Tài liệu International Workshop on Environmental and Economic Accounting - COMPILATION OF RESOURCES ACCOUNTS (SELECTED CASE STUDIES) pdf

International Workshop on Environmental and Economic Accounting 18-22 September 2000, Manila, Philippines SESSION COMPILATION OF RESOURCES ACCOUNTS (SELECTED CASE STUDIES) Title Concepts, Sources and Methods for Australia’s Water Account Author Christina Jackson Environment and Energy Statistics Australian Bureau of Statistics Presenter Bob Harrison Environment and Energy Statistics Australian Bureau of Statistics Country Australia Concepts, sources and methods for Australia's water account Christina Jackson, Environment and Energy Statistics Section, Australian Bureau of Statistics Background Most of Australia's land mass is classed as arid or semi-arid, with median rainfall of less than 600mm for 80% of the continent High rates of evaporation and relatively low relief result in low percentage runoff from precipitation that result in streamflow and groundwater Australia also has a high climatic variability (both spatially and temporally) These features explain why Australia has the highest level of water storage per capita of any nation in the world (SoE 1996) Surface water and groundwater resources in Australia are diverse in nature and figures and show Australia's 12 drainage divisions (245 river basins) and 61 groundwater provinces Irrigation for agriculture is by far the largest use of water, representing about 70% of a Australia's water use annually Many of Australia's rivers are becoming increasingly degraded, as evidenced by blue-green algal blooms, declining fish stocks, high levels of salinity or acidity, the loss of wetlands, and significantly reduced environmental flows (SoE 1996) Initiatives to improve this situation include a wide range of water reforms designed to address issues such as: • inadequate pricing mechanisms, • over-allocation of water resources and • the implementation of environmental flows to improve and maintain river health Figure River basins in Australia Figure Groundwater provinces in Australia Overview of environmental accounts 2.1 Development within Australia Work on physical accounting has arisen from the desire to assess the sustainability of economic activities and their interaction on the depletion and degradation of natural resources Environmental accounting provides an integrated information system to link environmental and resource issues to economic data sets such as Australia's National Accounts This facilitates policy-making and analysis of the interaction between environmentally sound and sustainable economic growth and development Both on the international level and within Australia there has been a policy shift from economic, social and environmental policy as separate issues to one of integrated sustainable development Linking changes in the environment and resource base with measurements of activity of change At a national level, environmental accounting is an objective through the National Strategy for Ecologically Sustainable Development (ESD 1992) The principle behind ESD is that the way of life depends on a range of natural assets - air, soil, water, forests and other biological systems and assets must be safeguarded The Strategy specifically encourages the development of environmental accounting within the Australian National Accounts For a number of years the ABS has been pursuing the challenge of developing elements of environmental accounting as an integrated information system for Australia that links environmental and resource issues to the well established and much used set of national accounts Such a task has many aspects and full completion is a long term objective To date a number of experimental environmental accounting projects have been developed by the ABS including: energy, mineral, fish and water accounts, environment protection expenditure and national balance sheets In May 2000 the first edition of the Water Account for Australia was released it was developed for 1993-94 to 1996-97 financial years 2.2 Conceptual framework Environmental accounts can facilitate an integrated approach to a range of issues these include: • a broader assessment of the consequences of economic growth; • the contribution of sectors to particular environmental problems; and • sectoral implications of environmental policy measures (for example, regulation, charges and incentives) The advantage of an environmental account is that by linking together physical data and monetary data in a consistent framework it is possible to undertake scenario modelling Issues that could be modelled include assessing the efficiencies in different sectors of the economy and the environment and resource implications of structural change The water account was developed with reference to Australian objectives and priorities and the physical characteristics of Australia's water resources It provided a mechanism to tie together data from different sources into one consolidated information set It is then possible to link physical data to economic data sets such as Australia's National Accounts or to other natural resource data sets The System of National Accounts (SNA) supports