The pulp and paper industry in New Zealand annually produces over one hundred thousand dry tonnes of solid waste due to the treatment of pulp and paper mill effluents, the majority of which is currently landfilled. The New Zealand Waste Management Strategy (2002) has set a target for the diversion of commercial organic wastes from landfill to beneficial use to exceed 95% by 2010 . Effluents produced by softwood pulp mills, such as in New Zealand, contain high concentrations of naturally derived resin extractive compounds that are toxic to fish and other aquatic organisms. Improvements in waste water treatment technology has enabled the industry to meet rigorous discharge standards, however, this has resulted in an increase in the production of pulp mill effluent solids which require disposal. This has become an issue for the pulp and paper industry, especially as current landfill space is limited. Land application has been used for many years as a means of disposal of pulp mill wastes. While most studies investigating land application of pulp mill effluent solids have concluded that the risk posed to the environment is low, few have investigated the potential toxicity of these wastes to soil organisms, and these studies did not directly address the effects of resin extractive compounds. Resin extractives have been shown to be recalcitrant and to accumulate in anaerobic sediments. It is not known to what extent resin extractives are bioavailable or degradable in land applied Pulp mill effluent solids (PMES), or their potential to bioaccumulate in soil organisms. This PhD thesis research sought to extend the knowledge on the environmental fate and effects of pulp mill effluent wastes. It focused on terrestrial systems, which have not been well studied in this respect. Four chemically distinct softwood pulp mill effluent solids, a primary treatment solid and three secondary treatment biosolids, were used to investigate their effects on soil organisms and soil functions. An interdisciplinary approach was adopted, which incorporated three main areas of study, as follows: 1. A comprehensive resin extractives analysis of the pulp mill effluent solids undertaken so that effects on soil organisms and soil functions could be related to the resin extractives chemistry of the individual pulp mill effluent solids tested. 2. A battery of bioassays used to investigate the toxicity of the selected pulp mill effluent solids. 3. A field trial set-up to investigate how pulp mill effluent solids affected soil functions and also to investigate the decomposition of pulp mill effluent solids and of resin extractives in these solids. Three hypotheses tested were: I. Pulp mill effluent solids are toxic to soil organisms. II. Resin extractives in pulp mill effluent solids are recalcitrant in the terrestrial environment. III. Pulp mill effluent solids will cause significant measurable negative impacts on soil functional capacity. A wide range of resin extractives compounds were identified in pulp mill effluent solids, and concentrations of individual compounds varied widely between the different pulp mill effluent solids tested. During the two years after field application of the pulp mill effluent solids, resin extractives declined, however, decay rates of individual compounds were variable. The decay rate of compounds was influenced by the type of pulp mill effluent solids containing these compounds and not by the initial concentration of compounds. All compounds, including resin acids, degraded rapidly in the applied primary solid and in one of the applied biosolids, with average half-lives calculated ranging from three to twelve months. In the other biosolids, resin acids were recalcitrant with average half-lives calculated to be nearly ten years. Laboratory bioassays conducted on oats, earthworms and enchytraeid worms indicated that pulp mill effluent solids had low toxicity to these organisms. An aquatic bioassay organism, however, was acutely affected by aqueous extracts from pulp mill effluent solids. Earthworms were shown to bioaccumulate some resin extractive compounds to a limited extent, indicating that resin extractives were bioavailable in pulp mill effluent solids. Enchytraeid reproduction was reduced by exposure to some pulp mill effluent solids but this was not correlated to resin extractives concentration of the solids tested. Field applied pulp mill effluent solids significantly enhanced the fluxes of CO2 from the soil surface. When mass losses of pulp mill effluent solids carbon were taken into account, it was shown that these solids had little effect on soil respiration. Needle litterbags were placed above and below pulp mill effluent solids and in the litter horizon of a control treatment for 12 months. Needle litter decomposition was not significantly different between treatments, however, changes in enzyme activities were detected in litter beneath pulp mill effluent solids compared to control needle litter that had not been exposed to pulp mill effluent solids. The decomposition rate of field applied pulp mill effluent solids was slow, with half-lives extrapolated to be between five and twenty five years. The decomposition rate appeared to be influenced by the pools of carbon available for decomposition, with primary solids decaying significantly faster than biosolids due to a higher cellulose component. The conclusions of the PhD thesis research are, therefore, that generally, pulp mill effluent solids used in the study were demonstrated to be relatively benign and appear to pose a low risk to the terrestrial ecosystem when applied to soil. However, a cautious approach is still recommended to land application, based on the extensive evidence of disruption to aquatic ecosystems, and because pulp mill effluent solids will take many years to decompose and resin acids are recalcitrant in some pulp mill effluent solids. Further research is recommended to elucidate mechanisms of action by resin extractives in soil organisms and the ultimate fate of these compounds in the soil compartment.

