Salinisation of the shallow groundwater system has occurred coincident with the development of irrigation in the Coleambally Irrigation Area. Salinisation in irrigation areas has previously been attributed to the evaporative concentration of the water table; however, there are other sources of salt such as the accumulation of rainfall by vegetation and the dry deposition of salt-laden dusts. A significant store of crystalline gypsum, together with high concentrations of Na, Mg and Confidence limit, was found within the previously unsaturated zone of the Upper Shepparton Formation. The salt store was identified both within and outside of the groundwater mound; therefore evaporative concentration of the water table cannot be the source of salt. The transition from regional groundwater quality, as applied as irrigation to the ground surface, to shallow groundwater quality is simply explained by solubilisation of this salt store in the presence of soil CO2. Dating of basal palaeochannel sands indicates that the identified salt store, a profile of only 20 m, was accumulated during the last glacial cycle. Radiocarbon dating indicates that the peak in eluate salinity, at approximately 2 m below ground surface, is between 15,000 and 25,000 years old, coincident with the Last Glacial Maximum. The Last Glacial Maximum was a period of significantly enhanced aridity on the Australian continent. It was also found that the peak in eluate salinity coincided with a bi-modal particle size distribution. The bi-modal signature implies that these sediments were subject to the aeolian accession of dusts. It was found that the contribution of salt from dry deposition of dusts exceeded the contribution from rainfall by at least 1.9 to 11 times during the last glacial cycle. The results of this study imply that salt-laden dusts have, and continue to play an important role in the salinity and sodicity of soils in the Coleambally Irrigation Area and beyond.

Diskette for IBM/PC in pocket on back end paper. Copies of author's previously published articles inserted. Bibliography: leaves 186-207. An evaluation of spatial and temporal variation in composition of soil solutions collected from a hydro-toposequence with seasonally saturated soils ranging from Xeralfs to Aqualfs. The sub-catchment is under native eucalyptus and is formed from granite gneiss. The study shows that mineral weathering under eucalypt vegetation contributes substantially to the quantity of elements measured in soil solution with some aeolian salts. Migration of soil solutions to low lying areas promotes dryland salinity in these landscapes.

D. Tech. Engineering: Civil. / Aims to map and model the salinity trends in Vaal Harts irrigation schemes in Jan Kempdorp, Northern Cape Province of South Africa using Landsat SRS, GIS computational tools (IDRIS and ERDAS). The resulted maps and models will aid the effective management of salinity problem and thereby minimizing its occurrence in the future through planning and policy formulation, on the irrigation scheme within the context of environmental sustainability.

Salinisation of the shallow groundwater system has occurred coincident with the development of irrigation in the Coleambally Irrigation Area. Salinisation in irrigation areas has previously been attributed to the evaporative concentration of the water table; however, there are other sources of salt such as the accumulation of rainfall by vegetation and the dry deposition of salt-laden dusts. A significant store of crystalline gypsum, together with high concentrations of Na, Mg and Confidence limit, was found within the previously unsaturated zone of the Upper Shepparton Formation. The salt store was identified both within and outside of the groundwater mound; therefore evaporative concentration of the water table cannot be the source of salt. The transition from regional groundwater quality, as applied as irrigation to the ground surface, to shallow groundwater quality is simply explained by solubilisation of this salt store in the presence of soil CO2. Dating of basal palaeochannel sands indicates that the identified salt store, a profile of only 20 m, was accumulated during the last glacial cycle. Radiocarbon dating indicates that the peak in eluate salinity, at approximately 2 m below ground surface, is between 15,000 and 25,000 years old, coincident with the Last Glacial Maximum. The Last Glacial Maximum was a period of significantly enhanced aridity on the Australian continent. It was also found that the peak in eluate salinity coincided with a bi-modal particle size distribution. The bi-modal signature implies that these sediments were subject to the aeolian accession of dusts. It was found that the contribution of salt from dry deposition of dusts exceeded the contribution from rainfall by at least 1.9 to 11 times during the last glacial cycle. The results of this study imply that salt-laden dusts have, and continue to play an important role in the salinity and sodicity of soils in the Coleambally Irrigation Area and beyond.

