The authors thank Drs. Bobby J. Presley, Robert Tayloy, Paul Boothe, Mr. Bryan Brattin, and Mr. Mike Metcalf for their assistance during the laborious field sampling and lab work for the practical development and application of "clean techniques".

1.サンプラーの準備<ol><li>サンプラー<ol><li>サンプラーの集合<ol><li> 1.5メートル耐薬品性シリコーン圧送管（OD 0.635センチメートル）に4メートルの長いフッ化エチレンプロピレン（FEP）チューブ（ID 0.635センチメートル、OD 0.95センチメートルまたは類似）を接続します。 </li><li>ポンピングチューブにポリプロピレンYコネクタを挿入し、他の一つの出口、及び（20 cmの圧送管によって）0.45μmのカプセルフィルターに50 cmのポンピングチューブを接続します。 </li><li>それらが清掃された後、クリーンルーム（ベンチ）にチューブを組み立てます（下記参照）、およびポリエチレン袋の2層に集合体を格納します。 </li></ol></li><li>サンプラークリーニング<ol><li>ラボ用洗剤液でチューブセット（蠕動ポンプの上に1.5メートルのポンプチューブを取り付けることにより）を記入し、24時間のためにそれを浸します。 10％（v / v）の塩酸（試薬グレード）とそれを記入し、48時間浸し、その後、脱イオン水でセットチューブを洗い流します。 </li><li>徹底的に脱イオンワットで設定したチューブをフラッシュ数回ATER、プラスチック袋に集合体を格納します。 24時間50％（v / v）のHNO 3（試薬グレード）溶液中でそれらを浸すことによって、Yコネクタと短い揚水管を清掃してください。 </li></ol></li><li>カプセルフィルター<ol><li>最初の脱イオン水で48時間の浸漬工程のため、その後、10％（v / v）のHCl溶液を、それらをフラッシュすることによって、カプセルフィルターを清掃してください。 </li><li>酸浸漬した後、脱イオン水でフィルターをフラッシュし、酸を中和するために、各フィルターに21％（重量）NH 4 OH（サブゆで）溶液1mlを追加します。 </li><li>ポリエチレンジッパー付きの袋に30-cmのクリーンポンプ入口と出口を接続管、および店舗のループで個々のフィルタをシール。 </li></ol></li></ol></li><li>サンプル容器<ol><li>ポリエチレン（PE、1,000ミリリットル）とFEP（500ミリリットルと千ミリリットル）微量金属決意用容器のためのボトルを使用してください。 <ol><li> （1％）第一の界面活性剤でそれらを浸すことによってボトルをきれいにし、その後、50％（v / v）のHNO 3（試薬グレード）、および24、48および24時間、10％（v / v）の塩酸（試薬グレード）の溶液を、それぞれ、および2つの浸漬工程の間に脱イオン水でボトルをすすぎます。 </li><li>最終塩酸浸漬した後、完全に脱イオン水（DIW）でボトルをすすぎ、クリーンルームやクラス100クリーンベンチ内（密封されたキャップ付き）ボトルを乾燥させます。 </li><li>シールは、輸送のためのポリエチレン袋にポリエチレンジッパー付きの袋にペットボトルや二重袋にそれらを掃除しました。 </li></ol></li><li>溶存有機炭素（DOC）決意のためにきれいなガラスびん<ol><li> 48時間、10％のHClで、溶存有機炭素（DOC）の分析のために、琥珀色ホウケイ酸ガラスボトル（40 ml）に浸し。脱イオン水で洗浄したガラスボトルをすすぎ、そして使用前に2時間480℃でそれらを燃焼。輸送のためのジッパー付きポリエチレン袋に個別のボトルを密封します。 </li></ol></li></ol></li></ol> 2.サンプリング<ol><li>水サンプル採取<ol><li> UPOn個のサンプリングサイトに到着、外袋のマークサンプル識別番号と、元の袋にボトルを保持します。 </li><li>川の土手で、またはボートに乗って、1人はサンプラーで袋を開けていると3メートルのポリプロピレンポール（洗浄）に4メートルのFEPチューブを取り付けます。できるだけ銀行からポールを伸ばし、30cm程度のポンプがオンになっている前に、河川の流水の表面下のFEPチューブの入口を保ちます。 </li><li>別の人は、蠕動ポンプ（内蔵バッテリ付きサンプリングポンプ）のポンプヘッドにポンプチューブを取り付ける必要があります。ポンプを起動し、水（下流側）総サンプラー容積の少なくとも3倍のドレイン。パウダーフリーの手袋を着用して、サンプル瓶を充填開始するボトルとキャップの袋を開きます。 <ol><li>別の人が利用可能な場合あるいは、第三者がインナーバッグやサンプルのキャップを開け、aとbに試料を排出するサンプリングチューブを保持する担当してきましたottle。 </li></ol></li><li>フィールド内の導電率、温度およびpHの測定のための125ミリリットルのペットボトルでフィルタリングされていないサンプルを収集します。 </li><li> （1（フィルタなしコンセントを介して）最初の（500-mlまたは粒子状のサンプル収集のための千ミリリットル）フィルタ処理されていないサンプルを収集した後、ろ過水のサンプルを収集するためにカプセルフィルターを通過する水を強制的にプラスチック製のクランプでコンセントを閉じます溶解した微量金属決意用-L）。 </li><li> DOCおよびEDTA測定のための40ミリリットルのアンバーガラスびんに（フィルター付きコンセントを介して）、濾過したサンプルを収集します。 </li><li> 1,000ミリリットル/分に近い500ml /分の流速で水サンプルを収集します。圧力が（フィルタ」仕様に応じて）構築を開始したときにカプセルフィルターを交換してください。サンプルの種類ごとに、品質管理アリコートとして機能するように選択された位置で、余分なサンプルだけでなく、フィールドブランクを収集します。 </li><li>ドライアイスと保存されている私に40ミリリットルのガラスボトルを置きます氷の胸、アイスチェスト中のポリエチレンボトルのn。 </li></ol></li><li>浮遊粒子状物質の集合（SPM） <ol><li>プラスチック製濾過漏斗および容器を用いて、真空濾過により0.4μmのポリカーボネート（PC）膜フィルター（酸洗浄し、予め秤量した）にSPMを集めます。 </li><li> SPM濃度を生じ、粒状微量金属決意するための粒子サンプルを提供するために、実験室で乾燥した膜フィルタを凍結。 </li></ol></li></ol> 3.サンプルの前処理（溶存微量金属） <ol><li>溶解した微量金属の決意について、サンプル瓶に2mlの濃サブ煮HNO 3（1-Lあたりのサンプル）を追加します。 FEPボトルに溶解した微量金属試料（酸性化）を転送します。あるいは、サンプルは、FEPボトルに直接回収することができます。 24時間（8〜15ワットのUVランプ）用のFEPボトル内のサンプルをUV-照射。 </li></ol>微量金属分析のための4.前濃縮および治療<ol><li&gt;の前濃縮樹脂<ol><li>小さ ​​な（10-30 mLの容量）のプラスチックカップに陽イオン交換樹脂を2g秤量し、カップに2 N HNO 3溶液を少量加えます。 10ミリリットルの容量クロマトグラフィーカラムに樹脂を注ぎます。二回（サブゆで）5-mlの2 N HNO 3でカラムを洗浄することにより樹脂を清掃し、かつ高純度の水（HPW）で3回すすいでください。 </li><li> NH 4 +型に樹脂を変換するために、カラムに1 M NH 4 OH（サブゆで）の10ミリリットルを追加します。 </li></ol></li><li>緩衝液（1 M酢酸アンモニウム） <ol><li> HPWの約800ミリリットル中（サブゆで）氷酢酸の57ミリリットルを追加します。 〜（サブ煮21％）水酸化アンモニウムの60ミリリットルを加え、酢酸で混ぜます。 5.5への最終pHと千ミリリットルへの最終的な音量を調整します。 </li></ol></li><li>予備濃縮手順（微量金属を溶解しました） <ol><li> 1 MアンモニアACET 30mlのを添加することによって5.5±0.3に酸性化し、UV照射サンプルのpHを調整します試料に緩衝液と一部（〜2.8ミリリットル）NH 4 OH（サブゆで）を食べました。 </li><li> 〜30センチメートル陽イオン交換樹脂（4.1節）を充填したカラム上にサンプル瓶を置き、~60センチFEPチューブとクロマトグラフィーキャップとコネクタ（メスルアー）により試料瓶と前濃縮カラムを接続します。 </li><li>列の上に接続された2方コックを使用して3〜5ミリリットル/分の流量を制御します。サンプルは前濃縮カラムを通過することを許可します。サンプルがカラムを通過した後、カラムからのチューブとキャップを外してください。 </li><li> 2×5 mlのHPWと1 M酢酸アンモニウム（pHは5.5）の4×5ミリリットル、および他の微量金属からの主要な陽イオンを分離するためのHPWの2×5ミリリットルの列を扱います。 </li><li>ちょうど列の下に30 mlの酸洗浄PE瓶を置き、PEボトルに7×1-mlの2 N HNO 3（サブゆで）でカラムを洗浄します。 </li><li>重量aを取得することにより、2 N HNO 3の流出物（〜8.0ミリリットル）の容積を決定しますND 2 N HNO 3流出液の比重。 </li></ol></li><li>浮遊粒子状物質の消化<ol><li> SPMサンプルとドライPCフィルターを凍結乾燥後、それらの重量を量ります。予め計量したペルフルオロアルカン（PFA）船舶（60-mlの容量）に、フィルタと、SPMのサンプルを配置し、容器に濃HNO 3の3ミリリットルを追加します。 </li><li> 2.5キロメートルの一定のトルクに血管を締めて、12時間130℃で、従来のオーブンで消化しました。冷却後、血管を開き、容器にHFの2ミリリットルを追加します。 </li><li> 2.5キロメートルの一定のトルクに血管を締めて、12時間130℃で、従来のオーブンで消化しました。冷却後、血管を開き、容器に4.5％ホウ酸溶液の16ミリリットルを追加します。 </li><li> 2.5キロメートルの一定のトルクに血管を締めて、12時間130℃で、従来のオーブンでダイジェスト。各容器を計量し、それぞれの消化液の比重を決定します最終ダイジェスト体積を得ました。 </li><li>各フィルタ上のSPMの最終体積と重量（フィルタ上に試料の重量で割った最終ダイジェストボリューム）からダイジェスト用の希釈係数を計算します。 </li></ol></li></ol> 5.サンプルの分析<ol><li>微量金属<ol><li>事前に濃縮サンプルとフレーム原子吸光分析、黒鉛炉原子吸光分析法を用いて、微粒子からの溶液に溶解し、および/または誘導結合プラズマ中に微量金属（カドミウム、CoとCuの、鉄、マンガン、ニッケル、鉛、およびZn）濃度を決定質量分析計。 </li><li>誘導結合プラズマ発光分光分析により、前浮遊粒子状物質の予備濃縮および消化に描かれたサブサンプル中の主要イオン濃度といくつかの微量金属を、決定します。 </li></ol></li><li>補助パラメータ<ol><li>ポータブルデバイスを使用して、フィールド内の試料温度、pH、塩分濃度と導電率を決定します。 </li><li>決定溶解または赤外分光法21による二酸化炭素の検出と湿式酸化に基づいて、全有機炭素分析によりganic炭素（DOC）濃度、。確立された手順22,23以下（SPD-M10AV Diodearray検出器付き）高速液体クロマトグラフィーによる総EDTAの濃度を決定します。 </li></ol></li></ol>