Thesis (MScAgric)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Localized calcium (Ca) deficiencies frequently develop independent from total Ca supply and total fruit Ca concentration. Bulk mineral analyses is therefore not completely suitable for determination of the susceptibility of fruit in developing Ca-linked fruit physiological disorders like bitter pit, as it supplies insufficient information regarding the spatial accumulation of Ca within the fruit. Additional Ca is applied either as soil or foliar applications, where soil applications are applied either after fruit set (pre-harvest) or in the period after harvest. The contribution of these different methods of Ca application to the total Ca concentration in "Braeburn" fruit was quantified over three consecutive growing seasons. Foliar applications have been proven to be successful in suppressing bitter pit development and improving the Ca status of the fruit. The effectiveness of different formulations of foliar Ca products in influencing these parameters was also determined. Furthermore, the distribution pattern of fruit Ca resulting from different application strategies was mapped using particle induced X-ray emission technology. In the "Braeburn" trial, mineral analyses indicated no significant differences between treatments in terms of Ca concentration at 80 days after full bloom (dafb). However, when soil applications occurred with active root growth (visually monitored), treatments differed significantly 80 dafb. Weekly foliar Ca applications from 28 dafb resulted in higher fruit Ca concentrations 80 dafb than a pre-harvest soil Ca application (January, 2010). A possible explanation for the inefficiency of pre-harvest soil Ca is the disintegration of xylem vessels from 40 dafb (before root uptake) for sensitive cultivars such as Braeburn. Bitter pit initiation has been shown to occur in the earlier part of the season. This, together with a reduced Ca supply to the fruit early in the season due to xylem disintegration (for sensitive cultivars), indicates the importance of early season foliar Ca applications. PIXE analyses were used to establish the radial Ca distribution in apples. Ca was concentrated in the skin and core, with very low values in the outer cortex. PIXE results indicated fruit Ca concentrations to be the lowest in the pre-harvest soil application treatment. This was in agreement with mineral analyses results. Ca enriched areas resulting from effective Ca delivery via the vascular bundles, had a profound effect on fruit Ca concentrations in the immediate core and cortex. At harvest, this effect was much more subtle and emphasizes the importance of untimely xylem rupturing on eventual fruit Ca concentration. At 80 dafb, treatments where foliar Ca was applied showed higher Ca concentrations in the outer cortex (where symptoms of bitter pit typically occur). Calflo™ fruit had significantly higher Ca concentrations in "Braeburn" compared to fruits from Foliar GS™ and GG™ treatments. Calflo™ and Calcimax™ had a higher active Ca percentage (12%) compared to Foliar GSTM and GGTM (10%). Adding the Lecithin™ (surfactant) to Calcimax™ is not recommended as it did not improve its uptake. In "Golden Delicious", the commercial spray program of seven, weekly foliar applications (Calcinit™) resulted in fruit with significantly higher Ca concentrations compared to other treatments. / AFRIKAANSE OPSOMMING: Kalsium (Ca) tekorte ontstaan gewoonlik in gelokaliseerde areas in die appelvrug en ontwikkel dikwels ten spyte van voldoende totale vrug Ca. Minerale analises van heel vrugte verskaf dus nie genoeg inligting aangaande die verspreiding van Ca in die vrug wanneer die ontwikkelling van fisiologiese defekte soos bitterpit ter sprake is nie. Addisionele Ca word gewoonlik aangewend as blaar- of grondtoedienings, waar grondtoedienings tipies voor-oes (net na set) of in die na-oes periode, toegedien word. Die bydraes van die verskillende toedieningsmetodes tot die totale Ca konsentrasie van "Braeburn" appels is geëvalueer oor drie agtereenvolgende seisoene. Blaartoedienings van Ca word algemeen gebruik om die voorkoms van bitterpit te beheer en die Ca konsentrasie van die vrug te verhoog. Die effektiwiteit van `n reeks blaartoedienings-produkte om hierdie faktore te verbeter, is ook ondersoek. Die spesifieke verspreiding van die Ca in die vrug is gekarteer na gelang van elke toediening deur middel van PIXE-analises (Particle induced