Conciliar as crescentes demandas da produção agrícola com a garantia da produtividade do solo exige decisões rápidas e apoiadas em informação confiável acerca de impactos esperados. Compreender o efeito de grandes dinâmicas de alteração do uso do solo sustenta decisões futuras quanto à implementação de práticas sustentáveis de manejo. O presente estudo objetivou avaliar a dinâmica da produção de sedimentos no Rio Grande do Sul em conseqüência da evolução do plantio direto a partir da modelagem em larga escala de dados secundários acesso público. Primeiramente, a validade da aplicação de um modelo de predição de erosão em larga escala foi testada no estado de São Paulo com variáveis exógenas relativas a bacias hidrográficas. À exceção da adoção de práticas de conservação, os demais fatores da Equação Universal de Perda de Solo foram calculados e espacializados em Sistemas de Informações Geográficas. Os dados de perda de solo foram combinados com parâmetros ligados a forma das bacias hidrográficas, sua declividade, a ocorrências de represamentos e matas ciliares; e usados como variáreis explicativas da carga de sedimentos nos rios através de modelos de regressão multivariada. A produção de sedimentos foi correlacionada à perda de solo estimada e à presença de grandes reservatórios nos terços inferiores das bacias (R²=0,55). Na aplicação do modelo testado, a perda de solo esteve diretamente relacionada ao uso da terra, concentrando altas taxas de erosão nas áreas ocupadas por agricultura de cultivos anuais. A partir da comprovação do método, este pôde ser utilizado na avaliação do efeito da mudança no manejo do solo em larga escala ocorrida no Rio Grande do Sul a partir da década de 80. Impulsionado por uma complexa estrutura social favorável, o Sistema Plantio Direto (SPD) foi amplamente adotado no estado. O fator cobertura do solo, que engloba uso e manejo foi obtido através dos Censos Agropecuários e monitoramentos estaduais da área de SPD dos anos de 1985, 1996 e 2006. Vinte e nove bacias hidrográficas foram determinadas a partir de estações sedimentométricas e separadas em agrícolas e de pastagem. A proporção de área agrícola determina o efeito do SPD no controle da erosão na bacia. A produção de sedimentos não variou nas áreas com pastagem e foi menor que a produção nas bacias agrícolas nos anos de 1985 e 1996. Nas áreas agrícolas, a produção de sedimentos diminuiu em 1996 e em 2006, quando se igualou à produção das bacias com pastagem. A adoção do SPD apresentou uma redução média na carga de sedimentos de 82%, valor próximo da redução das taxas de erosão testada em experimentos com plantio direto. O método sugerido permitiu a compreensão da distribuição espacial da erosão e sua dinâmica temporal em função do uso da terra. Modelos como este podem subsidiar a tomada de decisão, com potencial para avaliação de serviços ambientais fornecidos pelos agricultores, ferramentas determinantes na disseminação de práticas conservacionistas. / Reconcile the increasing demands of agricultural production with the assurance of soil productivity requires quick decisions and supported by reliable information about the expected impact. Understand the effect of large dynamic change of land use maintains future decisions regarding the implementation of sustainable agricultural management practices. This study aimed to evaluate the dynamics of sediment production in Rio Grande do Sul in consequence of the no-till evolution by large scale modeling with easily accessible data. First, the validity of applying a predictive model of erosion on a large scale was tested in the state of Sao Paulo with exogenous variables related to watersheds. Except for the adoption of conservation practices, all factors of Universal Equation of Soil Loss (USLE) were calculated and spatialized in Geographic Information Systems. The soil loss data were combined with parameters related to the shape of river basins, its slope, the occurrence of dams and riparian areas, and used as explanatory variables of the load of sediment in rivers through multivariate regression models. The sediment yield was correlated with the estimated soil loss and the presence of large reservoirs in the lower thirds of the basins (R² = 0.55). In applying the model tested, the soil loss was directly related to land use, focusing high rates of erosion in areas occupied by annual crops. From the proof of the method, this might be used in evaluating the effect of large scale changes in soil management occurred in Rio Grande do Sul from the 80s. Driven by a complex social structure, the no-till system (NT) has been widely adopted in the state. The soil cover factor, which includes the use and management, was obtained through the state Agricultural Censuses and monitoring of the area of SPD of the years 1985, 1996 and 2006. Twenty-nine watersheds were determined from sediment stations and separated into agricultural and pasture. The proportion of agricultural area determines the effect of the NT to control erosion in the basin. The sediment yield did not vary in areas with pasture and was lower than production in the agricultural basin in the years 1985 and 1996. In agricultural areas, the sediment production declined in 1996 and 2006, when it equaled the production of watersheds with pasture. The adoption of the NT showed an average reduction in sediment load of 82%, a value close to the reduction of soil erosion rates tested in experiments with tillage. The suggested method allowed the spatial understanding of the spatial distribution of erosion and its temporal dynamics as a function of land use. Models like this can support the decision-making, with potential for assessing environmental services provided by farmers, determinant tools in the spread of conservation practices.

