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Code-switching among students at the University of ZululandMqadi, Praxedis Fikile January 1990 (has links)
Submitted in partial fulfilment of the requirements for the degree
of B.A. (HONS) in the Department of African Languages at
the University of Zululand, South Africa, 1990 . / The purpose of this research is to investigate why students at
the" University of Zululand code-switch. The research focuses
particularly on environmental and social factors which lead students
to code-switch. It also looks into the functions of code
switching. On the whole it is intended to contribute to the
findings already made on code-switching. Many researchers have
found out that people tend to code switch because it has become a
habit to do so. Such a reason does not sound linguistically convincing
to me. Others claim that people code-switch because they
want to display their 'education' or that they come from urban
areas or townships. This again is not convincing enough since
code-switching is a reality and would seem to come naturally. It
is not something one does when one feels like it is usually
done unconsciously.
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Tourism education policy applications in the Zululand District, KwaZulu-NatalNkumane, Bekelwangubani Maggie January 2008 (has links)
A dissertation submitted to the Faculty of Arts in
partial fulfilment of the requirements for the Master's degree
in Recreation and Tourism in the Department of
Recreation and Tourism at the
University of Zululand, 2008. / The study on Tourism Education Policy Applications in the Zululand District, KwaZulu-Natal was conducted against the background that, in spite of the fact that, although South Africa in general, and Zululand District in particular, is blessed with both natural and cultural attractions which enhance the tourism opportunities that can help to improve the economy, but the greatest deficiency in the tourism industry of South Africa is the absence of adequate tourism education and training. The lack of tourism education and training has been seen to result in a dearth of professional knowledge and skills in tourism, which are necessary for the development of the tourism industry. The study therefore, had specific objectives, which are the following:
(a) To reveal how tourism as a field of study is perceived and
understood by respondents within the study area.
(b) To establish the extent to which respondents in the Zululand
District are aware of tourism education.
(c) To investigate what tourism education policies are in place for
stakeholders in the study area.
(d) To determine the types of tourism education and training
programmes which are available for stakeholders in the Zululand
District.
(e) To find out whether existing tourism education policies are
implemented in a satisfactory manner in local schools in the study
area.
(f) To assess whether the local community participates in tourism
education in the study area.
A number of hypotheses directly related to the objectives of the study were postulated. The hypotheses were duly considered in an attempt to uncover the underlying causes of the identified discrepancies in the study area. The testing of the hypotheses was done through the analysis and interpretation of the data collected from the population sectors that are directly or indirectly affected in the study area.
The findings from analysis and interpretation showed that there is a lack of participation by the local community in tourism in general and in tourism education in particular. This is because the respondents lack knowledge and information about tourism education. It was indicated that there are no educational tourism activities or projects that are conducted to encourage them to participate. Lack of participation limits meaningful involvement and participation in tourism. If the community is not fully involved in tourism because of an inadequate tourism education they miss the various job opportunities that are offered by this industry.
The findings also revealed that the tourism educators do not implement the tourism education policy in a satisfactory manner in schools. The reason is that most of them lack the qualifications that are required to teach this learning area successfully. They lack the expert knowledge and experience needed to develop learners. Recommendations put forward aim to promote adequate tourism education in the study area.
