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Nutrient and biotic properties of mormoder and leptomoder humus forms in the coastal western hemlock zoneKlinka, Karel, Fons, Jaume, Chourmouzis, Christine January 1997 (has links)
In British Columbia, humus form identification is widely use to infer the level of plant-available soil nutrients. This identification is based on field-observable (morphological)
features. We recognize three major humu forms: Mors, Moders, and Mulls - which are differentiated according to the type of F horizon, and the presence/absence of organic
matter-enriched Ah horizons.
Mors represent humus forms where decomposition is dominated by fungi, with slow decomposition rates and accumulations of organic matter on the soil surface. Mors
are characterized by the presence of a Fm (m - mycogenous) horizon. In contrast, Mulls represent humus forms with high rates of decomposition and faunal activity resulting in
organic matter being intimately incorporated into the upper mineral soil layer instead of accumulating on its surface. Intermediate on the humus form gradient from Mors to Mull
are the Moders. Moders are similar to Mors in that they have accumulations of organic matter on the surface of the mineral soil but decomposition is not fungus dominated, so
they lack the diagnostic Fm horizon. The central concept of the Moder is represented by the Leptomoder, which is characterized by a Fz (z - zoogenous) horizon with an active
population of soil meso- and microfauna, fungal mycelia are not present or present in small amounts. When both fungal mycelia and faunal droppings can be found, but neither
clearly predominate over the other, an Fa (a - amphimorphic) horizon results. Fa horizons are characteristic of Mormoders, an integrade between Mors and Moders.
Considering the prevalence of Mormoders and Leptomoders in B.C. and the difficulties in identifying Fa horizons, the aim of this study was to determine whether the
morphological features used to differentiate these two Moder humus forms reflects differences in their physical, chemical and biotic properties.
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Biogenų n ir p išplova Lietuvos žemumų dirvožemiuose / Leaching of biogens n and p from soils of Lithuania‘ lowlandsBučienė, Angelija 05 March 2009 (has links)
Habilitacijos procedūrai teikiamoje apžvalgoje apibendrinti po disertacijos apgynimo (1984 m.) atliktų mokslinių tyrimų darbų rezultatai. Šiame darbe remiamasi autorės atliktų ir vadovautų maisto medžiagų migracijos tyrimų Lietuvos žemdirbystės institute Dotnuvoje 1992-1995 m., taip pat kartu su bendraautoriais vykdytų tyrimų 1992-2003 m. LŽI bazėje rezultatais bei 1995-1999 m. tyrimų rezultatais, gautais R.Liutkevičiaus ūkyje, vykdant tarptautinį BEAROP (Baltijos jūros aplinkosaugos nuo žemės ūkio nuotėkio taršos) projektą. Šios apžvalgos tikslas ir uždaviniai – išanalizuoti ir apibendrinti biogenų N ir P drenažo išplovos Pajūrio ir Vidurio žemumų agroekosistemų dirvožemiuose tyrimų rezultatus, paaiškinti nustatytas tendencijas, palyginti išplovos rezultatus, gautus nedidelėje drenažo aikštelėje ir didelėje ūkyje esančioje drenažo sistemoje, apskaičiuoti ir prognozuoti išplovas mišrių tradicinių ir ekologinių ūkių sąlygomis bei numatyti užduotis tolesniems tyrimams. Šioje apžvalgoje apibendrinama tyrimų medžiaga apima 19 mokslinių straipsnių, vieną monografiją ir tarptautinio projekto ataskaitą, kurie buvo paskelbti 1995-2008 m. Dauguma straipsnių parengta kartu su kitais bendraautoriais (vienuolikoje iš jų autorė buvo pirmoji). Publikuotos medžiagos pagrindu buvo daryti pranešimai daugiau kaip 19 mokslo renginių (konferencijose, seminaruose, simpoziume) tiek Lietuvoje, tiek užsienyje. / The results of scientific research conducted since acquisition of the Ph.D. in 1984 are reviewed in this survey for habilitation procedure. The nutrient migration research was conducted and supervised by author and performed at Lithuanian institute of Agriculture (LIA) in Dotnuva in 1992-1995, together with other researchers was conducted in the base of LIA in 1995-2003, and in the farm of R.Liutkevičius in 1995-1999, according to the tasks of international BEAROP project (Baltic Environment and Agricultural Runnof Project). The aim and tasks of this survey – to analyse and summarise the results of nutrients N and P leaching from soils of agroecosystems of Seashore and Middle Lithuania lowlands, to explain the trends, to compare the leaching results from small and big drainage system (at the farm), to estimate and forecast the leaching of nutrients under conditions of conventional and ecological farms and to foresee the tasks for the future research. The review material covers 1995-2008 and 19 scientific papers, 1 monograph and 1 international raport published during that period. The most of papers were prepared together with co-authors, but in 11 of them the author was the first. On the base of material obtained, more than 19 presentations were made at different scientific events (conferences, seminars, symposium) in Lithuania as well as in other countries.
