-090510/.

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Bergholm, Johan. "Long-term effects of enhanced nitrogen and sulphate additions on soil acidification and nutrient cycling in a Norway spruce stand /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2001. http://epsilon.slu.se/avh/2001/91-576-6099-9.pdf.

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Maloney, Caitlin E. "The effects of micronutrient additions on soil invertebrate activity and community structure along a successional gradient". Bowling Green State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1498074605780196.

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Perkins, Rupert Gordon. "Phosphorus limitation in Alton Water reservoir". Thesis, University of Essex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265030.

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Książki na temat "Nutrient additions"

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Cruikshank, D. R. Effects of nutrient and acid additions on Secchi depth at the Experimental Lakes Area, 1969-1986. Winnipeg, Man: Central and Arctic Region, Dept. of Fisheries and Oceans, 1988.

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Irvine, Kenneth. Zooplankton ecology and the effects of nutrient additions, habitat structure and fish predation on a freshwater ecosystem. Norwich: University of East Anglia, 1987.

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Lee, Cheng-Sheng, Chhorn Lim, Delbert M. Gatlin i Carl D. Webster, red. Dietary Nutrients, Additives, and Fish Health. Hoboken, NJ, USA: John Wiley & Sons, Inc, 2015. http://dx.doi.org/10.1002/9781119005568.

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Renders, Eileen. Food additives, nutrients, supplements A-to-Z: A shopper's guide. Santa Fe, NM: Clear Light Publishers, 1998.

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Renders, Eileen. Food additives, nutrients, supplements A-to-Z: A shopper's guide. Santa Fe, NM: Clear Light Publishers, 1998.

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Renders, Eileen. Food additives, nutrients & supplements A-to-Z: A shopper's guide. Santa Fe, NM: Clear Light Publishers, 1999.

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1951-, Aruoma Okezie I., i Halliwell Barry, red. Free radicals and food additives. London: Taylor & Francis, 1991.

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Gregory, Sara. Bacterial production and response to nutrient addition in the Skagit River-Skagit Bay system. Bellingham, WA: Huxley College of Environmental Studies, Western Washington University, 1997.

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Cloutier, Renée R. Effects of nutrient addition mode on jack pine (Pinus banksiane Lamb.) seedling outplanting performance. Sudbury, Ont: Laurentian University, Department of Biology, 1997.

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Haas, Leonard W. Resource limitation of phytoplankton in the Virginia Chesapeake Bay and tributaries using nutrient-addition bioassays. [Gloucester Point, Va.?]: Virginia Institute of Marine Science, School of Marine Science, College of William and Mary, 1998.

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Części książek na temat "Nutrient additions"

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Vymazal, Jan, Jaroslava Komárková, Klára Řeháková, Jan Kaštovský i Marek Bastl. "Algal Responses to Long-Term Nutrient Additions". W Everglades Experiments, 261–75. New York, NY: Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-68923-4_10.

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Majumdar, Kaushik, Robert M. Norton, T. Scott Murrell, Fernando García, Shamie Zingore, Luís Ignácio Prochnow, Mirasol Pampolino i in. "Assessing Potassium Mass Balances in Different Countries and Scales". W Improving Potassium Recommendations for Agricultural Crops, 283–340. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-59197-7_11.

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AbstractEstimating nutrient mass balances using information on nutrient additions and removals generates useful, practical information on the nutrient status of a soil or area. A negative input–output balance of nutrients in the soil results when the crop nutrient removal and nutrient losses to other sinks become higher than the nutrient inputs into the system. Potassium (K) input–output balance varies among regions that have different climates, soil types, cropping systems, and cropping intensity. This chapter illustrates the farm-gate K balances in major production areas of the world and their impacts on native K fertility and crop yields. On-farm and on-station research examples show significant negative K balances in South Asia and Sub-Saharan Africa, while China, the USA, Brazil, and countries of the Latin America Southern Cone highlighted continued requirement of location-specific K application to maintain crop yields and soil K fertility status at optimum levels.
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Hamer, Ute, Karin Potthast, Wolfgang Wilcke, Hans Wullaert, Carlos Valarezo, Dorothee Sandmann, Mark Maraun, Stefan Scheu i Jürgen Homeier. "Nutrient Additions Affecting Matter Turnover in Forest and Pasture Ecosystems". W Ecosystem Services, Biodiversity and Environmental Change in a Tropical Mountain Ecosystem of South Ecuador, 297–313. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-38137-9_22.