As unidades de conservação (UC) são áreas com características naturais relevantes, com limites definidos e com o objetivo de proteção e preservação da natureza, sendo admitido apenas o uso indireto dos seus recursos naturais, o qual deve compatibilizar a conservação da natureza com o uso sustentável de parcela dos seus recursos naturais. As áreas em volta das UCs são estratégicas para a proteção da biodiversidade e para o desenvolvimento sustentável da população local. Entretanto, é necessário que hajam restrições e limites ao uso e ocupação do solo nos locais da circunvizinhança, para reduzir a influência dos impactos negativos na biodiversidade das áreas protegidas. O objetivo do presente estudo é fornecer embasamento técnico para a determinação de critérios que definam a extensão, o uso e a ocupação da zona de amortecimento (ZA) do Parque Estadual Turístico do Alto Ribeira (PETAR). Para isto foram elaborados critérios que definem: a) a extensão da zona de amortecimento e b) a utilização da zona de amortecimento. A definição da extensão da zona de amortecimento do PETAR baseou-se na delimitação das microbacias hidrográficas cujos cursos de água drenam para dentro do parque e na aproximação dos vetores antrópicos ao limite do parque. Os critérios que definiram o uso e ocupação da paisagem na zona de amortecimento foram baseados na vulnerabilidade à erosão do solo. Conclui-se que a zona de amortecimento de 10 quilômetros contempla os critérios aqui usados, abrangendo o limite das microbacias hidrográficas e os grandes fragmentos florestais. Entretanto a qualidade do parque está ameaçada pela expansão da agricultura, mineração, extração ilegal de palmito e silvicultura. A expansão dessas atividades ocorre de forma irregular em áreas de alta vulnerabilidades à erosão e coloca em risco a manutenção da qualidade do bioma protegido. / Conservation Units (UC) are areas with relevant natural features, with limits defined and with the goal of protecting and preserving nature, being admitted only the indirect use of its natural resources, which should reconcile nature conservation with the use sustainable portion of their natural resources. The areas around the UC are strategic to the protection of biodiversity and the local sustainable development of the population. However, it is necessary that there are restrictions and limits on the use and occupation of land in the surroundings, to reduce the influence of negative impacts on biodiversity in protected areas. The aim of this study is to provide a technical foundation for the determination of criteria that define the extent, use and occupancy of the buffer zone (BZ) of the Alto Ribeira Tourist State Park (PETAR). To this were developed criteria that define: a) the extent of the buffer zone and b) the use of the buffer zone. The definition of the extent of the buffer zone PETAR was based on the delineation of watersheds whose rivers drain into the park and approximation of the antropic vectors to the park boundary. The criteria that defined the use and occupancy of the landscape in the buffer zone were based on the vulnerability to soil erosion. It is concluded that the buffer zone of 10 km covers the criteria used here, covering the source of watersheds and large forest fragments. However the quality of the park is threatened by expanding agriculture, mining, illegal harvesting for palm-heart and forestry. The expansion of these activities occurs irregularly in areas of high vulnerability to erosion and can endanger the maintenance of the quality of the biome protected.

