unit 2 theoretical basis of environmental science chapter 8 ecological environment professor liu...
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Unit 2 Theoretical basis of environmental science
Chapter 8
Ecological environment
Professor Liu JinglingSchool of Environment, Beijing Normal University
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School of Environment, Beijing Normal University
JinLan environmental ecology [M]. Beijing: Higher education press, 1992, 5.
Lu Mingzhong. China's environmental ecology - The primary research on the relationship between China's population, economic and ecological environment [M].Beijing: Meteorological press, 1994.
Ge Jianxiong. The living space of future [M].Shanghai: Sanlian bookstore, 1998.
Cheng Lianxi. Environmental ecology. M]. Beijing: Higher education press, 2002
Environmental ecology---the study content of environmental ecology From the subject system, environmental science----environmental ecology The subject division of modern ecology, applied ecology---environmental
ecology It is a emerging and strong comprehensiveness subject Applied ecology theory is subject studies the internal change mechanism, of
ecosystem under the man-made disturbace, discipline and positive effect for human, seeking the recovery of damaged ecosystem, reconstruction and protection measures.
[email protected] School of Environment, Beijing Normal University
Environmental ecology is a emerging interdisciplinary subject, its content and system are in the process of gradual development, and its study content including the following aspects
（ 1 ） Reasonable utilization and protection of natural resource.
（ 2 ） The biology effect of environmental pollution.
（ 3 ） The comprehensive treatment of environmental pollution.
（ 4 ） The monitoring and detection of environmental pollution.
（ 5 ） The influence of environmental pollution on structure and function of ecosystem.
[email protected] School of Environment, Beijing Normal University
Main content
8.1 The role and status of environmental ecology.
8.2 Basic theory and principle of ecosystem.
8.3 The influence of disturbance on ecosystem.
8.4 Restoration ecology theory
8.5 Ecology system management
8.6 Case study
Questions and discussion
What do you think the most principles of ecology? Do you know the important expression of ecology for environmental science and engineering?
Please take examples what ecology theory and method are used in the process of environmental problems resolution?
8.1 The role and status of environmental ecology
8.1.1 Environmental ecology
In order to provide new ideas for the ecology damage and
environmental problem, it studies the problems such as
change mechanism, discipline and restoration measure of
damaged ecosystem.
8.1.2 Study content
The feedback effect of ecosystem internal change mechanism
on human disturbance, the science seeking ecosystem
restoration, reconstruction and protective measure.
A B
C D
Figure 8-1 Ecological environmental degradation caused by human disturbace
The water loss and soil erosion of loess plateau accounts for 38% the land square
of China
The original beautiful Ke Er Bi grassland
has become the largest desert of
China
The excessive forestation trees in Taihang Mountain
results in quick extinction of animal
and plant
The excessive grazing of yak in the
source of Changjiang River
results in the degradation of
vegetation.
8.2 The theory of ecological system
8.2.1 Ecosystem
It was firstly proposed by England ecologist: A.G.Tansley in 1935.
Definition: the uniform unity that formed by gradual progressing material
circulation and energy flotation that all the biology lived in certain space
are.
Function: biology generation, material circulation and information
transmission
Structure is the basis of function, structure and function is mutually co-
exists, restricted and transformed.
The inherent quality: feedback(such as self-control)
The development and extension of concept
R.L.Lindeman（ 1950 ） When human are studying the ecosystem of lakes, they are
inspired by the sayings of Great trees keep down the little ones, proposing the conception of food chain. And he proposes ecological pyramid theory inspired by sayings that one mountain can not survive two tigers.
Fosberg(1963) There is one or more biology organism and environment composing
the system with function and interaction, including its space relations, nature characteristic, habitat and ecological niche, its organism and storage, input, output and behavior.
Poluni and Woethington（ 1990） proposed that eco-compound was mostly used in system with big effect and weak conformability.