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Murkin, Henry R., J. Bruce Pollard, Michael P. Stainton, John A. Boughen i R. D. Titman. "Nutrient additions to wetlands in the Interlake region of Manitoba, Canada: effects of periodic additions throughout the growing season". W Aquatic Birds in the Trophic Web of Lakes, 483–95. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1128-7_44.

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Buckland, B. C. "On-Line Monitoring of the Response of a Fermentation Process to Nutrient Additions". W Computer Applications in Fermentation Technology: Modelling and Control of Biotechnological Processes, 401–10. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-1141-3_45.

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Olsson, Håkan, Peter Blomqvist i Hans Olofsson. "Phytoplankton and zooplankton community structure after nutrient additions to the oligotrophic Lake Hecklan, Sweden". W The Dynamics and Use of Lacustrine Ecosystems, 147–55. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-011-2745-5_15.

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King, Ryan S., i Curtis J. Richardson. "Macroinvertebrate Responses to a Gradient of Long-Term Nutrient Additions, Altered Hydroperiod, and Fire". W Everglades Experiments, 277–319. New York, NY: Springer New York, 2008. http://dx.doi.org/10.1007/978-0-387-68923-4_11.

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Gabor, T. S., H. R. Murkin, M. P. Stainton, J. A. Boughen i R. D. Titman. "Nutrient additions to wetlands in the Interlake region of Manitoba, Canada: effects of a single pulse addition in spring". W Aquatic Birds in the Trophic Web of Lakes, 497–510. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1128-7_45.

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Manny, B. A., W. C. Johnson i R. G. Wetzel. "Nutrient additions by waterfowl to lakes and reservoirs: predicting their effects on productivity and water quality". W Aquatic Birds in the Trophic Web of Lakes, 121–32. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1128-7_12.

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de Mello, Thiago R. B., Cássia B. R. Munhoz i Mercedes M. C. Bustamante. "Effects of Nutrient Additions on the Diversity of the Herbaceous-Subshrub Layer of a Brazilian Savanna (Cerrado)". W Nitrogen Deposition, Critical Loads and Biodiversity, 147–54. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-007-7939-6_16.

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Streszczenia konferencji na temat "Nutrient additions"

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Li, J., W. L. Huang, L. Xue i Z. Y. Lie. "Effects of N and P Additions On Soil Nutrient and Biochemical Characteristics in An Acacia Mangium Stand". W 2015 International Conference on Environmental Science and Sustainable Development (ICESSD 2015). WORLD SCIENTIFIC, 2016. http://dx.doi.org/10.1142/9789814723039_0018.

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Zhang, Ning, i Weihao Wang. "Investigation of Water pH in Calcasieu Lake Area Using Regional Scale Hydrodynamic Models". W ASME 2017 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/fedsm2017-69208.

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In Southwest Louisiana, the Calcasieu Lake and surrounding water systems are the major fresh water sources to the nearby coastal wetlands and agricultural areas. There are two national wide life refuges located in both east and west sides of Calcasieu Lake. Both refuges are covered by coastal wetlands. The health of the wetland vegetation is essential to the wetland losses in the area. One of the major problems related to the health of marshes is the nutrient deficiency. In addition, the surface water system is a possible source for agriculture use that requires sufficient nutrient components in water. Understanding the transport and distribution of various nutrients in the coastal water system is very important to the above-mentioned issues. In this study, a regional scale hydrodynamic model was utilized to simulate the hydrodynamics, salinity transport and sediment transport in this major water system in Southwest Louisiana. The pH distribution in water is a good indication of many nutrient components, such as phosphorous, and is essential to understand the nutrient distributions in the target area. A pH calculation procedure was implemented in the model to determine pH values based on the salinity and other water properties. The model results can be used to indicate the dynamic change of nutrient distributions and the areas of nutrient deficiency.
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Mignone, Lindsay F., Shirley Masand, Jeffrey D. Zahn i David I. Shreiber. "A Simple, Cost-Effective Method to Improve Cell Viability in Microniche Culture Systems". W ASME 2010 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2010. http://dx.doi.org/10.1115/sbc2010-19189.

