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One of the limitations of satellite techniques in archaeological investigations is the land cover. Heritage objects may be more or less visible depending on the land cover type. Low vegetation, such as grass or small shrubs, will usually allow us to determine the location of archaeological objects if the difference in height between the object and vegetation is not significant enough. Forest or high vegetation cover makes it more challenging to determine the location of potentially artificial structures. This project's study area covered 50×70 km of the lower reaches of the Vistula River, Poland. The authors searched for anthropogenic objects close to watercourses and analysed nine different (point, line and surface type) objects having a defensive, sepulchral or settlement function. Circular objects, ditches and earth embankments, burial mounds and strongholds of regular forms were found during this research. Based on nine different models processed with LiDAR-based DEMs, several characteristics and relationships of various types of objects were demonstrated. Moreover, optimal models for searching for archaeological objects in forest areas were defined. [ABSTRACT FROM AUTHOR]

Landscape archaeology (archaeogeography) is a multidisciplinary study used by prehistorical, classic, and historical archaeologists. Archaeogeography deals with the study of how people have shaped and used their environment throughout history. It focuses on the relationship between the material culture of a given community and the changes it introduces in its spatial environment. Traditionally search for archaeological sites is mainly carried out using surface research, i.e., observation of ploughed fields in spring and autumn. However, the percentage ratio of the area covered by forests to the total area of the countries can reach up to even several dozen per cent. This is where archaeogeography aided with modern remote sensing data and processing techniques can be most useful. In this article, the authors describe the problems occurring while searching for anthropological objects in forest areas. In this first part of the two-part series, the authors present a non-invasive method based on widely available remote sensing and historical data that can be used for remote prospection or archaeological sides. The authors also present methods of field verification and critically describe the limitations and advantages of this method. [ABSTRACT FROM AUTHOR]

Eco-environmental change prediction models are important decision tools for policy makers, as they help to quantify environmental sensitivity and to understand the relationship between human activities and environmental quality. Thus, this paper aims to analyze eco-environmental changes in Monteiro County, a semi-arid zone within northeastern Brazil between 1987 and 2010, by means of satellite images, geographic information system and global positioning system techniques, topographic map, climatic data and soil maps, as well as field survey. The resulting outputs were evaluated for their ability to accurately predict the most sensitive and least sensitive areas. The results showed that land cover changes have modified the environment in general and the land degradation and low soil loss processes were identified. The mean soil loss decreased from 9.67 t ha-1 yr-1 in 1987 to 2.67 t ha-1 yr-1 in 2010, as an effect of vegetation gain and particularly the conversion of thousands of square kilometers of Tropophile caatinga middle slope and barren land into Tropophile caatinga plain and Tropophile caatinga high strand. Thus, this study provides insight on territorial ordering and management of environmental services with a regional perspective. [ABSTRACT FROM AUTHOR]

In this application-based study, the influence of the catchment discretization on the optimization of runoff-erosion modeling using a particle swarm optimization to a physically-based erosion model named WESP (Watershed Erosion Simulation Program) is conducted. This study is carried in the semiarid region of Brazil, more precisely in a micro-catchment (MCN3) of Sumé Experimental Basin. A comparative assessment is done by statistical analysis and mean relative error (MRE) in order to evaluate the performance of the optimization technique when discretizing the catchment in different ways. Thus, the catchment is represented in three ways of discretization (i.e., n1 = 4 elements, n2 = 10 elements and n3 = 23 elements). The difficulties involved in calibration of physically-based erosion models have been partly attributable to the lack of robust optimization tools, hence several robust optimization techniques have been proposed in the past years; however, the way the catchment is represented could interfere on the results. Thus, this paper presents the essential concepts of the runoff-erosion WESP model, the global optimization method known as Repulsive Particle Swarm (RPS), and the optimization results using the three catchment discretization. The results show that there are small differences among the calculated sediment yield using the three ways of basin discretization, although the 23 elements division seems to give the best results. [ABSTRACT FROM AUTHOR]

