For more than ten years a dynamic and intensive development has been observed in spatial information technology combining elements of geoinformatics with data from various sources in order to create elaborate, often interdisciplinary and multifunctional compilations.

The progressing implementation of IT solutions with reference to resources and related trends to make public infor-mation that is useful to a wide group of recipients are reflected in multimedia information materials of many public institutions and private businesses. An example of using electronic technologies in the presentation of spatial data of national parks is widely available geoportals, interactive maps and other cartographic or paracartographic visualizations offering various tools allowing the utilisation of spatial information resources.

This publication aims at a multilevel analysis of the availability of network services, as defined in Directive 2007/2/EC of the European Parliament and of the Council of 14 March 2007 establishing an Infrastructure for Spatial Information in the European Community,to all the existing geoportals of Polish national parks and a review of additional functions offered by the map services of all 23 Polish national parks that may be useful to users. As a result of research, tables and descriptions comparing the functions of the analysed geoportals were compiled and additional practical tools observed in other services were described. In addition, based on the comparisons, a concept of geoportal optimization was developed taking into account all categories of spatial information services and optional functions.

Statistical analysis is helpful for better understanding of the processes which take place in agricultural ecosystems. Particular attention should be paid to the processes of crops’ productivity formation under the influence of natural and anthropogenic factors. The goal of our study was to provide new theoretical knowledge about the dependence of vegetable crops’ productivity on water supply and heat income. The study was conducted in the irrigated conditions of the semi-arid cold Steppe zone on the fields of the Institute of Irrigated Agriculture of NAAS, Kherson, Ukraine. We studied the historical data of productivity of three most common in the region vegetable crops: potato, tomato, onion. The crops were cultivated by using the generally accepted in the region agrotechnology. Historical yielding and meteorological data of the period 1990–2016 were used to develop the models of the vegetable crops’ productivity. We used two approaches: development of pair linear models in three categories (“yield – water use”, “yield – sum of the effective air temperatures above 10°C”); development of complex linear regression models taking into account such factors as total water use, and temperature regime during the crops’ vegetation. Pair linear models of the crops’ productivity showed that the highest effect on the yields of potato and onion has the water use index (R2 of 0.9350 and 0.9689, respectively), and on the yield of tomato – temperature regime (R2 of 0.9573). The results of pair analysis were proved by the multiple regression analysis that revealed the same tendencies in the crop yield formation depending on the studied factors.

The potential of organic wastes in Ukraine for biogas production and the prospects of using the family-type biogas plants for this purpose are shown. In the biogas laboratory of the Ukrainian National Forestry University the efficiency of the anaerobic mesophilic digestion of chicken manure of Poltava poultry farm, Kamianets-Podilsky poultry farm and sewage sludge from Lviv wastewater treatment plant (WWTP) was investigated. Different integral indicators of the biogas production and significantly different dynamics of its formation over time were obtained for three investigated substrates. The value of average specific biogas production from the sewage sludge of Lviv WWTP is 0.494 dm3∙(day∙kg FM)–1, which is 5.1 times more comparing the chicken manure of Kamianets-Podilsky poultry farm and 8.0 times more than for the chicken manure of Poltava poultry farm. Strong negative effect of antibiotic treatment of chickens on methane contentin the obtained biogas was established experimentally.

