我们希望感谢巴勃罗至关重要的和强尼莫斯利的帮助, 实地取样, 薇和 Ognevich 的实验室分析帮助纳达尔和伊琳娜。

1. 记录安装和工作原理 <ol> <li> 标识一个研究场, 并安装一个记录, 用于触发样以流量比例为基础收集复合流样本, 这需要监测运河的水平,泵头转速和泵标定方程. </li>
</ol> <img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/56088/56088fig1.jpg"/> 图 1: 分类用于程序自动的采样器复合排水和颗粒水取样的程序. <a href="//ecsource.jove.com/files/ftp_upload/56088/56088fig1large.jpg" target="_blank"> 请单击此处查看此图的较大版本. </a> 
<ol start="3"> <li> 使用安装在泵站旁边的流入和流出运河中的压力传感器监视农场运河的水位. </li>
	<li> 使用安装在泵头上的接近开关来监视泵的转速; 速度由记录记录每分钟转速 (rpm). 
	注意: 接近开关是金属片, 当相互传递时, rpm 数。它们被焊接到泵头上. </li>
	<li> 使用与记录连接的翻斗式雨量计测量降雨量. 
	注: 记录通过无线电遥测通信到位于顾问沼泽地研究和教育中心的一个基地电台。遥测不是控制样本收集的必要条件, 仅用于数据收集和存储. </li>
</ol> 2。排水流量加权水取样 <ol> <li> 使用记录和每个泵的泵标定公式计算排水流量。排水流量加权抽样是实现了一个样, 由记录驱动后, 触发排水量达到. 
	注: 泵速和流速变化超过24小时。分类取样是由排出的水量引起的, 而不是速率。样的程序, 以收集一个样本后, 固定量的排水。根据泵 rpm 的数量, 对流量进行标定. </li>
	<li> 使用 原位 自动取样器在泵站中收集复合水样 (最少500毫升), 并计划在排水事件期间捕获每日复合水样. 
	注: 分类取样器是羽毛的收集坦克使用油管改道通过一个记录, 采取2升样本每2分钟400升. </li>
	<li> 程序示例触发器卷允许每 24 h 放电期间最多30样本. 
	<ol> <li> 程序记录通过以下步骤收集复合流示例: 输入程序和 #8594; 程序和 #8594; 基于流程的取样和 #8594; 采样每1脉冲和 #8594; 30 复合样品和 #8594; 130 毫升和 #8594 的样品体积; 校准样本量 [否] 和 #8594; 输入开始时间 [否] 和 #8594; 程序序列完成. </li>
	</ol> </li> <li> 将流加权复合样本存储在4和 #176 的现场冰箱中, 直到收集和运输到实验室进行分析。
	<li> 从样品采集时起24小时内分析可溶性活性磷的水样。用于总磷 (TP) 分析的样品可以酸化并存储在4和 #176; C 最多28天 15 . </li>
</ol> 3。捕获悬浮粒子 <ol> <li> 放置一系列两个200升 PVC 沉淀池, 在排水期间收集农用运河的排泄水, 以捕获和表征悬浮粒子. 
	<ol> <li> 程序记录通过以下步骤收集悬浮颗粒样品: 程序和 #8594; 基于时间的取样和 #8594; 样品每2分钟和 #8594; 复合样品 [200] 和 #8594; 校准样本量 [否] 和 #8594; 输入开始时间 [否]#8594; 序列完成和 #8594; 按采样按钮. </li>
	</ol> </li> 根据24小时收集期间的水量, <li> 收集设置水箱 (每2分钟2升) 的流量加权排水量. </li> </ol>
 <img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/56088/56088fig2.jpg"/> 图 2: 用于收集排水水的两个200升水箱。悬浮微粒沉淀在罐底, 并在五加仑的水桶中转移。<a href="//ecsource.jove.com/files/ftp_upload/56088/56088fig2large.jpg" target="_blank"> 请单击此处查看此图的较大版本. </a> 
<ol start="3"> <li> 用软管虹吸多余的水, 因为微粒开始在水箱中沉淀. </li>
	<li> 将微粒转移到五加仑的桶中, 将其运回实验室, 并将其放在4和 #176 的冰箱中; C. </li>
	<li> 在沉淀24小时后虹吸多余的水, 并将微粒转移到沉淀沉淀的锥中. </li>
	<li> 在沉淀了至少1小时后, 最后一次虹吸掉多余的水, 在沉降微粒被转移到称量500毫升的螺丝顶罐中, 用于存储在4和 #176;
	<li> 用微粒样品称量罐子. </li>
	<li> 继续进行磷分馏分析, 如海德利·拉玛和斯图尔特所描述的那样 14 . </li>
</ol> <img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/56088/56088fig3.jpg"/> 图 3: 沉淀沉淀锥用于收集沉淀池中捕获的悬浮微粒。 <a href="//ecsource.jove.com/files/ftp_upload/56088/56088fig3large.jpg" target="_blank"> 请单击此处查看此图的较大版本. </a>

