888 resultados para Edisto River Wildlife Management Area--Maps
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In July-August 1979 a first survey of Sofala Bank was carried out with shallow water prawn resources as the main objective. Some preliminary conclusions on the circulation in the Sofala Bank and the influence of the Zambezi River in this area were drawn. Analysis of catch rates and distribution of the different prawn species resulted in the division of Sofala Bank in 6 areas. Particular importance is given to the species Penaeus indicus and Metapenaeus monoceros which constitute 70-90% of catches in depths less than 25 m. The greatest concentrations of P. indicus are found very close to the shore, principally in an area north of Quelimane and another south of Angoche. At the time of the survey 40% of females of this species were in late maturing stages. The species M. monoceros is most abundant in depths greater than 15 m, with concentrations south of Zambezi River and in small areas near Pebane and Angoche.
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Poyang Lake (Poyang Hu) is located at the junction of the middle and lower reaches of the Yangtze (Changjiang) River, covering an area of 3283 km(2). As one of the few lakes that are still freely connected with the river, it plays an important role in the maintenance of the unique biota of the Yangtze floodplain ecosystem. To promote the conservation of Poyang Lake, an investigation of the macrobenthos in the lake itself and adjoining Yangtze mainstream was conducted in 1997-1999. Altogether 58 benthic taxa, including, 22 annelids, 8 mollusks, 26 arthropods, and 2 miscellaneous animals, were identified from quantitative samples. The benthic fauna shows a high diversity and a marine affinity. The standing crops of benthos in the lake were much higher than those in the river, being 659 individuals/m(2) and 187.3g/m(2) (wet mass) in the main lake, and 549 individuals/m(2) and 116.6 g/m(2) in the lake outlet, but only 129 individuals/m(2) and 0.4g/m(2) in the river. The dominant roup in the lake was Mollusca, comprising 63.4% of the total in density and 99.5% in biomass. An analysis of the functional feeding structure indicated that collector-filterers and scrapers were predominant in the lake, up to 42.2% and 24.7% in density and 70.2% and 29.2% in biomass, respectively, while shredders and collector-gatherers were relatively common in the river. The present study was restricted to the northern outlet and the northeast part of Poyang Lake. A scrutiny is required for the remaining areas.
