Erekle Kechxoshvili

The monograph is an analysis of the results of the transition of Georgian agriculture to market relations. It explains in detail economic concepts and terms; ways of further development of agriculture are outlined; foreign experience in agricultural intensification was considered and recommendations on the organization of agricultural production were given. The methods for determining the economic efficiency of agriculture as a whole and its individual industries, the agricultural development of the region and the rules for assessing the cost of land are given.                                                                                             

Particular attention is drawn to the chapters of the monograph, which disassemble the methods for determining the cost of irrigation water.                                                           

The need for a transition to paid water use is justified. The idea of ​ ​ creating associations for irrigation and mechanization maintenance is justified. The prices for irrigation and mechanization works are given.

The monograph addresses the issues of the economic cost of water resources, their formation and circulation in nature and the production sector; describes in detail the existing problems of nature conservation, issues of water management and related resources. The main part of the book is devoted to the study of the criteria for evaluating investment projects; consideration of the existing requirements for making management decisions and evaluating investment projects taking into account changes in the value of money over time; current methods for assessing the effectiveness of investment projects are described; examples of calculating the economic effectiveness of investments in the rehabilitation of irrigation systems in Georgia are given

Methodological recommendations are devoted to the design and operation of drainage systems on waterlogged lands of Georgia. They represent an attempt to generalize the almost century-old history of the development of the Colchis lowland. The reasons for overwetting of lands, natural conditions of the Colchis lowland, elements of drainage systems and their purpose, calculation and design methods are considered. Exploitation issues are illuminated taking into account modern conditions, farm small-contour land ownership.

The textbook deals with practical issues of irrigation systems calculation. Brief theoretical data on these issues and examples of calculations are given. 

The textbook is intended for undergraduate students in agroengineering and will be useful for readers interested in these issues.

The environmental project in Erekle II Street in the city of Sighnaghi envisages developing the storm-water and anti-landslide measures. For this purpose, the landslide section in Erekle II Street city of Sighnaghi was subject to the topographic survey. With the purpose of the engineering-geological evaluation of the object, 3 boreholes with the total length of 20 m were made. Ground and water samples were taken from the boreholes and were subject to the laboratory analysis. In addition, the hydrogeological and hydrological evaluation and hydraulic calculations of the area were done.

 In order to ensure the stability of the landslide slope in Erekle II Street in city of Sighnaghi, a drainage system to discharge the ground waters was designed, and a ditch by considering the calculations of the relevant hydrological and hydraulic properties was also designed.

Implementation of the investment in the rehabilitation of irrigation systems in Kaspi District of Georgia, as well as in the construction of the Tedzami reservoir, allows for 20 years of operation of this complex reclamation facilities to accumulate at internal rate of return of investment (IRR)of 12%, the net present value (NPV) in the amount of 37.92 million GEL. Due to the fact that according to the calculation of performance indicators laid achievement of design yield of irrigated land almost in the third year of operation of reclamation complex, storage of 5-10% of agricultural production makes investments not effective in the construction of the object.         

The risks of failure to achieve design efficiency greatly smoothed the effect of social    investment. Implementation of design solutions allows the full irrigation of crops, hundreds of farmers receive guaranteed sustainable yields, to participate actively in the development of competitive market relations.

The article deals with the issue of the depreciation of productive funds of reclamation maintenance organizations of Georgia. With the transition to a market economy it has become an objective necessity to implement the Independent investment policy according to water management organizations. The organizations injected the accumulated depreciation fund and finally got the opportunity to plan and implement independently the changes the worn-out parts into the new, more effective machinery and equipment. In that connection, the issue about choosing the calculation method is getting more important.                                         

 From our point of view, the most interesting is method for annuities, when the amortization funds are accumulated in the special reserve to be used later on buying some new machinery, mechanisms, equipment and new buildings instead of old ones. Moreover, this amount will accrue interest on reserve.

Mulching issues are discussed in the article. It’s estimated that mulching is an important method for maintaining moisture in soil and reducing the weed control costs. Introduction of organic mulch improves soil structure and enriches its organic matter.

This article discusses issues related to improving the efficiency of water use in irrigated agriculture of Georgia. Established the ineffectiveness of the current system of payment for crop irrigation. An analysis of the existing systems in the world pricing of irrigation water. Particular attention is paid to the operation of irrigation systems in modern condition. The necessity of the functioning of farmers’ associations.

n the article is considered tariffication issues of irrigation water, there is presented short description of the tariffication systems exiting in the World, among them tariffication based on the social-economical criteria, tariffication according to productivity and average cost of water.

