作者想感谢宾夕法尼亚州立大学物理工厂办公室提供部分资金支持这个项目。农业部-区域研究项目 W-3170 也提供了部分资金。我们要感谢以法莲 Govere 协助进行分析工作。我们最深切的谢意是查尔斯沃克, 他的工程设计和施工技巧使我们有可能进行这项工作。

1. 选择土壤取样地点
<ol><li>通过航空摄影和现场访问的地点进行识别, 这些地方已经接受了废水灌溉和那些没有的。</li>
	<li>选择几个代表性的站点, 从中取样, 密切注意可能的景观差异 (特别是景观的位置, 如山顶, 山坡, 脚趾坡, 和抑郁症), 水, 土壤和植物可能会相互作用不同。</li>
	<li>确定景观的一部分作为山顶, 侧面斜坡, 脚趾斜坡, 或抑郁症。根据其主要特征对代表性站点进行分类。 注: 在本实验中, 遗址被确定为非灌溉峰会、灌溉峰会、非灌溉抑郁症或灌溉抑郁症。</li>
	<li>确定每个地点的位置和地点, 从每个独特的代表性站点抽取样本。 注意: 通常, 与熟悉环境统计的统计员进行的讨论在这一点上将非常有用, 并可防止以后对统计分析的关注。</li>
	<li>在每个计划的样本位置放置一个标记标志, 并使用 GPS 坐标在地图上记录计划样本站点的位置。</li>
</ol>2. 收集土壤样品
<ol><li>确定将用于收集土壤样品的设备。 注: 对于浅层 (例如, 不到300毫米深) 的土壤样品, 如果土壤足够软, 则该试验所用的圆柱形土取样器 (辅助图 1) 通常可以用落锤驱动到土壤中。在这里描述的实验中, 一个液压钻机被用来让样品从深度收集到1200毫米。</li>
</ol><img alt="Supplemental Figure 1" src="/files/ftp_upload/57181/57181SF1.jpg"> 补充图 1: 用于取样的钻机。
<ol start="2"><li>将钻机运到现场进行取样。</li>
	<li>在开始钻机之前, 戴上安全帽、手套和防护护目镜。</li>
	<li>在钻机上通电, 并使旋转头足够低, 以允许安装凯利棒。 注: 钻杆是将钻机的驱动头连接到取样器的金属杆。</li>
	<li>将凯利酒吧插入旋转头。</li>
	<li>将塑料衬垫/取样管插入金属试样管中, 并将切削头附着在金属试样管的底部。在这里描述的应用, 使用150厘米长和90毫米外径 (OD) 塑料衬里安装成一个200毫米长和100毫米 OD/90 毫米内径 (ID) 金属样品管。</li>
	<li>将金属样品管连接到钻杆上, 使用装有两个驱动器头。</li>
	<li>操作钻机将样品管移动大约150毫米入土壤。 注: 这将提供一个100毫米样品在塑料班轮和允许一个50毫米空间在样品的顶部举行水 ponded 在样品当饱和的水力电导率测量在实验室获得。这也将有助于避免压缩土壤样品在其收集。</li>
	<li>使用钻机液压系统从土壤中取出金属试样管。</li>
	<li>从驱动头上取出金属试样管。然后从金属试样管中取出所持土样的塑料试样管, 用小心不要从塑料试样管内流失土壤, 而不是压缩土或挤压塑料试样管的两侧。</li>
	<li>将端盖放在塑料样品管的每一端, 用红色的末端在土壤样品的顶端和黑色的土壤样品的底部。将端盖贴在套筒上, 以避免污染或样品中的水流失。</li>
	<li>将样品直立放置以供运输回实验室。</li>
	<li>继续取样到最深的兴趣深度, 重复步骤2.6–2.12。</li>
</ol>3. 建立恒定水头、多柱、土壤水力电导率设置
注: 水力电导率实验室仪器根据工作由步行者10。它涉及到使用一个渗透仪, 它被构造成将样品的外边缘和包含环的圆柱体之间的流动分离到土壤基质中。下面提到的任何 PVC 管道的 ID 都不是严格的公差。有些可能很合身, 其他的可能需要一些工作 (光砂)。
<ol><li>获得100毫米长, 96 毫米 ID/114 毫米 OD 附表 40 PVC 管。</li>
	<li>获得100毫米长, 73 毫米 ID/89 毫米 OD 附表 40 PVC 管和机器它有一个5毫米锥形切削刃。提供这与89毫米塑料衬垫, 以适应外径。</li>
	<li>切断步骤3.2 中提到的附表 40 PVC 管的底部20毫米, 并保留它供以后使用。</li>
	<li>从6毫米厚的灰色 PVC 板, 削减 155 x 155 毫米2。在正方形的中心, 机器正方形包含60–70毫米的圆的开头。</li>
	<li>切割6毫米厚片的73毫米 OD/63 mm ID 附表 40 PVC 管。 注:73 毫米的淋浴排水管, 适合73毫米的 ID 附表 40 pvc 管可以切割和工作良好, 如果73毫米 OD 附表 40 pvc 管道不可用。</li>
	<li>使用 pvc 水泥, 将 6 mm 厚片73毫米外径 pvc (从步骤 3.5) 20 毫米低于顶部的 89 mm 外径 pvc (从步骤 3.2)。</li>
	<li>在步骤3.6 中使用的 pvc 水泥干燥后, 将两个 pvc 钢瓶中心放在6毫米板上, 然后使用 pvc 水泥将其连接到板材上。</li>
	<li>钻一个孔在外面 pvc 圆筒, 集中大约15毫米在灰色 PVC 正方形之上, 容纳14毫米 PVC 适配器以有刺的末端。</li>
	<li>使用 PVC 水泥将适配器水泥到位。</li>
	<li>将19毫米 OD/13 毫米 ID 塑料油管连接到适配器的有刺端。</li>
	<li>水泥 20 mm 的附表 40 PVC 提到的步骤3.4 到底部的灰色 PVC 广场, 以开放为中心。</li>
	<li>切出一个80–85毫米直径圆片6毫米 x 18 克丝网 (镀锌钢天沟守卫工作很好为此) 插入到89毫米 od pvc 从顶部, 以便它在73毫米 od pvc 的6毫米厚实的切片。</li>
	<li>选择 19 x 184 x 2438 毫米3板, 并将其切成两半, 将每个长度修剪到 1180 mm。</li>
	<li>切出的6–125毫米孔相隔70毫米的板。</li>
	<li>将金属丝网放在板孔下, 并将其附着在纸板上 (使用钉枪)。</li>
	<li>将140毫米 (顶部开口) x 19 毫米 (喷口 OD) 漏斗置于丝网下方, 并将其附着在板上;在漏斗的边缘放置粘合剂填塞, 以消除漏斗顶部与木材之间的空隙。</li>
	<li>
建造一个750毫米高的木框架, 以保持板与6孔 (见步骤3.13 和 3.14) 约350毫米以上的框架底部。
	<ol>
<li>准备这个框架的组成部分, 包括一个基地, 两个框架两端, 两个稳定的腿, 一个较低的加固基地, 稳定的基础, 中心稳定后板, 和顶部后板。</li>
		<li>将板切成 19 x 184 x 1180 毫米3作为底座。</li>
		<li>将两个板切割为 19 x 184 x 750 毫米3 , 每帧结束。</li>
		<li>切割两个板, 以创建一个 19 x 184 x 600 毫米3稳定腿的每一端。</li>
		<li>切割一个板到 19 x 184 x 1180 毫米3 , 作为一个较低的加固基地直接在板下与125毫米孔钻孔在它 (见步骤 3.14)。</li>
