Qiang (Marvin) Yang, Author at EcoEvo@TCD

14/02/201914/02/2019

Looking beyond mean trends of environmental change

During my first week in Dublin, Ireland, I was more shocked by the countless sunny-rainy shifts within one single day than its natural beauty, although I had been warned of its fickle weather in advance. That was something totally new to me. Born and raised in a small inland town in North China, I had grown accustomed to taking for granted that a whole sunny day could be prophesised by bright morning sunlight through the window. Then I started to imagine that, if fitting a curve to the weather, the curve of my birth village would surely be much smoother than Dublin, even though the former has four much more distinct seasons. But, at that moment, I had neither realized that this thought actually reflected the difference in the temporal autocorrelation of environmental conditions in the two places nor how this could be linked to the dynamics and stability of ecosystems.

Read Marvin’s full post on the Nature Ecology & Evolution blog.

This post is based on the paper Yang et al. (2019) ‘The predictability of ecological stability in a noisy world.’ Nature Ecology & Evolution

Header photo by Brocken Inaglory on Wikimedia Commons (CC BY-SA 3.0)

11/05/201514/02/2019

Before training your dragon, print a 3D tail for him

3D printing (or additive manufacturing, AM) describes any of the various processes used to make a three-dimensional object. In 3D printing, additive processes are used, in which successive layers of material are laid down under computer control. While its limitless potential in manufacturing, the construction industry, transportation and human health has been widely recognized, 3D printing also plays a significant role in animal protection and conservation.

Several cases of using 3D printing for animal assistance have been reported during the past few years. Although artificial limbs have been used to help poor dogs and other animals who lost their legs, 3D printing makes the design and manufacture of the limbs far easier. And, thanks to the well developed 3D-scanning technology, the printed limbs are more efficient and comfortable for animals. Just see how happy this dog is.

Birds also benefit from 3D printing. This bald eagle and Costa Rican toucan both received printed beaks which will hopefully improve their chances of survival. And a tortoise has even been given a new shell thanks to 3D printing technology.

3D printing can be also applied to animal conservation in the wild. For example, the Wildlife Conservation UAV Challenge uses 3D printed drones to save endangered animals from poachers. 3D printing has also been used to build animal habitats including hives for bees, artificial reefs for fish, and nests for birds.

For the sake of scientific education, 3D printed models of skulls, organs and muscles can be used for demonstrations and detailed observations. In research, the technology can play an important role in studies of animal behavior and physical ecology. For example, 3D printed birds and fish can be used to explore how animals adapt to hydraulic resistance.

The wide-ranging potential for using 3D printing in animal protection and conservation seems limitless!

Author: Qiang Yang (Marvin), @MarvinQiangYang

Image Source

03/10/201414/02/2019

Sustainability Through Stability

I recently took part in a Tansley working group, an initiative that has a main working theme of advancing the ecological foundations of sustainability science. In this specific case we are seeking to construct a unified framework to help understand the multidimensional stability of ecosystems.

In an era of increased human activity, significant climate change and biodiversity loss, an understanding of the mechanisms and drivers of ecosystem stability has vast implications for both ecological theory and the management of natural resources.

One large challenge in the study of ecological stability comes from the complexity of ecosystems. The dynamics of an ecosystem depend not only on the network structure, the interactions among different species, but also on external perturbations that vary in context, intensity and frequency.

Another huge challenge is the multidimensional nature of ecological stability, with its many measures and definitions including resistance, resilience and temporal variation, all of which are themselves interrelated. Stuart Pimm, a member of the Tansley working group, reviewed four measures of stability in one of his early publications in Science (Pimm, 1984) and one blog from Jeremy Fox even summarized 20 different stability concepts!

Both theoretical and empirical ecologists have spent decades exploring the role of community structure, interaction strength and disturbance in determining the dynamics and stability of ecosystems. However, most of these studies only focused on a single aspect of ecological stability, underestimating the impacts and recoveries of populations and communities.

Failure to consider the multidimensionality of stability is magnified when the relationships among these stability elements are quite fragile. For example, one lake or reservoir may maintain its stability in total biomass following a disturbance by adjusting its nutrient load, but the community composition has changed dramatically.

To create a unified concept of stability across theoretical, field-based and experimental research the confusion in using and defining these different elements of stability must be cleared up.

A typical confusion arises from the usage of the term resilience, which can be defined as the recovery time or speed following a disturbance to a pre-disturbed state; for instance the time taken for an area of scrubland to recover from a wild fire. The method used to calculate resilience in the local stability of theoretical communities is impossible to detect in the real world. So there is an urgent need to fill this gap by making a framework that suits both empirical scientists and theory development.

And that is one of the main challenges the Tansley working group seeks to face. We aim to construct a framework of ecological stability across major global ecosystems through a review of the most up to date measures of ecological stability (both empirical and theoretical) using specific case studies. This will help researchers adopt a more comprehensive approach to investigate stability and facilitate the comparison across different systems and scales in the future. We will also evaluate the feasibility in applying theoretical stability measurements to real ecosystems and abandon those which will are next to impossible to obtain from the real world.

To communicate the importance of the stability concept to a much broader audience, we will provide videos as well as vivid examples to illustrate the concepts of the different stability elements and how to measure them. We have an enthusiastic belief that the Tansley group will make a big contribution to the standardization of concepts and measurement of the multidimensional stability.

Author: Marvin Qiang, qyang@tcd.ie, @MarvinQiangYang

Photo credit: http://www.changedbygrace.net/2012/09/21/faith-floods-and-finances/