[July 28th,2015] – Learning the Importance of GPS and How to Survey Diversity on a Variety of Terrains – (Team Dryad’s Saddle)

[July 28th,2015] – Learning the Importance of GPS and How to Survey Diversity on a Variety of Terrains – (Team Dryad’s Saddle)

Blog Entry Written by Team: Dryad’s Saddle

Team Members: Derek James Newton (Queen’s), QIN Lanxue (Tongji), XING Kangnan (BNU), LYU Wenyang (d’Overbroecks)

Weather: Sunny, Temp:20~32℃

Day 2- As we all wearily woke up early on this Tuesday morning, our group embarked on a birding expedition. We first made a quick stop to see an artificial grey rat snake (Pantherophis spiloides) nest built by some of the ecologists here at QUBS as a nesting site for these oviparous reptiles. These snakes are endangered in Ontario due to habitat fragmentation, so QUBS provided a nest site designed to mimic the piles of decomposing vegetation or compost they usually to lay eggs in; the decomposition of the organic matter warms the eggs. This is important for proper incubation and embryo development.  We soon came across a calling pine warbler (Setophaga pinus), one of the New World finches (Parulidae). Many black-capped chickadees (Poecile atricapillus) chirped and a sharp “chick-chick” call from the sexually dimorphic species called the downy woodpecker (Dryobates pubescens) was heard in the forest. We knew we still had a while to go to get to Cow Island Marsh, because these species are terrestrial, not wetland-associated. Soon we saw some bright and territorial yellow-throated warblers (Setophaga dominica), and blue jays (Cyanocitta cristata) calling. We walked over the boardwalk in the marsh and heard the “prehistoric caw” of the great blue heron (Ardea herodias), and saw a Caspian tern (Hydroprogne caspia) fly over, but these organisms inhabit lakes. However,we did not find true wetland species until the swamp sparrow (Melospiza georgiana) popped up in the bullrush and Typha and we knew we had finally arrived at Cow Island marsh.

In the rest of the morning, we were discussing the seminar topics in groups. In order to be fully prepared for the activities in the afternoon, we warmed up by giving a presentation in groups.In the afternoon, Qu mingzhi was giving us a lecture about the fundamental principles of GPS and how we use it. Here is a quick summary about that.

GPS is used in many things such as boats, planes, telephones.  Three important segments make up GPS—— the Space segment, the Ground segment and the User segment.However, GPS is not the only position system in the world. There is Galileo Positioning System (Galileo) in Europe, Global Navigation Satellite System (GLONASS) in Russia and Beidou Navigation System (COMPASS) in China.

Geographic Coordinate System was created to be a common language to describe an accurate position worldwide. The advantage is that GCS works anywhere in the world but the data shown on the screen is not a linear unit and it can not be used to measure distance. So we use Projected Coordinate System to make it more accurate. Projected Coordinate System is defined on a flat, two-dimensional surface, has constant magnitudes, angles, and areas across the two dimensions.

However, one of the most used coordinate systems is UTM (Universal Transverse Mercator). It divides the Earth between 80°S and 84°N latitude into 60 zones, 6°of longitude in width. Data shows the location of us is in 18T (UTM Zone No.) 3925000 (Easting Value) 4936000 (Northing Value). The measuring unit is always in meters.

Three important functions in a GPS device are waypoint, trace back, and geotagged photographs. GPS can provide you your current position, displaying a time of past positions and storing them, storing a large number of known locations, giving your real-time estimates on your travel progress. It’s better than smart phones because it always has a strong signal and is better adaptable to temperature (from about -40℃ to 60℃). There’s no need to connect Internet, it’s waterproof and easy to carry with several AA batteries. We learned that you should always mark the home location before going out and never drop your map or compass.

We visited an upland marsh in the afternoon that was surprisingly dry, as most of the water was hidden underground and all surface moisture had evaporated in the heat. The high ground near the road was covered with the brilliant yellow of goldernrod (Solidago canadensis). The grass and sedges that covered the uplands make this upland marsh a great habitat for rails (Rallidae) to navigate because of their long feet. A few butterflies and dragonflies flew by as we walked deeper in the marsh, but willow trees (Salix) and cattails (Typha) dominated the lower, moister soil. We learned of alpha, beta, and gamma diversity, and their usefulness in assessing wetland health.

After supper, Wenxi gave us a very interesting lecture on eDNA which is environmental DNA. Without isolating target species we can extract DNA from the environmental samples such as soil, water, etc by using some new techniques. eDNA has a lot of advantages such as high sensitivity. Even if a deer only drops by on the lakeside to drink water, it is possible to detect the deer’s DNA in the sample of water. The studies are focusing on several fields, such as invasive species detection, conservation monitoring, technique improvement and natural history reconstruction. It is very important to detect invasive species sooner than later because waiting causes complications as the invasive species begin to overpopulate .To start, you need to go to the wetland to take water samples of the eDNA study first, followed by water sample collection, then DNA extraction, and in the end is conventional/quantitative PCR. A lot of challenges are still being presented in this field, but it has drawn more and more attention around the world. This lecture really interests me because I think that a lot of problems do exist in the world waitng to be solved and in eDNA will be a very useful tool to deal with environmental issues when the technique get highly developed.

It was a great day and we all learnt more about the bird species and be familiar with each other. We also learnt a lot about GPS and eDNA. Although it was a tiring day, it was worth it.