[email protected] School of Environment, Beijing Normal University
Discussion on the concept
He Yunlong; Wang Linhe; Zhang Guosheng（ Chinese Agricultural Science Bulletin, editorial department email. the second issue of 2008
key words ： ecosystem; concept; level;subject： Discussion about the concept of ecosystem
Ecosystem has become one of the most important conceptions in ecology study, but it has different connotations due to different researchers, study object and so on, it uniformly uses definition of Tansly in expression, enables one ecosystem represent different definitions. In order to make clear the connotation and denotation of ecosystem, this article uses the form logic and set theory as the tools, combining the species relations between ecosystem and general system, it summarizes the application example of ecology and deepening analyzes conceptions such as environment, boundary and so on, so it can not clearly express study object. In the aspect of individual, population, community, landscape, biosphere, the ecosystem is not existed, they are the denotation of ecosystem, ecosystem that is ecology system, the study object of ecology is ecosystem, it can not integrate environment into e ecosystem, although ecosystem can not separate itself from environment and independently
survives. [email protected] School of Environment, Beijing Normal University
The fundamental feature of ecosystem
There are 4 main compositions in ecosystem. That is in-animates environment , producers, consumers and decomposers.（ 1） In-animates environment including: climate element, inorganic matter, organic matter.（ 2） producers It mainly means green plants; they are taking the leading role in ecosystem. （ 3） consumers Heterotrophy, mainly means various biology living on other organisms, including herbivore animals, carnivorous animals, omnivorous animals （ 4） decomposersHeterotrophy, mainly are bacterium and fungi, also including some protozoans and corrosive animals such as earthworm, termite, vulture and so on. They decompose the residual body, excrement and each complicated compound of animals and plants, absorbing decomposition product, and decompose the simple organism into simple inorganic matter, while the participation of inorganic matter into material cycling can be reused by autotrophy.
The construction and function of ecosystem
construction ： It means morphological structure (the time and space
change of species group) and nutrient structure (food chain/net, ecological niche).
function ： It means energy balance, material balance and information
transmission
types ： The classifications of natural ecosystem, classification of
compound ecosystem and classification of environmental problem.
Pattern, process and scale of landscape
pattern ： It includes unit types of landscape, trees and space
arrangement, configuration. It has equation type, random
type and aggregation type.
process ： It stresses the behavioral characteristics of ecology process,
such as species group trends, species succession, material
cycling and energy flotation, etc
scale ： When studying, the adopted time and space unit.
Figure 8-2 The level and behavior of ecosystem（ quoted from Cai Xiaoming， 2000 ）
8.2.2 Complex ecosystem theory
The level theory of ecosystem: it studies the time and space lamination structure. Level difference of high and low level: time and space, complexity, resolution ratio and
process ratio.
空间
cells organ /tissue
individual
species
community
ecosystem
landscape biosphere
grade
resolution fall
complexity
Slow behavior
process
time
8.2.3 Biodiversity
图 8-3 生物多样性是人类宝贵的财富
[email protected] 北京师范大学环境学院
Biodiversity
★ Biodiversity is refer to the biology, the ecology compound body that biology depends on as well as the total sum of diversity and variability. It is one of the most important content enables environment become diverse. ★ Biodiversity is the basic character of living system. Living system includes many aspects, from microcosmic to macroscopic; each aspect has diversity, now many studies are focus on the following:
Genetic diversity Species diversity
Ecosystem diversity
Landscape diversity
Biodiversity theory
☆ It is developing from biology evolution theory, the biology
geography of biology diverse distribution. Both are related and have the tendency to comprehensively develop into ecology theory, it provides theory basis to environmental science and engineering.
☆ It reflects the nature of geography space difference, such as circle layer, land and sea, the differentiation of land and sea. The geography commonly divides geography differentiation into zonality, regionality, regional, local, locality, and micro-zone and so on. It has provided
Questions and thinking
The value of biology diversity?! The value of ecology? The value of environment? The value of biology diversity in city? How to protect biology diversity in city?
City development and protection??
废物循环26%
固氮作用3%
生物治疗4%
作物和畜牧业5%
生物防治5%
多年生作物6%
植物抗性3%
授粉7%
海洋食物9%
生态旅游17%
其他10%
CO2螯合作用5% F
igure 8-4 The percentage of econom
y and profit provided by biology diversity to hum
an economic society. （
quoted from C
ai X
iaoming
）
Two types of value ：
Direct value: it is the biology resource and industry raw material used by human. Indirect value: important compositions that can adjust climate stabilize hydrology; protect solid, aesthetics, tourism resource. The diversity caused the stability
The diversity is irrelative to stability even positive relative
Rivet assumption: specie of ecosystem has the same important function. Redundancy assumption: the function of species is different; some species have big overlapping in ecology function.