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Treatment of Water-borne Nutrients, Pathogens, and Pharmaceutical Compounds using Basic Oxygen Furnace SlagHussain, Syed January 2013 (has links)
Phosphorus (P) is one of the essential nutrients for living organisms; however, excess P in aquatic systems often causes environmental and ecological problems including eutrophication. Removal of P from domestic wastewater, industrial wastewater, and agricultural organic-waste systems is required to minimize loading of P to receiving water bodies. A variety of sorbents or filter materials have previously been evaluated for P removal, including natural materials, industrial byproducts, and synthetic products. Among these materials industrial byproducts were reported as most effective. However, only a few of these studies were based on field experiments. Pharmaceutically active compounds (PhACs) and acesulfame-K (an artificial sweetener) are emerging contaminants observed in wastewater. The removal of PhACs in conventional wastewater treatment systems has been studied; however, few studies on alternative treatment systems are available. Studies related to the removal of acesulfame-K are even more limited. This thesis was focused on evaluation of basic oxygen furnace slag (BOFS), a byproduct from the steel manufacturing industry, as a potential reactive media for P removal from surface water and wastewater. The removal of PhACs and acesulfame-K in wastewater treatment systems containing BOFS as a treatment component was also evaluated.
The effectiveness of BOFS for removing P from lake water was evaluated in a three year pilot-scale hypolimnetic withdrawal P treatment system at Lake Wilcox, Richmond Hill, Ontario. Phosphate concentrations of the hypolimnion water ranged from 0.3 to 0.5 mg L-1. About 83-100% P was removed during the experiment. The reactive mixtures were changed each year to improve the performance of the treatment system. Elevated pH (9-12) at the effluent of the treatment system was adjusted by sparging CO2(g) to near neutral pH. Elevated Al was removed through this pH adjustment. Elevated concentrations of V were removed in a column containing 5 wt% zero valent iron (ZVI) mixed with sand (0.5 m3) at the end of the BOFS based column. Removal of P in the BOFS based media is attributed to adsorption and co-precipitation at the outer layer of BOFS. Geochemical modeling results showed supersaturation with respect to hydroxyapatite, ß-tricalciumphosphate, aragonite, and calcite. Solid phase analyzes of the BOFS based reactive media collected after completion of the year 2 experiment (spent media) through combination of scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and X-ray absorption near edge structure spectroscopy (XANES) support the presence of calcium phosphate minerals on the outer layer of the spent media.
