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Biomass response of selected African leafy vegetables in pots to rate of application of three types of animal manure.Okorogbona, Alfred Oghode Misaiti. January 2011 (has links)
Thesis (MTech. degree in Agriculture)--Tshwane University of Technology, 2011.
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"Stinky and smelly - but profitable" : the Cape guano trade, c.1843 - 1910Snyders, Hendrik 12 1900 (has links)
Thesis (PhD)-- Stellenbosch University, 2011. / ENGLISH ABSTRACT: Soil infertility and concomitant low levels of food security under conditions of population pressure and land scarcity have been, and still remain, one of society’s most daunting challenges. Over time, societies have tried to maximize the yield from the available land through the use of various fertilisers. In the 19th century in the midst of an environment infertility crisis, guano (bird dung) from the Peruvian coastal islands became, through a combination of factors, the international fertilizer of choice for most commercial farmers. As a result, a combination of natural factors, monopoly control and price manipulation contributed to the relative scarcity of the product. Nevertheless, strategic manoeuvring between the major players prevented any significant change in the supply regime.
News of discoveries along the African coasts in the 1840s, some inside the territorial waters of the Cape Colony, introduced a new dimension to the trade. Both established merchant houses and new contenders strategised in an attempt to gain monopoly control. These events created new policy crises for the Cape Colony, the closest legal authority, and led to new policy and other initiatives in the absence of imperial precedents. The trade in guano also impacted on constitutional, political and scientific developments in the colony. Key amongst these was the struggle for monopoly control over both the Cape- and Ichaboe-based supply, which pitted individuals, family members and businesses against each other. The process became intertwined with political developments such as the transfer of political control from the Imperial authorities to the colonies. In addition, a coercive labour system developed under the colonial administration and colonial farmers struggled for fair access to the fertiliser, which added another dimension to the trade. / AFRIKAANSE OPSOMMING: Daar is ‘n noue verband tussen bevolkingsgetalle, oesopbrengs, voedselsekuriteiten die beskikbaarheid van voldoende bewerkbare landbougrond. Waar samelewings probleme ervaar met die gehalte van hul landbougrond, is daar heel dikwels ook lae vlakke van voedselsekuriteit en word daar gewoonlik ook ‘n onsekere van-die-hand-tot–die-mond bestaan gevoer. As ‘n teenvoeter vir hongersnood as gevolg van lae oesopbrengs, het uiteenlopende samelewings met verloop van tyd en na gelang van hulle natuurlike omstandighede, bepaalde bemestingstradisies ontwikkel in ‘n poging om ‘n volhoubare opbrengs te verseker.
Gedurende die 19de eeu, het ghwanobemesting te midde van ‘n wêreldwye grondgehalte krisis, ongekende gewildheid onder winsgedrewe landbouers bereik en voorts ook daarin geslaag om ander vorme van bemesting soos beenmeel en kraalmis as voorkeur produkte te vervang. As gevolg van ‘n kombinasie van natuurlike faktore, monopoliebeheer oor die eiland-gebaseerde ghwanobron en prysmanipulasie, was die produk wataanvanklik net vanaf Peru in Suid Amerika ingevoer is, dus nie vrylik beskikbaar nie en moes belangstellende boere hoë pryse daarvoor betaal. Vanselfsprekend het dit tot groot frustrasie en ontsteltenis in die geledere van diegene wat ‘n belegging in kommersiële landbou wou maak, gelei. Die onderlinge politieke intriges, knoeiery en pogings van plaaslike en oorsese sakemanne om mekaar te uitoorlê in die soeke na alleenbeheer oor die beskikbare ghwanobronne, het sake nie juis verbeter nie. Inteendeel, die situasie het net vererger toe alternatiewe ghwano bronne langs die wes- en ooskus van Afrika sowel as op ‘n reeks ander eilande in die Atlantiese Oseaan ontdek is.