X-ray emission). In die "Braeburn" proef was daar geen beduidende verskille in terme van vrug Ca konsentrasie op 80 dnvb (dae na volblom) nie. Daarteenoor, was daar wel beduidende verskille by 80 dnvb toe grond toedienings saam met aktiewe wortelgroei geskied het (visuele inspeksie). Weeklikse blaartoedienings vanaf 21 dnvb het gelei tot vrugte met betekenisvol hoër Ca konsentrasies as die behandeling waar grondtoedienings slegs voor-oes geskied het (Januarie 2010). `n Moontlike oorsaak vir die oneffektiwiteit van voor-oes grondtoedings is die vroeë disintigrasie van xileem vesels in die vrug (soms voor 40 dnvb en voor die aanvang van wortelopname) in sensitiewe kultivars soos "Braeburn". Hierdie vroeë inhibering van Ca voorsiening, tesame met die vroeë inisiasie van bitterpit, beklemtoon die belangrikheid van blaarbespuitings vroeg in die seisoen. Die PIXE-analises wat aangewend is om die radiale verspreiding van Ca in die vrug te bepaal het getoon dat Ca meestal in die skil en kern van die vrug gekonsentreer was, met baie lae konsentrasies in die buitenste korteks. Die laagste Ca konsentrasies is waargeneem in vrugte van die behandeling waar voor-oes Ca slegs as `n grondtoediening geskied het. Hierdie waarneming is in ooreenstemming met die mineraalanalise resultate. Ca verykte areas, afkomstig van die naby geleë vaatbundels (xileem vesels), het egter die grootste effek op vrug Ca konsentrasie gehad. Hierdie effek was nie so groot by oes nie en beklemtoon dus die belangrikheid van die funksionaliteit van die vaatbundels. Blaartoedienings kon die Ca konsentrasie in die buitenste korteks suksesvol verhoog - waar simptome van bitterpit tipies voorkom. Die Calflo™ behandeling het beduidende hoër Ca konsentrasies gehad as die Foliar GS™ en GG™ behandelings. Die Calflo™ en Calcimax™ behandelings het `n hoër aktiewe Ca persentasie (12%) relatief tot die Foliar GS™ en GG™ (10%) behandelings bevat. Die byvoeging van Lecithin™ by Calcimax™ word nie aanbeveel nie, omdat dit geensins Ca opname vermeerder het nie. In die "Golden Delicious" proef het die kommersiële behandeling (Sewe weeklikse spuite van Calcinit™) gelei tot vrugte met die hoogste Ca konsentrasie van al die behandelings.

Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-05-02T21:36:02Z No. of bitstreams: 2 Dissertação - Marluce Silva Sousa - 2007.pdf: 8936843 bytes, checksum: 58d5acab11b603d08a87f96d020429c6 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-05-05T12:41:07Z (GMT) No. of bitstreams: 2 Dissertação - Marluce Silva Sousa - 2007.pdf: 8936843 bytes, checksum: 58d5acab11b603d08a87f96d020429c6 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-05-05T12:41:08Z (GMT). No. of bitstreams: 2 Dissertação - Marluce Silva Sousa - 2007.pdf: 8936843 bytes, checksum: 58d5acab11b603d08a87f96d020429c6 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2007-03-30 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The “Ribeirão Sujo” is a right edge tributary stream of “Rio Verde”, that is, for its time, a tributary of “Paranaíba” river. Its watershed encloses a 40 sq miles (165 km2) area inside Serranópolis municipality, into the Goiás southwest micro region, that features extensive spots of degraded sandy soils, called “sandy spots”. The natural circumstances and landscape transformations by the social processes was analyzed in order to understand this sandy spots development. The analysis was based also on individual and integrated evaluation of the landscape physical elements, from which six landscape units had been selected. The landscape units, potentialities and limitations, were evaluated, based on: soil agricultural capacity, potential fragilities and environment laws. Landscape changes by socioeconomic process and its historical changes were verified by comparing soil use into different cycles, as well as its implications into the landscape units. The Ribeirão Sujo watershed landscape crosses a series of transformations resulting from the social activities that were established on it. The most important of these transformations takes place from the 80's, with the beginning of modern agricultural activities, mainly the sugar cane. Finally, it was analyzed the sandy spots distribution and characteristics, identifying its aspects of origin and evolution, emphasizing the understanding of soil degradation level. The sandy spots growth process wraps up a dynamic that unchained from the improper soil management in a high potential