A multistep wastewater treatment experiment was carried out in an indoor facility at the Center for Alternative Wastewater Treatment, Fleming College, Lindsay, Ontario, Canada. This experiment evaluated the removal of P, ammonia, cBOD5, COD, E. coli, total coliform, and trace metals in a series of treatment cells including a mixing cell, a vertical subsurface flow aerobic cell, a vertical subsurface flow P treatment cell containing BOFS, and a horizontal subsurface flow anaerobic cell. About 97-99% removal of P, NH3, cBOD5, E. coli, and total coliform; and ~72% removal of COD were achieved in the treatment system. The mixing cell and the aerated cell reduced the concentrations of P, ammonia, cBOD5, E. coli, and total coliform significantly and the P treatment cell provided additional treatment. However, the primary objective of the P treatment cell was to reduce P concentrations to the acceptable range according to the water quality guidelines. The P treatment cell had successfully fulfilled this objective. Elevated concentration of Al and V were also observed in the P treatment cell effluent. The concentration of Al decreased to below the guideline value of 0.075 mg L-1 after introducing a pH adjustment unit between the P treatment cell and the anaerobic cell. The concentration of V was decreased in the anaerobic cell effluent. However, the effluent concentration of V was much higher than the guideline value. Geochemical speciation modeling results showed supersaturation with respect to hydroxyapatite, ß-tricalciumphosphate, aragonite and calcite along the flow path. Accumulation of P on the outer layer of the spent BOFS media was identified by energy dispersive X-ray spectroscopy (EDX). Although X-ray photoelectron spectroscopy (XPS) can provide information to a depth of 5-7 nm from the outer layer of the spent media, both Ca and P were positively identified in some of the samples. Accumulation of P at the edge of the grains of the spent media was clearly identified on the element map of polished cross-sections and corresponding FTIR spectra. The phosphate and carbonate functional groups were identified by the distribution of different vibrational frequencies through FTIR spectroscopy. The presence of calcite and hydroxyapatite were inferred based on the wave numbers assigned for these minerals in the literature. Finally, X-ray absorption near edge structure spectroscopy (XANES) on the outer layer samples from the spent BOFS media and corresponding linear combination fitting analysis indicated the presence of ß-tricalciumphosphate, hydroxyapatite, and calcium phosphate dibasic.
Based on the observations from the indoor wastewater treatment experiment, a multistep demonstration-scale outdoor wastewater treatment experiment was conducted to investigate the applicability of the integration of the P treatment technology and engineered wetland technology at a relatively large scale prior to a full-scale field installation. The anaerobic treatment cell was not included in this outdoor system because this unit did not efficiently remove ammonia and metals (e.g. V) from the Cell 4 effluent in the indoor system. A 10 cm layer of zero valent iron was placed at the bottom part of the down flowing P treatment cell to address the elevated V in the P treatment cell effluent observed in the indoor system and also to treat PhACs in the effluent. More than 99% removal of P, E. coli, and total coliform; >82, >98, and >76% removal of ammonia, cBOD5, and COD were achieved in this treatment system. The effluent pH (10.88±1.47) was neutralized and the concentration of V remained < 0.006 mg L-1. The Al concentration was adjusted to <0.075 mg L-1 with the neutralization of pH. Geochemical speciation modeling results showed the supersaturation of hydroxyapatite, ß-tricalciumphosphate, octatricalciumphosphate, aragonite, and calcite. The FTIR and XANES spectra showed the presence of calcium phosphate minerals on the outer layer of the spent media.
Removal of the PhACs, including caffeine, ibuprofen, carbamazepine, naproxen, and sulfamethoxazole, and acesulfame-K was monitored in the demonstration-scale outdoor wastewater treatment system, which consisted of five different treatment cells including a horizontal subsurface flow constructed wetland, a vertical subsurface flow aerated cell, a vertical subsurface flow BOFS cell, and a pH neutralization unit. Significant removal of caffeine (>75%) and ibuprofen (50-75%), and moderate removal of sulfamethoxazole and naproxen (25-50%) were observed. The removal of carbamazepine was less effective with <25% removal observed. Acesulfame-K was also persistent along the flow path with <25% removal.
This study demonstrated that removal of P from lake water and wastewater in excess of 95% could be achieved using BOFS as a reactive media. Integration of this media into an engineered wetland system enhances its performance in removing nutrients and other wastewater contaminants.
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Establishing Organic Blackcurrants in Atlantic CanadaHobson, David W. 12 April 2012 (has links)
A study on Prince Edward Island was initiated to assess the impact of organic fertility amendment rate and timing treatments and deflowering on the growth, yield, and berry size and soluble solids, and plant and soil available nutrients of blackcurrants (Ribes nigrum L cv. Titania.). Plants at the site with lower leaf P and K showed lower growth and yield (492-2540 kg ha-1) than the other site (3935-5016 kg ha-1No significant differences were found in final size or 2011 yield at the site with larger bushes, while at the other site the medium spring fertility treatment gave the greatest growth and yield, followed by the high spring fertility treatment. Deflowering increased yield but not growth at the site with recommended ranges of leaf P and K; at the site with P and K deficiencies, growth increased in 2010 and 2011. There was no interaction between deflowering and amendment timing.