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Microfluidic networks are increasingly used to generate custom microenvironmental niches for cell culture and assays of cellular behavior. Perfusion systems are typically required to overcome diffusive limitations associated with culturing cells longer than a few hours when nutrient delivery, oxygen delivery and metabolic waste removal are required to maintain cell viability. In addition to the added complexity of experimental methods, perfusion systems can result in nonuniform nutrient delivery and subject cells to shear stresses, which may alter cell behavior and possibly cause cell death. In particular, when culturing cells within hydrogel scaffold-filled networks, as may be done in micro-tissue engineering, the need for perfusion culture also increases the likelihood of a destructive bubble entering the network. Moreover, analysis of micro-cultures frequently entails labelling with antibodies and/or fluorescent probes, which again requires controlled perfusion of the various reagents through the network. We have developed a simple technique to preserve cell viability and simplify labeling within microscale cultures without the need for perfusion. Instead of bonding a microfluidic network to glass, PDMS, or another impermeable substrate, the network is bonded to a semi-permeable microdialysis membrane, which allows free exchange of oxygen, proteins, nutrients, and waste between the microfluidic channels and culture media in static culture plates.
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Bobeck, Elizabeth. "Bioactive lipids and related nutrients in companion animal and poultry diets for reducing inflammation and improving immunity". W 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/vqxl3869.

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Beyond meeting nutritional requirements for growth and maintenance, select dietary ingredients can have additional effects, intended or not, on animal physiology and immune function. Diets can be enriched to benefit the animal, and a dual benefit can be achieved in the case of enriching animal products for the downstream human consumer. Many immune-altering nutrients are fat-soluble, including Vitamin E and D. Importantly, dietary lipids themselves can impact immune function; therefore, a focused and intentional selection of specific dietary fats, specifically omega-3 polyunsaturated fatty acids (PUFA), is one method to alter inflammatory cascades in animals consuming the diet. Examples of other related ingredients to which the immune system is responsive include zinc and probiotics. While work in human, livestock, and companion animal models is working to identify therapeutic inclusion rates for these nutrients and ingredients, it should be noted that physiological alterations are seen in both over and under-inclusion and are nutrient-specific. For example, inclusion above currently recommended levels may optimize immune function and reduce inflammation in the case of vitamin D or omega-3 PUFA, while for zinc, additional pharmacological supplementation above requirements may inhibit immune function. Importantly, when a diet is formulated to reduce overall systemic inflammation, it must be considered that important “background” functions of the immune system, including monitoring for and clearing pathogenic microbial populations, may be down-regulated due to a general reduction in immune reactivity. Continued work to understand how diet and nutrition impact immunity, and how to balance inflammation through nutrition, is an area of active research and will inform downstream users how to best use data to impact consumers of that feed in desirable ways.
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Nedyalkov, Ivaylo, Todd Guerdat, Drue Seksinsky, Sylvia Romero, Justin Stickney i Ethan Pirie. "Numerical and Experimental Investigation of Flow in Fish Tanks for Small-Scale Aquaponic Systems". W ASME 2017 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/fedsm2017-69395.