 There is considered possibility of binary tariffication using, there are its values.

In the World practice is in the use various methods of amortization accrual and residual balance cost determination. In the article is considered depreciation method of main fundsresidual values, among them method of balance value depreciation with permanent share, method of accumulated reserves and annuity. There is grouping of main funds according of Georgian laws by amortization norms.

In the article has been established economical effectively of modern method against soil erosion by using of geo mat “Luffaeromat” and in case of multi-cultural (nut plantation) cultivation. It has been calculated charge of implementation works and discounted income received a 20-year period from the restored slope (2017-2036). In this cases discounted income for 2036 reached to 117610 GEL on the 1 ha.

The paper discusse quantitative evaluation of the share of input in the efficiency of agriculture in Georgia. There is reviewed dependence of the effectiveness of irrigation on the natural-climatic conditions in the particular regions of the country.

The questions of world practice of fixing price are considered on water. The concepts of economic value of water resources are certain. The methods of fixing price are described on waters. For the different types of water consumption there are numerous of cost estimation: marginal cost, average cost and total economic worth.

At present, methods have been developed for solving the problem of the distribution of the water resources of the South Caucasus, stabilizing the ecological situation in the territory under consideration. When implementing this problem, integrated water resources management methods can be effective means of reducing the scarcity of water resources. It is with this approach to the problem of using water resources that one can not be afraid of a water crisis.

 The article gives determination of the social-economic system, shows the essence of the methodology for systemic investigation of social- economic processes, reviews the integral parts (subsystems) and basic industry practices of social- economic systems of agricultural organizations. There are given goals and tasks of social-economic systems with agricultural direction in market conditions, outlined the ways of their realization. The article gives determination of the social-economic system, shows the essence of the methodology for systemic investigation of social- economic processes, reviews the integral parts (subsystems) and basic industry practices of social- economic systems of agricultural organizations. There are given goals and tasks of social-economic systems with agricultural direction in market conditions, outlined the ways of their realization. 

The article involves brief history of flumes implementation and assimilation, explains their advantages for conditions in Georgia in comparison with other types of channels. There is reviewed the issue of flumes conductivity reduction in the process of operation compared with the design calculation, that is caused by uneven sagging of supports (stands and slabs) and related changes of inclination of certain flumes. There is explained the reason of water overflow from the flumes, related with increasing of the flow depth in the next flume due to the new, reduced inclination. There are given recommendations for elimination of the reasons for differential sagging of the supports, as in the process of construction, so in the process of operation.

The present article describes existing methods of calculating a drainage runoff module, their values are compared with those of the countries of Europe, USA and Russia. Parallels are drawn between the climatic and soil conditions of the Great Britain and the Kolkheti lowland. In view of the above and according to the experimental data the following conclusion was made implying that a value of the drainage runoff design module for the conditions of the Kolkheti lowland requires to be increased. 

The article provides a classification of the cost of irrigation water. The estimated cost of working time for the production of maintenance work. The calculation of the cost of current and restoration repairs of ameliorative infrastructure has been submitted. The method of calculating the rates for water supply is given.

The climatic conditions of Georgia largely dictate the need for irrigation of crops. The article presents the results of calculations of the share of irrigation land in the efficiency of agricultural production, its quantitative dependence on the climatic conditions of the region. The calculation of the effectiveness of capital investments in the rehabilitation (restoration) of reclamation systems is carried out on the example of the Kaspi administrative region of the country. The implementation of investments, taking into account the share of the contribution of irrigation to the efficiency of agricultural production with an internal rate of return on investment (IRR) of 60%, accumulates the net present value (NPV) of 37.92 million GEL. Implementation of project decisions will ensure full-fledged irrigation of crops, which in turn will create conditions for the formation of competitive market relations in the country's agriculture

The article reviews so called internal network operation organizational scheme of the irrigation systems though amalgamation of farmers. It briefly describes specificity of creation and functioning of these amalgamations and gives positive sides of functioning of such amalgamations.

Reservoirs are one of the most important elements of water management systems that ensure the accumulation and the most efficient use of water resources. However, reservoirs, together with a significant positive effect, carry the threat of catastrophic destruction, leading to human casualties, loss of agricultural land, housing and transport infrastructure. The article provides an expert assessment of the natural conditions of the existing reservoirs in Georgia, which determine the possibility of accidents and disasters. Accident hazard indicators are selected as follows: reservoir bed and method of filling it; hypsometric and relief characteristics of the area; seism city of the area; dam material; atmospheric precipitation (annual and daily maximum precipitation). The data was normalized by the linear transformation method. The predicted values of the emergency rate of the country's water storage systems have been established.