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BIORETENTION GARDENS FOR THE REMOVAL OF NITROGEN AND PHOSPHOROUS FROM URBAN RUNOFFRandall, Mark 12 September 2011 (has links)
Bioretention gardens are stormwater management practices that offer numerous water quantity and quality benefits. However, previous studies have reported inconsistent removal of nitrogen and phosphorous in these systems. The first phase of this research involved the construction and monitoring of ten vegetated, mesoscale, bioretention cells in a field setting to provide a comparison of the performance of five alternative designs intended to provide nutrient removal. Results indicated that concentrations of total nitrogen and total phosphorous may be reduced by up to 53 and 79%, respectively, in specially designed bioretention gardens. In the second phase of the research, a GIS-based site selection tool was used to identify areas suitable for bioretention implementation based on physical site requirements. Applying this tool to selected urban catchments demonstrated that bioretention gardens may be integrated into existing urban landscapes on a scale large enough to accommodate runoff and associated nutrient loads from small (<15mm) storms.
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Lietuvos edukologijos universiteto ketvirto kurso kūno kultūros specialybės studentų fizinis aktyvumas ir mitybos įpročiai / Physical activity and eating habits of fourth-year physical education students’ in Lithuanian University of Educational SciencesŠčerbakova, Sabina 06 August 2013 (has links)
Tyrėjai nustatė, kad studentų mityba yra nereguliari, nesilaikoma mitybos režimo, nustatytas maisto medžiagų disbalansas. A. Norkaus (2012) teigimu nemažai studentų mano, kad jų amžiuje sveikata rimtai dar rūpintis nereikia. Tačiau Lietuvos edukologijos universiteto kūno kultūros IV kurso studentai pagal studijų programą turi nemažą fizinį krūvį, privalo lankyti treniruotes, o daugelis studentų dar ir dirba. Toks didelis fizinis krūvis reikalauja atitinkamos mitybos, kad būtų padengtos energijos sąnaudos. Netinkama, neracionali, nesubalansuota mityba gali ilgainiui sutrikdyti studentų sveikatą. R. Stuko (1999) teigimu mityba priklauso nuo žmogaus žinių apie mitybą ir jos poveikį sveikatai.
Šio darbo problema: tinkamai organizuota mityba patenkina energinius ir plastinius organizmo poreikius, padeda išlaikyti fizinį darbingumą, pašalina nuovargį, greičiau atgaunamos jėgos (Portugalov, 2001). Dauguma sportuojančiųjų stengiasi maitintis racionaliai, nors ne visada jiems pasiseka. Teisingai sudaryti maisto racioną dažnai apsunkina reklama raginanti vartoti vienus ar kitus maisto produktus. Netgi žinodami tam tikrų produktų grupių vartojimo privalumus studentai nesugeba tinkamai įvertinti jų kiekių.
Todėl buvo iškelta hipotezė: įgytos žinios, didelis fizinis aktyvumas turėtų skatinti formuotis sveikesnius sportuojančių studentų mitybos įpročius.
Naujumas ir reikšmingumas. Atlikti mokslininkų tyrimai susiję su mityba ir fiziniu aktyvumu apima atskiras jų dalis. Tokio pobūdžio... [toliau žr. visą tekstą] / The researchers determined that the student's diet is irregular, and imbalanced. A. Norkus (2012), stated that according to the number of students thoughts, health care is not very important at their age. However, the students of Lithuanian University of educational according their study programme have a big physical load, they must attend sport practice classes and many students have their jobs. Such a great physical activity required by the relevant nutrition to cover energy costs. Unbalanced diet may eventually interfere with the student's health. R. Stukas (1999) stated that nutrition is dependent on human knowledge about nutrition and its impact on health.
The problem: the proper diet has to meet the needs of the organism, energetic, and plastic requirements on their organism, helps to maintain physical working capacity, to remove fatigue (Portugalov, 2001). Most of the physically active people are trying to keep nbalance in their nutrition, althou not always they are succeded. Making a proper food rations are often compounded by advertisements which offer one or other food products. Even knowing the advantages of certain groups of products, students often failed to assess them properly.
