Agro - environmental management and practice

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Chapter 20
Agro - environmental management and practice
Main content
20.1 Agricultural ecological environmental
problems and its harm
20.2 Agro - environmental management and
practice
20.3 Ecological agriculture
20.4 Modern intensive sustainable agriculture
20.5 Case study
20.1 Agricultural ecological environmental problems and its harm
20.1.1 Environmental problems of agricultural production
Figure 20-1 Schematic diagram of common agricultural environmental problems and its harm
(1) Pesticide pollution
Migration, proliferation, residues, aggregation behavior
will pollute the atmosphere, water and soil and is harmful
to the organisms
The organisms accumulate gradually in vivo by the
food chain,which make the top of the food chain
organisms (including humans) with higher pesticide
content in vivo
It makes ecosystems lose their balance, cause the
system’s structure variation and function decline, and loss
biodiversity.
Figure 20-2 The cycle of pesticide in the environment (Li and Fleck, 1972)
①
Organochlorine pesticides
Chlorinated aromatic derivatives,including BHC, Dieldrin,and
DDT etc.
Stable structure,difficult to be oxidized, difficult to be
dissociated ,high toxic, easy to be dissociated in organic solvents,
particularly in adipose tissue, and is high efficient, high toxic,and high
pesticide residue
It accumulates in the organisms’ fat and liver by the food chain in a
large number, harms the nerve center,casues liver enzyme changing,
has pathological changes by violating the kidney, and the toxicity is
difficult to degrade.
It has been forbidden to use since 1983, but the accumulation of
pesticides in the past, will continue to play a role in quite a long time
② Organophosphorus pesticide
Most containing phosphorus organic compounds are phosphate
or amides, such as DDVP, 1605, malathion and kitazine etc.
Highly toxic, easy to break down,the time of residue in the
environment is short,not easy to accumulate in plants and
animals,so it is often considered safe pesticides
But it’s high toxicity to humans and animals,it can inhibit the
acetylcholine esterase, lipase and serine proteases aliphatic in the
body to disrupt normal nerve function, causing disorders of
biochemical processes in vivo with the symptoms as vomiting,
diarrhea, fecal incontinence and blood pressure rising, eventually
leading to death. Therefore, its environment toxicity still can not be
ignored.
③
Carbamate pesticides
With phenyl-N-alkyl ester’s structure, the same as organic
phosphorus pesticides,they all have a role in anti-cholinesterase, the
same in poisoning symptoms, but there are differences in the
mechanism
 It is easy to decompose in the natural environment, and can be
metabolized rapidly in vivo. Usually the metabolites have more
toxicity than their own, and are low-residue pesticides.
Some species have acute toxicity, such as furadan, its oral LD50
is 8-14mg/Kg,and it is a high toxic pesticide
This kind of pesticides may have the potential to cause
carcinoma and teratogenesis.
(2) Fertilizer pollution
It play a considerable role in agricultural production, but if
applying improperly it may be seriously cause the impact and
harm to the soil, air, water, agricultural products, and the
whole ecosystem.
Ecosystem pollution is a multi-media environment pollution
and contaminants in various environment media have physical,
chemical and biological processes.So the pollutants in multimedia environment demonstrate relevance, transferability and
cycle. (figure 20-3)
Figure 20-3 Migration transformation rule of chemical fertilizer nutrient element in the environment
①
Nitrogen fertilizer pollution
Figure 20-4 Nitrogen fertilizer pollution brings environmental problems
②
Phosphate fertilizer pollution
Phosphate fertilizer is not to be volatiled and weted.It has
less effect to the atmospheric and ground water. However,it
usually contains a variety of heavy metal and has potential
impact to the soil and crops.
In our phosphate rock, the amount of its fluoride
containing is basically proportional to the phosphate
containing, resulting increasing the fluoride content in the
soil
Phosphate fertilizer also contains trace amounts of
natural radioactive elements. Especially in surrounding of
the phosphate rock, there is a potential danger of radioactive
pollution,and it is also polluting the environment
in
production process, transportation, and the trial process.
