Variação de atributos do solo ao longo de três topossequências no planalto do Rio Grande do Sul (Variation of soil attribute along of three toposequence in the Rio Grande do Sul plateau)

Este trabalho investigou os efeitos da topografia e das práticas de uso e manejo do solo na variabilidade de alguns atributos do solo ao longo de três topossequências localizadas no planalto do Rio Grande do Sul. As topossequências (Tps) estão inseridas em uma bacia hidrográfica situada no município de Júlio de Castilhos. Na Tp1 foram definidos quatro pontos de amostragem e na Tp2 e Tp3, cinco pontos. Em cada perfil foram coletadas amostras em 5 camadas de solo (0‒5, 5‒10, 10‒20, 20‒40 e 40‒60 cm). Em laboratório foram determinados os atributos: densidade, argila, pH em água, carbono (C) orgânico total, fósforo (P) total, P orgânico total, P disponível, óxidos de ferro (Fe) e alumínio (Al) cristalinos e amorfos. Os resultados encontrados mostram que o movimento de sedimentos em superfície e através do perfil do solo é controlado pela posição, forma e declividade da encosta e, pelas atividades antrópicas como o uso e manejo do solo e aplicação de fertilizantes. Considerando as classes de uso da terra, os maiores teores de C e P (total, orgânico e disponível) foram obtidos na área úmida, seguido da lavoura e campo nativo. Considerando a posição na encosta os teores de C e P foram maiores na baixada seguido da base da encosta, topo e meia encosta. A condição hidromórfica ao longo das topossequências desempenhou um papel importante na disponibilidade de P, acúmulo C orgânico total e solubilização dos óxidos de Fe e Al. A B ST R A C TThis work investigated the effects of topography and land use and soil management practices on the variability of some soil properties along three toposequences located in the Rio Grande do Sul plateau, Southern Brazil. The toposequences (Tps) evaluated are from a watershed located in the municipality of Júlio de Castilhos. Soil samples were taken in four points in Tp1 and in five points in Tp2 and Tp3. In each point samples were taken at five depths (0‒5, 5‒10, 10‒20, 20‒40, and 40‒60 cm). The soil properties evaluated were soil density, clay, pH in water, total organic carbon (C), total phosphorus (P), total organic P, available P, and amorphous and crystalline iron (Fe) and aluminum (Al) oxides. Results show that the transport of sediments on the surface and through the soil profile is controlled by topographic position, landform, slope, and also by the anthropic activities such as the use and management of the soil and the application of fertilizers. Considering the classes of land use, the highest levels of C and P (total, organic and available) were obtained in the wetlands, followed by the crop fields and natural grasslands. Considering the topographic position, the contents of C and P were higher in the floodplain followed by the base of the slope, top and middle slope. Hydromorphic conditions along the toposequences played an important role in P availability, total organic C accumulation and solubilization of Fe and Al oxides.keywords: Land use, topographic position, soil profile, soil properties.

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Temporal dynamics of land use and cover in Paurá Lagoon region, Middle Coast of Rio Grande do Sul (RS), Brazil

Revista de Gestão Costeira Integrada ◽

10.5894/rgci-n106 ◽

2018 ◽

Vol 18 (1) ◽

pp. 25-39

Author(s):

Katia Helena Lipp-Nissinen ◽

Bruna de Sá Piñeiro ◽

Letícia Sebastião Miranda ◽

Alexandre de Paula Alves

Keyword(s):

Land Use ◽

Temporal Dynamics ◽

Rio Grande ◽

Rio Grande Do Sul ◽

Land Use And Cover

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Phosphorus fractionation in grasses with different resource-acquisition characteristics in natural grasslands of South America

Journal of Tropical Ecology ◽

10.1017/s0266467419000166 ◽

2019 ◽

Vol 35 (5) ◽

pp. 203-212 ◽

Cited By ~ 1

Author(s):

Anderson Cesar Ramos Marques ◽

Rogério Piccin ◽

Tales Tiecher ◽

Leandro Bittencourt de Oliveira ◽

João Kaminski ◽

...

Keyword(s):

South America ◽

Phosphorus Fractionation ◽

Paspalum Notatum ◽

Chemical Fractionation ◽

P Availability ◽

Inorganic P ◽

Nutrient Demand ◽

Natural Grasslands ◽

Low Phosphorus ◽

Total P

AbstractThe natural grasslands in South America have soils with low phosphorus (P) availability (1.0 to 7.5 mg kg−1), possibly altering the absorption and accumulation of P in grasses. We evaluated the chemical fractionation of P in the leaves of the most important grasses present in these grasslands to better understand the mechanisms involved in the storage of P. The grasses studied were Axonopus affinis and Paspalum notatum (fast tissue cycling and high nutrient demand) and Andropogon lateralis and Aristida laevis (slow tissue cycling and low nutrient demand). They were grown in pots filled with an Ultisol with two levels of P: control, and addition of 50 mg P kg–1. The main P fractions were the inorganic soluble (44%) and P in RNA (26%). Addition of P increased the total P concentration, following the order A. affinis (140%) > P. notatum (116%) > A. lateralis (81%) > A. laevis (21%). In conclusion, the species A. affinis and P. notatum responded to P fertilization with high variation and accumulating P in less-structural chemical forms, such as inorganic P. The species A. lateralis and A. laevis showed low variation in the concentration of P forms, with higher P concentrations in structural forms.