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Effects of clear felling and residue management on nutrient pools, productivity and sustainability in a clonal eucalypt stand in South AfricaDovey, Steven Bryan 12 1900 (has links)
Thesis (PhD(For))--Stellenbosch University, 2012. / The subtropical ecosystem of the Zululand coastal plain is prized by the South African
commercial plantation forestry industry for its rapid clonal Eucalyptus growth, short rotations (6
to 7 years) and high yields. This region is typified by sandy soils that are low in clay and organic
matter, have small nutrient reserves and are poorly buffered against nutrient loss. The subtropical
climate induces rapid decomposition of residues and tree litter resulting in small litter nutrient
pools and rapid nutrient release into the soil, particularly after clearfelling. A combination of
large nutrient demands through rapid growth, rapid nutrient turnover and small soil nutrient
reserves implies that sites in this region are sensitive and may be at risk of nutrient decline under
intensive management. The work in this study set out to determine the risk of nutrient depletion
through harvesting and residue management on a site within the Zululand region, to assess
nutritional sustainability and the risk of yield decline in successive rotations. Some bulk
biogeochemical cycling processes of macro-nutrients nitrogen (N), phosphorus (P), potassium
(K), calcium (Ca) and magnesium (Mg) were assessed, and assessments also included sodium
(Na). An existing Eucalyptus stand was clearfelled and treatments were imposed on the residues after
broadcasting to simulate various levels of nutrient loss through levels of harvesting intensity and
residue management. These included residue burning (Burn), residue retention (No-Burn),
fertilisation (stem wood nutrient replacement), whole tree harvesting and residue doubling. Outer
blocks of the stand were not felled, but included as replicates of an undisturbed standing crop
treatment. Biogeochemical nutrient cycling processes were assessed primarily in the standing
crop, Burn and No-Burn treatments, in the assumption that these represented the furthest
extremes of nutrient loss. Data collection commenced a year prior to clearfelling and continued
to two years and six months after planting with key data collection over a 20.1 month period
from clearfelling to canopy closure (one year after planting). Water related nutrient pools and
fluxes were assessed as atmospheric deposition (bulk rainfall, throughfall and stemflow) and
gravitational leaching to 1m soil depth. Drainage fluxes were predicted using the Hydrus model
and real-time soil moisture data. Zero tension lysimeters collected soil solution for chemical
analysis. Sequential coring in the 0 to 30cm soil layer was used to determine in situ soil N
mineralisation. Soil chemical and physical properties were assessed over the first meter of soil at clearfelling and new crop canopy closure to determine soil nutrient pools sizes. Biomass nutrient fluxes were assessed from litterfall, residue and litter decomposition, and above ground accretion
into the tree biomass. Leaching and N mineralisation were monitored in the No-Burn, Burn and
standing crop treatments only. Atmospheric deposition, while variable, was shown to be responsible for large quantities of
nutrients added to the Eucalyptus stand. Nitrogen and K additions were relatively high, but
within ranges reported in previous studies. Rapid tree canopy expansion and subsequent soil
water utilisation in the standing crop permitted little water to drain beyond 1m resulting in small
leaching losses despite a sandy well drained soil. Further leaching beyond this depth was
unlikely under the conditions during the study period. Mineralisation and immobilisation of N
also remained low with net immobilisation occurring. The standing crop was shown to be a
relatively stable system that, outside of extreme climatic events, had a relatively balanced or
positive nutrient budget (i.e. nutrient inputs minus outputs).
Large quantities of nutrients were removed with stem-wood-only harvesting in the No-Burn
treatment leaving substantial amounts on the soil surface in the harvest residues. Whole tree
removal increased losses of all nutrients resulting in the largest losses of P and base cations
compared to all other treatments. This was mostly due to high nutrient concentrations in the
removed bark. Loss of N in the Burn treatment exceeded whole tree N losses through
combustion of N held in the harvest residues and litter layer. The majority of K leached from the
residues prior to burning and a relatively small fraction of the base cations were lost from the
partially decomposed residues during burning. Ash containing substantial amounts of Ca and
relatively large amounts of N and Mg remained after burning. Surface soil Ca and Mg was
significantly increased by the ash which moved into the soil with rainfall directly after burning. Rapid soil moisture recharge occurred within a few months after clearfelling, increasing leaching
from the upper 50cm of soil. Clearfelling increased net N mineralisation rates, increasing mobile NO3-N ions in the soil surface layers. Nitrate concentration peaked and K concentration dipped
in the upper soil layers of the Burn treatment directly after burning. Deep drainage and leaching
(beyond 1m depth) over the 20.1 month period was, however, not significantly different between
the Burn and No-Burn treatments. Rapid soil moisture depletion and nutrient uptake with new
crop growth reduced leaching fluxes to levels similar to the standing crop by six months after
planting. Taking the full rotation into account, clearfelling induced a short-lived spike in N and
cation leaching compared with the low leaching losses in the undisturbed standing crop. Soil N
mineralisation over the 20.1 month period in the burnt treatment was half that of the No-Burn
treatment.
