Are we messing up with the nature?

The answer to both is yes. Engineers can develop green (which will be the next engineering wave) to help limit/reverse the impact man has made. Also working in balance knowing when to say "stop". We need lots of pristine natural areas left alone as well.

well our environment was most suffered in 19th century,in fact watever was developed in 20th century wasnt doing much harm to the nature,well measures are taken to conserve natural resources and environmant but until common man is aware of its danger and consequences we can make little change,but we sure eliminate materials/devices harmfull for environment

a) Engines, from which the word engineering was derived, mostly pollute air.
b) Elecronic waste which is nondecomposible and in huge mass causes pollution.
c) Disposal of biomedical waste is one of the problems faced.
d) Air-conditioners, coolers, refrigerators and similar categories exhaust hazardous gases and dengerous refrigerents.
e) Energy generation sets that run on fossil fuels emit harmful gases.

That is a great topic to explore and debate! I would think it is actually the other way around. The 19th cenury would mainly have high carbon emmissions from coal and wood fires, metals. Although polluting, I think the myriad of exotic pollutants of our current society which includes stuff like mercury, radioactive materials, complex chemicals & gases, plastics, is much more damaging not only in volume but the fact they take much longer for the planet to naturally degrade. I bet one launch of a NASA space shuttle kicks out way more pollutants than several 19th century factories combined over a long time period. How fascinating a study on this would be as I could be way wrong!

sauravgoswamiwell our environment was most suffered in 19th century,in fact watever was developed in 20th century wasnt doing much harm to the nature,well measures are taken to conserve natural resources and environmant but until common man is aware of its danger and consequences we can make little change,but we sure eliminate materials/devices harmfull for environment

Big time. Progress and advancement of human race in general has come at a cost. And it is a hefty price we are paying, so much so that it is threatening our very existence. There are some efforts sure to revert back the changes but I wonder will they ever be enough. All the comforts of our modern life are of no use, if the simple air we breathe is polluted and is no more life sustaining. Just this simple example goes a long way to shake us up to know how much we take the environment around us for granted.
Human imprint on nature's resources is so vast and great that it dubbed as a beginning of an entire new epoch called The Anthropocene which begins when human activities started to have a significant global impact on Earth's ecosystems.
It is just a choice and a vital question of how far are we willing to go for our progress and at what cost?!