Lysimeters represent the ideal tool for direct measurement of soil water balance components in soil profiles. Changes in the water content in a soil monolith can be measured with sufficient accuracy by the precise lysimeter weighing system.Water content changes in soil monolith as derived from lysimeter mass represent one of the basic water balance compo-nent. This paper deals with the development and comparison of individual soil water balance components in two different soil profiles from the Easter-Slovakian-Lowland. Two lysimeter vessels were filled monolithically with two different soil profiles covered with grass: one sandy soil profile from locality Poľany and one silty-loam soil profile from locality Vysoká nad Uhom. A constant groundwater level of 1 m below ground level was maintained in both soil profiles. Under the same meteorological conditions, all differences in the development of water balance components were caused only by the differences in soil profiles. The actual evapotranspiration and water flows at the bottom of the soil profiles were compared. Sandy soils are generally considered to be more prone to drought than silty-loam soils. Under the specific conditions of this experiment (maintaining a constant groundwater level) the opposite was shown, when the silty-loam soil profile was more prone to drought than sandy soil profile. Sandy soilprofile from Poľany reacted more quickly to precipitation (or evaporation). Due to the higher hydraulic conductivity of the sandy soil compared to the silty-loamy soil, the groundwater level response to external stimuli was much faster.

Improving water productivity (WP) through deficit irrigation is crucial in water-scarce areas. To practice deficit irriga-tion, the optimum level of water deficit that maximizes WP must be investigated. In this study, a field experiment was con-ducted to examine WP of the three treatments at available soil water depletion percentage (����) of 25% (reference), 45% and 65% using a drip irrigation system. Treatments were arranged in a randomized complete block design. The water deficit was allowed throughout the growth stages after transplanting except for the first 15 days of equal amounts of irrigations during the initial growth stage and 20 days enough spring season rainfall during bulb enlargement periods. Physical WP in terms of water use efficiency (WUEf) for treatments T1, T2, and T3 was 9.44 kg∙m–3, 11 kg∙m–3and 10.6 kg∙m–3 for mar-ketable yields. The WUEf and economic water productivity were significantly improved by T2 and T3. The WUEf differ-ence between T2 and T3 was insignificant. However, T2 can be selected as an optimal irrigation level. Hence, deficit irriga-tion scheduling is an important approach for maximizing WP in areas where water is the main constraint for crop produc-tion. The planting dates should be scheduled such that the peak water requirement periods coincide with the rainy system.

The pressure on the use of water and climate change has caused a decreased availability of water resources in semi-arid areas in the last decades. The Setif Province is one of the semi-arid zones of Algeria as it receives an average less than 400 mm∙year–1. The question of the evolution of demographic pressures and their impacts on water resources arise. By applying WEAP software (water evaluation and planning), the aim is to develop a model of water resources management and its uti-lization, assess the proportion of the resource-needs balance and analyse the future situation of water according to different scenarios. This approach allows to identify the most vulnerable sites to climatic and anthropogenic pressures. The estima-tion of the needs for drinking water and wastewater in the Setif Province has shown that these needs increase over time and happening when the offer is not able to cover the demand in a suitable way. It is acknowledged that there is a poor exploita-tion of water resources including underground resources, which translates into unmet demand in all sites of demand.

When high precision modelling is required, for example, with the estimation of suspended sediment load (SSL), data-driven models are preferred over physically-based numerical models for their real-time, short-horizon prediction ability. The investigation of SSL, as an important index in engineering practices assessment, like design and operation of the hydraulic structures not only shows the hydrological behaviour of the river, but also illustrates the valuable information about the water quality deterioration, surface-groundwater interaction and land-use changes of the watershed. The following data-driven methods were compared in order to predict SSL at the Seyra gauging station on the Karaj River in Iran: Fuzzy logic (FL), two adaptive neuro-fuzzy inference systems (i.e., ANFIS-GP and ANFIS-FCM models), an artificial neural network (ANN), and least squares support vector machine (LSSVM). Monthly average river flow and SSL data for 50 years were obtained from the Tehran Regional Water Authority (TRWA). The data was first divided into training, validation and test sets and the SSL was then predicted using the ANN, FL, ANFIS, and LSSVM models. The reliability of the applied models was evaluated by the correlation coefficient (R), root mean square error (RMSE), and mean absolute error (MAE). The results showed that the ANFIS models outperformed the ANN, FL, and LSSVM models for predicting SSL using the given input and output data. Overall, the performances of the artificial intelligence models used in the present study were satisfac-tory in predicting the non-linear behaviour of the SSL.

