Network ecology paper - Education and Training Encyclopedia

Network ecology paper

Author Li Chenyang

Starting from the University of Oklahoma, it takes more than half an hour to drive to the endless grassland. In 2009, Zhou Jizhong, a professor at the University of Oklahoma in the United States, built an experimental station here to collect soil samples every year to detect microorganisms, forming a long-term sequence study.

On February 23rd, Zhou Jizhong's research team published a paper in Nature-Climate Change, saying that climate warming can make the microbial ecological network in soil more stable. This seems to be good news-but researchers say the problem is not that simple.

The weather is getting hotter and hotter, and the microorganisms are getting stronger and stronger.

The impact of climate change is extensive and far-reaching. There have been many studies on how global warming affects the survival of animals, plants and humans. But what about microbes? In this regard, people's understanding is still relatively lacking.

"This is largely due to lack of technology." The paper * * * and the first author, Guo Xue, an assistant researcher in Tsinghua University, told China Science Journal, "Since 20 10, metagenome technology has gradually matured, and people have an effective method to study microbial communities."

When Zhou concentrated on establishing the experimental station in 2009, he realized that this technology would develop and expand in the next few years. He knew it was time to chronicle the soil microbes here.

The researchers set up 24 artificial warming plots and 24 normal temperature plots as control. The heated sample is continuously heated by an infrared lamp. During the five-year period from 20 10 to 20 14, the soil temperature in the warming plot continued to rise, and they studied the changes of microbial ecological network in soil samples year by year.

"Ecological network refers to the complex relationship between organisms in a certain environment, including predation, parasitism, competition and * * * life." The paper * * * and the first author, Yuan, a postdoctoral fellow at the University of California, Berkeley, explained to the China Science Journal, "As for microorganisms, we can't directly observe their complex interactions in function, so we innovatively use data simulation to build an interaction network between microbial species."

So how will temperature affect the complexity and stability of microbial ecological network? Before the research, the researchers had two hypotheses: on the one hand, according to the theory of metabolic ecology, organisms grow faster and more active at higher temperatures, and the interaction between them will be closer, thus speculating that warming will increase the complexity of species combination and make the ecological network more stable; On the other hand, according to people's understanding of climate warming, warming will have a destructive impact on some species, so the microbial ecological network may also weaken or even collapse.

After five years of continuous research and analysis, they found that the microbial ecological network on the heated samples became more complex and stable than that of the control group.

"According to our usual understanding, climate warming is reducing biodiversity and destroying the stability and function of ecosystems. However, this study shows that at least the soil microorganisms here show strong buffering and adaptability in the face of environmental changes, which may have a certain positive effect on maintaining the function of grassland ecosystem. " Zhou Ji said.

Invisible "flora" is promising.

From the human point of view, microorganisms seem to be natural "supporting roles", and we seldom realize how great these countless and invisible little creatures are playing.

However, microbial ecology, which has accelerated in recent years, believes that microorganisms may be powerful "colonies" that we need to rely on when dealing with various "side effects" of global warming.

A review article published in the journal Science in 2020 pointed out that the frequency and duration of drought are increasing in many parts of the world, and the existence of root microorganisms can greatly improve the resistance of plants to drought and help increase crop yield. The author suggests: "It is necessary for us to combine ecology with plant, microorganism and molecular methods, which is the key to make crop production more suitable for the future climate."

"Protecting the interaction between microorganisms may be very important for reducing biodiversity loss and ecosystem function damage caused by climate warming." Zhou Jizhong said, "In fact, scientists now have some methods, such as adding beneficial microorganisms to the soil to improve the growth rate and resistance of plants to offset the reduction in production caused by climate change."

Are we too worried about climate warming?

"In a warmer world, the related ecosystem functions may not be so fragile," wrote Zhou Jizhong's team paper.

This seems to be an optimistic conclusion. Are we too worried about the impact of global warming on life on earth?

The researchers said that this problem is more complicated than expected. First of all, we should see that this is only a regional positioning experiment, and to what extent it is applicable to other ecosystems needs more research.

A paper published in the Biology of Global Change not long ago pointed out that under the conditions of climate warming and drought, microorganisms in the bottom soil of alpine grassland in Qinghai-Tibet Plateau become "lazy and inefficient"-their functions as "decomposers" and "contributors" are obviously reduced.

"It is interesting to read these two papers together." Yuan said, "The areas we studied (the Central Plains of the United States and the Qinghai-Tibet Plateau) have different research objects (surface soil microorganisms and bottom soil microorganisms), different research focuses (microbial ecological networks and microbial functions), and the conclusions of microbial responses to climate warming are also quite different. This shows that this is a very complicated research field, and we know very little about it. "

"What impressed me most about this study is that microorganisms have strong adaptability." Guo Xue said, "In fact, the climate of the earth has been changing, and there will always be some creatures that can adapt to the new environment and eventually form new biological communities."

In the sample land that they studied, the vegetation is constantly evolving, and more and more plants adapt to the high temperature. Moles like to dig holes and build nests here more and more. In 20 18, they discovered a cactus for the first time. At the same time, the work of experimenters has become more and more hard, and the frequency of heatstroke has become higher and higher.

"Again, the earth doesn't need to be saved, but human beings need to save themselves." Guo Xue said, "Even microbes are trying to adapt to climate change, and we humans should take action and actively respond."