Two views ：
Two assumptions ：
The value of biodiversity
Gree card ：the index and measure of diversity
α: the index of diversity: much and less of species in community, that is
the richness of species; the relative density of community, that is
uniformity of community. Such as
The index of specie richness, Simpson index and Shannon-Wiener index.
β: the index of specie richness: the specie succession degree according to
change of gradient environment. The little common species in different
community, the more diversity of β. Such as
Whittaker index and Cody index.
γ:diversity index: the total specie diversity of regions, it is measure by the
richness of species
8.2.4 The succession of ecosystem
Definition: As time goes by, the structure of ecosystem will also
change.
Community regularity, direction study is the argumentation focal point.
Reason of occurrence: the migration, distribution of plant vegetative form and
mobility of animals, the change between and within species, the disturbance of
human activity.
The resource ratio theory of Tilman plays an important role in explaining the
succession of ecosystem(1985).
Succession theory of ecosystem: unit climax theory, poly-climax theory and
climax-pattern hypothesis.
The resource ratio theory of Tilman thinks:
The change of resource ratio finally results in the change of
components of community species, that is resource ratio determines
the succession process of ecosystem, resource controls biology flora,
biology reversely changes its relying environmental conditions.
Including: nutrient, moisture, light consumed by biology.
Humidity and temperature are not resource.
Including: nutrient, moisture, light consumed by biology.
Humidity and temperature are not resource.
Multiple succession theory: the succession direction is determined by
nature of environmental elements, succession process exists
phenomenon multiple channels, that is succession has homoplasy and
divergence.
Unit climax theory: only climate is the determination element of
succession, others are the secondary.
Poly-climax theory: except for climate, other elements can
determine the formation of climax.
Climax-pattern: within any regions, environmental elements are
gradually changing; it will have gradient change by environmental
conditions, each specie of climax community is also successively
changing .
Figure 8-5 The succession process of plant under natural
conditions （ quoted from Cunningham,etc, 2002 ）
8.3.1 Disturbance
（ Disturbance， Perturbation and Stress ）
8.3 The theory of disturbance ecology
connotation ：
Disturbance of landscape scale means the
strongly change of landscape structure and function.
Aspect of ecology element: the discontinuously and intermediately happening elements outside community abruptly interrupts or continually exists the abnormal
fluctuation of elements, causes the obvious change of organism or specie group orcommunity, enables ecosystem damage or change the phenomenon.
types of disturbance
1. according to the motivation of disturbance
Natural disturbance Human disturbance 2. according to the resource of disturbance
Endogenous disturbance Exogenous disturbance 3. according to the property of disturbance destructive disturbance gain disturbance
It means disturbace of irresistible natural force, it is divided into physical factor (fire, hail, storm, and flood) and biological factor (the distinction of carnivorous animals, pressure relief of graminivorous animals and change in vegetation trend). The geographical area is
different and natural inference factors are also different.
Due to the disturbance formed by human production activity and other social activity produces each influence on natural environment and ecological environment.Its effect scope,
damage intensity; potential harm and induction are far surpass natural disturbance
The influence of endogenous factor on ecosystem, for example, the trees dumpage, competition between
species in forest ecosystem
Outer of system, such as strong hail, flood, storm and salvage,etc.
Human activity such as geology, climate disaster, forestation and excessive grazing for a long time
Such as reasonable felling, trimming, artificial updating, as well as lower productivity and efficiency forest transformation and so on
Ecological significance of disturbance
It is useful for disturbace effect can reduce It is useful for disturbace effect can reduce one or several superiority of some species, one or several superiority of some species,
increase resources for other species; increaseincrease resources for other species; increase the specie diversity, which is useful the specie diversity, which is useful for the natural succession of systemfor the natural succession of system
Adjustment of Adjustment of ecosystemecosystem
Elements maintaining Elements maintaining ecosystem balance and ecosystem balance and
stabilitystability
Species in the continually changeable Species in the continually changeable environment can better bear environmental environment can better bear environmental pressure that that in the stable environment, pressure that that in the stable environment, there are species of unstable community have there are species of unstable community have better ability to adapt to environment.better ability to adapt to environment.
