Thesis (MSc)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: The agricultural sector in South Africa relies heavily on the use of pesticides to protect crops against pest organisms. Pesticides can affect non-target organisms such as the meso- and macrofauna in the soil detrimentally. Since these organisms play an important role in the processes of mineralization and decomposition in the soil and contribute to soil fertility, it is important that they are protected. A large amount of published literature exists on the biological importance of soil meso- and macrofauna and the effects that various agricultural practices have on them. The main aim of this study was to investigate the influence of agricultural practices on the abundance and diversity of meso- and macrofauna in different vineyard soils. A comparative study was conducted of an organically managed, conventionally managed and an uncultivated control soil. A secondary aim was to determine the effect of these agricultural management practices on the biological activity of these animals. Soil samples were taken, from which mesofauna (Collembola and Acari) were extracted with a modified Tullgren extractor, identified and counted. Earthworms were extracted from the soil using hand sorting methods. Soil parameters such as pH, water holding capacity, organic matter content, soil texture and soil respiration were determined. Bait lamina and litter-bags were also used to help determine the biological activity within the soil. The mesofauna diversity was quantified using the Shannon Weiner diversity index, as well as a diversity index described by Cancela da Fonseca and Sarkar (1996). Differences in abundance of both the meso-and macrofauna were statistically measured using ANOVA's. Biological activity results were also interpreted using ANOV A's. Results indicate that the abundance of the meso fauna was the highest at the organically treated vineyard soil and lowest in the conventionally managed soil where pesticide application took place. The earthworms also showed the same trend as the mesofauna, but were much more influenced by seasonal changes. Biological activity, according to the bait lamina and the litter-bag results, was higher in both the conventionally and organically managed soils than in the control, but no statistical significant differences were found between the two experimental soils. The soil respiration (C02-flux), also indicating biological activity, was highest in the organically treated soil and lowest in the conventionally treated soil. The different sampling techniques used gave variable results and although the organically managed soil proved to have higher abundances of both meso- and macrofauna, the biological activity did not show the same trends. In conclusion the data did not give enough evidence as to whether organic management practices were more beneficial than conventional management practices for the maintenance of soil biodiversity. / AFRIKAANSE OPSOMMING: Die Suid Afrikaanse Landbousektor steun hewig op die gebruik van verskillende chemiese pestisiede om oeste teen pes organismes te beskerm. Pestisiede kon ook verskeie ander nie-teikenorganismes soos die meso- en makrofauna in die grond negatief affekteer. Hierdie organismes behoort beskerm te word omdat hulle 'n belangrike rol speel in grondprosesse soos mineralisering, en die afbreek van organiese materiaal. Hierdie organismes dra ook by tot die vrugbaarheid van die grond. Daar is heelwat gepubliseerde literatuur beskikbaar wat verband hou met die biologiese belangrikheid van grond meso- en makrofauna en die effekte wat verskeie landbou behandelings op hulle het. Die primêre doel van hierdie studie was om vas te stel watter invloed konvensionele landboupraktyke op die hoeveelheid en diversiteit van meso- en makrofauna in verskillende wingerdgronde het. 'n Vergelykende studie is gedoen om wingerdgronde wat konvensioneel en organies behandel is sowel as 'n onbehandelde kontrolegrond met natuurlike plantegroei met mekaar te vergelyk. 'n Sekondêre doel van hierdie studie was ook om die effek van die verskillende boerderymetodes op die biologiese akitiwiteit in die grond te ondersoek. Grondmonsters is geneem, waaruit die meso fauna (Collembola en Acari) deur middel van 'n aangepaste Tullgren ekstraktor ge-ekstraheer, geïdentifiseer en getel. Die erdwurms is deur middel van handsorteringsmetodes versamel. Die volgende grond parameters is gemeet: pH, waterhouvermoë, organiese materiaal inhoud, grondtekstuur en grondrespirasie. "Bait lamina" en "litter bags" is ook gebruik om biologiese aktiwiteit in die grond te bepaal. Die diversiteit van mesofauna is bepaal met die Shannon Weiner diversiteitsindeks, as ook 'n diversiteitsindeks wat deur Cancela da Fonseca en Sarkar (1996) ontwikkel is. Die resultate van beide die meso- en makrofauna hoeveelhede in die verskillende wingerdgronde is met mekaar vergelyk deur van ANOV A's gebruik te maak. Die resultate van die biologiese aktiwiteit is ook deur middel van ANOVO's statisties met mekaar vergelyk. Die resultate het aangetoon dat die hoeveelheid mesofauna die hoogste in die organies behandelde grond en die laagste in konvensionele grond was. Die erdwurms het dieselfde patroon as die mesofauna getoon, maar is baie meer deur seisoenale faktore geaffekteer, bv. reënval. Volgens die resultate van die "bait lamina" en die "litter bags" was die biologiese aktiwiteit in die grond hoër in beide die eksperimentele grond as in die kontrolegrond. Die grondrespirasie (C02-puIs) was hoër in die kontrolegrond as in die ander eksperimentele gronde. Daar was groot variasie tussen die resultate wat met die verskillende tegnieke verkry is en alhoewel die organiese perseel hoër hoeveelhede van beide meso- en makrofauna gehad het, het die biologiese aktiwiteit nie dieselfde tendens gewys nie. Vanuit die data wat verkry is kon daar dus nie met sekerheid afgelei word dat organiese boerderymetodes beter vir die biodiversiteit van gronde,soos hier gemeet, is as konvensionele boerderymetodes nie.

