La ricerca è stata possibile a causa di finanziamento da progetto di valutazione di effetti di conservazione (CEAP). Siamo particolarmente grati per l'autorizzazione di accesso al sito dai produttori, la ricerca di assistenza da parte dei membri della unità di ricerca di USDA-ARS-Delta acqua gestione e analisi dei campioni di personale presso la struttura di ricerca di ecotossicologia, Arkansas State University. Parte di questa ricerca è stata sostenuta da un appuntamento per il programma di partecipazione di ARS, amministrato dall'Istituto Oak Ridge per scienza e formazione (ORISE) attraverso un accordo tra agenzie tra l'US Department of Energy e la USDA. ORISE è gestito da ORAU DOE contratto numero DE-AC05-06OR23100. Tutte le opinioni espresse in questo documento sono dell'autore e non riflettono necessariamente le politiche e le vedute di USDA, ARS, DOE o ORAU/ORISE.

<ol>
	<li>Pellerin, B. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Emerging+Tools+for+Continuous+Nutrient+Monitoring+Networks:+Sensors+Advancing+Science+and+Water+Resources+Protection.">Emerging Tools for Continuous Nutrient Monitoring Networks: Sensors Advancing Science and Water Resources Protection.</a> J Am Water Resour Assoc. 52 (4), 993-1008 (2016).</li><li>Rozemeijer, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+and+Evaluation+of+a+New+Passive+Sampler+for+Measuring+Average+Solute+Concentrations+in+a+Catchment+Scale+Water+Quality+Monitoring+Study.">Application and Evaluation of a New Passive Sampler for Measuring Average Solute Concentrations in a Catchment Scale Water Quality Monitoring Study.</a> Environ Sci Tech. 44 (4), 1353-1359 (2010).</li><li>Cassidy, R., Jordan, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Limitations+of+instantaneous+water+quality+sampling+in+surface-water+catchments:+Comparison+with+near-continuous+phosphorus+time-series+data.">Limitations of instantaneous water quality sampling in surface-water catchments: Comparison with near-continuous phosphorus time-series data.</a> J. Hydrol. 405 (1-2), 182-193 (2011).</li><li>Facchi, A., Gandolfi, C., Whelan, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+comparison+of+river+water+quality+sampling+methodologies+under+highly+variable+load+conditions.">A comparison of river water quality sampling methodologies under highly variable load conditions.</a> Chemosphere. 66 (4), 746-756 (2007).</li><li>Hamilton, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Global hydrological monitoring industry trends. , (2012).</li><li>Aryal, N., Reba, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transport+and+transformation+of+nutrients+and+sediment+in+two+agricultural+watersheds+in+Northeast+Arkansas.">Transport and transformation of nutrients and sediment in two agricultural watersheds in Northeast Arkansas.</a> Agric Ecosyst Environ. 236, 30-42 (2017).</li><li>National Research Council (U.S.). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Confronting the nation's water problems: The role of research. , (2004).</li><li>LMRRA (Lower Mississippi River Resource Assessment). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Final Assessment in Response to Section 402 of WRDA 2000 Public Review Draft. , (2015).</li><li>MWNTF (Mississippi River/Gulf of Mexico Watershed Nutrient Task Force). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> New Goal Framework. , (2008).</li><li>Reba, M. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+statewide+network+for+monitoring+agricultural+water+quality+and+water+quantity+in+Arkansas.">A statewide network for monitoring agricultural water quality and water quantity in Arkansas.</a> J. Soil Water Conserv. 68 (2), 45a-49a (2013).</li><li>Duncan, D., Harvey, F., Walker, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Australian Water Quality Centre. , (2007).</li><li>Hamilton, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The 5 essential elements of a hydrological monitoring program. , (2012).</li><li>Wagner, R. J., Boulger, R. W., Oblinger, C. J., Smith, B. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> , (2006).</li><li>World Metorological Organization. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Manual on Stream Gauging Volume I-Fieldwork. , (2010).</li><li>American Public Health Association, American Water Works Association, &amp; Water Environment Federation. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Standard methods for the examination of water &amp; wastewater. , (2005).</li><li>ASTM (American Society of Testing and Materials) D3977-97. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Standard test methods for determining sediment concentration in water samples. , (1997).</li><li>O'Connor, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+temporal+and+spatial+distribution+of+dissolved+oxygen+in+streams.">The temporal and spatial distribution of dissolved oxygen in streams.</a> Water Resour Res. 3 (1), 65-79 (1967).</li><li>Dabney, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cover+crop+impacts+on+watershed+hydrology.">Cover crop impacts on watershed hydrology.</a> J Soil Water Conserv. 53 (3), 207-213 (1998).</li><li>Udawatta, R. P., Motavalli, P. P., Garrett, H. E., Krstansky, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nitrogen+losses+in+runoff+from+three+adjacent+agricultural+watersheds+with+claypan+soils.">Nitrogen losses in runoff from three adjacent agricultural watersheds with claypan soils.</a> Agric Ecosyst Environ. 117 (1), 39-48 (2006).</li></ol>

Gli autori non hanno nulla a rivelare.