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这项研究没有相关的披露。

排水微粒收集的 autosamplers 被放置在数据采集的水泵站附近。电源由太阳能电池板充电的 12 V 电池提供。autosamplers 是由 on-site 数据采集控制的, 它在出口泵运行时打开了 autosamplers, 当水泵停止时将其关闭。取样器进水口的开口位于运河底部0.5 米以上, 从泵站上流。进气线通过安装一个金属钢筋进入运河底部和拉链捆绑进线到钢筋的地方举行。2 l 的样品收集到 200 l 沉淀罐每3分钟收集样品每天。在?...

悬浮微粒的命运和运输是许多研究的主题由于它的作用在富营养化, 特别是在农业系统1,2。对水生系统内微粒物质所含营养素的综合评价是调查许多环境问题的必要条件, 例如, 养分的内部循环和释放到上覆水柱3,基板稳定性、水柱内的光可用性, 以及最终对下游生态系统的水质关注4。以颗粒形式 (有机物或沉积物) 储存的磷 (P) 的数量通常大于水柱5。肯尼et al进行的一项研究。6表明, 在佛罗里达州 Lochloosa 湖沉积的最近沉积物介于1900年和2006的年龄范围之间。这些较年轻的沉积物所含的 P 比水柱中的更近55倍。一种方法来描述微粒可能对某一特定系统产生的潜在影响, 是对在排水过程中排放的沉积物中的磷进行定量清查。收集和分析这些排放的微粒可以帮助估计下游养分富集对敏感生态系统的影响。
风暴事件典型地代表一小部分时间, 但可能贡献多数 P 负荷放电在农田排水。这是因为为了防止农田泛滥, 大量的水会在短时间内排出。降雨强度和流速是控制陆地径流中悬浮沉积物浓度的重要驱动因子7。设计监测方法, 捕捉流加权复合水样本将有助于避免与复杂的, 高强度的降雨事件相关的错误。在像暴风雨这样的高放电事件中, 浓度的快速和剧烈变化可能不代表增量体积的平均污染物浓度。因此, 流加权水样更准确地表示放电事件的浓度, 因为它是一段时间内的负载总和8。最常见的流加权样本是自动收集的离散或复合样本。通过在排放过程中捕获出口的悬浮微粒, 我们可以量化 P 负荷事件的严重性。本研究中所描述的方法有助于捕获以后可以被定性为各种物理和化学性质的微粒。采用连续复合流法与抓斗取样相结合的取样排水流量的新颖性是在整个排水事件期间, 它是更好地表示场条件。然而, 抓取采样是一个 "快照" 的时间, 可能并不完全代表整个事件的效果。
在佛罗里达州南部的大沼泽地农业区 (监管局) 是一个大片的原始沼泽地, 是化和排水的农业, 商业, 和住宅发展。几乎 11亿 m3的水每年从和通过监管局排放到南部和东南9。在监管局的土壤千克, 通常含有超过85% 的有机物重量和少于35% 矿物含量10。运河沉积物通常有低的大块密度 (在 0.14 g cm-3之间到 0.35 g cm-3), 高有机物质内容 (在 31-35%) 和总 P (TP) 价值范围之间 726-1,089 毫克公斤-1 11。
为本示范目的, 在监管局内选择了一个农场。监管局内部水流的 hydroscape, 取决于水泵和重力。监管局辖下的每个农场均包括至少一条主渠道, 以及多个外地沟渠。田间沟渠与主运河垂直。泵通常为双重用途;他们将灌溉用水送到农场, 并在异地排放排水。当田地需要排水时, 主渠中的水就会降低, 从田间流出的水会流入沟渠, 由水力坡度驱动。由于表面上只有轻微的坡度, 在农田上发生的大部分降雨都流经农田沟渠的土壤剖面。 在灌溉期间, 系统被逆转。监管局并无任何排水系统。由于石灰岩基岩的封闭层为土壤的一部分, 地下水位保持在一个特定的高度上。 水通过主要运河被带来;农田沟渠被填满, 水可以渗入土壤剖面, 提高田间水位。通常情况下, 监管局在3月、四月和五月 (旱季) 都会对灌溉用水提出要求, 排放量极少。相比之下, 六月至10月的水排放量 (雨季) 则显著升高。运河银行堤和沟渠的存在允许最小的地表径流作为一个潜在的 P 负荷的来源到农田运河12。
在这个视觉实验中, 我们提出了一种新的方法来捕获流量加权悬浮颗粒在排水事件, 可以以后用于物理化学表征, 如体积密度, 有机物含量, 和 P 分馏13 ,14。