<ol>
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T., 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+comparison+of+methods+for+the+measurement+of+dissolved+organic+carbon+in+natural+waters.">A comparison of methods for the measurement of dissolved organic carbon in natural waters.</a> Marine Chemistry. 54, 85-96 (1996).</li><li>Nowack, B., Kari, F., Hilger, S. U., Sigg, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+dissolved+and+adsorbed+EDTA+species+in+water+and+sediments+by+HPLC.">Determination of dissolved and adsorbed EDTA species in water and sediments by HPLC.</a> Analytical Chemistry. 68 (3), 561-566 (1996).</li><li>Bergers, P. J. M., de Groot, A. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+analysis+of+EDTA+in+water+by+HPLC.">The analysis of EDTA in water by HPLC.</a> Water Research. 28 (3), 639-642 (1994).</li></ol>

The authors have no conflict of interests to disclose.

天然水で信頼性の高い微量金属のデータを取得する汚染を低減することを目指して、サンプル収集、処理、前処理、および分析中に強調したよう細心の注意が必要です。濃度は、以前に報告されたものより数桁低いことができることを見出し、最後の二十年で「クリーン技術」を用いて得られた天然水中の金属濃度をトレースします。微量金属のレベルを正確にヒトおよび高等生物に有害な?...

一般的に天然水に対して得られたいくつかの微量金属の結果は、サンプル収集、トリートメントと決意1,2の間に適用される不十分な技術に起因するアーチファクトのため不正確であることが認識されてきました。溶解した微量金属の真の濃度は、（地表水3におけるnM範囲にサブnM単位）以前に発表された値よりも2桁低いまでになりました。同じ状況が改善されたサンプリングと分析方法が導入されているとして海洋水域で受け入れられた溶存微量金属濃度は過去40年ほどかけて桁違いに減少しており、海洋化学で発見されました。努力は、微量金属の分析4-8のすべての段階を通して微量金属汚染の低減又は排除を目的と「クリーン技術」の開発とデータ品質を改善する試みがなされています。周囲における微量金属濃度の決意するためレベルは、予備濃縮がしばしば要求されます。イオン交換技術8-12は、一般的に効率的な予備濃縮のために適用されています。 汚染は、容器の壁、容器の洗浄、サンプラー、サンプルの取り扱いや保管、およびサンプルの保存と分析7,13から生じ得ます。さらに最近行っきれいな方法を用いて、全ての研究は、天然水中の微量金属の濃度は、一般的によく日常的な方法7の検出限界未満であることを示しています。その水質モニタリングが15を投影するために1990年代初めの容疑者の微量金属データの認識ので、クリーンな方法は、米国EPA（環境保護庁）に組み込まれている微量金属の決意14と米国地質調査所のためのガイドラインは、クリーンな方法を採用しています。微量金属の研究のためのクリーンな方法は、しっかりと正確なデータ・ベースを作成するために、すべてのプロジェクトで採用される必要があります。 <pクラス原則として= &quot;jove_content&quot;&gt;、微量金属決意に使用する水のサンプルは、適切なサンプリング特定の材料のギアや組成物を収集、保存し、機器分析を進める前に、適当な容器および装置を用いて、適切に扱われるべきです。浮遊粒子状物質（SPM）は、サンプル保管期間中に変化を受け、水の組成を変化させることができるので、水試料からのSPMの迅速な分離は、水環境中の微量金属の研究のための一般的な方法です。天然水中の溶存微量金属濃度の決意ため、濾過が必要であり、インライン濾過技術が適切かつ効率的です。 そのような表面とグラウンド水域などの水生環境における微量金属の分布と挙動が（ 例えば 、風化）自然と人為的（ 例えば 、廃水流出物）の要因、ならびに再など他の環境条件によって影響を受けることができますgional地質学、形態、土地利用や植生、気候16-19。これは、その後、浮遊粒子状物質（SPM）、溶存有機炭素（DOC）、人為的なリガンド（ 例えば 、エチレンジアミン四酢酸、EDTA）、塩、酸化還元電位およびpH 17-20の濃度などの物理化学的パラメータの違いにつながることができます。したがって、正確な、関連する微量金属の研究は、適切な微量金属分析のための試料の採取ならびにための関連要因とパラメータの決意を必要とします。

