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Die effek van verskillende oppervlakbewerkingspraktyke op die wortelverspreiding van wingerdBrink, Daan 03 1900 (has links)
Thesis (MScAgric (Soil Science))--University of Stellenbosch, 2007. / This study forms part of an ARC Nietvoorbij research project on the long-term effect of
different groundcover management practices in vineyards. This study concentrated on the
root distribution of the vines after different groundcover practices were used for one
decade.
The vineyard on the research farm of the Agricultural Research Council at Robertson,
South Africa, was divided into 56 equally distributed trail blocks, 14 treatments with four
replicas each. For the study Chardonnay cultivar on 99 Richter rootstock was used. This
study concentrated on only eight treatments. The eight different cover crop practices
consisted of the mechanical treatment, chemical treatment, straw mulch treatment,
permanent cover crop treatment and four annual cover crop treatments. The annual cover
crop treatments consisted of triticale cover crop that was sprayed with an herbicide before
bloom, a triticale cover crop that was left to die naturally, a grazing vetch cover crop that
was sprayed with an herbicide before bloom and a grazing vetch cover crop that was left
to die naturally. The vineyard was established in November 1992 while the different
treatments started in April 1993. Root studies were conducted during the 2002/2003
season.
In this study the auger method was used to determine root density (mm/cm³). The root
density was correlated with data from the penetrometer studies, yield and shoot mass
collected during the same season.
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An investigation into the influence of soil pattern on preferential flow and groundwater recharge in fractured bedrock and cover sand aquifersStander, McLachlan Du Toit 12 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Increased pressure on groundwater sources due to increased population size and threats of climate change is driving research to better understand the process of aquifer recharge. Soil pattern is of interest as it serves to partition rainwater into different flowpaths destined for surface runoff, evapotranspiration and deep percolation. The challenges inherent to studying these flowpaths are almost universal as uncertainties concerning spatial and temporal heterogeneity in catchments make the upscaling of models complex.
This research addresses these challenges as it aims to improve the catchment scale hydrological models of two aquifer systems: One a fractured bedrock system at the Kogelberg Nature Reserve, Kleinmond, and the other a cover sand system in Riverlands Nature Reserve, Malmesbury. This study focussed on strengthening the link between what is known about a given soil form and the hydrological assumptions that can be drawn from that classification, and formulating the results so that they may ultimately be used to calibrate the recharge prediction models for the respective catchments.
The research was done in two parts: The first phase was to conduct soil surveys in both reserves during which soils were classified according to South African Soil Classification. Samples were collected at representative observation points which provided textural data for use in pedotransfer functions (PTFs). These PTFs were used to estimate plant available water (PAW) and hydraulic conductivity (K) for the observed profiles. Infiltration experiments were subsequently done to investigate the infiltration patterns of distinctly different soil forms at two sites from each reserve. The experiments included double ring and mini disc infiltration, volumetric water content determination and flow path visualisation using a staining dye.
A statistical comparison between the hydrological properties (K and PAW) of the different soil forms suggest that hydraulic properties differed between the deep sandy soil forms (Fernwood, Pinegrove and Witfontein in Kogelberg and Witfontein, Concordia and Lamotte in Riverlands) and the shallow rocky soil forms (Cartref and Glenrosa in Kogelberg). Thus grouping of hydrological similar units (HSUs) could be done on the basis of the soil forms present within the given catchments.
The infiltration study showed that shallow, rocky soils that grade into bedrock would have infiltration rates far greater than those estimated using PTFs in Kogelberg. This is due to the prevalence of continuous preferential flow (PF) of water between coarse fragments in these profiles. Recharge estimates would thus be inaccurate in such soils and calibration using locally derived data is recommended.
On the contrary, PTFs produced accurate infiltration estimates relative to measured infiltration rates in deep sandy soils in Kogelberg and Riverlands. The Lamotte soil form is an example of such a soil form. It should however be noted that an increase in PF in these soils had subsequently higher K values than estimated, thus illustrating the link between PF and accelerated infiltration rates.
These results confirm that using soil survey information, in the form of a soil map, and calibrated hydrological properties, one can delineate HSUs that encompass a large degree of heterogeneity in a given catchment. / AFRIKAANSE OPSOMMING: Verhoogde druk op grondwaterhulpbronne weens die groeiende bevolking en klimaatsverandering dryf tans navorsing om akwifeer hervulling beter te verstaan. Die grondlaag is van belang sienend dat dit reënwater verdeel in oppervlak afloop, evapotranspirasie en diep dreinering. Die uitdagings in hidrologiese navorsing is universeel as gevolg van onsekerhede oor ruimtelike en tydelike variasie wat lei tot komplekse grondwatermodelle.