		<li>将一个板子剪成 19 x 184 x 1219 毫米3 , 作为固定在两条稳定腿前方或后方的稳定基座。</li>
		<li>将板切割成 19 x 184 x 1219 毫米3作为中心稳定后板。</li>
		<li>切割一个板到 19 x 184 x 1219 毫米3作为一个顶部后板, 以增加额外的稳定性, 其中一个排水沟将附加。 注: 顶部后板和附着的排水沟应在高度, 这样, 底部的排水沟是近似在同一海拔的土壤样品套管将是当样品到位。</li>
	</ol>
</li>
</ol><img alt="Supplemental Figure 2" src="/files/ftp_upload/57181/57181SF2.jpg"> 补充图 2: 饱和液压电导装置的前视图.<a href="/files/ftp_upload/57181/57181SF2large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<ol start="18"><li>
准备补给和排水沟。 注: 每个塑料天沟约120毫米横跨和1219毫米长, 并装有端盖。<ol>
<li>在排水槽的一端盖上钻孔, 并在供应槽的一端, 在每个孔中容纳13毫米 HB x 可能尼龙刺头适配器。</li>
		<li>在供应槽的另一端盖上钻孔, 以容纳25毫米的 PVC 管道, 以便排水回供应容器。</li>
		<li>在需要的情况下, 将倾斜的 PVC 连接水泥, 以便将水排水回供应容器。</li>
		<li>切割一个40毫米高天沟年底帽, 以适应在供应天沟约10厘米从 PVC 连接的插座。</li>
		<li>在该端盖的顶部切下一个梯形凹槽, 大约20毫米深, 30 毫米宽在底部和50毫米宽在凹槽的顶端。 注: 这将采取行动, 保持一个恒定的头在供应排水沟。</li>
		<li>将排水槽放在漏斗下面, 使其停留在木框架的下部加固底座上。</li>
		<li>使用乙烯槽衣架将供应槽连接到顶部后板。</li>
	</ol>
</li>
</ol><img alt="Supplemental Figure 3" src="/files/ftp_upload/57181/57181SF3.jpg"> 补充图 3: 供水排水沟的末端视图.<a href="/files/ftp_upload/57181/57181SF3large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<ol start="19"><li>
准备水源。
	<ol>
<li>将塑料管材连接到供应槽和排水槽中的尼龙带刺端适配器。</li>
		<li>将一个大浴缸放在与导电装置相邻的地板上, 作为供应容器。 注: 应选择浴缸, 以保持足够的水, 至少24小时的测量。</li>
		<li>将一个小型潜水泵放入浴缸中, 通过塑料油管将其连接到供应槽的入口端。</li>
		<li>将小塑料油管连接到壁流插座的带刺端适配器 (3.9), 并将油管的非连接端插入排水槽。</li>
		<li>用水填满供应容器。</li>
		<li>插入泵并运行它, 以填补供应排水沟。确保将水输送到供应槽的速度足以使供应槽几乎满溢而不溢出。</li>
	</ol>
</li>
	<li>
准备一个 "实践土壤样本", 以确定所需的任何修改。
	<ol>
<li>将 "练习" 土壤样品放入塑料取样套筒中, 在土壤顶部与塑料套筒顶部之间留出约50毫米的空间。</li>
		<li>用双层的棉布盖住样品的下端和套筒。用足够大小的橡皮筋将棉布在取样套筒上。</li>
		<li>将练习土壤样品和套筒放入一盆水中, 填充到袖子高度的1/3 左右, 棉布端在水中。</li>
		<li>几个小时后, 把浴缸里的水提高到样品高度的大约2/3。在允许样品过夜后, 将浴缸填入土壤样品的顶端 (而不是袖子的顶端)。</li>
	</ol>
</li>
	<li>将土壤样品放在89毫米外径的 PVC 管上面, 轻轻地将其压在管子上, 使 pvc 管削尖的边缘压入土壤几毫米, 以允许土壤底部在屏幕上休息。 注: 棉布将需要松动的橡皮筋, 以允许这一点。另外, 请注意, 试样套筒中的土壤顶部应与供应槽底部近似水平, 试样套筒的顶部应与供应槽顶部近似水平。</li>
	<li>
在土壤样品的顶端提供水。
	<ol>
<li>打开水泵, 填充供给槽。</li>
		<li>确保引流管的末端放在排水槽内, 排水槽的出水口与塑料油管紧密连接, 并将其置于较低海拔的排水管或容器中。</li>
		<li>使用6毫米油管, 创建一个虹吸从供应排水沟到土壤顶部。</li>
	</ol>
</li>
	<li>收集从漏斗排出的土壤核心的水样。 注: 根据研究标准, 应收集样品以获得足够的水所需的时间长短, 以达到实验所需的精确度。</li>
	<li>检查是否有泄漏或未预料的问题。</li>
	<li>根据所需的时间, 确定需要多少时间来收集足够的水 (或由研究小组确定的其他容积), 以填补大约100毫升的烧杯。</li>
	<li>通过在塑料土样容器内插入一个小螺丝刀或另一种类似的执行器来创建模拟的 "壁流", 以确认此通道产生的多余流量通过引流管流向排水槽。</li>
	<li>根据本练习运行中发现的任何问题修改安装程序。</li>
</ol>4. 获取土壤水力电导率值
<ol><li>根据步骤3.20 中为练习运行提供的指示, 将从现场收集的土壤样品棉布, 覆盖在与橡胶带保持在一起的样品的底部。</li>
	<li>启动泵并允许供应槽填充。检查是否有泄漏。</li>
	<li>将样品放到液压电导装置上, 并进行实际运行。注意不要在搬运过程中压缩样品。</li>
	<li>设置虹吸管, 将水从补给槽中移到塑料套筒所含土壤的表面。</li>
	<li>最初, 开始收集水从漏斗每10–20分钟, 以获得一个想法, 需要多长时间取样和多频繁取样。记录时间和水质量/体积在每个样品时间为每个土壤样品。</li>
	<li>寻找顺序样品包含等量的水。3–5样品含有相同量的水后, 样品有可能达到稳定状态。 注: 为确保已达到稳定状态, 可能需要另外安排1小时的额外样品。</li>
	<li>利用达西定律计算饱和水力电导率; <img alt="Equation 1" src="/files/ftp_upload/57181/57181eq1.jpg"> 地方 Ksat = 饱和水力电导率 (升/吨) V = 流经核心的水的稳态容积 (L3) l = 样品长度 (l) A = 芯 (L2) 的剖面区域, 水流过。对于此设置, <img alt="Equation 2" src="/files/ftp_upload/57181/57181eq2.jpg"> t = 时间 (t) (h2- h1) = 液压头差 (L);对于这个设置, 它是在土壤表面和土壤样品的底部的水 ponded 的顶部之间的距离。</li>
</ol>