CAPES / A comunidade da fauna edáfica tropical é diversa, porém com escassas informações taxonômicas em projetos de restauração. Esses organismos são indicativos da qualidade ambiental, sendo o seu monitoramento essencial para uma análise ecossistêmica. O objetivo do presente trabalho foi avaliar o papel da fauna edáfica como bioindicadora da qualidade ambiental em áreas sob diferentes tecnologias de restauração florestal. O trabalho foi conduzido na estação experimental da Universidade Tecnológica Federal do Paraná, Dois Vizinhos, Paraná. Os tratamentos avaliados foram: Restauração Passiva (RP; regeneração natural); Nucleação (NC; conjunto de técnicas recobrindo 1/3 da área); e Plantio de Alta Diversidade (PAD; plantio de árvores em área total). Adjacente ao experimento, a floresta secundária em estágio médio de regeneração (FL), serviu como área referência. O delineamento experimental foi em blocos ao acaso, com quatro repetições e três subamostras por parcela. As famílias de Coleoptera foram coletadas através de armadilhas Pitfall (04/2011) e a mesofauna e colêmbolos, foram extraídos em funis de Berlese-Tüllgren (12/2015). Foram amostrados 866 besouros em 16 famílias, sendo os herbívoros mais abundantes nos tratamentos de restauração e os não herbívoros na floresta. A RP e a FL foram os tratamentos mais diversos. Na Análise de Similaridade (ANOSIM), houve diferenças entre as tecnologias de restauração e a FL e, entre RP e PAD, sendo essas informações corroboradas pela Análise de Componentes Principais (ACP). Para a mesofauna, foram coletados 15.367 indivíduos e a riqueza e abundância de organismos foi superior na FL e a RP apresentou a comunidade mais uniforme. A ANOSIM apenas não diferenciou a interação entre RP e PAD, os demais tratamentos avaliados apresentam uma comunidade edáfica diferenciada entre si. Os grupos Hemiptera, Haplotaxida, Trichoptera, Acariformes, Diplopoda e Pseudoscorpiones foram os principais responsáveis pela distinção das tecnologias através da análise de porcentagem de similaridade (SIMPER). Na ACP, a floresta se separou das tecnologias, ficando associada aos Acariformes, Diplopoda, Diplura, Hemiptera e Pseudoscorpiones. Foram amostrados 2.429 Colêmbolos em 35 morfotipos, sendo a riqueza média superior na FL e a abundância superior na FL e PAD. O índice de diversidade de Shannon encontrados seguiu um gradiente de intervenção antrópica (FL>RP>NC>PAD). A ANOSIM encontrou dissimilaridades entre as três tecnologias de restauração e a floresta, que se separou das demais na ACP. A fauna edáfica foi um eficiente indicador da qualidade ambiental, diferenciando as tecnologias em processo inicial de restauração da floresta e já mostrando algumas particularidades entre as tecnologias em si. Para efetivar seu papel bioindicadores, o monitoramento deve ser realizado a longo prazo, identificando os grupos chave em áreas em áreas em processo de restauração florestal. / The community of tropical edaphic fauna is diverse, but with scarce taxonomic information on restoration projects. These organisms are indicative of environmental quality, and their monitoring is essential for an ecosystem analysis. The objective of this work was to evaluate the role of soil fauna as a bioindicator of environmental quality in areas under different forest restoration technologies. The work was conducted at the experimental station of the Universidade Tecnológica Federal do Paraná, Dois Vizinhos, Paraná. The treatments evaluated were: Passive Restoration (RP, natural regeneration); Nucleation (NC, set of techniques covering 1/3 of the area); And High Diversity Planting (PAD, planting of trees in total area). Adjacent to the experiment, the secondary forest in the middle stage of regeneration (FL) served as a reference area. The experimental design was in randomized blocks, with four replications and three sub - samples per plot. Coleoptera families were collected through