Moderate grazing that is mild disturbaceModerate grazing that is mild disturbace can facilitate the diversity and productivity can facilitate the diversity and productivity of community.of community.
It is useful for system It is useful for system evolutionevolution
The connotation of disturbance
The space arrange distribution characteristics of disturbace objectThe space arrange distribution characteristics of disturbace object
Of the same space and range or organization level, Of the same space and range or organization level,
the frequency time in unit time.the frequency time in unit time.
disturbance disturbance rangerange
frequency and frequency and
cyclecycle
disturbance disturbance intensityintensity
time scaletime scale
The energy values presented by disturbace factors when The energy values presented by disturbace factors when the disturbace happens. Its quantification analysis the disturbace happens. Its quantification analysis confirms the detailed unit according to the detailed confirms the detailed unit according to the detailed
type of disturbace, it is usually divided into: type of disturbace, it is usually divided into: mild, moderate and severe disturbace.mild, moderate and severe disturbace.
The detailed time and time span when disturbace happens, The detailed time and time span when disturbace happens, disturbace of different time will produce different disturbace of different time will produce different disturbace effect, for example, fishing catching, disturbace effect, for example, fishing catching,
forest felling, the artificial disturbace time is forest felling, the artificial disturbace time is
different, so the ecology effect will have big differencedifferent, so the ecology effect will have big difference..
Disturbance characteristics
multiplicity
relativity
dimension
incongruity
universality
It has influence of many aspects on ecosystem.
The same incident, it forms disturbance on ecosystem under some conditions other
conditions also have influence.
The difference in study scale, the definition of disturbance is also different. For the
disturbance incident on ecosystem, it may be normal disturbance in landscape scale.
The disturbance result may result in the capability enhancement of heterogeneity; it
can not coordinate with the original landscape.
It is existed in each scale and each space of nature world.
The main form of human disturbance
The felling and reclamation for forest and grassland vegetation.
Pollution(pesticide, life and industry rubbish and so on)
Collection (salvage collection on economic and medical valuable biology resources).
Hunting and catching. Introduction of alien species.
Water hyacinth also names as eichhornia crassipes, it is originally produced in South America, one of the harmful grass. It is extensively distributed in river, lake, asexual reproduction speed is very quick, forms the single superior community, blocks up the river channel and fills the lake.
Water hyacinth also names as eichhornia crassipes, it is originally produced in South America, one of the harmful grass. It is extensively distributed in river, lake, asexual reproduction speed is very quick, forms the single superior community, blocks up the river channel and fills the lake.
Because human activity intentionally or unintentionally introduces the foreign species into locals, they are quickly growing and generating, which harms the local production and life, change the local environment and bring great harm.
Biological invasion
Ecosystem has the self-adjustment and recovery ability, but it is very limited, once the interference exceeds the
adjustment ability, it will have irreversible damage.
resilience brecovery adisturbance degradation
Normal operation scope
resistance
ecosystem
structure and function
time
Figure 8-6 The conception structure reflects ecosystem structure and function on disturbance response
8.3.2 Disturbance and ecosystem adjustment
8.4.1 Connotation and characteristics of ecological restoration
Connotation ：
8.4 Restoration ecology theory
The main elements and process in changing the ecosystem degradation, adjust and optimize system
order, enables its structure function and ecology potentiality restores to the certain or original level
even up to the higher level.
涵盖范围 : Protecting the partial regions that are severely interfered.
Increasing the land productivity of the degenerated land. Enhancing natural protection value of landscape field
Recovering landscape scale and ecological process of partial regions.
