Mapping abandoned cropland using Within-Year Sentinel-2 time series.

Against the background of the COVID-19 pandemic and various armed conflicts, the world is experiencing an unprecedented food crisis. The reclamation of abandoned cropland with food production potential may increase the global food supply in a short period of time, ensuring food security. At present, the extraction of abandoned cropland is mainly based on low- and medium-resolution remote sensing image data, making it difficult to extract fragmented areas in mountainous regions and to distinguish between abandoned cropland and transitional classes (such as fallow cropland). We developed a change-detection method based on within-year Sentinel-2 time series to extract cropland abandoned from 2018 to 2021 and defined four types of croplands, namely spontaneously abandoned, induced abandoned, fallow, and lost cropland, using Linxia County in mountainous China as the study region. First, cropland objects were generated from multi-temporal Sentinel-2 images using the multi-resolution segmentation method, and the land use map of Linxia County from 2017 to 2021 was drawn using random forest classifier. Second, through defining and identifying different cropland types, the interannual dynamic changes in cropland from 2018 to 2021 were extracted by analyzing the annual land use change trajectory. Third, by analyzing the normalized difference vegetation index (NDVI) time series of cropland within-year, the active and cultivated cropland sites within-year were extracted by threshold segmentation. Finally, the changes in the four cropland types were extracted by intersecting the two result types. Our method captured the object level changes well (overall mapping accuracy = 93 ± 5 %), and the extraction accuracy of abandoned cropland reached 81 ± 2 %. Abandoned cropland was mostly located in areas of medium quality and with a moderate distance from rural settlements. Reclamation can potentially increase the grain production in Linxia County by at least 3.6 % and needs to be combined with the local natural geography and human activities. Our method is a robust method for extracting abandoned cropland and may be applied to other research related to land use change.

Decrypting the stream periphyton physical habitat of recently deglaciated floodplains.

The rapid recession of glaciers is exposing large zones to the development of embryonic phototrophic ecosystems and eventual ecological succession. Traditionally, succession patterns in glacial forefields have been seen as a response to time since deglaciation, but nowadays forefield exposure is so rapid that this theory may be less applicable. In this succession process, periphyton are potential pioneer organisms because of their role in modifying the local environment (e.g. access to water) to create conditions conducive to plant colonization. In this paper, we aim to decrypt the physical properties of the habitats that define the spatial and temporal assemblage of periphyton during the melt-season of an Alpine temperate glacier in the context of rapid climate change. We show that periphyton develop in glacial floodplains throughout the melt-season and could extend to cover significant surfaces. However, development is only possible when the combined conditions of stability and water accessibility are met. In glacial floodplains, stable zones exist and are typically located on terraces; but they can also be locally found for much shorter periods in the more active, glacial-stream reworked zone. On terraces, water accessibility can be a limit due to well-drained sediments, but when present, often aided by the role that biofilms play in creating an impermeable layer, it provides a stable and clear water source that biofilms could exploit. In the active part of the braid plain, whilst water availability is very high, the water is harsh (low temperature, high turbidity) and erosive. Therein, periphyton can rapidly exploit short windows of opportunity but the habitat conditions rarely remain stable for long enough for continuous periphyton cover to develop. Thus, the role of periphyton in ecosystem succession is strongly conditioned by the spatial extent of the active zone, itself a function of high rates of glacier melt and sediment supply associated with rapid glacier retreat.

Methodology for Precision Land Use Mapping towards Sustainable Urbanized Land Development.