policy making at a national level, however, historically the methods have had little regard for environmental matters The main aim of environmental accounting is to assess the sustainability of economic activities and economic growth by quantifying the depletion and degradation of a natural resource An environmental account provides an information system which links the economic activities and uses of a resource to changes in the natural resource base Data analysis for the water account tends to follow the guidelines described in Integrated Environmental and Economic Accounting - SEEA (UN, 1993a), a complement to the System of National Accounts 1993 (UN, 1993b) Supply and use tables provide the framework to link core components of the National Accounts to physical flow accounts Environmental accounts extend the boundaries of the System of National Accounts (SNA) framework to include environmental resources which occur outside the production and asset boundaries typically measured in such an analysis Figure illustrates the relationship between environmental accounts and national accounts Stock measures have been developed for water resources and they are an example of extending the SNA definition of the production and asset boundaries Typically environmental assets provide important goods and/or services to the economy, e.g timber, or waste assimilation The environmental asset accounts include the level of resources available and changes within a given time period due to both human and natural causes Figure The Australian System of Environmental Accounts in relation to National Accounts Consumption of fixed captital Financial & produced assets Environmental losses & assimilation Wastes & residuals Economic activity Gross fixed capital formation Material input Environmental stock Environmental activity Growth $ Environmental Protection Accounts includes only transactions relevant to environmental protection $ I-O tables Physical I-O tables Physical Natural Resource Accounts includes both economic and environmental assets $ Financial & Produced Assets Accounts $ Natural Resource Accounts Balance sheets includes economic assets only Stock tables for Water 3.1 Framework The water stock tables accounting framework does not follow the traditional stock table format detailed in SEEA Instead a perspective of Australia's water resources has been developed using the SEEA framework (UN 1993a) and considers the physical characteristics that influence the nature of water resources in Australia As water resources are being constantly renewed a clear distinction is required between the capacity of a system and its potential yield The potential yield of the system is dependent upon long term climatic variability, and not solely upon the system capacity The influence of climatic variability on water resources is fundamental in Australia for the following reasons: • Annual accounting is unsuitable to characterise the performance of systems such as water resources in Australia which have long response times • Climatic variability is unique to Australia where non-annual climate variations influence water resources The ENSO (El Nino Southern Oscillation) effect controls the cyclic climatic variations which range from to years in length • The standard accounting strategy of opening and closing stocks over an annual period is unsuitable for water resources in Australia To overcome these problems, the basic SEEA framework was modified to redefine 'opening' and 'closing' stocks as measurements taken at different points in time, instead of 'opening' and 'closing' stocks based on changes over a one year period The stock tables consist of tables which measure the long term availability of water resources (measured at different points in time) and an annual water pathways analysis Due to the limited availability of relevant data the example tables shown below detail only results for the state of Victoria Definitions of the terminology are found in Appendix 3.2 Water asset tables An asset table intends to show long term availability of water resources in a particular river basin or groundwater province This assessment is made at particular points in time so a timeseries of asset tables can in theory be compared to demonstrate the changes in resources through time and the long term availability of resources 3.2.1 Surface water asset tables A surface water asset table includes the following volumetric measures: • water allocated for economic use • water allocated for environmental use; • volume of unallocated resources; and • mean annual runoff Average annual water resources will give an indication of the long term availability of water A limitation of this approach for surface water allocated for environmental purposes is that many allocations for river basins are not derived on a megalitres per year basis but on passing flows at particular times during the year Passing flow allocations for environmental purposes will not be identified by this approach 3.2.2 Groundwater asset table Due to the fact that the volume of water stored in groundwater systems is not well known groundwater assets were measured as the sustainable yield rather than as the volume in storage The