Die ontdekking van ghwano binne die Kaapse gebeidswaters in die 19de eeu, het die owerhede met ’n beleidsdilemma waarvoor daar nie enige presedente in die Britse Ryk bestaan het nie gelaat. Daarbenewens was die kolonie te midde van heelparty konstitusionele en ander kwessies en het die toevoeging van die ghwanohandel die maatskaplike en politieke lewe van die kolonie wesenlik beïnvloed.
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The effects of irrigation and nitrogen on productivity, marketable yield and [supercript 1]H-NMR based metabolic profiling of African nightshade (Solanum retroflexum)Masemola, Makhutse Clive 09 1900 (has links)
Efficient agronomic practices are vital for achieving sustainable management of water
resources and N for producing highly nutritious leafy vegetables to curb malnutrition and
poverty. The importance of proper N and irrigation of sustainable crop production is well
recognised in literature, although irrigation and N application rate guidelines for ALV’s
might not be sufficient for advisory purposes, especially for smallholder and commercial
farmers. The limited access is attributed by factors such as the lack of commercialisation as a
result of limited agronomic information describing optimum management options for S.
retroflexum. Availability of such information would contribute to successful
commercialisation of this crop. The primary objective of this study was to establish optimum
agronomic management practices for S. retroflexum for smallholder farmer as well as
commercial production in South Africa.
This project consists of three main components with the overall objective to evaluate
agronomic management practices of irrigation and N application on the marketable yield,
nutritional water productivity and 1H-NMR metabolic profiling under a rainshelter. The
results suggested that S. retroflexum responded positively to N application rates until an
optimum marketable yield was obtained at 150 kg N·ha-1 with I66%FC, followed by the
I100%FC with 150 kg N·ha-1,while, the lowest biomass was recorded in the I33%FC
irrespective of the N application rate. This also indicates of how S. retroflexum is affected by
insufficient irrigation, even at sufficient N application rates. N and irrigation are key factors
limiting plant survival and growth and low applications has adverse effects on the marketable
yield of S. retroflexum. Dry matter production increased with the higher N application and a
linear increase was observed with N application having a significant effect on the dry matter
production.
Maximum irrigation use efficiency (IUE), was obtained in the moderately irrigated treatment
(I66%FC) and the 150 kg N·ha-1, followed by the I100%FC and 150 kg N·ha-1. The stressed irrigation and N treatments showed sustainably low irrigation use efficiency as compared to
the well irrigated treatment. This suggests the competitive capacity of S. retroflexum roots to
draw water from deeper parts of the soil profile, during stressed conditions to maintain the
turgor pressure, indicating that production of S. retroflexum is possible in arid areas where water could be a limiting input, but might not be profitable for farmers. However, the
biomass yields obtained under the less irrigated soil water conditions may lack the quality
needed to market the produce.
The NWP for Zn and Fe showed significant differences among the irrigation and N
treatments. Although the NWP of Mg in S. retroflexum was neither influenced by irrigation
nor N application, with no statistical differences between the irrigation and N application
observed. Among the different irrigation and N treatments evaluated, I33%FC obtained the
lowest NWP irrespective of the N application rate, followed by I100%FC. The NWP
increased linearly with an increase in N application. Optimum Fe NWP was obtained with
150 kg N ha-1, but declined significantly at application 225 kg N ha-1 in I33%FC and
I100%FC. Maximum Fe NWP was obtained with I66%FC with 150 kg N ha-1. The NWP Fe
for S. retroflexum in this study, are acceptable when compared to those obtained in literature.
Therefore a significant interaction between N and irrigation application exist, with respect to
Fe and Zn availability of S. retroflexum, which could be ideal for Fe and Zn malnutrition
alleviation in resource poor households.
1H-NMR based metabolomic profiling was utilized for compound annotation as effected by
irrigation and N. Chlorogenic acid, proline, sucrose and trigonelline were associated with
separation in the irrigation treatments. Since no separation of the irrigation or N treatments
was observed with the PCA, an OPLS-DA plot was constructed. A pairwise comparison of
the I33%FC and I100%FC samples was done, which provided better separation between the
clusters for the first harvest. Even better separations were observed with a pairwise OPLSDA
analysis of the I33%FC and I100%FC samples for the second harvest. Primary
metabolites such as sucrose, and proline and secondary metabolites trigonelline and
chlorogenic acid were responsible for grouping of the stressed irrigation treatment as
compared to the well irrigated treatment. Main findings of the study suggest that S. retroflexum is highly nutritious in Fe, Zn and Mg, which might play a significant role in
malnutrition alleviation. Solanum retroflexum requires sufficient soil water content, for
achieving high nutrient yield and nutritional water productivity.