Pitfall traps (04/2011) and the mesofauna and Collembola were extracted in Berlese-Tüllgren funnels (12/2015). A total of 866 beetles were sampled in 16 families, with herbivores being most abundant in restoration treatments and non - herbivores in the forest. RP and FL were the most diverse treatments. In the Analysis of Similarity (ANOSIM), there were differences between the restoration technologies and the FL and, between RP and PAD, being this information corroborated by the Principal Component Analysis (PCA). For the mesofauna, 15,367 individuals were collected and the richness and abundance of organisms was higher in FL and RP presented the most uniform community. ANOSIM only did not differentiate the interaction between RP and PAD, the other evaluated treatments present a differentiated edaphic community among them. The groups Hemiptera, Haplotaxida, Trichoptera, Acariformes, Diplopoda and Pseudoscorpiones were the main responsible for the differentiation of the technologies through the similarity percentage analysis (SIMPER). In the ACP, the forest separated from the technologies, being associated with the Acariformes, Diplopoda, Diplura, Hemiptera and Pseudoscorpiones. 2,429 Collembola were sampled in 35 morphotypes, with the upper average richness in FL and the superior abundance in FL and PAD. The diversity index of Shannon found followed a gradient of anthropic intervention (FL> RP> NC> PAD). ANOSIM found dissimilarities between the three restoration technologies and the forest, which separated from the others in the ACP. The edaphic fauna was an efficient indicator of the environmental quality, differentiating the technologies in the initial process of forest restoration and already showing some peculiarities among the technologies themselves. In order to realize its role bioindicators, the monitoring should be carried out in the long term, identifying the key groups in areas in areas in the process of forest restoration.

CAPES / A comunidade da fauna edáfica tropical é diversa, porém com escassas informações taxonômicas em projetos de restauração. Esses organismos são indicativos da qualidade ambiental, sendo o seu monitoramento essencial para uma análise ecossistêmica. O objetivo do presente trabalho foi avaliar o papel da fauna edáfica como bioindicadora da qualidade ambiental em áreas sob diferentes tecnologias de restauração florestal. O trabalho foi conduzido na estação experimental da Universidade Tecnológica Federal do Paraná, Dois Vizinhos, Paraná. Os tratamentos avaliados foram: Restauração Passiva (RP; regeneração natural); Nucleação (NC; conjunto de técnicas recobrindo 1/3 da área); e Plantio de Alta Diversidade (PAD; plantio de árvores em área total). Adjacente ao experimento, a floresta secundária em estágio médio de regeneração (FL), serviu como área referência. O delineamento experimental foi em blocos ao acaso, com quatro repetições e três subamostras por parcela. As famílias de Coleoptera foram coletadas através de armadilhas Pitfall (04/2011) e a mesofauna e colêmbolos, foram extraídos em funis de Berlese-Tüllgren (12/2015). Foram amostrados 866 besouros em 16 famílias, sendo os herbívoros mais abundantes nos tratamentos de restauração e os não herbívoros na floresta. A RP e a FL foram os tratamentos mais diversos. Na Análise de Similaridade (ANOSIM), houve diferenças entre as tecnologias de restauração e a FL e, entre RP e PAD, sendo essas informações corroboradas pela Análise de Componentes Principais (ACP). Para a mesofauna, foram coletados 15.367 indivíduos e a riqueza e abundância de organismos foi superior na FL e a RP apresentou a comunidade mais uniforme. A ANOSIM apenas não diferenciou a interação entre RP e PAD, os demais tratamentos avaliados apresentam uma comunidade edáfica diferenciada entre si. Os grupos Hemiptera, Haplotaxida, Trichoptera, Acariformes, Diplopoda e Pseudoscorpiones foram os principais responsáveis pela