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Aquaponic systems combine recirculating aquaculture (growing of fish) with hydroponics (growing of plants in water). The fish in the recirculating aquaculture systems provide nutrients for the plants and the plants remove excess nutrients from the water, making these systems more efficient than traditional farming methods in terms of nutrient utilization. Small, recirculating aquaponic systems may provide a more sustainable and cost-effective alternative for securing food supply in both developing and developed nations. Recirculating aquaculture systems tend to be capital-intensive and require significant power to circulate the water in the fish tanks, which helps with the removal of waste and the distribution of oxygen. To reduce capital costs, alternative, culture vessels made from locally available materials were investigated (i.e. square-shaped tanks, and international bulk containers - IBC). These non-standard shaped culture tanks, pose an additional challenge for proper circulation of the water as compared to traditional round tanks. To address the issue of circulation, numerical and experimental data were obtained for rectangular containers. The numerical results were obtained using OpenFoam models of the experimental setup. The experimental data were obtained by measuring flow velocities in an IBC tank using Acoustic Doppler Velocimetry. Currently the experimental data show good repeatability when data are taken for at least five minutes at each position in the tank. The focus of the continuing work is to establish a good agreement between numerical and experimental results. Ultimately the study will contribute to the design of cost-effective recirculating aquaponic fish and plant systems which require lower capital expenditures and achieve energy-efficient circulation of water in the fish culture tanks.
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Maran, Audrey M. "Please pass the salt: The effect of sodium addition on insect contributions to nutrient cycling". W 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.114665.

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"Influence of nutrients addition for enhanced biogas production from energy crops: A Review". W 7th International Conference on Latest Trends in Engineering and Technology. International Institute of Engineers, 2015. http://dx.doi.org/10.15242/iie.e1115038.

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Radaza, Ivy Camille, John Francis Rizada, Mary Joyce Tan, Paul Jake Nalzaro i Terence Tumolva. "Modeling of Swelling and pH-Dependent Nutrient Release Kinetics of HPC/CMC/Alginate Hydrogel Blends for Agricultural Applications". W 7th GoGreen Summit 2021. Technoarete, 2021. http://dx.doi.org/10.36647/978-93-92106-02-6.6.

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The swelling and nutrient release behaviors of a novel hydrogel blend of hydroxypropyl cellulose (HPC), carboxymethyl cellulose (CMC), and sodium alginate (NaAlg) was investigated to determine its applicability as an agricultural soil conditioner. Hydrogel swelling and nutrient release data were obtained over time at varying temperatures and pH conditions. The experimental data were fit into the power law, Tsai and Strieder, and Johansson’s models to determine the kinetic parameters for the swelling behavior and nutrient release. Under the experimental swelling conditions, the maximum and minimum swelling capacities of the hydrogel blend were 322.9245% and 228.0483%, respectively. The data fit to the power law suggested that a pseudo Fickian behavior describes the diffusion mechanism. The data fit to the Tsai and Strieder and Johansson’s models provided the experimental values for the α and temperature correlation as 3.69×10-5 and 0.0278, respectively, which implies that the diffusion behavior within the hydrogel does not vary significantly within the temperature range. Lastly, the inconsistency observed in the nutrient release behaviors at varying pH suggested that additional trials may be required in order to establish a clearer relation between pH and nutrient release behavior.
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"The effect of additional subsurface drainage on water discharge and nutrient load on clay soil". W 2016 10th International Drainage Symposium. American Society of Agricultural and Biological Engineers, 2016. http://dx.doi.org/10.13031/ids.20162521381.

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Mirzaee Kakhki, Iman, Majid Charmchi i Hongwei Sun. "Computational Investigation of Gallium Nitrite Ammonothermal Crystal Growth". W ASME 2013 Heat Transfer Summer Conference collocated with the ASME 2013 7th International Conference on Energy Sustainability and the ASME 2013 11th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/ht2013-17506.