Diè navorsing mik om die tekortkominge in akwifeer hervulling aan te vul deur groundwatermodelle van twee akwifeersisteme te verbeter: Die een is 'n gebroke rots sisteem in die Kogelberg Natuur Reservaat, Kleinmond, en die ander is 'n sand-bedekde sisteem in Riverlands Natuur Reservaat, Malmesbury. Die navorsing streef om die verhouding tussen 'n spesifieke grondvorm en sy hidroliese vloeipaaie te bestudeer en om die gevolgtrekkings so te formuleer dat dit kan gebruik word om die onderskeie grondwatermodelle te kalibreer.
Die eerste fase van die navorsing was om 'n grondopname van die onderskeie reservate te doen waartydens die gronde geklassifiseer was volgens die Suid Afrikaanse Grondklassifikasie Sisteem. Grondmonsters is by verteenwoordigende observasiepunte geneem en geanaliseer om tekstuurdata vir pedo-oordraagbare-funksies (PTFs) te kry. Die PTFs was gebruik om plant beskikbare water (PBW) en hidrouliese geleiding (K) te voorspel vir die verskeie observasiepunte. Infiltrasie eksperimente was daarna gedoen om die infiltrasie patroon van twee verskillende grondvorms van elke reservaat te bestudeer. Die eksperimente sluit dubbel- en minidisk-infiltrasie, volumetriese waterinhoud bepaling en vloeipad visualisering met die gebruik van 'n kleurstof in.
Die statistiese vergelyking van die hidrouliese eienskappe (K en PBW) en grondvorm dui aan dat die hidrouliese eienskappe verskil tussen die diep, grondvorms met 'n oorwegende sand tekstuur (Fernwood, Pinegrove en Witfontein in Kogelberg en Witfontein, Concordia en Lamotte in Riverlands) en die vlakker, klipperige grondvorms (Cartref en Glenrosa in Kogelberg). Groepering van hidrologies soortgelyke eenhede (HSE's) kan dus op die basis van die teenwoordige grondvorms in 'n opvangsgebied gedoen word.
Die infiltrasie studie het bewys dat vlak, klipperige gronde wat tot die rotsbodem gradueer 'n baie hoër infiltratsie tempo sal hê as die PTF voorspelde waardes. Dit is as gevolg van die voorkoms van aaneenlopende voorkeurvloei (VV) van water tussen die growwe materiaal in die profiele, veral die gebroke rots ondergorond. Voorspellings van akwifeer hervulling sal dus onakkuraat wees en kalibrasie met plaaslike data word dus aanbeveel.
In teendeel met die begenoemde, het die PTFs akkurate voorspellings gemaak relatief tot die gemete infiltrasie tempo's in die diep sanderige grondvorms in Kogelberg en Riverlands. Dit was duidelik met metings dat 'n toename in aaneenlopende VV hoër gemete K waardes getoon as die voorspelde waardes. Die verband tussen VV en verhoogde infiltrasie tempo word dus hiermee geillustreer.
Die resultate bevestig dus dat grondopname data, in die vorm van 'n grondkaart en gekalibreerde hidrouliese eienskappe gebruik kan word om hidrologies soortgelyke eenhede uiteen te sit wat die meerderheid van die variasie in 'n gegewe opvangsgebied insluit. Die HSE's kan gebruik word om grondwatermodelle meer akkuraat te laat funksioneer en dus beter voorspellings te genereer.
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An evaluation of the effectiveness of coal ash as an amendment for acid soilsMbakwe, Ikenna 12 1900 (has links)
Thesis (MScAgric (Soil Science))--Stellenbosch University, 2005. / Soil acidity is one of the greatest limitations to crop production in most soils of the
world. The increasing high costs of conventional liming materials have made it
necessary to explore the possibilities of using cheaper substitutes. In South Africa, 16
million hectares of land are naturally acid while on the other hand, the country’s coalfired
power plants generate 28 million tons of mostly alkaline coal ash per year,
disposal of which is increasingly becoming difficult. The use of coal ash as an
agricultural soil amendment while solving the liming needs of local farmers, may also
present a safe and more economical disposal option. This study was carried out to
evaluate the effectiveness of coal ash as an agricultural liming material. A greenhouse
experiment was conducted using maize as test crop. A field experiment was also
established on Beestepan Farm in Middelburg, Mpumalanga Province using dry beans
as test crop for the first season. In both experiments, fresh unweathered coal ash from
Duvha power station (CCE 10%), dolomitic lime (CCE 77%) and calmasil (calcium
silicate slag, CCE 99%) were applied to acidic sandy loam soils in the presence or
absence of gypsum. Both calmasil and dolomitic lime were applied at equivalent rates
of 0, 1, 2, and 4 tons/ha, and rates of 0, 7, 14 and 28 tons/ha were used for ash.
