Land Development Planning Research Articles

The land development plan as a legal act and administrative instrument for planning and managing the development of the municipality. A legal, political and socio-economic study

The paper deals with the subject of the spatial development plan as a key instrument for managing the development of a municipality. The essence of the spatial planning process is presented, as well as the applicable legal rules and procedures for the creation of this document, together with a description of the competences of the various authorities and public institutions in the spatial planning process. It also presents a statistical view of the functioning of plans throughout the country. Particular attention was paid to the negative consequences of the lack of use of this instrument in the context of the development processes of territorial units. The analysis presented includes a legal analysis of planning processes, taking into account administrative proceedings, planning annuities and local development processes. The arguments presented above proving the extremely important role of spatial planning processes in improving the quality of life of local communities should be reflected in the number of communes in which such plans are in force, and more precisely, it is to indicate the area of the entire country covered by the adopted local plans.

Planowanie terenów rolniczych w Bułgarii - obecna funkcjonalność prawodawstwa i perspektywy

Development Planning for the Agricultural Territory is a problematic activity in Bulgaria in terms of the existing legal requirements. Bulgarian legislation contains certain gaps in regulating and technically ensuring the agricultural land planning. This is well settled in relation to the other types of territories like the Urban, Forest, and Protected ones, which planning rules and activities are regulated in details. The purpose of the paper is firstly to justify the necessity of improving and detailing the legal regulations for the agricultural land development planning, and secondly to suggest some expert approaches for improving and harmonization of legislation in connection with registration of the agricultural property by Agricultural Territory Development Plan (ATDP), Restored Property Map (RPM) and Cadastral Map (CM). The current legal grounds for planning development of the agricultural land in Bulgaria are presented and analysed. Lack of detailed regulations on their scope, content and operation have been found. It is also a matter of applicability of the newly created municipal CMs in settling land relations such as purchases and sales of land, inheritances, divisions, and changing the primary purpose of use of Agricultural Territory for construction. The completeness of CM with information about the quality of agricultural lands is still not regulated by Cadaster and Property Register Act. The paper contains specific proposals for amendments in Spatial Planning Act, Cadastral and Property Registry Act and Agricultural Land Ownership and Use Act.

Characteristics and Influencing Factors of Spatiotemporal Distribution of Rural Houses Construction Development in Mountainous Villages of China (1980–2019): A Case Study of Qingyuan Town

Rural house is a fundamental component of rural settlements, and understanding its construction and development characteristics is crucial for rural land use and development planning. This paper focuses on the spatiotemporal characteristics and influencing factors of Rural Houses Construction Development (RHCD) from 1980 to 2019 with a case study of Qingyuan Town in China. Based on the literature review and filed research, a set of evaluation indicators for RHCD was established. The article calculates RHCD indicators from temporal and spatial dimensions, uses the location entropy method to demonstrate the spatial distribution of indicators, and classifies the RHCD type of 14 villages in Qingyuan Town using clustering algorithms. It also analyzes the influencing factors of spatiotemporal distribution. The results show that the RHCD in Qingyuan Town exhibits typical characteristics of mountainous areas and aligns with the development trends of rural society in China. Population growth, geographical location, and economic development are the primary driving factors for the quantity indicator (Qi), while economic growth, construction technology, industrial development, and policy adjustments are the key factors influencing the form indicator (Fi). In future policy-making, greater emphasis should be placed on optimizing development strategies, improving data and monitoring systems, and integrating administrative strength with actual development needs.

Evaluation of Urban Land Suitability under Multiple Sea Level Rise Scenarios

Anticipated sea level rises from global climate change pose a significant flood risk to urban land. Evaluating urban land suitability under sea level rise scenarios is crucial for promoting sustainable development. Recent research has advanced the application of artificial intelligence and the integration of GIS with models, yet the impact of climate change on land suitability has often been overlooked. This study focuses on Xihu District in Hangzhou, utilizing the entropy weight and matter-element model to evaluate land suitability for urban development. The evaluation results were cross-verified with land use plans. A comprehensive analysis of potential flood risk to urban land in 2100 was conducted, considering varying degrees of sea level rise under Sustainable Development Scenario SSP1-2.6 and High-end Emission Scenario SSP5-8.5, as well as the scenario reflecting the most severe sea level rise during extreme climate events. The results indicate that more than half of the land in the study area is suitable for construction, aligning spatially with the current planned urban land. The analysis process of the matter-element model reflects the impact level of each indicator on urban land suitability, conveying information both spatially and numerically, thus enhancing accuracy. Scenario analysis reveals that approximately 10% to 20% of urban land in the study area could face flooding threats due to future sea level rises, primarily in the northern and southeastern regions. Recommendations for future land development and spatial planning strategies to address flood risk are discussed, aiming to alleviate the pressure on urban land in response to future climate change.

