Academic literature on the topic 'Index of Stream Condition'

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Journal articles on the topic "Index of Stream Condition"

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Yirigui, Lee, and Nejadhashemi. "Multi-Scale Assessment of Relationships between Fragmentation of Riparian Forests and Biological Conditions in Streams." Sustainability 11, no. 18 (September 16, 2019): 5060. http://dx.doi.org/10.3390/su11185060.

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Due to anthropogenic activities within watersheds and riparian areas, stream water quality and ecological communities have been significantly affected by degradation of watershed and stream environments. One critical indicator of anthropogenic activities within watersheds and riparian areas is forest fragmentation, which has been directly linked to poor water quality and ecosystem health in streams. However, the true nature of the relationship between forest fragmentation and stream ecosystem health has not been fully elucidated due to its complex underlying mechanism. The purpose of this study was to examine the relationships of riparian fragmented forest with biological indicators including diatoms, macroinvertebrates, and fish. In addition, we investigated variations in these relationships over multiple riparian scales. Fragmentation metrics, including the number of forest patches (NP), proportion of riparian forest (PLAND), largest riparian forest patch ratio (LPI), and spatial proximity of riparian forest patches (DIVISION), were used to quantify the degree of fragmentation of riparian forests, and the trophic diatom index (TDI), benthic macroinvertebrates index (BMI), and fish assessment index (FAI) were used to represent the biological condition of diatoms, macroinvertebrates, and fish in streams. PLAND and LPI showed positive relationships with TDI, BMI, and FAI, whereas NP and DIVISION were negatively associated with biological indicators at multiple scales. Biological conditions in streams were clearly better when riparian forests were less fragmented. The relationships of NP and PLAND with biological indicators were stronger at a larger riparian scale, whereas relationships of LPI and DIVISION with biological indicators were weaker at a large scale. These results suggest that a much larger spatial range of riparian forests should be considered in forest management and restoration to enhance the biological condition of streams.
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Maloney, Kelly Oliver, Daren Milo Carlisle, Claire Buchanan, Jennifer Lynn Rapp, Samuel Hess Austin, Matthew Joseph Cashman, and John André Young. "Linking Altered Flow Regimes to Biological Condition: an Example Using Benthic Macroinvertebrates in Small Streams of the Chesapeake Bay Watershed." Environmental Management 67, no. 6 (March 12, 2021): 1171–85. http://dx.doi.org/10.1007/s00267-021-01450-5.

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AbstractRegionally scaled assessments of hydrologic alteration for small streams and its effects on freshwater taxa are often inhibited by a low number of stream gages. To overcome this limitation, we paired modeled estimates of hydrologic alteration to a benthic macroinvertebrate index of biotic integrity data for 4522 stream reaches across the Chesapeake Bay watershed. Using separate random-forest models, we predicted flow status (inflated, diminished, or indeterminant) for 12 published hydrologic metrics (HMs) that characterize the main components of flow regimes. We used these models to predict each HM status for each stream reach in the watershed, and linked predictions to macroinvertebrate condition samples collected from streams with drainage areas less than 200 km2. Flow alteration was calculated as the number of HMs with inflated or diminished status and ranged from 0 (no HM inflated or diminished) to 12 (all 12 HMs inflated or diminished). When focused solely on the stream condition and flow-alteration relationship, degraded macroinvertebrate condition was, depending on the number of HMs used, 3.8–4.7 times more likely in a flow-altered site; this likelihood was over twofold higher in the urban-focused dataset (8.7–10.8), and was never significant in the agriculture-focused dataset. Logistic regression analysis using the entire dataset showed for every unit increase in flow-alteration intensity, the odds of a degraded condition increased 3.7%. Our results provide an indication of whether altered streamflow is a possible driver of degraded biological conditions, information that could help managers prioritize management actions and lead to more effective restoration efforts.
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Kakore, Blandina Genes, Md Mamun, Sang-Jae Lee, and Kwang-Guk An. "Land-Use Pattern as a Key Factor Determining the Water Quality, Fish Guilds, and Ecological Health in Lotic Ecosystems of the Asian Monsoon Region." Water 14, no. 17 (September 5, 2022): 2765. http://dx.doi.org/10.3390/w14172765.

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Land-use patterns influence water quality in lotic ecosystems worldwide; consequently, deteriorating water quality affects fish communities and composition and the ecological health of water bodies. This study aimed to evaluate how land use, stream order, and elevation regulate water quality and ecological health in 64 streams based on the following four land cover types: namely, forest, agriculture, urban upstream, and urban downstream regions. Spatial analysis revealed that urban downstream areas had higher nutrient concentrations [total phosphorus (TP) as follows: 117 µg/L; total nitrogen (TN): 5.57 mg/L] and organic pollutants [chemical oxygen demand (COD): 7.71] than other regions. Empirical analysis indicated that TP (R2 = 0.46) had a high relation with chlorophyll-a (Chl-a) compared to TN (R2 = 0.23) and TN:TP (R2 = 0.20). Elevation, stream order, and monsoon season significantly impact nutrients, organic matter, suspended particles, ionic content, and algal chlorophyll concentrations. The index of biotic integrity (IBI) was significantly positively correlated with elevation (R2 = 0.387), indicating that forest streams (high elevation) had better water quality and ecological health than lower-elevation streams. The proportion of insectivore species shows a significant negative relationship with biological oxygen demand (BOD) (R2 = 0.123) and TP (R2 = 0.155). The multi-metric index of biotic integrity (IBI) model suggested that the ecological health of forest streams was in fair condition. In contrast, agricultural streams were in poor condition, and urban upstream and downstream were in very poor conditions. The outcomes of this study indicated that land-use patterns and elevation largely regulate the water quality and ecological health of the streams.
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Collier, Kevin J., and Anthony R. Olsen. "Monitoring network-design influence on assessment of ecological condition in wadeable streams." Marine and Freshwater Research 64, no. 2 (2013): 146. http://dx.doi.org/10.1071/mf12267.

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We investigated outcomes of three monitoring networks for assessing ecological character and condition of wadeable streams, Waikato region, New Zealand. Site selection was based on professional judgment, stratification within categories of watershed characteristics, or on using an unequal-probability survey design. The professional-judgment network, stratified network and all site analyses included more ≥4th-order streams than for the probability-network survey-design estimates Professional-judgment and stratified network sites and survey-design analyses incorporated higher-quality catchments with coarser substrates. Cumulative frequency distributions indicated that the stratified and/or judgmental networks yielded fewer taxa than did the probability network, and that the stratified network provided lower estimates of the macroinvertebrate community index (MCI). Compared with the probability-network survey-design analysis, the stratified network site analysis underestimated percentage stream length classed as ‘Excellent’ by the quantitative MCI, and the professional-judgment site and survey-design analyses overestimated the percentage classed ‘Fair’ by the average score per metric. We conclude that deriving reliable estimates of wadeable stream character and condition requires (1) clearly defining and quantifying the target population for which inferences will be drawn, (2) accounting for probability of site selection and (3) optimising spatial representation across dominant stressor gradients.
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Yirigui, Yirigui, Sang-Woo Lee, A. Pouyan Nejadhashemi, Matthew R. Herman, and Jong-Won Lee. "Relationships between Riparian Forest Fragmentation and Biological Indicators of Streams." Sustainability 11, no. 10 (May 20, 2019): 2870. http://dx.doi.org/10.3390/su11102870.

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Anthropogenic activities, such as land use and land cover modifications in riparian areas, can alter the degree of fragmentation of riparian vegetation, lead to the degradation of stream habitats, and affect biological communities in the streams. The characteristics of the riparian forests can modify the condition of stream environments and the transporting mechanisms of materials, sediments, nutrients, and pollutants loaded from the watersheds. This study aimed to examine the relationships between forest fragmentation and three biological indicators of trophic diatom, benthic macroinvertebrate, and the fish assessment in the Nakdong River, Korea. Eighty-nine biological assessment sampling sites in the National Aquatic Ecological Monitoring Program of South Korea were identified. For each sampling site, riparian forest data within a 500 m radius were extracted from national LULC using GIS to compute fragmentation metrics using FRAGSTATS software. Four fragmentation metrics—number of forest patches, percentage of riparian forest cover (PLAND), largest riparian forest patch index (LPI), and riparian forest division index (DIVISION)—were correlated with the biological indicators. Also, due to severe spatial autocorrelation among observations, the fragmentation metrics and stream environmental variables were regressed to biological indicators using regression tree analysis. Our results indicate that the biological indicators were significantly associated with most forest fragmentation metrics. We found positive correlations of PLAND and LPI with biological indicators, whereas DIVISION was negatively correlated with biological indicators. Both correlation and regression tree analyses revealed that the biological conditions of streams were likely to be better if riparian forests are less fragmented. Particularly, stronger relationships were revealed between macroinvertebrates and fish with the fragmentation metrics of riparian forests than with benthic diatoms. However, these relationships varied with elevation, stream size, and slope conditions. The results of this study reinforced the importance of including riparian forests in the planning, restoration, and management of stream environments. These results also suggested that planners and managers may need to consider different strategies for different stream environments and topographic characteristics in managing riparian forests.
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Donatich, Sara, Barbara Doll, Jonathan Page, and Natalie Nelson. "Can the Stream Quantification Tool (SQT) Protocol Predict the Biotic Condition of Streams in the Southeast Piedmont (USA)?" Water 12, no. 5 (May 22, 2020): 1485. http://dx.doi.org/10.3390/w12051485.