As unidades de conservação (UC) são áreas com características naturais relevantes, com limites definidos e com o objetivo de proteção e preservação da natureza, sendo admitido apenas o uso indireto dos seus recursos naturais, o qual deve compatibilizar a conservação da natureza com o uso sustentável de parcela dos seus recursos naturais. As áreas em volta das UCs são estratégicas para a proteção da biodiversidade e para o desenvolvimento sustentável da população local. Entretanto, é necessário que hajam restrições e limites ao uso e ocupação do solo nos locais da circunvizinhança, para reduzir a influência dos impactos negativos na biodiversidade das áreas protegidas. O objetivo do presente estudo é fornecer embasamento técnico para a determinação de critérios que definam a extensão, o uso e a ocupação da zona de amortecimento (ZA) do Parque Estadual Turístico do Alto Ribeira (PETAR). Para isto foram elaborados critérios que definem: a) a extensão da zona de amortecimento e b) a utilização da zona de amortecimento. A definição da extensão da zona de amortecimento do PETAR baseou-se na delimitação das microbacias hidrográficas cujos cursos de água drenam para dentro do parque e na aproximação dos vetores antrópicos ao limite do parque. Os critérios que definiram o uso e ocupação da paisagem na zona de amortecimento foram baseados na vulnerabilidade à erosão do solo. Conclui-se que a zona de amortecimento de 10 quilômetros contempla os critérios aqui usados, abrangendo o limite das microbacias hidrográficas e os grandes fragmentos florestais. Entretanto a qualidade do parque está ameaçada pela expansão da agricultura, mineração, extração ilegal de palmito e silvicultura. A expansão dessas atividades ocorre de forma irregular em áreas de alta vulnerabilidades à erosão e coloca em risco a manutenção da qualidade do bioma protegido. / Conservation Units (UC) are areas with relevant natural features, with limits defined and with the goal of protecting and preserving nature, being admitted only the indirect use of its natural resources, which should reconcile nature conservation with the use sustainable portion of their natural resources. The areas around the UC are strategic to the protection of biodiversity and the local sustainable development of the population. However, it is necessary that there are restrictions and limits on the use and occupation of land in the surroundings, to reduce the influence of negative impacts on biodiversity in protected areas. The aim of this study is to provide a technical foundation for the determination of criteria that define the extent, use and occupancy of the buffer zone (BZ) of the Alto Ribeira Tourist State Park (PETAR). To this were developed criteria that define: a) the extent of the buffer zone and b) the use of the buffer zone. The definition of the extent of the buffer zone PETAR was based on the delineation of watersheds whose rivers drain into the park and approximation of the antropic vectors to the park boundary. The criteria that defined the use and occupancy of the landscape in the buffer zone were based on the vulnerability to soil erosion. It is concluded that the buffer zone of 10 km covers the criteria used here, covering the source of watersheds and large forest fragments. However the quality of the park is threatened by expanding agriculture, mining, illegal harvesting for palm-heart and forestry. The expansion of these activities occurs irregularly in areas of high vulnerability to erosion and can endanger the maintenance of the quality of the biome protected.