Land-Use Change Dynamics in Areas Subjected to Direct Urbanization Pressure: A Case Study of the City of Olsztyn

Urbanization is one of the most visible symptoms of global changes. This process has been driven by the evolution of life on Earth, and it gradually modifies the structure of land use. Urban development is the most apparent indicator and measure of urbanization. The demand for vacant land and sustainable spatial development plans require new methods that support decision-making in the process of changing land use in suburban areas. The aim of this study was to describe a methodology for identifying and localizing urban development boundaries with the use of fuzzy set theory, to evaluate the degree of urbanization, and to analyze the dynamics of land-use changes in areas subjected to direct urbanization pressure with the use of photogrammetric data for 2005, 2010, 2017, and 2022. A case study was conducted in the Polish city of Olsztyn. The study’s results determined the degree of urbanization of the areas in the [0, 1] range, as well as the dynamics of change in each of the twenty-four adopted forms of land use. The results indicate that the proposed methods are useful for identifying the rate and direction of urbanization, and can be applied to optimize and counterbalance the development of settlements and infrastructure.

Právna regulácia krajinotvorby na Slovensku ako prostriedok ochrany klímy

The article focuses on the implementation of landscaping as a purposeful activity of humans with the aim of creating and cultivating the environment around them. Landscaping is not only made up of activities with an impact on the immediate surroundings of a human, but also has a deeper social meaning – it affects the environment as a whole. However, it also has a significant impact on climate protection. Actions taken with the intention of protecting and improving the landscape that immediately borders the built-up area of municipalities in which humans reside can have a wider impact indirectly, but even directly, influence the climate. Although landscaping represents a separate and distinct professional activity, in the case of the Slovak Republic it is not a separate decision-making process in the field of public administration. However, its elements are present in other decision-making processes, such as land development or spatial planning. The ever-increasing voices after its codification point to the importance of this activity and the need to give it a clear legal framework, with the definition of the public interest and the goals that should be achieved during this activity. We believe that climate protection could and clearly should be among these objectives, as the measures taken in landscape design can have a direct effect on it. The article therefore focuses on the issue of landscaping and its legal definition, and also deals with whether landscaping represents an important means of climate protection. Furthermore, the article points out the individual possibilities of landscape design measures within the decision-making processes of public administration in the Slovak Republic. In the end, he brings some considerations de lege ferenda.

Geospatial Tool-Based Geomorphological Mapping of The Lower Kulsi Basin, India

Detailed geomorphological map of a region provides necessary information on landforms to understand the variations of surface and subsurface processes. Geomorphological maps prepared based on a combined geospatial and field-observation approach are preliminary data for precise, prompt, and efficient watershed-level planning. The Kulsi is a significant left-bank tributary of the Brahmaputra. It has potential for agricultural, land, and water resources, but the region needs to catch up due to frequent climatic-geomorphic hazards. Therefore, this article aims to prepare an object-oriented detailed geomorphological map using geospatial tools. High-resolution satellite images and a digital elevation model were used to generate the detailed geomorphological map of the studied area. The resultant map is verified with extensive fieldwork. The investigated basin is characterized by structural and denudation hills, anthropogenetic escarpment; pediment plain, older and young alluvial plain; active and older flood plain; islands and sandbar deposits, and highly sinuous river and natural and artificial surface waterbodies. The research can contribute to local governments' and communities' land and water resource development plans. Keywords: geomorphology, morphometry, satellite image, Geographic Information System

Finding Sprawl Factors and Pirate Development: Based on Spatial Analysis of Population Grid Changes from 2014 to 2022 in SMA, South Korea