[2015年7月28日] 学习GPS重要性和使用及如何在不同地域调查多样性(树神之鞍小队)

今天早上大家都起得很早,我们带着倦意踏上了第二次观鸟之旅。首先,我们停下来观察一个灰鼠蛇(Pantherophis spiloides)的人工巢,这个巢是由QUBS的生态学家为这种卵生爬行动物而修建的。在安大略省,由于这是濒危物种且生境破碎,它们通常会在巣中堆肥并将卵产在里面,所以QUBS模仿建造了人工巢址。这些肥料层在阳光照射下会发热,有机物分解产生的热量对于胚胎发育和鸟蛋孵化有着至关重要的影响。很快,我们就被松鸣鸟(Setophaga pinus)的声音所吸引,它是新世界雀(Parulidae)的一种。同时黑头山雀(Poecile atricapillus)也在啁啾而鸣;还有绒毛啄木鸟(Dryobates pubescens)也在森林里叽叽喳喳地尖叫,这是一个容易分辨雌雄的物种。

这些品种都是在陆地栖息而非水生的,所以想必我们距离牛岛的湿地还有一段距离。不久之后我们听到一些领土黄喉莺(Setophaga dominica)和蓝鸟(Cyanocitta cristata)在歌唱。我们走过架在沼泽上的浮桥,听到了大蓝鹭(Ardea herodias)独特的歌声,仿佛一瞬间将我们拉回远古时代,转眼又见一只红嘴巨鸥(Hydroprogne capasia)飞过来。但在这些生物栖息的湖泊上,我们没有找到真正的湿地物种,直到沼泽麻雀(Melospiza georgiana)突然出现在芦苇和香蒲中,我们才终于来到了牛岛湿地。晚上我们观看了电影《观鸟大年》,惭愧的是我们远远比不上电影中的观鸟人那样狂热,而幸运的是我们没有像在电影中一样,在偏远的阿留申群岛上嬉戏,而是被开饭的铃声叫了回去。

上午大家以组为单位对演讲的内容进行讨论,吃过午饭,我们以组为单位简单的介绍了自己,既更了解了大家,又为下午的活动热身,一举两得。

下午我们的助教屈铭志给我们上了一堂生动有趣的课,讲了很多关于GPS的知识,内容摘要如下:

GPS几乎无处不在,例如船只、飞机和智能手机等。主要由三个部分,分别为太空发射装置、地面接收装置和客户端。然而,GPS并不是世界上唯一的卫星定位系统。在欧洲有伽利略卫星定位系统,在俄罗斯有格洛纳斯卫星定位系统,在中国有北斗卫星定位系统。

在世界范围内需要一种用来精确描述位置的通用语言,这就是地理坐标系(GCS)。GCS的优点是可以涵盖地球表面的每一个点。但缺点是它是非线性的,所以不能用来计算距离。因此作为一种改进,我们现在使用的是投影坐标(PCS)。投影坐标在一个二维平面内有固定的长度、角度和面积。然而应用最广泛的坐标系统是墨卡托方位法(UTM)。这个系统将地球自南纬80°至北纬84°之间的部分分为60个区,每个区的宽度为6°经度。数据以例如18T 3925000 4936000的方式呈现。并且测量单位均为米。

GPS最重要的三个功能是标记地点,导航和形成有地理标记的图像。GPS能够提供实时地理位置,显示并储存历史等大量信息,提供路况信息。相比与智能手机它的信号更好,且在-40℃到60℃范围内皆可使用。使用时不需要联网,防水性好,便于携带。需要注意的是,在出发前要标记出发地点,并随身携带地图和指南针。

下午,我们前往一片地势较高的湿地,令人惊讶的是这里显得非常干燥,因为大部分水都藏在地下,而地表的水分在阳光的照射下几乎都蒸发了。这片高地临近公路的部分长满了好看的“加拿大一枝黄花”(Solidago canadensis)。因为这里被大量的野草和花丛覆盖,所以对秧鸟来说是良好的栖息地,它们长长的脚掌使它们能够在湿地上畅行。不同于长在高地的植物,柳树和香蒲长在更低更潮湿的环境中。当我们向湿地深处走去,几只蝴蝶和蜻蜓从我们身边悄悄飞过。顶着炎炎烈日,我们还认真学习了α多样性、β多样性和γ多样性,这对于湿地生态健康评估有很大的用处。

吃过晚饭,冯文熙给我们上了一堂非常有趣的讲座,是关于eDNA的。“e”代表了“环境”(environmental)。通过使用一些新技术可以从一些环境样本中提取DNA,例如土壤中,水中等,而不用直接接触要研究的目标物种,便可以分析出目标物种的基因序列。eDNA有很多优势,其中一项就是高敏感度。即便是一只小鹿来到湖边喝水,那么在取到的湖水样本中或许就能检测出小鹿的DNA。现在eDNA的研究主要集中在几个领域,如入侵物种检测,保护监测,技术改进和。实时监测入侵物种是十分有必要的,因为在一个新的环境中,当入侵物种开始扩张时再进行处理有一些晚,处理起来会很麻烦并且耗费太大。在进行一项eDNA研究之初,我们需要到湿地中(或是特定环境中)进行调查,随后采水样,再在提取DNA后进行PCR等操作。这个领域目前依然面对着很多挑战,但是也受到了越来越多的重视和注意力。我对这个讲座非常感兴趣,因为目前世界上的确存在很多问题亟待解决,日后eDNA新技术发展的更加纯熟后,将会是用来解决环境问题的得利工具。

一天下来大家都感觉非常疲惫但是都感觉这样做是值得的,我们收获了友谊和知识,真是充实又有趣的一天。

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