Nel complesso, il controllo continuo di sostanze nutritive e sedimenti presenta parecchi vantaggi sopra monitoraggio utilizzando il metodo di campionamento della gru a benna. Processi di qualità idrologici e acqua sono interessati da precipitazioni sopra un arco di tempo molto breve. Gli utenti possono ottenere alti risoluzione temporale dati su sostanze nutritive e sedimento per studiare problemi complessi. Altri parametri di qualità dell'acqua, come conducibilità, pH, temperatura e, possono essere ottenuti contempor...

Monitoraggio della qualità dell'acqua fornisce informazioni sulle concentrazioni di sostanze inquinanti a diverse scale spaziali, in base alle dimensioni dell'area che contribuisce, che può variare da una trama o un campo a un punto di svolta. Questo controllo avviene in un periodo di tempo, come un singolo evento, un giorno, una stagione o un anno. Le informazioni che ha raccolse dal monitoraggio qualità dell'acqua, principalmente relativi alle sostanze nutritive (ad es., azoto e fosforo) e sedimenti, possono essere utilizzate per: 1) comprendere i processi idrologici, trasporto e trasformazione degli inquinanti nei flussi, come fossati di drenaggio agricolo; 2) valutare l'efficacia delle pratiche di gestione applicate allo spartiacque per ridurre il carico di nutrienti e di sedimento e di aumentare la qualità dell'acqua; 3) valutare la consegna di sedimenti e nutrienti all'acqua a valle; e 4) migliorare la modellazione delle sostanze nutrienti e sedimento per capire l'idrologico e processi di qualità che determinano il trasporto di sostanze inquinanti e le dinamiche sopra la gamma di scale temporali e spaziali delle acque.
Questa informazione è cruciale per il ripristino dell'ecosistema acquatico, pianificazione sostenibile e la gestione delle risorse di acqua1.
Metodo il più comunemente usato per nutriente e monitoraggio dei sedimenti in un bacino idrografico è afferrare campionamento. Gru a benna campionamento rappresenta accuratamente una concentrazione istantanea al momento del campionamento2. Possa rappresentare anche una variazione delle concentrazioni di inquinanti con tempo se campionamento frequente è fatto. Tuttavia, campionamento frequente è tempo intensivo e costoso, spesso rendendo impraticabile2. Inoltre, afferrare campionamento può sotto- o sopravvalutare le concentrazioni di inquinante reale di fuori il tempo di campionamento2,3,4. Di conseguenza, carichi calcolate utilizzando tali concentrazioni potrebbero non essere accurati.
In alternativa, un monitoraggio continuo fornisce informazioni accurate e tempestive sulla qualità dell'acqua in un intervallo di tempo predeterminato, ad esempio un minuto, un'ora o un giorno. Gli utenti possono selezionare gli intervalli di tempo appropriati in base alle loro esigenze. Monitoraggio continuo consente i ricercatori, progettisti e Manager ottimizzare la raccolta del campione; sviluppare e monitorare metriche tempo integrato, quali carichi giornalieri massimi totale (TMDLs); valutare l'uso ricreativo del corpo idrico; valutare le condizioni di flusso basale; e spazialmente e temporalmente valutare la variazione delle sostanze inquinanti a determinare rapporti di causa-effetto e sviluppare un piano di gestione5,6. Monitoraggio continuo di sostanze nutritive e sedimento ha recentemente ricevuto attenzione aumentata dovuto gli avanzamenti nella tecnologia informatica e sensore, il miglioramento delle capacità dei dispositivi di archiviazione e i crescenti requisiti di dati necessari per lo studio dei processi più complessi 1 , 5 , 7. in un'indagine globale di oltre 700 professionisti di acqua, l'uso di multi-parametro sondes aumentata dal 26% al 61% dal 2002 al 2012 e dovrebbe raggiungere il 66% entro il 20225. Nella stessa indagine, 72% degli intervistati ha indicato la necessità per l'espansione della loro rete di monitoraggio per soddisfare i propri dati ha bisogno di5. Il numero di stazioni in una rete di monitoraggio e il numero delle variabili monitorate per ogni stazione nel 2012 si prevede di aumentare di 53% e 64%, rispettivamente, entro il 20225.
