Controlled release fertiliser as a management tool for productivity of tunnel-grown tomatoes

Thesis (MScAgric)--Stellenbosch University, 2022.ENGLISH ABSTRACT: To be able to grow crops such as tomatoes on a commercial scale under stringent controlled conditions in what is termed controlled environment agriculture (CEA), requires a great amount of expertise and technology. Therefore, the aim of this study was to see if the use of controlled release fertilizer as an alternative low expertise and low technology-based fertilization method could produce the same yields and marketability than the conventional fertigation fertilization methods used in greenhouse tomato production. The study assessed this by (1) determining if the ratio of perlite to coco coir in the growth medium had any effect on the yield response to an industry recommended controlled release fertilization recommendation, (2) trying to establish an appropriate mixing ratio of controlled release fertilizer (CRF) and liquid fertilizer (LF) to determine if a follow up fertilization application of the pre-plant applied CRF can obtain improved yields. From the results it was evident that by applying a mixture of 80% CRF (based on the fraction of the total % nitrogen applied) and 20% LF with additional monthly manual application of calcium sulphate or calcium nitrate to each planting bag, CRF could potentially replace a 100% LF fertilization programme in greenhouse tomato production. Some results here indicate that a spike in temperature at the beginning of the growing season may have contributed to the premature release of nutrients from the CRF prill, causing a spike in EC. This stunted the growth of the plants for the rest of the season, which could have been attributed to an initial toxic level of salts in the rootzone and a prolonged deficit of other essential nutrients. The growth media trial for the determination of the optimal perlite: coco coir ratio revealed that a mix consisting of 20% perlite to 80% coco coir, or 40% perlite and 60% coco coir were the best ratios that yielded the highest. Thus, for tomato production the effect of CRF would be greatly improved if applied in an environment where the temperature and growth media properties are favourable for the slow release of the nutrients. The evidence here did not support the utilisation of 100% CRF as a replacement of the currently employed LF for commercial greenhouse tomato production. In addition, it is imperative that additional calcium (Ca2+), Sulphate (SO42-) and Nitrate (NO3-) be supplemented to reap the full benefits of CRF due to the ongoing technological research into the ability to coat calcium-based fertilizer products as a CRF.AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar.Master

Rangeland condition in the Tembe Traditional Area, Maputaland, KwaZulu-Natal, South Africa