The results clearly illustrate that the perception that S. retroflexum grow well on low soil
fertility mostly practised in rural and smallholder farming is incorrect and misleading.
Moreover, S. retroflexum can be an ideal cropping system for smallholder and commercial
farmers in water scarce areas such as South Africa, although marketable yield is severely
affected. / Agriculture and Animal Health / M. Sc. (Agriculture)
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Chemical composition of baby spinach (Spinacia oleracea L.) as affected by nitrogen, phosphorous and potassium nutritionZikalala, Bongekile Octavia 11 1900 (has links)
Baby spinach (Spinacia oleracea L.) is considered to be the one of the extremely nutritious vegetables, rich both in phytochemicals and core nutrients. Nowadays, phytochemicals in plants are raising interest in consumers for their roles in the maintenance of human health. Variation in content of bioactive compounds and core nutrients is the main concern in vegetable production. Factors such as cultural practices specially fertilization, may affect the nutritional and medicinal properties of the plants
Therefore, three parallel trials for NPK to investigate the response of baby spinach leaves to nitrogen (N), phosphorus (P) and potassium (K) on chemical composition were conducted, with treatments arranged as follows: 0, 45, 75, 105, 120 kg·ha-1 N and P and 0, 60, 85, 106, 127, 148 kg·ha-1 K in a randomized complete block design (RCBD) with four replications. The results demonstrated that, application of nitrogenous, phosphorus, potassium fertilizers significantly increased the total phenolic content, total antioxidant activity, total flavonoid content and vitamin C while magnesium, iron, zinc and selenium did not exhibit significant response to all treatments applied. The increase in concentrations on total phenolic content, total antioxidant activity, total flavonoid content and vitamin C was observed, reaching maximum at 45 kg·ha-1 N, 75 kg·ha-1 P and 85 kg·ha-1 K. The optimum rates of 45 kg·ha-1 N, 75 kg·ha-1 P, 85 kg·ha−1 K were then used to formulate the NPK treatment combinations as follows: 0, 30: 30: 40, 45:45:60, 60:60:70, 75:75:90 kg·ha-1, arranged in a RCBD with three replicates. The results showed that total phenolic content, total antioxidant activity , total flavonoid content and vitamin C reached maximum in baby spinach leaves at N45:P45:K60 kg·ha-1. / Agriculture and Animal Health / M. Sc. (Agriculture)
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Chemical composition of baby spinach (Spinacia oleracea L.) as affected by nitrogen, phosphorous and potassium nutritionZikalala, Bongekile Octavia 11 1900 (has links)
Baby spinach (Spinacia oleracea L.) is considered to be the one of the extremely nutritious vegetables, rich both in phytochemicals and core nutrients. Nowadays, phytochemicals in plants are raising interest in consumers for their roles in the maintenance of human health. Variation in content of bioactive compounds and core nutrients is the main concern in vegetable production. Factors such as cultural practices specially fertilization, may affect the nutritional and medicinal properties of the plants
Therefore, three parallel trials for NPK to investigate the response of baby spinach leaves to nitrogen (N), phosphorus (P) and potassium (K) on chemical composition were conducted, with treatments arranged as follows: 0, 45, 75, 105, 120 kg·ha-1 N and P and 0, 60, 85, 106, 127, 148 kg·ha-1 K in a randomized complete block design (RCBD) with four replications. The results demonstrated that, application of nitrogenous, phosphorus, potassium fertilizers significantly increased the total phenolic content, total antioxidant activity, total flavonoid content and vitamin C while magnesium, iron, zinc and selenium did not exhibit significant response to all treatments applied. The increase in concentrations on total phenolic content, total antioxidant activity, total flavonoid content and vitamin C was observed, reaching maximum at 45 kg·ha-1 N, 75 kg·ha-1 P and 85 kg·ha-1 K. The optimum rates of 45 kg·ha-1 N, 75 kg·ha-1 P, 85 kg·ha−1 K were then used to formulate the NPK treatment combinations as follows: 0, 30: 30: 40, 45:45:60, 60:60:70, 75:75:90 kg·ha-1, arranged in a RCBD with three replicates. The results showed that total phenolic content, total antioxidant activity , total flavonoid content and vitamin C reached maximum in baby spinach leaves at N45:P45:K60 kg·ha-1. / Agriculture and Animal Health / M. Sc. (Agriculture)