<table width="602">
	<tbody>
		<tr height="42">
			<td height="42" style="width:216px;height:42px;">Datalogger</td>
			<td style="width:83px;">Campbell Scientific</td>
			<td style="width:137px;"></td>
			<td style="width:167px;">model CR1000</td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Auto-sampler</td>
			<td style="width:83px;">ISCO</td>
			<td style="width:137px;"></td>
			<td>model 3700</td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Pressure transducer</td>
			<td style="width:83px;">KPSI</td>
			<td style="width:137px;"></td>
			<td>model 700</td>
		</tr>
		<tr height="42">
			<td height="42" style="width:216px;height:42px;">Tipping bucket rain guage</td>
			<td style="width:83px;">Texas Electronics</td>
			<td style="width:137px;"></td>
			<td>model TR-525</td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Potassium Chloride</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">7447-40-7</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Sodium Hydroxide</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">1310-73-2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Hydrochloric Acid</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">7647-01-0</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Sulfuric Acid</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">7664-93-9</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Potassium Persulfate</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">7727-21-1</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:216px;height:42px;">Ammonium Molybdate Tetrahydrate</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">12054-85-2</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">L-Ascorbic Acid</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">50-81-7</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:216px;height:42px;">100 mg/L Anhydrous Phosphate Standard</td>
			<td style="width:83px;">ERA</td>
			<td style="width:137px;">061</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:216px;height:42px;">Antimony Potassium Tartrate Trihydrate</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">28300-74-5</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Durapore Membrane Filters</td>
			<td style="width:83px;">Millipore</td>
			<td style="width:137px;">HVLP04700</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Whatman #41 Filter Paper</td>
			<td style="width:83px;">Whatman</td>
			<td style="width:137px;">1441-150</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="width:216px;height:63px;">Fixed Speed Reciprocal Shaker E6010</td>
			<td style="width:83px;">Eberbach Corporation</td>
			<td style="width:137px;">E6010.00</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Disposable Culture Tubes</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">14-961-29</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:216px;height:42px;">Allegra 25R Centrifuge</td>
			<td style="width:83px;">Becker Coulter</td>
			<td style="width:137px;">U.S. 605168-AC</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="width:216px;height:63px;">Parafilm</td>
			<td style="width:83px;">Bemis Company Inc PM 999</td>
			<td style="width:137px;">13-374-12</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Oak Ridge Centrifuge Tubes</td>
			<td style="width:83px;">Nalgene</td>
			<td style="width:137px;">3119-0050</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="width:216px;height:63px;">Fisherbrand 20mL HDPE Scintillation Vials with Urea Cap</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">03-337-23C</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="width:216px;height:63px;">Fisherbrand&#160;Natural Polypropylene Jars with White Polypropylene Unlined Cap</td>
			<td style="width:83px;">Fisher</td>
			<td style="width:137px;">02-912-024A</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="width:216px;height:42px;">0.45 membrane filters</td>
			<td style="width:83px;">Cole-Parmer</td>
			<td>Item # UX-15945-25</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">100 ml digestion tubes</td>
			<td style="width:83px;">Fisher&#160;</td>
			<td>TC1000-0735</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">Glass funnels</td>
			<td style="width:83px;">Fisher</td>
			<td>03-865</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Spectronic 20 Genesys</td>
			<td style="width:83px;">Thermo-Fisher</td>
			<td>4001-000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="width:216px;height:21px;">QuikChem</td>
			<td style="width:83px;">Latchat</td>
			<td style="width:137px;">8500</td>
			<td></td>
		</tr>
	</tbody>
</table>

capturing flow-weighted water and suspended particulates from agricultural canals during drainage events