Diskette for IBM/PC in pocket on back end paper. / Copies of author's previously published articles inserted. / Bibliography: leaves 186-207. / xvii, 246 leaves : ill., maps ; 30 cm. + 1 computer disk (3 1/2 in.) / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / An evaluation of spatial and temporal variation in composition of soil solutions collected from a hydro-toposequence with seasonally saturated soils ranging from Xeralfs to Aqualfs. The sub-catchment is under native eucalyptus and is formed from granite gneiss. The study shows that mineral weathering under eucalypt vegetation contributes substantially to the quantity of elements measured in soil solution with some aeolian salts. Migration of soil solutions to low lying areas promotes dryland salinity in these landscapes. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science, 1996?

Submitted by Mario BC (mario@bc.ufrpe.br) on 2016-07-05T13:55:57Z No. of bitstreams: 1 Rafaela Pereira Souza de Araujo.pdf: 684938 bytes, checksum: 1821eb46b80b10737e0fd55c576a0aae (MD5) / Made available in DSpace on 2016-07-05T13:55:57Z (GMT). No. of bitstreams: 1 Rafaela Pereira Souza de Araujo.pdf: 684938 bytes, checksum: 1821eb46b80b10737e0fd55c576a0aae (MD5) Previous issue date: 2016-02-23 / One of the consequences of environmental degradation is soil salinization. In this context, it is estimated that in Brazil, of the 4.5 million hectares that are compromised by salinization, most located in the northeastern semi-arid region. A strategy to recover these degraded areas would be the insertion and proper handling of plant species such as Jatropha. Keeping in view the potential Jatropha, this study aimed to evaluate the physiological responses of seeds and Jatropha curcas L. seedlings subjected to salt stress. Two tests were performed at the Federal Rural University of Pernambuco, using seeds provided by Embrapa Agroenergy. In the test I the seeds were put in germistest paper and moistened with solutions 0, 50, 75 and 100 mM NaCl and placed in germinator. We evaluated the germination percentage, germination speed index, average germination time, shoot length, root and totality, fresh and dry weight of shoot, root and analysis of organic solutes. Already for the test II after germination in washed sand, plantlets were transferred to vessels containing 12 kg of washed sand. During the acclimation period they were watered with nutrient solution ½ strength Hoagland and Arnon and water. The experimental design was composed by the imposition of the same salt solutions than those used in the test I and two evaluation periods (15 and 30 days after differentiation of treatments). We analyzed the growth, gas exchange, water relations, the content of photosynthetic pigments and organic solutes. A reduction in the emergency speed index, initial growth and carbohydrates and proline of the jatropha root. The average time of germination is increased and also the organic solutes present in the shoot at the level of 75 mM NaCl. Salinity affects the germination performance of Jatropha seeds. In general, the variables related to growth, decreased from the level of 50 mM NaCl after 15 and 30 days of salt stress. Regarding gas exchange, Stomatal closure was was observed for the same level of salinity, being more pronounced in seedlings subjected to treatments of 75 and 100 mM NaCl, from 15 days of salt stress. For water relations, there are reductions in the TRA with increasing salinity in the two times of evaluation (4 and 12h). Similarly, after 30 days of salt stress, it was found reductions