The implementation of the sustainable development objectives, requires additional knowledge about underwater landscapes of inland reservoirs. In this article, we assumed that (1) underwater landscapes of lakes are shaped mainly by the type of substrate and the assemblages of flora and fauna inhabiting a given reservoir; (2) vegetation is one of the most important elements of underwater landscapes, which dynamically reacts to environmental changes. This article presents the results of a study on the underwater landscapes of Lake Wielki Staw in the Karkonosze Mountains. Thirteen types of underwater landscapes were distinguished in the lake based on underwater inventory and spatial analysis using ArcGIS 10.7 software. The level of changes that occurred in the underwater landscape studied was determined using the underwater landscape structure maps for 2005, 2011, 2017, and 2021. In addition, the landscape change index ( LCI) for Lake Wielki Staw was determined for 2005–2011, 2011–2017, and 2017–2021. The results obtained indicate that underwater landscapes in lakes, similarly to terrestrial landscapes, are dynamic and subject to changes. In the case of Lake Wielki Staw, the changes in the range of Isoëtes lacustris communities in individual parts of the lake limited the differences in the area of all types of underwater landscapes distinguished. This allows us to use underwater vegetation inhabiting a given reservoir as an indicator of changes in underwater landscapes. Keywords:

Although Indonesia has recorded good performance in its national economic development, especially in the agriculture sector during the Covid-19 pandemic, the impact of the pandemic on farming and food systems has not been evaluated yet. This study has evaluated the resilience of the two dominant existing farming systems in West Timor, i.e. (i) wetland farming system and (ii) dryland farming system. This research aims to understand the resilience of farming after the Covid-19 pandemic and to develop strategic policies that could be adopted to increase the resilience of the farming system in West Timor. A quantitative analysis using the Structural Equation Modelling (SEM) was employed to evaluate the relationship and impact of the following seven generic aspects: labour movement, sustainability, economy, socio- culture, output markets, input markets, farming system resilience, and 27 reflective indicators. The analysis shows that dryland farming systems are more resilient than wetland farming systems. It might be understood from the size of the regression coefficient, as the impact of exogenous construct variables of the environment, socioculture, input, and output on the resilience of dryland farming systems is more significant than on wetlands. Economic performance rather than labour movement factors will create better resilience of farming systems for wetland or dryland after the Covid-19 pandemic. Finally, the economic recovery process and the ongoing input supply mechanism after the Covid-19 pandemic have increased the resilience of the dryland food system more than the resilience of the wetland farming system.

This study aimed to analyse the effect of anthropogenic activities on the spatial distribution of total nitrogen (TN) and total phosphate (TP) in Lake Maninjau, Indonesia, during the dry season. Sampling was carried out at ten observation locations representative for various activities around the lake. Cluster analysis and ANOVA were used to classify pollutant sources and observe differences between TN and TP at each site. Concentrations of TN and TP are categorised as oligotrophic-eutrophic. The ANOVA showed spatially that some sampling locations, such as the Tanjung Sani River, floating net cages, and hydropower areas have different TN concentrations. At the same time, TP levels were consistently significantly different across sampling sites. ANOVA and cluster analysis confirmed that floating net cages were the first cluster and the primary contributor to TN and TP. The second and third clusters come from anthropogenic activities around the lake, such as agriculture, settlement, and livestock. The fourth cluster with the lowest TN and TP is the river that receives the anthropogenic activity load but has a high flow velocity. The cluster change analysis needs to be conducted when there are future changes in the composition of floating net cages, agriculture, and settlements.

The article demonstrates the results of a study of the landscape structure of the Chornobyl Radiation and Ecological Biosphere Reserve (Ukr.: Chornobylskyi radiatsiino-ekolohichnyi biosfernyi zapovidnyk – ChREBR). Because of radioactive pollution, a sharp drop in human activity, and the granting of the territory the status of a protected object, the process of area rewilding took on certain characteristics and led to the return of ecosystems’ natural processes. The studies cover a 7-year period from 2016 to 2022, i.e., from the moment this territory was granted protected status. That territory was abandoned by people more than 37 years ago and the former rural and urban landscapes have either already been transformed or are in the process of being transformed into natural ones. The scale of forest massifs has changed during the previous seven years, which has caused increased pasture overgrowth. huge forest massifs have been lost because of enormous forest fires and floods, particularly along the Pripet and Uzh rivers. Semi-natural successions occur in the gardens, and wooden homes are almost extinct. From orbit, a number of communities no longer resemble settlements. They are cloaked in bushes and trees instead. For places that have been ploughed, the same holds true. The last seven years show that change is happening more slowly than in the decades before. The pattern of natural processes in ecosystems, including periodic fires, the blocking of reclamation channels, and other factors, is the primary driver of changes in the composition of the land cover.