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M., White, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Designs+for+disc+permeameters.">Designs for disc permeameters.</a> Soil Science Society of America Journal. 52 (5), 1205-1215 (1988).</li><li>Clothier, B. E., White, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+sorptivity+and+soil+water+diffusivity+in+the+field.">Measurement of sorptivity and soil water diffusivity in the field.</a> Soil Science Society of America Journal. 45 (2), 241-245 (1981).</li><li>Ankeny, M. D., Ahmed, M., Kaspar, T. C., Horton, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simple+field+method+for+determining+unsaturated+hydraulic+conductivity.">Simple field method for determining unsaturated hydraulic conductivity.</a> Soil Science Society of America Journal. 55 (2), 467-470 (1991).</li><li>Larson, Z. 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> Long-term treated wastewater irrigation effects on hydraulic conductivity and soil quality at Penn State's Living Filter. , (2010).</li></ol>

作者没有什么可透露的。

收集现场、未受干扰的土壤样品和获得其水力电导值的能力在获得现场数据代表方面具有重要意义。为了最好地代表田间条件, 重要的是使用土壤样本保持在物理状态代表他们的环境在田间。例如, 从现场收集的土壤样品, 然后由抽样或处理诱发压实, 将会遇到影响饱和水力传导性的结构变化。
在受控实验室设置中测量土壤水力电导率也很重要。然而, 使用实验室方法来计算饱?...