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This paper presents a rigorous approach to the simulation of the GaN growth process, which involves dissolution kinetics, transport by thermal convection and crystallization kinetics. So far, a wide range of numerical efforts have been published which provide valuable information on the flow field and temperature distribution in the hydrothermal crystal growth processes; however, no research has attempted to model the mass transfer in the nutrient porous basket nor did they present a modeling of the nutrient/mineralizers/solvent chemical reactions. In addition, the rate of crystallization was not numerically considered in the model. This paper shows the feasibility of developing a robust numerical code based on models that accurately account for the rate of nutrient dissolution and crystallization kinetics. Numerical simulation results revealed that chemical reaction kinetics can directly affect the crystallization rate and is a dominant factor in this phenomenon.
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Raporty organizacyjne na temat "Nutrient additions"

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Kelly, J. M. Dynamics of Litter Decomposition, Microbiota Populations, and Nutrient Movement Following Nitrogen and Phosphorus Additions to a Deciduous Forest Stand. Office of Scientific and Technical Information (OSTI), październik 2002. http://dx.doi.org/10.2172/814493.

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Holderman, Charlie. Characterization of the Kootenai River Aquatic Macroinvertebrate Community before and after Experimental Nutrient Addition, 2003-2006. [Chapter 3]. Office of Scientific and Technical Information (OSTI), luty 2009. http://dx.doi.org/10.2172/962198.

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Jones, Scott B., Shmuel P. Friedman i Gregory Communar. Novel streaming potential and thermal sensor techniques for monitoring water and nutrient fluxes in the vadose zone. United States Department of Agriculture, styczeń 2011. http://dx.doi.org/10.32747/2011.7597910.bard.

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The “Novel streaming potential (SP) and thermal sensor techniques for monitoring water and nutrient fluxes in the vadose zone” project ended Oct. 30, 2015, after an extension to complete travel and intellectual exchange of ideas and sensors. A significant component of this project was the development and testing of the Penta-needle Heat Pulse Probe (PHPP) in addition to testing of the streaming potential concept, both aimed at soil water flux determination. The PHPP was successfully completed and shown to provide soil water flux estimates down to 1 cm day⁻¹ with altered heat input and timing as well as use of larger heater needles. The PHPP was developed by Scott B. Jones at Utah State University with a plan to share sensors with Shmulik P. Friedman, the ARO collaborator. Delays in completion of the PHPP resulted in limited testing at USU and a late delivery of sensors (Sept. 2015) to Dr. Friedman. Two key aspects of the subsurface water flux sensor development that delayed the availability of the PHPP sensors were the addition of integrated electrical conductivity measurements (available in February 2015) and resolution of bugs in the microcontroller firmware (problems resolved in April 2015). Furthermore, testing of the streaming potential method with a wide variety of non-polarizable electrodes at both institutions was not successful as a practical measurement tool for water flux due to numerous sources of interference and the M.S. student in Israel terminated his program prematurely for personal reasons. In spite of these challenges, the project funded several undergraduate students building sensors and several master’s students and postdocs participating in theory and sensor development and testing. Four peer-reviewed journal articles have been published or submitted to date and six oral/poster presentations were also delivered by various authors associated with this project. We intend to continue testing the "new generation" PHPP probes at both USU and at the ARO resulting in several additional publications coming from this follow-on research. Furthermore, Jones is presently awaiting word on an internal grant application for commercialization of the PHPP at USU.
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Nikolaeva, N. A., P. P. Borisova, N. M. Alekseeva i E. S. Vasileva. The effect of energy-rich feed additives on nutrient digestibility of rations in young Simmental cattle breeds in Yakutia. ИД «Панорама», 2018. http://dx.doi.org/10.18411/120369.

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Uni, Zehava, i Peter Ferket. Enhancement of development of broilers and poults by in ovo feeding. United States Department of Agriculture, maj 2006. http://dx.doi.org/10.32747/2006.7695878.bard.

