Lake Catchment Interaction Analysis by Using Remote Sensing and GIS Techniques – the case study of Kolleru Lake, South India

Wetlands belong to the most productive ecosystem on Earth. They provide many essential services to humans. They play an important role and possess ecosystem services, for example, in biodiversity conservation, for the hydrologic cycle, to buffer regional climate change, and for human health. Among the different types of wetlands, lakes (lacustrine wetlands) play a crucial role in maintaining global and regional water balances, natural and socio-economic resources, and habitats. Over the last decades, the lakes have gone through enormous changes derived from both natural processes and anthropogenic activities. Particularly, freshwater lakes are endangered through point and non-point pollutions, and such impacts are coming from agricultural runoff and industrial pollution, domestic waste, through municipal sewage, which may deteriorate the water quality and their ecological integrity. The Kolleru Lake wetland ecosystem in South India has been taken here as a case study, based on a comprehensive data analysis and modeling of Spatio-temporal variability of the pollutant loads, to achieve a better understanding of the man-environmental problems of the lake and its surrounding catchment. This is a necessary requirement for both better management of the agricultural, industrial, and water resources in the whole area and better lake protection and conservation. Kolleru Lake is the largest freshwater lake in India. It is a huge natural flood balancing reservoir and also a wildlife sanctuary. In 2002, the Ramsar Convention recognized the lake as a wetland of international importance. The lake is predominately fed by rivers. Among them, Budameru and Tammileru rivers are contributing to the lake influx substantially, plus supported by 68 minor irrigation (drainage) canals. The Kolleru Lake covers a total area of more than 90,100 hectares and holding approximately 1,350 cubic miles of freshwater. Additionally, Kolleru Lake provides drinking water to the inhabitants of the surrounded villages. The lake area up to 3' ft contour is consistent with water, while the 5' ft contour level of the Kolleru Lake belongs to the wildlife sanctuary. Further, it is mostly occupied by aquacultures followed by paddy cultivation, weed infests, and marshy land. There are many small scales to large scale industries growing steadily in order to support successful aquaculture. Before the 1970s, the lake area up to 5' ft contour was not occupied by any type of economic activity; however, the lake is saturated with water during the rainy season, and it remains dry during summer. Furthermore, it was completely free from contamination by aquaculture and agricultural activities before the 1970s. After the 1970s, the State Government had distributed the Kolleru Lake up to 5'ft contour area the poor people, migrant workers, and local inhabitants in the promise of whenever the government again needs the lake area, and they can take it back by paying compensation to them. Then farmers have started paddy cultivation in and around the lake. All bed villages in the lake region are frequently severely affected by massive flooding in connection with the submersion of paddy fields. Despite the fact that the state Government had encouraged the farmers to convert the paddy fields into fishponds by providing loans in order to overcome the floods. However, the maximum of lake area up to wildlife sanctuary is practiced by the aquaculture in the 1990s. Since 1970 until the current situation, the lake has been facing some severe environmental threats, such as degraded water quality, deteriorated aqua species and birds, and habitat losses, induced by human activities and accelerated by climate change. A major cause of the environmental problems was identified within the lake by the construction of fishponds resulted in pollution by using pesticides and waste food (exposed to bacterial diseases and infection) to enrich the fish growth. As a result, it causes biological magnification diseases, fertility, and respiratory problems to the animals, birds, and humans who live near to the lake. Thereby the ecosystem will become an inhospitable environment for those aqua species and birds. The fish ponds occupied approximately 42% of the lake area while aquaculture had encroached another 8.5%, together covering 50% of the lake region. If the human-induced debasement of the lake will continue, the lake will no longer cease to exist, and the wildlife species soon will disappear. Apart from the aquaculture tradition, the Kolleru Lake catchment is known for its intensive paddy cultivation. However, the massive application of pesticides and chemical fertilizers to agricultural lands across the catchment area is one reason for the eutrophication in Kolleru Lake. In addition to the several factors that influence the lake ecosystem, industrial pollution causes deteriorating water quality and makes them unfit for drinking water for the inhabitants of the villages around the Kolleru Lake. Both point and non-point sources issued threatens to the lake area becomes more sensitive by anthropogenic activities. The main focus of the present research was to analyze the problems related to the lake catchment and give recommendations to the government about the insight view of the land use cover and enlighten the public perception towards the lake degradation. However, sedimentation in a lake is a natural consequence of the inflow of respected tributaries, rivers, and streams. In addition to the natural influence, man-made