Master of Science / Department of Biological & Agricultural Engineering / Naiqian Zhang / The primary objective of this research is to achieve automatic evaluation of the efficiency of using Trichogramma bourarachae for biological control of Cadra (=Ephestia) cautella by calculating the rate of parasitization. Cadra cautella is a moth feeding as a larva on dried fruit as well as stored nuts, seeds, and other warehouse foodstuffs. It attacks dates from ripening stages while on tree, throughout storage, and until consumption. These attacks cause significant qualitative and quantitative damages, which negatively affect dates’ marketability, resulting in economic losses. To achieve this research goal, tasks were accomplished by developing image processing algorithms for detecting, identifying, and differentiating between three Cadra cautella egg categories based on the success of Trichogramma parasitization against them. The egg categories were parasitized (black and dark red), fertile (unhatched yellow), and hatched (white) eggs. Color, intensity, and shape information was obtained from digital images of Cadra eggs after they were subjected to Trichogramma parasitization and used to develop detection algorithms. Two image processing methods were developed. The first method included segmentation and extractions of color and morphological features followed by watershed delineation, and is referred to as the "Watershed Method" (WT). The second method utilized the Hough Transformation to find circular objects followed by convolution filtering, and is referred to as the "Hough Transform Method" (HT). The algorithms were developed based on 2 images and then tested on more than 40 images. The WT and the HT methods achieved correct classification rates (CCRs) of parasitized eggs of 92% and 96%, respectively. Their CCRs of yellow eggs were 48% and 94%, respectively, while for white eggs the CCRs were 42% and 73%. Both methods performed satisfactorily in detecting the parasitized eggs, but the HT outperformed the WT in detecting the unparasitized eggs. The developed detection methods will enable automatic evaluation of biological control of Cadra (=Ephestia) cautella using Trichogramma bourarachae. Moreover, with few adjustments these methods can be used in similar applications such as detecting plant diseases in terms of presence of insects or their eggs.