Land-use/land cover maps constitute one of the key sources of information on urban space. To address the problems associated with the lack of timely and detailed land-use maps, the authors have developed a universal methodological approach for monitoring land use structure that is particularly useful in a rapidly evolving urban environment. Therefore, the main aim of this study was to develop a universal methodology for high-precision land-use analysis in urbanized areas in the context of large-scale mapping. The method uses geoinformation tools, photogrammetric data (orthophoto maps) as well as data acquired during a field inventory (involving a field survey and field mapping). The proposed approach is based on the modified existing approaches towards a detailed identification of land-use patterns while reducing the difficulties arising from the limitations of existing land use data sources. The methodology consists of several steps. First, the data sources for land-use analysis were selected. Subsequently, the classification of land-use categories in urban space was made. Finally, the method to high-precision land-use analysis for large-scale mapping was defined under the assumption that it is to be universal for use in countries with different levels of spatial and economic development. The proposed research method is based on an interpolation algorithm. It is highly valid, flexible, modifiable, accurate, and it can be applied to process publicly available and free sources of spatial data. Validation of the method on a test object (city of Ostróda, Poland) showed its high effectiveness, which is limited only by the type of data. The results obtained with the use of the proposed method not only supported the determination of the present land-use structure in the town but were also used to identify areas with the highest and lowest intensity and concentration of specific land-cover types.

The Impact of Accounting for Future Wood Production in Global Vertebrate Biodiversity Assessments.

Forests are among the most species rich habitats and the way they are managed influences their capacity to protect biodiversity. To fulfill increasing wood demands in the future, planted and non-planted wood production will need to expand. While biodiversity assessments usually focus on the impacts of deforestation, the effects of wood harvest are mostly not considered, especially not in a spatially explicit manner. We present here a global approach to refine the representation of forest management through allocating future wood production to planted and non-planted forests. Wood production, following wood consumption projections of three Shared Socioeconomic Pathways, was allocated using likelihood maps for planted and production forests. On a global scale, plantations for wood production were projected to increase by 45-65% and harvested area in non-planted forests by 1-17%. The biodiversity impacts of changes in wood production patterns were estimated by applying two commonly used indicators: (1) changes in species richness and (2) changes in habitat-suitable ranges of single species. The impact was analyzed using forest cover changes as reference. Our results show that, although forest cover changes have the largest impact on biodiversity, changes in wood production also have a significant effect. The magnitude of impacts caused by changes of wood production substantially differs by region and taxa. Given the importance of forest production changes in net negative emission pathways, more focus should be put on assessing the effects of future changes in wood production patterns as part of overall land use change impacts.

Physical characterization of a watershed through GIS: a study in the Schmidt stream, Brazil / Caracterização física de microbacia hidrográfica através de SIG como ferramenta de apoio a gestão: um estudo no Arroio Schmidt – RS

Remote sensing and geoprocessing are essential tools for obtaining and maintaining records of human actions on space over the course of time; these tools offer the basis for diagnoses of land use, environmental interference and local development. The Schmidt stream watershed, located in the Sinos River basin, in southern Brazil, has an environmental situation similar to that of the majority of small streams draining rural and urban areas in southern Brazil: agricultural and urbanization practices do not recognize the riparian area and there is removal of original vegetation, disregarding the suitability of land use; removal of wetlands; intensive water use for various activities; and lack of control and monitoring in the discharge of wastewater, among other factors, deteriorate the quality of this important environment.This article aims to achieve a physical characterization of the Schmidt stream watershed (Sinos river basin) identifying elements such as land use and occupation, soil science, geology, climatology, extent and location of watershed, among others, so as to serve as the basis for a tool that helps in the integrated environmental management of watersheds. By applying geographic information system - GIS to the process of obtaining maps of land use and occupation, pedologicaland geological, and using climatological data from the Campo Bom meteorological station, field visit, review of literature and journals, and publicly available data, the physical characterization of the Schmidt stream watershed was performed, with a view to the integrated environmental management of this watershed. Out of the total area of the Schmidt stream watershed (23.92 km2), in terms of geology, it was observed that 23.7% consist of colluvial deposits, 22.6% consist of grass facies, and 53.7% consist of Botucatu formation. Major soil types of the watershed: 97.4% Argisols and only 2.6% Planosols. Land use and occupation is characterized by wetland (0.5%), Native Forest (12.83%), Native Forest + Rural Anthropic + Secondary Vegetation + Forestry (43.81%), Urban Anthropic/Urban Area (39.85%), and also Urban Anthropic/Expansion areas (3.01%). Mean annual rainfall is 1337 mm, maximum temperatures range from 10.5°C to 41.6°C and minimum temperatures range from –1.80°C and 26°C, weak winds, occasionally over 5 m/s. Conducting an environmental assessment in this watershed is essential for environmental and land management. However, these assessments are not conducted in all watersheds and, when they are, their frequency is not sufficiency to allow for continuous monitoring, in order to model and predict scenarios, with a view to adopt medium and long-term measures for environmental protection.