Irrigation network maintenance is very important to ensure the function of irrigation run well. Therefore, maintenance fee is necessary to maintain the irrigation network. The problem is the maintenance cost of irrigation network is expensive, the second highest cost after rehabilitation costs. Thus, participation of farmers in irrigation network maintenance is essential. One of participation by farmers is in the form of regular fees. This study aims to determine the number of fees farmers are willing to pay to maintain irrigation networks through the willingness-to-pay approach. This study was conducted in the irrigation area of the Gonggang reservoir in Magetan District. The subject is farmers who use irrigation – the data collection technique used by observation, interview, questionnaire, and documentation. The data analysis technique used is the contingent valuation method with steps (1) determining the hypothetical market, (2) obtaining bids, (3) estimating average willingness to pay, (4) estimating bid curves, and (5) aggregating data. The result shows that the amount of farmers’ willingness to pay the maintenance fees for irrigation networks at Gonggang reservoir irrigation area in Magetan District by using the contingent valuation method is IDR 90,621 (USD 5.45) for each hectare for each planting period with total willingness to pay in the population of IDR 116,188,708 (USD 7,951.59) for each planting period.

Coastal areas face greater risk in terms of health and the environment. They are the most vulnerable to impacts resulting from climate change. Coastal areas with higher population density also have more environmental problems, such as natural disasters. Environmental health risks from chemicals and microbes continue threatening people living on small islands. Therefore, this study aims to: 1) conduct a chemical risk analysis of heavy metals Pb, Cr(VI), and Ni; 2) analyse the microbial risk posed by drinking water consumed daily by people on small islands. A method used to analyse the chemical risk of heavy metals was the environment health risk assessment (EHRA), whereas to analyse the microbial risk in small islands, the quantitative microbial risk assessment (QMRA) was used. The results showed that the concentration of heavy metals in drinking water was <0.0012 mg∙dm–3 for Pb, <0.01 mg∙dm–3 for Cr(VI), and <0.0019 mg∙dm–3 for Ni. The three heavy metals showed worrying results. Assessment and obtained risk quotient were less than one (RQ < 1) in all samples. Meanwhile, the microbial analysis found Escherichia coli, Acinetobacter calcoaceticus, Enterobacter sp ., and Citrobacter sp ., with risk characterised from low to high. Risk management is needed to control environmental health risks posed by heavy metals and the microbiological characteristics of drinking water on the small islands of the Spermonde Archipelago.

This paper presents the results of a laboratory study on the discharge capacity of sharp-crested weirs fitted with a horizontal edge in pipes during open-channel flow conditions and clean water used to measure the outflow. Such sharp-crested weirs are mounted in pipes and are used to control the inflow to separators. The stream profile does not correspond to the profile given by Bazin for sharp crested weirs in channels. A desired location of the water level measurement point for flow rate calculations was provided. Discharge curves were identified for three sharp-crested weirs of 0.0465, 0.0634 and 0.0771 m in height, installed in the pipe of 0.1534 m in diameter and inclinations of 0.5 and 1.0%. The discharge curves for weir flow with free nappe does not show a significant effect of the pipe slope on the weir discharge capacity. The non-dimensional formulas for the discharge capacity of the sharp-crested weir were found as general polynomial regressions. The results indicate that the calibrated sharp-crested weir with a horizontal edge placed in a pipe can be used to control the flow. Due to the scale effect, relationships obtained from the calibration cannot be generalised to other pipe diameters and weirs heights than those analysed.

The main purpose of the article is to develop a multifactorial model for rapid assessment of the efficiency of biological wastewater treatment reactors. A mathematical model of the process of biological wastewater treatment has been developed based on: changes in the concentration of organic contaminants in the bioreactor over time, taking into account the uneven flow of wastewater to the treatment plant, the process of substrate entering the bioreactor (different amounts may enter at different times). The software implementation of the proposed algorithm for solving the corresponding model problem in Python is carried out. The results of computer experiments on the study of the efficiency of wastewater treatment in biological treatment reactors for different operating conditions of facilities are presented. In particular, such processes were considered with taking into account the unevenness of the load, because the maximum cleaning loads are in the morning and in the evening. The task was solved to simulate a real situation and show how cleaning takes place at the maximum load at a certain time of the day. The results obtained will be useful for calculations in the design of biological treatment facilities or in the reconstruction of existing bioreactors for their prospective operation under new operating conditions.

In the heart of Moroccan oases, date palm trees stand as the lifeblood of local communities, serving as both a livelihood cornerstone and a dietary treasure trove. Morocco has long been a leading date fruit producer. Yet, amidst the palm groves, several environmental, technical, and socio-economic challenges have threatened the sustainability of this ancient crop. This study assesses the constraints and limitations of the date palm production system in Tafilalet oases that have kept this crop from reaching its full potential. A total of 56 producers were interviewed using an open- closed survey, illuminating interviews with key informants, dynamic focus group discussions, and direct observations in palm groves. The findings reveal that primary restrictions and barriers impeding the progress of this sector are: producers’ moderate education level and the limited adoption of technological innovation, few opportunities given to young producers, palm groves’ fragmentation, poor management of date fruits, low imports of the necessary inputs (fertilisers, irrigation, etc.), and the poor organisation of the marketing circuit (storage and packaging). Advocate renewed commitment to preserve and modernise palm groves, blending heritage with modern practices for thriving, sustainable date palm production. It is entirely conceivable to produce organic dates in the region since producers use a few quantities of chemical products, notably fertilisers and phytosanitary products.