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In some states, the Stream Quantification Tool (SQT) has been adopted to quantify functional change of stream mitigation efforts. However, the ability of the SQT protocol to predict biological function and uphold the premise of the Stream Functions Pyramid (Pyramid) remains untested. Macroinvertebrate community metrics in 34 headwater streams in Piedmont, North Carolina (NC, USA) were related to NC SQT protocol (version 3.0) factors and other variables relevant to ecological function. Three statistical models, including stepwise, lasso, and ridge regression were used to predict the NC Biotic Index (NCBI) and Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness using two datasets: 21 SQT variables and the SQT variables plus 13 additional watershed, hydraulic, geomorphic, and physicochemical variables. Cross-validation revealed that stepwise and ridge outperformed lasso, and that the SQT variables can reasonably predict biology metrics (R2 0.53–0.64). Additional variables improved prediction (R2 0.70–0.88), suggesting that the SQT protocol is lacking metrics important to macroinvertebrates. Results moderately support the Pyramid: highly predictive ridge models included metrics from all levels, while highly predictive stepwise models included metrics from higher levels, and not watershed hydrology. Reach-scale metrics were more important than watershed hydrology, providing encouragement for projects limited by watershed condition.
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Myers, Thomas J., and Sherman Swanson. "AQUATIC HABITAT CONDITION INDEX, STREAM TYPE, AND LWESTOCK BANK DAMAGE IN NORTHERN NEVADA." Journal of the American Water Resources Association 27, no. 4 (August 1991): 667–77. http://dx.doi.org/10.1111/j.1752-1688.1991.tb01468.x.

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Urdánigo, Juan, Karla Pérez, Elian Intriago, Gabriela Arriaga, Solange Zambrano, and Oscar Prieto. "Bioindicators of water quality with different riparian cover in the Guapara micro watershed, Ecuador." Revista de la Facultad de Agronomía, Universidad del Zulia 39, no. 4 (November 24, 2022): e223952. http://dx.doi.org/10.47280/revfacagron(luz).v39.n4.07.

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Agricultural activities produce changes in the margins of the stream banks, causing disturbances in water quality, and in the assemblage of aquatic insect communities. The objective of this research is to evaluate the changes in the structure and composition of the aquatic macroinvertebrate community, and physicochemical variables in relation to the land use of the Guapara river, Cotopaxi province, Ecuador. Samplings were conducted during the rainy season (December to February 2018-2019) in three streams with different riparian cover: agricultural, native forest, and forest plantations, where samples of aquatic insects and physicochemical parameters were collected in situ. A total of 461 aquatic insects corresponding to 7 orders and 25 families were collected. In general, the highest abundance in order and family was presented by Ephemeroptera with 34 %, and Leptophlebiidae with 21 % respectively. According to the Ephemeroptera, Plecoptera Trichoptera (EPT) index, the highest ecological condition was found in streams with native forest cover, and forest plantations respectively, and decreased in the stream with agricultural cover; while BMWP-Cr indicated water contamination in the three streams. Hydrobiosidae (Trichoptera) were associated with high turbidity values; while Gerridae (Hemiptera) were associated with high dissolved oxygen concentrations; in addition, Ptilodactylidae (Coleoptera) preferred the Q1-CA, and Q3-CF conditions, while Leptophlebiidae (Ephemeroptera) were associated with the stream of native forest. A negative influence of agricultural activity on the physicochemical parameters of the water and on the structure of the aquatic insect community assemblage was evidenced.
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Wu, J. Y., J. R. Thompson, R. K. Kolka, K. J. Franz, and T. W. Stewart. "Using the Storm Water Management Model to predict urban headwater stream hydrological response to climate and land cover change." Hydrology and Earth System Sciences 17, no. 12 (December 3, 2013): 4743–58. http://dx.doi.org/10.5194/hess-17-4743-2013.

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Abstract. Streams are natural features in urban landscapes that can provide ecosystem services for urban residents. However, urban streams are under increasing pressure caused by multiple anthropogenic impacts, including increases in human population and associated impervious surface area, and accelerated climate change. The ability to anticipate these changes and better understand their effects on streams is important for developing and implementing strategies to mitigate potentially negative effects. In this study, stream flow was monitored during April–November (2011 and 2012), and the data were used to apply the Storm Water Management Model (SWMM) for five urban watersheds in central Iowa, USA, representing a gradient of percent impervious surface (IS, ranging from 5.3 to 37.1%). A set of three scenarios was designed to quantify hydrological responses to independent and combined effects of climate change (18% increase in precipitation), and land cover change (absolute increases between 5.2 and 17.1%, based on separate projections of impervious surfaces for the five watersheds) for the year 2040 compared to a current condition simulation. An additional set of three scenarios examined stream response to different distributions of land cover change within a single watershed. Hydrological responses were quantified using three indices: unit-area peak discharge, flashiness (R-B Index; Richards–Baker Index), and runoff ratio. Stream hydrology was strongly affected by watershed percent IS. For the current condition simulation, values for all three indices were five to seven times greater in the most developed watershed compared to the least developed watershed. The climate change scenario caused a 20.8% increase in unit-area peak discharge on average across the five watersheds compared to the current condition simulation. The land cover change scenario resulted in large increases for all three indices: 49.5% for unit-area peak discharge, 39.3% for R-B Index, and 73.9% for runoff ratio, on average, for the five watersheds. The combined climate and land cover change scenario resulted in slight increases on average for R-B Index (43.7%) and runoff ratio (74.5%) compared to the land cover change scenario, and a substantial increase, on average, in unit area peak discharge (80.1%). The scenarios for different distributions of land cover change within one watershed resulted in changes for all three indices, with an 18.4% increase in unit-area peak discharge for the midstream scenario, and 17.5% (downstream) and 18.1% (midstream) increases in R-B Index, indicating sensitivity to the location of potential additions of IS within a watershed. Given the likelihood of increased precipitation in the future, land use planning and policy tools that limit expansion of impervious surfaces (e.g. by substituting pervious surfaces) or mitigate against their impacts (e.g. by installing bioswales) could be used to minimize negative effects on streams.
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Henriques-Oliveira, Ana Lucia, Jorge Luiz Nessimian, and Darcílio Fernandes Baptista. "Diversity and composition of Trichoptera (Insecta) larvae assemblages in streams with different environmental conditions at Serra da Bocaina, Southeastern Brazil." Acta Limnologica Brasiliensia 27, no. 4 (December 2015): 394–410. http://dx.doi.org/10.1590/s2179-975x3215.

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Abstract: Aim The goal of this study is to examine the composition and richness of caddisfly assemblages in streams at the Serra da Bocaina Mountains, Southeastern Brazil, and to identify the main environmental variables, affecting caddisfly assemblages at the streams with different conditions of land use. Methods The sampling was conducted in 19 streams during September and October 2007. All sites were characterized physiographically by application of environmental assessment protocol to Atlantic Forest streams and by some physical and chemical parameters. Of the 19 streams sampled, six were classified as reference, six streams as intermediate (moderate anthropic impact) and seven streams as poor (strong anthropic impact). In each site, a multi-habitat sampling was taken with a kick sampler net. The sample was composed by 20 units, each one corresponded to 1 m2 of collected substrate, corresponding 20 m2 of sampling area. The material was placed in a plastic container (500 µm of mesh), washed, homogenized and sub-sampled. For each stream, 6 subsamples were randomly sorted. Results Were collected 2,113 caddisfly larvae, belonging to 12 families and 28 genera. Hydropsychidae and Leptoceridae were the most abundant families, and Smicridea was the most abundant genus. Sorensen’s index results showed that the streams studied were grouped according to environmental integrity. The Indicator Species Analysis showed only characteristic taxa to reference streams. Canonical Correspondence Analysis showed that caddisfly assemblage was strongly influenced by nitrate concentration, pH and condition of riparian vegetation. Multiple regression analysis indicated significant correlations to five genera with some environmental parameters, besides total abundance of Trichoptera. Conclusions Ours results showed that degree of environmental impact, mainly the nitrate concentration, pH, and condition of cover vegetation acted as a major factor in determining the Trichoptera assemblages present in the stream of the Serra da Bocaina, separating streams along an environmental gradient.
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Dissertations / Theses on the topic "Index of Stream Condition"

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Hilton, Gene T. "A seasonality study of the West Virginia stream condition index." Huntington, WV : [Marshall University Libraries], 2004. http://www.marshall.edu/etd/descript.asp?ref=494.