Tuttavia, continuo dell'acqua qualità e quantità di monitoraggio nei bacini agricoli è impegnativo. Eventi di pioggia grande mondare i sedimenti e macrofite, contribuendo all'accumulo di sedimenti alto carico e detriti in sensori e sonde. Il deflusso di eccesso di azoto e fosforo applicato a campi agricoli crea le condizioni ideali per la crescita di organismi microscopici e macroscopici e per la formazione di incrostazioni di instream sensori e sonde, soprattutto durante l'estate. Accumulo di incrostazioni e sedimenti può causare sensori fallire, deriva e produrre dati inaffidabili. Nonostante queste sfide, più fine risoluzione temporale (come basso secondo minuto) dati sono richiesti per studiare i processi di deflusso e la contaminazione di origine non-punto, come essi sono influenzati dalle caratteristiche del bacino idrografico (ad esempio, le dimensioni, terreno, pendenza, ecc. ) e la tempistica e l'intensità di pioggia7. Osservazione del campo di attenzione, frequente calibrazione e corretta pulizia e manutenzione può garantire buona qualità dati dai sensori e sonde, anche a una risoluzione di tempo.
Discutiamo qui, un metodo per l' in situ continuo monitoraggio dei due bacini agricoli utilizzando acqua di multi-parametro qualità sondes, zona-velocità e sensori di pressione trasduttore e autocampionatori; loro taratura e manutenzione sul campo; ed elaborazione dei dati. Il protocollo viene illustrato il modo in cui può essere eseguita il monitoraggio della qualità dell'acqua continua. Il protocollo è generalmente applicabile al continuo dell'acqua qualità e quantità di monitoraggio a qualsiasi tipo o dimensione di spartiacque.
Il protocollo è stato effettuato in Northeast Arkansas nel bacino del piccolo fiume Fossati (HUC 080202040803, area2 km 53,4) e Lower St. Francis Basin (HUC 080202030801, area2 km 23,4). Questi due bacini idrografici vuotano nel affluenti del fiume del Mississippi. Un'esigenza di monitoraggio affluenti del fiume del Mississippi è stata identificata dal comitato di conservazione inferiore di fiume del Mississippi e il Golfo del Messico ipossia Task Force per sviluppare un piano di gestione del bacino idrografico e registrare lo stato di avanzamento delle attività di gestione 8 , 9. Inoltre, questi bacini sono caratterizzati come bacini di messa a fuoco per la United States Department of Agriculture-Natural Resources Conservation Service (USDA-NRCS), sulla base del potenziale di riduzione dell'inquinamento dei sedimenti e degli elementi nutritivi e per migliorare la qualità di acqua10. Monitoraggio di bordo di campo avviene in questi bacini idrografici come parte di tutto lo stato del Mississippi River Basin sano spartiacque iniziativa (MRBI) rete11. Più dettagli dei bacini (cioè, posizioni di siti, caratteristiche del bacino idrografico, ecc.) sono forniti in Aryal e Reba (2017)6. In breve, il piccolo bacino di fossati ha prevalentemente limo terriccio terreni e cotone e soia sono le colture principali, mentre il Lower St. Francis Basin ha principalmente il terreno argilloso Sharkey, e riso e soia sono le colture principali. A ogni bacino idrografico, in situ continuo acqua quantità e qualità (cioè, temperatura di scarico, pH,, torbidità, conducibilità, nitrato e ammonio) di monitoraggio è stato effettuato in tre stazioni nel mainstream usando questo protocollo per comprendere la variabilità spaziale e temporale dei carichi inquinanti e i processi idrologici. Inoltre, i campioni di acqua settimanali sono stati raccolti e analizzati per sedimenti sospesi concentration.