Hypothesis: high levels of physical activity should promote the development of healthier eating habits of students.
Conducting scientific studies related to diet and physical activity is often separated. This kind of research is conducted by: V. Žydžiūnaitė, S. Jonušaitė (2006), A... [to full text]
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A comparative paleolimnological assessment of the influences of early Arctic population groups on freshwater ecosystems from southern Baffin Island, NunavutMCCLEARY, KATHRYN 04 October 2011 (has links)
Recent paleolimnological research in the eastern Canadian high Arctic on the ecological impact of the Thule c.1000-1500 AD has documented the influence of prehistoric anthropogenic activities. Six lake and pond sites (three pairs) on the south-western coast of Baffin Island, Nunavut, were used to compare impacted and non-impacted sites in the southern-most region of Thule occupation, as well as to compare Thule occupation sites with sites occupied by another early Arctic population group, the Dorset. Tanfield 1 and Tanfield 2 (impacted and control, respectively) are adjacent to several multiple-occupation Dorset sites on Cape Tanfield; Juet 1 and 2 (impacted and control, respectively) are adjacent to a short-term occupation Dorset site on Juet Island; McKellar 1 is adjacent to a multiple-occupation Thule site near McKellar Bay. A nearby site (McKellar 2) was also studied, but it was clearly an anomalous, eutrophic site, rather than a control for McKellar 1. Diatom assemblages and sedimentary 15N profiles were analyzed in sediment cores from all study sites. Selected paired sediment intervals were AMS radiocarbon dated using both humic acids and terrestrial macrofossils in an attempt to establish basal dates for each core. Significant differences between several of the paired AMS radiocarbon dates serve as a cautionary note for dating Arctic sediments using either humic acids or terrestrial macrofossils. Paleolimnological analyses revealed that at both multiple-occupation sites (Tanfield 1 and McKellar 1), the activities of the Dorset and the Thule influenced lake ecology, while at the short-term occupation site (Juet 1), the Dorset occupation was not sufficiently large to have a discernible impact. McKellar 1 showed a greater impact compared to Tanfield 1, consistent with the intense marine mammal hunting by Thule at the former, compared to the moderate marine mammal hunting by Dorset at Tanfield 1. The origin of marine-derived nutrients at McKellar 2 could not be ascertained with certainty. The influence of early Arctic population groups remains obvious in present-day nutrient- and production-related water chemistry variables. This research points to the value of collaborations between paleolimnologists and archaeologists and may provide insight into the future implications of current anthropogenic activities in the Arctic. / Thesis (Master, Biology) -- Queen's University, 2011-10-04 15:52:18.29
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Macroalgae in tropical seascapes : regulating factors and functions in the coastal ecosystemLilliesköld Sjöö, Gustaf January 2010 (has links)
Although macroalgae usually are inconspicuous on pristine coral reefs, they often thrive on reefs that are subjected to various types of anthropogenic disturbance. This thesis consists of five papers and investigates how biomass and composition of macroalgal communities on coral reefs are affected by regulating factors, such as nutrient availability, herbivory, substrate availability and hydrodynamic forces. In addition, ecological functions and potential impacts of both wild and farmed macroalgal communities are evaluated. Paper I describes a method for using macroalgal tissue nutrient concentrations as bioindicator for nutrient availability, with the possibility to map nutrient loading from larger coastal cities. Papers II and III are manipulative studies comparing top-down and bottom-up regulation of macroalgal communities, where herbivore consumption seems to be the main regulator of biomass whereas nutrient availability mainly influences community composition. Exclosure of large-bodied herbivores had a positive influence on algal biomass in both studies, and during different climatic periods. Paper III also includes the influence of hydrodynamic forces on algal community biomass and structure by comparing a reef crest and a back reef-habitat. Alterations of top-down and bottom-up regulation generally had a stronger effect within the protected back reef-habitat, suggesting that such environments may be more sensitive to anthropogenic influence. Paper IV confirms the general conclusions from papers II and III by studying macroalgal biomass and composition on reef sites with different environmental prerequisites. This study also supports the notion that herbivorous fish can suppress accumulation of macroalgal biomass if substrate availability is low, but not where coral cover is reduced and plenty of substrate is open to macroalgal colonization. The study also found a large temporal variation of macroalgal standing stock and associated nutrients at sites with low top-down regulation. Paper V evaluates potential impacts of seaweed farming on coral reefs and nutrients in the seascape by experimentally studying growth, survival and nutrient binding capacity of Eucheuma denticulatum. This study showed that seaweed farms counteract eutrophication through nutrient extraction and that the risk of farmed algae colonizing local reefs seems to be small as they were rapidly consumed. In conclusion, the studies in this thesis contribute to the understanding of macroalgal regulation and function in tropical seascapes, thereby adding to the knowledge base for coastal management. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript. Paper 5: Manuscript.</p>