volume in storage is an estimate and not necessarily fully available for use A past review of Australia's water resource was undertaken in 1985 (AWRC 1987) in which groundwater resources were defined as "Total Divertible Resource" (TDR) In recent years there has been a move away from this measure to one of "Sustainable Yield" (SY) There is currently substantial discussion to define Sustainable Yield as a result of the Council of Australian Government's (COAG) Water Reform agenda Groundwater assets are categorised according to salinity which indicate some potential use limitations of the resource Good quality water for human use typically has a salinity (total dissolved solids) of less than 500 mg/L, with an upper limit of 1,500 mg/L (also the limit for crop irrigation) Water for livestock is preferably in the lower ranges, but some salt tolerant livestock can tolerate water up to 15,000 mg/L For coarse industrial processes, such as mineral ore processing, the upper limit may be much higher By comparison, seawater has a concentration of about 35,000 mg/L 3.2.3 Results Due to limited data availability asset tables were only developed for the state of Victoria Table details surface water assets in 1985 and 1998 and the volume changes between the reference years Table shows the 1985 categorisation of groundwater resources based on the TDR definition and the framework for the 1998 assessment No appropriate data was available for 1998 and the limited groundwater data for 1998 was available only for groundwater management areas (GMA) Due to this fact and the change in definition from TDR to SY the 1985 and 1998 could not be directly compared Table shows an example of the 1998 data Table Surface water asset table for part of Victoria River River basin basin no name 401 402 403 404 405 406 407 408 414 415 Upper Murray Kiewa Ovens Broken Goulburn Campaspe Loddon Avoca Mallee Wimmera 401 402 403 404 405 406 407 408 414 415 Upper Murray Kiewa Ovens Broken Goulburn Campaspe Loddon Avoca Mallee Wimmera 401 402 403 404 405 406 407 408 414 415 Upper Murray Kiewa Ovens Broken Goulburn Campaspe Loddon Avoca Mallee Wimmera Economic Environmental Environmental Total assets allocated(a) allocated(b) (MAR)(c) unallocated GL GL GL GL 1985 Assessment 1,600 — 1,200 2,800 10 — 695 705 100 — 1,520 1,620 100 — 225 325 1,780 — 1,260 3,040 110 — 170 280 100 — 151 251 — 80 85 — — — — 110 — 263 373 1998 Assessment 1399 — 1401 2800 14 — 691 705 91 — 1529 1620 153 — 140 293 2005 80 1231 3317 135 — 180 315 161 28 74 263 — 81 85 48 — -48 — 178 11 184 373 Volume Changes(e) –201.0 — 201 — 3.7 — –3.7 — –9.1 — 9.1 — 53 — –85.0 –32.0 225.2 80 –28.2 277 24.9 — 10.1 35 61.4 27.6 –77.0 12 –1.1 — 1.1 — 47.9 — –47.9 — 67.8 11 –78.7 — (a) Average annual volume allocated for economic activity It is the measure of the average volume of water that could be diverted from a river basin each year on a sustained basis for economic activity (b) Average volume of water required in a basin each year for environmental flows or to sustain prevailing environmental conditions (c) Volume unallocated for a specific purpose (difference between MAR and other allocations) (d) Total resources are taken as mean annual runoff (MAR) see glossary for definition (e) Volume changes occur due to a reassessment of resources or changes in methodology Table Groundwater assets in Victoria Province no Province 7F 8S 9S 10S 11S 12S 14S 7F 8S 9S 10S 11S 12S 14S 7F 8S 9S 10S 11S 12S 14S TDR by salinity category(a) Fresh Marginal Brackish Saline Total GL GL GL GL GL 1985 Assessment Lachlan (Vic.) 39.8 26.8 19.2 — 85.8 Gippsland 286.8 37.9 — — 324.7 Western Port 3.9 17.7 — — 21.6 S Port Phillip — 2.1 2.9 0.4 5.4 11S Otway Highlands 0.5 — — — 0.5 110 175.3 12.4 — 297.7 S Otway 14S Murray (Vic.) 36.5 79.4 88.8 31.9 236.6 Victoria Total 477.5 339.2 123.3 32.3 972.3 1998 Assessment Lachlan (Vic.) n/a n/a n/a n/a n/a Gippsland n/a n/a n/a n/a n/a Western Port n/a n/a n/a n/a n/a S Port Phillip n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 11S Otway Highlands S Otway n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 14S Murray (Vic.) Victoria Total n/a n/a n/a n/a n/a Volume changes Lachlan (Vic.) n/a n/a n/a n/a n/a Gippsland n/a n/a n/a n/a n/a Western Port n/a n/a n/a n/a n/a S Port Phillip n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a 11S Otway Highlands S Otway n/a n/a n/a n/a n/a 14S Murray (Vic.) n/a n/a n/a n/a n/a Victoria Total n/a n/a n/a n/a n/a (a) Measures both major and minor groundwater resources, salinity is total dissolved solids Fresh: 5,000 mg/L Table Groundwater assets in 1998 Province 8S Gippsland 8S Gippsland 8S Gippsland 8S Gippsland 8S Gippsland 8S Gippsland 8S Gippsland Sustainable yield by salinity category(a) Fresh Marginal Brackish Saline Total GL GL GL GL GL Moe — 8.2 — — 8.2 Seacombe — — — Sale — 13 — — 13 Denison — 12 — 12 Wa De Lock Zones 1, & — 31.9 — — 31.9 — 9.7 — — 9.7 Wy Yung Zones 1, & Unincorporated Areas n.a n.a n.a n.a n.a GMA (b) (a) Measures both major and minor groundwater resources, salinity is total dissolved solids Fresh: 5,000 mg/L (b) Groundwater management areas cover specific surface area and aquifer systems within provinces 3.2.4 Water quality The