<table border="0" cellpadding="0" cellspacing="0" width="812">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:149px;">Multiparameter sonde</td>
			<td style="width:109px;">Hach Hydrolab</td>
			<td style="width:135px;">DS5X</td>
			<td style="width:419px;">measures temperature, pH, conductivity, dissolved oxygen, nitrate, ammonium, turbidity</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:149px;">Area velocity flow module and sensor</td>
			<td style="width:109px;">Teledyne Isco</td>
			<td style="width:135px;">2150</td>
			<td style="width:419px;">measures average stream velocity and flow depth, and calculates flow rate and total flow based on provided cross-section area of the ditch. Stored data can be downloaded directly to computer.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:149px;">Automatic portable water sampler</td>
			<td style="width:109px;">Teledyne Isco</td>
			<td style="width:135px;">ISCO 6712</td>
			<td style="width:419px;">automatically samples water in the set interval or in conjunction with flow module and sensor</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:149px;">Pressure Transducer</td>
			<td style="width:109px;">In-situ</td>
			<td style="width:135px;">Rugged Troll 100</td>
			<td style="width:419px;">measures presure, level and temperature in the water. Stored data can be directly downloaded to the computer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:149px;">Portable flow meter</td>
			<td style="width:109px;">Flo-mate (Hach)</td>
			<td style="width:135px;">Marsh-McBirney 2000</td>
			<td style="width:419px;">For manual discharge measurement</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:149px;">Battery, 12 v, rechargeable</td>
			<td style="width:109px;">UPG</td>
			<td style="width:135px;">UB 1270</td>
			<td style="width:419px;">To power sonde</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:149px;">Battery, 12 v, rechargeable</td>
			<td style="width:109px;">Interstate Batteries</td>
			<td style="width:135px;">SRM 27</td>
			<td style="width:419px;">Lead acid battery to power autosampler</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Solar panel</td>
			<td style="width:109px;">Alt E</td>
			<td style="width:135px;">ALT20-12P</td>
			<td style="width:419px;">To recharge battery at the site</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">C-8 batteries</td>
			<td style="width:109px;"></td>
			<td style="width:135px;"></td>
			<td style="width:419px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:149px;">Calibration standards</td>
			<td style="width:109px;">Hach or Fisher Scientific</td>
			<td style="width:135px;">mulitple</td>
			<td style="width:419px;">Standards of pH (4,7,10), conductivity (1412 uS/cm), nitrate (5 and 50 mg/L), ammonium (5 and 50 mg/L), and turbidity (50,100,200 NTU)</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">High nitrate standard</td>
			<td style="width:109px;">Hach</td>
			<td style="width:135px;">013810HY</td>
			<td style="width:419px;">50 mg/L</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Low nitrate standard</td>
			<td style="width:109px;">Hach</td>
			<td style="width:135px;">013800HY</td>
			<td style="width:419px;">5 mg/L</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">High ammonium standard</td>
			<td style="width:109px;">Hach</td>
			<td style="width:135px;">002588HY</td>
			<td style="width:419px;">50 mg/L</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Low ammonium standard</td>
			<td style="width:109px;">Hach</td>
			<td style="width:135px;">002587HY</td>
			<td style="width:419px;">5 mg/L</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Turbidity standard</td>
			<td style="width:109px;">Fisher scientific</td>
			<td>R8819050-500G</td>
			<td style="width:419px;">50 NTU</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Turbidity standard</td>
			<td style="width:109px;">Fisher scientific</td>
			<td>88-061-6</td>
			<td style="width:419px;">100 NTU</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Turbidity standard</td>
			<td style="width:109px;">Fisher scientific</td>
			<td>R8819200500 C</td>
			<td style="width:419px;">200 NTU</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Potassium chloride salt pellets</td>
			<td style="width:109px;">Hach</td>
			<td style="width:135px;">005376HY</td>
			<td style="width:419px;">to maintain electrolyte for pH electrode</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Potassium chloride standard</td>
			<td style="width:109px;">Fisher scientific</td>
			<td style="width:135px;">5890-16</td>
			<td style="width:419px;">1412 us/cm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Buffer solution, pH 4</td>
			<td style="width:109px;">Fisher scientific</td>
			<td style="width:135px;">SB99-1</td>
			<td style="width:419px;">for pH sensor calibration</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Buffer solution, pH 7</td>
			<td style="width:109px;">Fisher scientific</td>
			<td style="width:135px;">SB108-1</td>
			<td style="width:419px;">for pH sensor calibration</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Buffer solution, pH 10</td>
			<td style="width:109px;">Fisher scientific</td>
			<td style="width:135px;">SB116-1</td>
			<td style="width:419px;">for pH sensor calibration</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Silicon sealant</td>
			<td style="width:109px;">Hach</td>
			<td style="width:135px;">00298HY</td>
			<td style="width:419px;">For sealing sensor battery cover water tight</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:149px;">All purpose cleaner</td>
			<td style="width:109px;">Sunshine Makers Inc</td>
			<td style="width:135px;">Simple green</td>
			<td style="width:419px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Wipes</td>
			<td style="width:109px;">Kimberly-Clark</td>
			<td style="width:135px;"></td>
			<td style="width:419px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">L-bracket</td>
			<td style="width:109px;"></td>
			<td style="width:135px;"></td>
			<td style="width:419px;"></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:149px;">Telsbar post</td>
			<td style="width:109px;">Unistrut Service Company</td>
			<td style="width:135px;"></td>
			<td style="width:419px;">Secure sensors and sondes in the stream</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Steel wire</td>
			<td style="width:109px;"></td>
			<td style="width:135px;"></td>
			<td style="width:419px;">supend sonde and PT sensor</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Carabiner</td>
			<td style="width:109px;"></td>
			<td style="width:135px;"></td>
			<td style="width:419px;">supend sonde and PT sensor</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Allen wrench</td>
			<td style="width:109px;"></td>
			<td style="width:135px;"></td>
			<td style="width:419px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:149px;">Copper wire mesh</td>
			<td style="width:109px;">Bird B Gone</td>
			<td style="width:135px;"></td>
			<td style="width:419px;">Rodent and bird control copper mesh roll</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:149px;">Adhesive Tape</td>
			<td style="width:109px;">Agri Drain Corporation</td>
			<td style="width:135px;"></td>
			<td style="width:419px;">Tile tape, works in wet and cold weather</td>
		</tr>
	</tbody>
</table>