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Alterações dos nutrientes no solo e nas plantas em consórcio de eucalipto e acácia negra

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832001000100024 ◽

2001 ◽

Vol 25 (1) ◽

pp. 225-231 ◽

Cited By ~ 20

Author(s):

F. M. Vezzani ◽

M. J. Tedesco ◽

N. F. Barros

Keyword(s):

Rio Grande ◽

Rio Grande Do Sul ◽

Acacia Mearnsii ◽

Eucalyptus Saligna ◽

Total P

O consórcio de eucalipto e acácia negra pode trazer benefícios ecológicos e econômicos, tendo em vista a diversidade ambiental e redução dos custos com adubação nitrogenada. Este trabalho teve o objetivo de quantificar os nutrientes no solo e nas plantas e avaliar o crescimento e a produção de eucalipto em consórcio com acácia negra. Foram estudados sistemas de cultivo simples e consorciado de Eucalyptus saligna (Smith) e Acacia mearnsii (De Wild.), com 45 meses de idade, em Argissolo Vermelho-Amarelo, no estado do Rio Grande do Sul. O espaçamento foi de 4,0 x 1,5 m e, no consórcio, as espécies foram plantadas em fileiras alternadas. Quantificaram-se N total, P, K, Ca, Mg, Al e matéria orgânica no solo e N total, P, K, Ca e Mg nas plantas. Avaliaram-se altura e diâmetro das árvores, bem como o volume de madeira produzido. As amostras de solo foram coletadas nas profundidades de 0-5, 5-10, 10-20 e 20-40 cm. Os resultados demonstraram maior teor de matéria orgânica e nitrogênio total no solo do consórcio em relação ao eucalipto simples. Solo sob cultivo simples de acácia mostrou maior teor de K, Ca e Mg que nos povoamentos em que o eucalipto estava presente. Plantas de eucalipto consorciado absorveram mais nitrogênio (22%) do que as do cultivo simples. O volume total de madeira no consórcio não diferiu do cultivo simples de eucalipto, embora o eucalipto tenha contribuído com 64% da produção do consórcio. O consórcio beneficiou a nutrição de nitrogênio do eucalipto e aumentou o estoque de nitrogênio no ecossistema, enquanto manteve a produção total de madeira.

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Soil management in Brazilian states: comparative analyzes of Physical and Monetary Soil Nutrient Balance in 2005 and 2015

Revista Agro mbiente On-line ◽

10.18227/1982-8470ragro.v14i0.6193 ◽

2020 ◽

Vol 14 ◽

Author(s):

Wladimir Colman De Azevedo Junior ◽

Marcos Rodrigues

Keyword(s):

Land Use ◽

Agricultural Production ◽

Nutrient Balance ◽

Soil Nutrient ◽

Soil Management ◽

Rio Grande ◽

Rio Grande Do Sul ◽

Biological Fixation ◽

Mato Grosso ◽

Annual Balance

Intensive agricultural production tends to stimulate the outflow of nutrients from the soil, requiring producers to properly manage the soil to avoid reducing fertility in the following crops. Thus, the objective was to estimate the annual monetary balance of nutrients in the soil of six Brazilian states that present the highest consumption of inorganic fertilizers in the years 2005 and 2015. The Annual Balance of Nutrients in Soil was used to calculate the physical and monetary balance of nutrients, in the main crops of these States, by quantifying the export of N, P, K from the soil by plants and the insertion of nutrients, through the application of fertilizers, fertigation, and biological fixation. The monetary balance of N, P and K added for the six states was positive and increased by 114% between 2005 and 2015, however, the balance of P for the state of Paraná was negative in 2015 reaching R$ 1,769.17. The balances and Mato Grosso, Rio Grande do Sul, and Paraná were higher concerning Goiás, São Paulo, and Minas Gerais. Except for Paraná, related to P, there was no positive depreciation of the associated NPK nutrients. The different flows, in the comparison among states, are caused by the different dynamics of land use, mainly in the size of the corn and soybean cultivation area.