fragility area, originating small sand spots, whose descriptive evolution comprises, generally, the following steps: firstly, the remove of native vegetation and the introduction of sugar cane culture on the area. After, a grass type, naming brachiaria sp, was sowed, whose establishment became precarious in consequence of the low soil fertility and inadequate management, unchaining erosive processes and reduction in nutrients and organic substances. Finally, the relative excess of pasture-pressure determined the total collapse of the pasture and of the weak structure of the topsoil. These facilitate the sandy spots expansion. The sandy spots extension already covers 1.4 % of the watershed area, where the greatest spot reaches approximately 79 ha. This sandy spots occupies various topographic positions, with bigger incidence in convex slopes and, secondarily, in concave slopes and tops. At present, it's verify in the sandy spots the occurrence of sheet erosion and, with lesser extend, rill and aeolian erosion; however, it was not verify exclusive causal analogy between erosion and sandy spots growth, nor the sandy spots occurrence were determined only by the sand deposition. Concluding, one of the main factors that determine the sandy spots growth is the soil use and management. It's suggested, immediately, the implementation of mitigating measures in order to restrain the sandy spots advancement and, in the future, its possible recovering. / O Ribeirão Sujo é afluente da margem direita do Rio Verde que, por sua vez, é afluente do Rio Paranaíba. Sua microbacia abrange área de 165 km2 no município de Serranópolis, na microrregião Sudoeste de Goiás, apresentando extensas manchas de solos arenosos degradados e sem cobertura vegetal, chamados de “areais”. Nesta microbacia foram analisados os condicionantes naturais e as transformações da paisagem pelos processos sociais para compreender a formação dos areais. A análise baseou-se na avaliação individual e, também, integrada dos elementos físicos da paisagem, a partir dos quais foram estabelecidas seis unidades de paisagem. Avaliaram-se as potencialidades e limitações das unidades de paisagem com base na aptidão agrícola das terras, na fragilidade potencial e na legislação ambiental. Verificou-se a transformação da paisagem por processos sócio-econômicos, identificando-se suas transformações históricas e comparando-se o uso da terra em diferentes períodos, bem como suas implicações nas unidades de paisagem. A paisagem da bacia do Ribeirão Sujo sofreu uma série de transformações impostas pelas atividades sociais que nela se implantaram. As mais significativas ocorreram a partir da década de 1980, com a introdução de atividades agrícolas modernizadas, principalmente da monocultura da cana-de-açúcar. Por fim, analisou-se a distribuição e características dos areais, identificando-se aspectos de sua origem e evolução, com ênfase na compreensão do nível de degradação do solo. O processo de formação de areais envolve uma dinâmica que se desencadeou a partir do manejo inadequado do solo numa área de forte fragilidade potencial, originando pequenas manchas de areia exposta, cujo histórico evolutivo compreende, em geral, as seguintes etapas: retirada da vegetação nativa de cerrado, cultivo da cana-de-açúcar, num primeiro momento, e após, semeadura de braquiária, cujo estabelecimento tornou-se precário em função da fertilidade e do manejo do solo, desencadeando processos erosivos e redução nos teores de nutrientes e de matéria orgânica. Por fim, a excessiva pressão de pastejo determinou o colapso total da fraca estrutura da camada superficial do solo e da própria pastagem, o que, por sua vez, facilitou a expansão dos areais. A dimensão dos areais já perfaz 1,4% da área da microbacia, sendo que o maior atinge cerca de 79 ha. Esses areais ocupam diversas posições topográficas, com maior incidência em rampas convexas, secundariamente, rampas côncavas e topos. Atualmente, verifica-se nos areais a ocorrência de erosão laminar e, secundariamente, de erosão linear e eólica; entretanto, não se verifica relação causal exclusiva entre erosão e formação de areais, nem a ocorrência do areal é determinada unicamente pela deposição de areia. Concluiu-se que um dos principais fatores desencadeadores da formação de areais é o uso/manejo do solo. Sugere-se, de imediato, a implantação de medidas mitigadoras para conter o avanço dos areais e, com tempo, a sua possível recuperação.