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横断山区干旱河谷地区的土壤是制约植被恢复的一个关键要素,但干旱条件下土壤质量与动态演变状况并不清楚,本研究以岷江干旱河谷核心地段的土壤为对象,研究了阳坡褐土土壤的物理、化学以及生物学特征在海拔梯度(1800m、2000m、2200m)格局及其时间动态(2005-2007)变化,应用主成分分析综合评价了土壤质量及其时空差异性,明确了土壤质量的变化趋势。主要研究结论如下: 1) 海拔梯度上土壤物理性状的变化,2005 年和2007 年土壤物理性状综合质量随着海拔的升高均得到了优化,即海拔2200 m>海拔2000 m>海拔1800 m。 2) 海拔梯度上土壤化学性质的变化,土壤化学综合性质2005 年随海拔升高而趋于变得更优,而2007 年海拔2000 m 最优,海拔1800 m 则最差。 3) 海拔梯度上土壤生物学性质的变化,2005 年土壤生物学性质随海拔升高表现出趋于更好,2007 年海拔2000 m 最优而海拔1800 m 地段最差。 4) 从土壤物理、化学、生物学三方面出发,应用主成分分析,分别分析得出2005 年和2007 年不同海拔高度的土壤质量综合得分。根据综合得分得出土壤质量综合评价的排列顺序为:2005 海拔2200 m>2007 年海拔2000 m>2005 年海拔2000 m>2007 年海拔1800 m>2007 海拔2200 m>2005 年海拔1800 m。2005年土壤综合质量随海拔升高而趋好,2007 年则以海拔2000 m 最优,海拔1800 m和2200 m 差异不大。 5)排除人为干扰后,干旱河谷土壤物理性状在海拔1800 m 略有恢复,海拔2000 m 变化不明显,而海拔2200 m 仍有退化趋势;土壤化学性质在海拔1800 m和2000 m 地段得到恢复,而海拔2200 m 处仍有退化;土壤生物学性质在海拔2000 m 地段呈恢复趋势,而1800 m 和2200 m 仍处于退化状态。综合质量分析表明,与2005 年相比,2007 年海拔1800 m 和2000 m 地段土壤质量趋于变优而海拔2200 m 地段仍有退化迹象。 Soil is a key factor that affect the restoration of vegetation in the Hengduan Mountains dry valley area. But the dynamics and quality of soil is not knowed in dry area. In this study, soil physiochemical and biological characteristics ranging from 1800~2200m above sea level from a typical south-facing slope at the Minjiang River dry valley area had been studied, and characteristics of changes in soil quality along altitudinal gradients and time scales were also discussed. The principal component analysis was used to assess the soil quality. The main results were as follows: 1) Changes in soil physical properties along altitudes. Soil physical properties obtained the optimization along with the elevation in 2005 and 2007. 2) Changes in soil chemical properties. It was summarized that soil chemical properties increased with elevation in 2005, but the soil of 2000 m was the best in 2007. 3) Changes in soil biological characteristics. Soil biological properties increased with elevation in 2005, but the soil of 2000 m was the best and 1800 m was the worst in 2007. 4) Change tendency of soil quality. With the soil physics, chemistry and biology characteristics, we analysised the change tendency of soil quality in altitudes. The result indicated that soil quality increased with altituded in 2005, and soil quality of 2000 m was the best in 2007. 