本研究的目的是描述在排水事件过程中用来捕获农田沟渠中的流动加权水和悬浮颗粒物的方法。农田运河可以由易受运输的磷 (P) 等营养素丰富。悬浮颗粒物中的磷能显著促进排水中的 P 总负荷。在离散排水事件中, 进行了沉淀池试验, 捕捉悬浮颗粒物。在排水事件的整个过程中, 在两个 200 L 沉淀池中收集了大量的农田渠排放水, 以此来代表被排放的水的复合子。沉淀沉淀锥最终用于解决悬浮粒子。这是通过从沉淀池虹吸水通过锥。然后收集颗粒物进行物理化学分析。

本研究中所描述的方法, 使我们能够捕捉水和颗粒物质, 正在排出在农场运河抽水事件。收集的水和微粒是流加权的, 这意味着它们代表了整个泵浦事件的持续时间, 而不仅仅是一次性的快照;使其高度代表性的类型的材料被释放。水和悬浮颗粒物可以储存, 以分析各种物理和化学参数。在这篇文章中, 我们总结了监管局辖下三农场运河内悬浮粒子的一些性质。一些物理化学分...

Watch this Scientific Journal Video about Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events at JoVE.com

Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events

以微粒形式存在的养分对农业排水系统的整体负荷有显著的贡献。本研究介绍了一种新的方法, 以捕捉流量加权水和悬浮颗粒从农田渠排水在整个期间的排水事件。

在排水过程中捕获农用运河中的流动加权水和悬浮颗粒

The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage ...

capturing-flow-weighted-water-suspended-particulates-from

Universidad de Cartagena UDEC

Research

JoVE Journal

Environment

15.8K 次观看.  University of Florida. 以微粒形式存在的养分对农业排水系统的整体负荷有显著的贡献。本研究介绍了一种新的方法, 以捕捉流量加权水和悬浮颗粒从农田渠排水在整个期间的排水事件。

视频: Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events

Colorimetric Paper-based Detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from Large Volumes of Agricultural Water

This protocol describes rapid colorimetric detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from large volumes (10 L) of agricultural waters. Here, water is filtered through sterile Modified Moore Swabs (MMS), which consist&#160;of a simple gauze filter enclosed in a plastic cartridge, to concentrate bacteria. Following filtration, non-selective or selective enrichments for the target bacteria are performed in the MMS. For colorimetric detection of the target bacteria, the enrichments are then assayed using paper-based analytical devices (&#181;PADs) embedded with bacteria-indicative substrates. Each substrate reacts with target-indicative bacterial enzymes, generating colored products that can be detected visually (qualitative detection) on the &#181;PAD. Alternatively, digital images of the reacted &#181;PADs can be generated with common scanning or photographic devices and analyzed using ImageJ software, allowing for more objective and standardized interpretation of results. Although the biochemical screening procedures are designed to identify the aforementioned bacterial pathogens, in some cases enzymes produced by background microbiota or the degradation of the colorimetric substrates may produce a false positive. Therefore, confirmation using a more discriminatory diagnostic is needed. Nonetheless, this bacterial concentration and detection platform is inexpensive, sensitive (0.1 CFU/ml detection limit), easy to perform, and rapid (concentration, enrichment, and detection are performed within approximately 24&#160;hr), justifying its use as an initial screening method for the microbiological quality of agricultural water.

Colorimetric Paper-based Detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from Large Volumes of Agricultural Water

A protocol involving integrated concentration, enrichment, and end-point colorimetric detection of foodborne pathogens in large volumes of agricultural water is presented here. Water is filtered through Modified Moore Swabs (MMS), enriched with selective or non-selective media, and detection is performed using paper-based analytical devices (&#181;PAD) imbedded with bacterial-indicative colorimetric substrates.