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The specific objectives of this research were the study of the physical and nutritional properties of the In Ovo Feeding (IOF) solution (i.e. theosmostic properties and the carbohydrate: protein ratio composition). Then, using the optimal solution for determining its effect on hatchability, early nutritional status and intestinal development of broilers and turkey during the last quarter of incubation through to 7 days post-hatch (i.e. pre-post hatch period) by using molecular, biochemical and histological tools. The objective for the last research phase was the determination of the effect of in ovo feeding on growth performance and economically valuable production traits of broiler and turkey flocks reared under practical commercial conditions. The few days before- and- after hatch is a critical period for the development and survival of commercial broilers and turkeys. During this period chicks make the metabolic and physiological transition from egg nutriture (i.e. yolk) to exogenous feed. Late-term embryos and hatchlings may suffer a low glycogen status, especially when oxygen availability to the embryo is limited by low egg conductance or poor incubator ventilation. Much of the glycogen reserve in the late-term chicken embryo is utilized for hatching. Subsequently, the chick must rebuild that glycogen reserve by gluconeogenesis from body protein (mostly from the breast muscle) to support post-hatch thermoregulation and survival until the chicks are able to consume and utilize dietary nutrients. Immediately post-hatch, the chick draws from its limited body reserves and undergoes rapid physical and functional development of the gastrointestinal tract (GIT) in order to digest feed and assimilate nutrients. Because the intestine is the nutrient primary supply organ, the sooner it achieves this functional capacity, the sooner the young bird can utilize dietary nutrients and efficiently grow at its genetic potential and resist infectious and metabolic disease. Feeding the embryo when they consume the amniotic fluid (IOF idea and method) showed accelerated enteric development and elevated capacity to digest nutrients. By injecting a feeding solution into the embryonic amnion, the embryo naturally consume supplemental nutrients orally before hatching. This stimulates intestinal development to start earlier as was exhibited by elevated gene expression of several functional genes (brush border enzymes an transporters , elvated surface area, elevated mucin production . Moreover, supplying supplemental nutrients at a critical developmental stage by this in ovo feeding technology improves the hatchling’s nutritional status. In comparison to controls, administration of 1 ml of in ovo feeding solution, containing dextrin, maltose, sucrose and amino acids, into the amnion of the broiler embryo increased dramatically total liver glycogen in broilers and in turkeys in the pre-hatch period. In addition, an elevated relative breast muscle size (% of broiler BW) was observed in IOF chicks to be 6.5% greater at hatch and 7 days post-hatch in comparison to controls. Experiment have shown that IOF broilers and turkeys increased hatchling weights by 3% to 7% (P<0.05) over non injected controls. These responses depend upon the strain, the breeder hen age and in ovo feed composition. The weight advantage observed during the first week after hatch was found to be sustained at least through 35 days of age. Currently, research is done in order to adopt the knowledge for commercial practice.
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Holderman, Charlie, ID] Bonners Ferry, Paul Anders, ID] Moscow, Bahman Shafii i WA] Clarkston. Characterization of the Kootenai River Algae Community and Primary Productivity Before and After Experimental Nutrient Addition, 2004?2007 [Chapter 2, Kootenai River Algal Community Characterization, 2009 KTOI REPORT]. Office of Scientific and Technical Information (OSTI), lipiec 2009. http://dx.doi.org/10.2172/962647.

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Dick, Warren, Yona Chen i Maurice Watson. Improving nutrient availability in alkaline coal combustion by-products amended with composted animal manures. United States Department of Agriculture, 2002. http://dx.doi.org/10.32747/2002.7587240.bard.