continuous instream monitoring of nutrients and sediment in agricultural watersheds

Concentrazioni di inquinanti e carichi nei bacini di variano considerevolmente con il tempo e lo spazio. Informazioni accurate e tempestive sulla grandezza di inquinanti delle risorse idriche sono un prerequisito per comprendere i driver dei carichi inquinanti e per prendere acqua informato decisioni di gestione risorse. Il metodo comunemente utilizzato di "afferrare il campionamento" fornisce le concentrazioni degli inquinanti al momento del campionamento (cioè, una concentrazione istantanea) e può sotto- o overpredict le concentrazioni di inquinanti ed i carichi. Monitoraggio continuo di sostanze nutritive e sedimenti, recentemente ha ricevuto più attenzione dovuto gli avanzamenti in informatica, tecnologia e dispositivi di storage di rilevamento. Questo protocollo viene illustrato l'utilizzo di sensori, sonde e strumentazione per il monitoraggio continuo in situ nitrati, ammonio, torbidità, pH, conducibilità, temperatura e ossigeno disciolto (DO) e per calcolare i carichi da due flussi (fosse) in due bacini agricoli. Con la corretta calibrazione, manutenzione e funzionamento di sensori e sonde, dati di acqua di buona qualità possono essere ottenuti superando condizioni difficili come l'accumulo di incrostazioni e residui. Il metodo può anche essere utilizzato nei bacini di varie dimensioni e caratterizzato da terreni agricoli, forestali e/o urbano.

Nella pubblicazione (2017) Aryal e Reba, questo protocollo è stato usato per studiare il trasporto e la trasformazione di sostanze nutritive e dei sedimenti in due piccoli bacini agricoli6. Ulteriori risultati da questo protocollo sono descritti di seguito.
Deflusso acqua qualità relazioni:
La forza di monitoraggio continuo è che gli utenti poss...

Watch this Scientific Journal Video about Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds at JoVE.com

Monitoraggio continuo dei nutrienti e dei sedimenti nei bacini idrografici agricoli | Ambiente | Video

Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds

Con l'avanzamento della tecnologia e l'aumento delle aspettative dell'utente finale, è aumentata la necessità e l'uso di dati di risoluzione temporale superiore per la stima del carico inquinante. Questo protocollo descrive un metodo per il continuo in situ acqua qualità monitoraggio per ottenere maggiore risoluzione temporale dati per acqua informato le decisioni di gestione di risorse.

Instream continuo monitoraggio delle sostanze nutrienti e sedimenti nei bacini agricoli

Pollutant concentrations and loads in watersheds vary considerably with time and space. Accurate and timely information on the magnitude of pollutants in ...

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11.1K Views.  Oak Ridge Institute of Science and Education (ORISE). Con l'avanzamento della tecnologia e l'aumento delle aspettative dell'utente finale, è aumentata la necessità e l'uso di dati di risoluzione temporale superiore per la stima del carico inquinante. Questo protocollo descrive un metodo per il continuo in situ acqua qualità monitoraggio per ottenere maggiore risoluzione temporale dati per acqua informato le decisioni di gestione di risorse.

Video: Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds

Measuring Fluxes of Mineral Nutrients and Toxicants in Plants with Radioactive Tracers

Unidirectional influx and efflux of nutrients and toxicants, and their resultant net fluxes, are central to the nutrition and toxicology of plants. Radioisotope tracing is a major technique used to measure such fluxes, both within plants, and between plants and their environments. Flux data obtained with radiotracer protocols can help elucidate the capacity, mechanism, regulation, and energetics of transport systems for specific mineral nutrients or toxicants, and can provide insight into compartmentation and turnover rates of subcellular mineral and metabolite pools. Here, we describe two major radioisotope protocols used in plant biology: direct influx (DI) and compartmental analysis by tracer efflux (CATE). We focus on flux measurement of potassium (K+) as a nutrient, and ammonia/ammonium (NH3/NH4+) as a toxicant, in intact seedlings of the model species barley (Hordeum vulgare L.). These protocols can be readily adapted to other experimental systems (e.g., different species, excised plant material, and other nutrients/toxicants). Advantages and limitations of these protocols are discussed.

In planta measurement of nutrient and toxicant fluxes is essential to the study of plant nutrition and toxicity. Here, we cover radiotracer protocols for influx and efflux determination in intact plant roots, using potassium (K+) and ammonia/ammonium (NH3/NH4+) fluxes as examples. Advantages and limitations of such techniques are discussed.

Flussi di minerali nutrienti e sostanze tossiche in misura Piante con traccianti radioattivi

Unidirectional influx and efflux of nutrients and toxicants, and their resultant net fluxes, are central to the nutrition and toxicology of plants. ...