Infiltration, the process of water movement through the soil surface is one of most important hydrological processes to be considered in watershed management. The process depends on rainfall, soil, vegetation and topographic conditions. The last three variables can be influenced by human land-uses. This study is concerned with the influence of landuse types (categories) on infiltration at the upper Ciliwung watershed of West-Java, Indonesia. Sixty six infiltration measurements were carried out in 5 types of land-uses i.e. natural forest, agriculture, settlement, productive (old) tea and new tea plantation areas. The measurements were done using ring infiltrometers. The data obtained were expressed in the form of Philip's equation I = st1I2 + At, where I is cumulative infiltration; S is sorptivity; t is time; A is a parameter which was calculated from saturated hydraulic conductivity (K). Crown cover, slope gradient and soil variables such as soil moisture, organic carbon content, total porosity, bulk density were also analysed from each of the 66 sites. The results of the study shows that land-use types have significant influence on these soil variables and on infiltration. Crown cover and human activities in term of land management are among the most important factors which affect soil condition. These variables mostly influence total porosity of soil which is the most important variable to determine sorptivity and hydraulic conductivity. High percentage of crown cover and less human activity in forest area result in high accumulation of litter and humus and high total porosity of soil. On the other hand, settlement and new tea plantation areas have comparatively low crown cover and more frequent human activity which result in soil compaction. Discriminant function analysis of land-use categories shows that the soil under forest is very distinct from the soils under other land-use types. However, the soils under the remaining land-use types are more similar to each other, especially between the soil of settlement and tea plantations. The rank of infiltration rate from the highest to the lowest magnitude is as follows; natural forest, agriculture, productive tea plantation, new tea plantation and settlement areas. Infiltration rates under natural forest and agriculture are significantly different from each other as well as from those in the last three land- use types. However, there are no significant differences in infiltration rates among the last three land-use types. The result of this study also provides basic information for landuse management and further research in order to solve soil and water conservation and management problems in the watershed.

<p>In the village'of Citing in the northern highlands of Tanzania, the factors: social stratification, land tenure, production strategies, investment patterns and the economic uncertainties of society are studied and their relationship to land degradation is examined. The main assumption of the study is that the causes of land degradation are so complex that a methodology that emphasises contextualisation has to be used. A methodological framework that considers inter-linkages between all these factors is developed and tested. The result of the test shows that contextualisation gives a more in-depth and complex explanation than conventional, positivist research. The study gives a detailed account of the relationship that various wealth groups have to land and land degradation in the village. It is found that all wealth groups are destructive to the land but in varying ways. The rich farmers are over-cultivating land marginal to agriculture, the middle peasants have too many cattle in the village while the poor peasants are so marginalised socially that they hardly influence land management. Those identified as having economic as well as social incentives to maintain soil fertility are the middle peasants, while the rich farmers are shown to be consciously soil-mining the former grazing areas.</p>

In the village'of Citing in the northern highlands of Tanzania, the factors: social stratification, land tenure, production strategies, investment patterns and the economic uncertainties of society are studied and their relationship to land degradation is examined. The main assumption of the study is that the causes of land degradation are so complex that a methodology that emphasises contextualisation has to be used. A methodological framework that considers inter-linkages between all these factors is developed and tested. The result of the test shows that contextualisation gives a more in-depth and complex explanation than conventional, positivist research. The study gives a detailed account of the relationship that various wealth groups have to land and land degradation in the village. It is found that all wealth groups are destructive to the land but in varying ways. The rich farmers are over-cultivating land marginal to agriculture, the middle peasants have too many cattle in the village while the poor peasants are so marginalised socially that they hardly influence land management. Those identified as having economic as well as social incentives to maintain soil fertility are the middle peasants, while the rich farmers are shown to be consciously soil-mining the former grazing areas.

The designation of World Heritage Sites (WHS) by UNESCO is the principal international and formally recognised strategy allowing the conservation of sites of outstanding cultural value throughout the world. This study demonstrates that soils and sediments influenced by cultural activities retain cultural records (soils and sediments-based cultural records, hereafter abbreviated to SSBCR) associated with WHS, and further the understanding and contribute to the cultural value of WHS. Considering The Heart of Neolithic Orkney WHS and its surrounding landscape as the study location, systematic fieldwork is combined with geoarchaeological analyses including soil organic matter content, pH, particle size distribution, phosphorus concentration, soil magnetism and thin section micromorphology to determine the nature of the SSBCR. Chronologies of the formation of SSBCR and of palaeo-environmental records were ascertained using radiocarbon analyses and optically stimulated luminescence analysis. Findings of particular importance to the interpretation of the WHS are the identification of a Late Neolithic SSBCR located between the WHS monuments. This SSBCR is a valuable cultural record of a specific Late Neolithic community and provides significant insight into the interaction between settlement and ritual aspects of the Orcadian Late Neolithic. An understanding of these interactions is of crucial importance to a fuller interpretation of the WHS and to the wider discussion of the Orcadian Neolithic. The implications of this research to other WHS designated for their cultural value are discussed, together with future conservation considerations for this specific WHS.