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Hypothesis and Objectives: We hypothesized that coal combustion products (CCPs), including those created during scrubbing of sulfur dioxide from flue gases, can be used alone or mixed with composted animal manures as effective growth media for plants. Our specific objectives were, therefore, to (1) measure the chemical, physical and hydraulic properties of source materials and prepared mixes, (2) determine the optimum design mix of CCPs and composted animal manures for growth of plants, (3) evaluate the leachate water quality and plant uptake of selected elements from prepared mixes, (4) quantify the interaction between composted animal manures and B concentrations in the mixes, (5) study the availability of P to plants growing in the mixes, and (6) determine the microbial community and siderophores involved in the solubilization of Fe and its transfer to plants. Background: In recent years a major expansion of electricity production by coal combustion has taken place in Israel, the United States and the rest of the world. As a result, a large amount of CCPs are created that include bottom ash, fly ash, flue gas desulfurization (FGD) gypsum and other combustion products. In Israel 100,000 tons of fly ash (10% of total CCPs) are produced each year and in the US a total of 123 million tons of CCPs are produced each year with 71 million tons of fly ash, 18 million tons of bottom ash and 12 million tons of FGD gypsum. Many new scrubbers are being installed and will come on-line in the next 2 to 10 years and this will greatly expand the amount of FGD gypsum. One of the main substrates used in Israel for growth media is volcanic ash (scoria; tuff). The resemblance of bottom coal ash to tuff led us to the assumption that it is possible to substitute tuff with bottom ash. Similarly, bottom ash and FGD gypsum were considered excellent materials for creating growth mixes for agricultural and nursery production uses. In the experiments conducted, bottom ash was studied in Israel and bottom ash, fly ash and FGD gypsum was studied in the US. Major Achievements: In the US, mixes were tested that combine bottom ash, organic amendments (i.e. composts) and FGD gypsum and the best mixes supported growth of tomato, wheat and marigolds that were equal to or better than two commercial mixes used as a positive control. Plants grown on bottom ash in Israel also performed very well and microelements and radionuclides analyses conducted on plants grown on bottom coal ash proved it is safe to ingest the edible organs of these plants. According to these findings, approval to use bottom coal ash for growing vegetables and fruits was issued by the Israeli Ministry of Health. Implications: Bottom coal ash is a suitable substitute for volcanic ash (scoria; tuff) obtained from the Golan Heights as a growth medium in Israel. Recycling of bottom coal ash is more environmentally sustainable than mining a nonrenewable resource. The use of mixes containing CCPs was shown feasible for growing plants in the United States and is now being evaluated at a commercial nursery where red sunset maple trees are being grown in a pot-in-pot production system. In addition, because of the large amount of FGD gypsum that will become available, its use for production of agronomic crops is being expanded due to success of this study.
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Dick, Warren, Yona Chen i Maurice Watson. Improving nutrient availability in alkaline coal combustion by-products amended with composted animal manures. United States Department of Agriculture, grudzień 2006. http://dx.doi.org/10.32747/2006.7695883.bard.

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Hypothesis and Objectives: We hypothesized that coal combustion products (CCPs), including those created during scrubbing of sulfur dioxide from flue gases, can be used alone or mixed with composted animal manures as effective growth media for plants. Our specific objectives were, therefore, to (1) measure the chemical, physical and hydraulic properties of source materials and prepared mixes, (2) determine the optimum design mix of CCPs and composted animal manures for growth of plants, (3) evaluate the leachate water quality and plant uptake of selected elements from prepared mixes, (4) quantify the interaction between composted animal manures and B concentrations in the mixes, (5) study the availability of P to plants growing in the mixes, and (6) determine the microbial community and siderophores involved in the solubilization of Fe and its transfer to plants. Background: In recent years a major expansion of electricity production by coal combustion has taken place in Israel, the United States and the rest of the world. As a result, a large amount of CCPs are created that include bottom ash, fly ash, flue gas desulfurization (FGD) gypsum and other combustion products. In Israel 100,000 tons of fly ash (10% of total CCPs) are produced each year and in the US a total of 123 million tons of CCPs are produced each year with 71 million tons of fly ash, 18 million tons of bottom ash and 12 million tons of FGD gypsum. Many new scrubbers are being installed and will come on-line in the next 2 to 10 years and this will greatly expand the amount of FGD gypsum. One of the main substrates used in Israel for growth media is volcanic ash (scoria; tuff). The resemblance of bottom coal ash to tuff led us to the assumption that it is possible to substitute tuff with bottom ash. Similarly, bottom ash and FGD gypsum were considered excellent materials for creating growth mixes for agricultural and nursery production uses. In the experiments conducted, bottom ash was studied in Israel and bottom ash, fly ash and FGD gypsum was studied in the US. Major Achievements: In the US, mixes were tested that combine bottom ash, organic amendments (i.e. composts) and FGD gypsum and the best mixes supported growth of tomato, wheat and marigolds that were equal to or better than two commercial mixes used as a positive control. Plants grown on bottom ash in Israel also performed very well and microelements and radionuclides analyses conducted on plants grown on bottom coal ash proved it is safe to ingest the edible organs of these plants. According to these findings, approval to use bottom coal ash for growing vegetables and fruits was issued by the Israeli Ministry of Health. Implications: Bottom coal ash is a suitable substitute for volcanic ash (scoria; tuff) obtained from the Golan Heights as a growth medium in Israel. Recycling of bottom coal ash is more environmentally sustainable than mining a nonrenewable resource. The use of mixes containing CCPs was shown feasible for growing plants in the United States and is now being evaluated at a commercial nursery where red sunset maple trees are being grown in a pot-in-pot production system. In addition, because of the large amount of FGD gypsum that will become available, its use for production of agronomic crops is being expanded due to success of this study.
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Borisova, P. P., N. A. Nikolaev i N. M. Alekseeva. INFLUENCE OF USE OF ENERGY SATURATED FODDER ADDITIVES IN DIETS ON DIGESTIBILITY OF NUTRIENTS TELECOMS IN THE AGE OF 22-23 MONTHS OF SIMMENTAL BREED IN CONDITIONS OF CENTRAL YAKUTIA. Ljournal, 2019. http://dx.doi.org/10.18411/2019-b-m-a-0529.