in photosynthetic pigments and chlorophyll content in all evaluated saline treatments. Regarding organic solutes, the levels of carbohydrates and amino acids in the leaves and roots were affected by salinity mainly in the levels of 75 and 100 mM NaCl, since proline was not indicative of stress for the species under study. Jatropha plants when subjected to salinity up to 100 mM NaCl has committed its initial development, but the species does not paralyze their growth. / Uma das consequências resultantes do processo de degradação ambiental é a salinização do solo. Nesse contexto, estima-se que no Brasil, dos 4,5 milhões de hectares que estejam comprometidos pela salinização, a maioria localiza-se na região do semiárido nordestino. Uma estratégia para recuperação dessas áreas degradadas seria a inserção e manejo adequado de espécies vegetais, tais como o pinhão manso. Tendo em vista as potencialidades do pinhão manso, a presente pesquisa objetivou avaliar as respostas fisiológicas em sementes e mudas de Jatropha curcas L. submetidas ao estresse salino. Dois ensaios foram realizados na Universidade Federal Rural de Pernambuco, utilizando sementes fornecidas pela Embrapa Agroenergia. No ensaio I as sementes foram postas em papel germistest e umedecida com soluções de 0, 50, 75 e 100 mM de NaCl e acondicionadas em germinador. Avaliou-se a porcentagem de germinação, índice de velocidade de germinação, tempo médio de germinação, comprimento da parte aérea, da raiz e total, matéria fresca e seca da parte aérea, raiz e análises dos solutos orgânicos. Já para o ensaio II, após a germinação em areia lavada, as plântulas foram transferidas para vasos contendo 12 Kg de areia lavada. Durante o período de aclimatação estas foram regadas com solução nutritiva a ½ força de Hoagland e Arnon e com água. O delineamento experimental foi composto pela imposição das mesmas soluções salinas que as utilizadas no ensaio I e dois períodos de avaliação (15 e 30 dias após a diferenciação dos tratamentos). Analisou-se o crescimento, as trocas gasosas, as relações hídricas, os teores de pigmentos fotossintéticos e os solutos orgânicos. Verificou-se redução no índice de velocidade de emergência, no crescimento inicial e nos carboidratos e prolina da raiz de pinhão manso. Já o tempo médio de germinação é aumentado e também os solutos orgânicos presentes na parte aérea no nível de 75 mM de NaCl. A salinidade compromete o desempenho germinativo de sementes de pinhão manso. De forma geral, as variáveis relacionadas ao crescimento, apresentaram redução a partir do nível de 50 mM de NaCl após 15 e 30 dias de estresse salino. Em relação às trocas gasosas, o fechamento estomático foi constatado para este mesmo nível de salinidade, sendo mais acentuado nas mudas submetidas aos tratamentos de 75 e 100 mM de NaCl, a partir de 15 dias de estresse salino. Para as relações hídricas, verificam-se reduções no TRA com o aumento da salinidade nos dois horários de avaliação (4 e 12h). Da mesma forma, após 30 dias de estresse salino, constatouse reduções nos pigmentos fotossintéticos e no índice de clorofila em todos os tratamentos salinos avaliados. Com relação aos solutos orgânicos, os teores de carboidratos e aminoácidos nas folhas e raízes foram afetados pela salinidade principalmente nos níveis de 75 e 100 mM de NaCl, já a prolina não foi um indicativo de estresse para a espécie em estudo. Plantas de pinhão manso quando submetidas à salinidade de até 100 mM de NaCl tem seu desenvolvimento inicial comprometido, entretanto a referida espécie não paralisa seu crescimento.