O manejo nutricional de plantios de Eucalyptus é comprovadamente importante para o aumento da produtividade e da sustentabilidade da produção madeireira. Uma das principais formas de manejo nutricional da floresta é a fertilização mineral, que demanda grandes investimentos e necessita de um planejamento adequado. O conhecimento do valor e da escala da resposta à fertilização é essencial para estudos de investimento em práticas silviculturais. O método denominado de parcelas gêmeas possibilita a determinação da resposta à fertilização numa escala regional, em um curto período de tempo. O delineamento consiste na instalação e avaliação de blocos experimentais distribuídos em diversos locais. Estes blocos são constituídos por uma parcela testemunha, que normalmente são parcelas permanentes de inventário e uma parcela fertilizada, que recebe um regime intensivo de fertilização. O método das parcelas gêmeas foi utilizado neste estudo para determinar a resposta à fertilização de plantios clonais de eucalipto, e as relações desta resposta com variáveis edafoclimáticas e silviculturais. Um total de 131 blocos de parcelas gêmeas foi instalado em uma área de 34.540 hectares de plantios clonais de Eucalyptus urophylla, no estado de São Paulo, nos municípios de Mogi Guaçu, Brotas e São Simão. Os tratamentos foram avaliados por dois períodos consecutivos de 12 meses, totalizando 24 meses de avaliação. As parcelas fertilizadas apresentaram um crescimento médio 15% superior à média das parcelas testemunha. O incremento corrente anual médio das parcelas fertilizadas, foi de 31,6 Mg ha-1 ano-1 (64,2 m3 ha-1 ano-1), enquanto que nas parcelas testemunhas foi de 27,6 Mg ha-1 ano-1 (56,1 m3 ha-1 ano-1). A diferença destes incrementos revelou uma resposta à fertilização média de 4,0 Mg ha-1 ano-1 (8,1 m3 ha-1 ano-1). Plantios em solos com maior teor de areia e menores teores de nutrientes foram os que apresentaram as maiores médias de resposta à fertilização, de 8,5 Mg ha-1 ano-1 (16,9 m3 ha-1 ano-1). Os clones responderam de forma semelhante à fertilização e a resposta dos plantios mais velhos foi significativamente maior do que de plantios mais novos (1,7 Mg ha-1 ano-1 para cada ano de idade adicional). A resposta à fertilização correlacionou-se negativamente com o índice de sítio (base 7 anos), teores de argila e silte e com a maioria das variáveis químicas do solo. As variáveis químicas relacionadas às bases do solo, como soma de bases, saturação de bases, Ca, Mg e K, foram as que mais se correlacionaram com a resposta à fertilização. A resposta à fertilização correlacionou-se positivamente com a idade, teor de areia no solo e com a deficiência hídrica. Foi possível desenvolver modelos de predição da resposta à fertilização em função de variáveis químicas e físicas do solo e variáveis silviculturais. A técnica permitiu discriminar a necessidade, ou não, de fertilização por níveis categóricos distintos, como região, fazenda, solo e talhão, baseando-se, este último, no índice de sítio. Nas condições do estudo, concluiu-se que a resposta à fertilização foi maior em solos menos férteis, não diferiu entre clones e foi maior quanto maior a idade do plantio. / Nutrition management in Eucalyptus plantations is a key issue to increase productivity and sustainability of wood production. Mineral fertilization is the main procedure for managing forest nutrition, and it demands large amounts of investments and adequate planning. The understanding of the value and extension of the fertilization response is essential to the evaluation of investments in nutrition of commercial plantations. The twin plots design enables the determination of the fertilization response in a short period of time, in a landscape scale. This method entails the establishment of many pairs of plots, with one control and one treatment plot at each location. The control plot is the normal permanent plot of the inventory network, which measures the real productivity of the forest under the traditional company management. The nearby twinplot is under intensive management (high fertilization, weed and pest controls) in order to remove, or minimize, the constraints to forest productivity. A total of 131 blocks of twin plots were established in an area of 34,540 hectares of clonal plantations of Eucalyptus urophylla, located in the state of Sao Paulo, Brazil. All plots were re-measured in two consecutive periods of 12 months, for 24 months. Fertilized plots increased growth by 15% over control plots. The mean annual biomass increment of fertilized plots was 31,6 Mg ha-1 yr-1 (64,2 m3 ha-1 ano-1), while control plots was 27,6 Mg ha-1 yr-1 (56,1 m3 ha-1 ano-1). The difference between these increments showed a mean fertilization response of 4,0 Mg ha-1 yr-1 (8,1 m3 ha-1 ano-1). Twin plots located on sandier and less fertile soils averaged higher fertilization response by 8,5 Mg ha-1 yr-1 (16,9 m3 ha-1 ano-1). Clones responded similarly to fertilization, and older stands showed higher responses than younger stands (1,7 Mg ha-1 ano-1 for each additional year). Fertilization response correlated negatively with site index (base age 7), soil clay and silt content, and with most of the chemical soil attributes. Highest correlations to response were found in soil base nutrients (sum of bases, base saturation, Ca, Mg and K), age and site index. Fertilization response correlated positively with stand age, soil sand content and water deficit. Models for the prediction of fertilization response were developed based on stand, soil chemical and physical variables. The twin-plots method allowed the discrimination of the need for fertilization in different levels, like region, farm, soil and stand (based on the site index). Conclusions in this study were that fertilization response was higher in less fertile soils, was similar between clones and is higher in older than in younger plantations.

