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Thesis (MScFor)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Agroforestry researchers in Eastern Zambia have identified improved fallows as an intervention for soil fertility problems faced by small-scale farmers. In both on-station and on-farm research experiments which have been conducted since 1989, results have shown that improved fallows can mitigate soil degradation and eventually improve land productivity. Both researchers and extensionists have since embarked on disseminating these fallows to the farming community. Researchers were initially entirely dependent on the conventional agricultural extension services to disseminate the technology to the farmers but the process was slow and so was the uptake for the technology by farmers. As researchers were anxious to see that farmers took up improved fallows in a fastest possible way, they opted to use alternative dissemination pathways such as farmer trainers and local leaders. The purpose of this study was to investigate the three dissemination pathways and determine their effectiveness as regards improved fallows. This study assumed that farmers were not taking up improved fallows because they lacked knowledge of it, and also that the lack of knowledge was exacerbated by the ineffective pathway used to reach the farmers. The study was conducted in Chadiza, Chipata and Katete districts of Eastern Zambia. Data were collected using questionnaires in 28 villages across the three districts. Included in the sample were 296 small-scale farmers for whom this technology is intended. Additionally, 51 farmer trainers, 15 local leaders and 14 agricultural extension officers were interviewed as disseminators of this technology. Farmers were randomly sampled; local leaders were systematically sampled while a total enumeration was done for farmer trainers and agricultural extension officers present at the time of the interviews. This study found that 92% of the farmers were aware of the technology, with 68% having only known about it between 1998 and early 2000. This was the period when farmer trainers were already working. Farmer trainers were source of initial information to 41% of the farmers and yet they only started working recently. Although 92% of the farmers had heard about improved fallows, only 33% had ever planted some. Ten percent cf the entire population of farmers could be said to have adopted improved fallows because they have planted more than one fallow. Lack of knowledge is therefore not the only reason that farmers were not taking up improved fallows. Farmer trainers were found to currently be a more effective dissemination pathway as they were able to reach more farmers even in areas where agricultural extension officers had not been before. Local leaders have not been involved with disseminating improved fallows. Agricultural extension officers were hampered by lack of resources but were still trying to assist farmers with resource assistance from external institutions such as NGOs. The findings point to a need for participatory extension approaches as well as participatory monitoring and evaluation systems. / AFRIKAANSE OPSOMMING: Agrobosbou-navorsers in Oos-Zambië het braaklandbewerking geïdentifiseer as ingryping in grondvrugbaarheidsprobleme wat ondervind word deur boere wat op klein skaal boer. Die resultaat van eksperimente wat gedoen is as deel van beide proefplaas- en plaasnavorsing sedert 1989 het daarop gewys dat die bewerking van braaklande die agteruitgang van grond kan temper en geleidelik die produktiwiteit daarvan kan verhoog. Navorsers sowel as voorligtingsbeamptes het sedertdien onderneem om braaklandbewerking aan die boeregemeenskap bekend te stel. Navorsers was aanvanklik ten volle afhanklik van die konvensionele landbou-voorligtingsdienste om die verspreiding van tegnologiese kennis onder boere te hanteer. Hierdie verspreidingsproses was egter stadig en die boere het ook te lank geneem om die tegnologie in werking te stel. Aangesien dit vir die navorsers belangrik was dat boere braaklandbewerking so spoedig moontlik begin. het hulle daarop besluit om alternatiewe metodes van kennisverspreiding te gebruik. Hierdie alternatiewe metodes het behels dat inligting versprei is deur opleidingsbeamptes onder boere sowel as deur plaaslike leiers. Die doel van hierdie studie was om die drie kanale wat gebruik is om inligting te versprei, te ondersoek en die effektiwiteit daarvan vas te stel. Hierdie studie het voorveronderstel dat boere nie braaklandbewerking gebruik nie omdat hulle nie oor die nodige kennis beskik het nie, en dat die gebrek aan die nodige kennis veroorsaak en vererger is deur die oneffektiewe kanale wat gebruik is om die inligting onder boere te versprei. Die studie is uitgevoer in die distrikte Chadiza, Chipata en Katete van Oos-Zambië. Data is ingesamel deur die gebruik van vraelyste in 28 dorpe dwarsdeur die drie distrikte. Dié steekproef sluit 296 boere in wat op klein skaal boer en op wie dié tegnologie gemik was. Onderhoude is gevoer met 'n aantal addisionele persone, as