The paper presents results from social research on the Polish business representatives potentially interested in using the floating buildings. The main purposes of the study were to assess the level of knowledge about floating buildings and diag-nose stimulants and inhibitors of their development in the hotel, catering, and water tourism industry.

Combining the quantitative and the qualitative methodology, research was conducted using an on-line survey (CAWI)and Focused Group Interviews (FGI). Both involved a non-probabilistic, purposive sampling to reach a specific subgroup of the industry: owners or employees of catering, hotel or water tourism companies having or considering having a floating building. The group included both new and long-standing companies using facilities on water or with direct and indirect access to the water.

The study identified stimulating and inhibitory factors broken down into internal (context-independent) and external (context-dependent) conditions. Results show that in Poland floating commercial buildings are a niche topic but also a de-velopable one. Although 71% of the respondents notice difficulties resulting from the insufficient infrastructure and 66.5% of them indicate the lack of legal regulations, they also see the potential of floating buildings: depending on the industry, from 90 to 95% respondents find them “definitely attractive” or “rather attractive”. The most common reason for rejecting floating development is the lack of attractive moorages in the area (43.5% answers).

The article presents two floating architectural structures developed in response to the needs of local communities. The first one – a river barge “Louise-Catherine” – was adapted in 1929 according to the design of Le Corbusier, one of the most influential architects of the first half of the 20th century, for the purposes of Salvation Army shelter docked on the Seine in Paris and it continued its operation as such until 1994. The second one – Bertha von Suttner state junior high school – was developed in a shipyard to serve as a school, which purpose it has been fulfilling since 1994 while moored on the Danube River in Vienna. The author’s intention was to describe both structures while highlighting common features as well as differences, and to analyse them in view of certain selected aspects. The background for the projects’ development was described account taken of different reasons and circumstances. Issues under analysis include decision making processes in terms of architectural programme, functions and spatial developments. The analysis also includes technical aspects such as structural developments, material and infrastructure – in terms of the floating Viennese school – account taken on safety of using a barge as a school establishment. A separate part of the article is dedicated to the issue of social reception, and incase of the former Salvation Army shelter – actions aimed at the protection of a historic structure.

The geographical location and climatic conditions of Ukraine cause the active development of land reclamation, as it enables to ensure stable and high yields. The complexity of forecasting in this area, namely the dependence of the results onthe changing weather and climate conditions, does not allow to effectively use the standard instruments for justifying the investment for agricultural and land reclamation innovation.

The necessity of improving methodological approaches to evaluating the effectiveness of investments in projects in the field of agricultural production and land reclamation was substantiated. The proposed approaches were tested on the ad-vanced technology of water treatment in irrigation based on using a vibrating gravitation filter enabling to perform simultaneously the processes of water treatment and filter element regeneration.

The obtained results clearly show that the advancedtechnology of irrigation water treatment and the developed for this technology design of the vibrating gravity filter are cost-effective. The current payback period for irrigation projects when using the purified water under this advanced technology is 5 years. It is the same as for the irrigation projects when using clean irrigation water.

Thus, our proposed approaches to the evaluation of investments in new water treatment technologies applied in irriga-tion enable to adapt the modern methodology of analysis of economic and investment efficiency of projects to the domestic needs of agricultural production, namely to take into account the impact of changing weather and climate conditions on the resulting economic parameters.