<table><tbody><tr><td>Nitric Acid</td><td>Seastar Chemicals</td><td></td><td>Baseline grade</td></tr><tr><td>Ammonium hydroxide</td><td>Seastar Chemicals</td><td></td><td>Baseline grade</td></tr><tr><td>Acetic Acid</td><td>Seastar Chemicals</td><td></td><td>Baseline grade</td></tr><tr><td>Nitric Acid</td><td>J. T. Baker</td><td>9601-05</td><td>Reagent grade</td></tr><tr><td>Hydrochloric acid</td><td>J. T. Baker</td><td>9530-33</td><td>Reagent grade</td></tr><tr><td>Chromatographic columns</td><td>Bio-Rad</td><td>7311550&amp;nbsp;</td><td>Poly-Prep</td></tr><tr><td>Column stack caps</td><td>Bio-Rad</td><td>7311555</td><td></td></tr><tr><td>Cap connectors (female Luers)</td><td>Bio-Rad</td><td>7318223</td><td></td></tr><tr><td>2-way stopcocks</td><td>Bio-Rad</td><td>7328102</td><td></td></tr><tr><td>Cation exchange resin</td><td>Bio-Rad</td><td>1422832&amp;nbsp;</td><td>Chelex-100</td></tr><tr><td>Portable sampler (sampling pump)</td><td>Cole Palmer</td><td>EW-07571-00</td><td></td></tr><tr><td>FEP tube</td><td>Cole Palmer</td><td>EW-06450-07</td><td>6.4 mm I.D., 9.5 mm O.D.</td></tr><tr><td>Pumping tube</td><td>Cole Palmer</td><td>EW-06424-24</td><td>6.4 mm I.D. C-Flex</td></tr><tr><td>Capsule filter (0.4 mm)</td><td>Fisher Scientific</td><td>WP4HY410F0</td><td>polypropylene casing</td></tr><tr><td>1 L low density polyethylene bottle</td><td>NALGE NUNC INTERNATIONAL</td><td>312088-0032</td><td></td></tr><tr><td>1 L (or 500 ml) FEP bottle</td><td>NALGE NUNC INTERNATIONAL</td><td>381600-0032</td><td></td></tr></tbody></table>

clean sampling and analysis of river and estuarine waters for trace metal studies

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination control. Developments of some techniques aiming to reduce trace metal contamination in the last couple of decades have resulted in concentrations reported now being orders of magnitude lower than those in the past. These low concentrations often necessitate preconcentration of water samples prior to instrumental analysis of samples. Since contamination can appear in all phases of trace metal analyses, including sample collection (and during preparation of sampling containers), storage and handling, pretreatments, and instrumental analysis, specific care needs to be taken in order to reduce contamination levels at all steps. The effort to develop and utilize "clean techniques" in trace metal studies allows scientists to investigate trace metal distributions and chemical and biological behavior in greater details. This advancement also provides the required accuracy and precision of trace metal data allowing for environmental conditions to be related to trace metal concentrations in aquatic environments.
This protocol that is presented here details needed materials for sample preparation, sample collection, sample pretreatment including preconcentration, and instrumental analysis. By reducing contamination throughout all phases mentioned above for trace metal analysis, much lower detection limits and thus accuracy can be achieved. The effectiveness of "clean techniques" is further demonstrated using low field blanks and good recoveries for standard reference material. The data quality that can be obtained thus enables the assessment of trace metal distributions and their relationships to environmental parameters.

「クリーン技術」の開発および使用には、現在よく、周囲の海域で正確な微量金属濃度を得るために、水試料中の微量金属の前濃縮が一般的であることが認識されます。天然水中の微量金属のための最も水質基準が低いμgの/ Lの範囲であるが、検出下限は、水生環境における周囲の濃度で微量金属上の地球化学的および生物学的効果を調査するために必要とされてい...

Watch this Scientific Journal Video about Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies at JoVE.com

Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies

Special care using "clean techniques" is required to properly collect and process water samples for trace metal studies in aquatic environments. A protocol for sampling, processing, and analytical procedures with the aim of obtaining reliable environmental monitoring data and results with high sensitivity for detailed trace metal studies is presented.

きれいなサンプリングと微量金属の研究のために川や河口ウォーターズの分析

Most of the trace metal concentrations in ambient waters obtained a few decades ago have been considered unreliable owing to the lack of contamination ...

clean-sampling-analysis-river-estuarine-waters-for-trace-metal

Research

JoVE Journal

Environment

11.3K ビュー.  National Sun Yat-sen University. Special care using "clean techniques" is required to properly collect and process water samples for trace metal studies in aquatic environments. A protocol for sampling, processing, and analytical procedures with the aim of obtaining reliable environmental monitoring data and results with high sensitivity for detailed trace metal studies is presented.