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Elias, Carmen Lopes. "Effect of global changes and spatial scale on diatom communities of temperate rivers: dealing with implications in bioassessment." Doctoral thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/22393.

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Doutoramento em Biologia
Diatoms are generally the most frequent and abundant algae in streams and are known by their responsiveness to changes in the environmental conditions of streams. Diatoms are frequently the only biological quality element representative of the aquatic flora in small streams. As a result, diatoms are nowadays a mandatory biological element in the evaluation of the ecological quality of European rivers, according to the Water Framework Directive. Nevertheless, there is still a relative lack of knowledge of key effects of global changes and spatial scale on diatoms. To bridge this gap, this work aims to study the effect of relevant global changes as well as spatial scale on diatom communities of temperate rivers and to deal with its implications in bioassessment. The relevant global changes were assessed in streams from the central Portuguese littoral region which is highly populated and suffers from high anthropogenic impacts. The effect of spatial scale on diatom communities was investigated by a laboratorial experiment (mesocosm experiment) and by using diatom data from temperate regions of the United States of America and Australia. In order to achieve the main aim, three global questions were raised: (1) How to deal with the historical anthropogenic influences in the bioassessment?; (2) Are extreme events due to climatic changes reflected in diatom communities? A comparison with macroinvertebrate communities; (3) How are diatom communities influenced at the spatial scale (small-scale: habitats; large-scale: inter-continental). A strong anthropogenic influence on the streams and rivers of the Portuguese littoral region was confirmed as well as the lack of true reference sites. Sites in the Least Disturbed Condition (LDC) had considerable high nutrient concentrations. As the strong anthropogenic pressures (e.g., alteration of the riparian vegetation, morphological condition and sediment load) prevented an adequate definition of reference conditions for streams in this area an alternative procedure to define suitable reference conditions was investigated, consisting of a combination of modelling and filter approach. This procedure is suitable to deal with the implications of global changes on diatom and on macroinvertebrate communities. The communities observed in the different streams were less homogeneous than those predicted for the same streams under reference conditions (i.e., through the filter approach), as would be expected in sites having variable levels of anthropogenic change. Along with the development of this new approach a new multimetric diatom index was developed. This index produced strong correlations with the selected pressures, providing a more comprehensive assessment of biological quality than the Indice de Polluosensibilité Spécifique (IPS) officially adopted for Portugal. To answer the second global question a smaller set of streams were used within the Portuguese littoral region that were affected by an unusual drought event that lead to the complete drying of the stream channels. Diatoms, as well as macroinvertebrates, were affected by the drought event considering trait proportions, community’s composition and bioassessment classifications. However, the diatom communities had a faster recovery response than macroinvertebrates. The type of substrate – hard and soft –representing the small spatial scale affected diatom communities by changing its composition and trait proportions but not water quality classification in a mesocosm experiment. However, the differences found in the epipsammic and epilithic diatom communities in the streams that were used to answer the first global question were more evident than those found in the mesocosm experiment. In fact, with the mesocosm results, and under the same physical and chemical conditions the IPS differences between substrates disappeared contrasting with the differences that were found in the streams. Additionally, the diatom communities were different between continents with the same type of climate, suggesting that diatom communities are also influenced at the large-scale (even at the order level). Therefore, constraints other than climate are likely to have contributed to the inter-continental differences in diatom community composition found at all taxonomical levels (e.g., geology, historical biogeographic processes and hydrology). On the whole, the results obtained during this study bring new information and new approaches to deal with the bioassessment. However, some more work must be done in order to investigate e.g., based in the global warming predictions, the effects of the temperature increase, on the water quality assessment based on diatom communities.
As diatomáceas são as algas que se encontram mais frequentemente e em maior abundância em cursos de água doce. São conhecidas pela capacidade dos diferentes taxa responderem a variações das condições ambientais dos rios e por serem frequentemente o único elemento de qualidade biológica representativo da flora aquática em pequenos rios e ribeiras. Em consequência destas características, e de acordo com a Directiva Quadro da Água, as diatomáceas são presentemente um dos elementos biológicos obrigatórios na avaliação da qualidade ecológica dos rios europeus. No entanto, ainda existe algum desconhecimento acerca dos efeitos das alterações globais e da escala espacial nas diatomáceas. Para colmatar esta lacuna, o presente trabalho tem como objetivo estudar o efeito de alterações globais relevantes e da escala espacial nas comunidades de diatomáceas de rios temperados assim como estudar a melhor forma de lidar com as suas implicações na biomonitorização. O efeito das alterações globais foi estudado em rios e ribeiras da região centro litoral de Portugal continental dado tratar-se de uma região densamente povoada e sujeita a impactos antropogénicos significativos. O efeito da escala espacial nas comunidades de diatomáceas foi investigado através de uma experiência laboratorial (mesocosmos) e também com recurso a informação estatística de comunidades de diatomáceas de várias regiões temperadas, incluindo as costas ocidentais dos Estados Unidos da América e da Austrália. De modo atingir o objetivo principal deste trabalho, três questões globais foram colocadas: (1) Como lidar com as influências antrópicas históricas na biomonitorização?; (2) Será que as comunidades de diatomáceas reflectem os eventos extremos causados pelas alterações climáticas? Uma comparação com as comunidades de macroinvertebrados; (3) Como são as comunidades de diatomáceas influenciadas pela escala espacial (pequena escala: habitats; grande escala: inter-continental). Verificou-se uma influência antropogénica considerável nos rios e ribeiras da região centro litoral de Portugal continental assim como a inexistência de verdadeiros locais de referência. Mesmo os locais considerados como estando em condições de menor perturbação apresentaram concentrações de nutrientes consideravelmente elevadas na água. Uma vez que as fortes pressões antropogénica (p.e., alteração da vegetação ripária, condição morfológica e carga de sedimentos) não permitiram o estabelecimento de condições de referência adequadas para os rios desta região, foi proposto um procedimento alternativo baseado numa combinação de dois métodos – modelação e filtros ambientais. A aplicação deste procedimento na definição de condições de referência revelou-se útil para lidar com os efeitos das alterações globais na biomonitorização com recurso a comunidades de diatomáceas e macroinvertebrados. De facto, como seria de esperar, as comunidades observadas em rios sujeitos a alterações antropogénicas revelaram-se menos homogéneas do que as previstas em condições de referência para esses mesmos rios, i.e., através da aplicação dos referidos filtros ambientais. Em conjunto com o desenvolvimento deste novo procedimento, foi também proposto um novo índice multimétrico de diatomáceas. Este novo índice revelou-se fortemente correlacionado com as pressões selecionadas, fornecendo uma avaliação da qualidade biológica mais abrangente do que o índice oficial adotado por Portugal, o Indice de Polluosensibilité spécifique (IPS). Para responder à segunda questão global apenas um subconjunto de ribeiras da região litoral de Portugal foi selecionado, o qual engloba as ribeiras cujos leitos secaram durante uma vaga de calor invulgar que ocorreu em Portugal em 2011/2012. Verificou-se que, de facto, quer as comunidades de diatomáceas quer de macroinvertebrados foram afetadas pelo evento de seca extrema tendo-se observado alterações ao nível das proporções de traits, composição e a classificação da qualidade biológica. No entanto, as diatomáceas apresentaram uma recuperação significativamente mais rápida que os macroinvertebrados. Os tipos de substratos usados na experiência de mesocosmos realizada neste trabalho (duro vs. macio; pequena escala espacial) também mostraram afetar as comunidades de diatomáceas, uma vez que houve diferenças quer na sua composição quer nas proporções de traits. Esta resposta ao tipo de substrato foi mais evidente em condições físico-químicas controladas do que aquela sugerida pelas diferenças entre as comunidades epipsâmicas e epilíticas dos rios monitorizados neste trabalho. Não obstante, durante a experiência de mesocosmos verificou-se que ao nível de IPS as diferenças entre substratos não eram relevantes quando comparadas com as que se haviam verificado nos rios. As diferenças observadas entre as comunidades de diatomáceas dos vários continentes (Europa, América e Austrália) sugerem que variações ao nível da grande escala também ocasionam diferenças nas comunidades, apesar de influenciados pelo mesmo tipo de clima. Isto sugere que outros factores para além do clima (p.e., geologia, processos biogeográficos históricos e hidrologia) podem ter contribuído para as diferenças inter-continentais verificadas ao nível da composição das comunidades de diatomáceas, a todos os níveis taxonómicos estudados. De um modo geral, os resultados obtidos durante este estudo trazem novas informações e novas abordagens para lidar com a biomonitorização. No entanto, mais trabalho será necessário a fim de investigar, por exemplo, os efeitos do aumento da temperatura previstos devido ao aquecimento global na avaliação da qualidade da água com base em comunidades de diatomáceas.
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Ffolliott, Peter F. "Snowpack Density: An Index of Snowpack Condition." Arizona-Nevada Academy of Science, 1985. http://hdl.handle.net/10150/296382.

