Home Articles GIS as an integrating instrument for micro-watershed planning and management

GIS as an integrating instrument for micro-watershed planning and management

J. G. Krishnayya Angira Baruah
MicroTechnologies (I) Ltd, Pune 411037
[email protected]

Introduction
Micro-watershed planning has been conceived and adopted for holistic development of rainfed farming in recent years. Watershed Management is fast becoming a blue print for agricultural development in most parts of the country today. This programme aims at conserving soil and moisture, as well as to put the lands to use according to their capabilities to improve the overall productivity of the catchment. The major objective of the programme is to increase/stabilise production of crops, forage, fruits, fuel and timber in rainfed areas by introduction of improved soil and moisture conservation measures, better crop and rangeland management practices, animal husbandry and afforestation.

The ultimate goal of watershed management is to achieve and maintain a balance between resources development to increase the welfare of the population — and resource conservation to safeguard resources for future exploitation and to maintain ecological diversity – both for ethical reasons and as an assumed prerequisite for the survival of mankind.

Watersheds
Watershed is an area which catches the water from precipitation and then is drained by a river and its tributaries. It is a “resource region” where the eco-system is closely interconnected around a basic resource – water. The watershed or river basin is therefore an ideal management unit.

A micro-watershed, as defined by Bali in 1978, ranges in between 1-10 sq km or 100-1000 hectares.

The conservation measures and treatments would vary from watershed to watershed depending upon their characteristics, e.g. geographical locations, climatic conditions, soil types etc. Generally speaking, water, soil and biomass are considered to be the three most important components in a watershed. Conservation and regeneration of these resources would call for the need to concentrate on the following aspects :

  • Water resource development: The need for water resource development arises in an attempt to mitigate droughts, moderate floods and harvest the run-off water which otherwise goes as waste. The development of water resources mainly include water conservation techniques. This involves increasing the recharge from precipitation with the creation of sub-surface and surface storages which are capable of impounding maximum monsoon rainfall. Storing of harvested run-off water can be accomplished with the help of various water conservation techniques like the construction of masonry weirs, excavation tanks, composite dams etc. This conserved water can be recycled and used at critical stages of crop growth through lifts, open dug wells, borewells etc.
  • Soil Conservation: Soil conservation is by itself the proper land husbandry, which would preserve the land and its fertility on a sustained basis and at the same time increase yields and achieve maximum benefits from such land. Soil erosion is one major problem in the hilly and undulating terrain resulting in low productivity of agricultural land. In order to check this hazard of soil erosion, various conservation measures can be undertaken ranging from narrow based terracing (contour bunding) to bench terracing which would simultaneously include moisture conservation.
  • Development of wastelands: Lands that have one or more limitations of slope, erosion, stoniness, rockiness, shallow soils, wetness, flooding, dry climate etc. make them generally unsuitable for the cultivation of agricultural crops and limit their use largely to pasture, forest, wildlife and recreation. These lands commonly known as “Wastelands” are the source of maximum sedimentation, run-off and floods.

    The denuded forest lands and wastelands are in fact “Wastedlands” as they have a great potential for producing fodder, fuel, fibre, minor fruits and low quality timber. To achieve this, it is necessary to adopt suitable soil and water conservation engineering measures supplemented with proper afforestation techniques, horticultural practices, grassland development etc.

  • Conservation and development of Forests/Vegetation: Vegetation (perennial or annual trees, or shrubs, climbers or grasses) on the site is one of the factors that govern the run-off water which affects erosion. Vegetative control can be one of the essential anti-erosion measures, since it is under human control, unlike rainfall.

    Forests, in general, bring about a long chain of advantages: moderating the local climate, preventing floods, regulating stream flow, sustaining off-season discharge, protecting the soil and enriching it. Thus, an organised maintenance of all perennial vegetation on site is called for.

  • Animal Husbandry/Livestock Management: This would include the population characteristics, type, numbers, quality, distribution, feeding habits etc. of animals as well as birds and marine life. Activities concerning the improvement of livestock management includes pasture and fodder development, improvement of grazing land, stalk feeding and fodder supplies, reduction of grazing pressure on land, improved milk production, other livestock development like sheep, goats, poultry, fisheries, development of small scale/cottage industries for milk products etc.
  • Human Resource Development: Since the ultimate aim of the Watershed Development Programme is to improve the quality of life of the local people, human resource development is one of the most important aspects to be taken care of. It can be approached through awareness and training programmes.