ビデオ: Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae

Increasing demand for renewable fuels has researchers investigating the feasibility of alternative feedstocks, such as microalgae. Inherent advantages include high potential yield, use of non-arable land and integration with waste streams. The nutrient requirements of a large-scale microalgae production system will require the coupling of cultivation systems with industrial waste resources, such as carbon dioxide from flue gas and nutrients from wastewater. Inorganic contaminants present in these wastes can potentially lead to bioaccumulation in microalgal biomass negatively impact productivity and limiting end use. This study focuses on the experimental evaluation of the impact and the fate of 14 inorganic contaminants (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Se, Sn, V and Zn) on Nannochloropsis salina growth. Microalgae were cultivated in photobioreactors illuminated at 984 &#181;mol m-2 sec-1 and maintained at pH 7 in a growth media polluted with inorganic contaminants at levels expected based on the composition found in commercial coal flue gas systems. Contaminants present in the biomass and the medium at the end of a 7 day growth period were analytically quantified through cold vapor atomic absorption spectrometry for Hg and through inductively coupled plasma mass spectrometry for As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sb, Se, Sn, V and Zn. Results show N. salina is a sensitive strain to the multi-metal environment with a statistical decrease in biomass yieldwith the introduction of these contaminants. The techniques presented here are adequate for quantifying algal growth and determining the fate of inorganic contaminants.

Integration of microalgal cultivation with industrial flue gas will ultimately introduce heavy metals and other inorganic compounds into the growth media. This study presents a procedure used to determine the end fate and impact of heavy metals and inorganic contaminants on the growth of Nannochloropsis salina grown in photobioreactors.

重金属や微細藻類の生産性に関するその他の無機汚染物質の定量

Increasing demand for renewable fuels has researchers investigating the feasibility of alternative feedstocks, such as microalgae. Inherent advantages ...

環境学

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.

無酸素状態下での堆積物コアセクショニングと間隙水の抽出

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

Watershed Planning within a Quantitative Scenario Analysis Framework

There is a critical need for tools and methodologies capable of managing aquatic systems within heavily impacted watersheds. Current efforts often fall short as a result of an inability to quantify and predict complex cumulative effects of current and future land use scenarios at relevant spatial scales. The goal of this manuscript is to provide methods for conducting a targeted watershed assessment that enables resource managers to produce landscape-based cumulative effects models for use within a scenario analysis management framework. Sites are first selected for inclusion within the watershed assessment by identifying sites that fall along independent gradients and combinations of known stressors. Field and laboratory techniques are then used to obtain data on the physical, chemical, and biological effects of multiple land use activities. Multiple linear regression analysis is then used to produce landscape-based cumulative effects models for predicting aquatic conditions. Lastly, methods for incorporating cumulative effects models within a scenario analysis framework for guiding management and regulatory decisions (e.g., permitting and mitigation) within actively developing watersheds are discussed and demonstrated for 2 sub-watersheds within the mountaintop mining region of central Appalachia. The watershed assessment and management approach provided herein enables resource managers to facilitate economic and development activity while protecting aquatic resources and producing opportunity for net ecological benefits through targeted remediation.

There is a critical need for tools and methodologies capable of managing aquatic systems in the face of uncertain future conditions. We provide methods for conducting a targeted watershed assessment that enables resource managers to produce landscape-based cumulative effects models for use within a scenario analysis management framework.

定量的シナリオ分析フレームワーク内の流域計画

There is a critical need for tools and methodologies capable of managing aquatic systems within heavily impacted watersheds. Current efforts often fall ...

Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds

Pollutant concentrations and loads in watersheds vary considerably with time and space. Accurate and timely information on the magnitude of pollutants in water resources is a prerequisite for understanding the drivers of the pollutant loads and for making informed water resource management decisions. The commonly used &#34;grab sampling&#34; method provides the concentrations of pollutants at the time of sampling (i.e., a snapshot concentration) and may under- or overpredict the pollutant concentrations and loads. Continuous monitoring of nutrients and sediment has recently received more attention due to advances in computing, sensing technology, and storage devices. This protocol demonstrates the use of sensors, sondes, and instrumentation to continuously monitor in situ nitrate, ammonium, turbidity, pH, conductivity, temperature, and dissolved oxygen (DO) and to calculate the loads from two streams (ditches) in two agricultural watersheds. With the proper calibration, maintenance, and operation of sensors and sondes, good water quality data can be obtained by overcoming challenging conditions such as fouling and debris buildup. The method can also be used in watersheds of various sizes and characterized by agricultural, forested, and/or urban land.