Gypsum was applied at a rate of 4 tons/ha. All treatments were applied in three
replications. Results showed that liming increased soil pH, improved soil nutrient
status and plant uptake of base cations, and enhanced yield. In the greenhouse, coal
ash decreased exchangeable acidity from 13.0 mmolc/kg to 6.67 mmolc/kg, increased
Ca levels from 200 mg/kg to 379 mg/kg, and increased Mg levels from 25.9 mg/kg to
42.0 mg/kg. Nitrate levels were also raised from 4.4 mg/kg to 14.8 mg/kg
hypothetically as a result of the increase in the activity of nitrifying bacteria following
a decrease in soil acidity after ash application. Maize yield in the greenhouse was not
significantly affected by ash or by other liming materials, and the sufficient watering
and consequent elimination of aluminium-induced drought stress is put forward as
having masked crop responses to acidity. In the field, coal ash reduced exchangeable
acidity from 10.0 mmolc/kg to 5.88 mmolc/kg, increased Ca levels from 71 mg/kg to
132 mg/kg, and increased Mg levels from 7.3 mg/kg to 17 mg/kg. The increase in
bean yield from 958 kg/ha to 1724 kg/ha by ash was similar to that realized by
dolomitic lime and calmasil. Gypsum had little effect on soil acidity, but it
substantially improved soil Ca and sulfate levels, and enhanced bean yield in the field experiment. The study demonstrated that coal ash could be effective as a liming
material, and underscores the need for a cost-benefit assessment of ash use
necessitated by the relatively higher rates of ash required to obtain significant soil and
plant responses.
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Determination of the lime requirement of sandy, organic-rich, and structured, high Mg:Ca ratio soils by the Eksteen methodSmuts, Michiel Nicolaas 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: The Eksteen method of lime requirement determination, based on the ratio of Ca+Mg:H (R-value), is widely used in the Western Cape and has proven to be extremely accurate for most soils. However, the Eksteen method is known to give erroneous predictions of lime requirement for certain soil groups. These include sandy soils (notably pale coloured sandy soils), organic-rich topsoils and strongly structured, Mg-rich subsoils. The objective of this study was to examine the nature of the Eksteen RpH relationship for these problem soils, and to develop appropriate modifications to the Eksteen method, where possible. A population of both normal and problem soils was selected and analysed, the RpH relationships of the soils were determined, and various relationships were examined. The principal findings with regard to the nature of the Eksteen RpH relationship were as follows: 1. The lime requirements of pale coloured sandy soils can be most accurately determined on an equivalent basis relative to the total extractable acidity, after the total extractable acidity has been corrected for residual lime. 2. The previously observed and acknowledged inaccuracy of the Eksteen method on organic-rich soils stems from the pH-dependant acidity component of the organic matter. The accuracy with which the lime requirement of these soils is predicted by the Eksteen method can be greatly improved by the application of an organic matter correction factor (OMCF) to the total extractable acidity, which is the parameter on which the lime requirement is then based. 3. In structured, Mg-rich subsoils the pH-neutralising capacity of Mg is considerably lower than that of Ca, a factor which is not taken into account by the Eksteen method. The Eksteen method can nevertheless be corrected to overcome this discrepancy. The high levels of Mg in the structured, Mg-rich subsoils cannot be attributed to minerals in these subsoils containing brucite interlayers. 4. Toxic levels of AI may only be expected at soil pH values below approximately 4.7 as determined in 1M KC!. Soil organic matter and CEC have marked affects on AI extractability. In accordance with the objective that appropriate modifications to the Eksteen method should be developed if possible, theoretically-based correction factors were developed which will permit the use of the Eksteen method to be confidently extended to those soil groups (pale coloured sandy soils, organicrich topsoils and strongly structured, Mg-rich subsoils) for which it was formerly considered unreliable. / AFRIKAANSE OPSOMMING: Die Eksteen metode van kalkbehoeftebepaling, gebaseer op die verhouding van Ca+Mg:H (R-waarde),
word oor die algemeen wyd in die Wes-Kaap gebruik en is baie akkuraat vir meeste gronde bewys. Dit is
egter bekend dat die Eksteen metode verkeerde kalkbehoeftes vir sekere grondgroepe voorspel. Hierdie
sluit sanderige grande (veral lig gekleurde sandgronde), organiesryke bogrande en sterk gestruktuurde,
Mg-ryke ondergronde in. Die doel van hierdie studie was om die aard van die Eksteen R:pH verwantskap
vir hierdie probleemgronde te bepaal, waar moontlik.
'n Populasie van beide normaal en probleemgrande is geselekteer en geanaliseer, die R:pH verwantskap
van die grande is bepaal en verskeie verwantskappe is ondersoek. Die hoof bevindinge ten opsigte van
die aard van die Eksteen R:pH verwantskap was as volg:
1. Die kalkbehoefte van lig gekleurde sandgronde kan akkuraat bepaal word op 'n ekwivalente
basis, relatief tot die totale ekstraheerbare suurheid, nadat die totale ekstraheerbare suurheid gekorrigeer
is vir residuele kalk.