    Data regarding population characteristics, professions, socio-economic conditions, land ownership, tenure, employment status, outside jobs etc. are required for any kind of undertaking in this sector.

| Next | Role of GIS in Micro-Watershed Planning and Management
A GIS is a composite of computer based decision support tools for the integration of spatial data from different sources and for the analysis, manipulation and display of these data. It is therefore, an excellent tool for the management of large bodies of spatially extensive data with all the advantages of a computer environment: precision, consistency and absence of computational error.

This powerful tool holds a very large potential in the field of regional and micro-level spatial planning particularly in micro-watershed planning and management. A GIS can help pull together various types of disparate data such as remote sensing data, census data, records from different administrative bodies, topographical data and field observations to assist researchers, planners, project officers and decision-makers in resource management. Creation of a spatial database is the first step in micro-level planning. This is followed by spatial analysis to help identify problem areas and, finally, the steps towards planning to mitigate problems are taken by marking out action areas. Taking a watershed as the spatial unit of study, appropriate physiographic and morphometric parameters can be taken into account to enable proper micro-watershed management.

Watershed management requires a three-tier management strategy focusing on :
(i) a micro-regional planning approach, (ii) the analysis and appraisal of the biophysical and socio-economic environs and (iii) agro-ecological zoning. The necessity for a micro-regional approach to planning arises primarily because the actual conditions of watersheds vary, depending on the local, biophysical conditions, population pressure and natural resource conditions. ( THAPA, et al. 1992).

Information on existing landuse and landcover, its spatial distribution and changes are essential prerequisites for planning (ANONYMOUS, 1992). Landuse or land-cover changes are critically linked to a combination of natural and human impacts. (TURNER, 1995). An improved understanding of the dynamics of land-use/land-cover changes provide a means for projecting the impacts of landuse. Thus, land-use planning and land management strategies hold the key to development in a region. Geographic Information Systems (GIS) provide an effective tool for analysis of patterns and causes of land-use dynamics and for planning management strategies.

Creating infrastructure to provide support (social) services is a government responsibility and the government has established norms for use in the planning process to cover geographical areas with these services. Whereas, in the plains, the services can reach a greater number of inhabitants; due to (i) a higher density of population and (ii) easy accessibility (few geomorphic impediments); in hilly regions, the placement of these services in tune with the inhabitants’ requirements is more difficult. Sometimes even the geomorphic features create seasonal accessibility (such as a river in spate or a snowy ridge acting as seasonal obstacles). GIS applications have the potential for assessing support service requirements and their placements. This application has advantages over the conventional mechanisms, as multi-criteria analysis is not only feasible but much faster with GIS (MENRIS CASE STUDY Series No.5).

GIS as an Integrating Tool
An important feature of applying Information Technology to the handling of spatial data is the ability to link data sets; that is, to merge and compose different data for the same location. Integration, in a GIS context, is the synthesis of spatial and non-spatial information within the framework of an application. This makes a Geographic Information System an analytical and decision making tool fundamentally different from a paper map. By performing operations across the two sets of information in tandem, a far richer set of questions can be answered and a far broader range of problems can be solved than in systems that handle just attribute or spatial data alone.

The ability of GIS to integrate maps and databases, using the geography as the common feature among them has been extremely effective in the context of Planning development. The attribute database can be analysed by multiple queries, linked to multiple databases related to different projects to arrive at a comprehensive picture of the current scenario in a given area. Since the data (for micro-level planning) would be captured from the lowest end of the administrative system (normally at block level – village-wise), the database can be queried for aggregated results at any of the upper administrative levels viz. District, state and national levels.

A GIS, like any Information System normally includes DBMS functions. However, it differs from conventional DBMS in the sense that every data element in a GIS has to be directly or indirectly associated with a map object — a location on the earth’s surface expressed as co-ordinates with respect to some predefined co-ordinate system. Typical data in spatial form could be on general resources like topography, geology, geomorphology, climate; administrative boundaries like state, district, village, forest range; data on infrastructure like road network, power lines, water lines, sewage lines, locational data in the form of latitudes and longitudes; as well as models like ground water flow, soil productivity, timber growth and soil erosion which can be applied to geographic units. The data in non-spatial form could be the descriptive attributes associated with spatial features like soil type, land use type or socio-economic data.