Este trabalho trata da organização de um algoritmo, sem preocupação com a linguagem de programação que possa ser utilizada, para desenvolver um método para o traçado da linha divisória de uma bacia hidrográfica, para aplicações em SIG. O método escolhido foi o de análise dos oitos pixels à volta de um pixel já pertencente ao divisor, constituindo uma variação do processo conhecido como D8 (determinístico dos oito vizinhos), que só é possível ser aplicado em sistemas do tipo raster. A partir dessa análise desenvolveu-se uma metodologia para a definição do próximo pixel que pertencerá ao divisor de águas da bacia. A avaliação do algoritmo foi feita utilizando-se um mapa fictício, criado para incluir as mais prováveis dificuldades encontradas na definição do divisor de uma bacia através de programa computacional. O traçado obtido, acompanhando as etapas lógicas do algoritmo, mostrou-se adequado quando comparado com a linha divisória da bacia traçada manualmente. Um mapa digitalizado a partir de rede local real é utilizado como exemplo de aplicação do algoritmo desenvolvido. / This work is about the organizing of an algorithm, without any regard with the programming language that may be used, in order to develop a method for delineation of watershed boundaries, for GIS applications. The method chosen was the analysis of eight pixels that surround another pixel belonging to the watershed, being a variation of the process known as D8 (deterministic of the eight neighbors), which can only be applied in raster systems. Considering this analysis, a methodology was developed for establishing the next pixel that will belong to the watershed. The algorithm evaluation was done with a fictitious map, created to include the most probable difficulties in establishing the divisor of a watershed through a computer program. The obtained line, following the logical steps of the algorithm, was suitable when compared with the dividing line of the watershed done manually. A digital map of a real place is used as an example of application of the developed algorithm.

Understanding the implications of climate change on streamflow regime is complex as changes in climate vary over space and time. However, a better understanding of the impact of climate change is required for identifying how stream ecosystems vulnerable to these changes, and ultimately to guide the development of robust strategies for reducing risk in the face of changing climatic conditions. Here I used physically based hydrologic modeling to improve understanding of how climate change may impact streamflow regimes and advance some of the cyberinfrastructure and GIS methodologies that support physically based hydrologic modeling by: (1) using a physically based model to examine the potential effects of climate change on ecologically relevant aspects of streamflow regime, (2) developing data services in support of input data preparation for physically based distributed hydrologic models, and (3) enhancing terrain analysis algorithms to support rapid watershed delineation over large area. TOPNET, a physically based hydrologic model was applied over eight watersheds across the U.S to assess the sensitivity and changes of the streamflow regime due to climate change. Distributed hydrologic models require diverse geospatial and time series inputs, the acquisition and preparation of which are labor intensive and difficult to reproduce. I developed web services to automate the input data preparation steps for a physically based distributed hydrological model to enable water scientist to spend less time processing input data. This input includes terrain analysis and watershed delineation over a large area. However, limitations of current terrain analysis tools are (1) some support only a limited set of specific raster and vector data formats, and (2) all that we know of require data to be in a projected coordinate system. I enhanced terrain analysis algorithms to extend their generality and support rapid, web-based watershed delineation services. Climate change studies help to improve the scientific foundation for conducting climate change impacts assessments, thus building the capacity of the water management community to understand and respond to climate change. Web-based data services and enhancements to terrain analysis algorithms to support rapid watershed delineation will impact a diverse community of researchers involved terrain analysis, hydrologic and environmental modeling.

This study integrated remotely sensed data, geographic information system (GIS), and classification tree-based modeling to delineate ecological units for the Ashley National Forest. Data points , provided by the Ashley National Forest, with a known location and dominant vegetation type, were related to data layers that were determined to be helpful in a landtype classification. These layers included elevation, slope, aspect, potential solar irradiation, precipitation, geology, basins, Landsat thematic mapper (TM) bands 3, 4, 5, and 6, and basic land cover. These points, with their related information, were then used to train the tree-based model for landtype classification. This resulted in a set of rules, in the form of a binary decision tree, that could be applied to the entire study area. After the landtype classification was obtained, it was cross-classified with geology to produce a landtype association layer. This resulting data layer was compared to an existing landtype association map and it was determined, by cross-tabulation, that the two classifications identified many of the same patterns.

