scholarly journals KARAKTERISTIK, KESESUAIAN, DAN PENGELOLAAN LAHAN TAMBAK DI KOTA PEKALONGAN PROVINSI JAWA TENGAH

2016 ◽  
Vol 5 (3) ◽  
pp. 505 ◽  
Author(s):  
Rachmansyah Rachmansyah ◽  
Akhmad Mustafa ◽  
Mudian Paena
Keyword(s):  
Land Management ◽  
Paddy Field ◽  
Coastal Area ◽  
Sea Water ◽  
Saline Water ◽  
C:N Ratio ◽  
Land Suitability ◽  
Geographical Information ◽  
Acid Sulfate Soil ◽  
Acid Sulfate

Kota Pekalongan memiliki lahan tambak yang produktivitas tambaknya masih tergolong relatif rendah. Oleh karena itu, dilakukan penelitian untuk mengetahui karakteristik lahan dalam upaya menentukan kesesuaian dan pengelolaan lahan untuk budidaya tambak demi peningkatan produktivitas tambak di Kota Pekalongan. Faktor yang dipertimbangkan dalam mengetahui karakteristik lahan adalah: tanah, topografi, hidrologi, vegetasi, dan iklim. Analisis spasial dalam Sistem Informasi Geografis digunakan dalam penentuan kesesuaian lahan untuk budidaya tambak. Pengelolaan lahan ditentukan berdasarkan karakteristik lahan yang disesuaikan dengan teknologi dan komoditas yang dapat diaplikasikan di tambak. Tanah tambak di Kota Pekalongan tergolong tanah aluvial non-sulfat masam yang tidak memiliki potensi kemasaman tanah yang tinggi dan sebagian kecil tanah sulfat masam. Sumber air laut untuk tambak tergolong agak keruh dan salinitas air tambak cukup bervariasi sebagai akibat adanya sumber air tawar yang berasal dari Sungai Pekalongan dan sodetan. Vegetasi bakau adalah jenis vegetasi yang dominan di kawasan tambak sebab adanya Program GERHAN (Gerakan Nasional Rehabilitasi Hutan dan Lahan) di Kota Pekalongan. Curah hujan di Kota Pekalongan sebesar 2.300 mm/tahun di mana curah hujan yang rendah dijumpai pada bulan Juli sampai Oktober. Di kawasan pesisir Kota Pekalongan dijumpai tambak, sawah, sawah terintrusi, dan pemukiman yang luasnya masing-masing 332,29; 372,53; 183,83; dan 619,73 ha. Dari luas tambak yang ada di Kota Pekalongan, yaitu 331,292 ha ternyata tidak ada tambak yang tergolong sangat sesuai (kelas S1), 191,856 ha tergolong cukup sesuai (kelas S2) dan 140,436 ha tergolong kurang sesuai (kelas S3). Pada areal yang mengandung unsur atau senyawa penyebab kemasaman yang tinggi disarankan untuk melakukan upaya perbaikan tanah terlebih dahulu berupa remediasi, pemberian pupuk yang mengandung nitrogen pada areal yang memiliki rasio C:N tanah yang tinggi serta pemberian pupuk kandang pada tanah yang mengandung liat lebih besar 60% dan bahan organik kurang dari 8%.Pekalongan City has brackishwater ponds with low productivity. Hence, a survey was conducted to know land characteristics as an effort to determine land suitability and land management to increase the productivity of brackishwater ponds in Pekalongan City, Central Java Province. Factors considered to determine the characteristics of land were soil, topography, hydrology, vegetation, and climate. Spatial analysis in Geographical Information System was used to determine land suitability for brackishwater ponds. Land management was determined based on the characteristics of land conditioned to the types of technology and commodity applied in the brackishwater ponds. Soil of brackishwater ponds in Pekalongan City was dominated by alluvial non-acid sulfate soil in large areas and acid sulfate soil in small areas. Source of sea water for brackishwater ponds has high turbidity and high variation of salinity due to presence of freshwater supply from Pekalongan River and man made canals. Mangrove vegetation is dominant in the coastal area of Pekalongan City, because the presence of GERHAN (National Action for Forest and Land Rehabilitation) Program. The average of rainfall in Pekalongan City is 2,230 mm/year, where low of rainfall occurrs in July until October. The result revealed that the coastal area of Pekalongan City had brackishwater ponds, paddy field, paddy field intruded saline water and settlement of 332.29 ha; 372.53 ha; 183.83ha; and 619.73 ha, respectively. From the total brackishwater ponds in Pekalongan City i.e. 331.292 ha, there were no brackishwater ponds classified as highly suitable (S1 class), but it was found moderately suitable or S2 class (191.856 ha) and marginally suitable or S3 class (140,436 ha). It is suggested to conduct improving soil quality first, including remediation of the areas that contain elements or compounds causing the high acidity of soil, fertilizing with fertilizer containing nitrogen in the areas that have high C:N ratio and applying manure in the soils that contain clay more than 60% and organic matter less than 8%. 