2. Die voorheen bekende onakkuraatheid van die Eksteen metode op organiesryke gronde het sy
oorsprong by die pH-afhanklike suurheid komponent van organiese material. Die akkuraatheid waarmee
die kalkbehoefte van hierdie grande met behulp van die Eksteen metode voorspel kan word, kan
noemenswaardig verbeter word deur die totale ekstraheerbare suurheid te korrigeer met behulp van 'n
organiese materiaal korreksie faktor (OMKF). Die aangepaste totale ekstraheerbare suurheid is dan die
parameter waarap die kallkbehoefte gebaseer word.
3. In gestruktuurde, Mg-ryke ondergrande is die pH-neutraliseringsvermoe van Mg aansienlik laer
as die van Ca, 'n faktor wat seide in berekening gebring word by die Eksteen metode. Die Eksteen
metode kan tog gekorrigeer word om hierdie tekortkoming te oorkom. Die hoe vlakke van Mg in
gestruktuurde, Mg-ryke ondergrande kan nie aan die teenwoordigheid van minerale in die ondergrond,
wat brusiet tussenlae bevat, toegeskryf word nie. 4. Toksiese AI vlakke sal alleenlik by grond pH waardes laer as ongeveer 4.7, soos bepaal in 1M KCI, verwag word. Grand organiese materiaal en KUK het 'n noemenswaardige effek op ekstraheerbare
AI. In ooreenstemming met die doelwitte om toepaslike wysigings aan die Eksteen metode aan te bring, is
teoreties gebaseerde korreksiefaktore ontwikkel, wat die gebruik van die Eksteen metode verder
verbreed om daardie grondgraepe (lig gekleurde sanderige grande, organies-ryke bogrande en sterk
gestruktuurde, Mg-ryke ondergrande) in te sluit waarvoor dit vantevore as onbetraubaar beskou is.
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Attenuation of ionic pollutants in selected South African soilsMwepu, Mireille K. M. 03 1900 (has links)
Thesis (MScAgric (Soil Science))--University of Stellenbosch, 2007. / Two–thirds of South Africa, including more than 280 towns and settlements are
largely dependent on groundwater for their drinking water supply and development.
However, groundwater resources in South Africa are limited both in terms of quantity
and quality, especially in the semi–arid parts of the country (Sililo et al., 2001, p. i).
Therefore, the importance of protecting groundwater resources from pollution has
been recognized.
The first objective of this research was to investigate the attenuation capacity of a
selection of soil horizons and materials representing major types of diagnostic
horizons and materials in the South African soil classification in order to validate their
chemical attenuation ratings as provisionally specified by Sililo et al. (2001, p. 4.6).
The second objective was to assess the pollutant attenuation capacity of South
African soil horizons and materials as well as describe the diagnostic value of key
chemical properties of soils for conveying information on their contaminant
transport/attenuation potential. The third objective was to investigate whether it is
possible to apply acid/base priming using H2SO4 and Ca(OH)2 to a bulk quantity of
soil in order to reduce the mobility of contaminants.
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Soil fertility constraints to small-scale agriculture in North-west ZambiaSymons, Julia 03 1900 (has links)
Thesis (MScAgric (Soil Science))--Stellenbosch University, 2008. / The soils of north-west Zambia are largely unexplored and are regarded by local residents as problematic in providing sufficient nutrients for the staple crop of maize in the area. The area is semi-tropical, with an average rainfall of 1300mm annum-1 falling predominantly in the summer. The undulating landscape is dominated by miombo woodland interspersed with savanna grassland. Little work has been done on these soils and further information is required to understand their origin and their fertility status. The main objectives of this thesis were: 1) to classify and sample soils from a large number of small-scale agricultural lands, 2) to develop a better understanding of these soils chemical characteristics, 3) to determine the effect of vegetation clearance on soil fertility by sampling adjacent uncultivated land, and 4) to test locally derived rock dust as a soil ameliorant in pot trial.
Soils from 100 agricultural and adjacent bush/forest sites were classified and analysed to determine their fertility status. They were tentatively classified according to the WRB system and are dominated by Arenosols, Acrisols and Ferralsols with infrequent occurrences of Lixisols. Most of these soils have a sandy texture. The clay fraction comprises of gibbsite, kaolinite and hydroxyl-Al interlayered vermiculite (HIV), with a few soils also having some mica present. The soils are consistently acidic with 42% of soils sampled having a pH (KCl) <4.3. Furthermore, the subsoils proved to be equally if not more acidic than the topsoils. Low nutrient levels are invariably associated with the soil acidity, with 84% of soils having <15mg/kg P, 59% of soils <50 mg/kg K, 80% soils <300 mg/kg Ca, and 44% soils <80 mg/kg Mg.