Growth and nutrient accumulation was significantly higher in the fertilised treatment than in
other treatments up to 2.5 years of age. Growth in the Burn treatment was greatest compared to other treatments during the first few months, but slowed thereafter. No significant growth
differences were found between all other treatments from a year to 2.5 years after planting. Early
growth was therefore apparently not limited by N supply despite large differences in N
mineralisation between Burn and No-Burn. Foliar vector analysis indicated that fertilisation
improved growth initially through increased foliar N and P at six months after planting followed
by Mg and Ca at one year. The Burn treatment was not nutrient limited. These growth results
contrasted with similar international research on sandy tropical sites where growth was reduced
after residue removal and increased after residue doubling. The combined nutrients released from
pools in the litter layer or ash and soil in addition to atmospheric inputs were sufficient to
provide most nutrients required to maintain similar growth rates across all treatments. This
demonstrated the importance of residue derived nutrients to early growth nutrient supply.
Reduced N mineralisation through a lack of substrate may limit N supply later in the rotation
where residue had been removed. Construction of a nutrient budget for the system revealed that high levels of atmospheric inputs
have the potential to partially replenish a large proportion N, K, and Ca lost during clearfelling,
provided losses are constrained to stemwood removal only. However, loss of Mg that occurred
primarily through leaching may not be replaced under the low Mg inputs recorded in this study.
Larger nutrient removals (i.e. stemwood plus other plant parts) placed a heavier reliance on the
small soil nutrient pools at this site which can limit future productivity. More intense harvesting
and residue management practices dramatically increased the risk of nutrient depletion. Losses of
specific nutrients depended on a combination of clearfelling biomass removal, residue burning
and subsequent leaching. Nitrogen losses due to harvesting and burning were more substantial
than those due to leaching. Mg and K losses depended most strongly on the time after
clearfelling before re-establishment of the new crop and rainfall patterns, while Ca and P losses
depended directly on the amount of biomass removed. Depletion risk was the greatest for Mg
and K through rapid leaching, even after stem wood only removal. Deep root uptake and deep
drainage with associated cation loss needs to be investigated further to quantify ecosystem losses
and recovery of cations displaced beyond 1m. Atmospheric deposition is one of major factors countering nutrient losses. However,
atmospheric inputs may not be reliable as these may lessen in future through pollution control
legislation and climate change. Changes in growth rate under poor nutrient management
practices are small and difficult to detect relative to the large impacts of changing weather
patterns (drought), wildfire and pest and disease. This makes it difficult to prove nutrient related
growth decline. It may be possible that improvements in genetics, silvicultural technologies and atmospheric inputs may also be masking site decline (in general) and in part explain the lack of
evidence of a growth reduction in the region.
As the poorly buffered sandy soils on the Zululand Coast are at risk of nutrient depletion under
the short rotation, high productivity stands, it may be necessary to stipulate more conservative
harvesting and residue management practices. A more conservative stem-wood only harvesting
regime is recommended, retaining all residues on site. Residue burning should be avoided if N
losses become a concern. The length of the inter-rotation period must be kept short to reduce
cation leaching losses. Site nutrient pools need to be monitored and cations may eventually need
to be replenished through application of fertilisers or ash residues from pulp mills. Management
practices therefore need to be chosen based on the specific high risk nutrients in order to
maintain a sustainable nutrient supply to current and future plantation grown Eucalyptus.
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Browse : quantity and nutritive value of evergreen and deciduous tree species in semi-arid Southern African savannas.Penderis, Caryn Anne. 06 November 2013 (has links)
Browse selection, intake, utilisation, palatability, quality and production are tightly linked and need to be considered together in trying to improve our understanding of browsing dynamics and the interactions between browsers and vegetation. Such an understanding is necessary in order to re-evaluate determinations of browser carrying capacities and evaluating actual and potential impacts of browsing animals on vegetation composition and diversity. Browser carrying capacity is determined by both the quantity and the nutritive value of forage. The measurement of browse quantity and nutritive value and the matching of browse supply to browser demand are central to sustainable utilisation and the monitoring of vegetation health.
South African savannas are poorly studied with respect to tree canopy growth and browse production making it difficult to quantify the available browse biomass on which browsing capacity estimations are based, and consequently difficult to estimate levels of browsing that are sustainable. This study addressed these issues by investigating browse dynamics, broadly aiming to (1) explore factors affecting browse production, biomass and nutritive value; (2) develop models to assess and monitor these parameters across seasons and properties; (3) use the resultant models in improving our understanding of how to determine browser carrying capacities. More specifically, our study sought to examine the effects of plant physiognomy, forage nutritive value, canopy stratum, defoliation, temperature, rainfall and soil nutrient status on the browse production of evergreen (Carissa bispinosa, Euclea divinorum, Gymnosporia senegalensis), semi-deciduous (Spirostachys africana, Ziziphus mucronata) and deciduous (Acacia nilotica, Dichrostachys cinerea) savanna tree species from June 2003 – June 2005 in three sites along the northern Zululand coastline of KwaZulu-Natal.