Resumo O sensoriamento remoto e geoprocessamento de imagens se constituem em ferramentas fundamentais para a obtenção e manutenção de registros das ações humanas no espaço ao longo do tempo subsidiando diagnósticos no uso do solo, na interferência ambiental e no desenvolvimento local. A microbacia do Arroio Schmidt, localizada na bacia do Rio dos Sinos, no Rio Grande do Sul, apresenta situação ambiental semelhante a da maioria dos pequenos cursos d'agua que drenam áreas rurais e urbanas no sul do Brasil: práticas agrícolas e urbanização que não reconhecem a área ciliar com a remoção da cobertura vegetal original desrespeitando a aptidão do uso dos solos, remoção de áreas úmidas, uso intenso da água para diversas atividades e falta de controle e monitoramento no lançamento de efluentes entre outros, deterioram a qualidade deste importante ambiente. O objetivo deste trabalho é a caracterização física da Microbacia do Arroio Schmidt (Bacia do Rio dos Sinos) identificando elementos como uso e ocupação do solo, pedologia, geologia, climatologia, extensão e localização da Microbacia entre outros, a fim de instrumentalizar uma ferramenta auxiliar de gestão ambiental integrada de bacias hidrográficas. Através da aplicação do geoprocessamento no processo de obtenção dos mapas de uso e ocupação do solo, pedológico e geológico e uso de dados climatológicos da estação climatológica de Campo Bom-RS, visita a campo, revisão bibliográfica e de periódicos, dados públicos disponíveis, foi realizada a caracterização física da microbacia hidrográfica do Arroio Schmidt, visando a gestão ambiental integrada desta microbacia. Da área total da microbacia hidrográfica do Arroio Schmidt (23,92 km2) observou-se quanto à geologia que 23,7% são Colúvios, Fácies Gramado 22,6% e Formação Botucatu 53,7%. Principais tipos de solos da microbacia: Argissolos 97,4% e os Planossolos que ocupam apenas 2,6%. O uso e ocupação do solo é caracterizado por área úmida (0,5%), Mata Nativa (12,83%), Mata Nativa + Antrópico Rural + Vegetação Secundária + Silvicultura (43,81%), Antrópico Urbano/Área Urbana (39,85%) e ainda Antrópico Urbano/Áreas de expansão (3,01%). Precipitação média anual de 1337 mm, temperaturas máximas entre 10,5°C e 41,6°C e as mínimas entre –1,8°C e 26°C, Ventos fracos, eventualmente passam de 5 m/s. A realização da avaliação ambiental nesta microbacia é fundamental na gestão ambiental e territorial. No entanto, estas avaliações não ocorrem em todas as microbacias e, quando ocorrem, não apresentam a frequência adequada para permitir o monitoramento contínuo a fim de modelar e prever cenários objetivando a adoção de medidas de médio e longo prazo para a proteção ambiental.

Physical characterization of a watershed through GIS: a study in the Schmidt stream, Brazil