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Organic manure effects on selected soil properties, water use efficiency and grain yield of sunflowerMokgolo, Matome Josphinos January 2016 (has links)
MSCAGR (Soil Science) / Department of Soil Science / The application of organic manures as alternatives to reduce the use of mineral fertilizers is
considered a good agricultural practice for smallholder farmers. However, the effect of organic
manure on soil properties and crop yield depends upon its application rate and chemical
composition. Climatic seasonal variability within the study area could adversely affect crop
production. The amount of rainfall and temperature are among the most important factors that
determines crop production. This field experiment was carried out during the 2013/2014 and
2014/2015 cropping seasons at the University of Venda experimental farm which is located
about 2 km west of Thohoyandou town in the Vhembe District, Limpopo Province.
The main objective of this study was to determine the effect of three types of organic manure
(cattle, poultry and their combination (1:1)) on yield and water use efficiency of sunflower
(Helianthus annuus L.) and selected soil physical and chemical properties under rainfed
conditions. The experiment was a randomized complete block design (RCBD) with four
treatments and four replications (control (C0), cattle manure (CM), poultry manure (PM) and
their combination (CM + PM)). All organic manures were applied 21 days before planting at a
rate equivalent to 20 t ha-1. The manures were incorporated in the soil using a hoe to an
approximate depth of 10 cm.
Crop water use (WU) and water use efficiency (WUE) were determined using the water balance
equation. Rainfall was measured using three standard rain gauges installed on the experimental
site. Change in soil moisture storage was determined by monitoring soil moisture content
weekly using a neutron water meter (NWM), calibrated on the experimental site.
Data on sunflower dry matter and leaf area index (LAI) was collected at flower bud stage,
flowering stage and at grain maturity stage. Plant height and stem girth were also determined at
the same developmental stages. Grain yield was measured at physiological maturity.
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Analysis of variance (ANOVA) was carried out using SPSS software. Due to seasonal variability
encountered during the two cropping seasons, particularly in terms of rainfall, further analysis of
two factors (viz. cropping season and organic manure) and their interaction were performed.
The differences between treatment means were separated using the least significant differences
(LSD) procedure.
The results showed that organic manure application had no significant effect on soil physical
properties. Poultry manure application resulted in lowest bulk density (BD) with a decrease of
32% in the top layer (0 – 20 cm) compared to control. Cattle manure + PM and CM application
decreased BD in the top layer by 14% and 9% compared to control, respectively. Poultry
manure and CM recorded almost the highest similar stable aggregate fractions at all soil depths.
Poultry manure recorded the highest final infiltration rate and cumulative infiltration followed by
CM and CM + PM. The control treatment retained the highest mean water content compared to
other treatments at both field capacity (FC) and wilting point (WP). Cattle manure + PM and PM
recorded the least mean water content among others at FC and WP respectively. This could be
as a result of increased micropores by organic manure application on a clayey soil which
allowed an ease movement of water that control treatment which had no manure application.
Total N, Ca, and Zn were significantly different between treatments in the first cropping season
while K, Na, CEC and Zn were significantly different in second cropping season. pH recorded no
significant difference in all treatments in both cropping seasons. CM + PM recorded the highest
OC at top layer (0 – 20 cm) in both cropping seasons compared to other treatments.