③ Potassium fertilizer and
microelement fertilizer pollution
With the development of agricultural production, potash
fertilizer and trace fertilizer are used widely. But if it is used
improperly,it may still harm to the environment
It may easy to destroy soil structure resulting in soil
compaction,if improper use of potassium sulfate;It may
accumulate the chloride ion in the soil, destroy soil structure, and
reduce the quality and yield of some crops ,if potassium chloride
is used improperly.
Excessive trace elements could easily pollute the soil poisoning
the crops, affecting the yield and quality
(3) Poultry excrement pollution
Large -scale livestock breeding base takes great pollution to the
environment
According to the statistics,the amount of livestock manure is
more than 2.5 billion ton in China in year 2000,and is much more
than the total national industrial solid waster
Take a sample of the Hangzhou Bay,which has the most
pollution in Yangtze River region. Its pollution is mainly caused by
agricultural pollution,especially pesticides, fertilizers and poultry
excrement pollution.
Research shows that poultry excrement is the main renson
which causing the pollution indicators of Hangzhou Bay exceeding
the standard seriously.(see table20-1) At the same time, the
pollution proportion is trending to increase(see table 20-2).
Table 20-1 The proportion of main sources of pollution indicators of Hangzhou Bay in
year 1994(unit
:%)
pollution
source
livestock
manure
agriculture
fertilizers
industrial
pollution
domestic
pollutant
inorganic
nitrogen
35
40
5
10
10
total
phosphoru
s
BOD
21
6
0
14
59
18
0
17
22
43
Notes:quoted from Yang Chaofei,2001
other
pollution
Table 20-2 The proportion of main sources of pollution indicators of Hangzhou Bay in year
2013
(unit :%)
pollution
source
livestock
manure
agriculture
fertilizers
inorganic
nitrogen
49
32
total
phosphorus
29
BOD
29
industrial
pollution
domestic
pollutant
other
pollution
4
7
8
10
7
24
30
0
17
24
30
Notes:quoted from Yang Chaofei,2001
The reason of why the faeces cause the pollution is that it has
high concentrations of pollutants,and also contains large amounts
of protein nitrogen, albuminoid nitrogen ,ammonia nitrogen and
many phosphorus and a large number of pathogens (see table 20-3)
 When the faeces was directly discharged into the environment
without treatment,it may :
Pollute the soil and groundwater
Pollute the surface water, even the drinking water and
endangering human health
Stench pollution of the livestock’s faeces
Table 20-3 Physical and chemical properties of livestock wastes
Item
cattle
manure
bovine
urine
pig
manure
pig urine
chicken
manure
Moisture (%)
86.2
94.2
70.5
95.5
77.5
pH
7.0
8.3
7.2
8.0
6.36
7.0~9.0
suspended
matter (ppm)
119000
5000
223000
4500
132800
22000~26
000
BOD(ppm)
24000
3900
62000
5000
65400
800015000
COD(ppm)
19600
5997
35030
9297
45000
total nitrogen
(ppm)
9430
8344
4664
7780
14600
5000~
6000
ammonia
nitrogen (ppm)
2086
320
426
1082
1150
3000~
4000
Notes:quoted from Chen Weixin,1993
human
excrement
s
(4) Biological pollution
① Biology invasion
The harm caused by biology invasion to the agricultural
ecological environment and natural resources damage is
irreversible,and it accelerates biodiversity loss and species
extinction
Once the success alien species invasion, it will be very difficult
to eradicate, and it will be expensive to control the damage.
The direct economy loss caused by biological invasion is 122.6
billion U.S. dollars annually in America.
The economy loss caused by several main invasive species is
54.7 billion Yuan per year,in China
②
Transgenic organism
As unnatural evolution products, it has been
widely disputed for its potential impact in human
health and ecological environment safety since the
success of recombinant DNA technology.