activities like land use and others are also responsible for erosion in the catchment and the sediment transport and accumulation of the sediments in both the lower sections of the catchment and the lake basin itself, as discussed in the first research objective. Extensive use of land and the indiscriminate rise of embankments for the construction of fishponds as well as agricultural functions has resulted in widespread soil erosion in the catchment and sedimentation over the deltaic part of the Kolleru Lake catchment. In addition, the perennial rivers of Krishna and Godavari drift down to the lake about 68,000 tons/yr of sediments that coming from the whole catchments after passage from the river banks and river beds. The objective of this part was to analyze both the average annual soil loss rate and its change from the catchment and the sediment yields by using the RUSLE model both for the terrestrial part and the semi-aquatic deltaic part of the Kolleru Lake catchment for the years 1972 and 2012. The results indicated that the average annual soil loss was estimated with 13.6 t/ha/yr, classifying the Kolleru Lake Basin under a very high erosion rate category. Whereas, the average annual sediment yield was determined with 7.61 t/ha/yr. The resultant difference of the sediment balance is temporally interbedded within the terrestrial sites and within the river banks and river beds. However, this study has found that tributaries and streamlines of the catchment carry high sediment loads to the lake. This research has proved how intensive agricultural activities in wetland catchments interact with the pollution levels of the lake, causing a deteriorated water quality. Agricultural runoff (runoff from catchment areas dominated by agricultural use) is the main driving factor of accumulated non-point source pollution of the lake water, with side-effects on sediments and silts near the downstream areas of the Kolleru Lake catchment. It primarily caused eutrophication in the lake subsequently that led to proliferating the weeds. However, the second objective of the research was to estimate the tributaries' sub-basin loads and to highlight the diffuse critical sources against the village communities. For this purpose, the Soil and Water Assessment Tool (SWAT) was used to model the diffuse sources in the catchment. The spatial distribution of nitrate-nitrogen (NO3-N) and total phosphorus (TP) emissions were quantified. Some sub-basins contribute more pollutant load to the lake. Alternately, the first and second BMPs (Best Management Practices) level priority areas were identified. Further, suggestions for the implementation of agricultural management practices have been provided for the crucial protection of the lake ecosystem. Consequently, the Kolleru Lake wetland ecosystem is known for its both abundant water availability as well as water scarcity. The river and streams water diverted into the agricultural lands, and still, there is a dire need for groundwater too. When the monsoon rain was weak, and after rainless summer periods, the lake falls more or less dry. Therefore there is a high demand for groundwater, which is continuously increasing. An effective way to analyze groundwater recharge and groundwater availability is a remote sensing and GIS based mapping. The theoretical concepts are involved in this objective is more useful for t further research of the link between surface emission and groundwater contamination. That is why the present research has been investigated as the third objective, the potential groundwater resources in the catchment. A simple mathematical equation was derived from the catchment hydrologic characteristics. The catchment characteristics were analyzed and based on the previous literature sources, and the thematic weight was assigned to evaluate potential groundwater zones. About 13% of the catchment area falls under poor conditions, 38% of the area falls under moderate conditions, 42% of the area falls under good conditions, and about 7% of the area is under excellent condition. These results are a contribution to future groundwater management projects and artificial recharge plans of the Kolleru Lake catchment to maintain sufficient groundwater levels. Due to the still existing lack of observed data of the tributaries, i.e., runoff, sediment, water quality parameters, nutrient load, the used methods are limited and suitable just for an estimation. Sufficient calibration and validation of the results were also limited because the access to the study area and to an onside research institute was not allowed for the Ph.D. candidate, because of its status as a Ph.D. student from Germany. Field investigations on the interaction of pollutant loads with the runoff would be advantageous for a better calculation of the pollutant load and its dynamic. Because of the limited funding capacity, it is challenging to do a field survey to control every remote sensing and GIS result of this research. That is why, without a few exceptions, this study was conducted dominantly based on remote sensing data and accessible weather and soil data. From the research results emphasized that the Kolleru Lake water level and water quality are highly degraded, respectively polluted with metals, agricultural contaminants, which makes the lake water not advisable for human consumption. The erosion and sedimentation loads are also high, and the priority management practices should be targeted already in the middle catchment region. These results give a general understanding of the pollutant levels in the lake, which should be useful for government management plans.