Dry matter yield and LAI at flower bud, flowering and maturity stages increased with the
application of different manures compared to the C0. Organic manure application showed a
significant (p<0.05) effect on dry matter at all growth stages in the second cropping season.
Organic manure had a significant effect on LAI only at flower bud stage of the first cropping
season, with PM and CM + PM recording the highest similar value of 1.31. The manure
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application also showed a significant (P<0.05) effect on plant height and stem girth at all
growing stages in the second cropping season, whereas in the first cropping season the
significant effect was only in the flower bud stage for both parameters.
Grain yield was significantly affected by the manure application in the second cropping season.
Manure application in the second cropping season resulted in an increase in the grain yield
compared to the first cropping season, except for PM where the grain yield decreased
significantly by 167.92% from the first cropping season. Then high grain yield in the second
cropping season could be as a result of high WUE reported.
The manure application had a significant effect (p<0.05) on water use efficiency (WUE) in the
second cropping season. The WUE recorded the highest values under CM and CM + PM
treatments in second cropping season than in first cropping season, while PM recorded the
highest WUE value in the first cropping season. Generally, organic manures used obtained
higher grain yield and WUE compared to control.
Keywords: Organic manure, smallholder farmers, sunflower and water use efficiency
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The response of maize to selected ratios of organic fertilizers mixed with inorganic fertilizers in Ndlambe Local Municipality, Eastern Cape, South AfricaSolontsi, Mhlangabezi January 2013 (has links)
The majority of small-scale farmers in the Eastern Cape apply inadequate quantities of manure, inorganic (NPK) fertilizer and Gromor as lone fertilizers or tend to mix manure or Gromor with chemical fertilizers for crops, without any scientific basis (Mkile, 2001). Hence this study – aimed at achieving effective and efficient use of chemical fertilizers, manure and Gromor, either as lone fertilizers or mixed with one another, in maize production – was established. A three-year dry land field experiment, arranged in a RCBD with 3 replicates where cattle manure, chemical fertilizer and Gromor were mixed at different ratios – as treatments FM1 (10 percent fertilizer + 90 percent manure); FM2 (25 percent fertilizer + 75 percent manure); FM3 (50 percent fertilizer + 50 percent manure); MAP (100 percent fertilizer); M (100 percent cattle manure); FG1 (10 percent fertilizer + 90 percent Gromor); FG2 (25 percent fertilizer + 75 percent Gromor); FG3 (50 percent fertilizer + 50 percent Gromor); G (100 percent Gromor) and a control (with nothing applied) – was conducted at the Nolukhanyo agricultural project at Bathurst in the Ndlambe Local Municipality. Maize cultivars PAN 6480 and Sahara were used as test crops. Manure, Gromor and soil were analyzed for their nutrient composition. Data recorded involving number of kernels per cob-1, grain and dry matter (DM) yields for the 2010-11, 2011-12 and 2012-13 seasons, and leaf area index (LAI) – were subjected to Genstat Version 14.1 for statistical analysis. Grain yields of PAN 6480 and Sahara recorded in seasons 2010-11, 2011-12 and 2012-13 were significantly higher (p≤0.05) than those of the controls. In 2012-13, PAN 6480 on treatments FG3 and FG1 produced the highest grain yields (5 327 and 5 107kg ha-1) respectively, while in 2010-11 the highest yield was 3 780kg ha-1. In the 2012-13 season, Sahara on F treatment was the highest with 4 553kg ha-1 whilst there were no significant differences in F and M treatments. Dry matter yields of Sahara were higher than those of PAN 6480 in all seasons. The highest Sahara LAI obtained on FM2 was 5.85 in the 2012-13 season, whereas PAN 6480 had LAI of 4.77 on F treatment, followed by FG3 with 4.72 LAI. PAN 6480 number of leaves for 6 plants in m2 and LAI in week 8 of the 2012-13 season had a positive correlation, r2=0.84. PAN 6480 number of kernels and cob length in the same area correlated quite well (r2 =0.91). Chemical fertilizer corrects the imbalances of nutrients inherent in organic manures and increases both maize grain yields and dry matter yields, and also influences number of leaves and LAI. Treatments FG1, FG3 and FM1 of PAN 6480 resulted in high maize grain yields when planted 13 in late November of the 2012-13 growing season and when water in the soil profile was conserved as a result of good rains received prior to planting. Treatments FG1 (10 percent fertilizer + 90 percent Gromor), FG3 (50 percent fertilizer + 50 percent Gromor) of PAN 6480 produced the highest grain yields (5 107kg ha-1 and 5 327kg ha-1 respectively) in the 2012-13 season, whilst FM1 (10 percent fertilizer + 90 percent manure) gave the highest grain yield (of 4 277kg ha-1) for the same cultivar in the 2010-11 season.