Some experts believe that transgene crops or its
wild relatives species can be changed to "super"
weeds; may cause gene escape, resulting in "super
virus"; danger to biological diversity; may
adversely affect to human health
20.1.2 Agro-ecosystems damage
(1) The reduction of biodiversity
On one hand ,agricultural production activities such
as farming, the use of pesticide and fertilizer and
plant and animal genetic improvement in agriculture
improves the productivity ,on the other hand it also
impacts the biological diversity in agricultural
ecosystems. Figure 20-5 shows the components and
functions of biological diversity in agricultural
ecosystems
Figure 20-5 Component and function of biodiversity in agro-ecosystems
Notes:quoted from Chenxin,etc ,2002
(2) Soil degradation
It is a phenomena and process,which the soil environment
quality and carrying ability decline rapidly caused by human’s
improper development and utilization in natural environment.
 In the early stage of reclamation soil, it only destroys the
balance of the natural vegetation and fertility of the soil and the
vegetation can also be restored by abandonment of cultivated
land and the fertility can be restored by use organic manure.
But overuse of soil may cause the soil erosion, desertification,
salinization, swampiness and soil fertility decline and other soil
degradation phenomenon . Figure 20-6 is the classification of
soil degradation
Figure 20-6 Classification pattern of soil degradation
(quoted from Li Tianjie,1995)
20.2 Agro - environmental management and practice
20.2.1 Agricultural environmental management system
(1)
Agricultural environmental management agency
Our national first-level environment division is Environment
Protection Energy department of agriculture ministry.Meanwhile
Agriculture Ministry sets up Environment Protection Committee
to organize and coordinate environmental protection work in
various sectors of agriculture.The corresponding environment
management institution has also been set up in the agricultural
sector of each province, autonomous region and municipality.
(2) Agricultural environmental
management object
Figure 20-7 Agricultural environmental management object
20.2.2 Agricultural environmental management approach
Figure 20-8 The classification of agricultural environmental management measures
20.2.3 Agricultural environmental
management policy
(1) Environment management in the constructing process in small town
① industrialization makes agriculture lose the resources in process of urbanization
 land occupation
 the loss of high-quality workforce
 the of resources
②
The environment problem in small town construction
Table 20-4 The environment problem in small town construction
Main problem
Production
problem
Live problem
Cause
Occupy land in large number
Abuse arable land, unreasonable land
planning ,large waste of land resources
Serious pollution of township
form
High energy consumption, high pollution,
increasing emissions, as the main
pollution source of small town
Ecological damage
Many unreasonable conduct in
construction, resulting in the rapid decay
of natural resources even to depletion
Serious water pollution
Lack appropriate sewage disposal system,
poor infrastructure
Solid waste pollution
No facility for garbage to pile up
③ Environment measures to
small towns construction
Adhere to balance the construction and ecological
protection, enlarge environment planning for the small
town
Adhere to innovate in Intermediated Financing
pluralistic system, enlarge investment in small-town
environment protection
Adhere to the sustainable development strategy,
enlarge the ecological environment construction of
small town
(2) Reform of agricultural production mode
Agricultural industrialization is the new reform of agricultural production mode
figure 20-9 The agricultural production mode change meaning to the environment
20.3 Ecological agriculture
20.3.1 Basic principles of Chinese eco-agriculture construction
20.3.2 Technology type of ecological agriculture
Figure 20-10 Mulberry-Dyke-Fish-Pond—Schematic diagram of water and land exchange production
systems
(quoted from the State Environmental Protection Administration ,Chinese Eco-Agriculture ,1991
20.3.3 Typical technology and environmental
protection
(1) Main techniques and environment effects of material cycles in ecological agricul
system
Figure20-11 Main practical technology and environmental benefits
(2) In-system matter cycle process
Figure 20-12 Cycle model of Guquan ecological farm
( quoted from the State Environmental Protection Administration ,1991 )
(3)
Ecological agricultural system and environment of
circular use of materials

Biogas is central link of system energy conversion, material
recycling and comprehensive utilization of organic fertilizers, is the
tie combining the primary producers, primary consumers and
decomposers
As the figure 20-13a,the energy substance is not fully used and
just used a part of it in the agricultural cycle without biogas.