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From the Proceedings of the 1985 Meetings of the Arizona Section - American Water Resources Association and the Hydrology Section - Arizona-Nevada Academy of Science - April 27, 1985, Las Vegas, Nevada
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Johnson, Laura Young. "Evaluation of Bureau of Land Management Protocols for Monitoring Stream Condition." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/45202.

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The goal of the Aquatic Indicators of Land Condition (AILC) project is to develop analytical tools that integrate land condition information with stream condition for improved watershed management within the United States Bureau of Land Management (BLM). Based on the goal of the AILC, two objectives for this study were: to determine the effect of four GIS-derived distance measurements on potential relationships between common BLM landscape stressors (mining and grazing) and changes in benthic macroinvertebrate community structure; and to assess the effectiveness of individual questions on a commonly-used Bureau-wide qualitative stream assessment protocol, the proper functioning condition (PFC) assessment. The four GIS distance measurements assessed for biotic relevance included: straight-line distance, slope distance, flow length, and travel time. No significant relationships were found between the measured distance to stressor and macroinvertebrate community structure. However, the hydrological relevance of flow length and travel time are logically superior to straight-line and slope distance and should be researched further. Several individual questions in the PFC assessment had statistically significant relationships with the final reach ratings and with field-measured characteristics. Two of the checklist questions were significantly related to the number of cow droppings. This may indicate a useful and efficient measure of stream degradation due to grazing. The handling and use of the PFC assessment within the BLM needs further documentation and examination for scientific viability, and the addition of quantitative measurements to the PFC in determining restoration potential would be desirable.
Master of Science
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He, Jianhao. "The development of structure-based tidal stream turbine condition monitoring systems." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/111196/.

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The research presented considers the design, development and building of a structure-based condition monitoring system. A series of physical experiments were designed and conducted in a wind tunnel. This was able to initially prove the feasibility of the proposed system. Using a simulation of the continuous turbine rotation the self-initiated Phase-Angle curve was defined. The algorithms so produced were validated and tested using both the simulated waveforms and experimental data sets. This demonstrated that the proposed monitoring system was able to deal with the ever-changing flow conditions and turbine operation status. The work showed that the use of the wind tunnel was feasible for developing the structure-based monitoring system. It has been shown that innovative ideas can be tested and validated in the wind tunnel. The relatively small size of the test rig and the utility of 3-D printing technology made the whole experiment based investigation very cost-effective. The progressive experiments were conducted to compare widely used monitoring techniques to the proposed monitoring system. Some other physical phenomenon or extended thoughts such as blade tip deflection caused by the tower were considered and may be of interest to other researchers. The final discussion of the work presented was to introduce the potential problems and difficulties in applying the proposed system in the marine environment. This considered the sensor design, system installation, application methods and algorithm optimisation. This could further serve the useful information for the relevant researchers and the experiment or deployment of the proposed system on full-size turbine.
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Sellens, Claire, and n/a. "The Reference Condition Approach in Disturbed Landscapes: Accounting for Natural Disturbance and a Reference Condition defined by Good Management Practices for River Protection." University of Canberra. School of Resource, Environmental and Heritage Sciences, 2007. http://erl.canberra.edu.au./public/adt-AUC20081029.131335.

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This study has contributed to the development of the reference condition approach in disturbed landscapes. The reference condition approach has been an important development for the bioassessment of aquatic ecosystems by providing a practical tool for the accurate assessment of river condition. The selection of appropriate reference sites is critical to the success of the predictive model in terms of being able to distinguish between natural variation in biota and the effects of human disturbance. Capturing natural variability and explaining it is a key difference between the reference condition approach and other study designs (e.g. before/after/control/impact). Natural disturbances such as drought or bushfire can significantly alter the ecological condition of streams, and although the ecological condition of streams affected by natural drought or bushfire is part of the natural cycle, this natural variation of the ecological condition is rarely incorporated into many study designs because of a mismatch in time scales. Human disturbance has also significantly altered the condition of landscapes through the development of agriculture and urbanisation. In urban or agricultural landscapes it can be impossible to locate streams that have not been modified by human activity for use as a reference condition. This study looked at the effects of natural disturbance on the reference condition, in terms of the way natural disturbance affects the prediction of stream condition and also the incorporation of the condition of streams experiencing natural disturbance into a predictive model. Additionally this study identified an alternative benchmark for modified landscapes based on the presence of good management practices for river protection, and tested this benchmark for the assessment of streams impacted by urbanisation. Drought and bushfire regularly disturb aquatic ecosystems in Australia, and affected reference sites in the ACT and South Coast region of New South Wales in 2002 and 2003. Drought and bushfire conditions affected macroinvertebrates and environmental variables across these streams, and the majority of sites were assessed as significantly impaired using regional AUSRIVAS (AUstralian RIVers Assessment System) models. This indicated the existing reference conditions for these regions had not incorporated the ecological conditions of reference sites suffering these natural disturbances. Many of the environmental variables used to predict the condition of streams were also affected by drought or bushfire. The changes to environmental variables affected how sites were assessed in models, but the overall assessment was not significantly changed from the initial assessment that drought or bushfire had significantly impaired the ecological condition. To reduce potential assessment errors associated with changes to predictor variables an attempt was made to construct new models with changeable variables excluded. However, it was not possible to completely exclude these types of variables, and subsequent models were no better than the original models in terms of changes to predictor variables affecting the generation of expected taxa lists. The changes to environmental variables did not affect the actual assessment of site condition because although group membership probabilities were changed the probabilities of taxon occurrence did not change significantly. The different reference site groups all contained some common taxa that occurred at most sites and even when group probabilities changed this did not change the probability of these taxa occurring at a test site. For regional models, such as the ACT or NSW South Coast, changes to predictor variables may not significantly affect the assessment of site condition. Incorporating reference sites under drought conditions into a predictive model was an effective way of discriminating the effects of drought from human disturbance. The model only provided two different ecological conditions, a single drought measurement and a single non-drought measurement, so the model did not fully encompass the potential natural variability. The model has value as a starting point and was effective in distinguishing sites affected by human disturbance from sites affected by drought. Good Management Practice (GMP) for river protection is any intervention that minimises human impact on stream condition. Urban sites protected by GMP were used as an alternative benchmark to a minimally impacted reference condition. The criteria used to select reference sites were not sufficiently robust to detect a significant benefit of GMP on physical or chemical characteristics of protected sites, compared to sites without GMP. In general however, the physical and chemical condition of GMP sites was better than sites without GMP and there were significant differences in macroinvertebrate assemblages of GMP and non-GMP sites. A refinement to the site selection process is proposed to include a specific assessment of GMP effectiveness for the protection it is designed to provide. This will substantially improve the robustness of a GMP benchmark and provide a clearer picture of the factors controlling biota in urban streams protected by GMP. The GMP benchmark was developed into a predictive model for the assessment of urban stream health, and in terms of the assessment of test site condition, it did not differ significantly from a model using minimally impacted sites. The purpose of the GMP benchmark was to provide an alternative reference condition for the assessment of stream health in modified landscapes when minimally impacted sites are unavailable or provide an unattainable benchmark. The GMP reference condition as an alternative can provide an attainable and realistic benchmark. The development and application of the suggested site selection protocol will improve the robustness of the GMP benchmark and better account for natural variation in the biota and physical characteristics of the sites used to determine the reference condition.
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Floro, Christopher V. O. "Development of predictive equations based on Pavement Condition Index data." Thesis, Seattle, Washington : University of Washington, 1992. http://handle.dtic.mil/100.2/ADA250625.

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Thesis (M.S. in Civil Engineering)--University of Washington, 1992.
Missing pages A3, A7, A8, A10-A26, A28-A45. "March 1992." Description based on title screen as viewed on April 7, 2009. Includes bibliographical references. Also available in print.
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Zweig, Christa L. "Body condition index analysis for the American alligator (Alligator mississippiensis)." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0000836.

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9

Poirier, Schmitz Alfredo. "Invariant Measures and a Weak Shadowing Condition." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/95172.

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We review the concept of invariant measure and study conditions under which linear combinations of averages along periodic orbits are dense in the space of invariant measures.
Revisamos el concepto de medida invariante y estudiamos condiciones bajo las cuales combinaciones lineales de promedios a lo largo de órbitas periódicas son densas en el espacio de medidas invariantes.
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Allmark, Matthew James. "Condition monitoring and fault diagnosis of tidal stream turbines subjected to rotor imbalance faults." Thesis, Cardiff University, 2016. http://orca.cf.ac.uk/98633/.