Water resources management is becoming one of the most pressing problems in the system of optimal planning of economic activities. One of the most effective tools for optimizing water resources management is mathematical modeling based on the system analysis methodology.

The influence of factors of intensification of agricultural production on irrigated lands is considered. In order to establish the quantitative characteristics of the influence of each of the studied factors (capital equipment, chemicalization and reclamation), their numerical values were calculated and, accordingly, the production function was constructed.

Determining the tariff for irrigation water supply is not 0nly ekonomik task, but also socio-politikal one.n those countries where the of water accounting is low and, accordingly, principles of modern management do not work, water management organizations do not receive the necessary income from water distribution to cover the financial costs of operating ameliorative systems. In the irrigation conditions of Georgia, where, depending on the climatic conditions of the year, the need for irrigation water is unstable, the factor of reliable financing operational work is of fundamental importance. This problem can be solved by introducing a binary tariff into the irrigation water billing practice, which is a modification of the tariff formed on the basis of calculating the cost of irrigation water supply. The tariff consists of per hectare (per 1 hectare of irrigated area) and per cubic meter (per 1 m³ of supplied water) rates.

Differentiated according to natural and climatic conditions and the level of capital equipment of reclamation systems, tariffs for irrigation water supply services significantly exceed the current unified tariff for Georgia. A significant increase in tariffs will provide an opportunity for water management organizations to carry out full-fledged productions of maintenance work, significantly increase the reliability of the reclamation systems and, accordingly, the reliability of irrigation water supply.  

While designing drainage systems and storm water drainage networks, the estimated frequency of the intensity of atmospheric precipitation are assumed empirically, taking into consideration years-long operation of such structures. The issue of determination of the estimated frequency of the atmospheric precipitations’ intensity, based on the objective criteria, is reviewed in the article. For the settlements chosen at random (three for drainage networks and three for the storm water drainage network), with different characters of the curve of the estimated frequency of precipitation intensity, calculation was carried out and the unitary cost was determined. Based on these data the graphs of the precipitation dependence of the intensity on the frequency and dependence of the unitary price on the intensity of precipitations are plotted. Combination of the graphs gives the estimated value of frequency.

The article considers the issue of irrigation water charging, shows the dynamics of changes in irrigated areas of Georgia at the beginning of the 21st century and the amount of water spent on irrigation, explains the probable reasons for excessive water consumption. A brief description of the charging systems used in world practice is given, among them: based on socio-political criteria, on the "yield" and the average cost of water, their positive and negative sides are explained. The conditions for applying binary charging and determining the values included in it are described. The example shows the advantage of calculating one of the components of fixed expenses - depreciation of fixed assets using annuities, compared to other methods. "Yield" and the average cost of water, their positive and negative aspects are explained.

The paper discusses the peculiarities of sedimentary soils of the Kolkheti lowland, explains the mechanism of their sedimentation and its causes, and provides a schematic map of the soils of this region. As a result of long-term observations and study of the material on the bonded soils of different regions of the world, it has been established that the strongly compacted heavy soils of Kolkheti can be attributed to the hydromorphic Montmorillonite bond soils. It has been established that the permeation process is mainly related to the hydration of soil colloids; however, when such soil dries, an inverse process is observed - the formation of cracks. The alternation of permeation processes does not practically affect the soil permeation ability; Relevant graphs are presented here, which show the process of different soils permeation and their differences with non-permeable soils; To assess the physical and chemical condition of soils, it is recommended to introduce a universal criterion in terms of specific surface energy; Measures to improve the characteristics of permeable soils are set: increase the content of organic matter in the soil, introduction of phosphates (in the form of phosphate-gypsum), pesticides and others.

This article discusses the influence of the agricultural climate and the soil conditions of a arrigation regime. In three regions, such as Kvemo Kartli, Shida Kartli and Mtskhet-Mtianeti, two villages were chosen for this purpose based on different soil conditions. The climate rates of villeges were defined by the mobile minimum power station. In each village, samples of the soil that have been tested for laboratory were collected. The value of analytically defined expenses was determined during the experiment. The relative moisture of the water used to control the natural water was measured by the relative humidity of the soil to begin with watering.

As a result of the experiment, it was established that, along with agro-climate factors, the condition of the soil should be considered when implementing relevant recommendations.