scholarly journals KARAKTERISTIK, KESESUAIAN, DAN PENGELOLAAN LAHAN UNTUK TAMBAK BUDIDAYA DI KABUPATEN LUWU UTARA PROVINSI SULAWESI SELATAN

2016 ◽  
Vol 5 (3) ◽  
pp. 449 ◽  
Author(s):  
Hasnawi Hasnawi ◽  
Akhmad Mustafa
Keyword(s):  
Land Management ◽  
Sandy Loam ◽  
Peat Soil ◽  
Land Suitability ◽  
Geographical Information ◽  
Acid Sulfate Soil ◽  
Acid Sulfate ◽  
Nypa Fruticans ◽  
Culture Production ◽  
High Level

Kabupaten Luwu Utara (Lutra) memiliki lahan potensial untuk tambak dan produktivitas tambaknya untuk budidaya udang dan ikan relatif rendah. Oleh karena itu, dilakukan survai untuk mengetahui karakteristik lahan dalam upaya menentukan kesesuaian dan pengelolaan lahan untuk budidaya tambak demi peningkatan produktivitas tambak di Kabupaten Lutra. Faktor yang dipertimbangkan dalam mengetahui karakteristik lahan adalah: tanah, topografi, hidrologi, vegetasi, dan iklim. Analisis spasial dalam Sistem Informasi Geografis digunakan untuk penentuan kesesuaian lahan budidaya tambak. Pengelolaan lahan ditentukan berdasarkan karakteristik lahan yang disesuaikan dengan teknologi dan komoditas yang dapat diaplikasikan di tambak. Kawasan pesisir Kabupaten Lutra didominasi oleh tanah bermasalah yaitu tanah sulfat masam, tanah gambut, dan tanah sulfat masam yang berasosiasi dengan tanah gambut. Tanah sulfat masam adalah jenis tanah dominan di Kabupaten Lutra yang memiliki potensi kemasaman dan unsur-unsur toksik yang tinggi dan sebaliknya unsur hara makro yang rendah dengan tekstur tanah yang  tergolong pasir berlempung dan lempung berpasir. Topografi lahan umumnya relatif datar dan elevasi yang tergolong rendah yang didominasi oleh vegetasi Sonneratia sp., Rhizophora sp., dan Nypa fruticans. Curah hujan yang rendah pada bulan September sampai Februari berdampak pada kondisi kualitas air yang lebih baik terutama pada salinitas, pH, Ca, dan Mg yang lebih tinggi daripada musim hujan. Hasil analisis menunjukkan bahwa lahan tambak di Kabupaten Lutra yang tergolong sangat sesuai (kelas S1) seluas 1.821,9 ha; tergolong cukup sesuai (kelas S2) seluas 368,2 ha; dan tergolong sesuai marjinal (kelas S3) seluas 3.268,1 ha. Untuk perbaikan tanah bermasalah tersebut dapat dilakukan melalui remediasi maupun dengan pemupukan.Coastal area of North Luwu Regency has suitable areas for brackishwater ponds, however many of those areas are low in productivity for shrimp and fish culture. Hence, a survey was conducted to study the characteristics of the area as an effort to determine land suitability and land management for increasing the productivity of brackishwater ponds in North Luwu Regency. Factors that were taken into acount to determine the characteristics of land were soil, topography, hydrology, vegetation and climate condition. Spatial analysis using Geographical Information System software was used to determine land suitability for brackishwater ponds. Land management was determined based on the characteristics of land that are adaptable to the types of technology and commodity applied in the brackishwater ponds. The coastal area of North Luwu Regency was dominated by types of infertile soils, i.e., acid sulfate soil, peat soil and acid sulfate soil associated with peat soil, Acid sulfate soil in North Luwu Regency has high potential acidity and high level toxic element. On the other hand, the area has low level macro elements and soil textures are dominated by loamy sand and sandy loam. In general, the land topography is flat and the elevation is classified as low. The areas are dominated by Sonneratia sp., Rhizophora sp., and Nypa fruticans. Low rainfall level is occurred in September to February and directly affects the coastal water quality, causing higher salinity, pH, Ca, and Mg than in rainy season. Results of analysis show that brackishwater ponds in North Luwu Regency were classified as highly suitable (1,821.9 ha), moderately suitable (368.2 ha) and marginally suitable (3,268.1 ha). Remediation and fertilization are highly recommended in order to improve the soil quality for optimum culture production.