Simulating the impact of Grain-for-Green Programme on ecosystem services trade-offs in Northwestern Yunnan, China

Prefecture in 2000, land use/cover has undergone dramatic changes. This study used the CLUE-S model to simulate land use change in 2030, and explored the spatial pattern and relationship of different ecosystem services under the four scenarios of GFGP. The results show that, GFGP can help to improve indirect services of ecosystems, such as carbon storage and soil conservation. However, direct services of the ecosystem will decline, such as food production and water yield. Compared with 2010, the overall supply level of the four ecosystem services is the most balanced in the moderate GFGP scenario. In this scenario, total food production decreased by 179,000 tons and water yield decreased by 57 million cubic meters. Carbon storage and soil conservation continued to grow, increasing by 21.86 million tons and 17.87 million tons, respectively. The changes of ecosystem services in the strong GFGP scenario are extreme. The increases in carbon storage and soil conservation are at the expense of a significant reduction in food production and water yield. It can be concluded that GFGP may lead to intensifying ecosystem services trade-offs. Through comparing the changes of ecosystem services under different GFGP scenarios, it is found that the implementation intensity of GFGP should be deeply concerned in policy making

Watershed Water Environment and Hydrology under the Influence of Anthropogenic and Natural Processes

The major aims of this book, “Watershed Water Environment and Hydrology under the Influence of Anthropogenic and Natural Processes”, are to focus on innovative/new ideas on the watershed water environment from different perspectives across the field; distinguish the evolution of watershed water ecological and environmental quality; clarify the biogeochemical cycling of elements or pollutants; identify and quantify the sources of pollutants; and assess the ecological risk and human health risk of pollutants in the water environment at different watershed scales. In particular, eight peer-reviewed articles were collected, mainly reporting the hydrochemistry-based watershed weathering processes and their environmental implications, trace elements and their risks, and the nutrients cycle in river–reservoir systems. Overall, these papers contribute to several aspects of the watershed water environment and are valuable for river water resource protection and management

Development of An Integrated GIS-Based System for Surface Water Quality Assessment and Management (GIS-SWQAM)

It is an fact that surface water receives a large volume of pollutants from industrial, agricultural, and municipal sources. The adverse health and environmental effects of surface water pollution have been a major concern in environmental management. Water quality models are useful tools to simulate the complex transport and fate of pollutants in a water body and predict the short-term and long-term effects on water quality variation. The emergence of spatial information technologies, such as Geographic Information System (GIS) make it possible to assess and predict surface water quality with more details with respect to spatial information. The focuses of this thesis is to develop a comprehensive system named as GIS-SWQAM, which includes: (1) the development of a GIS-based water quality assessment system to assess the water quality and provide spatial distribution of water quality variables; (2) the development of an artificial neural network model to predict the change of water quality variables; (3) the development of a user interface that integrates the above models and functions; furthermore, a comparative analysis of the modeling approach developed in the GIS-SWQAM and the commercial model MIKE 21 was performed through field case studies. The GIS-based water quality and ecological risk assessment models (MWQ module for marine water quality assessment and LWQ module for lake water quality assessment) are developed by integrating a fuzzy risk assessment model, a eutrophication risk assessment model, a heavy metal risk assessment model, a dynamic database, the ArcGIS Engine, and a graphical user interface (GUI). The assessment results are both spatially and visually presented in the form of contour maps and color-coded maps that indicate risk levels. A large amount of data with both spatial and temporal distributions is managed by the developed system and analyzed by the assessment modules. The developed MWQ and LWQ modules are respectively applied in the Liaodong Bay of China and Lake Champlain. The MWQ and LWQ produce risk maps that depict the spatial distribution of integrated water quality index values, eutrophication risk levels and heavy metal risk levels in the study area. The maps generated can provide a better understanding of the distribution of the water quality and ecological risk levels. The primary factors that affect the water quality are subsequently examined using the visualized results. An artificial neural network model with the back-propagation algorithm (BPANN) is first developed using Matlab to predict the chlorophyll-a concentration in Lake Champlain. Then, the algorithm of the BPANN model is built using the C# programing language and integrated with GIS and the database to build the ANN module, which is applied to predict the total phosphorus concentration in Lake Champlain. The best performing model is determined among the results of models built with different combination of input variables, which are preliminarily selected by linear correlation analysis and domain knowledge. Subsequently, the performances of the BPANN models are validated by a new set of field data. Similar to the MWQ and LWQ modules, the ANN module also produces the spatial distribution maps of the predicted concentrations; errors made during the prediction are presented in the user interface. The results indicate that the developed BPANN models can provide acceptable prediction results and can be used to provide a quick modeling assessment of water quality variation for managers. In this thesis, the MIKE 21 FM software is also used to establish a hydrodynamic model coupled with a transport model to simulate the total phosphorus concentration in Lake Champlain. A comparative analysis is performed between the results of the MIKE 21 model and the BPANN model. The results of the MIKE 21 model are acceptable, but not as good as that of the BPANN model. This further verifies that the developed BPANN model is a reliable tool to assess the lake eutrophication and to help managing lake water quality. The developed system can be also applied to surface water management in other area