几十年来, 把处理过的废水从市镇排放到溪流是一种标准做法。这类废水主要用于减少由于废水排出而导致接收水域微生物的生物耗氧量的可能性。微生物的耗氧量会降低废水中的有机物, 从而减少水体排出的氧气量, 从而危害水生生物, 包括鱼类。
近几十年来, 人们对无机营养素、某些金属和废水中的其他化学物质产生了危害。由于 Kolpin 发表的一项研究 。1, 对以前未考虑过的一系列化学品的更大关注已经演变。这项由美国地质学会出版的研究, 提高了人们对在美国由于污水处理设施排出的河流和溪流中各种个人护理产品和其他化学品的认识。
自二十世纪六十年代代初以来, 宾州州立大学的研究人员研究并开发了一种在潮湿地区具有独特性的替代污水排放实践。污水被用于由大学管理的森林和被裁剪的土地, 而不是将处理过的废水排放到溪流中, 从而直接影响水流质量。这个应用领域, 绰号 "生活过滤器", 当前接受所有从校园产生的废水并且一些从自治市。这减少了过量营养素进入切萨皮克湾的溪流的可能性, 保护当地冷水渔业免受对鱼类有害的温水废水的排放, 并防止其他化学品的运送。包含在直接接触水生生态系统的废水中。
然而, 行为变化的后果总是存在的, 而这种替代性使用设施对此并不免疫。关于废水的应用是否对土壤允许水渗入土壤表面23、4、5以及造成更大的径流的能力产生了负面影响, 出现了一些问题,是否有可能污染当地的水井与化学品 (营养素, 抗生素或其他药物化合物, 个人护理产品) 所含的废水, 以及这些化学品是否正在创造负环境影响, 例如通过将化学物质吸收到植物中生长的6植株上, 或在现场7土壤生物中抗生素耐药性的发展。
由于其中的一些问题, 本研究旨在确定污水灌溉对土壤水力传导饱和度的影响。所采用的方法涉及从灌溉区内外的选定地点收集土壤, 并将土壤样品容器大小与实验室设置相匹配。土壤样品容器要适应实验室仪器和水的作用, 通过样品中的土壤基质从土壤和土壤样品容器中向下移动的水中分离出来。该协议描述了如何构造实验室设备以确保发生这种情况。
土壤样品收集使用一个液压核心取样器连接到拖拉机。土壤核心从起伏的景观中的选定区域收集, 并保留在安装在土芯取样器中的塑料套筒中。这些核心是收集从一个黑格斯敦淤泥沃土, 位于山顶景观位置或在 depressional 地区。六个代表首脑会议和六个 depressional 地点从灌溉区取样 (总共12个灌区取样地点)。此外, 还从毗邻的非灌溉区 (总共六个非灌溉场址) 取样了三个首脑会议和三个 depressional 场址。在每个地点收集最多六个核心的最大深度约为1200毫米, 每芯样品约150毫米长 (样品的100毫米被包含在塑料套筒和50毫米被包含在金属取样器的切削头中。).从金属取样器中取出后, 含有所收集的土芯的塑料套管装有端盖, 直立输送到实验室, 并存放在直立, 直到用于确定饱和水力电导率。同时, 在每个深度收集土壤样品, 以确定土壤和土壤溶液浓度的钙 (钙), 镁 (镁) 和钠 (Na) 使用 Mehlich 3 萃取估计土壤浓度8和去离子水1:2 土壤质量比的萃取物: 水质量。采用电感耦合等离子体原子发射光谱法 (AES) 对水提物进行了化学分析, 计算了钠吸附比 (SAR)。
对饱和水力电导率的测定主要采用恒定水头法9。一种含有钙和钠盐的溶液来模拟出水电导率 (EC) 和 SAR 的出水, 这样土壤就会暴露在水质变量中, 类似于在田间应用的废水。在这种情况下, 欧共体是 1.3 dS/米和 sar 是 3, 反映了欧共体和 sar 最近几年在样品期间之前。[技术上说, SAR 的单位是 (milliequivalents/公升)½并且通常不被辨认在文学。
对克鲁特和埃弗里特·德克森9恒水头法的改造, 是通过沃克8的流动分离器的开发, 防止在土基质外发生的柱流被列入土液的估算中。电导 率。该流量分离器是使用聚氯乙烯 (PVC) 管材选择和加工, 以配合土壤样品大小。屏幕支持土壤样品, 并允许通过土壤基质的水流出样品的底部。第二个插座发出的水流出的塑料套管内, 从而消除所谓的 "壁流" 不正确地包括在估计的水量, 通过土壤基质。