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Analysis of technical efficiency of small-scale maize producers: a case study in Tsolo magisterial district in O.R Tambo district in the Eastern Cape of South AfricaAvuletey, Richard January 2014 (has links)
Maize is the most important cereal crop grown in South Africa. This crop is produced throughout the country under diverse conditions and in diverse environments. The study only focuses on technical efficiency because it is an important subject in developing agriculture where resources are limited, but high population growth is very common. In such a setting, increased output will depend more on efficiency improvements and assessing the scope for such efficiency improvements within the system is a crucial need. The objective of the study was to determine the level of technical efficiency and to identify the socio-economic and institutional characteristics as well as the entrepreneurial spirit that influence the technical efficiency of small-scale maize producers in the Tsolo magisterial district. Purposive and Snowball sampling techniques were used to collect primary data from 120 small-scale farmers. The stochastic frontier model was used to determine the level of technical efficiency. The Multivariate OLS was used to analyze the socio-economic factors and institutional characteristics that have influenced the technical efficiency of maize production. A similar linear regression model was used to estimate the influence of positive psychological capital and entrepreneurial spirit on the technical efficiency of maize production. The stochastic results revealed that small-scale farmers in Tsolo are technically efficient at 98 percent in maize production and experience increasing return to scale (1.37), which means that increase in the use of inputs, will as well increase their productivity and efficiency. The inefficiency model results indicated that age, years in farming, household size and extension contact significant and 3 variables, namely, as years in farming, extension contact and farm size are significant in the OLS model. Lastly the results of the linear regression indicated that, out of the 4 variables estimated in the entrepreneurial spirit, self-efficacy and resilience were significant with respect to its responsiveness to total maize output.
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Oxidative ammonolysis of technical lignins and lignitesTyhoda, Luvuyo January 2003 (has links)
Thesis (MSc)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: Today there is renewed interest in using soil improvers with fertilising capability as
the use of inorganic fertilisers results in ground water pollution through leaching and
formation of nitrates in plant materials. Lignin is an important precursor of humic
material in soils and with modification, can be used as a raw material for producing
slow release nitrogenous fertilisers. This project focussed on the use of industrial
residues such as technical lignins which are produced by the South African pulping
industry as well as low grade coals such as lignite occurring in South Africa, for the
production of high-grade humic substances like Novihum TM, using the special
technology developed by the Institute of Plant and Wood Chemistry of the Technical
University of Dresden in Germany. Technicallignins derived from kraft lignin, sugar
cane baggase, autohydrolysis lignin with a trade name Sucrolin, a calcium
lignosulphonate and South African lignites mined in the Kraaifontein and BraekenfeIl
areas as well as German brown coal were subjected to oxidative ammonolysis with
the aim to produce slow release nitrogenous fertilizers.
Curie Point Pyrolysis GCIMS was used to determine the structural composition of the
raw materials and products. Oxidative ammonolysis reactions were carried out on a
laboratory and a pilot plant scale. Highest nitrogen contents were obtained with
Sucrolin lignin followed by the lignite from Germany. The amount of nitrogen that
could be fixed with oxidative ammonolysis varied between 1.44 - 10% for the various
raw materials. The CIN ratios obtained were in the range between 5 - 34. Marginal
differences were observed between the materials modified on lab and pilot plant
scales. There were improvements in the total incorporated nitrogen when the raw
materials were pre-activated with oxidising agents such as hydrogen perxide and a
fungal species, Phanaerochateae chrysosporium prior to oxidative ammonolysis.