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Includes bibliographical references.A In order to promote irrigation sustainability through reporting by irrigation water managers around Australia, we have developed an adaptive framework and methodology for improved triple-bottom-line reporting. The Irrigation Sustainability Assessment Framework (ISAF) was developed to provide a comprehensive framework for irrigation sustainability assessment and integrated triple-bottom-line reporting, and is structured to promote voluntary application of this framework across the irrigation industry, with monitoring, assessment and feedback into future planning, in a continual learning process. Used in this manner the framework serves not only as a "reporting tool", but also as a "planning tool" for introducing innovative technology and as a "processes implementation tool" for enhanced adoption of new scientific research findings across the irrigation industry. The ISAF was applied in case studies to selected rural irrigation sector organisations, with modifications to meet their specific interests and future planning

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Includes bibliographical references.The two-layer model of Shuttlerworth and Wallace (SW) was evaluated to estimate actual evapotranspiration (ETa) above a drip-irrigated Merlot vineyard, located in the Talca Valley, Region del Maule, Chile (35° 25' LS; 71° 32' LW ; 136m above the sea level). An automatic weather system was installed in the center of the vineyard to measure climatic variables (air temperature, relative humidity, and wind speed) and energy balance components (solar radiation, net radiation, latent heat flux, sensible heat flux, and soil heat flux) during November and December 2006. Values of ETa estimated by the SW model were tested with latent heat flux measurements obtained from an eddy-covariance system on a 30 minute time interval. Results indicated that SW model was able to predict ETa with a root mean square error (RMSE) of 0.44 mm d-1 and mean absolute error (MAE) of 0.36 mm d-1. Furthermore, SW model predicted latent heat flux with RMSE and MAE of 32 W m-2 and 19W m-1, respectively

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Salt management is a critical component of irrigated agriculture in arid regions. Successful crop production cannot be sustained without maintaining an acceptable level of salinity in the root zone. This requires drainage and a location to dispose drainage water, particularly, the salts it contains, which degrade the quality of receiving water bodies. Despite the need to generate drainage water to sustain productivity, many irrigation schemes have been designed and constructed with insufficient attention to drainage, to appropriate re-use or disposal of saline drainage water, and to salt disposal in general. To control the negative effects of drainage water disposal, state and federal agencies in several countries now are placing regulations on the discharge of saline drainage water into rivers. As a result, many farmers have implemented irrigation and crop management practices that reduce drainage volumes. Farmers and technical specialists also are examining water treatment schemes to remove salt or dispose of saline drainage water in evaporation basins or in underlying groundwater. We propose that the responsibility for salt management be combined with the irrigation rights of farmers. This approach will focus farmers' attention on salt management and motivate water delivery agencies and farmers to seek efficient methods for reducing the amount of salt needing disposal and to determine methods of disposing salt in ways that are environmentally acceptable

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Includes bibliographical references.Since 3000 BC, rice has been the main crop in the Korean Peninsula, and where currently most of the available irrigation water is used to grow paddy rice. Methods for calculating the quantity of irrigation water required developed in the 1990's were compared to quantities measured in the field. The largest difference between calculated and measured quantities occurred in April and May. Based on field data we obtained in the middle part of the Korean Peninsula, significant changes have occurred in rice management, which has changed the amount of irrigation water required. Rice is now transplanted earlier, and duration of the transplanting phase on the regional scale is shorter through mechanization and consolidation of land holdings. These changes need to be taken into account when calculating the quantity of water needed for irrigation

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Includes bibliographical references.Experiences establishing Water User Associations (WUAs) in Egypt have been carried out for the past 15 years, with increasingly promising results. Most of these activities have been pilot projects aiming to demonstrate the benefits and sustainability of WUAs. They were consequently implemented through a centralized and resource-intensive process and focused on limited numbers of associations. Since 2003, the Ministry of Water Resources and Irrigation (MWRI) has adopted as policy the large-scale development of Branch Canal WUAs. With support from USAID, about 600 branch canal WUAs (BCWUAs) have since been established, covering 15% of Egypt's irrigated area and involving half a million farmers and residents. In order to achieve this impressive outcome, a different approach has been developed and implemented, emphasizing the direct involvement of MWRI field staff and a partnership between water users and MWRI managers. This paper also argues that the conventional approach of forming WUAs by focusing on water users, and empowering them to take over the O&M responsibilities of irrigation systems, is not adapted to the Egyptian context