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Lers, Amnon, i Pamela J. Green. Analysis of Small RNAs Associated with Plant Senescence. United States Department of Agriculture, marzec 2013. http://dx.doi.org/10.32747/2013.7593393.bard.

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Senescence is an agriculturally significant process due to its negative impact to crop yield and postharvest quality. The genetic regulatory systems controlling senescence induction and progress respond to both developmental and environmental stress signals and involve numerous gene expression changes. Knowledge about the key molecular factors which control senescence is very limited. MicroRNAs (miRNAs) are a class of small RNAs which typically function by guiding cleavage of target messenger RNAs. They have been shown to play major roles in a variety of plant processes including development, responses to environmental stresses, and senescence. The long-term goal of this work is to elucidate roles of small RNAs associated with plant senescence. The hypothesis underlying this research is that miRNA-mediated regulation makes important contributions to the senescence process in plants. Specific, original research objectives included: 1) Profiling of small RNAs from senescing plants; 2) Data Analysis and public access via a user-friendly web interface; 3) Validation of senescence-associated miRNAs and target RNAs; 4) Development of transgenic plants for functional analysis of miRNAs in Arabidopsis. Major revisions made in the research compared to the original work plan included 1) Exclusion of the planned work with tomato as recommended by the BARD review panel; 2) Performing miRNA study also in senescing Arabidopsis siliques, in addition to senescing leaves. To identify senescenceregulation of miRNAs in Arabidopsis thaliana, eight small RNA libraries were constructed and sequenced at four different stages of development and senescence from both leaves and siliques, resulting in more than 200 million genome-matched sequences. Parallel Analysis of RNA Ends (PARE) libraries, which enable the large-scale examination of miRNA-guided cleavage products, were also constructed and sequenced, resulting in over 750 million genome-matched sequences. These massive datasets lead to the identification of new miRNAs, as well as new regulation of known miRNAs and their target genes during senescence, many of which have established roles in nutrient responsiveness and cell structural integrity. In keeping with remobilization of nutrients thought to occur during senescence, many miRNAs and targets had opposite expression pattern changes between leaf and silique tissues during the progression of senescence. Taken together, these findings highlight the integral role that miRNAs may play in the remobilization of resources and alteration of cellular structure that is known to occur in senescence. Experiments were initiated for functional analysis of specific senescence-associated miRNAs and respective target genes. Transgenic Arabidopsis plants were generated in which miR408, found in this study to be significantly induced in leaf senescence, was over-expressed either constitutively or under a senescence-specific promoter. These plants are currently being characterized for any altered phenotypes. In addition T-DNA knock out mutants for various target genes identified in this research are being analyzed. This work provides insights about specific miRNAs that contribute to leaf and silique senescence. The knowledge generated may suggest new strategies to monitor and alter the progression of senescence in crops for agricultural improvement.
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