<table>
	<tbody>
		<tr>
			<td>Sampling equipment:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Soil Sampler Drill Rig</td>
			<td>Giddings Machine Co. Inc</td>
			<td>#25-TS / Model HDGSRTS</td>
			<td>* NOTE: This model is comparable to the model we utilized but which is no longer produced</td>
		</tr>
		<tr>
			<td>Kelly Bar</td>
			<td>Giddings Machine Co. Inc</td>
			<td>#KB-208 8 Ft. Kelly Bar</td>
			<td></td>
		</tr>
		<tr>
			<td>Soil Sample Collection Tube</td>
			<td>Giddings Machine Co. Inc</td>
			<td>#ZC-180 4-3/4&#8221; X 7-1/4&#8221;</td>
			<td></td>
		</tr>
		<tr>
			<td>Soil Collection Tube Bit</td>
			<td>Giddings Machine Co. Inc</td>
			<td>#ZC-190 4-3/4&#8221; Standard Relief</td>
			<td></td>
		</tr>
		<tr>
			<td>Plastic Liner for Soil Sample</td>
			<td>Giddings Machine Co. Inc</td>
			<td>#ZC-208 3-5/8&#8221; x 6&#8221;</td>
			<td>Enough for the number of samples being collected</td>
		</tr>
		<tr>
			<td>Black end caps a for bottom of sample liners</td>
			<td>Giddings Machine Co. Inc</td>
			<td></td>
			<td>To retain samples in liners</td>
		</tr>
		<tr>
			<td>Red end caps a for top of sample liners</td>
			<td>Giddings Machine Co. Inc</td>
			<td></td>
			<td>To retain samples in liners</td>
		</tr>
		<tr>
			<td>Cooler Chest</td>
			<td></td>
			<td></td>
			<td>Store &#38; maintain samples upright in sample liners during transport from field to lab</td>
		</tr>
		<tr>
			<td>Protective gear:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Hardhats, googles, and gloves</td>
			<td></td>
			<td></td>
			<td>other items as needed for personal protection</td>
		</tr>
		<tr>
			<td>Saw</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Drill and bits</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>PVC Cement</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>6 to 8 - 19 mm x 184 mm x 2438 mm boards</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>2 &#8211; barbed fittings; 13 mm HB x MGHT</td>
			<td></td>
			<td></td>
			<td>to connect plastic tubing to supply gutter and to drainage gutter</td>
		</tr>
		<tr>
			<td>6 &#8211; barbed fitting</td>
			<td></td>
			<td></td>
			<td>to connect plastic tubing to outer PVC cylinder to allow for water drainage</td>
		</tr>
		<tr>
			<td>3000 mm long - 19 mm OD / 13 mm ID plastic tubing</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>6 &#8211; 85 mm diameter circular mesh pieces</td>
			<td></td>
			<td></td>
			<td>Can be cut from (e.g.) a 600 mm long, 6 mm x 18 gauge wire mesh (e.g. galvanized steel gutter guard)</td>
		</tr>
		<tr>
			<td>Schedule 40 PVC pipe &#8211; 96 mm ID / 114 mm OD</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Schedule 40 PVC pipe &#8211; 73 mm ID / 89 mm OD</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Schedule 40 PVC pipe &#8211; 63 mm ID / 73 mm OD, OR 6 - 73 mm plastic shower drains</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Schedule 40 PVC pipe &#8211; 25 mm ID</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>6 - 6 mm thick x 155 mm square sheets of PVC</td>
			<td></td>
			<td></td>
			<td>Can purchase 2 &#8211; 6 mm x 300 mm (appx) sheets for about $20 each from: https://www.interstateplastics.com/Pvc-Gray-Sheet-PVCGE~~SH.php?vid=20180212222911-7p</td>
		</tr>
		<tr>
			<td>6 &#8211; 140 mm by 19 mm plastic funnels</td>
			<td></td>
			<td></td>
			<td>To direct water flowing from soil sample into collection beaker</td>
		</tr>
		<tr>
			<td>Adhesive caulk</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>1 &#8211; length of 150 mm x 1200 mm wire mesh cloth</td>
			<td></td>
			<td></td>
			<td>4 Mesh works well</td>
		</tr>
		<tr>
			<td>2 &#8211; 120 mm x 1219 mm plastic gutter with end caps</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>4 &#8211; gutter hangers</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>1 - additional gutter end cap</td>
			<td></td>
			<td></td>
			<td>To be cut as described in procedures to create a constant head in the supply gutter</td>
		</tr>
		<tr>
			<td>1 &#8211; large plastic tub</td>
			<td></td>
			<td></td>
			<td>Appx 65 L in volume, for example, to serve as water source for the hydraulic conductivity procedure</td>
		</tr>
		<tr>
			<td>1 &#8211; large plastic tub</td>
			<td></td>
			<td></td>
			<td>To serve for wetting up soil samples</td>
		</tr>
		<tr>
			<td>1 &#8211; Submersible pump</td>
			<td></td>
			<td></td>
			<td>e.g. Beckett M400 AUL or M400 AS</td>
		</tr>
		<tr>
			<td>Plastic tubing</td>
			<td></td>
			<td></td>
			<td>Various sized drainage tubes, water supply tube, and drain from drainage gutter</td>
		</tr>
		<tr>
			<td>Container of Cheese Cloth</td>
			<td></td>
			<td></td>
			<td>To place at bottom of soil sample help retain soil in plastic sample container during hydraulic conductivity and wetting up</td>
		</tr>
		<tr>
			<td>Rubber bands</td>
			<td></td>
			<td></td>
			<td>Large enough to fit around plastic sample liners tightly</td>
		</tr>
		<tr>
			<td>Scale which measures to at least 0.1 gram</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Beaker or other container to collect water from each sample</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Chloride</td>
			<td></td>
			<td></td>
			<td>For creating a water quality similar to that which is typically applied to the soil</td>
		</tr>
		<tr>
			<td>Calcium Chloride</td>
			<td></td>
			<td></td>
			<td>For creating a water quality similar to that which is typically applied to the soil</td>
		</tr>
	</tbody>
</table>

wastewater irrigation impacts on soil hydraulic conductivity: coupled field sampling and laboratory determination of saturated hydraulic conductivity

自二十世纪六十年代代初以来, 宾夕法尼亚州立大学进行了一项替代性废水排放实践研究, 并对其影响进行了监测。污水被用于由大学管理的森林和耕地, 而不是将处理过的废水排放到溪流中, 从而直接影响水流质量。在考虑废水回用时, 与土壤水力电导率降低有关的问题。本手稿中描述的方法是, 将土壤样本大小与实验室的水力电导率测量仪的大小相匹配, 提供了相对快速的样品收集和控制的好处。实验室边界条件。结果表明, 污水回用对土壤在 depressional 地区深层输送水的能力有一定的影响。大部分的土壤水力电导率的下降似乎与收集样品的深度有关, 并通过推断, 与土壤结构和质地的差异有关。

为了探讨污水在活滤网中的应用是否影响了土壤输送水的能力, 我们进行了试验, 以测量土壤的饱和水力电导率。我们比较了土壤的水力电导率与现场的非灌溉区的灌溉面积。废水对土壤水力电导率的影响是一个令人关注的问题, 因为有些报告指出, 在较潮湿的地区, 土壤输送水的能力减少 (例如) 土壤中钠的积聚或从表面生物外壳的发展。对于收集的用于水力电导率测量的?...

Watch this Scientific Journal Video about Wastewater Irrigation Impacts on Soil Hydraulic Conductivity: Coupled Field Sampling and Laboratory Determination of Saturated Hydraulic Conductivity at JoVE.

Wastewater Irrigation Impacts on Soil Hydraulic Conductivity: Coupled Field Sampling and Laboratory Determination of Saturated Hydraulic Conductivity

污水灌溉对土壤水力电导率的影响: 耦合场取样与饱和水力电导率的实验室测定

在这里, 我们提出了一个方法, 匹配的土壤样本大小和水力电导率测量装置, 以防止所谓的墙上流动沿土壤容器内被错误地包括在水流测量。它的使用表明, 从污水灌溉网站收集的样本。

Since the early 1960s, an alternative wastewater discharge practice at The Pennsylvania State University has been researched and its impacts monitored. ...

wastewater-irrigation-impacts-on-soil-hydraulic-conductivity-coupled

Research

JoVE Journal

Environment

9.1K 次观看.  Pennsylvania State University. 在这里, 我们提出了一个方法, 匹配的土壤样本大小和水力电导率测量装置, 以防止所谓的墙上流动沿土壤容器内被错误地包括在水流测量。它的使用表明, 从污水灌溉网站收集的样本。

视频: Wastewater Irrigation Impacts on Soil Hydraulic Conductivity: Coupled Field Sampling and Laboratory Determination of Saturated Hydraulic Conductivity

