Download Influence of agriculture on water quality

Ministry of Education of the Republic of Belarus
BELORUSSIAN STATE UNIVERSITY OF TRANSPORT
Ecology and management of water resources chair
REPORT
“The influence of agriculture on water quality”
Done by:
Supervisor:
Yelaha Hanna, Chaly Yaroslau, Hromava Kseniya
Novikova O.
students of group SV-21
Gomel, 2009
Content
The influence of agriculture on water quality
1. The development of agriculture and its impact.
2. The problem of water allocation.
3. The problem of agriculture on water quality and the environment.
3.1 Deforestation.
3.2 WATER POLLUTION.
3.3. WATER MELIORATION
3.4 Drainage of lands.
Introduction
The problem of the influence of industry and agriculture on the environment is global in nature,
that led to its importance. In recent years the social problems of environmental protection
purchased in highly developed countries to the priorities of profit. At the industry and other
branches of the economy is putting pressure on the part of society and state. This stimulates
the search for highly efficient and cheap means of solving problems of environment protection,
development of new technologies, the reorientation of agricultural and industrial enterprises in
low-waste cycles.
The influence of agriculture on water quality
1. The development of agriculture and its impact
Intensive agriculture has a significant impact on the environment, which manifests itself
mainly in the form of negative externalities. Growth of plowing land, increasing the number of
tractors and agricultural machinery, the introduction of large quantities of organic and mineral
fertilizers, application of plant protection products, resulting in contamination of soil, water and
air are harmful components, chemicals, exhaust fumes.
The main elements in the system of environmental management of agriculture are land,
water, forest resources, as well as minerals. In the unity of living organisms (plants, animals,
microorganisms), climate, topography, air, they form ecological-economic system. It formed the
necessary conditions for production to meet the needs of society. Today's agriculture
significantly disrupted the natural ecological system and helped create an artificial
environment. Input resources of agriculture - the energy and chemicals - are derived from nonrenewable, draw from natural resources such as oil and natural gas.
The activities of agriculture includes the use of some farms pesticide tsidov (for example,
spraying chemicals, sprays may damage crop neighboring farms), the use of nitrogen fertilizers
(eg, when the result is a water-pollution, which is used by other households), or deforestation,
which may, for example, to raise water tables and salinization of surrounding soils. As a result,
such lands can grow only the most salt-tolerant culture. Cutting trees can lead to increased
salinity of rivers to such an extent that they can not be used for irrigation and drinking water for
livestock.
In areas with significant rainfall destruction of natural vegetation from agricultural activities
usually leads to a strong outflow of water. In such cases, the floodplains of the rivers more
likely to occur floods (floods), which Origin of go-not only after heavy rains, but also because of
the erosive rainfall (deposits), which contributed to rapid erosion along river banks. The growth
of such flooding has negatively influence on the economy, located in the lower reaches of rivers
where the soil and sand become infertile as a result of increased salt erosion.
2. The problem of water allocation.
In some cases, in agriculture, there are quite a direct adverse impact of natural resources, as in
the case of common ownership of water resources. Imagine that the river water used to irrigate
a few farms. If his demand for water exceeds the available supply, there is a problem of
distribution. If you do not control the economy, below the river, will receive the amount of
water is less necessary. Consequently, the cost of a product produced using water for irrigationment, for farms downstream river will be higher than for farms located you Hsi downstream. Ie
amount of water is not distributed so as to maximize the value of its contribution to
production. In this case, the total amount of water should be the distribution but to equate the
marginal product of all water users must submit a limited amount of water for households in
the upper part of the river, and for households in the bottom of a river. The problem of
allocation of water resources is particularly acute for artificial irrigation systems associated with
the construction of canals and culverts long.
Policies to redress the situation may include:
1. Imposing water users Taxes assessed on each unit of water;
2. Sale of rights to use the total available water;
3. Introduction of market quotas for water use.
In practice, non-transferable quotas are often used by European governments for the allocation
of rights to use water. This practice is not always effective with the economic viewpoint,
because quotas are rarely distributed in such a way as to equalize the value of marginal product
obtained by all users of water.
On the other hand, taxes and the establishment of water market may also not be optimal. Onthe logs must be installed if the water demand or the available quantity of water has changed,
and this requires a flexible assessment and forecasts.
Since water is an important and necessary natural resource for the growing population and
economy, is worth considering other agriculture-related problem The use of water. Consider
groundwater or water supply. This is an important water-HYDRATED resource for agriculture
and other areas. The nature of these waters is different to, and therefore considered an
example here is a special case. If the groundwater readily available, their use is unlikely to be
effective in terms of economy.
The cost of pumping or access to the underground water basin can not be the same for all
those involved in agriculture. With an increase in the uncontrolled pumping, groundwater
levels may fall, and they will not be available in areas where underground pools are shallow.
Sometimes, this may be areas that use water more efficiently, or the cost of its delivery to the
surface below. The policy of free access to water is not only cost per unit of water will increase,
but also the average cost (value) of production, using water will decrease.
3. The problem of agriculture on water quality and the environment.
Since agriculture can adversely affect itself, it can negatively affect other sectors of the
economy and social interests. For example, the allocation of nitrates from fertilizers used in
agriculture or animal manure can contaminate surface or ground water used by man for
drinking, affect the quality of water used for technical purposes, to promote the growth of
weeds in the rivers ("strangle" them and increase water loss) and, in some cases, affect the
navigation, and increase the entropy of ponds and lakes.
