关于海滩最恒定的事情是它们总是在易流

分析海滩如何变化并可能在将来发生变化，这并非易事。为了做出准确的预测，研究人员需要有关复杂力量和因素的数据

The most constant thing about beaches is that they are always in flux. Wind, waves, and currents move sand around, building up shorelines in some places and eroding them elsewhere, with consequences for coastal wildlife, including birds. Analyzing how beaches change, and may change in the future, is no easy task. To make accurate predictions, researchers need data on a complicated array of forces and factors, from big-picture elements like topography and tides to the tiniest components of a coast: grains of sand.

关于海滩最持续的事情是，它们总是在不断变化。风，波浪和电流在周围移动沙子，在某些地方建立海岸线，并在其他地方侵蚀它们，并对包括鸟类在内的沿海野生动植物产生后果。分析海滩如何变化并可能在将来发生变化，这并非易事。为了做出准确的预测，研究人员需要有关复杂力量和因素的数据，从地形和潮汐等大型元素到海岸最小的组成部分：沙子的谷物。

But until recently, sand has been relatively understudied. Enter SandSnap—a collaborative project sponsored by the U.S. Army Corps of Engineers, James Madison University, and consultancy Marda Science LLC. Since 2022, the project has enlisted community scientists to build a database of beach sand across the United States, from both freshwater sites like the Great Lakes and ocean beaches. The information will support beach restoration projects, including habitat for at-risk shorebirds like Red Knots and terns

但是直到最近，沙子已经相对研究了。输入Sandsnap - 由美国陆军工程兵团，詹姆斯·麦迪逊大学和咨询公司Marda Science LLC赞助的合作项目。自2022年以来，该项目已邀请社区科学家从大湖区和海洋海滩等淡水地点建造一个在美国各地的沙滩数据库。该信息将支持海滩修复项目，包括红色结和燕鸥等高危岸边的栖息地

The SandSnap database currently contains some 2,800 analyzed images of beach sand, along with their latitude, longitude, and a measure of grain size—a crucial factor in how beaches change over time. The process is simple: Participants go to a debris-free section of dry sandy beach, place any coin on the sand for scale, snap a photo with a cell phone, and upload the image to the project's web site. Analysts measure the sand’s grain size using a deep-learning neural network trained on a range of sediment samples from diverse locations. Slightly more than 70 percent of the existing images are from U.S. beaches; the rest are from sites worldwide.

Sandsnap数据库目前包含大约2800张经过分析的沙滩图像，以及它们的纬度，经度和晶粒尺寸的度量，这是海滩随时间变化的关键因素。该过程很简单：参与者转到干沙滩的无碎屑部分，将任何硬币放在沙滩上以获取比例尺，用手机拍摄照片，然后将图像上传到项目的网站上。分析师使用在不同位置的一系列沉积物样本中训练的深度学习神经网络来测量沙子的晶粒尺寸。现有图像中有70％以上来自美国海滩；其余的来自全球的网站。

Sand comes in many sizes and shapes, reflecting the rocks and shells that produced it and the geologic processes that wore them down. “Beaches exist in a rough equilibrium between the size of the waves and the size of the sand-grains,” says David Young, an Army research engineer. The larger sand-grains are, the more energy it takes to move them, so the presence of finer sands and clays indicates that a beach has small, gentle waves. If bigger sand-grains start washing up, wave action is likely increasing. To build an accurate computer model of a shifting coastline, scientists need to know the exact size of the beach’s sand-grains. But no comprehensive database of sand-grain sizes in North America exists, and collecting this information would be prohibitively expensive for any single agency or laboratory, especially because the composition of beach sand changes over time. Since beaches are popular destinations, community scientists are well positioned to help fill the knowledge gaps.