Available carbon and nitrate increase greenhouse gas emissions from soils affected by salinity

Soil Research ◽  
2017 ◽  
Vol 55 (1) ◽  
pp. 47 ◽  
Author(s):  
Duy Minh Dang ◽  
Ben Macdonald ◽  
Sören Warneke ◽  
Ian White
Keyword(s):  
Carbon Cycling ◽  
Soil Nitrogen ◽  
Saline Water ◽  
Alluvial Soil ◽  
Acid Sulfate Soil ◽  
N2o Production ◽  
Saline Water Intrusion ◽  
Acid Sulfate ◽  
Water Intrusion ◽  
Available Carbon

Sea-level rise and saline water intrusion have caused a shortage of fresh water and affected agricultural areas globally. Besides inundation, the salinity could alter soil nitrogen and carbon cycling in coastal soils. To examine the effect of salinity, an incubation experiment was used to investigate soil nitrogen and carbon cycling from an acid sulfate soil and an alluvial soil with and without additional nitrogen and carbon sources. Four levels of saline solution of 0.03, 10, 16 and 21dSm–1 were used to submerge acid sulfate and alluvial soil samples in a 125-mL jar. The experimental jars were incubated in the dark at 25°C. Gas samples were collected over 4 weeks and analysed for nitrous oxide (N2O), carbon dioxide (CO2) and methane (CH4). The results showed that salinity significantly decreased N2O emissions from the acid sulfate soil but did not affect emissions from the alluvial soil. Addition of glucose and nitrate enhanced N2O production in both salt-affected soils. Emissions of CO2 were not different among the salinity treatments, whereas available carbon and nitrate promoted soil respiration. Changes in CH4 fluxes over the 4-week incubation were the same for both soils, and substrate addition did not affect emissions in either soil. The findings indicate that salinity has altered carbon and nitrogen cycles in the acid sulfate soil, and future fertiliser and crop management will need to account for the changed nutrient cycling caused by saline water intrusion and climate change.

scholarly journals SPATIAL DISTRIBUTION OF SOME CHEMICAL CHARACTERISTICS OF AN ACID SULFATE SOIL-AFFECTED BRACKISHWATER PONDS IN THE COASTAL AREA OF LUWU REGENCY SOUTH SULAWESI PROVINCE

2014 ◽  
Vol 9 (1) ◽  
pp. 73
Author(s):  
Erna Ratnawati ◽  
Akhmad Mustafa
Keyword(s):  
Spatial Distribution ◽  
Coastal Area ◽  
Soil Nutrient ◽  
Simple Random Sampling ◽  
Soil Characteristics ◽  
Chemical Characteristics ◽  
Acid Sulfate Soil ◽  
Acid Sulfate ◽  
South Sulawesi ◽  
Brackishwater Pond

Spatial distribution of brackishwater pond soil has important role in the system of bioenvironment including brackishwater pond environment. This research was aimed to determine the spatial distribution of some chemical characteristics of an acid sulfate soil-affected brackishwater pond in coastal area of Luwu Regency South Sulawesi Province, Indonesia. ALOS AVNIR-2 images (acquisition 16 May 2008, 16 October 2008, 17 September 2009) were integrated with Indonesian Topographic maps to obtain base map. Sampling soil points were determined by simple random sampling in 104 points for two different soil depths i.e. 0-0.2 m and 0.5-0.7 m. A total of 18 soil chemical characteristics was measured in the field and analyzed in the laboratory. Geostatistic using kriging method in the ArcGIS 9.3 software was used to interpolate the data. The results of this study indicated that in general pond soil chemical characteristics in Luwu Regency could be categorized with high variability or relatively heterogenic wi th the value of var iation coefficient more than 36%. The soil characteristics that explain acidity had shown similar pattern in spatial distribution as well as other soil characteristics with soil nutrient. The high value of pH and low value of PO4 were generally found in the northern part of Luwu Regency, including East Lamasi, East Walenrang, Bua, and Ponrang Subdistricts. It is recommended that soil management in brackishwater ponds of Luwu Regency could be based on soil chemical characteristics so its could improve the production through minimizing the input, increasing carrying capacity, and avoiding environmental degradation.