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The main focus of the work presented within this thesis was the testing and development of condition monitoring procedures for detection and diagnosis of HATT rotor imbalance faults. The condition monitoring processes were developed via Matlab with the goal of exploiting generator measurements for rotor fault monitoring. Suitable methods of turbine simulation and testing were developed in order to test the proposed CM processes. The algorithms were applied to both simulation based and experimental data sets which related to both steady-state and non-steady-state turbine operation. The work showed that development of condition monitoring practices based on analysis of data sets generated via CFD modelling was feasible. This could serve as a useful process for turbine developers. The work specifically showed that consideration of the torsional spectra observed in CFD datasets was useful in developing a, ‘rotor imbalance criteria’ which was sensitive to rotor imbalance conditions. Furthermore, based on the CFD datasets acquired it was possible to develop a parametric rotor model which was used to develop rotor torque time series under more general flow conditions. To further test condition monitoring processes and to develop the parametric rotor model developed based on CFD data a scale model turbine was developed. All aspects of data capture and test rig control was developed by the researcher. The test rig utilised data capture within the turbine nose cone which was synchronised with the global data capture clock source. Within the nose cone thrust and moment about one of the turbine blades was measured as well as acceleration at the turbine nose cone. The results of the flume testing showed that rotor imbalance criteria was suitable for rotor imbalance faults as applied to 4 generator quadrature axis current measurements as an analogue for drive train torque measurements. It was further found that feature fusion of the rotor imbalance criterion calculated with power coefficient monitoring was successful for imbalance fault diagnosis. The final part of the work presented was to develop drive train simulation processes which could be calculated in real-time and could be utilised to generate representative datasets under non-steady-state conditions. The parametric rotor model was developed, based on the data captured during flume testing, to allow for non-steady state operation. A number of simulations were then undertaken with various rotor faults simulated. The condition monitoring processes were then applied to the data sets generated. Condition monitoring based on operational surfaces was successful and normalised calculation of the surfaces was outlined. The rotor imbalance criterion was found to be less sensitive to the fault cases under non-steady state condition but could well be suitable for imbalance fault detection rather than diagnosis.
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Books on the topic "Index of Stream Condition"

1

Victoria. Department of Sustainability and Environment. Index of stream condition: The second benchmark of Victorian river condition. Melbourne: Dept. of Sustainability and Environment, 2005.

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2

O'Neil, Patrick E. Application of the index of biotic integrity for assessing biological condition of wadeable streams in the Black Warrior River system, Alabama. Tuscaloosa, Ala: Geological Survey of Alabama, Environmental Geology Division, 2000.

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LaPine, Dik. Leadership cartoon index, 1980-1997. [Wisconsin?: D. LaPine?], 1997.

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Canada. Environment Canada. Inland Waters Directorate. Surface water data reference index: Canada. Ottawa: Environment Canada. Inland Waters Directorate, 1991.

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Assessing stream health: Using BLM's proper functioning condition survey method. [Place of publication not identified]: U.S. Department of the Interior, Bureau of Land Management, 1995.

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Hallock, David. A water quality index for Ecology's stream monitoring program. [Olympia, Wash.]: The Department of Ecology, 2002.

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Mitchell, Philip. The environmental condition of Victorian streams: A report. [Melbourne, Vic.]: The Department, 1990.

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Fritz, Ken M. Field operations manual for assessing the hydrologic permanence and ecological condition of headwater streams. Washington, D.C: United States Environmental Protection Agency, Office of Research and Development, 2006.

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Goldstein, Robert M. Development of a stream habitat index for use with an index of biotic integrity in the St. Croix River basin, Minnesota. Mounds View, Minn: U.S. Dept. of the Interior, U.S. Geological Survey, 2000.

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M, Goldstein Robert. Development of a stream habitat index for use with an index of biotic integrity in the St. Croix River basin, Minnesota. Mounds View, Minn: U.S. Dept. of the Interior, U.S. Geological Survey, 2000.

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Book chapters on the topic "Index of Stream Condition"

1

Roth, N., M. Southerland, J. Chaillou, R. Klauda, P. Kazyak, S. Stranko, S. Weisberg, L. Jr Hall, and R. Morgan. "Maryland Biological Stream Survey: Development of a Fish Index of Biotic Integrity." In Monitoring Ecological Condition at Regional Scales, 89–106. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-4976-1_7.

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Nguyen, Chi Cong, Phuoc Vo, Viet Long Doan, Quang Binh Nguyen, Tien Cuong Nguyen, and Quoc Dinh Nguyen. "Assessment of the Effects of Rainfall Frequency on Landslide Susceptibility Mapping Using AHP Method: A Case Study for a Mountainous Region in Central Vietnam." In Progress in Landslide Research and Technology, Volume 1 Issue 2, 2022, 87–98. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-18471-0_7.

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AbstractVietnam’s mountainous regions often encounter landslides, frequently resulting in fatalities, infrastructure damage, and landscape destruction. A landslide susceptibility map is an effective tool for mitigating disaster impacts on hazard-prone areas. This study investigates the applicability of the Analytic Hierarchy Process to produce a landslide susceptibility index. Eight major impact factors are analyzed using SAGA, a GIS-based toolkit, including slopes, aspect, land use, soil type, elevation, distance to road, distance to stream, and antecedent rainfall. Four landslide susceptibility maps are produced corresponding to frequency scenarios of 3-day antecedent rainfall data which is taken from Regional Frequency Analysis (RFA). We assess the modeling performances using Area Under the Curve (AUC) index and the results show that the AHP model has good performance. The findings demonstrate a significant influence of rainfall antecedent conditions on the susceptibility map of landslides in this study area.
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Reiss, Kelly. "Florida Wetland Condition Index." In Encyclopedia of Quality of Life and Well-Being Research, 2301–5. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-007-0753-5_1062.

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Klauda, R., P. Kazyak, S. Stranko, M. Southerland, N. Roth, and J. Chaillou. "Maryland Biological Stream Survey: A State Agency Program to Assess the Impact of Anthropogenic Stresses on Stream Habitat Quality and Biota." In Monitoring Ecological Condition at Regional Scales, 299–316. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-4976-1_23.

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Stevenson, R. Jan. "Diatom Indicators of Stream and Wetland Stressors in a Risk Management Framework." In Monitoring Ecological Condition at Regional Scales, 107–18. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-4976-1_8.

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Hall, Robert K., Peter Husby, Gary Wolinsky, Olof Hansen, and Michiko Mares. "Site Access and Sample Frame Issues for R-EMAP Central Valley, California, Stream Assessment." In Monitoring Ecological Condition at Regional Scales, 357–67. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-4976-1_28.

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Moore, Kristin A., and David A. Murphey. "Index of the Condition of Children." In Encyclopedia of Quality of Life and Well-Being Research, 3183–87. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-007-0753-5_3846.

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Whittier, Thomas R., and Edward T. Rankin. "Regional Patterns in Three Biological Indicators of Stream Condition in Ohio." In Ecological Indicators, 975–95. Boston, MA: Springer US, 1992. http://dx.doi.org/10.1007/978-1-4615-4661-0_12.

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Di Napoli, Claudia, Alessandro Messeri, Martin Novák, João Rio, Joanna Wieczorek, Marco Morabito, Pedro Silva, Alfonso Crisci, and Florian Pappenberger. "The Universal Thermal Climate Index as an Operational Forecasting Tool of Human Biometeorological Conditions in Europe." In Applications of the Universal Thermal Climate Index UTCI in Biometeorology, 193–208. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-76716-7_10.

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AbstractIn operational weather forecasting standard environmental parameters, such as air temperature and humidity, are traditionally used to predict thermal conditions in the future. These parameters, however, are not enough to describe the thermal stress induced by the outdoor environment to the human body as they neglect the human heat budget and personal characteristics (e.g. clothing). The Universal Thermal Climate Index (UTCI) overcomes these limitations by using an advanced thermo-physiological model coupled with a state-of-the-art clothing model. Several systems have been recently developed to operationally forecast human biometeorological conditions via the UTCI, i.e. by computing UTCI from the forecasts of air temperature, humidity, wind speed and radiation as provided by numerical weather prediction models. Here we describe the UTCI-based forecasting systems developed in Czech Republic, Italy, Poland, Portugal and at the pan-European scale. Their characteristics are illustrated and their potential as warning systems for thermal hazards discussed.
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"Effects of Urbanization on Stream Ecosystems." In Effects of Urbanization on Stream Ecosystems, edited by Terry M. Short, Elise M. P. Giddings, Humbert Zappia, and James F. Coles. American Fisheries Society, 2005. http://dx.doi.org/10.47886/9781888569735.ch18.