Design and Operation of a Continuous 13C and 15N Labeling Chamber for Uniform or Differential, Metabolic and Structural, Plant Isotope Labeling

Tracing rare stable isotopes from plant material through the ecosystem provides the most sensitive information about ecosystem processes; from CO2 fluxes and soil organic matter formation to small-scale stable-isotope biomarker probing. Coupling multiple stable isotopes such as 13C with 15N, 18O or&#160;2H has the potential to reveal even more information about complex stoichiometric relationships during biogeochemical transformations. Isotope labeled plant material has been used in various studies of litter decomposition and soil organic matter formation1-4. From these and other studies, however, it has become apparent that structural components of plant material behave differently than metabolic components (i.e. leachable low molecular weight compounds) in terms of microbial utilization and long-term carbon storage5-7. The ability to study structural and metabolic components separately provides a powerful new tool for advancing the forefront of ecosystem biogeochemical studies. Here we describe a method for producing 13C and 15N labeled plant material that is either uniformly labeled throughout the plant or differentially labeled in structural and metabolic plant components.
Here, we present the construction and operation of a continuous 13C and 15N labeling chamber that can be modified to meet various research needs. Uniformly labeled plant material is produced by continuous labeling from seedling to harvest, while differential labeling is achieved by removing the growing plants from the chamber weeks prior to harvest. Representative results from growing Andropogon gerardii Kaw demonstrate the system&#39;s ability to efficiently label plant material at the targeted levels. Through this method we have produced plant material with a 4.4 atom%13C and 6.7 atom%15N uniform plant label, or material that is differentially labeled by up to 1.29 atom%13C and 0.56 atom%15N in its metabolic and structural components (hot water extractable and hot water residual components, respectively). Challenges lie in maintaining proper temperature, humidity, CO2 concentration,&#160;and light levels in an airtight 13C-CO2 atmosphere for successful plant production. This chamber description represents a useful research tool to effectively produce uniformly or differentially multi-isotope labeled plant material for use in experiments on ecosystem biogeochemical cycling.

Design and Operation of a Continuous 13C and 15N Labeling Chamber for Uniform or Differential, Metabolic and Structural, Plant Isotope Labeling

This method explains how to build and operate a continuous 13C and 15N isotope labeling chamber for uniform or differential plant tissue labeling. Representative results from metabolic and structural labeling of Andropogon gerardii are discussed.

设计一个连续和操作<sup&gt; 13</sup&gt; C和<sup&gt; 15</sup&gt;Ñ贴标商会统一或差分，代谢和结构，植物同位素标记

Tracing rare stable isotopes from plant material through the ecosystem provides the most sensitive information about ecosystem processes; from CO2 fluxes ...

科研

环境科学

Integrated Field Lysimetry and Porewater Sampling for Evaluation of Chemical Mobility in Soils and Established Vegetation

Potentially toxic chemicals are routinely applied to land to meet growing demands on waste management and food production, but the fate of these chemicals is often not well understood. Here we demonstrate an integrated field lysimetry and porewater sampling method for evaluating the mobility of chemicals applied to soils and established vegetation. Lysimeters, open columns made of metal or plastic, are driven into bareground or vegetated soils. Porewater samplers, which are commercially available and use vacuum to collect percolating soil water, are installed at predetermined depths within the lysimeters. At prearranged times following chemical application to experimental plots, porewater is collected, and lysimeters, containing soil and vegetation, are exhumed. By analyzing chemical concentrations in the lysimeter soil, vegetation, and porewater, downward leaching rates, soil retention capacities, and plant uptake for the chemical of interest may be quantified. Because field lysimetry and porewater sampling are conducted under natural environmental conditions and with minimal soil disturbance, derived results project real-case scenarios and provide valuable information for chemical management. As chemicals are increasingly applied to land worldwide, the described techniques may be utilized to determine whether applied chemicals pose adverse effects to human health or the environment.

Field lysimetry and porewater sampling allow researchers to evaluate the fate of chemicals applied to soils and established vegetation. The goal of this protocol is to demonstrate how to install required instrumentation and collect samples for chemical analysis during integrated field lysimetry and porewater sampling experiments.

综合外地Lysimetry和孔隙水采样的化学活动性土壤的评价和植被成立

Potentially toxic chemicals are routinely applied to land to meet growing demands on waste management and food production, but the fate of these chemicals ...

Soil Sampling and Isolation of Entomopathogenic Nematodes (Steinernematidae, Heterorhabditidae)

Entomopathogenic nematodes (a.k.a. EPN) represent a group of soil-inhabiting nematodes that parasitize a wide range of insects. These nematodes belong to two families: Steinernematidae and Heterorhabditidae. Until now, more than 70 species have been described in the Steinernematidae and there are about 20 species in the Heterorhabditidae. The nematodes have a mutualistic partnership with Enterobacteriaceae bacteria and together they act as a potent insecticidal complex that kills a wide range of insect species.
Herein, we focus on the most common techniques considered for collecting EPN from soil. The second part of this presentation focuses on the insect-baiting technique, a widely used approach for the isolation of EPN from soil samples, and the modified White trap technique which is used for the recovery of these nematodes from infected insects. These methods and techniques are key steps for the successful establishment of EPN cultures in the laboratory and also form the basis for other bioassays that consider these nematodes as model organisms for research in other biological disciplines. The techniques shown in this presentation correspond to those performed and/or designed by members of S. P. Stock laboratory as well as those described by various authors.

Soil Sampling and Isolation of Entomopathogenic Nematodes Steinernematidae, Heterorhabditidae

Entomopathogenic nematodes are soil-inhabiting roundworms that parasitize a wide range of insects. We demonstrate sampling methods used for the isolation of these nematodes from the soil using two techniques: the insect baiting and the modified White trap, for the recovery of nematodes from soil samples and infected insect cadavers, respectively.