5) In brief, the soil quality is by physics, chemistry as well as the biology synthesizes the influence the final outcome. And the soil quality's change was manifested by soil physics, chemistry and the biology characteristics. All the results indicated soil quality still degenerated at 2200 m in in the dry valley of Minjiang River. And soil quality of 1800 m and 2000 m resumed slight.
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抗生素是广泛应用于人类和动物疾病治疗的药物,近年来在养殖业中抗生素更是常常作为动物催长剂。这些抗生素会通过人畜排泄物、药品的丢弃、污水排放、农业废物堆积等途径进入到环境中。环境中抗生素的残留会导致细菌耐药性的产生、微生态平衡的破坏,以及对生态环境和人类难以预知的影响。抗生素污染是近十年来才在国际上引起注意的新型环境问题,目前研究非常薄弱,要深入认识抗生素的环境影响特征就迫切需要对抗生素在环境中的迁移、归宿等地球化学行为进行针对性的研究。本文研究了贵阳城市污水、南明河及乌江渡水库中氯霉素(CAP)、土霉素(OTC)、四环素(TC)和金霉素(CTC)的环境地球化学特征,包括抗生素的分布、迁移特征及影响因素,并分析了贵阳市动物源性食品中抗生素的残留特征,探讨了环境因素对抗生素稳定性及吸附/解吸的影响,以期了解抗生素在环境中的降解、迁移等环境行为的特征,并据此评价抗生素的环境影响特点,为认识抗生素的污染特点、发展相应的控制、治理措施提供科学依据。主要内容包括: 1. 对环境样品中CAP和TCs的前处理过程和检测方法进行了优化。对水样的前处理采用固相萃取的方法,对土壤和沉积物的前处理采用EDTA-McIlvaine振荡萃取、SAX-HLB净化富集的方法;选择HPLC-UV作为分析的手段,对样品中的4种抗生素进行了检测,各化合物得到了很好的分离,该方法简便、快捷、重现性好。 2. 证实了抗生素在城市污水中的普遍存在。贵阳城市污水中以CAP的污染最为突出,其含量明显高于广州地区的城市污水;污水中四环素类药物(TCs)的含量和大多数欧美国家及地区城市污水中TCs的含量相当。这一结果证明,污水中抗生素的污染非常严重,对地表水环境形成严重的威胁。污水中抗生素的来源包括:人服用抗生素药物以及食用含有抗生素残留的食品之后的排泄物;食品中残留的抗生素随剩余食品的丢弃而进入污水。污水中抗生素的含量都具有明显的季节变化规律,冬春季含量明显高于夏秋季,我们认为这与各季节用水量和疾病特点有关。污水中抗生素的大量存在说明:1)抗生素存在滥用的现象,特别是CAP可能存在严重的违法使用,这一现象应当重视;2)污水中的抗生素会威胁水环境质量,应加强处理和控制技术。 3. 证明了城市河流受到多种来源的抗生素影响,其中城市污水是最重要的源,而且抗生素在河流中呈现一定的持久性。南明河上游河段中抗生素的来源包括郊区城镇污水、养鱼场、制药厂污水排放及地表垃圾。城市污水是抗生素的一大排放源,受其影响,排污口下游的河段受到的抗生素污染尤为严重,此外还有来自下游郊区城镇和农业污水的影响。对南明河中抗生素的来源及行为特点的剖析表明:1)抗生素在南明河的水和沉积物中具有不同的分布特征:河水中以CAP的污染最为严重,各水样中CAP的含量基本都高于TCs;而大部分沉积物中TCs的含量都高于CAP。CAP和TCs在水-沉积物之间的分布特征表明,它们在水环境中的地球化学行为明显受到吸附/解吸特点的影响,CAP的亲水性强,而TCs的亲粒性强。2)虽然在养殖业中已禁止使用CAP,但河水和污水中CAP的大量存在,这一结果揭露了CAP仍然存在大量违法使用的事实。3)河水中抗生素含量的季节差异明显,冬春季抗生素的含量高于夏秋季,其原因主要是夏秋季河水流量大,对河水中抗生素的稀释作用强。沉积物中抗生素的含量没有明显的季节变化规律,各季节抗生素的平均含量差异较小。4)受污水影响,各季节排污口下游的南明河水受到的抗生素污染尤为严重,污水口上下游之间的含量差异明显。沉积物在冬季受城市污水的影响大,在排污口下游的抗生素的含量明显高于上游,而春、夏、秋季受污水影响不明显。这可能是因为在春、夏和秋季其它污染源的影响较大,因此污水的影响强度减弱。夏季上游沉积物中CAP的含量甚至高于下游,原因一方面是因为夏季城市污水中抗生素含量低,对南明河的影响减小,另一方面可能因为夏季雨水多、水量大,将上游的地表垃圾以及积累在小河沟中的垃圾冲刷到南明河中,而这些工业及生活垃圾通常是抗生素的一大来源。 抗生素在河流中呈现了一定的持久性,在20 km的范围内水和沉积物显示了明显的污染水平,可能会对水生生态以及流域的环境造成一定的影响。此外,贵阳市南明河两岸的农田通常是用河水进行灌溉的,从而可能使抗生素的污染危及到食物链,对人体的健康有潜在的威胁。 4. 由于食品(如鱼肉、猪肉等)中残留的抗生素是污水中抗生素的重要来源,因此我们研究了养殖业(水产养殖区)中抗生素的环境行为特点,还研究了常见动物源性食品中抗生素的残留特点。对养鱼区的研究表明,养鱼饲料中含有大量的抗生素,是养鱼区水环境中抗生素的来源。由于饲料的颗粒大,且河水流速快,因此饲料中的抗生素不会对水体造成很大的影响,但是在网箱区的沉积物中形成了高含量的残留,除此以外,在乌江渡主航道的河心沉积物中抗生素的含量也相当可观。