Type of ecosystems
Total area/106hm2
Degraded area /106hm2
Proportion /%
farmland 140 28 20
grassland 400 132 33
forest land 165.2 31.2 25
desert 0.130 ―― ――
freshwater surface
0.743 0.245 32
scrapped mine site
2 ―― ――
Figure 8-1 Type and area of degraded ecosystems in China
Element principle dominated ecological elements.Restrictive and endurance law.Principle of energy flotation and material circulation. Community density restriction and species effect principle Complementation principle of ecological niche and specie Interference principle of boundary effect and ecology succession principleBiology diversity principleFood chain and food net principlePatch-passage—substrate landscape style principleSpace heterogeneity principle.Space scale and level theory
Element principle dominated ecological elements.Restrictive and endurance law.Principle of energy flotation and material circulation. Community density restriction and species effect principle Complementation principle of ecological niche and specie Interference principle of boundary effect and ecology succession principleBiology diversity principleFood chain and food net principlePatch-passage—substrate landscape style principleSpace heterogeneity principle.Space scale and level theory
Unity principle Cooperative restoration principle Scattering structure principle Openness principle Controllability
principle
Unity principle Cooperative restoration principle Scattering structure principle Openness principle Controllability
principle Economy feasibility and sustainability principle Technology operability principleSocial acceptability principle Harmfulness principle, minimum risk principle.Combination principle with biology, ecology and engineering technology. Benefit principleSustainable development principle.
Economy feasibility and sustainability principle Technology operability principleSocial acceptability principle Harmfulness principle, minimum risk principle.Combination principle with biology, ecology and engineering technology. Benefit principleSustainable development principle.
Principle of regional, difference and zonality
Principle of regional, difference and zonality
The principle
of ecology The principle
of ecology
The principle of geography The principle of geography
The principle of
statistics
The principle of
statistics
natu
ral law
n
atural
law
Th
e prin
ciple of social
econom
ic and
tech
nology
Th
e prin
ciple of social
econom
ic and
tech
nology
Th
e prin
ciple of ecological
restoration an
d
reconstru
ction
Th
e prin
ciple of ecological
restoration an
d
reconstru
ction
Figure 8-7 Basic discipline, theory and principle of ecological recovery and rebuilding （ revised by Sheng Lianxi， 2002 ）
The principle of ecological restoration
Figure 8-8 Soil and water conservation and ecological restoration of
Loess Plateau
B
C D
Characteristics: lower consumption, much profit and
sustainable
Concerned theory: system theory, engineering theory and
ecology theory.
Model: conception, letter, physics and math model.
Application: effluent and sewage resources disposal, forestry
protection, lake eutrophia, aquaculture, land improvement,
wasted land development and resource regeneration and so on
8.4.2 Ecological engineering
type of engineering
Traditional engineering
environmental engineering
ecological engineering
ecological engineering
basic unit Natural and
social systemNatural and social
system
Ecological system
and landscape cell
basic theory engineering science
Environmental science
Environmental engineering
Ecology, environment science
and engineering
genetics
Cell biology basic
energy fossil energy fossil energy
Renewable energy,such as solar
energy fossil energy
basic charge a large number a large numberReasonable
a large number
design features
act of man act of man
organization which assisted by human
act of man
control structure
arbitrariness pollution source Organism and
environment genetical
disturbace the
relationship
with nature damage recooling Coordination, no
pollution disturbance
biodiversity reduction change maintain or increase change
Notes： quoted from Qin Pei, An Shuqing, Yan Jingsong. Ecological engineering. Nanjing: nanjing university press, 2002
Figure 8-2 Comparison of ecological engineering and environmental engineering, biology engineering and traditional engineering
Ecosystem service: the environment conditions and utility human depend on to survive
8.5.1 Value evaluation of ecosystem
entertainment
environmental benefit
production function
basic function
four levels
direct value direct value
intrinsic value intrinsic value
indirect value indirect value
option value option value
ecosystem value ecosystem value
four types
Value evaluation of ecosystem
In 1997, ecologists such as Costanza carried out evaluation
on ecosystem type in the world, concluded that service total
value of global ecology was 33200billion dollar/year.
