An Article Summary: Climate Change Could Destroy Wild Relatives of Cereals By 2070

A future study led by John Wiens, from the University of Arizona in the US, has been examining the capability of grasses including wild relatives of staple foods such as wheat and rice which provide half of all the calories burnt up by humans, to survive from the impact of global warming, especially rapid climate change. The researchers then initiate a 2070-prediction called 'troubling implications' since they have not able to make certain statement regarding the future of world food supplies.

In point of fact, 236 grass species are able to adapt to new climatic niches, the restricted areas where they can continue to exist, thus moving them to more appropriate weather condition might be helpful. However, this option becomes improper due to the estimation that the predicted rate of climate change will be 5,000 times faster than the estimated speed at which grasses could adapt to new niches. Furthermore, limited seed dispersal due to human settlements or mountains will be other obstacles to be faced. As conclusion, John Wiens emphasizes "This has several troubling implications, for both global biodiversity and human welfare."

Hi Miss Fitri.
These below are my thoughts.

... foods such as wheat and rice.(you should place period here. You successfully create the complex sentence, but you do not make it over sine it can break your flow) which provide half (...) by humans, to survive from (...), especially THE rapid climate change. The(you are able to use "THE" because you did not yet mention previously.) researchers then initiate (...) since they have BEEN not able to make A certain statement ...

... adapt to new climatic niches, IN the restricted (...) continue to exist,. thus, moving them to more appropriate ...
... due to the estimation that the predicted PREDICTING THE rate of climate change (...) the estimated speedat which grasses could adapt to new niches(It's better if you separate) .

AsIn conclusion, John Wiens emphasizes THAT "This has several troubling ...

OVERALL, IT IS A GOOD JOB

a future study led by John Wiens from the University of Arizona in the US has been examining ...... used to provide half of the calories burning up by humans in order to survive from....

OR
a future study led by John Wiens, a professor from the University of Arizona in the US, has been examining ...... used to provide half of the calories burning up by humans in order to survive from....

it is good to compose complex structure. since you have been accustomed to produce complex ones, now you need to concern about its accuracy and easiness to understand

since they haveare not able to make certain
thus moving MOVE them to more appropriate
due to the estimation that the predicted rate of climate change will be 5,000 times faster than the estimated = ineffective sentence. too many similar words repetitively used although those are in different forms