scholarly journals Water Pollution Index (WPI) and Incidence of Diarrhea Among Children Under Five Years Old in Coastal Area of Semarang City, Indonesia

2020 ◽  
Vol 202 ◽  
pp. 05022
Author(s):  
Fatimatuzzahro ◽  
Mursid Raharjo ◽  
Nurjazuli
Keyword(s):  
Water Pollution ◽  
Coastal Area ◽  
Sea Water ◽  
Pollution Index ◽  
Geographical Information ◽  
Bivariate Analysis ◽  
Cross Sectional ◽  
Children Under Five ◽  
Water Pollution Index ◽  
Under Five

Coastal area of Semarang City is susceptible to water pollution and one of which is due to sea water intrusion. Diarrhea is an infectious disease that causes more than 26,93% of mortality in children under five years old and cases average over 30% in coastal area of Semarang City. The aim of this study was to evaluate assotiation between Water Pollution Index (WPI) and incidence of diarrhea in children under five years old. This type of research is an observational analytic study with a cross sectional study design. Sampel consisted of 18 respondens from 7 districts in coastal area of Semarang City. Independent variable is water pollution index which is calculated based on parameters of pH, salinity, TDS, and E.coli. Dependent variable is incidence of diarrhea under five years old. Data analysis used univariate and bivariate analysis using rank spearman correlation and Geographical Information System (GIS). Result found moderate category of water pollution index in Mangkang Kulon, Mangunharjo, Mangkang Wetan, and Bandarharjo. We identified associations between water pollution index (p 0,014, r: 0,857), E.coli in water (p 0,017, r: 0,842), salinity in water (p 0,013, r: 0,860), TDS in water (p 0,011, r: 0,871) and incidence of diarrhea. There is no relationship significantly between pH in water (p 0,782, r: -0,130) and incidence of diarrhea. WPI provides information on water quality and contaminants in water has potential trigger to digestive disorders. Cases of diarrhea occured by pathogenic microbiological, material, and chemical compounds. Conclussion, there is assotiation between water pollution index and incidence of diarrhea in coastal area of Semarang City.

scholarly journals Analisis Kesesuaian Lahan Wilayah Pesisir Kota Bengkulu melalui Perancangan Model Spasial dan Sistem Informasi Geografis (SIG)

2009 ◽  
Vol 23 (2) ◽  
pp. 101 ◽  
Author(s):  
Yulian Fauzi ◽  
Boko Susilo ◽  
Zulfia Memi Mayasari
Keyword(s):  
Brackish Water ◽  
Coastal Area ◽  
Land Suitability ◽  
Geographical Information ◽  
Fish Ponds ◽  
Suitability Analysis ◽  
Conservation Area ◽  
Land Suitability Analysis ◽  
Water Fish ◽  
Brackish Water Fish

This research is aimed to alocate land management and use coastal and ocean area Sub-Province base on digital through Geographical Information System (GIS). This research was done in the coastal area Kota Bengkulu, through spatial alocate analysis and land suitability analysis for brackish water fish ponds, maritime tourism and conservation areas. Approach used in this research is spatial analysis to parameter/variable and land suitability criteria consist of element abiotik, biotik, culture, and spatial use (RTRW). Land suitability analysis is done by using SIG through overlay technique. Result of research indicate that from 7 sub district of coastal area of exist in Kota Bengkulu, land suitability (S1) for brackish water fish ponds are found in sub-district Muara Bangkahulu and Kampung Melayu. Land suitability (S1) for the maritime tourism are found in sub-district Teluk Segara and Ratu Samban, while Land suitability (S1) for conservation area of are found in sub-district Kampung Melayu.

scholarly journals KELAYAKAN LAHAN PERTAMBAKAN DI TANAH SULFAT MASAM, KABUPATEN LUWU TIMUR, SULAWESI SELATAN

2006 ◽  
Vol 1 (2) ◽  
pp. 281
Author(s):  
Brata Pantjara ◽  
Aliman Aliman ◽  
Abdul Mansyur ◽  
Utojo Utojo
Keyword(s):  
Brackish Water ◽  
Secondary Data ◽  
Land Suitability ◽  
Primary Data ◽  
Acid Sulfate Soil ◽  
Acid Sulfate ◽  
South Sulawesi ◽  
Water Pond ◽  
Brackish Water Aquaculture ◽  
Brackish Water Pond