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<em>Abstract.</em>—Relations between stream habitat and urban land-use intensity were examined in 90 stream reaches located in or near the metropolitan areas of Salt Lake City, Utah (SLC); Birmingham, Alabama (BIR); and Boston, Massachusetts (BOS). Urban intensity was based on a multi-metric index (urban intensity index or UII) that included measures of land cover, socioeconomic organization, and urban infrastructure. Twenty-eight physical variables describing channel morphology, hydraulic properties, and streambed conditions were examined. None of the habitat variables was significantly correlated with urbanization intensity in all three study areas. Urbanization effects on stream habitat were less apparent for streams in SLC and BIR, owing to the strong influence of basin slope (SLC) and drought conditions (BIR) on local flow regimes. Streamflow in the BOS study area was not unduly influenced by similar conditions of climate and physiography, and habitat conditions in these streams were more responsive to urbanization. Urbanization in BOS contributed to higher discharge, channel deepening, and increased loading of fine-grained particles to stream channels. The modifying influence of basin slope and climate on hydrology of streams in SLC and BIR limited our ability to effectively compare habitat responses among different urban settings and identify common responses that might be of interest to restoration or water management programs. Successful application of land-use models such as the UII to compare urbanization effects on stream habitat in different environmental settings must account for inherent differences in natural and anthropogenic factors affecting stream hydrology and geomorphology. The challenge to future management of urban development is to further quantify these differences by building upon existing models, and ultimately develop a broader understanding of urbanization effects on aquatic ecosystems.
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Conference papers on the topic "Index of Stream Condition"

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Kim, J. M., H. C. Song, S. Y. Kang, S. H. Park, J. S. Yang, and Y. H. Kim. "Stress Index Development for Special Elbows." In ASME 2009 Pressure Vessels and Piping Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/pvp2009-77151.

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The reactor coolant piping system is designed to be in compliance with the requirements of Class 1 piping of Section III of the ASME Boiler and Pressure Vessel Code. Stress indices are required to evaluate the nuclear Class 1 piping. The reactor coolant system of Kori 1 nuclear power plant consists of a 2-loop system, each having two special elbows: one is the reducing elbow with a non-uniform thickness, and the other is the elbow with a splitter installed inside the elbow. However, stress indices for special elbows are not specified in NB-3683.7 of the ASME Code. In this paper, we computed the stress indices of special elbows for pressure and moment loads by the finite element analysis. The linear elastic method was used for the analysis with the finite element program, ANSYS, and the solid element (SOLID 45) was selected to model the geometry. The finite element model of the special elbows included a straight segment of pipe on each end of the elbows. The uniformly distributed internal pressure was applied to the pipe and elbow. The equivalent axial blow-off load was applied to one end, and the translational degree of freedom was fixed at the other end of the model. The moment was applied to one end, and the boundary condition was fixed at the other end of the model. Based on the analysis results, it is concluded that stress indices, except B1, in NB-3683.7 of the ASME Code can be used for special elbows conservatively. More analyses are required to apply B1 index to the special elbows.
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Zhang, Hong-wei, Huai-liang Chen, Wei-dong Yu, and Zhong-yang Liu. "The theories of shortwave infrared perpendicular water stress index and its application in soil moisture retrieval under full covered vegetation condition." In Remote Sensing and Modeling of Ecosystems for Sustainability VIII. SPIE, 2011. http://dx.doi.org/10.1117/12.896645.

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Matsuura, Masami, Simon Tupin, and Makoto Ohta. "Compliance Effect on the Flow Condition in Vascular In Vitro Experiments." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-87362.

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Endovascular treatment has become the standard for intracranial aneurysm management. In vitro systems including an artery model are required for devices evaluation and clinician training. Although silicone is usually use for such model, its compliance is known to be lower than blood vessels. The purpose of this study was to analyze the influence of model material compliance on flow properties. Silicone and 12 [wt%] poly (vinyl alcohol) hydrogel (PVA-H) were used to create two box-shaped models of significantly different compliance. The inner lumen geometry was a 4 [mm] diameter straight tube (parent vessel) and a 10 [mm] diameter sphere representing the aneurysm. A blood-mimicking fluid made of a mixture of glycerin, water and sodium iodide was used to reproduce the viscosity and density of blood and fit models refractive index. The circulation system consisted of a pulsatile blood pump and resistance valve. A flow rate of 250±50 [ml/min] and pressure from 75 to 115 [mmHg] were set inside the model. Pressure and flow rate sensors were used to monitor flow conditions before and after the model. Particle image velocimetry (PIV) was performed to record the difference of flow patterns inside the aneurysm of both model using a Nd:YAG solid laser system and fluorescent particles. Results revealed a significant change of flow conditions due to model compliance. Attenuation of the flow rate pulse was recorded between the inlet and the outlet of the both model. This attenuation was 51% for PVA-H model. Moreover, a time lag between outlet pressure and outlet flow rate curves was recorded in both model. This time lag was longer with the PVA-H model, as this model exhibit a greater compliance. PIV experiments revealed significant changes of flow patterns and velocity inside the aneurysm. Because of its high compliance, PVA-H model walls moved under the pulsatile conditions. A change of flow direction and decrease of its velocity were observed near the proximal wall of the aneurysm, compared to the silicone model. Such differences might modify the stress on the wall of the aneurysm. To conclude, our experiments revealed that compliance has significant impacts on flow properties and should be taken into account for in vitro vascular model manufacturing.
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Kanematsu, Wataru, Yukihiko Yamauchi, and Shoji Ito. "Effect of Machining Conditions on the Strength Distributions of Ground Ceramics." In ASME 1997 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/97-gt-320.

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The relationship between strength distribution or ground ceramics and machining condition was examined. The strength of ground silicon carbide ceramics at the failure probability of 1 percent, which is termed 1 % strength, was estimated as a function of the maximum grain depth of cut g, which is used as an index of grinding conditions. It is assumed that the fracture is governed by the competing failure mechanism between pre-existing flaws and machining cracks and that the Weibull modulus of machining cracks was independent of grinding condition. The deviation from estimated value is noticeable in small g region although experimental data of the 1% strength of ground specimen approaches that of polished ones with diminishing g. The observed discrepancy is inferred to be attributed to an increase in stress intensity factor by the interaction between a pre-existing flaw and its adjacent machining crack.
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Krasnoshchekova, V. N., and N. Y. Ilyukhin. "FEATURES OF THE REACTIONS OF THE FUNCTIONAL SYSTEMS OF THE STUDENTS' BODY DURING PERIODS OF HIGH EMOTIONAL STRESS." In The 16th «OCCUPATION and HEALTH» Russian National Congress with International Participation (OHRNC-2021). FSBSI “IRIOH”, 2021. http://dx.doi.org/10.31089/978-5-6042929-2-1-2021-1-285-288.

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Abstract: The study of the features of the reactions of functional shifts of the body systems of students in order to prevent the formation of pathological changes and preserve health at high intensity of the learning process. In the simulated conditions of knowledge control (performance of tests, tasks, practical skills) with the help of the SAN questionnaire, significant fluctuations in activity and mood indicators were revealed (p<0.5), according to the results of the test «Self-assessment of personal stress resistance», 16% of 50 students rated their condition «above average» and changes in hemodynamic indicators-the autonomic Kerdo index and the endurance coefficient indicate a high load on the autonomic nervous system and the inability to perform work productively in the previous mode.
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Shi, Lin, Changyuan Gao, Guoliang Zhang, Guocheng Sun, Xu Wang, Liutao Chen, and Jun Tan. "Study of Iodine-Induced Stress Corrosion Cracking of CZ2 Alloy." In 2022 29th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/icone29-93835.

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Abstract This paper is dealing with the iodine-induced stress corrosion cracking behavior of CZ2 zirconium alloy which is developed by China General Nuclear Power Group. The alloy in this study was fabricated with four different final annealing temperature in the range of 450 °C to 600 °C. In order to investigate the iodine-induced stress corrosion cracking behavior of CZ2 alloy, the slow strain rate tensile tests of four different CZ2 were conducted with three different iodine partial pressure of 0Pa, 10Pa and 10000Pa. The temperature of the tests was 350 °C and the strain rate was 1.4 × 10−6s−1. Also, the sensitivity index of iodine-induced stress corrosion cracking was calculated. The iodine-induced stress corrosion cracking sensitivity index of recrystallized CZ2 alloy is lower than that of stress-relieved CZ2 alloy, and with the increase of final annealing temperature, the sensitivity index decreases gradually. Finally, the fracture surface of CZ2 alloy was observed by scanning electron microscopy. The fracture feature of all four different CZ2 alloy changes from ductile fracture morphology to brittle fracture morphology with the increase of iodine partial pressure. Under the condition of 10000 Pa iodine partial, the fracture feature of stress-relieved CZ2 shows obvious brittle cleavage fracture, the fracture feature of partially recrystallized CZ2 is partly ductile fracture and partly cleavage fracture morphology. For recrystallized CZ2, there are many dimples in the fracture morphology, and shows obvious ductile fracture.
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Karagiozova, Tzviatka, and Plamen Ninov. "HYDROLOGICAL DROUGHT AND FIRE RELATIONSHIP." In XXVII Conference of the Danubian Countries on Hydrological Forecasting and Hydrological Bases of Water Management. Nika-Tsentr, 2020. http://dx.doi.org/10.15407/uhmi.conference.01.13.

