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15Management of Integrated Ecological-economic Processes in the Land-Sea System Maintaining the Marine Environment Quality
I.E. Timchenko, I.K. Ivashchenko, E.M. Igumnova
Marine Hydrophysical Institute, Russian Academy of Sciences, Sevastopol,
Russian Federation
Adaptive model for maintaining the processes in the ecological-economic system connected the "Land-Sea" system industrial output, on the one hand, and the contamination level and the marine environment biodiversity index, on the other, is proposed. The paper contains the development of modeling results of such systems obtained using the adaptive method of causes method (the results were published in the 3rd number of this journal, 2015). More complex model of the "Land" economic subsystem which had a great number of logical agents of production profitability management is applied. In the "Sea" ecologic subsystem a model for monitoring over biochemical processes forming the marine environment biodiversity index is proposed. These processes are: the concentrations of phytoplankton, zooplankton, bioresource, biogenic elements, oxygen, carbon dioxide and detritus. Biodiversity index, along with contamination level, was applied for ecological control of marine environment quality. External impact on the "Sea" subsystem is represented by solar radiation, sea upper layer temperature and wind velocity modulus. Being based on analysis of the effect of economic sanctions for pollution upon the processes in marine ecosystem, the model is intended to find a rational balance between the income from marine resources use and the expenditures for preserving marine environment quality. Management agents controlling balance between consumption and reproduction of marine resources are applied in the models of "Land" and "Sea" subsystems, as well as in the integrated system model. The results of great number of simulation experiments demonstrating the possibility of complex "Land-Sea" system management in the modes of rational natural resource use are given. Scenarios of ecological-economic processes arising at transferring industrial production on ecologically clean technologies are constructed, and advantages of such a variant of nature management are shown.
Keywords: ecological-economic model, adaptive balance of causes, scenarios of processes.
DOI: 10.22449/1573-160X-2015-5-67-85
© 2015, I.E. Timchenko, I.K. Ivashchenko, E.M. Igumnova © 2015, Physical Oceanography
Introduction. Significance of the coastal zone ecological economics increases with the development of marine resources consumption technologies [1 - 4]. As far as the anthropogenic load on the coastal marine environment is constantly increasing, its main quality, along with the biological productivity, becomes its assimilative capacity. In the work [5] the management problem of the coastal zone integral ecological-economic processes, which develops in the model of generalized Land -Sea system under conditions of the pollution level control, is considered. The model is constructed by the adaptive balance of causes method and contains management agents, which allow setting the scope of the economic sanctions imposed on the production, depending on the pollution level of the marine environment.
In this work the research had been developed by the usage of more complex models of subsystems within the Land - Sea unified system. Integral characteristics of the ecological state of the marine environment became the waste pollution level and biodiversity index. Each of these two indexes is formed under the impact of great number of different factors. But to simplify, it was considered that the level of pollution is determined by the balance of pollution accumulation rate and self-PHYSICAL OCEANOGRAPHY NO. 5 (2015) 67
clarification rate of the marine environment as a result of chemical and bacteriological reactions and mixing of water masses, and the index of biodiversity decreases in proportion to the pollution level. The task is to research the environmental management balance in conditions when the economical benefits of production release depends on the costs required for the protection of the marine environment from pollution and the conservation of biodiversity index. Besides, it is necessary to evaluate the economic viability of the Land economical subsystem to transfer it to the eco-friendly production technologies.
The structure of the management model for industrial profitability and marine environment ecological state support in the Land - Sea system. The model consists of subsystem Sea, which represents the marine ecosystem processes (they form an index of biodiversity of the marine environment), and the subsystem Land, which describes the economical processes determining the production profitability and pollution level of the marine environment. Both subsystems are combined into a single system by the balance management unit of subsystems Sea and Land functioning by criteria of marine environment quality preservation.