 The cycle becomes perfect and improves the utilization of
energy substance after using the biogas (see figure 20-13b).It
reduces the harm to the resource environment and is conducive to
agricultural environment protection
a.
The traditional agricultural circulation ( incomplete circulation )
b.
Virtuous circle of ecological agriculture system
Figure 20-13 Comparison figure of two agricultural circulation
(4)
Ecological agricultural system energy analysis
of circular use of materials
The energy input of natural ecosystem is maily the solar
energy.But the energy inputs of artificial ecosystem are with
many additional energy beside the solar energy which is
named as artificial energy
 Agro-ecosystem is an artificial ecosystem,it can determine
whether high yield and stability, and can find the problem in
certain places and certain aspects to adopt effective measures
by the analysis of energy input-output.
Figure 20-14 Input/output of material circular ecological agriculture system energy
20.4 Modern intensive sustainable agriculture
20.4.1 The concept and aim of modern intensive sustainable
agriculture
 Definition: an acceptable mode of agricultural production operation
which adopts the base methods to maintain the natural resource, ensures
the people of present and future generations to meet the demand for
agricultural products by technology and mechanisms transform ,
maintains the land, water, plant and animal genetic resources,and will not
cause environment degradation.Its technology is appropriate,and also
feasible in economy point.
 Aim: Resource intensivism
Production modernization
Management industrialization
20.5 Case study
The construction of Dazu eco-agriculture demonstration zones
Dazu County locates in southeast of Sichuan Basin,and west of
Chongqing City
 Survey and zoning work of agricultural resources have been taking in
Dazu County from 1980 -1982 ,and there were serious problems in
agriculture ecological environment: the forest cover reduces to 320,000 mu
in 1987 from the 1190,000 mu in early 1950’s ,and the soil erosion is serious,
the loss area achieving ​40.2% of the whole county covers area.
In view of this serious situation, " the overall planning of eco-agriculture
for south-north Mountain of Dazu County,."was completed in May 1984
Figure 20-15 Geographical diagram of Dazu(map of Chongqing)
Figure 20-16 The content of ecological agriculture construction in Dazu
(1) Ecological benefits analysis
① The ecological benefits analysis of rice-fish culture
model
 Use of resources have been improved
 Improve the soil fertility and save the amount of
fertilizer
 Beneficial to inhibit weed and pests, reducing the
use of pesticide
Figure 20-17 Material cycle and energy conversion brief chart of fishing in paddy field
② Analysis on biogas ecological
project

Dazu county is an agricultural county, and the
straw output of rice, wheat, corn, beans, sorghum and
other crops is much.The annual output of straw is
355,300 tons. It can produce 71 million m3 biogas if
fully used the straw as raw material
Figure 20-5 Analysis on typical model
Samples of
model
Financial
analysis
Environment
Economy
analysis
The main problem of
effecting the
promotion
Policy focus
Rice-fish
culture
excellent
excellent
Whether the financial
benefits can be
achieved smoothly ,it
mainly depends on
whether the output and
price of fish is stable
Maintain the
financial benefits
of the farmers
Biogas
engineering
Just so so
excellent
One-time investment is
too large and it needs
operating cost.
Farmers’s direct
financial benefit is not
high
external benefits
from the society
to the farmers
Grain for
Green Project
Poor
excellent
It requires considerable
material and labor, and
financial gain is
difficult to implement
in a short term
Encourage and
guide the farmers
to adjust mode of
operation
Thank you !
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