This paper presents the results of a study on the level of nitrate leaching from the 0–30 cm layer of grassland (GL) soil in the Lublin Voivodship during the winters of 2018/2019, 2019/2020 and 2020/2021. The amounts of leached nitrates were determined using the Burns model. For the calculations based on this model – directly and indirectly, the results determination of residual nitrate nitrogen, texture and organic matter in GL soils, obtained within the framework of agricultural monitoring of soils by the National Chemical and Agricultural Station (KSChR), and results of system meteorological measurements conducted by the Institute of Meteorology and Water Management – National Research Institute (IMGW-PIB) were used.
The analysed soil samples were taken from 39 permanent control and measurement grassland sites. The research discovered in particular that:
– the average leaching of nitrate nitrogen from GL mineral soil in the three analysed periods was 16.2 and 5.1 kg N∙ha–1 from organic soil;
– on average, in autumn during the entire study period, 55.3% of NO3-N leached from the 0–30 cm layer of GL mineral soil, and 27.3% from organic soil;
– among different agronomic categories of mineral soil, the highest leaching of NO3-N was recorded from medium soil (17.4 kg N∙ha–1) and the lowest from heavy soil (11.5 kg N∙ha–1);
– individually determined values of NO3-N leaching from soil varied significantly from 0 to 68.5 kg N∙ha–1 for mineral soil and from 0.1 to 23.65 kg N∙ha–1 for organic soil.

Phytolith-occluded carbon (PhytOC) is highly stable, and constitutes an important source of long-term C storage in agrosystems. This stored carbon is resistant to the processes of oxidation of carbon compounds. In our research phytolith content in barley (Estonia) and oat (Poland) grain and straw was assessed at field trials, with Si as a liquid immune stimulant OPTYSIL and compost fertilisation. We showed that cereals can produce relatively high amounts of phytoliths. PhytOC plays a key role in carbon sequestration, particularly for poor, sandy Polish and Estonian soils. The phytolith content was always higher in straw than in grain regardless of the type of cereals. The phytolith content in oat grains varied from 18.46 to 21.28 mg∙g−1 DM, and in straw 27.89–38.97 mg∙g−1 DM. The phytolith content in barley grain ranged from 17.24 to 19.86 mg∙g−1 DM, and in straw from 22.06 to 49.08 mg∙g−1 DM. Our results suggest that oat ecosystems can absorb from 14.94 to 41.73 kg e-CO2∙ha−1 and barley absorb from 0.32 to 1.60 kg e-CO2∙ha−1. The accumulation rate of PhytOC can be increased 3-fold in Polish conditions through foliar application of silicon, and 5-fold in Estonian conditions. In parallel, the compost fertilisation increased the phytolith content in cereals.

The paper is designed to present a method to estimate greenhouse gases (GHG) uptake or emissions in the absence of data for peat bog areas (GEST method). The paper presents the research results produced by a project on “Limiting CO2 emissions via the renaturalisation of peat bogs on the Eastern and Central European Plain”. The study area consisted of three peat bogs: Kluki, Ciemińskie Błota, and Wielkie Bagno (Słowiński National Park). The GEST method relies on the estimation of gas emissions on the basis of vegetation and water levels and greenhouse gas coefficients for each given habitat type provided in the research literature. The greenhouse gas balance was calculated for a baseline scenario assuming the lack of human impact and for a scenario taking into account human impact in the form of peat bog preservation. Initial research results indicate that there is a total of 41 GESTs in the studied bog areas and that a reduction in CO2 emissions of approximately 12% will occur following what is known as renaturalisation by raising the groundwater level, felling of trees across the bog, and making changes in habitats.

This article introduces a groundwater vulnerability assessment model that utilises the fuzzy analytic hierarchy process (FAHP) in the Wadi AlHasa catchment, Jordan. The assessment takes into account both geomorphological and hydrogeological variables, employing a comprehensive methodology that integrates various parameters. To evaluate the catchment, the study employs remote sensing and Geographic Information System (GIS) techniques. The analysis of the digital elevation model enables the creation of a map illustrating the diverse geomorphology of the catchment. This geomorphology significantly influences drainage density, direction, and the spatial distribution and intensity of flash flood events. Moreover, the study develops and maps a fuzzy FAHP DRASTIC vulnerability index, which proves to be a valuable tool for assessing the susceptibility of groundwater resources to contamination. The unique feature of the index is its ability to incorporate uncertain or subjective data, providing a means to evaluate the significance of various influencing factors. This information serves as critical support for decision-making and management efforts geared towards safeguarding and enhancing groundwater resources. Within the study area, the DRASTIC vulnerability index values span from 0.08325 to 0.28409, with 18% of the site exhibiting a high vulnerability rate. Additionally, the article implements a managed aquifer recharge model (MAR), with 31% of the area falling into MAR classes. Among these, 22.1% are classified as a high MAR class, while 0.7% belong to a very high MAR class. These findings underscore the feasibility of MAR projects in regions with limited water resources.