Fig. 1. Conceptual model of ecological-economic production profitability balance management and ecological state of coastal marine environment
For the management unit the conceptual model, which controls ecological-economic production profitability balance and ecological state of coastal marine environment, is proposed. The scheme of this model is depicted in the fig. 1. Production volume V causes the pollution of marine environment PL, which reduces
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concentrations of phytoplankton PP, zooplankton ZP and bioresources BR, affecting the biodiversity index BD. Environmental management is based on the monitoring of pollution index PL and biodiversity index BD, for what the exposure limit values of PL* and BD* were used. The pollution level monitoring is performed by management agent AGPL, and biodiversity index monitoring - by AGBD agent. In the production and environment protection management units these agents affect the production cost through the pollution tax, which is proportional to PL level, and through the penalties for exceeding maximum permissible level of PL*. Besides, it is imposed a penalty for reducing the biodiversity index BD below the minimum permissible level BD . Due to the penalties, the fund of environmental protection actions EP is formed, and these actions decrease the pollution level and raise biodiversity index of the marine environment. Thus, the chain of stabilizing feedback, which keeps up the ecological-economic environmental balance at the required level, closes.
Conceptual model of ecological subsystem The Sea. The model of ecological subsystem The Sea links biodiversity index with marine environment pollution level, which happens, mostly, because of domestic and industrial waste inflow from the coastal area. The pollution inflicts a great harm to bioresouces of the sea. In the developed ecosystem model the higher food chain link (phytoplankton -zooplankton - fish (bioresourse)) is related to bioresources. The state of food chain is characterized by concentration values of phytoplankton PP, zooplankton ZP and bioresources BR. Processes, which describe the time changes of these concentrations, are included to the Sea subsystem model along with other resources of food chain development: concentration of oxygen OX, carbon dioxide CD and biogenic elements BG. To close the chain of biochemical reactions in marine environment, the process of detritus DT formation and its transformation into the biogenic substances, was included to the given model. On the basis of these conclusions the cause-effect relationship system of ecological subsystem The Sea (given in the fig. 2) was developed.
The resource limitation agents of substance concentration increase are the important elements of the model. The limitation specifies which type of resources, necessary for the concentration increase, at the moment is available in minimal amount. For example, for the phytoplankton concentration increase it is necessary to have the rise of carbon dioxide CD and biogenic substances BG concentration, and also to have the increase of solar energy SR. The increase of phytoplankton concentration depends on that type of recourses, which concentration is minimal in comparison with the other resources, and it happens because of the constant change of recourse amounts.
That's why four management agents, shown in Fig. 2, are included to the model. AGPP agent limits the phytoplankton concentration increase by solar energy SR, carbon dioxide CD and biogenic substances BG; AGZP agent limits the zooplankton concentration increase by phytoplankton PP, oxygen OX and biogenic substances BG; AGBR agent limits the bioresource concentration increase by zooplankton ZP, oxygen OX and biogenic substances BG; AGbg agent limits the biogenic substance concentration increase by detritus DT and oxygen OX.
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In marine ecosystem the processes are in the state of constant dynamical balance with external impacts. The main factors of external impacts are solar and atmospheric impact, water mass dynamics and pollutant inflow. To simplify the model we didn't consider the impact of advection and water mass diffusion at the concentration of the modeling substances. This impact on pollution concentration PL (along with chemical-bacteriological reactions) is indirectly considered in function, by which the process of marine environment self-clarification had been modeled.
Fig. 2. Conceptual model of ecological subsystem the Sea
70 PHYSICAL OCEANOGRAPHY NO. 5 (2015)
The external impact on ecosystem is represented by the intensity of solar radiation SR, the temperature of the sea upper layer TW and the wind velocity module WF. It was assumed that the annual temperature variation (average on the volume of the modeled marine environment) affects the concentration of phytoplankton, as well as the concentration of oxygen and carbon dioxide, which decreases with the raise of temperature. It was also accepted that with an increase of wind mixing in the upper layer of the sea the concentration of oxygen also increases.
Conceptual model of economical subsystem the Land. The purpose of the Land subsystem model constructing is a forecast for scenarios of economic production processes, which affect the pollution levels of the marine environment and biodiversity. Proceeding from such statement of the modeling problem, the most important subsystem processes were selected and a scheme of cause-effect relationships between them is constructed (fig. 3).
Fig. 3. Conceptual model of ec onomical subsystem the Land
In the block of production profitability the consolidated incomes for the appointed period of time are compared with working expenses for the same period of time. Depending on the profitability level the p ossibility of demand satisfaction on the Land subsystem production is estimated and production quota, provided by the existing productive resources, is determined. In the management unit of ecological-economic balance of production profitability and marine environment quality, economical efficiency of production subordinates the marine environment ecological PHYSICAL OCEANOGRAPHY NO. 5 (2015) 71
state. Here the penalties for the pollution of the sea by industrial waste are established and governmental nature protection fund is formed.