Submitted by (lucia.rodrigues@ufrpe.br) on 2016-08-17T12:15:41Z No. of bitstreams: 1 Marcio Flequisson Alves Miranda.pdf: 1217281 bytes, checksum: bd45c2f7f20927f1da595dfd05965a6a (MD5) / Made available in DSpace on 2016-08-17T12:15:42Z (GMT). No. of bitstreams: 1 Marcio Flequisson Alves Miranda.pdf: 1217281 bytes, checksum: bd45c2f7f20927f1da595dfd05965a6a (MD5) Previous issue date: 2013-02-20 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / In Northeastern Brazil, in recent decades, with the increase of irrigation using in irrigated perimeters, often with inadequate management to local conditions, the soil salinization and sodification processes have intensified, promoting degradation and abandonment of large areas previously productive. Thus, we carried out a field survey to investigate the soil degradation in irrigated perimeter situated in the municipality of Custodia, semiarid region in Pernambuco, Brazil. Firstly were identified areas with degraded soils by salts excess, and also was done the experiment assembly with the intent to recover those areas through the application of organic and chemicals compounds, besides the technique of phytoremediation with Atriplex nummularia. For that, soil samples were taken in all 55 plots that make up the perimeter in the 0-10, 10-30 and 30-60 cm layers for the soils physical and chemical characterization, and chemical analyzes of the water used on the perimeter during periods of July/2009, January/2010, July/2010 and January/2011. After the selection of the degraded area into the irrigated perimeter, was mounted an experiment to recover the degraded soil by the evaluation of the treatments: 1) planting of Atriplex nummularia Lindl, 2) application of bovine manure, 3) sheep manure, 4) polymer, 5) gypsum and 6) control (witness). Four samples were taken, the first being at the same time of the experiment assembly (October 2009). After that, three more samples were taken, at six (April 2010), twelve (October 2010) and eighteen months (April 2011) after experiment assembly. Soil samples were collected at 0-10, 10-30 and 30-60 cm depth for the chemical analyzes. To evaluate the physical properties, soil samples were collected in the first (October 2009) and in the last (April 2011) collection at 0-10 and 10-30 cm layers. Were monitored the soil attributes in relation to treatment application with respect to time. The soils of the irrigated perimeter from Custódia are in the process of degradation and need to have their properties monitored over time to prevent its development. Among the cations evaluated, soluble and exchangeable Na+ was what was in higher concentrations, followed by the Cl- and by the RAS variable, besides increasing the PST in depth. The phytoremediation technique was effective in improving the soils quality and the application of sheep manure and polyacrylamide based polymer also acted positively in improving the quality of soil chemistry and physics. / Na Região Nordeste do Brasil, nas últimas décadas, com o incremento da irrigação em perímetros irrigados, muitas vezes com manejo inadequado às condições locais, os processos de salinização e sodificação de solos têm se intensificado, promovendo a degradação e abandono de extensas áreas anteriormente produtivas. Assim, realizou-se o levantamento da situação de degradação do Perímetro Irrigado de Custódia, no Sertão de Pernambuco, onde foram identificadas áreas com problemas de excesso de sais, seguindo-se de montagem de experimento para recuperação de uma dessas áreas, através da aplicação de compostos orgânicos e químicos, além da técnica da fitorremediação com Atriplex nummularia. Para isso, foram realizadas amostragens de solos em todos os 55 lotes que compõem o perímetro nas profundidades de 0-10, 10-30 e 30-60 cm para a caracterização física e química dos solos, além das análises químicas das águas utilizadas no perímetro nos períodos de Julho/2009, Janeiro/2010, Julho/2010 e Janeiro/2011. Após seleção de área degradada do perímetro, foi montado experimento de recuperação do solo testando-se os tratamentos: 1) plantio de Atriplex nummularia Lindl, 2) aplicação de esterco bovino, 3) esterco ovino, 4) polímero, 5) gesso e 6) controle (testemunha). Foram realizadas quatro amostragens, sendo a primeira no momento da montagem do experimento (Outubro de 2009), aos seis (Abril de 2010), aos doze (Outubro de 2010) e aos dezoito meses (Abril de 2011). As amostras de solo foram coletadas nas camadas de 0-10, 10-30 e 30-60 cm de profundidade para realização das análises químicas. Para a realização das análises físicas do solo coletaram-se amostras de solo na primeira coleta (Outubro de 2009) e na ultima (Abril de 2011) nas profundidades de 0-10 cm e 10-30 cm. Foram monitorados os atributos do solo com a aplicação dos tratamentos em função do tempo. Os solos do Perímetro Irrigado de Custódia encontram-se em processo de degradação e precisam ter suas propriedades monitoradas ao longo do tempo para evitar sua evolução. Entre os cátions avaliados, o Na+ solúvel e trocável foi o que esteve em concentrações mais elevadas, seguido pelo Cl- e pela variável RAS, além do aumento da PST em profundidade. A técnica da fitorremediação foi efetiva na melhoria da qualidade dos solos estudados e a aplicação do esterco ovino e do polímero a base de poliacrilamida também atuaram positivamente na melhoria da qualidade química e física do solo.