这说明该区水产养殖的抗生素主要影响沉积物,且相应的污染不是局部的,而会影响到整个养鱼区。从沉积物中抗生素平均含量的季节差异来看,各季TCs的用药量可能不同,秋季的用量可能最大,而其它季节用量相当;CAP在每个季节的用量可能相当。尽管分析的饲料中CAP的含量高于TCs,但在各季节乌江渡水库主航道沉积物中TCs的含量几乎都远高于CAP,这是由于TCs比CAP更易存在于沉积物中。乌江渡水库上下游主航道沉积物中抗生素的含量差异日益减小,说明了乌江渡水库的污染已日益严重。这些抗生素虽然暂时被固定在了沉积物中,活性相对较小,但是在外界条件的影响下,它们的吸附/解吸作用是可以改变的。因此,乌江渡沉积物中高含量的抗生素残留对水生生态环境具有潜在的威胁。 对贵阳市动物源性食品(鱼肉、猪肉和牛奶)中抗生素的残留特征的分析表明,这些食品中普遍残留有高含量的抗生素,被人食用后,其中的抗生素也会被人体摄入,一部分抗生素会随着人的排泄物而进入到污水中,并最终进入环境中;另一部分抗生素会积蓄在人体中,到一定浓度后就会对人体造成伤害。鲩鱼、鲫鱼、鲤鱼、鳙鱼和鲢鱼中CAP、OTC、TC和CTC的平均含量范围分别在57.1~365.5 µg/kg、37.0~60.7µg/kg、34.3~72.4 µg/kg和22.3~68.0 µg/kg之间。秋季的长吻鲍、团头鲂、鲈鱼、长江洄鱼、对虾、黄鳝、泥鳅和猪肉中CAP、OTC、TC和CTC的平均含量分别为88.1 µg/kg、76.8 µg/kg、343.7 µg/kg和34.2 µg/kg;牛奶中的含量分别为4.2 µg/L、1.6 µg/L和2.5 µg/L和22.0 µg/L。 5. 确定了抗生素的稳定性、吸附/解吸作用与各因素的关系,据此可以探讨环境中抗生素的行为特点及机理,并为环境中抗生素的污染防治提供依据。在短时的加热中,TCs发生了部分降解,而CAP却几乎没有发生分解,说明烹饪过程中的加热不能去除食品中的抗生素,这些抗生素则会进入到人体和污水中。当pH在2~8之间时,TCs的性质较稳定;CAP在pH=1~10的范围内性质都比较稳定。地表和地下水体的pH一般为7左右,说明了水环境中TCs受pH的影响小,而CAP几乎不受影响。在6个月的时间内,TCs在3种介质中都发生了不同程度的降解,但仍有大部分残留;CAP几乎没有发生明显的降解,这说明CAP和TCs的污染具有一定的持久性。TCs的吸附/解吸受颗粒物粒径的影响大,粒径越小,吸附越强;CAP不受影响。这证明了在环境中CAP更易以水溶态的形式存在,而TCs更易吸附在沉积物中。颗粒物中CaCO3含量越高,TC和CTC的吸附越强,证明CaCO3可以用来增强TC、CTC的吸附,这为环境中抗生素的治理提供了一条思路。
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En los últimos años han aparecido nuevas formas de turismo más sostenibles, donde existen elementos relacionados con el descanso, el disfrute y la protección del medio ambiente o el conocimiento de la cultura local, a través de políticas que favorecen la sostenibilidad del destino. En este sentido, el ecoturismo se configura como una tipología turística que se desarrolla en contacto con la naturaleza. Este turismo ayuda a mejorar el desarrollo socioeconómico de las comunidades locales, a la vez, que fomenta la conservación de los recursos naturales y el respeto hacia el medio ambiente. Aunque, esta tipología de turismo también genera importantes impactos negativos. El objetivo principal de esta investigación es analizar los impactos socioeconómicos, culturales y medioambientales percibidos por el ecoturismo por parte de los residentes de comunidades rurales de República Dominicana. La técnica de recolección de datos utilizada ha consistido en un cuestionario. Entre las principales conclusiones, cabe destacar que actualmente no se perciben impactos negativos, pero si hay una serie de elementos que hay que ir considerando, con la finalidad de que no se conviertan en un impacto a corto plazo para la comunidad rural.