土壤采样及昆虫病原线虫的分离（Steine​​rnematidae，异小）

Entomopathogenic nematodes (a.k.a. EPN) represent a group of soil-inhabiting nematodes that parasitize a wide range of insects. These nematodes belong to ...

A CO2 Concentration Gradient Facility for Testing CO2 Enrichment and Soil Effects on Grassland Ecosystem Function

Continuing increases in atmospheric carbon dioxide concentrations (CA) mandate techniques for examining impacts on terrestrial ecosystems. Most experiments examine only two or a few levels of CA concentration and a single soil type, but if CA can be varied as a gradient from subambient to superambient concentrations on multiple soils, we can discern whether past ecosystem responses may continue linearly in the future and whether responses may vary across the landscape. The Lysimeter Carbon Dioxide Gradient Facility applies a 250 to 500 &#181;l L-1 CA gradient to Blackland prairie plant communities established on lysimeters containing clay, silty clay, and sandy soils. The gradient is created as photosynthesis by vegetation enclosed in in temperature-controlled chambers progressively depletes carbon dioxide from air flowing directionally through the chambers. Maintaining proper air flow rate, adequate photosynthetic capacity, and temperature control are critical to overcome the main limitations of the system, which are declining photosynthetic rates and increased water stress during summer. The facility is an economical alternative to other techniques of CA enrichment, successfully discerns the shape of ecosystem responses to subambient to superambient CA enrichment, and can be adapted to test for interactions of carbon dioxide with other greenhouse gases such as methane or ozone.

A CO2 Concentration Gradient Facility for Testing CO2 Enrichment and Soil Effects on Grassland Ecosystem Function

The Lysimeter Carbon Dioxide Gradient Facility creates a 250 to 500 &#181;l L-1 linear carbon dioxide gradient in temperature-controlled chambers housing grassland plant communities on clay, silty clay, and sandy soil monoliths. The facility is used to determine how past and future carbon dioxide levels affect grassland carbon cycling.

一个外线<sub&gt; 2</sub&gt;浓度梯度用于测试CO<sub&gt; 2</sub&gt;浓度与土壤对草地生态系统功能的影响

Continuing increases in atmospheric carbon dioxide concentrations (CA) mandate techniques for examining impacts on terrestrial ecosystems. Most ...

Soil Lysimeter Excavation for Coupled Hydrological, Geochemical, and Microbiological Investigations

Studying co-evolution of hydrological and biogeochemical processes in the subsurface of natural landscapes can enhance the understanding of coupled Earth-system processes. Such knowledge is imperative in improving predictions of hydro-biogeochemical cycles, especially under climate change scenarios. We present an experimental method, designed to capture sub-surface heterogeneity of an initially homogeneous soil system. This method is based on destructive sampling of a soil lysimeter designed to simulate a small-scale hillslope. A weighing lysimeter of one cubic meter capacity was divided into sections (voxels) and was excavated layer-by-layer, with sub samples being collected from each voxel. The excavation procedure was aimed at detecting the incipient heterogeneity of the system by focusing on the spatial assessment of hydrological, geochemical, and microbiological properties of the soil. Representative results of a few physicochemical variables tested show the development of heterogeneity. Additional work to test interactions between hydrological, geochemical, and microbiological signatures is planned to interpret the observed patterns. Our study also demonstrates the possibility of carrying out similar excavations in order to observe and quantify different aspects of soil-development under varying environmental conditions and scale.

This study presents an excavation method for investigating subsurface hydrological, geochemical, and microbiological heterogeneity of a soil lysimeter. The lysimeter simulates an artificial hillslope which was initially under homogeneous condition and had been subjected to approximately 5,000 mm of water over eight cycles of irrigation in an 18-month period.

土壤蒸渗仪开挖加之水文，地球化学和微生物调查

Studying co-evolution of hydrological and biogeochemical processes in the subsurface of natural landscapes can enhance the understanding of coupled ...

Protocol for Microplastics Sampling on the Sea Surface and Sample Analysis

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of scientific publications address microplastic pollution of the sea surface. The protocol below describes the methodology for sampling, sample preparation, separation and chemical identification of microplastic particles. A manta net fixed on an &#187;A frame&#171; attached to the side of the vessel was used for sampling. Microplastic particles caught in the cod end of the net were separated from samples by visual identification and use of stereomicroscopes. Particles were analyzed for their size using an image analysis program and for their chemical structure using ATR-FTIR and micro FTIR spectroscopy. The described protocol is in line with recommendations for microplastics monitoring published by the Marine Strategy Framework Directive (MSFD) Technical Subgroup on Marine Litter. This written protocol with video guide will support the work of researchers that deal with microplastics monitoring all over the world.

The protocol below describes the methodology for: microplastics sampling on the sea surface, separation of microplastic and chemical identification of particles. This protocol is in line with the recommendations for microplastics monitoring published by the MSFD Technical Subgroup on Marine Litter.

协议塑料微粒采样的海面和样品分析

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of ...

Evaluating Dryocosmus Kuriphilus-induced Damage on Castanea Sativa

Dryocosmus kuriphilus Yasumatsu has become a major pest for Castaneasativa since its arrival in Europe. Its galling activity results in the formation of different gall types and prevents the development of normal shoots. Repeated and uncontrolled attacks cause, besides the production of galls and the attendant gall-related reduction in leaf area, progressive corruption of the branch architecture, including the death of branch parts, and an increase in dormant bud activation. Thus far, there have been few attempts to quantify branch architecture damage. Further, the different methods for assessing infestation degree (MAID) that have been developed focus only on the galls' presence and abundance.
Using the leaf area to sapwood area relationship as a green biomass indicator, we developed in a previous study a damage composite index (DCI) that takes into account the most important branch architectural features, allowing for realistic damage assessment during the entire epidemic process. 
The aim of this study is to present this novel method and highlight differences in the damage description with respect to other broadly used indices. Results show how the DCI depicts branch damage better, especially during the epidemic peak, compared to MAID, which tend to underestimate it. We conclude by suggesting how to properly evaluate the overall impact of the pest by means of our composite damage index, the infestation degree using classic methods, and crown transparency evaluations.