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Sediment Core Sectioning and Extraction of Pore Waters under Anoxic Conditions

We demonstrate a method for sectioning sediment cores and extracting pore waters while maintaining oxygen-free conditions. A simple, inexpensive system is built and can be transported to a temporary work space close to field sampling site(s) to facilitate rapid analysis. Cores are extruded into a portable glove bag, where they are sectioned and each 1-3 cm thick section (depending on core diameter) is sealed into 50 ml centrifuge tubes. Pore waters are separated with centrifugation outside of the glove bag and then returned to the glove bag for separation from the sediment. These extracted pore water samples can be analyzed immediately. Immediate analyses of redox sensitive species, such as sulfide, iron speciation, and arsenic speciation indicate that oxidation of pore waters is minimal; some samples show approximately 100% of the reduced species, e.g. 100% Fe(II) with no detectable Fe(III). Both sediment and pore water samples can be preserved to maintain chemical species for further analysis upon return to the laboratory.

A protocol for sectioning sediment cores and extracting pore waters under anoxic conditions in order to permit analysis of redox sensitive species in both solids and fluids is presented.

Sedimenti Nucleo sezionamento ed estrazione di Pore acque sotto anossiche condizioni

We demonstrate a method for sectioning sediment cores and extracting pore waters while maintaining oxygen-free conditions. A simple, inexpensive system is ...

Characterization and Application of Passive Samplers for Monitoring of Pesticides in Water

Five different water passive samplers were calibrated under laboratory conditions for measurement of 124 legacy and current used pesticides. This study provides a protocol for the passive sampler preparation, calibration, extraction method and instrumental analysis. Sampling rates (RS) and passive sampler-water partition coefficients (KPW) were calculated for silicone rubber, polar organic chemical integrative sampler POCIS-A, POCIS-B, SDB-RPS and C18 disk. The uptake of the selected compounds depended on their physicochemical properties, i.e., silicone rubber showed a better uptake for more hydrophobic compounds (log octanol-water partition coefficient (KOW) &#62; 5.3), whereas POCIS-A, POCIS-B and SDB-RPS disk were more suitable for hydrophilic compounds (log KOW &#60; 0.70).

A protocol about the characterization and application of five different passive sampling devices is presented.

Caratterizzazione e applicazione di passivi Campionatori per il monitoraggio dei pesticidi in acqua

Five different water passive samplers were calibrated under laboratory conditions for measurement of 124 legacy and current used pesticides. This study ...

The Benthic Exchange of O2, N2 and Dissolved Nutrients Using Small Core Incubations

The measurement of sediment-water exchange of gases and solutes in aquatic sediments provides data valuable for understanding the role of sediments in nutrient and gas cycles. After cores with intact sediment-water interfaces are collected, they are submerged in incubation tanks and kept under aerobic conditions at in situ temperatures. To initiate a time course of overlying water chemistry, cores are sealed without bubbles using a top cap with a suspended stirrer. Time courses of 4-7 sample points are used to determine the rate of sediment water exchange. Artificial illumination simulates day-time conditions for shallow photosynthetic sediments, and in conjunction with dark incubations can provide net exchanges on a daily basis. The net measurement of N2 is made possible by sampling a time course of dissolved gas concentrations, with high precision mass spectrometric analysis of N2:Ar ratios providing a means to measure N2 concentrations. We have successfully applied this approach to lakes, reservoirs, estuaries, wetlands and storm water ponds, and with care, this approach provides valuable information on biogeochemical balances in aquatic ecosystems.

The Benthic Exchange of O2, N2 and Dissolved Nutrients Using Small Core Incubations

Here, we present small core incubations for the measurement of sediment-water gas and solute exchange. These will provide reliable measurements of sediment-water exchange that assess the role of sediment in influencing biological and biogeochemical processes in aquatic ecosystems.

La Borsa bentonici di O<sub&gt; 2</sub&gt;, N<sub&gt; 2</sub&gt; e nutrienti disciolti Utilizzo piccolo nucleo Incubazioni

The measurement of sediment-water exchange of gases and solutes in aquatic sediments provides data valuable for understanding the role of sediments in ...

Measuring and Mapping Patterns of Soil Erosion and Deposition Related to Soil Carbonate Concentrations Under Agricultural Management

Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes in elevation are related to changes in near-surface soil carbonate (CaCO3) profiles. The objective is to describe a simple conceptual model and detailed protocol for repeatable field and laboratory measurements of these quantities. Here, accurate elevation is measured using a ground-based differential global positioning system (GPS); other data acquisition methods could be applied to the same basic method. Soil samples are collected from prescribed depth intervals and analyzed in the lab using an efficient and precise modified pressure-calcimeter method for quantitative analysis of inorganic carbon concentration. Standard statistical methods are applied to point data, and representative results show significant correlations between changes in soil surface layer CaCO3 and changes in elevation consistent with the conceptual model; CaCO3 generally decreased in depositional areas and increased in erosional areas. Maps are derived from point measurements of elevation and soil CaCO3 to aid analyses. A map of erosional and depositional patterns at the study site, a rain-fed winter wheat field cropped in alternating wheat-fallow strips, shows the interacting effects of water and wind erosion affected by management and topography. Alternative sampling methods and depth intervals are discussed and recommended for future work relating soil erosion and deposition to soil CaCO3.

Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes in elevation are related to changes in near-surface soil carbonates. Repeatable methods for field and laboratory measurements of these quantities and data analysis methods are described here.

Misura e mappatura modelli di erosione e deposizione relazionati al suolo carbonato concentrazioni sotto gestione agricola

Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes ...

Continuous Hydrologic and Water Quality Monitoring of Vernal Ponds

Vernal ponds, also referred to as vernal pools, provide critical ecosystem services and habitat for a variety of threatened and endangered species. However, they are vulnerable parts of the landscapes that are often poorly understood and understudied. Land use and management practices, as well as climate change are thought to be a contribution to the global amphibian decline. However, more research is needed to understand the extent of these impacts. Here, we present methodology for characterizing a vernal pond's morphology and detail a monitoring station that can be used to collect water quantity and quality data over the duration of a vernal pond's hydroperiod. We provide methodology for how to conduct field surveys to characterize the morphology and develop stage-storage curves for a vernal pond. Additionally, we provide methodology for monitoring the water level, temperature, pH, oxidation-reduction potential, dissolved oxygen, and electrical conductivity of water in a vernal pond, as well as monitoring rainfall data. This information can be used to better quantify the ecosystem services that vernal ponds provide and the impacts of anthropogenic activities on their ability to provide these services.

Understanding the ecosystem services and processes provided by vernal ponds and the impacts of anthropogenic activities on their ability to provide these services requires intensive hydrologic monitoring. This sampling protocol using in-situ monitoring equipment was developed to understand the impact of anthropogenic activities on water levels and quality.

Continuo idrologici e monitoraggio della qualità di Vernal stagni di acqua

Vernal ponds, also referred to as vernal pools, provide critical ecosystem services and habitat for a variety of threatened and endangered species. ...

The Hawaii Protocol for Scientific Monitoring of Coffee Berry Borer: a Model for Coffee Agroecosystems Worldwide

Coffee berry borer (CBB) is the most devastating insect pest for coffee crops worldwide. We developed a scientific monitoring protocol that is aimed at capturing and quantifying the dynamics and impact of this invasive insect pest as well as the development of its host plant across a heterogeneous landscape. The cornerstone of this comprehensive monitoring system is timely georeferenced data collection on CBB movement, coffee berry infestation, mortality by the fungus Beauveria bassiana, and coffee plant phenology via a mobile electronic data recording application. This electronic data collection system allows field records to be georeferenced through built-in global positioning systems, and is backed by a network of weather stations and records of farm management practices. Comprehensive monitoring of CBB and host plant dynamics is an essential part of an area-wide project in Hawaii to aggregate landscape-level data for research to improve management practices. Coffee agroecosystems in other parts of the world that experience highly variable environmental and socioeconomic factors will also benefit from implementing this protocol, in that it will drive the development of customized integrated pest management (IPM) to manage CBB populations.

Comprehensive monitoring of coffee berry borer and host plant dynamics is essential for aggregating landscape-level data to improve management of this invasive pest. Here, we present a protocol for scientific monitoring of coffee berry borer movement, infestation, mortality, coffee plant phenology, weather, and farm management via a mobile electronic data recording application.

Il protocollo di Hawaii per monitoraggio scientifico di Coffee Berry Borer: un modello per caffè agroecosistemi in tutto il mondo

Coffee berry borer (CBB) is the most devastating insect pest for coffee crops worldwide. We developed a scientific monitoring protocol that is aimed at ...

The Plant Infection Test: Spray and Wound-Mediated Inoculation with the Plant Pathogen Magnaporthe Grisea

Plants possess a powerful system to defend themselves against potential threats by pathogenic fungi. For agriculturally important plants, however, current measures to combat such pathogens have proved too conservative and, thus, not sufficiently effective, and they can potentially pose environmental risks. Therefore, it is extremely necessary to identify host-resistance factors to assist in controlling plant diseases naturally through the identification of resistant germplasm, the isolation and characterization of resistance genes, and the molecular breeding of resistant cultivars. In this regard, there is need to establish an accurate, rapid, and large-scale inoculation method to breed and develop plant resistance genes. The rice blast fungal pathogen Magnaporthe grisea causes severe disease symptoms and yield losses. Recently, M. grisea has emerged as a model organism for studying the mechanisms of plant-fungal pathogen interactions. Hence, we report the development of a plant virulence test method that is specific for M. grisea. This method provides for both spray inoculation with a conidial suspension and wounding inoculation with mycelium cubes or droplets of conidial suspension. The key step of the wounding inoculation method for detached rice leaves is to make wounds on plant leaves, which avoids any interference caused by host penetration resistance. This spray/wounding protocol contributes to the rapid, accurate, and large-scale screening of the pathotypes of M. grisea isolates. This integrated and systematic plant infection method will serve as an excellent starting point for gaining a broad perspective of issues in plant pathology.