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The Water Framework Directive (WFD) has initiated a shift towards a targeted approach to implementation through its focus on river basin districts as management units and the natural ecological characteristics of waterbodies. Due to its role in eutrophication, phosphorus (P) has received considerable attention, resulting in a significant body of research, which now forms the evidence base for the programme of measures (POMs) adopted in WFD River Basin Management Plans (RBMP). Targeting POMs at critical sources areas (CSAs) of P could significantly improve environmental efficiency and cost effectiveness of proposed mitigation strategies. This paper summarises the progress made towards targeting mitigation measures at CSAs in Irish catchments. A review of current research highlights that knowledge related to P export at field scale is relatively comprehensive however; the availability of site-specific data and tools limits widespread identification of CSA at this scale. Increasing complexity of hydrological processes at larger scales limits accurate identification of CSA at catchment scale. Implementation of a tiered approach, using catchment scale tools in conjunction with field-by-field surveys could decrease uncertainty and provide a more practical and cost effective method of delineating CSA in a range of catchments. Despite scientific and practical uncertainties, development of a tiered CSA-based approach to assist in the development of supplementary measures would provide a means of developing catchment-specific and cost-effective programmes of measures for diffuse P. The paper presents a conceptual framework for such an approach, which would have particular relevance for the development of supplementary measures in High Status Waterbodies (HSW). The cost and resources necessary for implementation are justified based on HSWs’ value as undisturbed reference condition ecosystems.
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Understanding the spatial distribution of organisms is a central topic in ecology. The European roe deer (Capreolus capreolus) population is in Portugal and Norway at the southwestern and northern edge of its distribution, respectively. Understanding the factors that act on these populations enlightens both local aspects concerning their conservation and wider scale aspects of the species bioclimatic envelope, which is crucial for being better able to predict the impacts of environmental change. The main aim of this thesis was to evaluate roe deer distribution in Portugal and Norway, two countries with contrasting landscapes, seasonality and with different anthropogenic pressure. The interspecific relationship with sympatric ungulates was also analysed. By using pellet group counts, we investigated habitat use of roe deer, identifying the major environmental descriptors, to understand the importance of forest structure, vegetation characteristics, landscape structure and human disturbance on their distribution. The analyses were based on presence – absence data and were carried out at two spatial scales. The results showed that habitat use of roe deer was different across countries. In Portugal, at the local scale, roe deer distribution was positively associated with high density of shrubs, especially heather and brambles, while the presence of red deer had a negative effect on their distribution. At a broad scale, roe deer was negatively associated with spatial heterogeneity, namely mean shape index and made less use of areas close to agricultural fields. In Norway, at the local scale, roe deer made more use of areas with high cover of deciduous trees and patches containing juniper and Vaccinium sp.. At a broad scale, roe deer use patches near edges between fields and forest. In both countries, roe deer make use of areas further away from roads. While in Norway roe deer in both summer and winter are always close to houses, in Portugal they are either far (summer) or indifferent (winter). Anthropogenic disturbance is better tolerated in Norway, where the importance of the critical season seems to be higher. Human disturbance may contribute to roe deer habitat loss in Portugal, while roe deer are able to persist close to humans in managed landscapes in Norway. In fact, some of the differences observed could be more due to the indirect impacts of human exploitation (e.g. presence of free-ranging dogs and hunting regulation) rather than the actual human presence or land-use per se. I conclude that the methodology and tools developed here are readily expandable to address similar questions in different contexts. Wildlife management would benefit greatly from a more holistic/integrative approach and that should include human aspects, as human disturbance is expected to continue increasing.