Maintaining the ecological health of streams is vital for sustainable water resources management. Streamflow is a primary factor influencing the structure and function of ecological communities. A quantitative understanding of how stream biota respond to variation in streamflow is required for stream bioassessment. This dissertation focuses on quantifying relationships between streamflow regime and stream macroinvertebrate richness and composition. The contribution comprises statistical models that predict stream macroinvertebrate class from streamflow regime and predict streamflow regime from watershed attributes, and a tool that helps derive watershed attribute variables used in these models. The dissertation is a collection of three papers. In the first paper 12 variables were used to represent streamflow regime at 543 sites in the western US. Principal component analysis (PCA) and K-means clustering were used to obtain statistically independent factors and streamflow regime classes. We examined the relationship between these characterizations of streamflow and macroinvertebrate richness and composition at 63 of the 543 sites where there was also biological data. This analysis identified specific aspects of the streamflow regime that were useful in predicting macroinvertebrate richness and composition and that have potential application in classification-based bioassessment and management. A regional-scale study such as this requires tools for efficiently delineating watersheds and deriving their attributes. Paper two presents a multiple watershed delineation tool that addresses issues such as a) incorrectly positioned outlets and b) large Digital Elevation Models. This tool has capabilities to delineate stream networks with the threshold that determines drainage density being objectively determined so that the resulting networks adhere to geomorphological stream network laws. It also derives a suite of geomorphological watershed attributes that were used in prediction models in paper three. In paper three, we developed statistical models to predict streamflow regime class from watershed attributes. Four popular statistical methods were used and the uncertainty associated with class predictions for each method was quantified. Paper three also identified the watershed attributes that were most important for discriminating streamflow regime classes.

DEM analysis to delineate the stream network and its associated subwatersheds are the primary steps in the raster-based parameterization of watersheds. There are two widely used methods for delineating subwatersheds. One of these is the Upstream Catchment Area (UCA) method. The UCA method employs a user specified threshold value of upstream catchment area to delineate subwatersheds from the extracted network of streams. The other common technique is the nodal method. In this approach, subwatersheds are initiated at stream network nodes, where nodes occur at the upstream starting point of streams and at the point of intersection of streams in the network. The UCA approach and the Nodal approach do not permit watershed initiation at points of specific interests. They also fail to explicitly recognize drainage features other than single channel reaches. That is, they exclude water bodies, wetlands, braided channels and other important hydrologic features. TOPAZ (TOpographic PArameteriZation) [Garbrecht and Martz, 1992], is a typical program for raster based, automated drainage analysis. It initiates subwatersheds at source points and at points of intersection of drainage channels. TOPAZ treats lakes as spurious depressions arising out of errors in DEM, and removes them. This research addresses one important limitation of the currently used modeling techniques and tools. It adds the capability to initiate watershed delineation at points of specific interest other than junction and source points in the delineated networks from the Digital Elevation Models (DEMs). The research project evaluates qualitative and quantitative aspects of a new Object Oriented data structure and process model for raster format data analysis in spatial hydrology. The concept of incorporating a user-specified analysis in extraction and parameterization of watersheds is based on the need to have a tool to allow for studies specific to certain points in the stream network including gauging stations. It is also based on the need for an improved delineation of hydrologic features (water bodies) in hydrologic modeling. The research project developed an interface module for TOPAZ [Garbrecht and Martz, 1992] to offset the aforementioned disadvantages of the subwatershed delineation techniques. The research developed an internal hybrid, raster-based, Object Oriented data structure and processing model similar to that of vector data type. The new internal data structure permits further augmentation of the software tool. This internal data structure and algorithms provide an improved framework for discretization of the important hydrologic entities (water bodies) and the capability of extracting homogenous hydrological subwatersheds.