distinção das tecnologias através da análise de porcentagem de similaridade (SIMPER). Na ACP, a floresta se separou das tecnologias, ficando associada aos Acariformes, Diplopoda, Diplura, Hemiptera e Pseudoscorpiones. Foram amostrados 2.429 Colêmbolos em 35 morfotipos, sendo a riqueza média superior na FL e a abundância superior na FL e PAD. O índice de diversidade de Shannon encontrados seguiu um gradiente de intervenção antrópica (FL>RP>NC>PAD). A ANOSIM encontrou dissimilaridades entre as três tecnologias de restauração e a floresta, que se separou das demais na ACP. A fauna edáfica foi um eficiente indicador da qualidade ambiental, diferenciando as tecnologias em processo inicial de restauração da floresta e já mostrando algumas particularidades entre as tecnologias em si. Para efetivar seu papel bioindicadores, o monitoramento deve ser realizado a longo prazo, identificando os grupos chave em áreas em áreas em processo de restauração florestal. / The community of tropical edaphic fauna is diverse, but with scarce taxonomic information on restoration projects. These organisms are indicative of environmental quality, and their monitoring is essential for an ecosystem analysis. The objective of this work was to evaluate the role of soil fauna as a bioindicator of environmental quality in areas under different forest restoration technologies. The work was conducted at the experimental station of the Universidade Tecnológica Federal do Paraná, Dois Vizinhos, Paraná. The treatments evaluated were: Passive Restoration (RP, natural regeneration); Nucleation (NC, set of techniques covering 1/3 of the area); And High Diversity Planting (PAD, planting of trees in total area). Adjacent to the experiment, the secondary forest in the middle stage of regeneration (FL) served as a reference area. The experimental design was in randomized blocks, with four replications and three sub - samples per plot. Coleoptera families were collected through Pitfall traps (04/2011) and the mesofauna and Collembola were extracted in Berlese-Tüllgren funnels (12/2015). A total of 866 beetles were sampled in 16 families, with herbivores being most abundant in restoration treatments and non - herbivores in the forest. RP and FL were the most diverse treatments. In the Analysis of Similarity (ANOSIM), there were differences between the restoration technologies and the FL and, between RP and PAD, being this information corroborated by the Principal Component Analysis (PCA). For the mesofauna, 15,367 individuals were collected and the richness and abundance of organisms was higher in FL and RP presented the most uniform community. ANOSIM only did not differentiate the interaction between RP and PAD, the other evaluated treatments present a differentiated edaphic community among them. The groups Hemiptera, Haplotaxida, Trichoptera, Acariformes, Diplopoda and Pseudoscorpiones were the main responsible for the differentiation of the technologies through the similarity percentage analysis (SIMPER). In the ACP, the forest separated from the technologies, being associated with the Acariformes, Diplopoda, Diplura, Hemiptera and Pseudoscorpiones. 2,429 Collembola were sampled in 35 morphotypes, with the upper average richness in FL and the superior abundance in FL and PAD. The diversity index of Shannon found followed a gradient of anthropic intervention (FL> RP> NC> PAD). ANOSIM found dissimilarities between the three restoration technologies and the forest, which separated from the others in the ACP. The edaphic fauna was an efficient indicator of the environmental quality, differentiating the technologies in the initial process of forest restoration and already showing some peculiarities among the technologies themselves. In order to realize its role bioindicators, the monitoring should be carried out in the long term, identifying the key groups in areas in areas in the process of forest restoration.