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Thesis (Master's)--University of Washington, 2013
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El presente trabajo, intenta contribuir a aclarar el potencial que representa un sistema de gestión por competencias para las organizaciones que se dedican a la vigilancia y seguridad privada en lo que se refiere al personal que impacta directamente al cliente desde la gerencia de riesgos, para una eventual implantación y posterior aplicación en las políticas talento humano desde una perspectiva estratégica. Con este objetivo, se abordan, en primer lugar, diversos aspectos útiles a conocer para una cabal comprensión de cómo se caracteriza el sector de la seguridad privada, un conocimiento de la Organización en donde se desarrolló este estudio de caso y el enfoque de competencias y su terminología, en todas sus dimensiones. Esto significa, a grandes rasgos, una aproximación a la metodología para mantener candidatos aptos que desempeñen estos cargos de las organizaciones dedicadas a la gestión de riesgos. Después, se tratarán las competencias desde la perspectiva organizacional, esto es, desde su gestión; abordando distintos aspectos generales útiles a saber previo a una decisión de implantación de la metodología descrita. Luego, se ofrece una visión generalizada acerca de los procesos de implantación, culminando, con la metodología propuesta para un sistema de gestión por competencias siguiendo un enfoque conductista.
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The present paper presents the results of a transversal descriptive study which intended to estimate the contribution of the project “Caring for those who take care of people with disabilities” in the areas of: strength of personal and group competences, self care, life project, dexterity in the care process of people with disabilities, and communitarian auto management; that was implemented in 20 urban areas with caregivers of the city of Bogota in the year 2007. The study allowed the nresearches to acknowledge the little change perception that caregivers had in terms of self care, however, the caregivers perceived change in the four areas, although this were not statistically significant in comparison with the general population. There were only significant changes in the communitarian auto management area in 30% of the population. As a result, it is proposed that more extensive, continuous, and sustainable processes are implemented and that this process arises from contention spaces which can be created with the caregivers, from which they can be motivated to participate in other ´processes of collective and individual changes. Also there’s a need to rely on facilitators (professionals and change agents) who have stronger competences on the how to be and the how to interact competences, because there’s a need to manage the psychosocial components in this group of people. Also, we must make organizational processes and the social networks stronger, this is: collective actions are required, because disability is a social fact, and so, the individual issues are just a moment in the process of inclusion of the person with disability, his family and caregiver.
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Avui en dia no es pot negar el fet que els humans són un component més de les conques fluvials i que la seva activitat afecta enormement la qualitat de les aigües. A nivell europeu, l'elevada densitat de població situada en les conques fluvials ha comportat un increment de la mala qualitat de les seves aigües fluvials. En les darreres dècades l'increment de les càrregues de nutrients en els sistemes aquàtics ha esdevingut un problema prioritari a solucionar per les administracions competents en matèria d'aigua. La gestió dels ecosistemes fluvials no és una tasca fàcil. Els gestors es troben amb què són sistemes molt complexos, donada l'estreta relació existent entre els ecosistemes fluvials i els ecosistemes terrestres que drenen. Addicionalment a la complexitat d'aquests sistemes es troba la dificultat associada de la gestió o control de les entrades de substàncies contaminants tant de fonts puntuals com difoses. Per totes aquestes raons la gestió de la qualitat de les aigües fluvials esdevé una tasca complexa que requereix un enfocament multidisciplinar. Per tal d'assolir aquest enfocament diverses eines han estat utilitzades, des de models matemàtics fins a sistemes experts i sistemes de suport a la decisió. Però, la major part dels esforços han estat encarats cap a la resolució de problemes de reduïda complexitat, fent que molts dels problemes ambientals complexos, com ara la gestió dels ecosistemes fluvials, no hagin estat vertaderament tractats. Per tant, es requereix l'aplicació d'eines que siguin de gran ajuda en els processos de presa de decisions i que incorporin un ampli coneixement heurístic i empíric: sistemes experts i sistemes de suport a la decisió. L'òptima gestió de la qualitat de l'aigua fluvial requereix una aproximació integrada i multidisciplinar, que pot ésser aconseguida amb una eina intel·ligent construïda sobre els conceptes i mètodes del raonament humà. La present tesi descriu la metodologia desenvolupada i aplicada per a la creació i construcció d'un Sistema Expert, així com el procés de desenvolupament d'aquest Sistema Expert, com el principal mòdul de raonament d'un Sistema de Suport a la Decisió Ambiental. L'objectiu principal de la present tesi ha estat el desenvolupament d'una eina d'ajuda en el procés de presa de decisions dels gestors de l'aigua en la gestió de trams fluvials alterats antròpicament per tal de millorar la qualitat de la seva aigua fluvial. Alhora, es mostra el funcionament de l'eina desenvolupada a través de dos casos d'estudi. Els resultats derivats del Sistema Expert desenvolupat, implementat i presentat en la present tesi mostren que aquests sistemes poden ésser eines útils per a millorar la gestió dels ecosistemes fluvials.