Specification of the Land subsystem conceptual model is performed by information technology of adaptive economical systems ABC AGENT model construction, which is described in several works [3 - 6].
The equations of adaptive economical subsystem the Land. The main operations of economical system are presented as balance conditions, where the modeling system variable adapts to the algebraic sum of sources (incomes) and outflow (expenses) of different substances (goods, services, resources). These equations are considered in several articles and monographs about the adaptive balance of causes method (ABC-method) [3, 6]. That's why we'll just enumerate the main equations for the variables of the Land subsystem model. The equations have a module structure and it will be illustrated by the example of equation (1) for the warehouse of manufactured products. Product demand is satisfied by the sale of manufactured products, accumulated in the warehouse, and by the additionally manufactured production. We denote the current amount of ready-for-sale production in the warehouse as H, and assume that it fluctuates around the average value CH . With continuous production supply and sell the balance equation for function H could be represented as a modular equation of ABC-method and the equation for the management agent that restricts the amount of the manufactured production by the warehouse capacity:
dH
— = 2r-H[Ch - (H - F + S)], (1)
dt
V - S = IF{V - S < 0;0; IF[V - S > 2CH ; 2CH ; V - S]} ,
where V - the intake of manufactured production to the warehouse, S - its sell, rH - the relation of specific rate of change H to the value H, and the value 2 CH is a warehouse resource capacity. Other equations of economical subsystem are represented in the same way:
- the equation of the resource dynamics — of economical subsystem:
dH
= 2rHuHh[C-u - (H - Vh + Su)], (i = 1, 2, ... , n); (2)
- the equation of production current capital H2:
dH
dt = 2r-2 H 2[C- 2 - (-2 -1 - -3 + S2 + S3)]; (3)
- The equation of production investment (loan) dynamics H3:
dH
dt
3 = 2r-3H3[C-3 -(H3 -V3 + S3)]. (4)
In the equation (3) current profit of economical subsystem the Land is denoted by I.
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PHYSICAL OCEANOGRAPHY NO. 5 (2015)
The equations of adaptive ecological subsystem the Sea. To construct the formal model of subsystem the Sea we'll use the designations of ecosystem variables and the scheme of cause-effect relationships shown in the fig. 2. Using the ABC-method model equations we obtain the following equation system of marine ecosystem adaptive model: dPP
-= 2rPPPP{CPP - [PP + aPP/2PZP - AGPP (BG, SR, CD) - aPP/TWTW - aPP/WPWF +
dt
+aPP / PLPL\},
dZP
— = 2rzPZP{CzP -[ZP + azP/brBR - AGZP(OX,PP,BG) + azP,PLPL\] , dt
dBR = 2rBRBR{CBR - [BR - AGBR (OX, ZP, BG) + aBR/plPL\} , dt
dOX
^ - lroxOX{Cox - [OX + aox/brBR + aox/zpZP - aox/ppPP + aox/bgBG + ^
+aox / TWTW — aox (WF )]}, dCD
" — 2rcDCD{CCD — [CD — acD/BRBR — aCD/ZPZP + aCD/PPPP + aCD/TWTW]} ' dt
dBG — 2rBGBG{CBG - [BG - AGbg(OX,DT) + aBG/ppPP + aBG/zpZP + aBG/brBR]} > dt
r — 2rDTDT{CDT — [ DT — aDT / BRBR — aDT / ZPZP — aDT / PPPP + aDT / BGBG + dt
+aDT / oxox ]}-
In the equation system (5) the coefficients rMN are the average values of the relations of variable MN rate change to the value of this variable, C'MN - average value of MN variable, aKL/MN - the coefficient of MN variable impact on the KL variable. For the resource limiting agents the following expressions are used:
AGpp ( BG, SR, CD) — IF[Mpp (t ) — app, BaBG{t ); app, mBG{t ); 0] +
+IF[Mpp (t) — app / srSR(0; app ! sRSR(t ); 0] + IF[Mpp (t) — app ! coCD(t); app ! coCD(t); 0],
where Mpp (t) — argmin[app,BGBG(t); app,sRSR(t); app,CDCD(t)] ;
AGzp (OX, PP, BG) — IF[Mzp (t) — aZp/oxox(t); aZp/oxox(t); 0] +
+IF[Mzp (t) — aZp / ppPP(t ); aZp, ppPP(t ); 0] + IF[Mzp (t) — aw, BGBG(t ); aw, BGBG(t); 0],
where Mzp(t) — argmin[azp/oxox(t);azp,ppPP(t);azp,BGBG(t)] ; (6)
AGbR (ox , PP, BG) — IF[Mbr (t) — aBR / oxox (t); aBR / oxox (t);0] +
+IF [Mzp (t ) — aBR / zpZP(t ); aBR, zpZP(t ); 0] + IF [Mbr (t ) — aBR, bgBG (t ); aBR, BGBG(t ); 0],
where Mbr (t ) — arg min[aBR / oxox (t ); aBR, zpZP(t ); aBR, bgBG (t )] ;
AGbg (OX, DT) — IF[Mbg (t) — abg/oxox(t); abg/oxox(t); 0] +
+IF[Mbg (t ) — aBG / dtDT (t ); aBG / dtDT (t );0],
where Mbg (t) — argmin[abg / oxox (t); aBG/dtDT (t )].
