Silt-sized sediments and gypsum on surface formations in the Ebro valley. A disambiguation of the term gypsiferous silts

Since the 60’s, many authors have reported the presence of common silt-sized materials in the Ebro valley, on surface formations and positions that have given rise to several interpretations, sometimes contradictory. According to the references, three main terms are used (gypsiferous silts, loess and flour-like gypsum) applied to silts and fine sands with gypsum accumulations. The two first terms are applied to materials with carbonate contents up to 40-50%, coarse silty to fine sandy textures, and located in different positions. Loess normally appears as thick outcrops on slopes leeward from the main wind direction, with a limited pedogenesis consisting of a partial carbonate mobilisation and gypsum contents between 0 and 30%. The third (gypsum-rich) type has a variable spatial distribution, appearing between limestone layers, along footslopes, outcropping as metric surface formations, or as generalized karstified subsurface accumulations. Their composition is almost 100% silt- to fine sand size lenticular gypsum. While some authors claim for an aeolian origin to all these materials, only part of them (loess) has a clear aeolian origin, while flour-like gypsum derives from on-site weathering of gyprock or by precipitation of calcium- and sulfate saturated watertables as it is reported to occur in many other arid regions; and the rest (gypsiferous silts sensu stricto) are mainly colluvial-alluvial. This distinction is necessary since they differ in their geotechnical behaviour and properties relevant for agricultural land uses, therefore they should be taken into account when carrying out geological mappings or soil surveys in this and similar arid regions.

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Effects of Different Land Uses and Cultivation Periods on Spatial Distribution of Soil Nutrients in Karst Mountainous Region*

Chinese Journal of Appplied Environmental Biology ◽

10.3724/sp.j.1145.2011.00063 ◽

2011 ◽

Vol 17 (1) ◽

pp. 63-68 ◽

Cited By ~ 1

Author(s):

Chuanyan ZHOU ◽

Xun CHEN ◽

Guoyi ZHOU ◽

Junhua YAN

Keyword(s):

Spatial Distribution ◽

Soil Nutrients ◽

Mountainous Region ◽

Land Uses

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Modelling Agricultural Controls for Flooding and Soil Erosion

The Oxford Handbook of Food, Water and Society ◽

10.1093/oxfordhb/9780190669799.013.56 ◽

2018 ◽

pp. 776-796

Author(s):

Roger Moussa ◽

Bruno Cheviron

Keyword(s):

Spatial Distribution ◽

Model Structure ◽

Land Uses ◽

Research Challenges ◽

Water And Sediment ◽

Flow Processes ◽

Cultivation Practices ◽

Modelling Strategies ◽

The Impact ◽

Significant Factors

Floods are the highest-impact natural disasters. In agricultural basins, anthropogenic features are significant factors in controlling flood and erosion. A hydrological-hydraulic-erosion diagnosis is necessary in order to choose the most relevant action zones and to make recommendations for alternative land uses and cultivation practices in order to control and reduce floods and erosion. This chapter first aims to provide an overview of the flow processes represented in the various possible choices of model structure and refinement. It then focuses on the impact of the spatial distribution and temporal variation of hydrological soil properties in farmed basins, representing their effects on the modelled water and sediment flows. Research challenges and leads are then tackled, trying to identify the conditions in which sufficient adequacy exists between site data and modelling strategies.

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Changes in Coastal Agricultural Land Use in Response to Climate Change: An Assessment Using Satellite Remote Sensing and Household Survey Data in Tien Hai District, Thai Binh Province, Vietnam

Land ◽

10.3390/land10060627 ◽

2021 ◽

Vol 10 (6) ◽

pp. 627

Author(s):

Duong H. Nong ◽

An T. Ngo ◽

Hoa P. T. Nguyen ◽

Thuy T. Nguyen ◽

Lan T. Nguyen ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

Agricultural Land ◽

Land Use Changes ◽

Management Strategies ◽

Household Survey ◽

Extreme Weather Events ◽

Agricultural Land Use ◽

Landsat 8 ◽

Land Uses

We analyzed the agricultural land-use changes in the coastal areas of Tien Hai district, Thai Binh province, in 2005, 2010, 2015, and 2020, using Landsat 5 and Landsat 8 data. We used the object-oriented classification method with the maximum likelihood algorithm to classify six types of land uses. The series of land-use maps we produced had an overall accuracy of more than 80%. We then conducted a spatial analysis of the 5-year land-use change using ArcGIS software. In addition, we surveyed 150 farm households using a structured questionnaire regarding the impacts of climate change on agricultural productivity and land uses, as well as farmers’ adaptation and responses. The results showed that from 2005 to 2020, cropland decreased, while aquaculture land and forest land increased. We observed that the most remarkable decreases were in the area of rice (485.58 ha), the area of perennial crops (109.7 ha), and the area of non-agricultural land (747.35 ha). The area of land used for aquaculture and forest increased by 566.88 ha and 772.60 ha, respectively. We found that the manifestations of climate change, such as extreme weather events, saltwater intrusion, drought, and floods, have had a profound impact on agricultural production and land uses in the district, especially for annual crops and aquaculture. The results provide useful information for state authorities to design land-management strategies and solutions that are economic and effective in adapting to climate change.