verspreiders van tegnologiese kennis, bestaande uit Slopleidingsbeamptes onder boere, 15 tradisionele plaaslike leiers, en 14 landbou-voorligtingsbeamptes. Boere is lukraak getrek vir die steekproef Plaaslike leiers is sistematies getrek, terwyl die totale aantal opleidingsbeamptes en landbou-voorligtingsbeamptes wat teenwoordig was ten tye van die onderhoude, as proefpersone gebruik is. Daar is bevind dat 92% van die boere bewus was van dié tegnologie, waarvan 68% eers tussen 1998 en vroeg 2000 daarvan gehoor het. Dit was die periode waarin opleidingsbeamptes alreeds onder die boere werksaam was. Opleidingsbeamptes was vir 41% van die boere die bron van die oorspronklike inligting, en tog het hulle onlangs eers onder die boere begin werk. Alhoewel 92% van die boere al van die bewerking van braaklande gehoor het, het slegs 33% al ooit braaklande aangelê. Daar kan gesê word dat tien persent van die totale boerebevolking braaklandbewerking prakties toegepas het omdat hulle meer as een bewerkte braakland aangelê het. Die gebrek aan kennis is daarom nie die enigste rede vir boere se traagheid om die praktyk van braaklandbewerking te aanvaar nie. Opleidingsbeamptes blyk tans die mees effektiewe verspreiders van inligting onder boere te wees aangesien hulle daartoe in staat was om meer boere te bereik, selfs in gebiede waar landbou-voorligtingsbeamptes nog nooit voorheen was nie. Plaaslike leiers was nie betrokke by die verspreiding van braaklandbewerking me. Landbou voorligtingsbeamptes is gekniehalter deur'n gebrek aan hulpbronne, maar het steeds probeer om boere by te staan met behulp van bystand wat verleen is deur eksterne instellings soos Nie-Regeringsorganisasies (NRO's). Dié bevindinge dui op 'n behoefte aan voorligtingsbenaderings sowel as monitering- en evalueringstelsels wat deelnamegeoriënteer is.

Plants are the major source of food or energy required to sustain life on the planet, but humans are grappling with the deteriorating conditions of natural ecosystems such as compositional change, desertification, invasive plants and soil erosion. In the face of global climate change and growing demands for agricultural productivity, future pressures on grassland ecosystems will intensify, therefore sustainable utilization of all plant resources is of vital importance to enhance food security within the limits of good conservation. The semi-arid grasslands of southern Africa represent major grassland resources for grazing. Herbage production in these areas is determined not only by water and nutrient availability, but also by controlled and uncontrolled fires. Since fire is regarded as a natural factor in savannas, it is essential to develop a deeper understanding of the role of fire in community structure and function for the development of appropriate burning regimes. A study was conducted in the Eastern Cape of South Africa where the rural communities are faced with the challenges of rangeland degradation in the form of encroachment by unacceptable bush, karroid, macchia and less desirable grass species, as well as soil erosion. The main objective of this thesis was to investigate the roles of competition and disturbance regimes (fire and simulated non-selective grazing) on species composition, habitat productivity and the performances of selected species from this semi-arid savanna. Long-term effects of burning frequency on herbaceous species composition, Leaf Area Index (LAI), Photosynthetically Active Radiation (PAR) within the herbaceous canopy, biomass production and soil chemical properties were investigated. These studies were conducted on a fire trial set up in 1980 at the University of Fort Hare research farm in the Eastern Cape, South Africa. The treatments comprise an annual, biennial, triennial, quadrennial, sexennial and no burn control, all replicated twice in a Complete Randomized Design. The data from the trial collected between 1980 and 2008 were used to determine compositional variation for herbaceous species using the Non-metric Multidimensional Scaling and Bray-Curtis Dissimilarity tests. The PAR ceptometer was used to determine LAI and intercepted PAR, while random samples were harvested from 1m² quadrats from each plot. Soil samples were taken at four depths (0-2 cm; 2-4 cm; 4-6 cm and 6-8 cm) from each plot and analyzed for pH, Ca, K, P, total C and total N. The Resin-Bag technique was used to determine nitrogen mineralization. Burning frequency caused significant variation in herbaceous species composition over time. The species were distributed along gradients of increasing burning frequency, and these responses were in three categories: Those that increased with burning frequency such as Themeda triandra; those that decreased with burning frequency such as Melica decumbens, and those that showed little response such as Panicum maximum. The three-year burn resulted in the highest compositional variation, light interception, Leaf Area Index, aboveground biomass production, while the annual, biennial and no burn treatments resulted in the lowest. The fact that infrequent burning resulted in higher species