Tropical regions such as Java, Indonesia, still lack publication of soil water retention (SWR) information, particularly at upper Citarum watershed. The SWR is one of the critical elements in water storage and movement in the soil and very important to solve ecological and environmental problems. However, getting the access requires a lot of laboratory meas-urement that is time-consuming and expensive. Therefore, utilizing pedotransfer functions (PTFs) to estimate the water in the soil is needed. This study aims to define soil properties related to the SWR and to evaluate the performance of existing PTFs in predicting SWR. The study was carried out at agroforestry land system soil at upper Citarum watershed, Indonesia. Ten point and two continuous existing PTFs developed for tropical regions were applied in this study. Pearson's correlation (r), mean error (ME), root mean square error (RMSE), and modelling efficiency (EF) were used for evaluation. Cation exchange capacity (CEC), organic carbon (OC), bulk density (BD), and clay were considered as potential soil properties for soil water retention prediction. The performance of PTFs by MINASNY, HARTEMINK [2011] at matric potential of –10 kPaand BOTULA [2013] at matric potential of –33 kPa and –1500 kPa were recommended for point PTFs, while PTFs by HODNETT, TOMASELLA [2002] was for continuous PTFs in predicting SWR. The accuracy of the point PTFs is almost better than the continuous PTFs in predicting SWR in agroforestry land system soil at upper Citarum watershed, Indonesia.

Formation of cities was always dependent on water. Location over the water areas gave the opportunity for develop-ment and increase of prosperity. And although water was also a threat and cause of damage, the benefits of its neighbour-hood prevailed. Today, the challenge for developing cities is a climate change observed in recent decades, which results in violent natural phenomena, e.g. floods and hurricanes. One of the main problems faced by residents of housing estates lo-cated on the water is the increasing risk of flooding. Actions are taken to adapt the functioning of the urban structure and buildings to new water conditions. Currently, the process of floodplain development is progressing on a larger scale. This phenomenon is intensifying and as a result many housing estates are created in areas exposed to flooding. The approach to flood issues in the context of architecture and spatial planning has evolved in recent decades. The new water paradigm is expressed in striving to keep it in place.

How did the settlement in the floodplains look once and today in Warsaw? The research study was preceded by a his-torical feature and then the article drew attention to the ways of shaping new housing estates in flood areas in Warsaw. Us-ing the case study method, new housing estates developed in the flood plains have been analysed, with a listing of their strengths and weaknesses and the assessment of solutions. Issues were discussed on how to protect the buildings from the harmful effects of water. On the basis of the conclusions from the Warsaw case study, project guidelines for floodplains in Warsaw were developed, the aim of which was to identify the most important priorities in the development of floodplains and increase the security of investment arising in these areas.

The Land and Property Register (LPR) also called the Cadastre by the legislator should function in accordance with regulations in force, meet expectations of the public and provide universal access to Register data for its users. Beyond any doubt, credibility and usefulness of data in this public register are affected by the manner it is kept, which generally in-cludes active and passive approach. If the LPR is kept in an active manner and constantly up to date, its data is very useful. The qualitative aspect of the land and buildings database’s records establishes the calculation accuracy of the owners’ land parcels evidenced in the Land and Mortgage Registers, which protect the ownership right to the property. In order to ensure that the plot of land is unequivocally and correctly measured, it is necessary to establish breakpoints of the parcels’ bounda-ries in the presence of the interested parties.

Research conducted on the possibility of using the unmanned aerial vehicle (UAV) for measuring purposes indicates immense probability where this technology may be used for the selected details of group I (most accurately located) in modernization of land and buildings registers.

MIKE SHE software was used to estimate recharge into the aquifers of Ogun and Oshun Basins. Abeokuta within the Ogun Basin and Oshogbo in the Oshun Basin are subdivided vertically into two components: atmosphere, and unsaturated zone. The atmosphere zone comprises of rainfall and potential evapotranspiration, while the unsaturated zones, comprises of the Basement Complex and Sedimentary rock. Daily records from two rainfall stations, Oshogbo station (2008–2011) and Abeokuta station (2010–2014) water years were obtained for simulation of groundwater recharge processes using MIKE SHE model. The simulation results showed that daily groundwater recharge is influenced by rainfall and ranges from 0 mm∙day–1 in January when there was an insufficient rainfall in the two stations to 10.89 mm∙day–1 in Abeokuta and 29.85 mm∙day–1 in Oshogbo in the month of August when the soils had attained field capacity. The study found out that there are more daily groundwater recharge in Oshun basin compared to that of Ogun basin. This was alluded to more rain-fall and less evapotranspiration recorded at Oshun basin as compared to Ogun basin coupled with the sedimentary soil which allows more movement of water into the aquifer of the basin. It is recommended MIKE SHE model should be used to estimate recharge in other basins in Nigeria and Africa for quick and effective daily recharge calculations to permit better and scientific decision making in these areas.