PHYSICAL OCEANOGRAPHY NO. 5 (2015) 73
The coefficients of impact ai}. in the model equations could be identified in several
ways, considered in the works [3 - 6].
The scenario construction in the economical subsystem the Land. The developed economical model shows the dynamics of all the Land subsystem processes, described by equations (1) - (4). In the series of numerical experiments the calculations for 370 time steps were performed. All the variables are presented in dimensionless form. The maximally possible production loan is H3 = 300, and
the loan percentage -a = 0.01H;. The scenarios of processes obtained under these conditions are shown in fig. 4.
140 -
120 n 100 80 60 40 20 4
I
120 -100 -80 -60 40 20 H 0
Ha
t
50
150
250
350
50
150
250
350
350 -, 300 250 200 -150 100 50 H 0
H3
11 111 50
H *
I'M"
150
250
111 1 350
5.0 -, 4.5 4.0 3.5 3.0 2.5 H ■2.0
EF
50
I ' I 11
150
250
350
d
140 -120 -100 -80 -60 -40 -20 -0 -
H-n
50
150
250
350 -1
f
Fig. 4. Scenarios forecasted by economical subsystem the Land
b
a
t
c
e
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PHYSICAL OCEANOGRAPHY NO. 5 (2015)
To asses the impact of ecological subsystem the Sea on the production profitability, during the construction of scenarios, depicted in the fig. 4, a - d, the impact of environmental taxes and environmental pollution penalties were not considered at first. Horizontal lines in the fig. 4, a, depict the constant scenarios of demand D for the subsystem production, the price P and the cost price E of this production. Frequent vertical lines show the values of daily production sale S, which depends on the production support by all kinds of resources. The amount of daily purchased production resources Vu, V12, V13 are given in the fig. 4, b. These amounts depend on the ratio of current assets H2 and current investment (loans) values H3, which could be used for the purchase of the missing resources to meet the demand. As it follows from the fig. 4, c, production have to constantly invest in the resources
purchase a maximum permissible value of accumulated credit H**.
To monitor the production profitability EF, the ratio logarithm of income 7acc, accumulated over some period of time t, to the accumulated expenses Eacc was used:
EF = ln , /acc = j>S(t)dt, Eacc = ¡EV(t)dt. (7)
e + Eacc 0 0
The scenarios of these processes are given in the fig. 4, d, e. Excluding the environmental penalties for marine pollution, the profitability remained constant.
In a second series of experiments the conditions, under which the economical subsystem should make contributions towards environmental objectives from the current assets in the amount of 0H2, are simulated. The production profitability scenarios are constructed for different percentage of contributions 6. The obtained results are shown in the Fig. 4, f. The figure shows the decrease of production profitability with the increasing of environmental sanctions. With significant contributions (6 = 0.5) production becomes unprofitable at 280th step of calculations.
Construction of process scenarios for ecological subsystem the Sea. To
evaluate the stability and controllability of ABC-model (5), (6) the numerical experiments were performed. Model equations were represented in the finite differences and were resolved at (0.370) time interval of iteration steps. The ecosystem variables are written in dimensionless form, and are reduced to the overall variability scale (0.10) by means of linear transformation. The values of several model coefficients are given in the table.