Driven by many factors, the water supply services (streamflow and groundwater) of many rivers in the dryland area of China have declined significantly. This aggravates the inherent severe water shortages and results in increased severity in the water use conflicts that are threatening sustainable development in the region. Innovative strategies towards more water-efficient land management are vital for enhancing water quantity to ensure water supply security. A key step in the successful development and implementation of such measures is to understand the response of hydrological processes and related services to changes in land management and climate. To this end, it was decided to investigate these processes and responses in the upper reaches of the Jing River (Jinghe), an important meso-scale watershed in the middle reaches of the Yellow River on the Loess Plateau (NW China). It has been shown that vegetation restoration efforts (planting trees and grass) are effective in controlling soil erosion on the Loess Plateau. Shifts in land cover/use lead to modifications of soil physical properties. Yet, it remains unclear if the hydraulic properties have also been improved by vegetation restoration. A better understanding of how vegetation restoration alters soil structure and related soil hydraulic properties, such as water conductivity and soil water storage capacity, is necessary. Three adjacent sites, with comparable soil texture, soil type, and topography but contrasting land cover (Black locust forest, grassland, and cropland), were investigated in a small catchment in the upstream Jinghe watershed (near Jingchuan, Gansu province). Seasonal variations of soil hydraulic properties in topsoil and subsoil were examined. Results revealed that the type of land use had a significant impact on field-saturated, near-saturated hydraulic conductivity, and soil water characteristics. Specifically, conversion from cropland to grass or forests promotes infiltration capacity as a result of increased saturated hydraulic conductivity, air capacity, and macroporosity. Moreover, conversion from cropland to forest tends to promote the formation of mesopores that increase soil water storage capacity. Tillage in cropland temporarily created well-structured topsoil, but also compacted subsoil, as indicated by low subsoil saturated hydraulic conductivity, air capacity, and plant available water capacity. An impact of land cover conversion on unsaturated hydraulic conductivities was not identified, indicating that changes in land cover do not affect functional meso- and microporosity. Changes in soil hydraulic properties and associated hydrological processes and services due to soil conservation efforts need to be considered, should soil conservation measures be implemented in water-limited regions for sustaining adequate water supply. To differentiate between the impacts of land management and climate change on streamflow, the variation of annual streamflow, precipitation, potential evapotranspiration, and climatic water balance in a small catchment of the upstream Jinghe watershed (near Pingliang, Gansu province) was examined during the period of 1955 – 2004. During this time the relative contributions of changes in land management and climate to the reduction of streamflow were estimated. A statistically significant decreasing trend of -1.14 mm y-1 in annual streamflow was detected. Furthermore, an abrupt streamflow reduction due to afforestation and construction of terraces and check-dams was identified around 1980. Remarkably, 74% of the total reduction in mean annual streamflow can be attributed to the soil conservation measures. Among various conservation measures, streamflow could be considerably reduced by afforestation and terracing (including damland creation), due to their low contribution to water yield. In contrast, slope farmland and grassland can maintain a certain level of water supply services due to higher runoff coefficients. According to a meta-analysis of the published studies on the Loess Plateau, the impact of changes in land management on annual streamflow appears to diminish with increasing catchment size while the impact of climate change appears uniform across space. This means that there is a dependency between the catchment size and the response of hydrological processes to environmental change. At least at the local scale, it appears that well-considered land management may help to ensure the water supply services. Due to limited surface water