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Drought can be defined in meteorological terms or in relative terms with respect to hydrology and ecosystems. Meteorological drought is not a necessary or a sufficient condition for fire, because fires burn during conditions of normal seasonal aridity. Drought occurs without wildfires in the absence of ignitions. However, when drought occurs, both live and dead fuels can dry out and become more flammable. Hydrologic drought as natural event is the result of long-lasting rainfall in the catchment area leading to the gradual depletion of water resources in the river network and the occurrence of a drought. Typically, hydrological drought is recorded as a river runoff below acceptable critical value. The authors explore the relationship between hydrological drought and forest fires. They present projections of fire-related drought indicators: the hydrologic indicator 7Q10 (the lowest 7-day average flow that occurs on average once every 10 years). The implementation of the hydrological drought as an approach for fire risk assessment has just started in Bulgaria. For this purpose, the assessment of the feasibility of using the hydrological 7Q10 drought index as a fire hazard indicator in real time is based on archive information on the variation of hydrological characteristics in the river network before and during an actual fire in an accepted pilot catchment. The Hydrologic Index 7Q10 for the pilot catchment of the Struma River was determined according to the rules for the last 15 years (2003-2017) using the daily water flows from all hydrometric stations The results of the presented study confirm the possibility of using the hydrological 7Q10 drought index to assess the risk of real-time fires by information on runoff from operational hydrological stations. One of the largest fires in the Struma River in 2017 occurred in an area identified as a fire on a highly hazard area according to the hydrological drought index 7Q10.
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Keifer, Kurt A., Mohamed Y. Shahin, and David E. Pendleton. "Pile Condition Index Development." In 11th Triennial International Conference on Ports. Reston, VA: American Society of Civil Engineers, 2007. http://dx.doi.org/10.1061/40834(238)123.

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Karacal, Cem, Sohyung Cho, and William Yu. "Sensor stream mining for tool condition monitoring." In Industrial Engineering (CIE39). IEEE, 2009. http://dx.doi.org/10.1109/iccie.2009.5223555.

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Khan, Naushad Hasin, and M. A. Hassan. "Free Convection in Viscoplastic Fluid due to Partial Bi-Heating From Bottom." In ASME 2016 Heat Transfer Summer Conference collocated with the ASME 2016 Fluids Engineering Division Summer Meeting and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ht2016-1065.

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The numerical investigation of laminar natural convection of viscoplastic fluid in a two dimensional square enclosure has been reported in this work. The enclosed fluid is subjected to partial bi-heating from the bottom wall and symmetrical cooling from the sides under steady condition. Yield stress fluid has been heated through two heaters symmetrically placed on the either side of the centre of the bottom wall of the square enclosure. The viscoplastic fluid is the one which requires a minimum critical stress called yield stress to flow otherwise behave as a solid, have been modeled with Herschel–Bulkley model. Such fluids have significant technological relevance due to its wide application ranging from cosmetics products, food processing industries, pharmaceuticals to natural occurring like flow of debris and lava. The solution of governing partial differential equations has been approached using finite volume based formulation. Non uniform set of grid has been used. The effects of yield stress, heat flux, and power law index on the flow and thermal characteristics of the free convection of Herschel-Bulkley fluids have been studied for a particular value of Prandtl number. The flow and thermal fields have been investigated for the following ranges of conditions: Rayleigh number varies between 103 and 106 whereas power law index ranges from 0 to 1. The heat transfer characteristic has been depicted with the help of isotherms and the flow field has been illustrated by streamlines. The onset of convection is substantially delayed due to presence of yield stress of the fluid. This results in enhanced critical Rayleigh number for onset of convection. With increase in the Yield number in turn yield stress, results in the weakening of heat transfer through convection and at a particular relatively higher value of Yield number the heat transfer is solely taken place by conduction mode. Due to the symmetry in both heating and boundary conditions, the obtained isotherms and streamlines of the right half are symmetrical to the left half of the square enclosure. The conductive mode of heat transfer becomes dominated by increasing yield stress and reducing Ra and vice versa. The simultaneous presence of yielded and unyielded region presents an interesting pattern in the convection zone. Furthermore, it can be seen that rise in heat flux, in turn Ra, promotes the buoyancy driven circulation of viscoplastic fluid i.e. enhances natural convective heat transfer. In addition, the effect of power law index has been investigated. Power law index has little effect on thermal distribution and flow field.
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Reports on the topic "Index of Stream Condition"

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Pruitt, Bruce, and S. Kyle McKay. A reference condition index for urban streams. Environmental Laboratory (U.S.), August 2017. http://dx.doi.org/10.21079/11681/22821.

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Rosse, Anine. Stream channel monitoring for Wind Cave National Park 2021 Data report. National Park Service, January 2023. http://dx.doi.org/10.36967/2296623.

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The Northern Great Plains Inventory and Monitoring Network (NGPN) began stream channel monitoring in Highland Creek at Wind Cave National Park (WICA) in 2021. This data report summarizes the data collected during the 2021 season pertaining to watershed, reach, and physical habitat. After data are collected for at least four cycles, trends may be reported. This report covers three main areas: 1) Reporting on upland channel characteristics data that may affect habitat such as: land cover, drainage area, and total stream length; 2) Reporting of geomorphic dimensions such as: channel widths, bank angles, vegetative cover, reach slope, measures of bank stability; and 3) Determining physical habitat characteristics such as: size and distribution of bed sediment, large woody debris, and canopy cover. Indices, benchmarks, and other studies are provided in the table for informational purposes to help put Highland Creek’s measurements in context but should not be considered as a reference condition. Upland characteristics of the watershed indicate high natural land use cover (forest, grassland, and shrubland) with little development in the area. Reach characteristics include bank cover, heights, bank stability index, and vegetative cover. In addition to animal-induced erosion of the banks, bank sloughing and widening are occurring. Angles are steep, and there are some sandy banks that are unstable. When plots are revisited in three years, there will be greater understanding of the processes at play and the condition of the stream. Physical characteristics include median particle size, percentage fine substrate, geomorphic units, and canopy cover. Gravel substrate still covers much of the stream; there are wide meanders in the stream bed; and a variety of geomorphic channel units (pool, riffle, run) occur in the creek all of which are indicators of healthy habitat. While there is an absence of large woody debris and canopy cover is low, many grassland streams in good condition can have similar characteristics. More data are needed to fully assess those components and determine a suitable reference condition that can be used to later assess the status and trends of Highland Creek. The reach data contained in this report are specific to a short 150-m segment of Highland Creek and cannot be extrapolated to conditions elsewhere in the creek or to the park in general. Bank erosion and bank instability were observed along the majority of transects at site WICA SCM 001.
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Pruitt, Bruce, K. Killgore, William Slack, and Ramune Matuliauskaite. Formulation of a multi-scale watershed ecological model using a statistical approach. Engineer Research and Development Center (U.S.), November 2020. http://dx.doi.org/10.21079/11681/38862.

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The purpose of this special report is to provide a statistical stepwise process for formulation of ecological models for application at multiple scales using a stream condition index (SCI). Given the global variability of aquatic ecosystems, this guidance is for broad application and may require modification to suit specific watersheds or stream reaches. However, the general statistical treatise provided herein applies across physiographies and at multiple scales. The Duck River Watershed Assessment in Tennessee was used, in part, to develop and test this multiscale, statistical approach; thus, it is considered a case example and referenced throughout this report. The findings of this study can be utilized to (1) prioritize water-sheds for restoration, enhancement, and conservation; (2) plan and conduct site-specific, intensive ecosystem studies; and (3) assess ecosystem outcomes (that is, ecological lift) applicable to future with and without restoration actions including alternative, feasibility, and cost-benefit analyses and adaptive management.
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4

Sherman, Wesley, and Gerry Pang. Small Patient Condition Stream Generator (SPCSG): Version 2.0. Fort Belvoir, VA: Defense Technical Information Center, December 2010. http://dx.doi.org/10.21236/ada562858.

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Moran, Daniel S., Kent B. Pandolf, and Richard R. Gonzalez. Evaluation and Refinement of the Environmental Stress Index (ESI) for Different Climatic Conditions and Distances Below and Above Sea Level. Fort Belvoir, VA: Defense Technical Information Center, November 2001. http://dx.doi.org/10.21236/ada396492.

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Rodrigues Bastos, Fabiano, Diego Gutiérrez, and Virginia Queijo Von Heideken. No Time for Later: Rebuilding Macro Buffers in the Southern Cone amid a Revamped Global Financial Landscape. Inter-American Development Bank, December 2022. http://dx.doi.org/10.18235/0004571.

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Global financial shocks under a revamped global financial landscape can produce unexpected, multi-faceted, and disruptive implications for emerging market economies. Using the VIX index as a proxy for global financial stress, we argue that Southern Cone macro conditions can undergo significant pressure under adverse global financial shocks. The region needs to start rebuilding macro buffers now -in addition to simultaneously correcting macro imbalances and enhancing policy frameworks- to cope with the emerging global financial environment. International organizations, including multilateral development banks, can play several key roles in supporting the rebuilding of macro buffers.
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Bonfil, David J., Daniel S. Long, and Yafit Cohen. Remote Sensing of Crop Physiological Parameters for Improved Nitrogen Management in Semi-Arid Wheat Production Systems. United States Department of Agriculture, January 2008. http://dx.doi.org/10.32747/2008.7696531.bard.