Available browse biomass, during the dry season, of four key savanna tree species (A. nilotica, E. divinorum, G. senegalensis, and S. africana) was estimated through the development of allometric regression equations. Non-linear regression was used to investigate the relation between the leaf dry mass (LDM) and canopy volume (CVol) of each of the four tree species. Exponential regression (y = a + brlnx) of the natural logarithm of CVol data provided the most accurate and precise description of the tree CVol – LDM relation.
A study was undertaken to determine which factors may influence browse production in a southern African savanna. Regression tree models for the browse production identified that the dominant factors influencing browse production were CVol (m3), season, species and height to the lowest leaves of the tree canopy (HL) (m). The length of the growing season had a marked effect on the production potential of savanna tree species, suggesting that improved conditions for growth, i.e. greater rainfall, soil moisture content and improved soil nutrient availability result in a longer period of rapid sustained growth. Species was identified as an important contributing factor to differences in browse production rates, suggesting the need for the development of species or species group models.
Mean annual browse production of evergreen trees was greater than that of deciduous and semi-deciduous trees. Mean quarterly (three monthly) browse production was highest, for all trees, during the wet season, with the greatest difference between wet and dry season production being observed in deciduous forms. Evergreen forms showed continuous growth over the whole study, with enhanced growth over the wet season. Deciduous forms, on the other hand, concentrated growth in spurts, when environmental conditions became favourable, with most production occurring during a short growing season.
Browse nutritive value was found to be greatest during the wet season, when growth and photosynthesis are at their greatest. Further, browse nutritive value was greatest in deciduous species. Evergreen trees were found to have greater acid detergent fibre (ADF) concentrations than both the deciduous and semi-deciduous trees. By contrast, crude protein (CP) concentrations were greater in semi-deciduous and deciduous species than in evergreen species.
The daily CP requirements for maintenance for an adult impala (45 kg) were met by all species over all three study areas and all seasons. Daily CP requirements for growth and lactation, however, were only ever met by deciduous and semi-deciduous species, though this result was not consistent over study areas and seasons.
Predictive models for the production of browse on deciduous, semi-deciduous and evergreen trees in northern Zululand were developed using multivariate adaptive regression spline functions. The best predictors of growing season browse production in all three tree guilds (defined here as a group of trees having a characteristic mode of living) were primarily measurable tree dimensions, while the prevailing environmental conditions had little impact.
Differences in the production, nutritive value and available browse biomass between the different tree forms and seasons have a profound effect on the determination of browser carrying capacities and need to be incorporated into any game or conservation management plan. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
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Small-scale timber growers' participation in the development of national principles, criteria, indicators and standards for sustainable forest management in South Africa.Ngubane, Steven Zama. January 2005 (has links)
The aim of this study was to engage small-scale timber growers in the development of
national principles, criteria, indicators and standards (PCI&S) for sustainable forest
management (SFM) in South Africa (SA).
To ensure effective participation of small-scale timber growers in the development
PCI&S, an overview of sustainable and small-scale forestry was explored.
Furthermore, because of the importance of globalisation on the SFM concept, its
conceptual framework and small-scale forestry development in relation to SFM were
investigated.
Participatory rural appraisal (PRA) methods, and PCI&S evaluation and development
processes were used to engage small-scale timber growers by identifying and
integrating their perceptions into the process of SFM standards development. These
small-scale timber growers' perceptions focused on social, economic, environment
and policy issues.
The stUdy indicates that the views of small-scale timber growers regarding SFM do not
vary significantly from those held globally. However, they demonstrate that local
conditions determined issues of relevance and importance to this specific group. The
results further support the view that there is value in combining both top-down and
bottom-up approaches in developing an appropriate set of PCI&S. This is critical
because the perceptions of small-scale timber growers for SFM are scale sensitive.