groundwater asset table includes measures for salinity However it is difficult to aggregate water quality point measures to be representative of a large region such as a drainage division or nationally because regional variability in quality would be lost Variations in water quality can occur for a number of reasons: • season; • flow; • time of day; • variation in measurement techniques; • variations in sampling strategy; and • variations in location No attempt has been made to integrate water quality for the surface water asset tables 3.3 Water pathways analysis Table shows the structure of a water balance describing the inflows, changes in quantities of water resources and outflows Ideally, it would be valuable to compile a water balance for Australia, by river basin, however, it is difficult to collect data water consumption data at that level of detail In ABS (2000) the water balance was developed for the state of Victoria and not for individual river basins within the state Table Water pathways analysis for Victoria, 1996-97 in Gigalitres A Inflows A.1 Precipitation A.2 Natural inflow from adjacent basins A.3 Total inflows (A.1+A.2) B Net Anthropogenic Changes B.1 Net Economic Changes i Water used for economic purposes ii Return flow discharges B.2 Water transfers i Water transfers into the measurement region ii Water transfers from the measurement region B.3 Total net anthropogenic changes (+/-B.1+/-B.2) C Net Changes in Storage C.1 Changes in the storage in lakes and dams C.2 Net groundwater recharge C.3 Other volume changes n.e.c C.4 Total net changes in storage (+/-C.1+/-C.2+/-C.3) D Outflows D.1 Evapotranspiration D.2 Basin outflow (mean annual runoff) D.3 Total outflows (D.1+D.2) 1996-97 GL 134,269 134,269 5,183 9,929 4,746 0.02 0.08 0.06 5,183 1,015 n/a 50,408 51,423 60,243 19,450 79,693 Inflows (from precipitation) vary from year to year, however, outflows are given as the long term mean and are therefore constant throughout the years In ABS (2000) the long term mean for evapotranspiration and basin outflow were used because no other data were available Net anthropogenic changes parameter considers the volume of water diverted for economic use from surface and groundwater resources and subsequent return flows The water use and discharge data links to the flow tables (described in Section 4) The changes in the storage of lakes and dams is measured as the difference in the amount of storage at the start and end of the reference period 3.4 Data sources Data for the stock tables are based primarily on state government information There is currently a national program being undertaken to update a range of land and water resource information in Australia called the National Land and Water Resources Audit This audit will provide useful data for future developments of water asset tables in Australia There is a need to ensure that definitions of the resource remain relatively constant to allow a meaningful comparison between years For the annual water pathways analysis presented in ABS (2000), resource data was collected data can be sourced from the relevant state government agency; precipitation and evapotranspiration data from the Bureau of Meteorology (BoM), interstate water transfer data from the Murray Darling Basin Commission (MDBC) and water use data obtained directly from water authorities in Victoria Flow tables for water 4.1 Framework The framework of the water flow tables follows guidelines in SEEA (UN 1993a), a complement of the SNA93 (UN 1993b) Supply and use tables provide the framework to link core components of the National Accounts to physical flow accounts The aim of the data collection activities for the flow table component of the water account project was not to duplicate existing data collection activities but to tie together regional and state water resource data into a single system of the economy wide impact of water resource management and usage across Australia The supply and use tables are components of the Input-Output (I-O) framework This framework is used widely by the ABS for economic analysis and is based on SNA93 (UNb 1993) The I-O framework describes the movement of water from the environment as input into economic activity, as well as the return flow from production and consumption activities back into the environment The water flow tables will indicate the physical amount of water (Megalitres) supplied from the environment and water authorities for use by industry, households, government and the amount available for return flow to the environment The supply table illustrates who is supplying water for use and the use table shows who is using water The tables have been compiled using input-output concepts and classifications The industry classification which has been used is based on the Input Output Broad Industry Group (IOBIG) classification The agriculture classification does not fit well with the available data, and it was split based on the significant commodities within the agricultural • other related information including details of the storage levels, water transfers, infiltration and consumption charges (however comprehensive data was not provided on these topics) Estimates of