Comparisons between cultivated and bushland soils showed no consistent changes to the soil acidity and fertility. This is contrary to research that was reviewed but is likely to have been affected by the spatial variability of these soils arising from the termite dominated landscape and the soils having been derived from different parent materials.
Amelioration of these soils is required in order to increase yields. It is thought that lime, used with an N, P, K, Zn and B fertilizer, will best remedy the deficiencies found in these soils. Using these nutrients could raise the yields of <1t.ha-1 to in excess of 5 t.ha-1. Local soil ameliorants of crushed rock, ash, compost, green manure and termite mounds were also considered with pulverised granite being tested through factorial pot trials to determine its usefulness as a source of K and alkalinity. It raised both soil pH and K levels but is of limited value as these rises were not significant enough to affect yield. It is recommended that future research should: 1) strategically sample across the district, classify soils and determine their fertility status; 2) compile a soil yield potential map and 3) undertake field trials to test the quantities and effectiveness of fertilizers alongside local soil ameliorants.
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Experiments to modify grape juice potassium content and wine quality on granite derived soils near PaardenbergAgenbach, G. 12 1900 (has links)
Thesis (MScAgric (Soil Science))--University of Stellenbosch, 2006. / High potassium content in grape juice and wine are associated with low
quality red wine in warm wine producing countries. In an attempt to reduce
the potassium content of juice, must and wine, a field experiment was laid out
on the farms Meerlus and Kersfontein in the Paardeberg area near Wellington
in 1998 on granite derived soils to investigate the effect of canopy
management and fertiliser applications on berry K accumulation and wine
quality.
Four fertiliser applications, three canopy treatments and a MgSO4 foliar spray
were studied. The three fertiliser treatments being: none (control), CaSO4,
Ca(OH)2, and MgSO4 applications. The canopy treatments were: thin to two
shoots per bearer, tip, vertical shoot positioning (VSP) and the removal of
yellow leaves and lateral shoots (canopy 1), thin to three shoots per bearer,
top after véraison and VSP (canopy 2) and VSP with top after véraison
(canopy 3/control). Magnesium sulfate sprays were applied at véraison for
two seasons (1999/00 and 2000/01).
Seasonal effects produced the most significant differences in this experiment.
Canopy treatments did not affect juice K concentration at harvest. Canopy 1
and 2 produced significantly lower wine pH values at Kersfontein. Fertiliser
treatments had no effect on juice K concentration nor did it affect wine
quality. Magnesium sulphate foliar sprays did not affect juice K concentration at harvest but significantly lowered juice and wine pH, improved wine colour
density and total phenolic content.
It appears for this experiment that soil K content before véraison, shoot
growth at and after véraison and water stress after véraison were the main
factors determining juice K concentration at harvest.
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Efficiency of irrigation practices for table grapes in the Hex River ValleyEustice, Tarryn 03 1900 (has links)
Thesis (MScAgric (Soil Science))--University of Stellenbosch, 2008. / In order to produce table grapes of export quality economically, irrigation must be practised
conservatively without adversely affecting the crop. To use water as conservatively as possible
effective irrigation scheduling practices must be applied. The highest water use efficiency (WUE) is
only possible if irrigation scheduling practices lower the amount of water applied, while at the same
time they increase the yield.
The first aim of this project is to investigate whether current irrigation practices make efficient use of
water by comparing irrigation requirements determined using theoretical models with actual irrigation
applied for two seasons (2005/6 and 2006/7). Secondly, the effect of cumulative irrigation on the
chemical status of soil in 16 blocks was investigated to establish whether nutrient leaching as a result of
differential water use may have had an influence on yield.
Six blocks (three dripper and three microsprinkler blocks) were selected and irrigation requirements
were determined using evaporation pan calculations, SAPWAT and Vinet and compared with actual
irrigation applications. Furthermore, a yield-irrigation index (kg/m3) and an income-irrigation index
(R/m3) were determined for each of the six blocks and compared.
To investigate the effect of cumulative water use on the chemical status of the soils of 16 blocks, soil
samples were taken and analysed for pH (1M KCl), EC (1:5); soluble cations and anions (Ca, Mg, Na,
K, SO4, NO3, and Cl), ammonium acetate extractable cations (Ca, Mg, Na and K) and micro elements
(Zn, Fe, Mn, Cu and B).
The irrigation requirements predicted by the different irrigation scheduling methods are variable. For
Vinet, the irrigation requirement determined for microsprinkler irrigation is much higher than that
determined using the evaporation pan or SAPWAT approaches. Comparison of the irrigation applied
to each of these blocks does not clarify whether any irrigation scheduling takes place. Results showed
a relationship between the yield-irrigation index and income-irrigation index. It has not however been
verified whether this relationship is statistically significant.