Finally, the results supported the view that there is a need to give attention to and
strengthen socio-economic issues versus those of the physical environment to
improve inequalities of the past, and influence future decisions. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.
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The food safety knowledge of street food vendors and the sanitary conditions of their street food vending environment, Zululand District, South AfricaNkosi, Nelly Virginia 01 1900 (has links)
Street-vended foods are convenient and cheap meals, but their contamination can lead to
foodborne illness. This study aimed to evaluate food safety knowledge of street food vendors in
Ulundi and AbaQulusi local municipalities of Zululand District, South Africa and compliance of
their street food vending environment to sanitary requirements. A cross sectional survey design
was utilised to gather data from 400 street food vendors using interviews. A piloted checklist was
used to collect data on the sanitary characteristics from 200 randomly selected street food
vending facilities. Most of the street food vendors were black (99%), females (73%), and above
35 years (55%). Only the minority of street food vendors had attended a high school (47%) and
the vast majority (77%) of them had not attended any food safety training course. The majority
(64.7%) of respondents knew that food should not be handled when they have diarrhoea, even if
their hands were washed regularly, neither when they have flu, colds, cough, or catarrh. The
minority (43%) of street food vendors knew that the use of separate cutting boards for meat and
salad, and washing them between uses are the safest ways to avoid cross-contamination. The
majority (79.4%) of street food vendors were aware that microorganisms could cause foodborne
diseases that may lead to death. The vast majority (76%) of street food vendors had low food
safety knowledge and only 14% of the street food vending sites had high compliance with
sanitary conditions. In conclusion, most street food vendors possessed inadequate food safety
knowledge in key food safety parameters and most of the street food vending facilities were noncompliant.
Furthermore, most of them operate under poor sanitary conditions. Street food
vendors should be provided with compliant waste disposal and standard kitchen facilities with
water resources to ensure hygienic preparation and serving of food. / Life and Consumer Sciences / M. Cons. Sci.
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The transfrontiersman : the career of John Dunn in Natal and Zululand 1834-1895.Ballard, Charles Cameron. January 1980 (has links)
No abstract available. / Thesis (Ph.D.)-University of Natal, Durban, 1980.
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An investigation into estimating productivity, above ground biomass and leaf area index of Eucalyptus grandis using remotely sensed data and a process-based model.Mzinyane, Thamsanqa D. January 2007 (has links)
South Africa depends largely on afforestation programs for its timber supplies due to the great demands for fiber and wood products. This has brought discomfort to other water users who have advocated that the effects of afforestation on water resources are detrimental to the country as a whole since South Africa is known as a water scarce country. This study has undertaken to integrate a process-based model and remote sensing data to estimate water use and productivity of Eucalyptus grandis in the Zululand areas of South Africa. The remote sensing techniques and recently developed "process based model" that is 3PG-S were used to estimate water use and productivity of Eucalyptus grandis, an economically important plantation species grown in the summer rainfall areas of South Africa. The study utilized monthly Landsat Thematic Mapper datasets and climatic data as inputs into the 3PG-S model, determined the Leaf Area Index (LAI) and Specific Leaf Area (SLA) through direct (destructive sampling) and indirect measurements (LiCor- 2000) and assessed the relationships between various vegetation indices (VI's) using correlation and regression analyses. The results suggest that all the indices, except the ratio VI, correlated significantly with LiCor-determined and destructively measured LAI values with both normalized difference vegetation index (NDVI) and Ratio Vegetation Index (RVI) (r=0.86, p / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritburg, 2007.
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Role enactment of rural women : a sociological-exploratory study of role behaviour and its implications for rural developmentNene, Daphne Sbongile January 1982 (has links)
Submitted to the faculty of Arts in fulfillment of the requirements for the degree of Master of Arts in Sociology in the Department of Sociology at the University of Zululand, South Africa, 1982. / The study is concerned with the role of rural women in society. It
focuses on a typically agricultural, grass-root community where the
forces of traditional Zulu culture are still at work in family and clan
relationships. This traditional way of life is retained and enforced
through the most powerful institutions of religion and politics. Thus
the authority structure and religious philosophy permeate interpersonal
relationships giving them a character which is distinctively rural.
Architecture, mode of dress, dietary habits and household settlement
attest to the rurality of the community.