The work presented in this thesis stemmed out of the apparent lack of a method for incorporating salinity effects into environmental life cycle assessments. Salination of the water resources is a well-known problem in South Africa, and is of strategic concern. Any environmental decision support. tool that does not allow the evaluation of salinity effects therefore has limited applicability in the South African context. The starting-point for the work presented in this thesis was to evaluate existing impact categories, and the characterisation models used to calculate equivalency factors for these impact categories, in an attempt to incorporate salinity effects into existing categories and/or characterisation models. The types of effects that elevated (above normal background levels) dissolved salt concentrations have on the natural and man-made environment were evaluated, and it was concluded that, although there was some overlap with existing impact categories, some of the salinity effects could not be described by existing impact categories. It was also concluded that there are clear and quantifiable causal relationships between releases to the environment and salinity effects. A separate salinity impact category was therefore recommended that includes all salinity effects, including; aquatic ecotoxicity effects, damage to man-made environment, loss of agricultural production (livestock and crops), aesthetic effects and effects to terrestrial fauna and flora. Damage to the man-made environment is evaluated in terms of effects on equipment and structures, interference with processes, product quality and complexity of waste treatment, and is used as an indicator for the environmental consequences derived from the caused additional activity in the man-made environment. Once a conceptual model for a separate salinity impact category had been formulated, existing characterisation models were evaluated to determine their applicability for modelling salinity effects. Salination is a global problem, but generally restricted to local or regional areas, and in order to characterise salinity effects, an environmental fate model would be required in order to estimate salt concentrations in the various compartments, particularly surface and subsurface water. A well-known environmental fate and effect model was evaluated to determine if it could be used either as is, or in modified form to calculate salinity potentiaIs for LCA. It was however concluded that the model is not suitable for the calculation of salinity potentials, and it was therefore decided to develop an environmental fate model that would overcome the limitations of existing model, in terms of modelling the movement of salts in the environment. In terms of spatial differentiation, the same approach that was adopted in the existing model was adopted in developing an environmental fate model for South African conditions. This was done by defining a aunit South African catchmenta (including the air volume above the catchment), which consists of an urban surface; rural agricultural soil (and associated soil moisture); rural natural soil (and associated moisture), groundwater (natural and agricultural) and one river with a flow equal to the sum of the flows of all rivers in South Africa, and a concentration equal to the average concentration of each river in the country. A non steady-state environmental fate model (or, hydrosalinity model) was developed that can predict environmental concentrations at a daily time-step in all the compartments relevant to the calculation of salinity potentials. The environmental fate model includes all the major processes governing the distribution of common ions (sodium, calcium, magnesium, sulphate, chloride and bicarbonate) in the various compartments, and described as total dissolved salts. The effect factors used in the characterisation model were based on the target water quality ranges given by the South African Water Quality Guidelines in order to calculate salinity potentials. The total salinity potential is made up of a number of salinity effects potentials, including; damage to man-made environment, aquatic ecotoxicity effects, damage to man-made environment, loss of agricultural production (livestock and crops), aesthetic effects and effects to terrestrial fauna and flora. The total salinity potentials for emissions into the various initial release compartments are shown in the table below. Initial release compartment Atmosphere River Rural natural surface Rural agricultural surface Total salinity potential (kg TDS equJkg) 0.013 0.16 0.03 1.00 The salinity potentiaIs are only relevant to South African conditions, and their use in LeA in other countries may not be applicable. This, in effect, means that the life cycle activities that generate salts should be within the borders of South Africa. It has been recognised that the LCA methodology requires greater spatial differentiation. Salination is a global problem, but generally restricted to local or regional areas on the globe, and it is foreseen that local or regional salinity potentials would need to be calculated for different areas of the earth where salinity is a problem. The LCA practitioner would then need to know something about the spatial distribution of LCA activities in order to apply the relevant salinity potentials. The LCA practitioner should also take care when applying the salinity potentials to prevent double accounting for certain impacts. Currently, this is simple because no equivalency factors exist for common ions, or for total dissolved salts as a lumped parameter. The distribution of salinity potentials, which make up the total salinity potential, appears to be supported by the environmental policies and legislation of South Africa, in which irrigation using saline water is listed as a controlled activity, and subject to certain conditions. The major recommendations regarding further work are focussed on the collection of data that will allow further refinement of the model, and to decrease the uncertainty and variability associated with the results. The values of the published equivalency factors are dependent on the mathematical definition of the local or regional environment, and these values have been calculated for Westem European conditions. Equivalency factors may vary by several orders of magnitude, depending on how the local or regional conditions have been defined. It is therefore recommended that the model developed in this work ultimately be included into a global nested model that can be used to calculate equivalency factors for other compounds, including heavy metals and organic compounds. This would result in equivalency factors for all compounds that are relevant to South Africa. / Thesis (Ph.D.)-University of Natal, Durban, 2003.