沙子有多种尺寸和形状，反映了产生它的岩石和贝壳以及使它们磨损的地质过程。陆军研究工程师戴维·扬（David Young）说：“海滩在海浪的大小和沙粒的大小之间存在粗糙的平衡。”较大的沙粒是移动它们所需的能量，因此较细的沙子和粘土的存在表明海滩有小而柔和的海浪。如果较大的沙粒开始洗涤，波浪动作可能会增加。为了建立一个不断变化的海岸线的准确计算机模型，科学家需要知道海滩沙粒的确切尺寸。但是，北美没有全面的沙粒大小数据库，并且对于任何单个机构或实验室而言，收集此信息都会非常昂贵，尤其是因为海滩砂的组成随着时间而变化。由于海滩是受欢迎的目的地，因此社区科学家在帮助填补知识空白方面处于良好状态。

Though the Corps is best known for dredging rivers, harbors, and channels to keep ship traffic moving nationwide, the agency also restores or creates tens of thousands of acres of wetlands every year, sometimes using dredged sand to do so. “The Corps used to dump a lot of valuable dredged sediments offshore, but they’ve become better partner in reusing some of it,” says Brad Winn, vice president for resilient habitats at Manomet Conservation Sciences. Currently, the agency reuses about 30 to 35 percent of the material it dredges from waterways for so-called “beneficial purposes,” such as habitat restoration, and aims to increase that figure to 70 percent by 2030.

尽管该军团以挖沟，港口和渠道以保持船舶交通的全国移动而闻名，但该机构每年还可以恢复或创造成千上万英亩的湿地，有时使用疏gried的沙子来做到这一点。 Manom​​et保护科学弹性栖息地副总裁布拉德·温恩（Brad Winn）说：“过去的军团曾经在海上倾倒许多有价值的疏es矿石，但它们在重新利用其中的伙伴方面已经成为更好的合作伙伴。”目前，该机构重新以所谓的“有益目的”（例如栖息地恢复）重新挖出水道挖出的材料的30％至35％，并旨在到2030年将这一数字提高到70％。

But to meet that goal, federal engineers need more information about sand sizes and types at specific locations. Dredged material can’t be dumped randomly on the shore. “The sand needs to match the sand on the beach in size and color,” Young says. If the sand size and composition doesn’t match what’s already present, dredged material can wash away or change the profile of the beach—and that could harm shorebird species that rely on the habitat to nest or to feed during migration. Intertidal shoals, zones exposed at low tide and underwater at high tide, are “a grocery store for species like plovers, oystercatchers and migratory sandpipers,” Winn says. Foraging shorebirds pluck invertebrates from wet sands and small fish from tidal pools. On dry beaches, birds find insects and marine organisms trapped in seaweed at the wrack line.

但是为了实现这一目标，联邦工程师需要有关特定位置的沙子尺寸和类型的更多信息。挖土的材料不能随机倒在岸上。扬说：“沙子需要与海滩上的沙子相匹配。”如果沙子尺寸和成分与已经存在的材料不符，则挖土的材料可以洗净或改变海滩的轮廓，并可能损害依靠栖息地筑巢或在迁移过程中喂食的栖息地物种。温恩说，潮间带，在潮汐低潮和水下暴露的区域是“杂货店的杂货店，适用于诸如plovers，牡蛎捕捞者和候选人的杂货店”。从湿沙和潮汐池中的小鱼中觅食的鸟鸟无脊椎动物。在干燥的海滩上，鸟类发现昆虫和海洋生物被困在毛皮线上的海藻中。

In recent years the Corps has used dredged sand and mud to restore or create bird habitat in locations around the country, from Cape May County, New Jersey, to Hampton Roads, Virginia, and Savannah, Georgia. Environmentalists would like to see this work expand. “Sea level rise, erosion of dry sand beaches, and loss of intertidal areas are serious threats to beach-nesting and migratory birds,” Winn says.

近年来，该军团使用疏远的沙子和泥土来恢复或在全国各地的地点恢复或建立鸟类栖息地，从新泽西州开普梅县到弗吉尼亚州的汉普顿路和乔治亚州的萨凡纳。环保主义者希望看到这项工作扩大。温恩说：“海平面上升，干沙滩的侵蚀以及潮间带的损失是对海滩和候鸟的严重威胁。”

For anyone inspired to submit images, Brian McFall, an Army coastal engineer, offers some tips. Your photograph should capture an area slightly larger than a business card, with the coin in the corner. “Make sure you can see the sand-grains in your image, and that they aren’t blurry,” McFall says. SandSnap data has already been included in a few

对于受到提交图像的任何人，陆军沿海工程师Brian McFall提供了一些提示。您的照片应捕获比名片略大的区域，而硬币在角落。 McFall说：“确保您可以看到图像中的沙粒，并且它们不会模糊。”少量数据已包含