variation, improved habitat productivity due to increased leaf area for light interception shows that appropriate use of fire can maintain a more diverse and productive savanna system. Burning frequency had significant effects on the soil properties, while soil depth did not show any significance. Frequent burning increased soil pH, K, Ca, and Na, but reduced C, N, P and N mineralization. There was a negative correlation between burning frequency and N mineralization, but no correlation existed between N mineralization and total N, total C or the C:N ratio. These results imply that frequent burning can cause nutrient losses and a greater nutrient limitation to plants in the long-term, especially soil C and N loss from combustion of organic material in the soil top layer. The ability of shade-tolerant plants to persist under shade and regular defoliation such as in burnt and grazed systems may be of greater importance for long-term productivity and sustainability of forage crops. It is therefore imperative to explore the mechanisms by which some species were favoured by frequent burning which created low shade conditions, while others were favoured by high shade conditions where burning is infrequent or absent. A pot experiment was conducted to investigate the shade tolerances of seven grass species that were abundant in the long-term fire trial. The test species were Cymbopogon plurinodis, Digitaria eriantha, Eragrostis curvula, Melica decumbens, Panicum maximum, Sporobolus fimbriatus and Themeda triandra. Individual grass tillers of each species were collected from the natural vegetation, propagated in separate seedling trays and transplanted into individual pots, and were grown under five shading treatments: full sun (0 % shading), 55 %; 70 %; 85 % and 93 % shading respectively. Shading significantly reduced the dry matter production of all the species. Biomass production of all the species decreased linearly to varying degrees with an increase in shade intensity. Digitaria eriantha and Eragrostis curvula were most adversely affected by shading, hence are classified as shade intolerant, while Melica decumbens was the least affected by shading, and is hence classified as shade tolerant. Cymbopogon plurinodis, Panicum maximum, Sporobolus fimbriatus and Themeda triandra are classified as moderately shade-tolerant. From the results it was apparent that some species could perform optimally in partial shade than in full sunlight, and these results lead to a conclusion that for satisfactory natural regeneration and seedling growth of this savanna vegetation would require a gap large enough to provide at least 30 % of ambient light. Investigating patterns in competitive effects and responses of species in these communities may not only explain the abundance of each species, but may also provide insight into the nature of forces that affect the structure and function of that community. Since fire, herbivory and soil nutrients are natural drivers of savanna community structure and function, their influence on competitive interactions of selected species were investigated. Two experiments were conducted to investigate the competitive effects and responses of eight selected common species in the area. The test species (phytometers) included one woody shrub, Acacia karroo and seven grass species namely: Cymbopogon plurinodis, Digitaria eriantha, Eragrostis curvula, Melica decumbens, Panicum maximum, Sporobolus fimbriatus and Themeda triandra. In an outdoor plot experiment the responses of the phytometers to competition from neighbours (0; 2 and eight neighbours respectively), fertility (fertilized, unfertilized) and clipping (clipping, no clipping) were investigated. The second comprised a pot experiment where the competitive effects of the species were investigated. Each species was grown under 3 levels of fertility (0 %; 50 % and 100 % Hoagland‘s solution) and clipping (clipping, no clipping) in pots filled with fine river sand and 4 neighbours. Competition intensity, soil fertility and clipping had significant effects on the biomass production of the phytometer species. Acacia karroo and Melica decumbens, exhibited the weakest competitive effects and responses, and incurred the highest mortalities after clipping and with 8 neighbours. Digitaria eriantha and Panicum maximum exhibited the strongest competitive effects and responses, especially in high fertility, and experienced the lowest mortalities. T.triandra exhibited stronger competitive effect after clipping in low fertility, while A. karroo and C. plurinodis exhibited stronger competitive effects in moderate (50 %) fertility. Cymbopogon plurinodis, Eragrostis curvula and Sporobolus fimbriatus ranked between these two extreme groups in terms of competitive effects and responses. Relative Competitive Interaction increased with soil fertility and number of neighbours in the absence of clipping. These results indicate that in general, taller or broad-leaved grass species outgrow the shorter ones, and this gives them a competitive advantage over light and soil resources. One of the