This study, undertaken under the auspices of the Centre of Wildlife Management and the former Centre for Indigenous Knowledge (University of Pretoria) was conducted in Maputaland, with special reference to the Tembe Elephant Park, Sileza Nature Reserve and in the neighbouring traditional wards (izigodi) of Mbangweni, Bhekabantu, Kwandaba, Zama-zama, Tsokotho, Manqakulani (which includes the Tshanini Community Conservation Area), Lulwane, Mntikini, Ndlondlweni, Ndovu and Sibonisweni. The main objective of this study was to evaluate the range condition and grazing capacity of the natural veld. A management plan for the Tshanni Community Conservation Area is presented, which could potentially serve as template for similar areas. To accomplish these objectives a cattle as well as a vegetation survey were conducted. The cattle surveys were conducted among the local communities (mentioned above) to identify and to evaluate the role played by cattle in the everyday lives of the communual people and to identify the types of grazing regime (practices). The vegetation surveys were undertaken to evaluate the range condition, grazing capacity and grazing quality of the herbaceous vegetation. The study also included methods to determine the number, distribution and health status of cattle present in the study area. The results indicated that social and religious values that were associated with cattle in the older Zulu culture have clearly faded in the Tembe Traditional Area. The current values of local communal people regarding cattle were concentrated on utilization and investment for future uncertainties. Cattle were still seen as wealth and status symbols in the local communities and were highly prized possessions if they could be obtained. The official cattle numbers did not seem to reflect the actual cattle numbers in the study area at the time of study. It was also clear that cattle were distributed in areas where the water supply was sufficient. The main grazing areas were thus in the east of the study area in the hygrophilous vegetation to the east of Manqakulani and mainly in Ndlondlweni. No specific grazing management practices could be identified and the grazing system could be best described by a continuous grazing practice. Grazing was not restricted to any part or piece of land inside the specific isigodi as long as the cattle stayed out of other people’s cultivated land. Overstocking the grazing area was not occurring at the time of the study as the stocking density was well below the area’s capacity. The general perception of the majority of the cattle owners was that their cattle were in a good condition. An analysis of the results obtained from the vegetation survey indicated that the herbaceous biomass yield did not vary noticeably among the management units within a site as well as among the different sites. The small fuel loads in the Tshanini Community Conservation Area did not necessitate burning and were probably below fuel loads needed for fires to spread. However, it was frequently observed that fire could be maintained in areas where the herbaceous biomass yield was below 2 000 kg/ha. The results represented in this study also indicated that the management units of the Tshanini Community Conservation Area were generally in a good condition and that the range condition of the Tshanini Community Conservation Area compared relatively well with the other reserves in the study area. The modified Ecological Index Method was reliable and time saving, yet simplistic enough for assessing the range condition of the management units of the Tshanini Community Conservation Area and the entire Tembe Traditional Area. The stocking density must be adaptable and based on the quantity and quality of grazing available at any time. The model that was used to calculate the stocking density of the study area allows for several elements to be modified to suit the conditions on a particular wildlife reserve at a particular time. For example, in future it may become necessary to adjust the percentage composition of graze and browse in the diet of some animal types for the calculation of Grazer Units (GU) and Browser Units (BU), mainly because the diet of the same type of animal may vary regionally. Finally, changes in the choice of the types of wildlife can be accommodated depending on the preferences and objectives of the management and steering committee of the Tshanini Community Conservation Area. This model can be applied as a tool for active adaptive management because it allows more control over the quantity and quality of available food plant resources and hence the stocking density of animal resources. It is proposed that the results of the present study be combined and integrated into a Geographic Information System (G.I.S.) database that could form the ecological basis for future management planning of the Tembe Traditional Area as part of the Usuthu-Tembe-Futi Transfrontier Conservation Area.Dissertation (MSc)--University of Pretoria, 2009.Animal and Wildlife Sciencesunrestricte

An explorative study of serial rape and victimisation risk in South Africa.

Serial rape attracts much media attention and has become a topic of increased interest and concern. However, both locally and internationally, there is a paucity of empirically based research. The limited research which exists often does not focus on the victim as a “subject” which could contribute to solving existing cases or in curtailing the serial rapist. In this article, socio-demographic characteristics of 75 victims of serial rape, and how they were selected by the rapist were used to construct a general profile of the people who are the targets of the serial rapist. Factors or contexts which put women at risk are also identified and investigated. Comparisons are made between the characteristics of the victims of serial rapists in other countries, while comparisons are also made between the victims of single-victim rapists and those of the serial rapist. Of great concern is, amongst others, that the results indicate that in South Africa a large number of victims of the serial rapist are girl children. Limitations of the research are indicated, while a suggestion for future research concludes the article

Psalm 56 read within its literary context in the Psalter and its connections with King David

The heading of Ps 56 connects the psalm with “David,” and specifically with the time when he was “seized” by the Philistines in Gath. The psalm can be described as a lament with a strong emphasis on trust in God and praise for his word. This article investigates the reasons why the editors made this connection with the experience of David and how the intertextual connections this heading creates modifies the hermeneutical horizon of the psalm. It is suggested that the psalm, in view of its heading, serves to exonerate David from the fear that he experienced according to 1 Sam 21:13. It also focuses the attention of its readers on the way in which David triumphed in a situation of unjust persecution through his trust in Yahweh in order to walk freely in praise of God.http://reference.sabinet.co.za/sa_epublication/oldtestam201

The structure and homogeneity of Psalm 32

Psalm 32 is widely regarded as a psalm of thanksgiving with elements of wisdom poetry intermingled into it. The wisdom elements are variously explained as having been present from the beginning, or as having been added to a foundational composition. Such views of the Gattung have had a decisive influence on the interpretation of the psalm. This article argues, on the basis of a structural analysis, that Psalm 32 should be understood as a homogeneous wisdom composition. The parallel and inverse structure of its two stanzas demonstrate that the aim of its author was to encourage the upright to foster an open, intimate relationship with Yahweh in which transgressions are confessed and Yahweh’s benevolent guidance on the way of life is wisely accepted.http://www.hts.org.zahb201