availability, groundwater is an essential water source for supporting ecosystem and socio-economic development in the dryland region. However, the groundwater process is susceptible and vulnerable to changes in climate and landscape (i.e., land cover and form) that in turn can result in profound adverse consequences on water supply services in water-limited regions. In addition, an improved understanding of the response of groundwater related processes to natural and artificial disturbances is likely to ensure more secure and more sustainable governance and management of such regions, as well as better options for adapting to climate change. Yet, this topic has seldom been researched, especially in areas that have already experienced large-scale alteration in landscape and are located in dryland regions, such as the Loess Plateau. Therefore, an investigation of the baseflow variation along the landscape change was conducted. The average annual baseflow has significantly decreased at catchment scale during the period of 1962 – 2002 without any obvious significant change in climate. At decadal scale, the reduction accounts for approximately 9% in the 1970s, 48% in the 1980s, and 92% in the 1990s, while the baseflow index declines averaging 5%, 16% and 67%, respectively. All of the monthly baseflow levels dropped at varying rates except in January, among which July was the most severe in terms of both magnitude (-4.17) and slope (-0.09 mm y-1). In perspective of landscape change, landform change (terrace and check-dam) tends to reduce baseflow by reallocation of surface fluxes and retention for crop growth causing limited deep drainage in other areas. Land cover change (i.e., afforestation) reduced the baseflow to a larger extent by enhanced evapotranspiration and thus hampered deep drainage as suggested by the soil moisture measurement underneath. The study indicates that knowledge about baseflow formation on catchment scale needs further improvement. Integrated soil conservation and water management for optimizing landscape structure and function in order to balance soil (erosion) and water (supply) related hydrological ecosystem services is vital. The governing processes to the changes of water-supply-services-related hydrological process (e.g., streamflow) are assumed to be different across space. To this end, the factors controlling streamflow were investigated on both a small and large scale. Streamflow in small catchments was found to be mainly controlled by precipitation and land cover type. On a larger scale, evaporative demand was found to be another additional major driving force. Hydrological modeling is a frequently used tool for the assessment of impacts of land use and climate change on water balance and water fluxes. However, application of the Soil and Water Assessment Tool (SWAT) model in the upstream Jinghe watershed was unsuccessful due to difficulties in calibration. The inability of the SWAT model to take the influence of terraces on steep slopes into consideration and the method how to calculate lateral flow were the main reasons for unsatisfactory calibration, at least for the current version of SWAT used in this study. Alternatively, Budyko’s frameworks were applied to predict the annual and long-term streamflow. However, the effect of changes in land management (e.g., afforestation) on streamflow could not be assessed due to a lack of vegetation factors. Therefore, an empirical analysis tool was derived based on an existing relationship for estimation. This method was found to be the most effective in reproducing the annual and long-term streamflow. The incorporation of temporal changes in land cover and form in the approach enables the estimation of the possible impact of soil conservation measures (e.g., afforestation or terracing). The importance of adaptive land management strategies for mitigating water shortage and securing the water supply services on the Loess Plateau was highlighted. A cross-sectoral view of the multiple services offered by managed ecosystems at different spatial scales under changing environments needs to be integrated to improve adaptive land management policy. In a water limited environment, such as the Loess Plateau, multiple ecosystem services including hydrological services need to be balanced with minimum trade-offs. This can only be achieved when management is based on a holistic understanding of the interdependencies among various ecosystem services and how they might change under alternative land management.