This comprehensive study explores urban sprawl in the Seoul Metropolitan Area (SMA), emphasizing its rising intensity and complexity despite previous public-led planning efforts. The study aims to visualize the spatial patterns of sprawl and identify influencing factors through spatial regression analysis using grid-based population data created from actual population distributions. This approach fills a gap in the existing literature by moving beyond administrative-level analyses prone to ecological fallacies. This study scrutinizes the dynamics of population change in Seoul Metropolitan Areas (SMAs) in Korea over a decade, focusing on the predatory aspect of urban sprawl. Using grid-based population data and spatial regression analysis, the study finds that population growth is concentrated in unplanned areas with high development benefits. Three key hypotheses were examined: (1) Areas with high development potential, measured through factors like land prices and development plans, attract predatory development; (2) Improved transportation infrastructure encourages population inflow; (3) Non-urban land use, especially bare land, attracts population growth. The results offer important policy implications, particularly for preparing areas with low land prices and improving transportation infrastructures for future population influxes. Monitoring is particularly crucial in areas where development plans are already in place or where there is a high percentage of bare land.

Land Development Planning: New Principles and New Representations in the General Urban Plan of Parma

Since the entry of Emilia-Romagna Regional Law No. 24/2017 Disciplina regionale sulla tutela e l’uso del territorio, the processes guiding the development of the territory have profoundly changed, in principle, in the structuring through processes of participation and how contents are expressed and represented. Concepts such as the containment of soil consumption as a non-renewable resource; regeneration of urbanized territories; protection and enhancement of land, including agricultural land; protection and enhancement of historical and cultural elements; and promotion of greater levels of knowledge of the territory and its existing built heritage are the main principles of the law that give foundational importance to the entire process of forming the knowledge framework and strategic lines that structure General Urban Plans, which are designed to express planning contents through an ideogrammatic type of cartography. The analysis of the law and its contents also becomes an opportunity to reflect on the tools through which the governance of the territory is implemented, from GIS to web GIS up to the changes in the graphic language through which the planning principles are expressed, with specific reference to the planning tools of Parma, on which the new General Urban Plan (PUG) is being defined.

Ecological monitoring of urban thermal field variance index and determining the surface urban heat island effects in Lahore, Pakistan.

Lahore is the second major metropolitan city in Pakistan in terms of urban population and built-up area, making the city a more ideal place to form the surface urban heat island (SUHI) effects. In the last two decades, the considerable land-use conversion from a natural surface (vegetation) and permeable (waterbody) surface into an impervious (built-up area) surfacehas lead to an increase in land surface temperature (LST) in Lahore. The human thermal comfort (HTC) of the residents is alsoimpacted by the higher LST. The present study uses multi-temporal Landsat (5&8) satellite imageries to examine the ecological and thermal conditions of Lahore between 2000 and 2020. The ecological and thermal conditions of Lahore are assessed by calculating the urban heat islands and UTFVI (urban thermal field variance index), based on LST data which quantitatively assessed the UHI effect and the quality of human life. The outcomes establish that the urban built-up area has increased by 18%, while urban vegetation, vacant land, and waterbody decreased by 13%, 4%, and 0.04%, respectively. In the last 20 years, the mean LST of the study region has risen by about 3.67 °C. The UHI intensity map shows intensification and a rise in surface temperature variation from 4.5 °C (2000) to 5.9 °C (2020). Furthermore, the finding shows that the ecological and thermal conditions are worse in construction sites, transition zones, and urban areasin comparison to nearby rural areas. The lower UTFVI was observed in dense vegetation cover areas while a hot spot of higher UTFVI was predominantly observed in the areas of transition zones and built-up area expansion. Those areas with higher hot spots are more vulnerable to the urban heat island effect. The main conclusions of this study are essential for educating city officials and urban planners in developing a sustainable urban land development plan to reduce urban heat island effects by investing in open green spaces for urban areas of cities.

