Assessment of Land Use Change Impact on Ecohydrological Parameters Using Remote Sensing in the Sub-Catchments of the Patish Watershed, Israel
Total Page:16
File Type:pdf, Size:1020Kb
Assessment of Land Use Change Impact on Ecohydrological Parameters Using Remote Sensing in the Sub-Catchments of the Patish Watershed, Israel MSc Thesis by Bart de Jong August 2012 i | P a g e Assessment of Land Use Change Impact on Ecohydrological Parameters Using Remote Sensing in the Sub-Catchments of the Patish Watershed, Israel Master thesis Land Degradation and Development Group submitted in partial fulfillment of the degree of Master of Science in International Land and Water Management at Wageningen University, the Netherlands Study program: MSc International Land and Water Management (MIL) Student registration number: 860205-401-120 LDD 80336 Supervisors: Dr. Eli Argaman1 Dr. Saskia Keesstra2 Dr. Naftali Goldshleger1 Examinator: Dr. ir. M.J.P.M. Riksen, Dr. S.D. Keesstra Date: August 2012 1 Soil Erosion Research Station, Ministry of Agriculture, Israel 2 Wageningen University, Land Degradation and Development Group ii | P a g e Abstract De Jong, B. 2012. Assessment of Land Use Change Impact on Ecohydrological Parameters Using Remote Sensing in the Sub-Catchments of the Patish Watershed, Israel. MSc. Thesis. Land Degradation and Development Group, Wageningen University. Discharge measurements in the Patish watershed in the Northern Negev region in Israel show a low stream flow, which cannot be explained by hydrological modelling. One hypothesis is that low discharge is caused by changes in land use in the watershed, which influence the rainfall/runoff ratio. This hypothesis was tested by assessing the impact of land use change on Ecohydrological parameters. Change in land use is determined by analysing Landsat images using Definiens®. Soil Ecohydrological properties were derived by field experiments, and taking samples to be analysed in the laboratory. Rainfall records were collected, and investigated for possible trends. Land use was analysed using three classes: natural, agricultural and urban. The class of natural open area decreased from almost 70% of the area to just more than 50%. Agricultural area increased from almost 30% to almost 40%, and the urban class increased from 5% to 10% of the area. In some natural areas forest with terraces and limans is established, but these developments could not be distinguished in the Remote Sensing analysis. Saturated hydraulic conductivity was found higher for the agricultural area. Rainfall shows a high variability, both temporal and spatial. Trend lines derived were horizontal or slightly decreasing, though uncertainty is high. The hypothesis could not be confirmed. Developments in the Patish watershed could decrease runoff, especially the increase in agricultural and afforested area. But with current data available they do not explain for the low amounts of runoff observed. Therefore more quantitative research is recommended. Land cover change / Semi-arid area / Israel / Remote Sensing / Ecohydrological parameters iii | P a g e Acknowledgements Much gratitude is owed to the Soil Erosion Research Station (SERS) in Midreshet Ruppin, Israel. Thanks for their support in means of time, equipment, transport, knowledge and in various other practical issues. But also many thanks for their company, their willingness to help me, and all the nice lunches I could join (not to forget the barbeque). And for showing me the beautiful country of Israel. Especially I want to thank my supervisors in Israel; Dr. Eli Argaman and Dr. Naftali Goldshlager. Thanks to Eli for his advices, for stimulating me, and for all the knowledge he shared with me. Thanks for reviewing my thesis, and for giving me feedback on the various versions. And also for all his practical support and his friendship. Thanks to Naftali for involving me in his project, for all the time he spent with me, and for all other types of support. Thanks to all the technicians, to the ladies in the office, to the other scientists, and all the other people who have been so kind to me. Especially thanks to Roee BB, who was like a friend to me. Thanks to my supervisor in Wageningen; Dr. Saskia Keesstra. Thanks for your help, your input, and sorry for my lack of communication. And thanks to Dr. Michel Riksen, who helped and encouraged me in the last part of my research. Also thanks for the valuable feedback given on the draft of my thesis. And I would like to thank Pieter Slim, who continued to be interested in my research, and made much effort to help me finishing my work. I owe gratitude to the various persons who provided me with the meteorological data for the rainfall analysis; the Ben Gurion University and Gilat Research Farm who provided data on their website, and especially to Marc Perel from the Israel Meteorological Service, who provided data from their database. Thanks to family and friends, who supported me during the period of my research. And finally: thanks for all the patience of all the people I’ve let waiting for so long. iv | P a g e Contents Abstract ..................................................................................................................................... iii Acknowledgements ................................................................................................................... iv 1. Introduction ...................................................................................................................... 1 1.1 Background ............................................................................................................................. 1 1.2 Research framework ............................................................................................................... 2 1.2.1 Problem statement ........................................................................................................ 2 1.2.2 Research Goal ................................................................................................................. 2 1.2.3 Objectives ....................................................................................................................... 2 1.2.4 Research question .......................................................................................................... 3 2. Theoretical background .................................................................................................... 4 2.1 Land Cover Change ................................................................................................................. 4 2.2 Remote Sensing ...................................................................................................................... 5 2.3 Field water cycle ..................................................................................................................... 6 2.4 Ecohydrology........................................................................................................................... 6 2.5 Influence of Vegetation........................................................................................................... 7 2.6 Afforestation ........................................................................................................................... 8 2.7 Modelling the Effects of Land Use Change ............................................................................. 9 2.8 Ephemeral Streams ............................................................................................................... 10 2.9 Sampling of Natural Resources ............................................................................................. 11 2.10 Analysis of literature review ................................................................................................. 11 3. Methodology .................................................................................................................. 12 3.1 Research Area ....................................................................................................................... 12 3.1.1 Geography .................................................................................................................... 12 3.1.2 Soil ................................................................................................................................ 13 3.1.3 Land use ....................................................................................................................... 13 3.1.4 Climate ......................................................................................................................... 14 3.1.5 Vegetation .................................................................................................................... 14 3.2 Workflow .............................................................................................................................. 14 3.3 Remote Sensing Analysis....................................................................................................... 16 3.4 Field Work ............................................................................................................................. 18 3.4.1 Dry bulk density ............................................................................................................ 20 3.4.2 Saturated hydraulic conductivity ................................................................................. 20 3.4.3 Biomass ........................................................................................................................ 21 3.4.4 Analysis of soil samples ................................................................................................ 21 3.5