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To reduce financial risk and N losses to the environment, fertilization methods are needed that improve NUE and increase the quality of wheat. In the literature, ample attention is given to grid-based and zone-based soil testing to determine the soil N available early in the growing season. Plus, information is available on in-season N topdressing applications as a means of improving GPC. However, the vast majority of research has focused on wheat that is grown under N limiting conditions in sub-humid regions and irrigated fields. Less attention has been given to wheat in dryland that is water limited. The objectives of this study were to: (1) determine accuracy in determining GPC of HRSW in Israel and SWWW in Oregon using on-combine optical sensors under field conditions; (2) develop a quantitative relationship between image spectral reflectance and effective crop physiological parameters; (3) develop an operational precision N management procedure that combines variable-rate N recommendations at planting as derived from maps of grain yield, GPC, and test weight; and at mid-season as derived from quantitative relationships, remote sensing, and the DSS; and (4) address the economic and technology-transfer aspects of producers’ needs. Results from the research suggest that optical sensing and the DSS can be used for estimating the N status of dryland wheat and deciding whether additional N is needed to improve GPC. Significant findings include: 1. In-line NIR reflectance spectroscopy can be used to rapidly and accurately (SEP <5.0 mg g⁻¹) measure GPC of a grain stream conveyed by an auger. 2. On-combine NIR spectroscopy can be used to accurately estimate (R² < 0.88) grain test weight across fields. 3. Precision N management based on N removal increases GPC, grain yield, and profitability in rainfed wheat. 4. Hyperspectral SI and partial least squares (PLS) models have excellent potential for estimation of biomass, and water and N contents of wheat. 5. A novel heading index can be used to monitor spike emergence of wheat with classification accuracy between 53 and 83%. 6. Index MCARI/MTVI2 promises to improve remote sensing of wheat N status where water- not soil N fertility, is the main driver of plant growth. Important features include: (a) computable from commercial aerospace imagery that include the red edge waveband, (b) sensitive to Chl and resistant to variation in crop biomass, and (c) accommodates variation in soil reflectance. Findings #1 and #2 above enable growers to further implement an efficient, low cost PNM approach using commercially available on-combine optical sensors. Finding #3 suggests that profit opportunities may exist from PNM based on information from on-combine sensing and aerospace remote sensing. Finding #4, with its emphasis on data retrieval and accuracy, enhances the potential usefulness of a DSS as a tool for field crop management. Finding #5 enables land managers to use a DSS to ascertain at mid-season whether a wheat crop should be harvested for grain or forage. Finding #6a expands potential commercial opportunities of MS imagery and thus has special importance to a majority of aerospace imaging firms specializing in the acquisition and utilization of these data. Finding #6b on index MCARI/MVTI2 has great potential to expand use of ground-based sensing and in-season N management to millions of hectares of land in semiarid environments where water- not N, is the main determinant of grain yield. Finding #6c demonstrates that MCARI/MTVI2 may alleviate the requirement of multiple N-rich reference strips to account for soil differences within farm fields. This simplicity will be less demanding of grower resources, promising substantially greater acceptance of sensing technologies for in-season N management.
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8

Hudgens, Bian, Jene Michaud, Megan Ross, Pamela Scheffler, Anne Brasher, Megan Donahue, Alan Friedlander, et al. Natural resource condition assessment: Puʻuhonua o Hōnaunau National Historical Park. National Park Service, September 2022. http://dx.doi.org/10.36967/2293943.

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Natural Resource Condition Assessments (NRCAs) evaluate current conditions of natural resources and resource indicators in national park units (parks). NRCAs are meant to complement—not replace—traditional issue- and threat-based resource assessments. NRCAs employ a multi-disciplinary, hierarchical framework within which reference conditions for natural resource indicators are developed for comparison against current conditions. NRCAs do not set management targets for study indicators, and reference conditions are not necessarily ideal or target conditions. The goal of a NRCA is to deliver science-based information that will assist park managers in their efforts to describe and quantify a park’s desired resource conditions and management targets, and inform management practices related to natural resource stewardship. The resources and indicators emphasized in a given NRCA depend on the park’s resource setting, status of resource stewardship planning and science in identifying high-priority indicators, and availability of data and expertise to assess current conditions for a variety of potential study resources and indicators. Puʻuhonua o Hōnaunau National Historical Park (hereafter Puʻuhonua o Hōnaunau NHP) encompasses 1.7 km2 (0.7 mi2) at the base of the Mauna Loa Volcano on the Kona coast of the island of Hawaiʻi. The Kona coast of Hawaiʻi Island is characterized by calm winds that increase in the late morning to evening hours, especially in the summer when there is also a high frequency of late afternoon or early evening showers. The climate is mild, with mean high temperature of 26.2° C (79.2° F) and a mean low temperature of 16.6° C (61.9° F) and receiving on average 66 cm (26 in) of rainfall per year. The Kona coast is the only region in Hawaiʻi where more precipitation falls in the summer than in the winter. There is limited surface water runoff or stream development at Puʻuhonua o Hōnaunau NHP due to the relatively recent lava flows (less than 1,500 years old) overlaying much of the park. Kiʻilae Stream is the only watercourse within the park. Kiʻilae Stream is ephemeral, with occasional flows and a poorly characterized channel within the park. A stream gauge was located uphill from the park, but no measurements have been taken since 1982. Floods in Kiʻilae Stream do occur, resulting in transport of fluvial sediment to the ocean, but there are no data documenting this phenomenon. There are a small number of naturally occurring anchialine pools occupying cracks and small depressions in the lava flows, including the Royal Fishponds; an anchialine pool modified for the purpose of holding fish. Although the park’s legal boundaries end at the high tide mark, the sense of place, story, and visitor experience would be completely different without the marine waters adjacent to the park. Six resource elements were chosen for evaluation: air and night sky, water-related processes, terrestrial vegetation, vertebrates, anchialine pools, and marine resources. Resource conditions were determined through reviewing existing literature, meta-analysis, and where appropriate, analysis of unpublished short- and long-term datasets. However, in a number of cases, data were unavailable or insufficient to either establish a quantitative reference condition or conduct a formal statistical comparison of the status of a resource within the park to a quantitative reference condition. In those cases, data gaps are noted, and comparisons were made based on qualitative descriptions. Overall, the condition of natural resources within Puʻuhonua o Hōnaunau NHP reflects the surrounding landscape. The coastal lands immediately surrounding Puʻuhonua o Hōnaunau NHP are zoned for conservation, while adjacent lands away from the coast are agricultural. The condition of most natural resources at Puʻuhonua o Hōnaunau NHP reflect the overall condition of ecological communities on the west Hawai‘i coast. Although little of the park’s vegetation...
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9

Shahin, Mohamed Y., Chad Stock, Lisa Beckberger, Chao-Ming Wang, and M. R. Crrovetti. Effect of Sample Unit Size and Number of Survey Distress Types on the Pavement Condition Index (PCI) for Asphalt-Surfaced Roads. Fort Belvoir, VA: Defense Technical Information Center, April 1996. http://dx.doi.org/10.21236/ada310687.

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10

David, Gabrielle, D. Somerville, Julia McCarthy, Spencer MacNeil, Faith Fitzpatrick, Ryan Evans, and David Wilson. Technical guide for the development, evaluation, and modification of stream assessment methods for the Corps Regulatory Program. Engineer Research and Development Center (U.S.), October 2021. http://dx.doi.org/10.21079/11681/42182.

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The U.S. Army Corps Regulatory Program considers the loss (impacts) and gain (compensatory mitigation) of aquatic resource functions as part of Clean Water Act Section 404 permitting and compensatory mitigation decisions. To better inform this regulatory decision-making, the Regulatory Program needs transparent and objective approaches to assess the function and condition of aquatic resources, including streams. Therefore, the Regulatory Program needs function-based stream assessments (1) to characterize a stream’s condition or function, (2) to improve understanding of the impact of a proposed action on an aquatic resource, and/or (3) to inform the development of stream compensatory mitigation tools rooted in stream condition and/or function. A function-based stream assessment can provide regulatory decision makers with the resources to objectively consider alternatives, minimize impacts, assess unavoidable impacts, determine mitigation requirements, and monitor the success of mitigation projects. A multiagency National Committee on Stream Assessment (NCSA) convened to create these guidelines to inform the development of new methods and evaluation of both national-level and regional methods currently in use. The resulting guidelines present nine phases, including rationale and recommendations to facilitate work efforts. The NCSA hopes that this technical guide promotes transparency, technical defensibility, and consistent application of stream assessments in the Regulatory Program.
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