Salah satu lahan yang bisa dikembangkan untuk budi daya tambak adalah tanah sulfat masam. Di Indonesia potensinya cukup luas dan umumnya lahan semacam ini berada di kawasan pesisir. Penelitian ini bertujuan untuk mengetahui potensi kelayakan lahan tanah sulfat masam untuk pertambakan dan optimalisasi pemanfaatannya berdasarkan tingkat kesesuaian lahan dan daya dukung lingkungan. Penelitian dilakukan di Kabupaten Luwu Timur, Sulawesi Selatan. Metode penelitian dengan melakukan survai untuk mendapatkan data primer. Sedangkan data sekunder diperoleh dari instansi terkait dan peta yang diperlukan untuk proses analisis dengan Sistem Informasi Geografis (SIG). Analisis data melalui tumpang susun dari beberapa peta dan data primer pada setiap pengamatan dengan mempertimbangkan pembobotan dan skala penilaian untuk mendapatkan nilai skoring dalam menentukan kesesuaian lahan budi daya tambak. Hasil analisis kelayakan lahan untuk tambak didapatkan nilai potensi dan kelayakan seluas 5.617,9 ha yang terdiri atas 709,4 ha kelayakan tinggi; 3.947,7 ha kelayakan sedang; dan 960,7 ha kelayakan rendah.One of land that can be developed for brackish water aquaculture is acid sulfate soil. The potency of acid sulfate soil in Indonesia is relatively large and generally found in coastal area. The objectives of this research to know the potency and land suitability of acid sulfate soil for brackish water aquaculture and optimal utilization based on land suitability level and its carrying capacity. This research was conducted at Malili Sub District; East Luwu Regency, South Sulawesi. Surveys have been done collected primary data. while secondary data was obtained from related Institution and needed maps for Geographic Information System (GIS) analysis, with overlying maps and primary data in each station observation with considering and assessment scale value of determining land suitability for brackish water pond. The result of maps analysis had been obtained the potency and land suitability at Malili Sub district were 5,617.9 ha consisted of 709.4 ha (high suitability); 3,947.7 ha (moderate suitability); and 960.7 ha (low suitability).

PEUBAH KUALITAS AIR YANG MEMPENGARUHI PERTUMBUHAN RUMPUT LAUT (Gracilaria verrucosa) DI TAMBAK TANAH SULFAT MASAM KECAMATAN ANGKONA KABUPATEN LUWU TIMUR PROVINSI SULAWESI SELATAN

2009 ◽  
Vol 4 (1) ◽  
pp. 125
Author(s):  
Akhmad Mustafa ◽  
Rachmansyah Rachmansyah ◽  
Dody Dharmawan Trijuno ◽  
Ruslaini Ruslaini
Keyword(s):  
Water Quality ◽  
Growth Rate ◽  
Ammonium Phosphate ◽  
Gracilaria Verrucosa ◽  
Acid Sulfate Soils ◽  
Acid Sulfate Soil ◽  
Acid Sulfate ◽  
Independent Variables ◽  
Water Quality Variables ◽  
Sulfate Soils