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The effect of saline irrigation on selected soil properties, plant physiology and vegetative reproductive growth of Palsteyn appricots (Prunus armeniaca L.)Volschenk, Theresa 12 1900 (has links)
Thesis (PhD (Soil Science))--University of Stellenbosch, 2005. / Approximately 45% of apricot tree plantings in South Africa are centered on Montagu, Koo and
Barrydale in the Little Karoo. Below average production in this area could be ascribed to the
deteriorating water quality of the Breede River and highly saline groundwater from boreholes
which provide this area with irrigation water. Profit margins for farmers are such that decreased
yields cannot be tolerated. Correct management of low quality water could improve production
and net farm income and could decrease irrigation return flow into the river system. The
objective of this work was to establish whether international water quality guidelines for apricot
are applicable under a different set of climatic conditions for a locally important cultivar and to
revise guidelines if necessary for the management of irrigation with saline water. A drainage
lysimeter was used to evaluate the effect of saline irrigation on apricot (Prunus armeniaca
cultivar Palsteyn) trees over a period of four years at Stellenbosch (S33° 55’; E18° 53’) in the
Western Cape.
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Sanjeevak as a source of nutrients and phytohormones for production and propagation of plantsOrendo-Smith, Richard 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The use of cowdung as an organic fertilizer in Asian and African agriculture is an
ancient practice. This explains its renewed interest, partly due to the financial inability
of most farmers to purchase agrochemicals but also the ever increasing need to adopt
greener technologies that do not adversely affect soil health, water quality,
biodiversity and promote sustained or even increased food production. In this context,
many innovative farmers have developed their own novel technologies based on the
use of local resources. One such innovation is Sanjeevak (a mix of cow dung, cow
urine, water and a handful of sugar); which showed very promising boosting effect on
crop productivity. However, very little scientific work has so far been conducted to
evaluate its effect as an organic product for soil amendments. The present study was
subdivided into three main objectives. (i) To assess the fertilizing value, human health
and ecological risk profiles of Sanjeevak; (ii) To screen Sanjeevak for phytohormones
content using Salkowski colorimetric method and liquid chromatography – mass
spectrometry (LC-MS) (iii) To evaluate Sanjeevak application at various rates on
growth parameters and yield of various crops cultivated in glasshouse and field
conditions.
Sanjeevak was assessed for its micro and macro nutrients contents. The
analysis showed the presence of micronutrients such as Mg, Na, Ca and Zn at variable
concentrations and phosphorus (P) (0.007%) and potassium (K) (0.063%). However,
Sanjeevak content in total nitrogen (TN) (0.11%), and total organic carbon (TOC)
(0.71%) was very low; suggesting that it may be a viable source of nutrients only if
applied at higher and consistent rates or alternatively by improving its formulation. Also, Sanjeevak was analysed for its microbiological characteristics and level of
heavy metals content in comparison to the strictest legislations that regulate the use
and application of wastewater sludge to agricultural land in South Africa. The
findings showed that heavy metals, which averaged from 0.03±0.01 for Arsenic (As)
to 4.74±0.92 mg/kg for Zinc (Zn) and feacal coliform was estimated at 1.2×102
CFU/g dry matter measured were considerably below the threshold (for Arsenic
between 40 to 75 mg/kg dry weight; for Zinc between 2800 to 7500 mg/kg dry
weight) and faecal coliform bacteria between 1000 to 1×107 CFU/g dry weight for
application as a source of soil amendments.
Studies investigating the detection and concentration of phytohormones in
Sanjeevak were carried out. In using the Salkowski colorimetric method to detect and
quantify auxins from Sanjeevak and its composites (cow urine and dung), the results
showed the presence of indole-3-acetic acid (IAA) at variable concentrations ranging
from 20.38±2.1 ppm in cow urine, 20.1±6.6 ppm in cow dung, Sanjeevak 17.90±1.1
ppm to up to 138.31±12.6 ppm when LTRP was added to Sanjeevak bacterial cultures
and by varying parameters such as incubaton time and temperature. Screening of the
above mentioned samples for IAA using LC-MS analysis validated earlier findings.
Further analysis of these results strongly emphasized the influence of bacteria in
Sanjeevak in producing IAA.
Trials were carried out both in the glasshouse and the field. In the greenhouse,
different Sanjeevak application rates consistently confirmed its root promoting effect
on crops such as tomato, cucumber and grapevine and increased wheat yield independent of the nutrients it contains. Marginal increases were recorded between treatments under field conditions; for example compost and compost + Sanjeevak
20.35 and 20.61 t/ha; and 2.46 and 2.60 t/ha compared to the control 11.67 t/ha and
1.29 t/ha respectively for tomato and maize. However, statistical analysis of the
results obtained, revealed that there was no difference between treatments (control,
compost, Sanjeevak and compost + Sanjeevak) for the same crop tested due to the
high coefficient of variation of the data.