Orientador: Carlos Roberto Spindola / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-15T19:11:40Z (GMT). No. of bitstreams: 1 Catanozi_Gerson_D.pdf: 11539513 bytes, checksum: ab8020b1e51d03c4b15a4b840fa0132c (MD5) Previous issue date: 2018-08-15T16:11:29Z / Resumo: A biodiversidade no Brasil é considerada uma das maiores do planeta. Parte significativa desta permanece desconhecida. Nesse caso, encontra-se a fauna de solo. Além da importância ecológica, esses organismos têm se revelado fundamentais para o bom funcionamento do sistema edáfico. O objetivo deste trabalho é analisar e identificar grupos taxonômicos da macrofauna de solo e estabelecer os respectivos índices ecológicos em: áreas florestais conservadas e em recuperação da degradação por mineração; e áreas sob manejo agrícola - biodinâmico e tradicional. Para tanto, foram realizadas coletas utilizando-se os métodos - Pitfall traps e TSBF. Os animais coletados foram identificados em grandes grupos taxonômicos e contabilizados para se obter densidades, riquezas e índices ecológicos. Os resultados indicam que a densidade de grupo, associada à riqueza e índices ecológicos, contribui de forma importante para um entendimento integrado. Os solos em processo de recuperação apresentaram valores que diferiram entre si, principalmente nas camadas mais superficiais. Pastos com braquiária podem ser diferentes entre si com relação à macrofauna de solo, principalmente em favor do manejo biodinâmico com maior diversidade de espécies vegetais. Finalmente, modelos matemáticos das densidades podem contribuir com a análise ou previsão das condições do solo. Porém, estudos complementares são necessários, reforçando a possibilidade de tornar viável o uso de organismos da macrofauna de solo como bioindicadores ambientais / Abstract: Biodiversity in Brazil is considered one of the greatest on the planet. Important part of it has kept unknown and many species have been extinguished quite before scientifically identified, mainly because of the small size of those organisms or the restricted access to them. That may be particularly the case of soil fauna. Besides their ecological importance, those organisms have played fundamental role for a good work of edaphic system. The objective of this work is to analyze and identify taxonomic groups of soil macrofauna, establishing the respective ecological indexes at: conserved rainforest and in recovery process from degradation by tin mining areas; and areas under biodynamic system and conventional management. In order to that, collects were taken by using two methods - Pitfall traps and TSBF. The collected animals were identified into broad taxonomic and counted to determine their densities, richness and ecological indexes. The general results suggest that the density of each animal taxonomic unit, associated to richness of groups and ecological indexes, supplies in an important way for a global understanding. Soils in different recovery process showed different results, mainly within the superficial layers. Biodinamyc managed pastures with Brachiaria sp may be different between each other about epigeic and edaphic macrofauna, mostly where greater diversity of consorted plant species are present, even in conventional management approach. Finally, mathematical models for density may contribute to analyze and forecast the soil conditions. Nevertheless, additional studies are necessary in order to make possible the use of soil macrofauna as environmental bioindicators / Doutorado / Análise Ambiental e Dinâmica Territorial / Doutor em Ciências

Thesis (MSc)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: Food demands for the ever-increasing human population is increasing the pressure on the agricultural sector to produce more food. In order to satisfy these demands, farmers are turning to chemical biocides for the control of pest species to produce greater crop yields. All pesticides must be toxic or poisonous to the target species they intend to control. Unfortunately, most pesticides are toxic or poisonous to non-target organisms as well, with detrimental effects on their health. Organic farming was developed to enhance the overall health of the farm's natural soilmicrobe- plant-animal biodiversity. No synthetic fertilisers and/or pesticides are used when farming organically. Life in the soil consists of intricate food webs and interactions between the soil dwelling invertebrates. The soil-organisms are divided into three main groups, viz., Micro-organisms (e.g. protozoa, bacteria and fungi) mesofauna (nematodes, Collembola and Acari) and macro-fauna (e.g. millipedes, isopods, insects, molluscs and earthworms). The invertebrates are very susceptible to chemical contamination by chemical biocides in natural and agro-ecosystems. The soil invertebrate communities are responsible for the decomposition of organic material in soil, thereby remineralising the soil. The decomposition processes