A case study on the development of a Micro-watershed GIS for planners at the grassroots can be cited as an example, in this context.

Case Study
In a project sponsored by the Ministry of Information Technology (Div’n of Applications of Electronics to Rural and Social Development), the Systems Research Institute is creating a special-purpose vector-based desktop GIS for use at the grassroots, which aims at providing tools that are useful to Micro-watershed planners. This software is basically an integration of five different modules :

VIEW: The viewing module enables the user to select/deselect – different features of a map for viewing, contextually-relevant explanatory text or pictures, or to zoom in and out at different scales on a map, to change colours, to select/deselect information to be displayed on-screen when the cursor lies over a map element, to conduct queries, compute length/area and to print out the map.

EDIT: This is basically for a sophisticated user skilled in map-editing. The user will be asked to type in a password to allow him an access to the editing module. This would include map-inputting capability (read-in of a scanned or digitised map); optional input of height information and development of contours, slope and aspect maps; drainage pattern development; volume computation for proposed water storages, land capability classification, creation of proposed landuse maps, etc. The editing capabilities include search – allows one to search for an object on the map, translation of an object in X & Y direction, object creation of different types, object geometry modification, colouring of objects, creation of buffer zones, etc.

DATABASE: This module consists of the software that records, retrieves and manipulates data concerning sociological information, resource information, historical data /normative data and reports/graphical output.

ANALYSIS: This would enable the user to perform different types of analysis — both spatial and computational, e.g. delineating micro-watersheds from a drainage map, stream ordering, drainage density, calculating maximum basin relief, volume computation for proposed water storages, what-if analysis etc. It also includes hydrological models comprising of different engineering structures for soil and moisture conservation, and water harvesting structures.

HELP: The help module contains the user guide, texts, reference documents and tutorials.

This software is being built using the GeoConcept GIS engine, with Visual Basic. The system will be loaded in a CD (along with texts and reference documents, a user guide and tutorials) and will be distributed by the Ministry of Information Technology in the public domain – i.e. at very low cost. Special efforts are being made to create an extremely friendly user-interface.

The tool is being developed in collaboration with three other organisations – Society for Rural Industrialisation, Ranchi (SRIR); PROGRESS Group, Hyderabad (PROGH) and National Centre for Human Settlements and Environment, Bhopal (NCHSE). The GIS will interface their Foxbase, Access, Excel, etc. files and VB programmes while also providing a general-purpose ODBC database connectivity.

The Alpha-test version of this system is currently ready, and the Beta-test versions are expected before the summer of 2001.
Selecting a GIS solution
Apart from the its capability to acquire, store, analyse and display geographic data, a good GIS should allow for the exchange of map data and attribute data with different applications, the rapid access to underlying information, simple communication with external applications, and investigation, interrogation and calculation in the simplest possible ways. Other important properties for a GIS to be used in India are: (a) COST; (b) User-modifiability through macros (so-called user-programmability); (c) User-friendliness both in the user-interface and in the underlying logic of the system; (d) smooth transition from one platform to another (not merely compatibility).

GIS Psackages-A Survey
There are a considerable number of GIS packages available in the market. Indigenous GIS packages are finding way into many user applications and separate niche market segments are identifiable for these. However, overseas GIS packages will, for a variety of reasons continue to have the lion’s share of the market. Some of the popular ones are:

  • Arc/Info GIS (see also the note below on ArcView): from the Environmental Systems Research Institute (ERSI), Redlands, CA, USA,
  • ArcView, also from ESRI
  • MapInfo (from MapInfo Corp, Troy, NY, USA)
  • WinGIS (from Progis Corp, Graz Austria

GeoConcept (from GeoConcept SA, Paris 13), was designed and developed in France in 1970-71, and is the first PC GIS to be designed from the ground up using the Object-oriented paradigm. This has given it tremendous stability as well as easy expandability. It has an extremely small footprint, which also makes it more nimble. This mapping software reads and writes all GIS vector map data formats. It also has an optimised native raster format, which can handle very large compressed raster maps and display them instantaneously. A variety of standard (image) raster formats can be read, all of which can be fully geo-referenced and ‘stretched’ if necessary to match the underlying grid. On the attribute data side, GeoConcept has special drivers for Oracle and Access, as well as ODBC drivers allowing the import and export of alphanumeric data in the other rdbms systems and SQL languages. A family of Add-Ons is available for 3-D work, Image Analysis, Postscript quality printing, etc.