Therefore, the use of Sanjeevak as an organic source of soil amendments may
be considered as a cheaper alternative to effective microorganisms (EM) technology
made up of local and natural resources. As observed in the study, it may be best used
in combination with a reliable source of plant nutrients. / RESUMEE: L'utilisation des excréments de vaches comme engrais organique dans l'agriculture
asiatique et africaine est une pratique très ancienne. Ceci explique son intérêt
renouvelé, en partie due à aux restrictions monétaires de la plupart des agriculteurs
d'acheter des produits agrochimiques, mais aussi la nécessité croissante d'adopter des
technologies vertes qui ne nuissent pas à la qualité des sols, des eaux, la biodiversité
et qui permettent d’améliorer la production agricole. C’est dans ce contexte que de
nombreux paysans ont développé des techniques nouvelles dépendant des ressources
naturelles et locales. L’utilisation de Sanjeevak (un mélange d’excréments de vaches,
d’urine de vaches, l'eau et du sucre), a démontré sa capacité à accroître la productivité
des plantes vivrières. Cependant, très peu de travaux scientifiques ont jusqu'à présent
été menée pour étudier ce produit organique. La présente étude a été subdivisée en
trois objectifs principaux. (i) Evaluation de la valeur fertilisante, et les profils de
risques écologiques et sanitaires de Sanjeevak, (ii) Etudes de détection des
phytohormones et leurs concentrations en utilisant une méthode colorimétrique
adaptée de celle de Salkowski et la chromatographie liquide - spectrométrie de masse
(LC-MS) (iii) Etude des effets de l’utilisation de Sanjeevak a différents taux
d’applications sur la croissance et le développement des plants. Sanjeevak a été évaluée pour son contenu en micro et macro nutriments. L'analyse a
montré la présence d'oligo-éléments tels que Mg, Na, Ca et Zn à des concentrations
variables. De plus, son contenu en éléments majors tels que le phosphore (P)
(0.007%), le potassium (K) (0.063%), l’azote (N) (0.11%), et carbone (C) (0.71%) est
très faible; suggérant qu'il pourrait être une source viable de nutriments que si elle est appliquée à des taux plus élevés et répétés ou alternativement en améliorant sa
formulation. En outre, Sanjeevak a été analysé pour ses caractéristiques
microbiologiques et sa concentration en métaux lourds en comparaison a la législation
qui réglemente l'utilisation et l'application de déchets liquide d’origines domestiques
sur les terres agricoles en Afrique du Sud. Les résultats ont révélé que des métaux
lourds et le niveau de coliformes fécaux mesuré était inférieur aux seuils d'application
en tant que source d'amendements de sols agricoles.
Les études portant sur la détection et la concentration d’hormones végétales ont été
effectuées. En utilisant la méthode colorimétrique de Salkowski pour détecter et
quantifier les auxines de Sanjeevak, les urines et les excréments de vaches; les
résultats ont révélé la présence d'acide indole-3-acétique (AIA) à des concentrations
variables dans les urines, les excréments et Sanjeevak. Une autre analyse des
échantillons mentionnés ci-dessus pour les AIA en utilisant LC-MS a validé les
résultats obtenus au préalable. L’étude détaillée de ces résultats confirme l'influence
des micro-organismes dans la production des hormones végétales. Concernant les expériences sous serre, les différents taux d'application de Sanjeevak
ont confirmé son effet stimulant à la croissance accélérée des racines des plantes telles
que la tomate et les raisins et augmenté le rendement du blé indépendamment des
nutriments qu'il contient. L'analyse statistique des résultats obtenus dans des
conditions de terrain, a révélé qu'il n'y avait pas de différence entre les traitements
(contrôle, compost, compost + Sanjeevak et Sanjeevak) pour la même plantes testées.
Par conséquent, l'utilisation de Sanjeevak comme un produit organique qui améliore
la qualité des sols et le rendement des cultures vivrières; peu être considéré comme un inoculum contenant des microorganismes constitué de ressources locales et naturelles.