Rumput laut (Gracilaria verrucosa) telah dibudidayakan di tambak tanah sulfat masam dengan kualitas dan kuantitas produksi yang relatif tinggi. Oleh karena itu, dilakukan penelitian yang bertujuan untuk mengetahui peubah kualitas air yang mempengaruhi laju pertumbuhan rumput laut di tambak tanah sulfat masam Kecamatan Angkona Kabupaten Luwu Timur Provinsi Sulawesi Selatan. Pemeliharaan rumput laut dilakukan di 30 petak tambak  terpilih selama 6 minggu. Bibit rumput laut dengan bobot 100 g basah ditebar dalam hapa berukuran 1,0 m x 1,0 m x 1,2 m. Peubah tidak bebas yang diamati adalah laju pertumbuhan relatif, sedangkan peubah bebas adalah peubah kualitas air yang meliputi: intensitas cahaya, salinitas, suhu, pH, karbondioksida, nitrat, amonium, fosfat, dan besi. Analisis regresi berganda digunakan untuk menentukan peubah bebas yang dapat digunakan untuk memprediksi peubah tidak bebas. Hasil penelitian menunjukkan bahwa laju pertumbuhan relatif rumput laut di tambak tanah sulfat masam berkisar antara 1,52% dan 3,63%/hari dengan rata-rata 2,88% ± 0,56%/hari. Di antara 9 peubah kualitas air yang diamati ternyata hanya 5 peubah kualitas air yaitu: nitrat, salinitas, amonium, besi, dan fosfat yang mempengaruhi pertumbuhan rumput laut secara nyata. Untuk meningkatkan pertumbuhan rumput laut di tambak tanah sulfat masam Kecamatan Angkona Kabupaten Luwu Timur dapat dilakukan dengan pemberian pupuk yang mengandung nitrogen untuk meningkatkan kandungan amonium dan nitrat serta pemberian pupuk yang mengandung fosfor untuk meningkatkan kandungan fosfat sampai pada nilai tertentu, melakukan remediasi untuk menurunkan kandungan besi serta memelihara rumput laut pada salinitas air yang lebih tinggi, tetapi tidak melebihi 30 ppt.Seaweed (Gracilaria verrucosa) has been cultivated in acid sulfate soil-affected ponds with relatively high quality and quantity of seaweed production. A research has been conducted to study water quality variables that influence the growth of seaweed in acid sulfate soil-affected ponds of Angkona Sub-district East Luwu Regency South Sulawesi Province. Cultivation of seaweed was done for six weeks in 30 selected brackishwater ponds. Seeds of seaweed with weight of 100 g were stocked in hapa sized 1.0 m x 1.0 m x 1.2 m. Dependent variable that was observed was specific growth rate, whereas independent variables were water quality variables including light intensity, salinity, temperature, pH, carbondioxide, nitrate, ammonium, phosphate, and iron. Analyses of multiple regressions were used to determine the independent variables which could be used to predict the dependent variable. Research result indicated that relative growth rate of seaweed in acid sulfate soils-affected brackishwater ponds ranged from 1.52% to 3.63%/day with 2.88% ± 0.56%/day in average. Among nine observed water quality variables, only five variables namely: nitrate, salinity, ammonium, phosphate and iron influence significantly on the growth of seaweed in acid sulfate soils-affected brackishwater ponds. The growth of seaweed in acid sulfate soils-affected brackishwater ponds of Angkona District East Luwu Regency, can be improved by using nitrogen-based fertilizers to increase ammonium and nitrate contents and also fertilizers which contain phosphorus to improve phosphate content to a certain level. Pond remediation to decrease iron content and also rearing seaweed at higher salinity (but less than 30 ppt) can also be alternatives to increase the growth of seaweed.

scholarly journals Transboundary geophysical mapping of geological elements and salinity distribution critical for the assessment of future sea water intrusion in response to sea level rise

2012 ◽  
Vol 16 (7) ◽  
pp. 1845-1862 ◽  
Author(s):  
F. Jørgensen ◽  
W. Scheer ◽  
S. Thomsen ◽  
T. O. Sonnenborg ◽  
K. Hinsby ◽  
...  
Keyword(s):  
Groundwater Flow ◽  
Sea Level Rise ◽  
Sea Level ◽  
Preferential Flow ◽  
Sea Water ◽  
Saline Water ◽  
Seismic Survey ◽  
Salinity Distribution ◽  
Geological Structures ◽  
The North

Abstract. Geophysical techniques are increasingly being used as tools for characterising the subsurface, and they are generally required to develop subsurface models that properly delineate the distribution of aquifers and aquitards, salt/freshwater interfaces, and geological structures that affect groundwater flow. In a study area covering 730 km2 across the border between Germany and Denmark, a combination of an airborne electromagnetic survey (performed with the SkyTEM system), a high-resolution seismic survey and borehole logging has been used in an integrated mapping of important geological, physical and chemical features of the subsurface. The spacing between flight lines is 200–250 m which gives a total of about 3200 line km. About 38 km of seismic lines have been collected. Faults bordering a graben structure, buried tunnel valleys, glaciotectonic thrust complexes, marine clay units, and sand aquifers are all examples of geological structures mapped by the geophysical data that control groundwater flow and to some extent hydrochemistry. Additionally, the data provide an excellent picture of the salinity distribution in the area and thus provide important information on the salt/freshwater boundary and the chemical status of groundwater. Although the westernmost part of the study area along the North Sea coast is saturated with saline water and the TEM data therefore are strongly influenced by the increased electrical conductivity there, buried valleys and other geological elements are still revealed. The mapped salinity distribution indicates preferential flow paths through and along specific geological structures within the area. The effects of a future sea level rise on the groundwater system and groundwater chemistry are discussed with special emphasis on the importance of knowing the existence, distribution and geometry of the mapped geological elements, and their control on the groundwater salinity distribution is assessed.

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