Formulated as a hierarchical structural model, GeoConcept is capable of managing a very large number (millions) of map objects. It immediately displays the entire data about that object on double clicking on a particular object on the map. In fact selected data on every map-object can be popped up on screen just by passing the cursor over that object! One can perform thematic analysis involving one or more variables, correlating the various elements and fine-tuning the resultant graphical display. Both geographic and numeric queries can be formulated using ordinary language even when the requirements are complex. A multitude of Queries (regarding locations or regarding attribute values) can be formulated and stored for future use, as can created Views or Thematic displays. Variables in the GeoConcept database can be defined in terms of other (static) Variables (using logical, numerical or string functions); their values get automatically updated when the latter change.

The different versions of GeoConcept are 100% compatible – Stand-alone; Client-server; and even the Internet-server version. This itself is a big help to the user who does not have to remember — or translate between — different protocols. There is a Free Viewer available, in addition, which enables the distributed viewing of maps created in GeoConcept.

Upto 32,000 fields of attribute data (including pictures and graphics) can be stored with (and for) each mapdata element. (Control is also stored with the mapdata over what can be seen – and what is invisible – at (12) different levels of zooming, how it is represented, with which marker, linestyle, colour or typeface, etc.) All this is reflected also when one uses the Free Viewer.

GeoConcept is self-contained: the basic system includes complete Digitising and Map-editing capability (including polygon intersections), as well as the ability to do heads-up digitising [to create new vector maps on-screen using a raster (remotely sensed image or aerial photograph) image as a background]; a complete GPS module to interface with GPS locators on vehicles in real-time; and a Routing module (including a shortest-path module).

There is also a GeoXplorer Professional Development Kit with a set of Run-time routines, which enable one to create one’s own GIS using C++ or VB.

In short, GeoConcept does indeed meet most of the criteria set earlier for a GIS for application in India. It is also relatively low in cost. The GeoXplorer Development Kit, for instance costs less than a single copy of PC-Arc-Info and provides, in addition to access to the 550-odd DLLs constituting the GIS engine, a copy of GeoConcept Standard as well as 5 run-time licenses. The GeoConcept Standard is in the same price range as Arc-View or MapInfo, while providing a world of better capability.

Conclusion:
We have discussed the problems associated with micro-watershed planning; we have identified the need for an integrated view of the spatial and non-spatial data in a watershed; we have suggested that a GIS is the (only) way this can be achieved. And we have identified several GIS, which can perform this function, and one in particular, which does it very well, cheaply and reliably.

References:

  • Monitoring and Evaluation of Watersheds in Karnataka using Satellite Remote Sensing Regional Remote Sensing Service Cenre, ISRO, Bangalore and State Watershed Development Programme, Govt. of Karnataka, Bangalore. Jan 1998
  • Menris Case Study Series No 5. GIS Applications to Natural Resource Management and Development Planning in a Rural Area, ICIMOD, July 1997
  • Handling Geographic Information Report of the Chorley Committee of Enquiry. Dept of the Environment, Govt. of U.K. London 1987
  • Manual of Soil and Water Conservation Practices Gurmel Singh, C Venkataramanan, G Sastry, B P Joshi Oxford & IBH Publg Co. Pvt Ltd 1996
  • GIS Assisted Watershed Management in Studies in Regional Planning. Thapa G B, Weber K E, Aung Z, HSD Res paper 29 AIT Bangkok 1992
  • Linking the Natural and Social Sciences. The LandUse / Land Cover change Core Project of the IGBP. Turner BL, IGBP Newsletter No 22 1995
  • Are Geographical Information Systems an appropriate technology for development in poor countries? A lesson from India. Dasharath Singh. Term Paper Dept of Geography, Univ of Durham, U.K. March 1996
  • Internet and Geoinfo System “Inter-GIS” Sri Krishna Sharma Osmania Univ, Hyderabad. GIS India April 1999
  • Methodology of Planning at the Gram Panchayat Level – applications of GIS A Baruah, N Ghosh, J G Krishnayya, NIRD Workshop February 1999
  • Design and Development of Software for Planning and Management of different types of Watersheds for Rural Areas – DoE Progress Report May 98 – PROGRESS, Hyderabad