A field-based project was undertaken to develop and test a mechanism which would allow for the correlation of the health of vegetation surrounding playa lakes in south-west Australia with the natural variation in salinity and waterlogging that occurs spatially and temporally in natural systems. The study was designed to determine threshold ranges of vegetation communities using moderately extensive data over short temporal periods which will guide the design of potential engineering solutions that manipulate hydrological regimes to ultimately conserve and protect native vegetation. A pair of playa lake ecosystems, surrounded by primary production land, was modelled with hydro-geological data collected from March 2006 to March 2007. The data was used to determine the hydroperiods of vegetation communities fringing playa lakes and provide insight into the areas and species that are most affected by extreme rainfall events which are hypothesised to have a significant, rapid deleterious effect on the ecosystems. The methodology was multi-faceted and included; a detailed topographical survey; vegetation surveys; hydrological and hydro-geological monitoring over a 12 month period. 4 The hydro-geological data and vegetation data was linked with the topographical survey at a high resolution for spatial analysis in a Geographic Information System (GIS) to determine the degree of waterlogging experienced by vegetation communities over the monitoring period. The study has found that the spatial and temporal variability of hydroperiods has been reduced by rising groundwater levels, a result of extensive clearing of native vegetation. Consequently populations are becoming extinct locally resulting in a shift in community composition. Extreme summer rainfall events also have a significant impact on the health of vegetation communities by increasing the duration of waterlogging over an annual cycle and in some areas expanding the littoral zone. Vegetation is most degraded at lower positions in the landscape where communities are becoming less diverse and dominated by salt tolerant halophytic species as a result of altered hydrological regimes. Some species appear to be able to tolerate groundwater depths of less than 2.0 m from the surface, however there are thresholds related to the duration at which groundwater is maintained at this depth. Potential engineering solutions include groundwater pumping and diverting water through drains to maintain sustainable hydroperiods for vegetation in areas with conservation value. The effectiveness and efficiency of the engineering solutions can be maximised by quantifying thresholds for vegetation that include sustainable durations of waterlogging. The study has quantified tolerance ranges to salinity and waterlogging with data collected over 12 months but species may be experiencing a transition period where they have 5 sustained irreversible damage that will result in their eventual mortality. With long-term monitoring, the methodology developed and tested in the study can be used to quantify the long-term tolerance ranges that are important for the application of conservation approaches that include engineering solutions.

Title page, table of contents and abstract only. The complete thesis in print form is available from the University of Adelaide Library. / Transient salinity in soils is characterised by high concentrations of salts in the subsoil. Durum wheat (Triticum turgidum L. Var. durum) is less tolerant of transient salinity than locally developed bread wheat (Triticum aestivum) varieties, and this results in reliable durum production being restricted to relatively unaffected soils. Field trials were conducted to assess the relative impact of transient salinity, boron toxicity and bicarbonate on crop production and highlighted the importance of combining tolerance to all three subsoil constraints into varieties intended for widespread adoption; and if the area of durum production is to be expanded. The Na exclusion locus from the landrace Na49 was found to improve the adaptation of durum to sites affected by transient salinity and is now being intogressed into a wide range of breeding material. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1152134 / Thesis (Ph.D.) -- University of Adelaide, School of Agriculture and Wine, 2005