How far from the shoreline? The effect of catchment land use on the ecological status of flow-through lakes

Catchment land use/land cover (LU/LC) is one of the crucial determinants of the water quality and condition of biota in aquatic environments. The aim of this study was to investigate how LU/LC in lake catchments influences the physicochemical and biological indicators used to assess the ecological status of lakes in Poland and whether these relationships vary depending on the spatial range. We analysed the catchment LU/LC forms of 114 flow-through lakes in three spatial ranges, i.e., a 100 m-wide buffer strip (BUF100), the direct catchment (DIR), and the total catchment (TOT). The water quality and biological variables were derived from the state monitoring conducted in the period 2012–2013. The redundancy analyses (RDA) and the Monte Carlo permutation tests depicted that the strength in explaining the parameter followed the order: TOT > DIR > BUF100 for physicochemical parameters, DIR = TOT > BUF100 for phytoplankton indicators and BUF100 > DIR > TOT for macrophyte indicators. In the direct and total catchment, the proportion of arable lands was decisive in shaping the macrophyte and physicochemical status, while the proportion of artificial surfaces affected phytoplankton status. It was also found that forested buffer zones promoted good macrophyte ecological status. The other types of LU/LC, i.e., meadows and pastures, wetlands, and surface waters exhibited little to no or marginal impact on the physicochemical and biological indicators, regardless of the spatial scale considered. Our results contribute to the rational planning of land development in lake surroundings, including the design of protected areas for inland waters.

Predictive uncertainty assessment in flood forecasting using quantile regression

Abstract Floods and their associated impacts are topics of concern in land development planning and management, which call for efficient flood forecasting and warning systems. The performance of flood warning systems is affected by uncertainty in water level forecasts, which is due to their inability to measure or calculate a modeled value accurately. Predictive uncertainty is an emerging type of uncertainty modeling technique that emphasizes total uncertainty quantified as a probability distribution conditioned on all available knowledge. Predictive uncertainty analysis was done using quantile regression (QR) for machine learning-based flood models – Hybrid Wavelet Artificial Neural Network model (WANN) and Hybrid Wavelet Support Vector Machine model (WSVM) for different lead times. Comparing QR models of WANN and WSVM revealed that the slope, intercept, spread of forecast, and width of confidence band of the WANN model are more for each quantile indicating more uncertainty as compared to the WSVM model. In both models, with an increase in lead time, uncertainty has shown an increasing trend as well. The performance evaluation of inference obtained from QR models was evaluated using uncertainty statistics such as prediction interval coverage probability, average relative interval length (ARIL), and mean prediction interval (MPI).

Climate-altered Precipitation is more Important than Land Use when Modeling Ecosystem Services Associated with Surficial Processes.

Ecosystem services (ESs) associated with surficial processes may change according to shifts in land use, land cover, and climate parameters. Estimating these shifts can be important for land development planning, as urbanization alters soil processes that can manifest legacy effects. We employed the InVEST suite of models for sediment retention, nutrient delivery, and carbon storage to postulate how these ESs will change in the Upstate of South Carolina under future precipitation and land use and land cover (LULC) scenarios. We used the average precipitation from 1981-2010 and WorldClim precipitation projections for 2021-2040 and 2041-2060 to embody climatic precipitation shifts. For our LULC scenarios, we used 2011 and 2016 NLCD landscapes, then projected future LULC to hypothesize four future scenarios. We found that for the ES models that included both precipitation and LULC as inputs, precipitation dictated ES delivery far more heavily than land use or land cover. LULC scenarios produced consistent changes in ES delivery for all models except sediment export. Phosphorus and sediment exports increased between 2011 and 2016 due to LULC change, while nitrogen export stayed the same and carbon storage decreased. Land development that prioritizes forest cover will cause the least change in ESs, but allowing for continued forest loss to low-density development will have the most intense implications for ESs. Prioritization of land uses that preserve ESs associated with surficial processes will be critical to the longevity of agriculture and ecosystem integrity in this rapidly developing region. Land development planners should integrate consideration of ESs associated with surficial processes into future regional planning.

Multi-Dimensional Evaluation of Land Comprehensive Carrying Capacity Based on a Normal Cloud Model and Its Interactions: A Case Study of Liaoning Province