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Macroalgal community dynamics on coral reefs : Implications for managementMörk, Erik January 2011 (has links)
Although rather inconspicuous on healthy coral reefs, macroalgae form the basis of coral food webs. Today, macroalgae are generally increasing and many reefs undergo transitions from coral to macroalgal dominance resulting from e.g. enhanced nutrient loading or increased fishing. This thesis aims to investigate the relative importance of top-down and bottom-up regulation, and different herbivore types, on macroalgal distribution, fecundity and community composition on coral reefs. Papers I and II indicate that macroalgal abundance in a coral reef system is largely governed by top-down regulation through grazing by herbivores, while bottom-up regulation through enhanced nutrient availability rather influence algal species composition. Paper II also shows that these regulating effects are not as evident in an area with relatively strong water motion, suggesting that impacts of anthropogenic disturbance may be site-specific. Paper III shows that herbivory is an important factor influencing macroalgal growth and subsequent reproduction. Furthermore, Paper IV and V conclude that efficiency in removing macroalgal biomass is dependent on the type of dominant herbivore, where sea urchins seem to be more effective than fish. Paper IV indicates a seasonal variation in macroalgal biomass and distribution in a small geographic scale but with relatively high temporal resolution. Paper V on the other hand shows these same effects, but with a focus on geographic variation, including a large part of the East African region, as well as between year temporal variations in Kenya. Together, results from the two latter studies indicate that herbivory by fish may not be able to prevent a macroalgal bloom in a degraded system where substrate availability for algal colonization is high, but that it may still facilitate coral recovery over time. Thus, a large algal biomass may not necessarily indicate a reef beyond the possibility of recovery. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Accepted. Paper 4: Manuscript. Paper 5: Manuscript.</p>
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Understanding Variation in Water Quality using a Riverscape PerspectiveFranklin, Hannah Mayford January 2010 (has links)
With the increasing degradation of rivers worldwide, an understanding of spatial and temporal patterns in freshwater quality is important. Water quality is highly variable in space and time, yet this is largely overlooked at the scale of stream catchments. I employed a landscape ecology approach to examine the spatial patterning of water quality in complex, impacted stream networks on the Canterbury Plains of the South Island of New Zealand, with the goal of understanding how land-use effects proliferate through stream systems.
In particular, I used “snapshot” sampling events in conjunction with spatial modelling and longitudinal profiles to investigate the ways in which spatial and environmental factors influence the variability of water quality in stream networks. Spatial eigenfunction analyses showed that distance measures, which took into account variable connectivity by flow and distance along the stream between sites, explained more spatial variance in water quality than traditional distance metrics. Small upstream reaches were more spatially and temporally variable than main stems (under summer base-flow conditions). The extent of spatial variation in water quality differed between stream networks, potentially depending on linkages to groundwater and the surrounding landscape. My results indicated that the water quality of headwater streams can have a disproportionate influence over water quality throughout an entire network.
I investigated spatio-temporal patterns in water quality more intensively in one stream network, the Cam River, in which I found consistent spatial pattern through time. The relative balance between nutrient inputs (pollution and groundwater) and in-stream conditions influenced the spatial pattern of water quality, as well as that of several ecosystem processes which I measured simultaneously. The spatially intensive and explicit approach has allowed identification of key factors controlling water quality and ecosystem processes throughout the Cam River. This research highlights the importance of taking a spatially explicit approach when studying stream water quality and that such an approach could be insightful and will contribute to solving current stream management problems.
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