This study aims to evaluate changes in the frequency and severity of historical droughts (1980–2018) and then model future droughts occurrences (2019–2099) in the Lepelle River Basin (LRB), using Intergovernmental Panel on Climate Change (IPPC) General Circulation Model (GCM) simulations for two representative concentration pathways (RCP8.5 and RCP4.5). Firstly, the present-day and future hydrology of the LRB are modelled using the weather evaluation and planning (WEAP) model. Mann–Kendall tests are conducted to identify climate trends in the LRB. The reconnaissance drought in-dex (RDI) and the streamflow drought index (SDI) are employed to explore hydro-meteorological droughts in the Lepelle River Basin, South Africa. The RDI and SDI are plotted over time to assess drought magnitude and duration. The simulated temporal evolution of RDI and SDI show a significant decrease in wetting periods and a concomitant increasing trend in the dry periods for both the lower and middle sections of the LRB under RCP4.5 as the 22nd century is approached. Lastly, the Spearman and Pearson correlation matrix is used to determine the degrees of association between the RDI and SDI drought indices. A strong positive correlation of 0.836 is computed for the middle and lower sections of the LRB under the RCP8.5 forcing. Further findings indicate that severe to extreme drought above –2.0 magnitude are expected to hit the all three sec-tions of the LRB between 2080 and 2090 under RCP8.5. In the short term, it is suggested that policy actions for drought be implemented to mitigate possible impacts on human and hydro-ecological systems in the LRB.

Drought is known as a normal part of climate and including in a slow-onset natural hazard which may have several im-pacts on hydrology, agriculture, and socioeconomic. Drought monitoring, including its severity, spatial and duration is re-quired and becomes an essential input for establishing drought risk management and mitigation plan. Many drought indices have been introduced and applied in regions with different climate characteristics in the last decades. This paper aims to compare standardized precipitation index (SPI) and rainfall anomaly index (RAI) along with standardized streamflow index (SSI) in Pekalen River Basin, East Java, Indonesia. The statistical association analyses, included the Pearson correlation (r), Kendal tau (τ), and Spearman rho (rs) were performed to examine the degree of consistency between monthly and annual drought index of SPI and RAI. Additionally, the comparative analysis was performed by overlapping both monthly and an-nual drought index from the SPI and RAI with the SSI at hydrological years. The study revealed that the characteristic of the annual drought index between the SPI and RAI exhibits pattern similarity which indicated by the high correlation coeffi-cient between them. Further, the comparative analysis on each hydrological year showed that the SPI and RAI were very well correlated and exhibited a similar pattern with the SSI. Overall, the SPI shows better performance than the RAI for es-timating drought characteristic either monthly or annual basis. Hence, the SPI is considered as a reliable and effective tool for analyzing drought characteristic in the study area.

The paper attempts to assess the possibility of using typical check structures equipped with sluice gates to measure the volumetric flow rate in the irrigation channels. The submerged flow through the sluice gate was considered. Experimental tests on a model of typical check structure in 1:2 scale were carried out. The conducted analyzes confirmed the possibility of using discharge equation for submerged flow through the sluice gate to estimate the water flow rate in the irrigation channels. In order to obtain accurate values of flow rate, the downstream tailwater depth should be measured at the appropriate distance from the sluice gate. For different values of gate-opening height, the downstream water depth measurement locations allowing for a correct flow estimation were indicated. This approach might be useful in calibration of other designs of sluice gates for flow measurements.