Studying land comprehensive carrying capacity (LCCC) is the foundational and key requirement for determining land development planning and urban spatial development patterns of a region. However, the traditional evaluation method discounts the fuzziness and randomness of the evaluation index and its results. The cloud model combines randomness and fuzziness to reveal the correlation between randomness and fuzziness using numerical feature entropy and is used to represent the granularity of a qualitative concept. This study used the Liaoning Province as the study area, and developed a multi-dimensional evaluation index system for LCCC using a normal cloud model. Based on this, the relationship between the different elements of geological condition, resources and environment, economic scale and urban construction were studied using the coupling coordination degree model that reflected not only the system interactions but also the strengths of its degree of coordination. Our results were as follows: (1) numerical feature entropy were evaluated to determine the carrying capacity level of the land, and comprehensive land carrying capacity evaluations were conducted in terms of both quantitative results and the reliability of the results, promoting the scientific application of uncertainty theory in the field of comprehensive land evaluation as well as carrying capacity. (2) Liaoning Province’s prefecture-level cities had distinctly different LCCC, demonstrating “low in the west and high in the east” spatial distribution characteristics. Cities with established economies and relatively strong infrastructures had larger comprehensive land carrying capacities. Overall, there was considerable consistency across the region, though the “low in the west and high in the east” spatial distribution characteristics affected the degree of coordination.

On the Way to Metropolitanization: Housing Clusters in Turkey

An increasing number of housing clusters have emerged because of the reconstitution of Turkish metropolitan municipalities, supported by the arrangements made in land development plans. Turkish metropolitans are determined by the administrative borders, while the world metropolitans are determined by their functional urban areas. Here, we aimed to evaluate the clustering capacity of metropolitan municipalities by focusing on the distribution of the residential occupation permits. Exploratory spatial data analysis was used to determine the core provinces of housing. The Moran Index was used to investigate the increase of clusters and this was cross-checked with the Spatial Lag results. We improved the recent land-use changes from rural plots to urban service parcels over the presence of the land development plans, including the transactions. Across the limited period studied, grifted patterns appeared. Clustering provinces enhanced the detection of construction that boosted urban development. Furthermore, a meshwork was revealed. In most developing countries, finding diverse and not tempered data sets in official sources is still a big problem. Moreover, open-data sources were limited in this study. In the search to prove uncontrolled urban growth fueled by construction activities, our research established an alternative way to read the metropolitan area network using occupancy permits, where the lack of data cannot be compensated.

Industrial and oil ports: case studies and theoretical approaches

Industrial and oil ports have been mainly developed, after the Second World War, with the birth of large industrial systems and they established during the second half of 20th century. Large ports are built close to the industrial areas. Heavy and oil industrial sectors need huge loading capacity, direct connections without constraints on shapes, lengths and unit of loads. The iron and steel industry, the petrochemical, the power plants, etc., determine the birth of the so-called second-generation ports, as defined by UNCTAD. The technical characteristics are the following: large yards close to the quays, oil terminals with sophisticated security systems, starting points for oil pipelines and power lines. The paradigm of the second-generation ports is: firstly, the industrial plant was settled and, then, the port was built for serving the industrial plant. The ships that arrive at the industrial ports are specialized. The oil tankers are born, with the subsequent variations of hull and technology, they evolve up to the LNG ships. The economic system is therefore defined in a simple way: eliminating the distances between the heavy industry plants and the loading/unloading points that allow international connections. The economic model has not been enough studied in its basic components given by the flows of goods from the port to the industries and vice versa.The paper is articulated into two main parts. The first one presents a critical analysis of some representative case studies of industrial and oil ports for each continental area. The second one presents the proposed theoretical approaches, based on Transport System Models (TSMs) introducing the multi-modal approach considering that in the examined ports there is a pipeline network other than a road network. The multi-modal TSM explains the relationship of industrial and oil ports with trade partners who have built their cargo transformation facilities in the closer industrial area. The approach can be extended to the sea and land networks used for the oil transport. The work may be considered a step able to open several directions to study the characteristics of oil and petrochemical ports and their connection with the industrial areas by means of TSMs. The use of TSMs allows transport planners to integrate industrial ports into land development plans and researchers to investigate the structure of TSMs applied to freight transport during which physical and economic (value modification) changes occur in goods.