Deformations of ditch channels are the main obstacle to their use. The work is devoted to the use of reinforced concrete channels for irrigation systems. The advantages of the arrangement of ditch channels for the uneven terrain conditions of Georgia are discussed. It is explained that their deformations – falling from the supports – can be caused either by violation of the technological scheme of the grooved channel arrangement during construction (repair) and by using cement solution instead of sealing with elastic linings of the edges, or by constructional reasons - the uneven effect of temperature deformation (extension-and-shortening) on different ends of the groove in the conditions of swaying of the channels. The different effects of this reason on non-uniform (double-sided smooth-bottomed) and uniform (parabolic, tubular) grooves are explained. A natural study of the issue – the influence of the type and construction of the supports on the stability of the channel is given. The article provides ways to prevent this from happening.

Accidents of hydraulic engineering facilities, associated with human casualties, disruption of normal living conditions, destruction of material values, in most cases are caused by the manifestation of natural forces of nature.

The article gives examples of catastrophic floods in the world for the last 10 years; the impact of natural phenomena (floods) on reservoir hydraulic engineering objects is considered, the sectors of national economy whose damage is maximum are listed: the hydraulic engineering object itself, industry, agriculture, energy, utilities. The methodology of calculation of economic damage caused by floods is offered. The estimation of economic efficiency of preventive measures to reduce damage at hydraulic engineering objects is given.

Criteria of economic efficiency of capital investments in protective measures against the manifestations of natural phenomena and, in particular, floods are net present effect and internal rate of return. For example, the calculation was carried out for the Zhinvali reservoir, the rational management of which allows to increase the operational life by at least twenty years.

The article considers the issue of determining the reclamation indicators of soils in the irrigation zone

of the Caspian and Mtskheta municipalities of the Shida Kartl Plain in order to clarify the irrigation regime.

The soils of the considered zone, from the reclamation point of view, are grouped into seven categories

based on the relevant experimental data. For each category, the values of ameliorative indicators are given.

Based on the data obtained, the irrigation rate was determined. The minimum value of soil moisture, which

determines the start date of the next irrigation, has been established.

As of today, there is no universally acknowledged radical engineering structure to fight mudflows and

landslides; nor is there a unified approach to calculation of the damage caused by them. The article proposes

the methodology for calculation of the economic damage associated with these spontaneous natural

calamities. There is given the assessment of the economic efficiency of the measures directed to reduction of

the damage caused by mudflows and landslides.

In contemporary conditions the existing Program for Rehabilitation of Irrigation Systems is widely spread in Georgia. In the project tasks, as a rule, notwithstanding the natural-climatic conditions and without justification of the necessity, there is requested reviewing of possibility to replace the gravity irrigation by drip irrigation. The article is dedicated to the appropriateness of such replacement in the course of rehabilitation of irrigation systems. To identify economic efficiency of such requirement, there has been reviewed one of the distributors of the general irrigation system, where the gravity irrigation is to be replaced by drip irrigation. For the both methods there are determined capital and operating costs and there are calculated the values of Pure Net Variation. It has been found that such replacement during the rehabilitation conditions is economically unjustified and is appropriate only when water shortage in a feeding source.

Reduction of soil erosion is one of the main issues of modern engineering ecology. It should be noted that this problem is caused not only by natural factors, but also by peculiarities of some irrigation methods. The article considers the issue of erosion of earthen channels of temporary irrigation network under gravity irrigation. On the temporary irrigation network of three villages in Shida Kartli region of Georgia the amount of erosion was experimentally determined and its dependence on network parameters and soil conditions was established. As a result of this work, to reduce soil erosion (scouring), it is recommended to install canals with compacted crosssection. 

Global climate change has caused sharp increasing of natural calamities, including floods. In the course of recent period, over the entire world, every year there are occurring tens of cases of disastrous floods and waterflows characterized by damages worth of several millions and human losses. The issue of forecasting waterflows and floods, in general, is discussed in the article. There are given basic differentiating features-characteristics existing between spring floods and rain-caused waterflows. The methodology of forecasting related decision-making based on the Statistical Fuzzy Analysis is developed at Ivane Javakhishvili Tbilisi State University, which methodology can be used for flood forecasting. The methodology consists of two stages. At the first stage one and the same prognostic event is assessed using three methods, which allow to make independent forecast. At the second stage, according to the mentioned forecast, the final decision is made. The factors suggested for application of this methodology for flood forecasting are directly related to the climatic parameters of the territory and the state of a river bed and lower terrace. The basic goal of the methodology suggested for flood forecasting is timely reporting on an anticipated disaster..