DEM analysis to delineate the stream network and its associated subwatersheds are the primary steps in the raster-based parameterization of watersheds. There are two widely used methods for delineating subwatersheds. One of these is the Upstream Catchment Area (UCA) method. The UCA method employs a user specified threshold value of upstream catchment area to delineate subwatersheds from the extracted network of streams. The other common technique is the nodal method. In this approach, subwatersheds are initiated at stream network nodes, where nodes occur at the upstream starting point of streams and at the point of intersection of streams in the network. The UCA approach and the Nodal approach do not permit watershed initiation at points of specific interests. They also fail to explicitly recognize drainage features other than single channel reaches. That is, they exclude water bodies, wetlands, braided channels and other important hydrologic features. TOPAZ (TOpographic PArameteriZation) [Garbrecht and Martz, 1992], is a typical program for raster based, automated drainage analysis. It initiates subwatersheds at source points and at points of intersection of drainage channels. TOPAZ treats lakes as spurious depressions arising out of errors in DEM, and removes them. This research addresses one important limitation of the currently used modeling techniques and tools. It adds the capability to initiate watershed delineation at points of specific interest other than junction and source points in the delineated networks from the Digital Elevation Models (DEMs). The research project evaluates qualitative and quantitative aspects of a new Object Oriented data structure and process model for raster format data analysis in spatial hydrology. The concept of incorporating a user-specified analysis in extraction and parameterization of watersheds is based on the need to have a tool to allow for studies specific to certain points in the stream network including gauging stations. It is also based on the need for an improved delineation of hydrologic features (water bodies) in hydrologic modeling. The research project developed an interface module for TOPAZ [Garbrecht and Martz, 1992] to offset the aforementioned disadvantages of the subwatershed delineation techniques. The research developed an internal hybrid, raster-based, Object Oriented data structure and processing model similar to that of vector data type. The new internal data structure permits further augmentation of the software tool. This internal data structure and algorithms provide an improved framework for discretization of the important hydrologic entities (water bodies) and the capability of extracting homogenous hydrological subwatersheds.

No description available.

The automated Tree Identification and Delineation Algorithm (TIDA) was developed for application to high spatial resolution digital imagery of Australian native eucalypt forest. The algorithm is based on contiguous, threshold-based spatial clustering of pixels and was designed to cope with the complex asymmetric crowns typical of eucalypts. / To facilitate systematic algorithm evaluation, a forest scene simulation model was created for the simulation of visually realistic remotely sensed images. The model is based on the principles of ray-tracing and the geOll1etric description of scene objects and background. The model simulates the appearance of a forest scene viewed and illuminated from specific directions and under known atmospheric conditions. The distinctive 'modular' structure of eucalypts was represented by modelling crowns as small (branch-scale) spheroids distributed over a larger spheroidal envelope. / Using the simulation model, TIDA performance was evaluated in terms of forest structure (canopy cover, crown cover and canopy structural variability) and the remote sensing environment (view zenith angle, solar zenith angle and aerosol optical thickness). Prior to the evaluation, a methodology was developed for objectively estimating the optimum spatial resolution for TIDA application in a given image. The methodology was based on incremental Gaussian smoothing and exploited TIDA's sensitivity to changes in image spatial resolution. This process demonstrated the importance of individual crown cover, rather than crown size, as the main factor determining the optimum spatial resolution for tree delineation. / Results indicate that TIDA is most suited for application in forests with high canopy cover and high crown cover. The structural complexity of forest canopies, represented by the diameter and overlap of crowns and tree height, had a relatively small impact on TIDA performance. Increasing view zenith angle consistently caused a decrease in TIDA performance. A small phase angle between the sun and sensor produces optimum TIDA performance when both canopy and crown cover is high. As crown or canopy cover decrease, high positive and negative sun zenith angles yield superior TIDA results by decreasing the brightness of the background relative to the canopy and improving the identification of tree peaks. For both dense and sparse canopies, back-scattered radiation from the forest canopy was more suited to automated tree crown delineation than forward-scattered radiation. Imagery acquired under an optically thick atmosphere was found to increase TIDA performance compared to scene illumination under strong direct light. The advantage stemmed from a strengthening of the relationship between geometric and radiometric crown shape. / Through an awareness of limitations imposed by the remote sensing environment, the potential for manipulation of image characteristics, and preferential selection of acquisition conditions, TIDA performance can be optimised to suit various structural forest types. Canopy cover, crown cover, view zenith angle, sun zenith angle, background brightness and image spatial resolution are key criteria in assessing the suitability of automated tree crown delineation as an image interpretation procedure.