The coefficients of intersystem influences in the ecosystem model
aKL / MN PP ZP BR OX CD BG DT
PP 1 - 0.6 - - 1.5 0.6 -
ZP 0.6 1 - 0.4 0.6 - 0.8 -
BR - 0.4 1 0.3 - 0.6 -
OX 0.5 - 0.6 - 0.3 1 - - 0.3 -
CD - 0.5 0.3 0.2 - 1 - -
BG - 0.4 - 0.3 - 0.3 0.7 - 1 0.3
DT 0.4 0.4 0.2 - 0.7 - - 0.3 1
In the series of experiments features of the Sea subsystem model firstly were verified in isolation from the Land subsystem. That's why the effect of pollution
PHYSICAL OCEANOGRAPHY NO. 5 (2015) 75
inflowing the sea from the shore, was eliminated by equating to zero the coefficients app/PL, azp/PL, aBR/PL in the corresponding equations (5).
To assess the effect of climatic and weather conditions on process scenarios, represented by the ecosystem model, the external effects were simulated: solar radiation intensity SR, temperature of the sea upper layer TW and wind velocity modulus WF. The graphs of simulated atmospheric effects and sea temperature are given in Fig. 5, a.
a
• 11 ' i ' i 50
-n
150
i '11111 '1111 250
350
c
Fig. 5. The external effects (a) and the reaction to them of marine ecosystem variables (b, c) (wind velocity graph WF is shifted down at 1)
In the first experiment the resource constraints are removed for the further evaluation of their role in formation of ecosystem process scenarios. Therefore, the logical management agents (6) in the equations (5) are replaced by the influence sums:
ApP (BG, SR, CD) = aPP/ BGBG(t ) + aPP/ SRSR(t ) + aPP / CDCD(t ), A*ZP (OX, PP, BG) = aZP / oxOX (t ) + aZP, PPPP(t ) + aZP, bgBG (t ), (8) ABR (OX, PP, BG) = aBR/ox OX(t) + aBRlZPZP() + aBRlBGBG(t), ABg (OX, DT ) = a
BG / OX
OX (t ) + aBG / dtDT (t ).
b
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PHYSICAL OCEANOGRAPHY NO. 5 (2015)
In these conditions by the predetermined intensity of the external effects, the most defined model reaction manifested in those process scenarios, which were directly depended on the near-water wind modulus, annual change of illumination and sea temperature. Significant fluctuations of the oxygen concentration in the upper layer (OX curve in the Fig. 5, c) and the smoothed annual change of carbon dioxide and detritus concentration (CD and DT in the Fig. 5, c) were represented. Phytoplankton concentration curve (PP in the Fig, b) is formed mainly due to the annual change of solar radiation (SR in the Fig. 5, a). Values of zooplankton and bioresource concentrations (ZP and BR in the Fig. 5 b) were affected by minor changes due to the oxygen concentration fluctuations.
In the next experiment the management agents (6) were turned on. The obtained results are shown in the Fig. 6. The resource limiting agents engaging significantly changed the scenarios of ecosystem organisms supplying with the vital resources. As it follows from the figure, management agent scenarios are oriented at minimum values of their arguments. For example, graph values of the phytoplankton limiting by biogenic substances, solar radiation and carbon dioxide ( AGPP curve in the Fig. 6, a) due to the agent AGPP (BG, SR, CD) correspond to the minimal values of SR and CD curves. The curve BG lays above them, and it means that biogenic substances didn't affect on the phytoplankton concentration.
9
8 H
7 6
5 H 4 3 2
1 H 0
50
150
250
350
50
150
250
350
9
8 -
7 -
6
5
4
3
2 H 1 0
50
150
250
350
50
150
250
350
d
Fig. 6. Functions of resource limiting agents in the model of the Sea subsystem and the substance concentrations formed by them: a - phytoplankton, b - zooplankton, c - bioresource, d - biogenic elements
The results of these experiments concluded that management agents are really important in the given model of marine subsystem. The model has a relatively high
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b
a
c
sensitivity to external effects and adequately reproduces a cause-effect relationship between the modeled processes. Therefore, its intersystem influence coefficients (table) were saved when including the subsystem the Sea to the general simulation model of ecological-economic processes with economical subsystem the Land.