The increase of house condominiums in the Brazilian cities is gradually increasing due to problems concerning traffic tie-up, air pollution level, amongst others. In these condominiums, large green areas for leisure, comfort and better life quality for the joint owners are reserved. The large house gardens need hard maintenance, which raises the water demand in the condominiums. The use of the rainwater is an alternative that could be used in Brazil and other countries to minimize the use of potable water in nonpotable water needs, such as car wash, garden irrigation, etc. This paper evaluates the precipitation in João Pessoa city (capital of Paraíba state, Brazil), according to the frequency analysis and significance test. Thus, it was applied a robust tool to analyze signal frequency, named wavelet transform, which is appropriated to analyze irregular events and non-stationary series. It was analyzed two precipitation series of João Pessoa city, 1937-1970 and 1980-1996, when it was observed a significant annual signal at level 10%, which revealed the existence of an annual rainy season, which is very convenient for the water storage for further using during the dry season. Finally, the reservoir is an important item in the rainwater system and it has to be correctly design in order to make the system economically practicable. The Rippl method was used for the reservoir sizing analysis. [ABSTRACT FROM AUTHOR]

The spatio-temporal assessment of water and carbon fluxes in Brazil's Northeast region (NEB) allows for a better understanding of these surface flux patterns in areas with different vegetation physiognomies. The NEB is divided into four biomes: Amazon, Cerrado, Caatinga, and Atlantic Forest. Land degradation is a growing problem, particularly in susceptible areas of the Caatinga biome, such as the seasonally dry tropical forest. Furthermore, this region has experienced climatic impacts, such as severe droughts. Due to increasing human pressure, the Caatinga's natural land cover undergoes drastic changes, making it a region particularly vulnerable to desertification. In this study, the Moderate Resolution Imaging Spectroradiometer (MODIS) estimates of evapotranspiration (ET) and gross primary production (GPP) were validated in two contrasting areas, dense Caatinga and sparse Caatinga, using eddy covariance (EC) data and then investigated their behavior over 21 years (2000-2021) for the NEB. MODIS products explained around 60% of the variations in ET and GPP, showing higher accuracy in dense Caatinga, while areas of sparse Caatinga presented the lowest GPP, indicating that land degradation has reduced the photosynthetic activity of the vegetation in this area. Based on the analysis of ET and GPP over 21 years, we observed a greater dependence of the sparse Caatinga on climate variability, demonstrating a stronger resilience of dense Caatinga to climate effects. In comparison with the other biomes of the NEB region, we found lower rates of ET and GPP in the Caatinga biome, with averages similar to the Sparse Caatinga. In comparison with the other biomes in the NEB region, we found the lowest averages of ET and GPP in the Caatinga biome, similar to values found in the sparse Caatinga. In forest areas, similar to the monitored DC, they allowed the Caatinga to behave closer to the other biomes present in the region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The Brazilian semiarid region presents a physical water scarcity and high seasonal and interannual irregularities of precipitation, known as a region with periodic droughts. This region is mainly covered by the Caatinga biome, recognized as a Seasonally Dry Tropical Forest (SDTF). Soil water availability directly impacts the ecosystem's functioning, characterized by low fertility and sparse vegetation cover during the dry season, making it a fragile ecosystem vulnerable to climatic variations. Additionally, this region has been suffering from several issues due to human activities over the centuries, which has resulted in extensive areas being severely degraded, which aggravates the impacts from climatic variations and the susceptibility to desertification. Thus, studying the soil-plant-atmosphere continuum in this region can help better understand the seasonal and annual behavior of the water and carbon fluxes. This study investigated the dynamics of water and carbon fluxes during four years (2013-2016) by using eddy covariance (EC) measurements within two areas of Caatinga (dense Caatinga (DC) and sparse Caatinga (SC)) that suffered anthropic pressures. The two study areas showed similar behavior in relation to physical parameters (air temperature, incoming radiation, vapor pressure deficit, and relative humidity), except for soil temperature. The SC area presented a surface temperature of 3 °C higher than the DC, related to their vegetation cover differences. The SC area had higher annual evapotranspiration, representing 74% of the precipitation for the DC area and 90% for the SC area. The two areas acted as a carbon sink during the study period, with the SC area showing a lower CO 2 absorption capacity. On average, the DC area absorbs 2.5 times more carbon than the SC area, indicating that Caatinga deforestation affects evaporative fluxes, reducing atmospheric carbon fixation and influencing the ability to mitigate the effects of increased greenhouse gas concentrations in the atmosphere., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)