Evaluating Dryocosmus Kuriphilus-induced Damage on Castanea Sativa

It is common practice to assess the damage caused by Dryocosmus kuriphilus by considering the abundance of galls alone rather than by also taking related branch corruption into consideration. We propose a composite damage index that takes into account the most important branch features, thus enabling more realistic damage assessment.

栗瘿栗瘿致锥害的评价

Dryocosmus kuriphilus Yasumatsu has become a major pest for Castaneasativa since its arrival in Europe. Its galling activity results in the formation of ...

Laboratory and Field Protocol for Estimating Sheet Erosion Rates from Dendrogeomorphology

Sheet erosion is among the crucial drivers of soil degradation. Erosion is controlled by environmental factors and human activities, which often lead to severe environmental impacts. The understanding of sheet erosion is, consequently, a worldwide issue with implications for both environment and economies. However, the knowledge on how erosion evolves in space and time is still limited, as well as its effects on the environment. Below, we explain a new dendrogeomorphological protocol for deriving eroded soil thickness (Ex) by acquiring accurate microtopographic data using both terrestrial laser scanning (TLS) and microtopographic profile gauges. Additionally, standard dendrogeomorphic procedures, dependent on anatomical variations in root rings, are utilized to establish the timing of exposure. Both TLS and microtopographic profile gauges are used to obtain ground surface pro&#64257;les, from which Ex is estimated after the threshold distance (TD) is determined, i.e., the distance between the root and the sediment knickpoint, which allows de&#64257;ning the lowering of the ground surface caused by sheet erosion. For each profile, we measured the height between the topside of the root and a virtual plane tangential to the ground surface. In this way, we intended to avoid small-scale impacts of soil deformation, which may be due to pressures exerted by the root system, or by the arrangement of exposed roots. This may provoke small amounts of soil sedimentation or erosion depending on how they physically affect the surface runoff. We demonstrate that an adequate microtopographic characterization of exposed roots and their associated ground surface is very valuable to obtain accurate erosion rates. This finding could be utilized to develop the best management practices designed to eventually halt or perhaps, at least, lessen soil erosion, so that more sustainable management policies can be put into practice.

Characterizing erosion from dendrogeomorphology has usually focused on accurately finding the starting time of root exposure, by examining macroscopic or cell level changes caused by exposure. Here, we offer a detailed description of different novel techniques to obtain more precise erosion rates from highly accurate microtopographic data.

利用树形地貌估算板材侵蚀速率的实验室和现场协议

Sheet erosion is among the crucial drivers of soil degradation. Erosion is controlled by environmental factors and human activities, which often lead to ...

Sampling for Estimating Frankliniella Species Flower Thrips and Orius Species Predators in Field Experiments

The western flower thrips, Frankliniella occidentalis (Pergande), is a polyphagous pest that has been spread worldwide. The extensive use of insecticides in attempts to control its populations eliminates natural enemies and competitor flower thrips species, thereby increasing its populations. An unsustainable situation develops with concomitant resistant pest populations, secondary pest outbreaks, and environmental degradation. Integrated pest management utilizes knowledge of pest and natural enemy relationships to implement tactics that are environmentally friendly and sustainable. Minute pirate bugs are the most important worldwide predators of thrips. They can suppress and ultimately control Frankliniella species flower thrips. Flower samples taken at least weekly are needed to understand predator-prey dynamics. Shown here is the sampling of the flowers of fruiting vegetables and companion plants to estimate the densities of individual thrips and minute pirate bug species. Representative data illustrates how the protocol is used to determine the efficacy of management tactics over time and how to evaluate the benefits of predation by minute pirate bugs. The sampling protocol is similarly adaptable to sampling thrips and minute pirate bugs in other plant species hosts.

Sampling for Estimating Frankliniella Species Flower Thrips and Orius Species Predators in Field Experiments

Presented here is a protocol to determine the number of thrips and minute pirate bug predators in crops over multiple dates in field experiments. Also illustrated is how to determine the efficacy of management tactics against thrips and evaluate the benefits of predation by minute pirate bugs.

现场实验中估计富兰克林菌种花纹和奥里乌斯物种捕食者的取样

The western flower thrips, Frankliniella occidentalis (Pergande), is a polyphagous pest that has been spread worldwide. The extensive use of insecticides ...

Measuring Phosphorus Release in Laboratory Microcosms for Water Quality Assessment

Phosphorus (P) is a critical limiting nutrient in agroecosystems requiring careful management to reduce transport risk to aquatic environments. Routine laboratory measures of P bioavailability are based on chemical extractions performed on dried samples under oxidizing conditions. While useful, these tests are limited with respect to characterizing P release under prolonged water saturation. Labile orthophosphate bound to oxidized iron and other metals can rapidly desorb to solution in reducing environments, increasing P mobilization risk to surface runoff and groundwater. To better quantify P desorption potential and mobility during extended saturation, a laboratory microcosm method was developed based on repeated sampling of porewater and overlying floodwater over time. The method is useful for quantifying P release potential from soils and sediments varying in physicochemical properties and can improve site-specific P mitigation efforts by better characterizing P release risk in hydrologically active areas. Advantages of the method include its ability to simulate in situ dynamics, simplicity, low cost, and flexibility.

Accurate quantification of phosphorus (P) desorption potential in saturated soils and sediments is important for P modeling and transport mitigation efforts. To better account for in situ soil-water redox dynamics and P mobilization under prolonged saturation, a simple approach was developed based on repeated sampling of laboratory microcosms.

测量实验室微量微生物中的磷释放,用于水质评估

Phosphorus (P) is a critical limiting nutrient in agroecosystems requiring careful management to reduce transport risk to aquatic environments. Routine ...