This is an exploratory case study of a small section of a larger commu=
nity, and which section represents the overall ~eneral character of the
community. Although typically rural in terms of value and normative
system, nevertheless it is already being steadily exposed to elements
of an industrial society e.g. a money economy, agricultural technology,
formal schooling and outmigration of male workers. We therefore see in
this microcosm two forces at work - traditional as well as modern. The
research population is representative of a traditional community in
transition.
The study focuses on role-behaviour of rural women and its implications
for development. The research group is already partially exposed to the
effects of rural development. To what extent their present role affords
them meaningful participation and benefit from their community's
changing status will be revealed with greater clarity as their particular
role-behaviour,within their given environment, is analysed.
With respect to rationale for choosing this particular group, we can
argue that they are the most suitable respondents on whom to do research which focuses on rural behavioural patterns, on the one hand, and social
change and development on the other. The population is neither totally
isolated in its rural social system nor influenced by forces of
modernisation to the extent that the basic cultural ~radition is
effaced.
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The effect of wood ash on the soil properties and nutrition and growth of Eucalyptus grandis x urophylla grown on a sandy coastal soil in ZululandScheepers, Gerhardus Petrus 12 1900 (has links)
Thesis (MScFor)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: A field trial of six replications was established to test the effect of various wood ash and fertilisers application rates on soil chemistry, tree nutrition and early growth rate of a clonal Eucalyptus grandis x urophylla stand. Wood ash from pulpmills is currently disposed of in landfills. Increasing costs and potential environmental risks have driven companies to investigate alternative disposal methods. Ash consists of a combination of carbonates, hydroxides and other calcium containing minerals that induce the liming effect if ash is applied to a soil. The trial was established near Richards Bay in October 2013 on a sandy soil with a low buffer capacity and a pH of approximately 5.5. The trial consists of four wood ash application rates in combination with three levels of fertiliser, viz. no fertiliser, 150 g conventional NPK fertiliser mixture, or 320g NPK controlled release mixture. Fertiliser mixtures and application levels were based on previous fertiliser trials in the region. Ash application rates for the field trial were based on a lab incubation study done with soil samples from Richards Bay, to which increasing amounts of lime were added. The study tested wood ash application rates of 0, 300, 600 and 1200 kg/ha. Field measurements were taken at 4 and 8 months after trial establishment. The primary objective was to investigate which application levels in combination with the type of fertiliser could be applied to soils without negatively affecting the stand nutrition or increase the levels of potentially harmful elements in the soil; thus investigating the feasibility of safely disposing wood ash on plantation soils as an alternative disposal method. Soil nutrient concentrations were not affected by individual wood ash treatments, but more a product of the time interval after the ash additions were made. Soil C, P, K+ and Mg2+ showed decreased concentrations from 4-8 months after establishment. Ca2+ concentrations increased in the same time interval. In addition, Na+ and B concentrations decreased from 4-8 months. Soil heavy metal concentrations for Cd, Hg, Cr and Pb, analysed for 0-1200 kg/ha ash rates, were well below toxic levels at both time intervals. Wood ash induced a temporary liming effect. Mean soil pH increased with 0.6 units for the period 0 - 4 months and decreased with 0.4 units at 4 - 8 months after trial establishment. Foliar nutrient analyses and assessment techniques revealed sub-optimal nutrient concentrations for P, K and Zn at 4 and 8 months of age. Concentrations were defined as sub-optimal, as none of the nutrients were below critical levels. Foliar heavy metal concentrations for Cd, Hg, Cr and Pb, measured at both time intervals, were less than 1mg/kg. The small concentrations found in this project were attributed to the low bioavailability of all four elements and were likely a product