“David” in consultation with the prophets : the intertextual relationship of Psalm 31 with the books of Jonah and Jeremiah

Psalm 31 seems to be a late post-exilic text. It displays numerous similarities with other psalms, and also with the prophetic books of Jonah and Jeremiah. This paper proposes to investigate the nature of the literary relationship with the prophetic books in an attempt to establish the direction of influence and to determine the reasons why the psalm seems to have been composed as a kind of literary anthology. It would seem that the group of people who were responsible for composing Ps 31 also contributed towards the insertion of the confessions of Jeremiah and the prayers of Jonah.http://www.journals.co.za/ej/ejour_oldtest.htmlnf201

The profile of the rich antagonist and the pious protagonist in Psalm 52

In this article, a stichometric and poetic analysis of Psalm 52 is offered which forms the basis for a description of the character of the rich but crooked antagonist and the pious protagonist in the psalm. The profile of the pious in the psalm emerges largely as the inverse of the inclination and actions of the arrogant, rich antagonist who is addressed in the greater part of the psalm. The psalm is also read and interpreted against the background of the book of Psalms as a whole to argue that Psalm 52 is actually describing the opposition between the righteous and the wicked as it is typically found in Wisdom psalms.http://www.hts.org.zaam201

Narratologiese ondersoek van die boek Jona

'Obwohl das Buch Jona sehr klein ist, hates der friihchristlichen Kunst und der Auslegung bis auf unsere Zeit vie/ Anregung gegeben; denn "dies scheinbar so alberne Biichlein gehort zu dem Tiefsten und Grossartigsten, was jemals geschrieben worden ist"' (my beklemtoning). Met hierdie woorde bring Loretz (1961:18) die paradoks tussen die lengte en die verstaanbaarheid van die boek treffend na vore. By die nagaan van die wetenskaplike literatuur oor Jona word hierdie paradoks al hoe duideliker. 'n Mens kom onder die indruk van die diversiteit van menings oor die boek wat gestalte vind in uitdrukkings soos 'the odd little tale' (Burrows 1970:80) en Luther se uitroep: 'Hilf Gott, welch ein wunderlich Werk is doch das!' (Von Rad 1974: 65). Daar is veral drie sake wat baie nou met mekaar saamhang, naamlik die komposisie, die literatuursoort en die boodskap, wat as probleemareas van die boek genoem word. Soveel uiteenlopende oplossings word vir hierdie drie probleemaspekte gebied dat daar inderdaad gese sou kon word dat daar 'n Babelse verwarring oor hierdie aspekte van die boek heers. As die lengte van die boek in ag geneem word, is dit inderdaad 'n vreemde en unieke situasie.hb201

A descriptive study of the modus operandi of serial rapists in South Africa.

This article reflects research of which the aim is to increase our collective knowledge of the modus operandi of serial rapists in South Africa in an attempt to contribute to the prevention and prosecution of perpetrators. The sample consists of 22 convicted cases of serial rapists and reflects 204 victims. The authors note that a mere understanding of the modus operandi of serial rapists is not sufficient to fully understand the behavior of these perpetrators. However, they draw attention to the argument that understanding the perpetrator’s modus operandi has been recognized by both criminal investigators and academics as making a valuable contribution to understanding crimes, including that of serial rapists. A behavioural checklist was developed to provide assistance with accounting for the chronological pattern of the crime from the time of victim acquisition to the actual attack. The rational choice perspective and routine activity theory were then used as an organizing framework within which to analyse the strategies of the perpetrator. The results indicated that the modus operandi exhibited by a group of serial rapists in South Africa differs from offenders in other countries. Aspects of the routine activity theory is contextualized and utilized to interpret the current findings. The authors highlight shortcomings of the current research and suggest how the current findings should form the basis of further research