start with comminution of the large pieces of organic material by meso- and macro-fauna and ends with the micro-fauna and microbial organisms that complete these processes by returning the nutrients in an inorganic form to the soil. The aim of this study was to investigate whether, and to what extent the soil organisms are influenced by different management practices viz., organic management practices versus conventional management practices. A vineyard on the farm Plaisir de Merle, in Simondium, Western Cape was used for the present study. One half of a one hectare vineyard was managed organically and the other half conventionally. Within each vineyard block six different treatments were performed. Three of the treatments were strictly organic and the other three were strictly conventional. Four replicates of each management treatment were performed. The bait-lamina technique was used to assess the feeding activity of the soil organisms exposed to the different management treatments. In addition to the bait-lamina trials in the vineyard itself, bait-lamina tests were performed in microcosm studies with soil from the organically and conventionally managed vineyard blocks under controlled conditions. In order to assess the impact of the various pesticides that are used in the vineyards in the conventional way, on the soil fauna, standard acute toxicity tests and behavioural tests were performed on Eisenia fetida, the compost worm. The bait-lamina tests in the vineyard revealed that the moisture content of the soil plays an important role in the biological activity of soil fauna. The different management treatments did affect the biological activity of the soil fauna, but seasonal changes also proved to be one of the important factors governing biological processes in the soil. The acute toxicity tests showed that the active ingredients (mancozeb, penconazole and trifloxystrobin) of three of the pesticides that were tested in this study, had negatively affected E. fetida at their recommended application concentrations. The remaining two pesticides' active ingredients (glyphosate and N-acetyl salicylic acid) did not affect the earthworms negatively at the recommended application concentrations. The preference behavioural trials showed that E. fetida could detect and avoid contaminated substrates at the LCso-concentrations of the different pesticides. All the earthworms were influenced positively in the preference behaviour experiments. Because of certain limitations of the bait-lamina technique, it was difficult to formulate conclusions on what happens in the soil. A possible explanation for the differences in feeding activity of soil fauna could be attributed to the migration of the soil fauna to more habitable soil horizons during the dry summer conditions, when most of the pesticides are applied. The ecological relevance of the acute toxicity tests conducted need to be investigated further. It is clear that the acute toxicity tests provided important information that should be considered, but care should be taken and the necessary safety factors be determined and considered when doing risk assessment studies. The results of the preference behaviour studies showed that for certain pesticides E. fetida can be a sensitive bioindicator of acute and/or sub-acute lethal toxicity testing but this might not necessarily be the case for other pesticides. The goal of doing laboratory studies is to gain as much information to make reliable extrapolations to field situations from laboratory data. Laboratory-to-field extrapolations are very complicated because of the physico-chemical composition of soil, the unpredictable way pesticides behave within soil and the reaction of soil organisms to the soil and to the chemical biocides that are used. Further studies need to be done in order to fully understand to what extent the soil fauna were affected by the different management practices applied to the vineyard at Plaisir de Merle. / AFRIKAANSE OPSOMMING: Voedsel aanvraag vir die toenemende menslike bevolking plaas groot druk op die landbou sektor om meer kos te produseer. Om aan die voedsel eise te voldoen, gebruik boere al meer chemiese biosiede om pesspesies te bestry. Alle pestisiede moet toksies of giftig wees vir die teiken organisme waarvoor dit bestem is. Ongelukkig is die meeste pestisiede ook toksies of giftig vir nie-teiken organismes, wat tot nadelige effekte op hul gesonheid kan lei. Organiese boerdery is ontwikkel om die algehele gesondheid van die plaas se natuurlike grond-mikrobe-plant-dier biodiversiteit te bevorder. Geen sintetiese bemestingstowwe en/of pestisiede mag gebruik word wanneer daar organies geboer word nie. Die lewe in die grond bestaan uit ingewikkelde voedselwebbe en interaksies tussen die grondlewende invertebrate. Die grond invertebrate word verdeel in drie hoof groepe, nl. mikro-organismes (bv. Protozoa, bakterieë en fungi) meso fauna (Nematoda, Collembole