Destruction of natural vegetation to agriculture can make a landscape less attractive to
travelers and tourists, although it is not always the case. Considerable variability of water level
in rivers due to the destruction of natural vegetation, which may negatively affect the
availability of potable water for urban areas, enhance seasonal water shortage in urban areas
and increase the frequency of urban flooding. Most water turbidity reduces the fish
populations, lowers the number of tourists, but in areas where near the mouths of rivers grow
corals, may lead to their destruction, as during the floods dirty river water is conveyed far out
to sea. The accumulation of silt in the harbor and waterways increases the cost of navigation.
Increasing floods flooded roads, which has caused great damage. This list can be continued. It
also includes the loss of wild species of the destruction of their habitats. In the past, the use in
agriculture of some poisons, such as DDT, was incorrigibly in the sense of destroying wildlife.
The livestock sector is a significant consumer of water, accounting for the total agricultural
water withdrawals account for about 70 km3 per year.
The most negative aspect of the impact of livestock on the landscape - the pollution of natural
water run-off of livestock farms. Repeated in elevated concentrations of organic substances in
freshwaters, and then in the coastal marine area significantly reduces the oxygen in the water,
leads to a change in the community aquatic organisms, in-struction in food chains can cause
fish kills and other effects.
The dramatic changes in the environment of rural areas Obu-slovleny fact that the area of land
changing flows of matter, is being solid, liquid and dissolved runoff. Deforestation increases soil
erosion, solid runoff of rivers, leading to siltation of riverbeds, reservoirs, floodplain arrays.
Stream flow in the forest area to 10% decrease on average by 5%. Active migration of elements
on the slopes, their rapid entry into reservoirs, while reducing runoff causes severe pollution of
surface waters. This pollution can be toxic, because such dangerous elements such as cadmium,
mercury, strontium, lead, zinc, are the most mobile in most soil types.
Due to urbanization organic waste are lost to agriculture and cities which are discharged into
the water.
3.1 Deforestation
As a result of such an effect on wildlife, increasing control of agriculture and its development. In
some countries and states have restrictions on the of variation of habitats of plants and animals
on the farm. For example, deforestation may be prohibited or permitted only when a special
environmentally-court weigh all the pros and cons of such environmental changes. Regulating
felling of trees is especially important, because the patched their destruction adversely affects a
whole on the environ-ment and the impact on the survival of individual species. Cutting trees
leads to an increase in erosion, more runoff water, and hence flooding and other hydrological
effects in the lower reaches of the river, as well as the salinization of land in adjacent areas.
Cutting can be controlled by a set of alternative policy instruments.
3.2 WATER POLLUTION:
The problem of the influence of industry and agriculture on the environment is global in nature,
that led to its importance. In recent years, social task of Environmental Protection acquired in
highly developed countries priority over profit. At the industry and other branches of the
economy is under pressure from society and state. This stimulates the search for highly efficient
and cheap means of solving problems of environment protection, development of new
technologies, the reorientation of agricultural and industrial enterprises in low-waste cycles.
Untreated waste water in agricultural production are a source of water pollution. Wastewater
carry hazardous chemicals, pathogens, insecticides and herbicides, nutrient-HN constituent of
fertilizers.
This issue causes concern for the health and lives. Although the natural environment is already
so seriously infected that completely eliminate pollution has become impossible.
Pesticides and fertilizers used in agriculture, are washed into rivers, lakes, seas with rain water
and become food for bacteria. This bacteria theory consume the oxygen dissolved in water,
resulting in fish and aquatic animals begin to suffocate. In some places, raw sewage is washed
into rivers and seas and cause illness and sometimes death, in both animals and humans.
3.3. WATER MELIORATION
Water reclamation of old troubled souls. Irrigation canals were built by the ancient Egyptians,
seeing a way to improve soil fertility.
Water Reclamation (Irrigation and drainage) - one of the main ways a way of enhancing
productivity of agricultural land, occupying 10% of the world's land area. The sixth part of the
land reclaimed, and they receive 40 to 50% of the total production of agricultural products.
Reclamation of land is a necessity in the transformation of natural systems, transformation of
swamps and wetlands in the prime agricultural lands, social and economic transformation of
the country. As an important link intensification of agricultural production improvement is
expected to make a tangible contribution to the Food Programme.
For the irrigation of natural complexes removed the huge mass of water. In many countries
and regions of the world's irrigation was the main water flow in dry years led to a shortage of
water resources. Water consumption in agriculture is among all kinds of water the first place
and is over 2000 km 3 / year, or 70% of global water consumption, of which more than 1500
km3 - consumptive use of water, of which 80% goes to irrigation.
3.4 Drainage of lands.
The huge square in the world occupy the wetlands, the use of which is possible only after the
drainage activities. Drainage provides a very serious impact on the landscape. Especially highly
variable thermal balance territories - are significantly reduced costs of heat by evaporation,
decreases the relative humidity, increasing the amplitude of diurnal temperature range.
Changing air regime of soils, increasing their permeability, respectively, changing the course of
soil formation processes (actively decomposing organic litter, an enrichment of the soil pitatelnymi substances). Drying also causes an increase in groundwater depth, and this, in turn,
can cause dehydration numerous streams and even small rivers. A very serious global
implications of drainage - the swamp give the bulk of atmospheric oxygen.
In summary, we can conclude that agriculture is on the one hand caused significant ecological
damage, and on the other - the potential benefits of wildlife conservation and maintenance of
organ systems. Therefore, it is central to the economy, the environment.
Sustainable economic development and the maintenance of species diversity - are the main
issues for the conservation of the environment. The value of agricultural systems for the
stability of agricultural productivity and its effect on species diversity allows us to understand
the concept of sustainable development.