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Spatial Distribution and Evaluation of Arsenic and Zinc Content in the Soil of a Karst Landscape

Sustainability ◽

10.3390/su13126976 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6976

Author(s):

Dimitrios E. Alexakis ◽

George D. Bathrellos ◽

Hariklia D. Skilodimou ◽

Dimitra E. Gamvroula

Keyword(s):

Land Use ◽

Spatial Distribution ◽

Land Use Planning ◽

Urban Soil ◽

Agricultural Soil ◽

Agricultural Land ◽

Land Evaluation ◽

Agricultural Activity ◽

North West ◽

Total Study Area

Karst features such as polje are highly vulnerable to natural and anthropogenic pollution. The main objectives of this study were to investigate the soil quality in the Ioannina polje (north-west Greece) concerning arsenic (As) and zinc (Zn), and delineate their origin as well as compare the As and Zn content in soil with criteria recorded in the literature. For this purpose, the geomorphological settings, the land use, and the soil physicochemical properties were mapped and evaluated, including soil texture and concentrations of aqua-regia extractable As and Zn. The concentration of elements was spatially correlated with the land use and the geology of the study area, while screening values were applied to assess land suitability. The results reveal that 72% of the total study area has a very gentle slope. This relief favors urban and agricultural activity. Thus, the urban and agricultural land used cover 92% of the total area. The spatial distribution for As and Zn in the soil of the study area is located on very gentle slopes and is strongly correlated with the geological parent materials and human-induced contamination sources. Arsenic and Zn can be considered enriched in the soil of the area studied. The median topsoil contents (in mg kg−1) for As (agricultural soil 16.0; urban soil 17.8) and Zn (agricultural soil 92.0; urban soil 95.0) are higher compared to the corresponding median values of European topsoils. Land evaluation suitability concerning criteria given from the literature is discussed. The proposed work may be helpful in the project of land use planning and the protection of the natural environment.

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The Long and Winding Boundaries: Quantifying Interfaces Between Residential, Natural and Agricultural Land Uses

SSRN Electronic Journal ◽

10.2139/ssrn.3868428 ◽

2020 ◽

Author(s):

Dani Broitman

Keyword(s):

Agricultural Land ◽

Land Uses

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Conversion of farmland to non-agricultural land uses in peri-urban areas of Addis Ababa Metropolitan city, Central Ethiopia

GeoJournal ◽

10.1007/s10708-021-10553-9 ◽

2022 ◽

Author(s):

Duguma Erasu Tufa ◽

Tebarek Lika Megento

Keyword(s):

Urban Areas ◽

Agricultural Land ◽

Addis Ababa ◽

Land Uses ◽

Central Ethiopia ◽

Metropolitan City

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Brief Communication: Future avenues for permafrost science from the perspective of early career researchers

The Cryosphere ◽

10.5194/tc-9-1715-2015 ◽

2015 ◽

Vol 9 (4) ◽

pp. 1715-1720 ◽

Cited By ~ 16

Author(s):

M. Fritz ◽

B. N. Deshpande ◽

F. Bouchard ◽

E. Högström ◽

J. Malenfant-Lepage ◽

...

Keyword(s):

Climate Change ◽

Spatial Distribution ◽

Traditional Knowledge ◽

Landscape Dynamics ◽

Early Career ◽

Research Topics ◽

The Third ◽

Early Career Researchers ◽

Integrated Research ◽

Environmental Interests

Abstract. Accelerating climate change and increased economic and environmental interests in permafrost-affected regions have resulted in an acute need for more directed permafrost research. In June 2014, 88 early career researchers convened to identify future priorities for permafrost research. This multidisciplinary forum concluded that five research topics deserve greatest attention: permafrost landscape dynamics, permafrost thermal modeling, integration of traditional knowledge, spatial distribution of ground ice, and engineering issues. These topics underline the need for integrated research across a spectrum of permafrost-related domains and constitute a contribution to the Third International Conference on Arctic Research Planning (ICARP III).

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