The marine bioresource consumption balance management on the basis of the integrated Land - Sea system' model. Consolidation of subsystem the Land and the Sea models into the integrated system was carried out by management unit of ecological-economic production profitability balance and levels of pollution contamination and marine environment biodiversity. The developed balance management scheme is based on the negative feedback between two subsystems, which operated in the following way. The increase of marine environment pollution concentration PL was taken as proportional to the accumulated amounts of selling production Sacc. Natural purification of the marine environment occurred due to the
turbulent mixing and chemical-bacteriological reactions favored the decrease of concentration. The first of these two factors was considered to be proportional to the pollution level PL with a certain coefficient e, and the second factor - to the amount of money accumulated in the environmental protection action fund EP. That's why ABC-method modular equation for the pollution concentration has the following form:
dp]
— = 2rpLPL[CZp - (PL + apL / EpEP + sPL - apL, sSacc )]. (9)
dt
The environmental activities fund EP of was formed by the accumulation of contributions TX from the economic subsystem profit. To improve the ecological state of the marine environment the environmental tax, proportional to the concentration PL value, to which was added an environmental penalty, when the concentration of contaminants got above the maximum permissible value PL, was used. The inclusion of environmental penalties and their amount was controlled by the management agent AGTX (PL, PLL ). Therefore, the following equations for EP and TX values were used:
dt
dTX
dEP
= 2VepEP[CEP - (EP -aEP/TxTXacc + F^P)], (10)
= 2rTXTX [CTX - [TX - aTX / PlPL - AGTX (PL, PL*)]}, (11) dt
where FEP - additional investments to the EP fund; AGTX (PL, PL*) = IF {PL < PL*; 0; aTX [1 - exp(bTXr)]} .
To close the feedback loop between the subsystems the Land and the Sea, biodiversity index of the marine environment BD is determined by the concentrations of the aquatic organism main groups - phytoplankton PP, zooplankton ZP and bioresource BR, which sufficiently depend on the marine environment pollution level:
T~ = 2rBDBD[CBD - (BD - aBD/PPPP - aBD/ZPZP - aBD/BR BR)]. (12) dt
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PHYSICAL OCEANOGRAPHY NO. 5 (2015)
Management of the unified Land -Sea system was carried out through the dependence of production costs on the pollution sanction level TX and the marine environment biodiversity index BD:
dF 3
— = 2rEF{CE - [F - £ P,q, - aF,TXTX - AGbd (BD, BD*)]}, (13) dt
where p -coefficients of resources price impact q; AGbd(BD,BD*) = IF{BD > BD* ;0; aBD[1 - exp(bBDr)]} .
The increase of pollution penalties and decrease of the biodiversity index below the value BD* increased production costs and decreased the production profitability.
It should be noticed that the unified Land -Sea model (1 - 13) describes the ecological-economic development processes in detail. In this model the environmental management of the marine environment is performed not only by the pollution level criterion, but also by the biodiversity index. Using the unified model a series of numerical experiments was carried out. The results of one experiment are summarized in Fig. 7.
At the beginning of the experiment almost continuous production sell S under the constant demand D and the market value P (Fig. 7, a) was observed. At the same time increased the pollution concentration in the sea (Fig. 7, f). Biodiversity index have been fluctuated around the maximum permissible value BD* = 8 (Fig. 7, g). So, the major impact on the production cost was provided by the pollution level. Production cost increased rapidly and at the 130th time step it became equal to the product price and it was the cause of the first stop of the production (Fig. 7, a). The subsystem Land, which got necessary types of resources using the maximal loan amounts (Fig. 7, c) also stopped that purchases (Fig. 7, b).
The suspension of production had been lasted until the 239th step. After the suspension of production the pollution level reduced due to the processes of marine environment self-purification and also because of environmental action fund. The velocity of marine environment pollution concentration decrease determined in this experiment has provided its fall to the value PLL = 3.7 at the 239th step of experiment, when the sanction agent AGTX (PL, PL*) in the equation (11) abruptly reduced the production cost and production management agents resumed the production (Fig 7, a). During the suspension of production period the growth of accumulated incomes stopped (Fig. 7, d) and took place a partial repayment of accumulated loans (Fig 7, c) from the available current assets. Thus, the current assets reduced (Fig. 7, e) and the accumulated expenses kept growing (Fig. 7, d). By this fact could
be explained the decrease of total production profitability (Fig. 7, h).