An Assessment of Land Use/Cover Suitable for Peri-urban Green Space Development: an Example of an Integration of GIS with the Multi-Criteria Analysis (MCA) Approach

Land allocation priorities to urban green cover are usually neglected particularly in the countries of developing economies such as Turkey. Lack of urban green space can cause many social and physical problems among the residents. Therefore, urban planning and policy should incorporate suitable green land in the urban planning of cities to optimise the benefits obtained from urban green spaces. Land suitability analysis is a commonly used methodology which provides a framework for developing strategies in the planning of green land development. Two different approaches will be utilised for the assessment of suitability of land uses for urban agriculture, forest and natural vegetation in the Pendik district of Istanbul. Standardisation of values in criteria maps was done using the deterministic approach in the first case whereas fuzzy membership was utilised as an alternative in the second case. Analytical Hierarchical Process (AHP) was used for the weighting of sub-criteria and map layers were overlaid using the weighted linear combination using the GIS software. Geophysical factors, transport and services accessibility, land cover/use, blue and green amenities, soil properties, geology and erosion susceptibility are the main criteria selected for the assessment of urban green land suitability. The provision of suitable land for urban agriculture, forest and natural vegetation uses will provide a framework to the land use planning and decision support aimed at contributing to urban sustainable development.

Duży problem z cienką linią – linia zabudowy w planach zagospodarowania przestrzennego największych miast Małopolski

The building line designated in local land development plan is one of the important instruments for shaping urban space and the creation of spatial order. The aim of the study is to analyze the potential and real influence of this instrument on the formation of the compositional values of space. The analysis covered land development plans of the 3 largest cities in Lesser Poland. The analysis included the methods of defining the building lines and determining their course, including in relation to the rules of property division established by the plan. The results of the study illustrate the immense liberalism in the use of the analyzed instrument and marginalization of its importance in shaping urban space. The study also indicates the need for remedial actions and attempts to indicate them.

Capacity of River Valleys to Retain Nutrients from Surface Runoff in Urban and Rural Areas (Southern Poland)

Studies on water quality are necessary, as catchments of small watercourses are exposed to anthropogenic influences associated with agricultural activities, settlement, transport and other undertakings, leading to water pollution. There has been insufficient research performed on the valley’s ability to retain nutrients during floods, contributing to water accumulation. The main object of the study was to identify the retention capacity of river valleys under various aspects of human urbanization. To represent soil water retention, the Soil Conservation Service Curve Number (SCS-CN) method was used. Spatiotemporal autoregressive models were exploited to investigate the relationship between pollutants in precipitation and surface water in rivers. In contrast, multivariate analysis was used to identify and reveal patterns of land use for specific chemical compounds in the headwaters. The canonical-correlation analysis (CCA) showed that Mg+2 and Ca+2 cations in rainwater and surface waters play the main roles in the geochemical cycle in urban and rural areas. In the urban catchment area, the strongest relations were found for NO3−, K+ and Na+. The average NO3− concentration in urban headwater was 8.3 mg·dm−3, the highest in the study area. The relationship between NO3− concentration in headwater and rainwater was found for all study catchments using spatial autoregression (SAR). High concentrations of SO42− in surface water have been identified in urban areas. Severe water erosion raises the risk of nutrient leaching in soils prone to surface runoff. As a consequence of low soil permeability and urbanization, retention capacity is significantly reduced in areas with low soil permeability. Land development plans should take spatial retention capacity into consideration. To ensure that large reservoirs can retain water in the face of climate change, riparian buffer zones (protective zones in valleys for small water bodies as well as Nature-based Solution) are important.

Estimating Sediment Export and Retention Capacity of Existing Land Cover in Balanac and Sta. Cruz Watersheds, Philippines Using InVEST-SDR Model

Identifying priority areas for conservation remains a challenge since ecosystem-based models are typically data extensive. As a response to this challenge, InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) was developed to map diverse types of ecosystem services (ES). Although InVEST has been widely used in other countries, its application within the Philippines has been limited. This study offers an application of InVEST in the Philippine context. We estimated the amount of sediments exported to the streams and retained in the area by land cover type within the Balanac and Sta. Cruz watersheds. Results showed that in terms of best ecosystem service provision per hectare, vegetated areas – particularly forest land – provide the most sediment retention capacity and the least sediment export. On the other hand, the non-vegetated areas – particularly the built-up areas – provide the least sediment retention capacity and the most sediment export. These results suggest that major strategic water quality management and ES changes should be considered when converting land from one land cover type to another. Furthermore, a considerable opportunity for ecosystem service improvement to water quality through soil conservation and sustainable farming practices can be implemented in cropland areas. Since the majority of the land in both watersheds are cropland, its contribution in sediment transfers is significant, hence its role to managing soil health is of utmost importance. The findings of this study could contribute to the advancement of ES modeling in the Philippines to support land development planning and policy decisions at the national and local levels.