With the advancement of technology and the rise in end-user expectations, the need and use of higher temporal resolution data for pollutant load estimation has increased. This protocol describes a method for continuous in situ water quality monitoring to obtain higher temporal resolution data for informed water resource management decisions.

連続インストリームの栄養素と農業生態系流域における堆積物の監視

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

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles

The distributions of many trace elements in the ocean are strongly associated with the growth, death, and re-mineralization of marine plankton and those of suspended/sinking particles. Here, we present an all plastic (Polypropylene and Polycarbonate), multi-layer filtration system for collection of suspended particulate matter (SPM) at sea. This ultra-clean sampling device has been designed and developed specifically for trace element studies. Meticulous selection of all non-metallic materials and utilization of an in-line flow-through procedure minimizes any possible metal contamination during sampling. This system has been successfully tested and tweaked for determining trace metals (e.g., Fe, Al, Mn, Cd, Cu, Ni) on particles of varying size in coastal and open ocean waters. Results from the South China Sea at the South East Asia Time-Series (SEATS) station indicate that diurnal variations and spatial distribution of plankton in the euphotic zone can be easily resolved and recognized. Chemical analysis of size-fractionated particles in surface waters of the Taiwan Strait suggests that the larger particles (&#62;153 &#181;m) were mostly biologically derived, while the smaller particles (10 - 63 &#181;m) were mostly composed of inorganic matter. Apart from Cd, the concentrations of metals (Fe, Al, Mn, Cu, Ni) decreased with increasing size.

Plankton and suspended particles play a major role in the biogeochemical cycles in the ocean. Here, we provide an ultra-clean, low stress method for the collection of various sizes of particles and plankton at sea with the capability of handling large volumes of seawater.

サイズ分画した海洋プランクトンや懸濁粒子を収集するための超きれいな積層装置

The distributions of many trace elements in the ocean are strongly associated with the growth, death, and re-mineralization of marine plankton and those ...

Seawater Sampling and Collection

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass concentration, nucleic acid purification, cell abundance, nutrient and trace gas analyses. For today's demonstration samples were collected from the deck of the HMS John Strickland operating in Saanich Inlet. An A-frame derrick, with a multi-purpose winch and cable system, is used in combination with Niskin or Go-Flo water sampling bottles. Conductivity, Temperature, and Depth (CTD) sensors are also used to sample the underlying water mass. To minimize outgassing, trace gas samples are collected first.  Then, nutrients, water chemistry, and cell counts are determined. Finally, waters are collected for biomass filtration. The set-up and collection time for a single cast is ~1.5 hours at a maximum depth of 215 meters. Therefore, a total of 6 hours is generally needed to complete the collection series described here.

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass concentration, nucleic acid purification, cell abundance, nutrient and trace gas analyses.

海水のサンプリングとコレクション

This video documents methods for collecting coastal marine water samples and processing them for various downstream applications including biomass ...

生物学

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.

土壌中の不安定な植物、無機植物の栄養素および汚染物質の二次元可視化と定量化

We describe a method for two-dimensional (2D) visualization and quantification of the distribution of labile (i.e., reversibly adsorbed) inorganic ...

Dissolved Solute Sampling Across an Oxic-Anoxic Soil-Water Interface Using Microdialysis Profilers