Estimation and application of water retention curves in heavy soils have own specifics. The reason for these specific properties is the composition of the high clay texture. This is manifested by volume changes of soil depending on moisture. Up to 40% change in the volume compared to the saturated state was recorded in the conditions of the East Slovakian Lowland. The results described in this work are based on research work carried out in the East Slovakian Lowland and represent an analysis of selected 42 samples out of a total of 250 samples in which laboratory measurements of soil water retention curves and volume changes were performed. Selected samples represent the localities Senné and Poľany. Volumetric changes were measured in a laboratory by measuring the dimensions of soil samples. Appropriate changes in the volume of soil samples should be measured when determining moisture retention curves. Neglecting this physical effect leads to a distorted determination of the water retention curves in heavy soils. In the laboratory measurement of water retention curves points, changes in the volume of the sample were measured in the range of 0.24–43.67% depending on the soil moisture potential during drainage. In the case of neglecting the effect of shrinkage during the drainage of samples, a certain error is occurring in the calculation of the volumetric moisture. The range of this error was 1–13% of volumetric moisture.

There are several springs with the large discharge around the Watuputih Karst Hills area that playing a crucial role in supplying water for both domestic and irrigation needs. The springs are located in the fault and fold zones of the Rembang anticlinorium system. This study was designed to determine the characteristics of karst aquifers from one year of monthly spatio-temporal data on discharge parameters and physico-chemical properties (temperature, pH, EC, Ca2+, Mg2+, HCO3–) of the four major springs, namely Brubulan Tahunan, Sumbersemen, Brubulan Pesucen, and Sendang Sayuran. It used sta-tistical calculations to characterize spring discharge and hydrochemical variations, as well as bivariate correlation analysis and flow-duration curve (FDC). The variability index (Iv), variability (V), and spring coefficient of variation parameters (SCVP) classified Brubulan Tahunan and Sumbersemen as springs producing stable, fairly constant discharge with low variations but characterized Brubulan Pesucen as having unstable, varying discharge with moderate variations. The results showed gently sloping hydrograph, low variations in discharge and hydrochemical properties, a relatively prolonged re-sponse of discharge and CO2-H2O-CaCO3 interaction to rainfall, and slope changes in the FDC. In other terms, although the springs are controlled by faults and folds, they have diffuse groundwater storage system in the form of densely fractured and porous media. These findings also indicate a less developed interconnected conduit, although Brubulan Pesucen is relatively more developed than Sumbersemen and Brubulan Tahunan. The geological structure and hydraulic gradient formed between the groundwater recharge and discharge areas are proven to control the amount of spring discharge actively.

The aim of the study was to compare the physical-chemical quality parameters of shallow groundwater quality in peat bogs of the Łęczna-Włodawa Lake District in the context of the occurrence of selected boreal species of plant relics: dwarfbirch (Betula humilis Schrank), downy willow (Salix lapponum L. ) and swamp willow (Salix myrtylloides L. ). Analyzes of shallow groundwater quality parameters included physical-chemical parameters: reaction (pH), electrolytic conductivity(EC), dissolved organic carbon (DOC), total nitrogen (TN), ammonium nitrogen (NH4), nitrite nitrogen (NO2), nitrate nitrogen (NO3), total phosphorus (TP), phosphate (PO4), sulfate (SO2), sodium (Na), potassium (K), calcium (Ca) and mag-nesium (Mg) by certified laboratory tests.

It was found that the natural hydrochemical specification of peat bogs is characterized by fluctuations associated with the dynamics of internal metabolism of peat ecosystems without the visible impact of anthropopressure. This is confirmed by the concentration of nutrients: TNat the study sites were within a broad range of mean values: 16.92–45.31 mg·dm–3; NH4 (0.55–0.76 mg·dm–3); NO2 (0.06–4.33 mg·dm–3); and NO3 did not exceed 0.2 mg·dm–3, and concentration of TP adopted mean values in a range of 0.22–0.42 mg·dm–3.