self-extracted water were determined for private organisations or individuals not covered by a regulatory water authority This involved requesting data (volume and type of use) from relevant state government authorities which hold details of licences and estimated self-extraction of water by relevant individuals and organisations Water suppliers and users were defined and classified to the Australia and New Zealand Standard Industry Classification (ANZSIC) The tables are presented based on the ABS's Input Output Broad Industry Group Classification (IOBIG) The ANZSIC classifications were aligned to the IOBIG classifications 4.6 Data collation and estimation 4.6.1 Water supply and use To ensure consistency and coverage of all water used and supplied across Australia, a range of estimation techniques were used to fill in the gaps for missing data In the absence of detailed water use data for some sectors of the economy water usage coefficients were developed based on employment or production statistics A range of assumptions were made in analysing and collating data from a diverse range of sources Water supply data was fairly straightforward, it was water consumption where the details of who was using water were unknown for some sectors Water usage data was collected from water suppliers who listed top water consumers and this was used as a basis for developing case studies Because total water use and top consumers were known as well as agricultural and domestic use, it was a category called 'unassigned' which needed to be categorised to various industries It was assumed that the 'unassigned' water included water used for commercial and industrial sectors of the economy because the portion used for rural, household and mining purposes had already been separated out The methodology on how these were developed is detailed in Appendix 4.6.2 Effluent reuse Reuse data was obtained from respondents (usually the water supply; sewerage and drainage services industry) Some manufacturing and mining water reuse has been included, however this is not comprehensive, as a number of manufacturers reuse water on-site and it would be time-consuming to collect this data The majority of the reuse data included customer usage information on who was reusing the treated effluent However, some water providers only gave total amount of water which was reused This 'unassigned' reuse was then allocated to an industry based on data sourced from the Agricultural Census where reuse water was stated as being for irrigation or for crops, and reuse data provided by surrounding areas Some state government surveys could fill in the gaps regarding the supply of effluent reuse from the water supply; sewerage and drainage services industry (when data had not been collected directly from that industry) However there is no set pattern for utilising effluent 13 reuse and it was decided not to impute reuse for those respondents unable to provide a volume of effluent supplied for reuse Reuse may occur on a more extensive basis within the manufacturing and mining sector than has been quantified in ABS (2000) In order to determine the total quantity of water reused by manufacturing and mining it would be necessary to survey the whole industry Constant recirculation of water was not included 4.6.3 Regulated discharge Missing sewage treatment plant (STP) discharge data was derived by comparing discharge and population data to derive STP ML/person rate The usage of water by the aquaculture industry and the hydro-electric power generation sector was assumed to occur 100% instream and was accounted for as a supply and discharge by the same industry 4.7 Data quality and reliability Water use and supply originated from a range of sources with a variable degree of consistency and reliability Data suppliers were requested to provide an indication of the reliability of the data provided Table shows the reliability ratings Table Data reliability categories Category A B C D 4.8 Description Based mainly on reliable recorded and surveyed data Based on approximate hydrologic analysis and limited surveys Based largely on reconnaissance data Derived without investigation Australian flow tables for 1996-97 Tables and illustrate the supply and use tables developed for Australia in ABS (2000) for the 1996-97 financial year Supply and use tables were also developed for each State and Territory in Australia Table is important for water resource managers because it shows the net water consumption which is derived from the supply and use tables 14 Table Supply table, Australia, 1996-97 SelfMains Effluent Regulated extracted water reuse discharge GL GL GL GL Environment 68,703 Livestock, pasture, grains and other agriculture Vegetables Sugar Fruit Grapevines Cotton Rice Services to agriculture; hunting and trapping Forestry and fishing Mining 40 49 Meat and dairy products Other food products Beverages, tobacco products Textiles Clothing and footwear Wood and wood products Paper, printing and publishing 48 Petroleum and coal products Chemicals Rubber and plastic products Non-metallic mineral products Basic metals and products 31 Fabricated metal products Transport equipment Other machinery and equipment Miscellaneous