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Despite the many models developed for phosphorus concentration prediction at differing spatial and temporal scales, there has been little effort to quantify uncertainty in their predictions. Model prediction uncertainty quantification is desirable, for informed decision-making in river-systems management. An uncertainty analysis of the process-based model, integrated catchment model of phosphorus (INCA-P), within the generalised likelihood uncertainty estimation (GLUE) framework is presented. The framework is applied to the Lugg catchment (1,077 km2), a River Wye tributary, on the England–Wales border. Daily discharge and monthly phosphorus (total reactive and total), for a limited number of reaches, are used to initially assess uncertainty and sensitivity of 44 model parameters, identified as being most important for discharge and phosphorus predictions. This study demonstrates that parameter homogeneity assumptions (spatial heterogeneity is treated as land use type fractional areas) can achieve higher model fits, than a previous expertly calibrated parameter set. The model is capable of reproducing the hydrology, but a threshold Nash-Sutcliffe co-efficient of determination (E or R 2) of 0.3 is not achieved when simulating observed total phosphorus (TP) data in the upland reaches or total reactive phosphorus (TRP) in any reach. Despite this, the model reproduces the general dynamics of TP and TRP, in point source dominated lower reaches. This paper discusses why this application of INCA-P fails to find any parameter sets, which simultaneously describe all observed data acceptably. The discussion focuses on uncertainty of readily available input data, and whether such process-based models should be used when there isn’t sufficient data to support the many parameters.
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This paper describes the results and conclusions of the INCA (Integrated Nitrogen Model for European CAtchments) project and sets the findings in the context of the ELOISE (European Land-Ocean Interaction Studies) programme. The INCA project was concerned with the development of a generic model of the major factors and processes controlling nitrogen dynamics in European river systems, thereby providing a tool (a) to aid the scientific understanding of nitrogen transport and retention in catchments and (b) for river-basin management and policy-making. The findings of the study highlight the heterogeneity of the factors and processes controlling nitrogen dynamics in freshwater systems. Nonetheless, the INCA model was able to simulate the in-stream nitrogen concentrations and fluxes observed at annual and seasonal timescales in Arctic, Continental and Maritime-Temperate regimes. This result suggests that the data requirements and structural complexity of the INCA model are appropriate to simulate nitrogen fluxes across a wide range of European freshwater environments. This is a major requirement for the production of coupled fiver-estuary-coastal shelf models for the management of our aquatic environment. With regard to river-basin management, to achieve an efficient reduction in nutrient fluxes from the land to the estuarine and coastal zone, the model simulations suggest that management options must be adaptable to the prevailing environmental and socio-economic factors in individual catchments: 'Blanket approaches' to environmental policy appear too simple. (c) 2004 Elsevier B.V. All rights reserved.
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Medium range flood forecasting activities, driven by various meteorological forecasts ranging from high resolution deterministic forecasts to low spatial resolution ensemble prediction systems, share a major challenge in the appropriateness and design of performance measures. In this paper possible limitations of some traditional hydrological and meteorological prediction quality and verification measures are identified. Some simple modifications are applied in order to circumvent the problem of the autocorrelation dominating river discharge time-series and in order to create a benchmark model enabling the decision makers to evaluate the forecast quality and the model quality. Although the performance period is quite short the advantage of a simple cost-loss function as a measure of forecast quality can be demonstrated.