понедельник, 25 июля 2016 г.

The role of agrosystems in air pollution: satellite technologies suggest a solution


Recently the issue of environmental pollution and of its consequence such as global warming has been highly discussed at different levels from mass media to heads of governments. United Nations conference on climate change which took place in Dec, 2015 in Paris, France obliged countries that use hydrocarbon fuels to decrease emission of greenhouse gases to the atmosphere, and this fact correlates with world economics looking toward implementation of use of renewable fuels. However this process is unacceptable and almost impossible for many countries at the moment. It goes without saying for such countries as Saudi Arabia, Venezuela and India, and even in the USA this decision of the Paris climate summit found its opponents. The denial of vital questions of climate change and global warming is similar to practice of "burying the heads in the sand." These issues do exist and take their toll on world economy not in the best way.

But why are those who are actively concerned about environmental pollution so entirely focused on the issue of hydrocarbon fuels? One can say that emission of greenhouse gases to the atmosphere is only one of several global factors. You would not guess but such sphere of economics as agriculture affects negatively environmental pollution also. In its turn it is agriculture that primarily experiences losses from the effects of climate change. Exceptional weather phenomena (e.g. droughts and heat waves) are often related with air pollution, and all that causes drastic losses of productivity in agriculture. Food safety is the key issue for the society in this century.

According to modern researches, evaporation of fertilizers and animal waste which are rich in nitrogen combines in the air with emissions from fuel combustion and thus aerosols are formed, which can be a major factor of illness and death. These aerosols surpass all other human sources of pollution of fine-grained air on majority of the territories of the USA, Europe, Russia and China. Eventually the excess of fertilizers comes into streams and rivers. Agricultural pollution comes to the atmosphere mainly in the form of ammonia which is released into the air as gas from excessively fertilized fields and animal waste. Then this compound mixes with pollutants from combustion which are generally nitrogen oxides and sulfates oxides produced by vehicles, power plants and industrial processes. Aerosols can penetrate deeply into lungs of living creatures, causing heart or lung disease. The prospects of transition of world energetics to renewable energy sources can seem more than vague, but the control of amount of used fertilizers without affecting crop productivity is more than real. Nowadays the use of fertilizers is a technological process which is far ahead from principle of “the more you fertilize, the more crop you get”. Technologies of fertilizing are designed for each specific agricultural plant, for original weather conditions in a region, for different stages of plant growth, for actual weather, for presence of pests, etc. For proper use of technologies of fertilizing there exist powerful analysis tools providing feedback and accurate evaluation of efficiency of the use of fertilizers on each field. Analysis of weather data allows evaluation and forecast of such characteristics as humidity, precipitation, solar radiation (UV-index).

With the help of satellite communications it is possible to estimate condition of fields, plant growth rate (NDVI-index), while weather history serves to get to know reasons of what is happening. At the moment there are products that let farmers control 100ha fields remotely. Thus modern technologies are here not only to relieve farmers’ work, but also to provide proper control over fertilizers used and by this to decrease environmental pollution.