Biogeochemical processes shift rapidly in both spatial (millimeter scale) and temporal (hour scale to day scale) dimensions at the oxic-anoxic interface in response to disturbances. Deciphering the rapid biogeochemical changes requires in situ, minimally invasive tools with high spatial and temporal sampling resolution. However, the available passive sampling devices are not very useful in many cases either due to their disposable nature or the complexity and extensive workload for sample preparation.
To address this problem, a microdialysis profiler with 33 individual polyethersulfone nanomembrane tubes (semipermeable, &#60;20 nm pore size) integrated into the one-dimensional skeleton (60 mm) was established to iteratively sample the dissolved compounds in porewater across the soil-water interface at a high resolution of 1.8 mm (outer diameter plus one spacing, i.e., 0.1 mm between probes). The sampling mechanism is based on the principle of concentration gradient diffusion. The automatic loading of degassed water allows minimal disturbance to the chemical species across the oxic-anoxic interface.
This paper describes the procedures of device setup and continuous porewater sampling across the soil-water interface on a daily basis. Concentration-depth profiles were selectively measured before (on Day 6) and after (on Day 7) disturbances induced by irrigation. The results showed that concentration-depth profiles were undergoing rapid changes, especially for redox-sensitive elements (i.e., iron and arsenic). These protocols can help investigate the biogeochemical responses across the soil-water interface under various disturbances caused by physical, chemical, and biological factors. The paper thoroughly discusses the advantages and disadvantages of this method for potential use in the environmental sciences.

A microdialysis profiler is described to sample dissolved porewater solutes across an oxic-anoxic soil-water interface in situ with minimal disturbance. This device is designed to capture rapid changes in concentration-depth profiles induced by disturbances at the soil-water interface and beyond.

マイクロ透析プロファイラーを用いた酸素-無酸素土壌-水界面での溶存溶質サンプリング

Biogeochemical processes shift rapidly in both spatial (millimeter scale) and temporal (hour scale to day scale) dimensions at the oxic-anoxic interface ...

Hellgrammite as a Non-Conventional Biomonitor for Surface Water and Environmental Health Assessment

The larvae of dobsonflies from the genus Corydalus, commonly known as Hellgrammites, are characterized by their notable size, extensive range of occurrence, and extended period of immaturity, which can last up to one year. Hellgrammites are clearly known to exhibit sensitivity to pollution and habitat structure impacts. Given these unique features, using Corydalus texanus larvae is highly suitable as reliable biomonitoring agents to assess the ecological integrity of aquatic ecosystems. This protocol aims to provide the necessary tools for C. texanus assessment and demonstrate their efficacy through a case study. Research findings have practical implications, indicating that C. texanus larvae exhibit early-warning responses to mining pollution, bioaccumulating high amounts of heavy metals such as Zn, Fe, and Al. The presence or absence of C. texanus populations may serve as a helpful indicator for identifying potential issues related to ecosystem health. The unconventional approach has shown early warnings of pollution in mining-impacted sites, highlighting the need for timely action to protect the environment. Given their unique traits, the use of C. texanus larvae is highly suggested as a reliable non-conventional bioindicator.

This protocol describes the use of biomarkers for the early detection of deleterious impacts in aquatic ecosystems. The biomarkers are closely related to sentinel traits, and their changes aid in detecting early-warning damages.

The larvae of dobsonflies from the genus Corydalus, commonly known as Hellgrammites, are characterized by their notable size, extensive range of ...

Fabrication of a Dipole-assisted Solid Phase Extraction Microchip for Trace Metal Analysis in Water Samples

This paper describes a fabrication protocol for a dipole-assisted solid phase extraction (SPE) microchip available for trace metal analysis in water samples. A brief overview of the evolution of chip-based SPE techniques is provided. This is followed by an introduction to specific polymeric materials and their role in SPE. To develop an innovative dipole-assisted SPE technique, a chlorine (Cl)-containing SPE functionality was implanted into a poly(methyl methacrylate) (PMMA) microchip. Herein, diverse analytical techniques including contact angle analysis, Raman spectroscopic analysis, and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis were employed to validate the utility of the implantation protocol of the C-Cl moieties on the PMMA. The analytical results of the X-ray absorption near-edge structure (XANES) analysis also demonstrated the feasibility of the Cl-containing PMMA used as an extraction medium by virtue of the dipole-ion interactions between the highly electronegative C-Cl moieties and the positively charged metal ions.

The fabrication protocol of a dipole-assisted solid phase extraction microchip for the trace metal analysis is presented.

水試料中の微量金属分析のためのダイポールアシスト固相抽出マイクロチップの作製

This paper describes a fabrication protocol for a dipole-assisted solid phase extraction (SPE) microchip available for trace metal analysis in water ...