比色纸为基础的检测<em&gt;大肠杆菌</em&gt;<em&gt;沙门氏菌</em&gt;属，和<em&gt;单核细胞增生李斯特氏菌</em&gt;从农业用水大容量

This protocol describes rapid colorimetric detection of Escherichia coli, Salmonella spp., and Listeria monocytogenes from large volumes (10 L) of ...

科研

环境科学

Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading

Eutrophication is a water quality issue in lakes worldwide, and there is a critical need to identify and control nutrient sources. Internal phosphorus (P) loading from lake sediments can account for a substantial portion of the total P load in eutrophic, and some mesotrophic, lakes. Laboratory determination of P release rates from sediment cores is one approach for determining the role of internal P loading and guiding management decisions. Two principal alternatives to experimental determination of sediment P release exist for estimating internal load: in situ measurements of changes in hypolimnetic P over time and P mass balance. The experimental approach using laboratory-based sediment incubations to quantify internal P load is a direct method, making it a valuable tool for lake management and restoration.
Laboratory incubations of sediment cores can help determine the relative importance of internal vs. external P loads, as well as be used to answer a variety of lake management and research questions. We illustrate the use of sediment core incubations to assess the effectiveness of an aluminum sulfate (alum) treatment for reducing sediment P release. Other research questions that can be investigated using this approach include the effects of sediment resuspension and bioturbation on P release.
The approach also has limitations. Assumptions must be made with respect to: extrapolating results from sediment cores to the entire lake; deciding over what time periods to measure nutrient release; and addressing possible core tube artifacts. A comprehensive dissolved oxygen monitoring strategy to assess temporal and spatial redox status in the lake provides greater confidence in annual P loads estimated from sediment core incubations.

Lake eutrophication is a water quality issue worldwide, making the need to identify and control nutrient sources critical. Laboratory determination of phosphorus release rates from sediment cores is a valuable approach for determining the role of internal phosphorus loading and guiding management decisions.

实验室确定的磷通量湖泊沉积物作为内部磷载入一个测量

Eutrophication is a water quality issue in lakes worldwide, and there is a critical need to identify and control nutrient sources. Internal phosphorus (P) ...

Measurement of Greenhouse Gas Flux from Agricultural Soils Using Static Chambers

Measurement of greenhouse gas (GHG) fluxes between the soil and the atmosphere, in both managed and unmanaged ecosystems, is critical to understanding the biogeochemical drivers of climate change and to the development and evaluation of GHG mitigation strategies based on modulation of landscape management practices. The static chamber-based method described here is based on trapping gases emitted from the soil surface within a chamber and collecting samples from the chamber headspace at regular intervals for analysis by gas chromatography. Change in gas concentration over time is used to calculate flux. This method can be utilized to measure landscape-based flux of carbon dioxide, nitrous oxide, and methane, and to estimate differences between treatments or explore system dynamics over seasons or years. Infrastructure requirements are modest, but a comprehensive experimental design is essential. This method is easily deployed in the field, conforms to established guidelines, and produces data suitable to large-scale GHG emissions studies.

This article showcases the static chamber-based method for measurement of greenhouse gas flux from soil systems. With relatively modest infrastructure investments, measurements may be obtained from multiple treatments/locations and over timeframes ranging from hours to years.

从农业土壤使用静态钱伯斯温室气体流量测量

Measurement of greenhouse gas (GHG) fluxes between the soil and the atmosphere, in both managed and unmanaged ecosystems, is critical to understanding the ...

EPA Method 1615. Measurement of Enterovirus and Norovirus Occurrence in Water by Culture and RT-qPCR. Part III. Virus Detection by RT-qPCR

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. This method was developed with the goal of having a standardized method for use in multiple analytical laboratories during monitoring period 3 of the Unregulated Contaminant Monitoring Rule. Herein we present the protocol for extraction of viral ribonucleic acid (RNA) from water sample concentrates and for quantitatively measuring enterovirus and norovirus concentrations using reverse transcription-quantitative PCR (RT-qPCR). Virus concentrations for the molecular assay are calculated in terms of genomic copies of viral RNA per liter based upon a standard curve. The method uses a number of quality controls to increase data quality and to reduce interlaboratory and intralaboratory variation. The method has been evaluated by examining virus recovery from ground and reagent grade waters seeded with poliovirus type 3 and murine norovirus as a surrogate for human noroviruses. Mean poliovirus recoveries were 20% in groundwaters and 44% in reagent grade water. Mean murine norovirus recoveries with the RT-qPCR assay were 30% in groundwaters and 4% in reagent grade water.