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8Q
PHYSICAL OCEANOGRAPHY NO. S (2Q1S)
Since the resumption of production at the 239th step the above-mentioned pollution level management cycle repeated again. Thus, during the entire experiment the pollution level didn't exceed the upper limit of permissible values PL < 4.0 and tended to decrease (Fig. 7, f). The total profitability remained positive and had a tendency to stabilization.
The scenarios given in Fig. 7, were obtained during the experiment, when it was set the problem to find such a marine pollution sanction value at which the permissible pollution level could reach the value PLL = = 3.6, but should not exceed the value PL = 4.0. During the calculations it was determined that to provide these conditions the contribution from the current assets of the Land subsystem to the environmental actions fund should make about one percent (в = 0.01).
Thus, the ecological scenarios PL, BD and also economical scenario of profitability EF, forecasted by the unified the Land -Sea model, allowed us to find the necessary environmental balance. The numerical experiments showed that there are different variants of the Land -Sea model usage to find this balance.
Production volumes of the Land subsystem and, consequently, the pollution level affected the biodiversity index by the concentration values of phytoplankton, zooplankton and bioresource in accordance with the equation (12). The permissible value of biodiversity index lower bound BD* = 7.8 was found and it was set the problem to determine the necessary amount of pollution sanctions at which the BD index stay above this bound. The numerical experiment was performed with the same Land - Sea model parameter values as in the above-mentioned case. Scenarios of ecological-economic processes obtained during this experiment are shown in the Fig. 8.
Due to the use of AGBD (BD, BD*) management agent in the equation for production cost (13), the production cost curve E (Fig. 8, a) became more variable than in the first experiment (Fig. 7, a). Now it was affected by two management agents: AGTX(PL,PL*) - through the equation (11) and AGBD(BD,BD*)-through the equation (13). As a result, the sanction amounts affecting the production cost increased, and the production cost scenario stopped the production for 5 times, whereby the pollution level PL (Fig. 8, f) and biodiversity index BD (Fig. 8, g) were kept near the maximum permissible values. With the parameters of the Land - Sea system model management, which were used in these calculations, total production profitability decreased (Fig. 8, h). Negative tendencies were observed in the scenarios of ecological processes - the phytoplankton, zooplankton and bioresource concentrations decreased.
To improve the ecological state of the marine environment the size of the sanctions imposed on the economic subsystem should be increased at the cost of further reducing of the total production profitability. As an alternative variant it was considered the changing of production itself - transferring to the eco-friendly technologies. But the transferring to such technologies requires a significant investment.
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The production should allocate certain funds to the special fund of new environmental technologies EP, which eliminate or significantly reduce the pollution level.
PL* PL
250
g
1 111 111 i1111 i11111 '11 111 '1111 50 150
350
12 1 10 -8 -6 -4 -2 -0 i
50
f
150 250 h
350
Fig. 8. The scenario management results of ecological-economic processes by the pollution level criterion PL and the marine environment biodiversity index BD
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e
0
To test the effectiveness of the production transferring to eco-friendly technologies, the following experiment was performed. In the model of ecological-economic system Land - Sea the fund of environmental activities EP was simulated, which accumulated funds from the marine environment pollution penalties. In addition, a certain part of current assets was regularly allotted to this fund (e.g. 0.001H2). For the comparability of the modeling results the model parameters remained the same with the exception of the fact that now in the equation for pollution level (9) the impact of EP fund was considered and the equation for EP took the following form:
dEP
— = 2VepEP[CEP - [EP - (aEP/txTX + aEP,HiH2 )acc ]}. (14)
dt
The scenarios of ecological-economic processes in the Land - Sea model, obtained by the simulation of production transferring to the eco-friendly technologies, are given in the Fig. 9. As it follows from the Fig. 9, f in the initial period of the experiment (up to 90th time step) an increase of pollution concentration occurred and the production cost increased (Fig. 9, a) due to economic sanctions (Fig. 9, e). At that period we haven't enough funds for introduction of new technologies (Fig. 9, c). So, after the 90th step occurred a momentary stop of production (Fig. 9, a). But since that period of time the funds accumulated in the fund of environmental activities began to exceed the total amount of economic sanctions, as the summand aEP / HjH2in the equation (14) tended to sustainable growth and the summand
aEPTTXTX rapidly decreased, following the pollution level curve (Fig. 9, f). As a
result, the amount of accumulated means of environmental activity fund rapidly increased.