Comme l'a observé dans l'étude, il pourrait être mieux utilisé en combinaison avec une
source fiable de nutriments végétaux. / AFRIKAANSE OPSOMMING: Die gebruik van beesmis as 'n organiese kunsmis in Asië en Afrika is' n eeu-oue
landbou praktyk. Dit verklaar die hernude belangstelling, deels vanweë die finansiële
onvermoë van meeste boere om landbouchemikalieë aan te koop, maar ook as gevolg
van die toenemende behoefte vir groener tegnologie wat nie nadelig is vir grond
gesondheid, waterkwaliteit, biodiversiteit en wat volhoubaarheid of selfs verhoogde
voedselproduksie bevorder. In hierdie konteks het baie vindingryke boere hul eie
nuwe tegnologie, gebaseer op die gebruik van plaaslik verkrygde hulpbronne,
ontwikkel. `n Voorbeeld hiervan is Sanjeevak ('n mengsel van beesmis, beesurine,
water en die handvol melasse), wat belowende bevorderende effekte op gewas
produktiwiteit en grond mikroflora getoon het. Tot dusver was daar egter baie min
wetenskaplike werk gedoen om die effek daarvan as 'n organiese produkte vir grond
wysigings te evalueer. Hierdie studie was verdeel in vier belangrike doelwitte. (i) Om
die bemestingswaarde, menslike gesondheid en ekologiese risiko-profiele van
Sanjeevak te evalueer; (ii) Om Sanjeevak vir fitohormone inhoud en vlakke met
behulp van 'n kolorimetriese metode afgelei van dié van Salkowski en
vloeistofchromatografie – massaspektrometrie (LC-MS) te besigtig; (iii) Glashuis en
veld waarneming reaksies met betrekking tot groei parameters en opbrengs van
verskeie gewasse na die toediening van Sanjeevak by verskillende tempos; (iv)
Laastens, om die effek van die Sanjeevak voorbehandeling op saad ontkieming en
voortplanting te toets in vergelyking met die metodes en tegnieke wat gereeld gebruik
word. Sanjeevak is geassesseer vir die mikro-en makro voedingstowwe inhoud. Die analise
het die teenwoordigheid van mikrovoedingstowwe soos Mg, Na, Ca en Zn by
wisselende konsentrasies, asook fosfor (P) (0.007%) en kalium (K) (0.063%), getoon.
Sanjeevak inhoud van totale stikstof (TN) (0.11%), en die totale organiese koolstof
(TOC) (0.71%) was egter baie laag, wat daarop dui dat dit slegs 'n lewensvatbare bron
van voedingstowwe is indien dit by hoër en konsekwente tempos toegedien word of
alternatiewelik wanneer formulering daarvan verbeter word. Sanjeevak was ook
ontleed vir die mikrobiologiese eienskappe en die vlakke van swaar metale in
vergelyking met die streng wetgewing wat die gebruik en toediening van afvalwater
slyk op landbougrond in Suid-Afrika reguleer. Die bevindinge het getoon dat swaar
metale en fekalieë kolivorm vlakke hier gemeet, aan die drumpel vereistes voldoen vir
die toediening as ‘n grondverbeteringsmiddel.
Studies wat die opsporing en die konsentrasie van fitohormone in Sanjeevak
ondersoek is uitgevoer. In die gebruik van die Salkowski kolorimetrise metode om die
ouksiene op te spoor en te kwantifiseer uit Sanjeevak en sy mengsel (beesurine en
mis), het die resultate die teenwoordigheid van indol-3-asynsuur (IAA) by wisselende
konsentrasies wat wissel van 20 tot 140 ppm in beesurine, beesmis en Sanjeevak
getoon. Evaluering van die bogenoemde monsters vir IAA met behulp van LC-MSanalise
bevestig vroeër bevindings. Verdere ontleding van hierdie resultate
beklemtoon sterk die invloed van Sanjeevak mikrobiota in fitohormone produksie. Proewe is uitgevoer in die glashuis en die veld. In die glashuis eksperimente, is het die
verskeie toedieningstempo van Sanjeevak herhalend die wortelbevorderende effekte
bevestig op gewasse soos tamaties, komkommer en wingerdstok en dit het opbrengs van koring verhoog, onafhanklik van die voedingstowwe wat dit bevat. Statistiese
analise van die resultate verkry onder veldtoestande, het getoon dat daar geen verskil
tussen die behandelings (kontrole, kompos, Sanjeevak en kompos + Sanjeevak) was
nie, gegee dat dieselfde gewas getoets was.
Ten slotte, laboratorium-eksperimente op Sanjeevak as voor-behandeling om die
beworteling te verbeter van die wingerdstok (Ramsey) onderstok steggies, het baie
belowende resultate getoon in vergelyking met naftaleen asynsuur (NAA) voorbehandeling
en die kontrole. Dit beklemtoon die feit dat Sanjeevak 'n alternatief kan
wees en wat verdere studie verdien, hoofsaaklik as gevolg van sy lae-koste en
omgewingsvriendelike prosedures.
Die gebruik van Sanjeevak as 'n organiese grondverbeteringsmiddel vir
gewasproduksie en voortplanting kan beskou word as' n goedkoper alternatief tot
effektiewe mikro-organisme (EM) tegnologie wat uit plaaslike en natuurlike
hulpbronne saamgestel is. Soos waargeneem in die studie, kan dit die beste gebruik
word in kombinasie met 'n betroubare bron van plantvoedingstowwe. Dus, moet die
gebruik daarvan vir die produksie van gewasse en voortplanting aangemoedig word.
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