Variable amounts of differently bonded nitrogen forms were obtained for the
materials tested due to their structural differences. / AFRIKAANSE OPSOMMING: Daar is deesdae hernude belangstelling in die gebruik van grondverbeteringsmiddels wat
ook 'n bemestingsfunksie het, aangesien die gebruik van anorganiese kunsmis
besoedeling van grondwater deur uitlogingen insypeling veroorsaak, wat weer tot die
vorming van nitrate in plantmateriaallei. Lignien is 'n belangrike voorloper van humiese
materiale in grondstowwe en kan dmv modifisering gebruik word as 'n grondstof vir die
produksie van stadigstikstof vrystellende nitro gene kunsmisstowwe. Die huidige projek
het gefokus op die gebruik van industriële residue en tegniese ligniene wat deur die Suid-
Afrikaanse pulpnywerheid geproduseer word, sowel as lae-graad steenkool soos ligniet
wat in Suid-Afrika aangetrefword, vir die produksie van hoë-graad humiese stowwe soos
Novihum TM. Hierdie produk is mbv spesiale tegnologie deur die Instituut van Plant- en
Houtchemie van die Tegniese Universiteit van Dresden in Duitsland ontwikkel.
In hierdie ondersoek is verskeie Suid-Afrikaanse tegniese ligniene soos Kraft lignien,
suikerriet bagasse, 'n outohidrolise lignien met die naam van Sucrolin en 'n
kalsiumlignosulfonaat sowel as SA ligniete, afkomstig van Brackenfell en Kraaifontein,
gebied en Duitse bruinkool, aan oksidatiewe ammonolise onderwerp om sodoende
verskillende, stadigvrstellende, stikstofryke kunsmisstowwe te vervaardig.
Curie Punt Pirolise GC/MS is gebruik om die chemiese struktuur van die grondstowwe
en produkte vas te stel. Oksidatiewe ammonolise reaksies is op 'n laboratorium en
loodsaanlegskaal. uitgevoer. Die hoogste stikstofinhoud is met Sucrolin lignien verkry,
gevolg deur die ligniet van Duitsland. Die hoeveelheid stikstof wat dmv oksidatiewe
ammonlise bereik kon word, het tussen 1.44 en 10% gewissel. Die CIN verhoudings wat
verkry was, het varieer tussen 5 en 34. Marginale verskille is tussen laboratorium - en
loodsaanlegsskaal gemodifiseerde grondstowwe waargeneem. Daar was verhogings in
stikstofinhoud wanneer die grondstowwe vooraf met oksiderende middels soos
waterstofperoksied of swamkultur soos Phanaerochatae chrysosporium, aktiveer is.
Stikstof is op verskillende maniere en in verskillende hoeveelhede gebind.
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Applications of dairy wastewater as a fertilizer to agricultural land : an environmental management perspectiveTorr, Leigh Christine 03 1900 (has links)
Thesis (MSc (Geography and Environmental Studies))--University of Stellenbosch, 2009. / As with any form of intensive agriculture, there are potential environmental impacts
associated with the management and housing of livestock on dairy farms. Within the
field of dairy farming, particular focus falls to the issue of environmental degradation
of water resources, as this form of pollution is currently a major environmental issue
around the world. Conventional agricultural practices involving the application of
chemical fertilizers to land and crops are causing environmental problems as a result of
poor management practices. Dairy wastewater and manures could however be a
valuable resource for agricultural producers in the form of an alternate fertilizer for
their crops. Waste application as a fertilizer is more environmentally friendly than
chemical fertilizers, and could drastically reduce costs for farmers, whilst alleviating
storage and management problems often associated with farmyard manures (FYM).
The application of organic wastes, notably livestock manures, to land has historically
been important for maintaining soil fertility on farms in terms of nutrient status and
organic matter levels, as well as helping to reduce soil erosion and improve waterholding
capacity. The research sought to investigate the environmental and economical
feasibility of using dairy wastewater and manures as an alternative form of fertilizer
within agriculture in South Africa.
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