Here we present a procedure to quantify enterovirus and norovirus in environmental and drinking waters using reverse transcription-quantitative PCR. Mean virus recovery from groundwater with this standardized procedure from EPA Method 1615 was 20% for poliovirus and 30% for murine norovirus.

EPA方法1615测量肠道病毒和诺瓦克病毒发生水由文化和RT-qPCR的了。第三部分。病毒检测用RT-qPCR的

EPA Method 1615 measures enteroviruses and noroviruses present in environmental and drinking waters. This method was developed with the goal of having a ...

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.

表征和被动采样的应用在农药水监测

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

Extraction of Organochlorine Pesticides from Plastic Pellets and Plastic Type Analysis

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment during manufacturing and transport. Because of their environmental persistence, they are widely distributed in the oceans and on beaches all over the world. They can act as a vector of potentially toxic organic compounds (e.g., polychlorinated biphenyls) and might consequently negatively affect marine organisms. Their possible impacts along the food chain are not yet well understood. In order to assess the hazards associated with the occurrence of plastic pellets in the marine environment, it is necessary to develop methodologies that allow for rapid determination of associated organic contaminant levels. The present protocol describes the different steps required for sampling resin pellets, analyzing adsorbed organochlorine pesticides (OCPs) and identifying the plastic type. The focus is on the extraction of OCPs from plastic pellets by means of a pressurized fluid extractor (PFE) and on the polymer chemical analysis applying Fourier Transform-InfraRed (FT-IR) spectroscopy. The developed methodology focuses on 11 OCPs and related compounds, including dichlorodiphenyltrichloroethane (DDT) and its two main metabolites, lindane and two production isomers, as well as the two biologically active isomers of technical endosulfan. This protocol constitutes a simple and rapid alternative to existing methodology for evaluating the concentration of organic contaminants adsorbed on plastic pieces.

Microplastics act as vector of potentially toxic organic contaminants with unpredictable effects. This protocol describes an alternative methodology for assessing the levels of organochlorine pesticides adsorbed on plastic pellets and identifying the polymer chemical structure. The focus is on pressurized fluid extraction and attenuated total reflectance Fourier transform infrared spectroscopy.

从塑料颗粒中提取有机氯农药和塑料类型分析

Plastic resin pellets, categorized as microplastics (&#8804;5 mm in diameter), are small granules that can be unintentionally released to the environment ...

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.

农业流域营养盐和泥沙的连续河道监测

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

农业经营条件下土壤侵蚀和沉积与土壤碳酸盐浓度关系的测量与制图

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

Composition and Properties of Aquafaba: Water Recovered from Commercially Canned Chickpeas

Chickpea and other pulses are commonly sold as canned products packed in a thick solution or a brine. This solution has recently been shown to produce stable foams and emulsions, and can act as a thickener. Recently interest in this product has been enhanced through the internet where it is proposed that this solution, now called aquafaba by a growing community, can be used a replacement for egg and milk protein. As aquafaba is both new and being developed by an internet based community little is known of its composition or properties. Aquafaba was recovered from 10 commercial canned chickpea products and correlations among aquafaba composition, density, viscosity and foaming properties were investigated. Proton NMR was used to characterize aquafaba composition before and after ultrafiltration through membranes with different molecular weight cut offs (MWCOs of 3, 10, or 50 kDa). A protocol for electrophoresis, and peptide mass fingerprinting is also presented. Those methods provided valuable information regarding components responsible for aquafaba functional properties. This information will allow the development of practices to produce standard commercial aquafaba products and may help consumers select products of superior or consistent utility.

Aquafaba is a viscous juice from canned chickpea that, when stirred vigorously, produces a relatively stable white froth or foam. The primary research goal is to identify the components of aquafaba that contribute viscosifying/thickening properties using nuclear magnetic resonance (NMR), ultrafiltration, electrophoresis, and peptide mass fingerprinting.

Aquafaba 的成分和性质: 从商用罐装鹰嘴中回收的水

Chickpea and other pulses are commonly sold as canned products packed in a thick solution or a brine. This solution has recently been shown to produce ...

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.

春季池塘连续水文水质监测

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