en Acari) en makrofauna (bv. Millipoda, Isopoda, Insecta, Mollusca en erdwurms). Die Invertebrata is die mees vatbaarste vir chemiese kontaminasie deur chemiese biosiedes in natuurlike en landbou ekosisteme. Die grond invertebraat gemeenskappe is verantwoordelik vir die afbreek van alle organiese materiaal in die grond en dus vir remineralisering van die grond. Die afbreekproses begin by die komminusie van groter stukke organiese materiaal deur die meso- en makrofauna en eindig met die mikrofauna en mikrobes wat die prosesse voltooi deur die nutriente terug te plaas in die vorm van anorganiese produkte in die grond. Die doel van hierdie studie was om te ondersoek of, en tot watter mate, grond organismes geraak word deur verskillende grondbestuurspraktyke, nl. Organiese grondbestuurspraktyke teenoor die konvensionele grondbestuurspraktyke. 'n Wingerd op die plaas Plaisir de Merle, in Simondium, Wes-Kaap, was gebruik vir die huidige studie. Een helfte van 'n een hektaar wingerd is organies bestuur en die ander helfte is op die konvensionele manier bestuur. Op elk van die twee wingerd blokke is ses verskillende behandelings toegepas. Drie van die behandelings was streng organies en die ander drie was streng konvensioneel van aard. Vier replikate van elke behandeling is toegepas op elk van die twee wingerdblokke. Die bait-lamina metode is gebruik om die voedingsaktiwiteit van die grond organismes te asses seer. As toevoeging tot die bait-lamina proewe in die wingerd self, is bait-lamina toetse ook in mikro-kosmosse in die laboratorium gedoen met grond afkomstig vanaf die twee wingerdblokke. Om die impak van die verskillende pestisiede op die grondorganismes te ondersoek, is standaard akute toksisteitstoestse en gedragstoetse uitgevoer met die komposerdwurm, Eisenia fetida. Die bait-lamina resultate in die wingerd het getoon dat die voginhoud van die grond die belangrikste rol speel wat die biologiese aktiwiteit van die grondorganismes beïnvloed. Die verskillende behandelings het die biologiese aktiwiteit van die grond fauna geaffekteer, maar seisoenale veranderings is ook uitgesonder as een van die bepalende faktore wat die biologiese prosesse in die grond stuur. Die akute toksisiteitstoetse het getoon dat die aktiewe bestandeie van drie van die pestisiede (mancozeb, penconazole en trifloxystrobin), E. fetida negatief beïnvloed het teen die aanbeveelde konsentrasies wat toegedien is. Die aktiewe bestandeie van die ander twee pestiede (glyphosate en N-asetiel sallisiel suur) het nie die erdwurms nadelig beïnvloed teen die aanbeveelde konsentrasies wat toegedien is nie. Die gedragsproewe het getoon dat E. fetida die LCso-konsentrasies van al die verskillende pestisiede kan waarneem en vermy. Al die erdwurms is positief beïnvloed in die gedragseksperimente met die verskillende pestisiede. Omdat die bait-laminametode sekere beperkings het, was dit moeilik om tot gevolgtrekkings te kom oor wat presies in die grond gebeur. 'n Moontlike verklaring vir die verskillende voedingsaktiwiteite van die grond fauna kan toegereken word aan die migrasie van die grondorganismes na meer leefbare grondhorisonne gedurende die droë somer toestande, wat toevallig met die spuit van die meeste pestisiede ooreenstem. Die ekologiese relevansie van die akute toksisiteitstoetse wat uitgevoer is, moet meer deeglik ondersoek word. Die belangrikheid van die akute toksisteitstoetse is duidelik en het waardevolle informasie gelewer, maar sorg moet geneem word, en die nodige veiligheids faktore moet bepaal word en in ag geneem word, wanneer riskobepalingstudies gedoen word. Die gedragsproewe het getoon dat vir sekere pestisiede E. fetida 'n sensitiewe bioindikator van akute en/of sub-akute letale toksisiteits toetse kan wees, maar nie noodwendig vir ander pestisiede nie. Die doel van laboratoriumstudies is om so veel as moontlik inligting te versamelom vertroubare ekstrapolasie te kan maak na situasies in die veld vanaf laboratorium data. Laboratorium-na-veld ekstrapolasies is dikwels baie gekompliseerd as gevolg van die fisies-chemiese samestelling van die grond, die onvoorspelbare manier waarop chemiese pestisiede met die grond reageer en die reaksie van die grondorganismes op chemiese biosiede in die grond. Verdere studies moet gedoen word om so deeglik maanlik die mate van die impak wat die verskillende bestuurspraktyke op die grond fauna het, te verstaan op Plaisir de Merle.

Although a considerable amount of work has been done on the fauna of the soil of temperate forests and pastures, very little is known about that of tropical and sub-tropical soils. Most of the work on tropical soils concerns the fauna of tropical forests ... . The present investigation represents an attempt to discover the effect of an imported perennial tropical and sub-tropical plant, the Pineapple, on the soil fauna of a semi-arid region (rainfall 15-25 inches). Intro., p. 1-2

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