Commercial forestry is recognized for both its economic contribution as well as its environmental impact. Of particular concern, is the soil erosion and sedimentation of watercourses associated with forestry plantations. Environmental laws regulate many of the activities of the forestry sector. It is critical that the forestry sector ensure that its operations are compliant with the legal requirements that govern its use of natural resources. In pursuing legal compliance it is necessary to ensure that erosion control strategies are developed so as to ensure the positive effects of any interventions are optimised. The identification of areas that are particularly at risk to erosion or contribute to sediment delivery is an essential component in prioritising areas for management interventions. Establishing the erosion potential for commercial forestry areas is readily accomplished through the application of existing models. Process based erosion models generally have greater data requirements than the empirically derived USLE-based models. Given the paucity of data available, the latter approach was adopted. Two methods of topographic sub-factor derivation were investigated, those associated with the RUSLE (Renard, Foster, Weesies & McCool1991) and the Unit Stream Power method presented by Moore and Burch (1986). Since no existing methods identifying delivery risk areas existed, a method was developed based on principles and factors identified in the literature. Additionally, methods for identifying topographic assets, in terms of sediment attenuation, were developed. From these models three indices were derived; sediment supply, delivery risk and sediment attenuation. Thereafter, the mean Sediment Supply Index was divided by stream length for small catchments defined within the landscape to derive an index of sediment loading to streams. This index is used to identify priorities for management intervention across the landscape. The mean slope and sediment supply is used to develop buffer width recommendations for the streams draining the catchments, using a method developed by Karssies and Prosser (2001). Using the three indices in conjunction it is possible to make on-site and off-site erosion control recommendations as well as identify and exploit any natural features that can be utilized in erosion control. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2002

New Zealand, having large areas of hilly landscapes, is subject to the risk of soil erosion, and summer and autumn droughts that limit pasture growth, which in turn affects the livestock-based economy. The nitrogen and phosphorus input in fertilisers coupled with livestock excreta and soil disturbance impose a serious threat to downstream water quality. The planting of trees is one option used to decrease soil erosion, increase the quantity of forage and manage runoff. To date, research has mainly focused on wide spaced poplar trees for feed quality and their effects on understorey pasture growth. However, there is increasing interest in the use of densely planted willow and poplar for fodder purpose. The effects of young (< 5 yrs old) willow and poplar planted at close spacing on runoff, soil erosion, growth of understory pasture and nutrient losses have never been studied in New Zealand. Three field trials (two at Crop and Research Unit, Moginie, Manawatu and one at Riverside Farm, Masterton) were conducted between October 2004 and November 2006 that incorporated comparative establishment and growth of densely planted willow and poplar and their effects on soil moisture, runoff, sediment load and nutrient losses from grazed and fertilised farmland. It was concluded that densely planted willow and poplar (3-4 yrs) reduced total nitrogen (TN) and dissolved reactive phosphorus (DRP) by 47 % each and sediment load by 52 %. Young trees reduced surface runoff and soil moisture more as they aged. However, due to their deciduous nature willow and poplar were not effective in reducing surface runoff in winter and early spring. Sheep preferred camping under trees, especially in late spring and summer, and this led to greater deposition of dung and urine under trees than open pasture. Sheep grazing, especially in winter, significantly increased sediment and nutrient loads in runoff water. The N and P fertiliser application increased nutrient load in runoff water well above the threshold level required to initiate algal growth to create eutrophication. Densely planted willow and poplar significantly reduced understorey pasture growth by 23 % and 9 %, respectively, in their second year at Moginie, mainly due to shade, but coupled with soil moisture deficit in summer. The pasture growth in a willow browse block was 52 % of that in open pasture as a result of shade and differences in pasture species composition. Sheep browsing reduced willow leaf area significantly. Willow and poplar survival rates were similar (P > 0.05) after two years of establishment (100 % vs 90.5 %, respectively). However, willow grew faster than poplar in height (1.90 vs 1.35 m), stem diameter (43.5 vs 32.6 mm), canopy diameter (69 vs 34 cm) and number of shoots (8.7 vs 2.3) at the age of two years, respectively. The research clearly demonstrated that densely planted young willow and poplar trees can reduce runoff, sediment load and nutrient losses from farmland to freshwater, but shade and soil moisture can limit pasture growth under trees. It is recommended that willow and poplar should be planted at wide spacing on the whole farm to minimise loss of pasture. Where blocks of trees are necessary, such as willow browse blocks, sheep browsing can be used as a tool to reduce shade to improve pasture growth. Livestock access to riparian strips should be minimal to avoid livestock camping that can have deleterious effects on water quality.