The Plant Infection Test: Spray and Wound-Mediated Inoculation with the Plant Pathogen Magnaporthe Grisea

Here, we present a protocol to test plant virulence with the plant pathogen Magnaporthe grisea. This report will contribute to the large-scale screening of the pathotypes of fungi isolates and serve as an excellent starting point for understanding the resistant mechanisms of plants during molecular breeding.

La prova di infezione di pianta: Spray e ferita-mediata di inoculazione con la pianta patogeno Magnaporthe Grisea

Plants possess a powerful system to defend themselves against potential threats by pathogenic fungi. For agriculturally important plants, however, current ...

Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors

Denitrification is the primary biogeochemical process removing reactive nitrogen from the biosphere. The quantitative evaluation of this process has become particularly relevant for assessing the anthropogenic-altered global nitrogen cycle and the emission of greenhouse gases (i.e., N2O). Several methods are available for measuring denitrification, but none of them are completely satisfactory. Problems with existing methods include their insufficient sensitivity, and the need to modify the substrate levels or alter the physical configuration of the process using disturbed samples.This work describes a method for estimating sediment denitrification rates that combines coring, acetylene inhibition, and microsensor measurements of the accumulated N2O. The main advantages of this method are a low disturbance of the sediment structure and the collection of a continuous record of N2O accumulation; these enable estimates of reliable denitrification rates with minimum values up to 0.4-1 &#181;mol N2O m-2 h-1. The ability to manipulate key factors is an additional advantage for obtaining experimental insights. The protocol describes procedures for collecting the cores, calibrating the sensors, performing the acetylene inhibition, measuring the N2O accumulation, and calculating the denitrification rate. The method is appropriate for estimating denitrification rates in any aquatic system with retrievable sediment cores. If the N2O concentration is above the detection limit of the sensor, the acetylene inhibition step can be omitted to estimate the N2O emission instead of denitrification. We show how to estimate both actual and potential denitrification rates by increasing nitrate availability as well as the temperature dependence of the process. We illustrate the procedure using mountain lake sediments and discuss the advantages and weaknesses of the technique compared to other methods. This method can be modified for particular purposes; for instance, it can be combined with 15N tracers to assess nitrification and denitrification or field in situ measurements of denitrification rates.

Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors

This method estimates sediment denitrification rates in sediment cores using the acetylene inhibition technique and microsensor measurements of the accumulated N2O. The protocol describes procedures for collecting the cores, calibrating the sensors, performing the acetylene inhibition, measuring the N2O accumulation, and calculating the denitrification rate.

Stimare i tassi di denitrificazione sedimento utilizzando core e N2O microsensori

Denitrification is the primary biogeochemical process removing reactive nitrogen from the biosphere. The quantitative evaluation of this process has ...

Two-Dimensional Visualization and Quantification of Labile, Inorganic Plant Nutrients and Contaminants in Soil

We describe a method for two-dimensional (2D) visualization and quantification of the distribution of labile (i.e., reversibly adsorbed) inorganic nutrient (e.g., P, Fe, Mn) and contaminant (e.g., As, Cd, Pb) solute species in the soil adjacent to plant roots (the &#8216;rhizosphere&#8217;) at sub-millimeter (~100 &#181;m) spatial resolution. The method combines sink-based solute sampling by the diffusive gradients in thin films (DGT) technique with spatially resolved chemical analysis by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The DGT technique is based on thin hydrogels with homogeneously distributed analyte-selective binding phases. The variety of available binding phases allows for the preparation of different DGT gel types following simple gel fabrication procedures. For DGT gel deployment in the rhizosphere, plants are grown in flat, transparent growth containers (rhizotrons), which enable minimal invasive access to a soil-grown root system. After a pre-growth period, DGT gels are applied to selected regions of interest for in situ solute sampling in the rhizosphere. Afterwards, DGT gels are retrieved and prepared for subsequent chemical analysis of the bound solutes using LA-ICP-MS line-scan imaging. Application of internal normalization using 13C and external calibration using matrix-matched gel standards further allows for the quantification of the 2D solute fluxes. This method is unique in its capability to generate quantitative, sub-mm scale 2D images of multi-element solute fluxes in soil-plant environments, exceeding the achievable spatial resolution of other methods for measuring solute gradients in the rhizosphere substantially. We present the application and evaluation of the method for imaging multiple cationic and anionic solute species in the rhizosphere of terrestrial plants and highlight the possibility of combining this method with complementary solute imaging techniques.

This protocol presents a workflow for sub-mm 2D visualization of multiple labile inorganic nutrient and contaminant solute species using diffusive gradients in thin films (DGT) combined with mass spectrometry imaging. Solute sampling and high-resolution chemical analysis are described in detail for quantitative mapping of solutes in the rhizosphere of terrestrial plants.