Remote sensing and geoprocessing are essential tools for obtaining and maintaining records of human actions on space over the course of time; these tools offer the basis for diagnoses of land use, environmental interference and local development. The Schmidt stream watershed, located in the Sinos River basin, in southern Brazil, has an environmental situation similar to that of the majority of small streams draining rural and urban areas in southern Brazil: agricultural and urbanization practices do not recognize the riparian area and there is removal of original vegetation, disregarding the suitability of land use; removal of wetlands; intensive water use for various activities; and lack of control and monitoring in the discharge of wastewater, among other factors, deteriorate the quality of this important environment.This article aims to achieve a physical characterization of the Schmidt stream watershed (Sinos river basin) identifying elements such as land use and occupation, soil science, geology, climatology, extent and location of watershed, among others, so as to serve as the basis for a tool that helps in the integrated environmental management of watersheds. By applying geographic information system - GIS to the process of obtaining maps of land use and occupation, pedologicaland geological, and using climatological data from the Campo Bom meteorological station, field visit, review of literature and journals, and publicly available data, the physical characterization of the Schmidt stream watershed was performed, with a view to the integrated environmental management of this watershed. Out of the total area of the Schmidt stream watershed (23.92 km2), in terms of geology, it was observed that 23.7% consist of colluvial deposits, 22.6% consist of grass facies, and 53.7% consist of Botucatu formation. Major soil types of the watershed: 97.4% Argisols and only 2.6% Planosols. Land use and occupation is characterized by wetland (0.5%), Native Forest (12.83%), Native Forest + Rural Anthropic + Secondary Vegetation + Forestry (43.81%), Urban Anthropic/Urban Area (39.85%), and also Urban Anthropic/Expansion areas (3.01%). Mean annual rainfall is 1337 mm, maximum temperatures range from 10.5°C to 41.6°C and minimum temperatures range from 1.80°C and 26°C, weak winds, occasionally over 5 m/s. Conducting an environmental assessment in this watershed is essential for environmental and land management. However, these assessments are not conducted in all watersheds and, when they are, their frequency is not sufficiency to allow for continuous monitoring, in order to model and predict scenarios, with a view to adopt medium and long-term measures for environmental protection.

Resumo O sensoriamento remoto e geoprocessamento de imagens se constituem em ferramentas fundamentais para a obtenção e manutenção de registros das ações humanas no espaço ao longo do tempo subsidiando diagnósticos no uso do solo, na interferência ambiental e no desenvolvimento local. A microbacia do Arroio Schmidt, localizada na bacia do Rio dos Sinos, no Rio Grande do Sul, apresenta situação ambiental semelhante a da maioria dos pequenos cursos d'agua que drenam áreas rurais e urbanas no sul do Brasil: práticas agrícolas e urbanização que não reconhecem a área ciliar com a remoção da cobertura vegetal original desrespeitando a aptidão do uso dos solos, remoção de áreas úmidas, uso intenso da água para diversas atividades e falta de controle e monitoramento no lançamento de efluentes entre outros, deterioram a qualidade deste importante ambiente. O objetivo deste trabalho é a caracterização física da Microbacia do Arroio Schmidt (Bacia do Rio dos Sinos) identificando elementos como uso e ocupação do solo, pedologia, geologia, climatologia, extensão e localização da Microbacia entre outros, a fim de instrumentalizar uma ferramenta auxiliar de gestão ambiental integrada de bacias hidrográficas. Através da aplicação do geoprocessamento no processo de obtenção dos mapas de uso e ocupação do solo, pedológico e geológico e uso de dados climatológicos da estação climatológica de Campo Bom-RS, visita a campo, revisão bibliográfica e de periódicos, dados públicos disponíveis, foi realizada a caracterização física da microbacia hidrográfica do Arroio Schmidt, visando a gestão ambiental integrada desta microbacia. Da área total da microbacia hidrográfica do Arroio Schmidt (23,92 km2) observou-se quanto à geologia que 23,7% são Colúvios, Fácies Gramado 22,6% e Formação Botucatu 53,7%. Principais tipos de solos da microbacia: Argissolos 97,4% e os Planossolos que ocupam apenas 2,6%. O uso e ocupação do solo é caracterizado por área úmida (0,5%), Mata Nativa (12,83%), Mata Nativa + Antrópico Rural + Vegetação Secundária + Silvicultura (43,81%), Antrópico Urbano/Área Urbana (39,85%) e ainda Antrópico Urbano/Áreas de expansão (3,01%). Precipitação média anual de 1337 mm, temperaturas máximas entre 10,5°C e 41,6°C e as mínimas entre 1,8°C e 26°C, Ventos fracos, eventualmente passam de 5 m/s. A realização da avaliação ambiental nesta microbacia é fundamental na gestão ambiental e territorial. No entanto, estas avaliações não ocorrem em todas as microbacias e, quando ocorrem, não apresentam a frequência adequada para permitir o monitoramento contínuo a fim de modelar e prever cenários objetivando a adoção de medidas de médio e longo prazo para a proteção ambiental.