First periodical Chinese Science Bulletin in 2000, thesis
publicized by Zhang Xinshi academician in Value of
Ecological System in China. He carries out imputation for
the service function of China ecosystem, the total value of
China ecosystem value is 7783.448 billion Yuan(RMB)/year,
accounting for 2.71% of the world.
total economic value
total economic value
use value use value non-use value non-use value
direct use value
direct use value
indirect use value
indirect use value
option value heredity value existence value option value heredity value existence value
Direct
consumer goods
Direct
consumer goods Functional benefits
Functional benefits
Direct and indirect use
value in furture
Direct and indirect use
value in furture
maintain the use value and non-
use value
maintain the use value and non-
use value
knowledge the continued existence value such as moral
faith
knowledge the continued existence value such as moral
faith
food biomass
entertainment
health
food biomass
entertainment
health
Ecological function
Flood control Storm
protection
Ecological function
Flood control Storm
protection
Biodiversity Protecting biological
environment
Biodiversity Protecting biological
environment
irreversible living
environment
irreversible living
environment
living environmentendangeredspecies
living environmentendangeredspecies
Reduce the tangibility of personal value Reduce the tangibility of personal value
OCEDeconomic value categorizing systems of biodiversity
Figure 8-9 OCED economic value categorizing systems of biodiversity （ quoted from Sheng Lianxi， 2002 ）
Ecosystem management: under the perquisite that fully understand the integrity and complexity of ecosystem, aims at the expected material and product, ecological and social benefit, the management activity according to long time of monitoring result of the key ecological process and important ecological elements(Liao Liping, Zhao Shidong, 1999).
Basic principle: integrity, dynamic, regeneration, balance and diversity9environmental ecology, Sheng Lianxi etc, 2002, pp268-274).
Difficulty in management: the unexpected incident of ecosystem and different response for disturbance lacking of the ecology model establishment knowledge and principle, data, quality, sampling deviation and fault analysis.
8.5.2 Management theory of ecosystem
8.5.4 Ecology fragmentation Ecology fragmentation
Form (landscape structure) fragmentation.
The reduction in habitat, the complicated plaque shape, increases in boundary effect, reduction in core area square.
Fragmentation in ecology function
Ecology environment quality within habitat is decreasing, the element space of natural environment is not matching, the adaptability of environment reduces, there is no obvious change in outer shape, it is easily ignored, now it has attracted the highly attention of ecologist
It means due to human factors or environmental
change and resulted in larger square natural habitat
of landscape is gradually cut and broken or the
ecological function is decreasing. Including:
Figu
re of ecology fragmen
tation
[email protected] School of Environment, Beijing Normal University
8.6.1 Environment management in natural protection area
（ 1 ） Choice and square of protection areas
Place choice: the protection area must have enough complicated
habitat type; protect key species, especially for the key existence of
mutual benefit and mutualism species.
Square confirmation: according to the balance hypothesis of
ecosystem, the larger square, and the more beneficial for biology
diversity. The key point is that ecology characteristics of protected
target species. The square of surround ecosystem and that similar to
protection area can be much less.
8.6 Case study
The Tibetan antelopes are migrating in conservation hinterland
Kekexili nature conservation
（ 3 ） Function division of conservation hinterland
Cuo Na Lake
Cuona Lake is the core area of black-necked crane protection area in Lincuo of Xizang, the Qingzang railway under construction is only more than 10 meters away form it in order to prevent from being polluted, and people implement strict engineering supervision and control measure.
（ 4 ） The connection and corridor between
conservation， landscape protection
Tibetan herdsmen are ongoing vegetation restoration and reconstruction
Wild animal Channel mimetic diagram of Qinghai-Tibet Railway The upward passage of tunnel: it is designed for highland animals in high mountain, it sets fence prevents animals entering tunnel, and combines with bridge forming bridge-tunnel compound passage, there are totally 3.
The upward passage of tunnel: it is designed for highland animals in high mountain, it sets fence prevents animals entering tunnel, and combines with bridge forming bridge-tunnel compound passage, there are totally 3.
The downward tunnel of bridge: it is designed for medium and small animals such as Tibetan antelope, goal and so on, the net height if passage below tunnel is required larger than 3 meters, there are totally 13.
The downward tunnel of bridge: it is designed for medium and small animals such as Tibetan antelope, goal and so on, the net height if passage below tunnel is required larger than 3 meters, there are totally 13.
Passage of level gentle slope: the road base angle on both sides of railway is not exceeding 35 degree, the height is less than 2.5 meters, and it sets
warning signboard, there are totally 7
Passage of level gentle slope: the road base angle on both sides of railway is not exceeding 35 degree, the height is less than 2.5 meters, and it sets
warning signboard, there are totally 7
Thank youInvite questions
Thank youInvite questions