According to the idea of simulation experiment the increase of the fund means allowed us to transfer the production to the eco-friendly technologies. The graph of total production profitability is indicative (Fig. 9, h). In the initial period of time before the transfer to the new technologies the same profitability drop as in the experiment without transferring to the new technologies was observed (Fig. 8, h). But after the 9Oth step of time calculations the total profitability graph at first stopped the decrease and then a tendency of growth was acquired.
The effectiveness of production transfer to the eco-friendly technologies became obvious when we compare the graphs of accumulated incomes and accumulated expenses of the experiment without a transfer to eco-friendly technologies (Fig. 8, h) with the same graphs in another experiment (Fig. 9, d). By the end of the
experiment the accumulated expenses were almost equal: Eacc = 405 -103 c.u. -without transferring to the new technologies and Eacc = 414 -103 c.u. - with the transferring. But the accumulated incomes in the experiment with the transition to the new technologies appeared to be essentially higher. Their amount was 7acc = = 1.25-106 c.u., whereas without transition to the new technologies they amounted Iacc =0.41-106 c.u.
Thus, the simulation experiment allowed us to quantify the economic benefits of the production transferring to the eco-friendly technologies. The decrease of ma-
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rine environment pollution level by the end of experiment almost to zero positively impacted on the marine environment ecological state.
Fig. 9. Scenarios of ecological-economic processes in the Land - the Sea system during the production transfer to the eco-friendly technologies
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The concentrations of phytoplankton and zooplankton increased and emerged a tendency of bioresource concentration growth, which in the end of the experiment was weakened by the seasonal factors (Fig. 10, a). In this regard the concentration of biogenic substances decreased and the detritus concentration increased (Fig. 10, b). The consequence of the new technologies transferring was an abrupt decrease of pollution level (Fig. 9, f) and a significant increase of biodiversity index (Fig. 9, g), which reached its maximum value conditioned upon the given marine environment resource capacity by this parameter 2CBD = 10.
7 -6 -5 -4 -3 -2
I......................................................
T
50
150
250
350
T"
50
150
250
350
b
Fig. 10. Scenarios of ecological processes during the production transferring on the eco-friendly technologies
Conclusion. The simulation experiments performed applying the Land - Sea model confirmed the applicability of ecological-economic system adaptive models for the finding of marine resources consumption and reproduction rational management. The production transferring on the resource-saving technologies is more profitable, because the investments for eco-friendly technologies introduction lead to the reduction of penalties and production suspensions for the ecological reasons, and consequently increase the production efficiency.
Acknowledgements. The research was performed with the financial support of Russian Foundation for Basic Research within the framework of project No. 1445-01013/14.
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a
REFERENCES
1. Daly, H., Farley, J., 2010, "Ecological Economics: Principles and Applications. 2nd edition", Washington, Island Press, 544 p.
2. Voinov, A., 2008, "Systems Science and Modeling for Ecological Economics", Academic Press, 430 p.
3. Timchenko, I.E., Igumnova, E.M., 2011, "Upravlenie ekologo-ekonomicheskimi protsessami v integral'noy modeli pribrezhnoy zony morey [Management of the coastal integral model ecological and economic processes]", Morskoy gidrofizicheskiy zhurnal, no. 1, pp. 48-66 (in Russian).
4. Ivanov, V.A., Igumnova, E.M. & Timchenko, I.E., 2012, "Coastal Zone Resources Management", Kyiv, Akademperiodika, 304 p.
5. Timchenko, I.E., Ivashchenko, I.K. & Igumnova, E.M., 2015, "Upravlenie integral'nymi eko-logo-ekonomicheskimi protsessami v sisteme "Bereg - more " [Management of the integral ecological and economic processes in the system "Land - Sea"]", Morskoy gidrofizicheskiy zhurnal, no. 3, pp. 62-77 (in Russian).
6. Timchenko, I.E., Igumnova, E.M. & Timchenko, I.I. 2000, "Sistemnyy menedzhment i ABC-tekhnologii ustoychivogo razvitiya [System Management and ABC-technologies of sustainable development]", Sevastopol: MGI NAN Ukrainy, 225 p. (in Russian).
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