manufacturing Electricity and gas 13 47,560 Water supply; sewerage and drainage services 11,507 82 1,782 Construction Wholesale and retail trade Accommodation, cafes and restaurants Transport and storage Finance, property and business services Government administration Education Health and community services Cultural, recreational and personal services Household Total 68,703 11,526 134 49,480 Sector 15 Table Use table, Australia, 1996-97 SelfMains Effluent Regulated Sector extracted water reuse discharge GL GL GL GL Environment 49,480 Livestock, pasture, grains and other agriculture 3,817 4,978 38 Vegetables 373 262 Sugar 947 290 Fruit 387 316 Grapevines 323 326 Cotton 1,310 530 Rice 1,643 Services to agriculture; hunting and trapping 1 Forestry and fishing 12 13 Mining 545 30 42 Meat and dairy products 45 Other food products 10 54 Beverages, tobacco products 18 Textiles 22 Clothing and footwear 46 Wood and wood products 31 26 Paper, printing and publishing 51 73 Petroleum and coal products 12 Chemicals 12 32 Rubber and plastic products Non-metallic mineral products 15 Basic metals and products 62 91 Fabricated metal products 35 Transport equipment Other machinery and equipment 13 Miscellaneous manufacturing 17 Electricity and gas 47,771 58 Water supply; sewerage and drainage services 12,864 350 Construction Wholesale and retail trade 74 Accommodation, cafes and restaurants 36 Transport and storage 47 Finance, property and business services 69 Government administration 51 Education 35 Health and community services 34 Cultural, recreational and personal services 79 64 33 Household 33 1,796 Total 68,703 11,526 134 49,480 16 Table Net water consumption, Australia, 1996-97 Sector Livestock, pasture, grains and other agriculture Vegetables Sugar Fruit Grapevines Cotton Rice Services to agriculture; hunting and trapping Forestry and fishing Mining Meat and dairy products Other food products Beverages, tobacco products Textiles Clothing and footwear Wood and wood products Paper, printing and publishing Petroleum and coal products Chemicals Rubber and plastic products Non-metallic mineral products Basic metals and products Fabricated metal products Transport equipment Other machinery and equipment Miscellaneous manufacturing Electricity and gas Water supply; sewerage and drainage services Construction Wholesale and retail trade Accommodation, cafes and restaurants Transport and storage Finance, property and business services Government administration Education Health and community services Cultural, recreational and personal services Household Total Gigalitres 8,795 635 1,236 704 649 1,841 1,643 17 570 52 64 21 25 51 58 124 13 44 24 153 44 18 22 1,308 1,707 13 75 43 50 69 59 36 34 143 1,829 22,186 Linkage to other data, Australian examples In developing the first edition of the water account it was not possible to compare the physical data directly with monetary data in the input-output framework Currently monetary data relating to the water industry in the input-output tables is based on outdated assumptions and is therefore not directly comparable to physical data Agriculture is a major consumer of water and the split of the monetary data into the relevant agricultural commodities cannot be made Nevertheless the physical data can be compared to a range 17 of useful socio-economic data The following tables and figures detail some of the linkages to other ABS datasets that were possible Table 10 Water use, employment and IGP, 1996-97 Sector Employment Industry gross Net water Exports product (IGP) use '000 Agriculture(a) Services to agriculture, hunting & trapping; Forestry & fishing Mining Manufacturing Electricity and gas Water supply, sewerage and drainage services Selected service industries 302 $m ML 9,121 15 502 973 $m 8,991 39 77 1,021 42 1,721 20,836 63,615 9,733 18,814 570,217 727,737 1,307,834 1,785 17,938 48,494 — 19 5,225 3,955 162,372 1,706,645 463,748 — 1,725 (a) includes dryland and irrigation farming Figure Industry gross product per megalitre used, 1996-97
                   "#$%  ! Table 11 Water use and gross value for irrigated agriculture, Australia, 1996-97 Sector Livestock, pasture, grains and other agriculture Vegetables Sugar Fruit Grapes Cotton Rice Total Gross value Net water use Irrigated area $m ML 2,540 1,119 517 1,027 613 1,128 310 7,254 8,795,428 634,913 1,236,250 703,878 648,574 1,840,624 1,643,306 15,502,973 1,174,687 88,782 173,224 82,316 70,248 314,957 152,367 2,056,580 18 Figure The gross value per megalitre of water used by irrigated agriculture, Australia, 1996-97 "$%  /  /  &   '  ( ) *   + -. ... sustainability of economic activities and their interaction on the depletion and degradation of natural resources Environmental accounting provides an integrated information system to link environmental and. .. for environmental matters The main aim of environmental accounting is to assess the sustainability of economic activities and economic growth by quantifying the depletion and degradation of a... range of issues these include: • a broader assessment of the consequences of economic growth; • the contribution of sectors to particular environmental problems; and • sectoral implications of environmental