The studied physical-chemical factors of shallow groundwater were within the habitat preferences of the studied species, but in differentiated qualitative and quantitative ways determined optimal conditions for building the population of the studied species. Particularly values of TP lower than other obtained values in a range of: 0.08–0.32 mg·dm–3; PO4 = 0.1 mg·dm–3; TN = 2.2–21.2 mg·dm–3; NH4 = 0.1–0.46 mg·dm–3; DOC = 24.6–55.9 mg·dm–3, as well as higher than average pH values in a range of: 5.34–5.95 and concentration of Ca = 5.67–28.1 mg·dm–3 and Mg = 0.56–2.41 mg·dm–3, as well as EC = 72.1–142.3 μS·cm–1 can be treated as a condition favouring proper development of the population of dwarf birch. For Salix lapponum: a reduced level of values of nitrogen fractions (TN = 3.01–18.84 mg·dm–3; NH4 = 0.1–0.41 mg·dm–3), a reduced level of values of phosphorus fractions (TP = 0.09–0.44 mg·dm–3; PO4 = 0.1–0.44 mg·dm–3), part of ions (Ca = 4.39–19.63 mg·dm–3; Mg = 0.77–3.37 mg·dm–3), pH = 5.9–6.4, EC = 124–266 μS·cm–1 and DOC = 24.1–57.5 mg·dm–3. For the equally studied Salix myrtylloides, such conditions were met by: TP = 0.1–0.41 mg·dm–3; PO4 = 0.1–0.18 mg·dm–3, DOC = 27.5–50.9 mg·dm–3, pH = 5.3–5.94 andEC = 62.2–139.3 μS·cm–1.

Oxbow lakes occurring in floodplains are those natural elements that are subject to rapid changes, which may lead to their disappearance. These are extremely valuable ecosystems and landscape components, as well as water management units. However, they quickly disappear if they are not periodically fed with river water, which takes place especially when rivers are embanked. Such a situation occurs, among others in Warsaw, in the Vistula valley. There are many opportunities for the reactivation of oxbow lakes, including through technical activities. It is not always possible to restore the naturalvalues of the valley in urbanized areas, however, oxbow lakes can then also play a recreational role and they can fulfill an important task in improving the quality of life, being also an important element of the public space system. The author has carried out research related to land development projects of the new district located in the Vistula River valley in Warsaw (the Siekierkowski Arc). Many different design solutions have been proposed, taking as a leitmotiv the restoration of oxbow lakes, for example: (1) reconstruction of the water channel in the former watercourse with the boulevard along its fragment and with the public park in another part, (2) water supplying of the existing oxbow lake through the green and blue infrastructure system. The author presents few urban designs carried out under her direction for this area and shows that creative reactivation of oxbow lakes can improve water conditions, and be beneficial for the introduction of a new, attractive development.

Heavy metals like cadmium (Cd) and lead (Pb) are pollutants that are toxic, difficult to decompose and accumulate in biota. One of the biota that lives in the waters is mullet fish. This fish is demersal, has a relatively long life period, has a specific tolerance to the aquatic environment and highly consumable in Indonesia. Therefore need to know the metal content of Cd and Pb in water, sediments and mullet fish and their relationship in Indonesia. The study used a survey method with purposive random sampling at four stations, three replications. The study was conducted from June to November 2019. Analysis of data was descriptive, F-test and correlation. The results showed that the heavy metal content of Cd and Pb between stations in the water media, sediment and in mullet fish there was a significant difference. The highest Cd and Pb were showed in station III, coming from the oil industry, domestic waste and transportation activities. The heavy metal content of Cd and Pb in water, sediment and mullet fish (Planiliza subviridis) in the Donan River, Cilacap shows results exceeding the allowed threshold and danger to human health.