of the edaphic factors at Richards Bay, which was representative of a large greater portion of the Zululand coastal plain sites. The response in biomass index ranged between 13 % and 683 % relative to the control treatment (A0F0). Results showed that application of purely wood ash, or in combination with a supplementary N and P source increased growth up to 8 months after trial establishment for wood ash applications up to 1200 kg/ha. This project demonstrated that 1200 kg/ha wood ash can safely be disposed of on a typical Zululand coastal sand with little environmental risk and no supressed growth, provided that it is balanced with an appropriate NP fertiliser. / AFRIKAANSE OPSOMMING: ‘n Veldproef met ses herhalings is in Oktober 2013 uitgelê met die doel om die uitwerking van verskillende vlakke hout as en kunsmis toedienings op die grond-voedingstof status, boom-voedingstof status en die groei-tempo van ‘n Eucalyptus grandis x urophylla hibried plantasie te bestudeer. Hout as by pulpmeulens word tans weggegooi op stortingsterreine. Toenemende onkostes vir storting en die omgewingsrisiko’s gebonde aan stortingsterreine, dryf maatskappye om verbeterde en meer omgewingsvriendelike metodes te ondersoek om van die as ontslae te raak. Hout as bestaan uit ‘n reeks karbonate, hidroksiede en kalsium bevattende minerale en is verantwoordelik vir die bekalkingseffek op die grond na toediening. Die veldproef is geleë naby Richardsbaai op ‘n sanderige grond met n lae bufferkapasiteit en pH van ongeveer 5.5. Die proef het vier hout as vlakke getoets, gekombineer met drie vlakke van bemesting: geen, 150g konvensionele landbou kunsmis (CV) óf 320g beheerd-vrystellende kunmis (CRF). Die kunsmismengsels en vlakke van bemesting is gebaseer op bestaande of voltooide bemestingseksperimente in die streek. Hout as vlakke was bereken in gekontroleerde laboratorium toestande en gebaseer op ‘n inkubasie studie met grond monsters verkry vanaf Richardsbaai, waarby toenemende vlakke suiwer landboukalk gevoeg is. Die veldproef het hout as vlakke van 0, 300, 600 en 1200 kg/ha getoets. Veld metings is op 4 en 8 maande na behandeling geneem. Die primêre doelwit van die studie was om te bepaal watter vlak hout as en kunmis kombinasie toegedien kan word, sonder om die grond-voedingstof status negatief te beïnvloed of ‘n potensiële skadelike uitwerking op die plantasie groei te veroorsaak. Die uiteinde van die studie was om die haalbaarheid van hout as toedienings op plantasie gronde te bestudeer relatief tot die huidige praktyk van storting, insluitend die risiko van moontlike skadelike newe-effekte. Grondvoedingstatus was nie beduidend beïnvloed deur individuele hout as toevoegings nie, maar was eerder ‘n funksie van die tydsduur sedert behandeling. Grond koolstof, P anione, K+ en Mg2+ konsentrasies het beduidend afgeneem in die periode van 4 - 8 maande na behandling. Die Ca2+ konsentrasies het toegeneem tussen 4 en 8 maande en terselfdertyd het Na+ en B konsentrasies afgeneem. Die swaarmetaal status, spesifiek vir Cd, Hg, Cr en Pb, vir toevoegings van 0-1200 kg/ha hout as was beduidend laer as toelaatbare vlakke in gronde op albei tydsintervalle. Die hout as het ‘n tydelike toename in grond pH veroorsaak. Die gemiddelde pH het tussen 0 - 4 maande toegeneem met 0.6 eenhede en gedurende 4 - 8 maande afgeem met 0.4 eenhede.
Blaarontledings en voedingstof assesseringsmetodes het sub-optimale konsentrasies vir P, K en Zn getoon op die ouderdom van 4 en 8 maande. Voedingstof konsentrasies is as sub-optimaal geklassifiseer, omdat konsentrasies nooit laer as kritieke waardes vir gebreksimptome was nie. Die inhoud van Cd, Hg, Cr en Pb in blare was aansienlik kleiner as 1 mg/kg op albei tydsintervalle. Die merkwaardige lae konsentrasies wat in die projek aangeteken is, word toegekryf aan die lae bio-beskikbaarheid van al vier elemente as gevolg van die edafiese faktore eie aan die Richardsbaai omgewing (en ook aan groot dele van die Zoeloelandse kusvlakte). Die groeireaksie (bepaal as biomassa indeks op ouderdom 8 maande) het gewissel van 13 % - 683 % groter as die kontrole behandeling (A0F0). Resultate het bewys dat toedienings van suiwer hout as, of hout as gekombineer met ‘n addisionele N en P kunsmisbron die groei postief beïnvloed tot op die ouderdom van 8 maande. Die studie het bewys dat 1200 kg/ha hout as veilig toegedien kan word op die sandgronde van die kusgebiede in Zululand, met minimale omgewingsrisiko en geen tekens onderdrukte groei nie, mits dit gebalanseer word met ‘n geskikte NP kunsmisbron.
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