range management objectives in the False Thornveld of the Eastern Cape is to promote the abundance of Themeda triandra, which is of high forage value and an indicator of rangeland that is in good condition. The general situation under livestock farming conditions in this area is that if the grass sward is optimally grazed and rested then there is a great potential for Themeda triandra to dominate.The results of the competition experiments indicated that the species exhibits strong competitive interaction, and also exhibited stronger competitive effect after clipping in low fertility. These results imply that it has a low response and a high effect, an attribute that would enhance its performance if it is moderately grazed or the area is burnt. The species is also moderately shade tolerant, and this may explain why it thrives in burnt and moderately grazed areas. These studies have demonstrated the important role that competition and disturbance in the form of fire and herbivory play in the maintenance of this savanna grassland. Through natural selection species are able to occupy different niches in the same area and coexist in a heterogeneous environment and minimize their chances of extinction. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

This study seeks to examine and assess the effectiveness of the Eastern Partnership Policy (EaP) of the European Union. Beside introduction of positive novelties of the Eastern Partnership, this paper gives a premium attention to scrutinize the possible limitations and shortfalls of EaP. Hence, the study aims to analyze some internal and external factors that complicate the effective functioning of the EaP. The inconsistency of the EU policy structure, the role of Russia and its Eurasian Economic Union (EaEU) in EAP, the ambivalent policy of some Member States (Germany and Italy are examined) toward the EaP, unconsidered discrepancy of eastern partners are analyzed and considered as prime reasons of ineffectiveness. In addition, examined case studies of Ukraine and Azerbaijan reveal that the EU's commitment to their "shared values" are controversial. This paper presents that the EU should find a balance between its economic/energy interests and normative values vis-a-vis Eastern Partners in order to fill the gap between its goals and achievements.

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The influence of streambank location and timing of herbivory on success of planted Booth's willow (Salix boothii Dorn) cuttings along a Rosgen C5-type stream in an eastern Oregon meadow was determined. Willow cuttings were planted on two morphological locations (i.e. point bar and floodplain) in May of 2002 and 2003. Gravimetric soil moisture and depth to water table data were collected periodically on each planting location during the growing season, May through September, in both years. Three grazing treatments, early season, late season, and none (control) were conducted. Percent survival, leader density, and number of browsed leaders of willows were recorded prior to and after each grazing treatment, as well as stubble height of forage species. Simple linear regression was used to determine if a relationship between residual stubble height and percent willow browse existed. Multiple linear regression was used in an attempt to develop a predictive equation for percent browse based on pre-grazing stubble and willow heights. It was hypothesized that depth to water table and percent soil moisture throughout the growing season would significantly influence willow survival and growth; that survival would be higher on point bar locations; and that willows would be browsed at different intensities according to season of grazing. Soil moisture content at point bar locations was greater than that of floodplain locations for the majority of the growing season in both years. In 2003, groundwater levels were higher on point bar than floodplain locations from May through September. Willow survival was higher for point bar locations than floodplain locations, in both years, regardless of grazing treatment. Willows were browsed more intensively later in the growing season. Results from the simple linear regression suggest that percent browse of willows was related to the residual stubble height, but did not explain the variability observed. An attempt to develop a predictive equation, i.e., expected browse based on pre-grazing stubble height, was made, however no apparent relationship between the willow height, stubble height, and percent browse was found. Grazing treatment did influence willow survival; survival on floodplain locations within the late grazing treatment was less than that of the ungrazed floodplain locations. Our results suggest that planting willows in locations where the planting depth remains within 40 cm of the groundwater depth will increase planting success. Protection from grazing for at least the first year of growth is recommended for optimum planting survival; grazing early in the season is more favorable to survival than grazing later in the season. / Graduation date: 2004