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Changes in Soil Organic Carbon and Its Labile Fractions after Land Conversion from Paddy Fields to Woodlands or Corn Fields

Agronomy ◽

10.3390/agronomy12010029 ◽

2021 ◽

Vol 12 (1) ◽

pp. 29

Author(s):

Linlin Si ◽

Wenhai Mi ◽

Yan Sun ◽

Wanghai Tao ◽

Jihong Zhang ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Soil Profile ◽

Soil Layer ◽

Paddy Fields ◽

Organic C ◽

Field Soils ◽

Labile C ◽

Labile C Fractions ◽

Corn Fields

Land use change could significantly affect soil organic carbon (SOC) and other soil chemical properties. However, the responses of soil labile C fractions at different soil depths to land-use change are not still clear. The aim of this study was to investigate the effect of paddy field conversion on woodlands or corn fields on total soil organic C (TOC) and its labile C fractions including particulate organic C (POC), microbial biomass C (MBC), and potassium permanganate-oxidizable C (KMnO4–C) along a 0–100 cm soil profile. Our results indicate that soil TOC concentrations increased by 3.88 g kg−1 and 3.47 g kg−1 in the 0–5 cm soil layer and 5.33 g kg−1 and 4.68 g kg−1 in the 5–20 cm soil layer during 13 years after the conversion from paddy fields to woodlands and corn fields, respectively. In the 20–40 cm soil layer, the woodlands had the highest TOC concentration (12.3 g kg−1), which was 5.13 g kg−1 and 3.5 g kg−1 higher than that of the paddy and corn fields, respectively. The increase in TOC was probably due to the absence of soil disturbance and greater root residue input into the woodland soil. In corn fields, pig manure addition contributed to the increase in soil organic C concentrations. In addition, the proportion of soil KMnO4–C increased after conversion from paddy fields to woodlands or corn fields in the 0–40 cm soil layer, ranging from 39.9–56.6% for the woodlands and 24.6–32.9% for the corn fields. The soil POC content was significantly higher in woodland and corn field soils than in paddy field soils at lower soil depths (5–40 cm). However, there were no differences in MBC contents in the whole soil profile between the woodlands and paddy fields. The KMnO4–C and MBC was the most important factor affecting the CMI values through the whole 0–100 cm soil profile. Overall, converting paddy fields to woodlands or corn fields increased the TOC and labile C fractions in the 0–40 cm soil layer. Future studies should focus on the response of the deeper soil C pool to land-use change.

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Evaluation of Physicochemical Properties of Sandy-Textured Soils under Smallholder Agricultural Land Use Practices in Sarawak, East Malaysia

Applied and Environmental Soil Science ◽

10.1155/2019/7685451 ◽

2019 ◽

Vol 2019 ◽

pp. 1-14

Author(s):

Soo Ying Ho ◽

Mohd Effendi Bin Wasli ◽

Mugunthan Perumal

Keyword(s):

Land Use ◽

Physicochemical Properties ◽

Soil Properties ◽

Oil Palm ◽

Agricultural Land ◽

Secondary Forests ◽

Land Uses ◽

Total N ◽

Organic C ◽

Nutrient Contents

A study was conducted in the Sabal area, Sarawak, to evaluate the physicochemical properties of sandy-textured soils under smallholder agricultural land uses. Study sites were established under rubber, oil palm, and pepper land uses, in comparison to the adjacent secondary forests. The sandy-textured soils underlain in all agricultural land uses are of Spodosols, based on USDA Soil Taxonomy. The soil properties under secondary forests were strongly acidic with poor nutrient contents. Despite higher bulk density in oil palm farmlands, soil properties in rubber and oil palm land uses showed little variation to those in secondary forests. Conversely, soils under pepper land uses were less acidic with higher nutrient contents at the surface layer, especially P. In addition, soils in the pepper land uses were more compact due to human trampling effects from regular farm works at a localized area. Positive correlations were observed between soil total C and soil total N, soil exchangeable K, soil sum of bases, and soil effective CEC, suggesting that soil total C is the determinant of soil fertility under the agricultural land uses. Meanwhile, insufficient K input in oil palm land uses was observed from the partial nutrient balances estimation. In contrast, P and K did not remain in the soils under pepper land use, although the fertilizers application by the farmers was beyond the crop uptake and removal (harvesting). Because of the siliceous sandy nature (low clay contents) of Spodosols, they are poor in nutrient retention capacity. Hence, maintaining ample supply of organic C is crucial to sustain the productivity and fertility of sandy-textured soils, especially when the litterfall layers covering the E horizon were removed for oil palm and pepper cultivation.

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Methane production potential of soil profile in organic paddy field

Soil and Water Research ◽

10.17221/58/2016-swr ◽

2017 ◽

Vol 12 (No. 4) ◽

pp. 212-219 ◽

Cited By ~ 1

Author(s):

M. Mujiyo ◽

B.H. Sunarminto ◽

E. Hanudin ◽

J. Widada ◽

J. Syamsiyah

Keyword(s):

Soil Properties ◽

Soil Profile ◽

Rice Field ◽

Farming Systems ◽

Rice Fields ◽

Maximum Point ◽

Production Potential ◽

Organic C ◽

Mitigation Options ◽

Organic Rice

The use of organic fertilizers in the organic paddy/rice field can increase methane (CH4) production, which leads to environmental problems. In this study, we aimed to determine the CH4 production potential (CH4-PP) by a soil profile from samples using flood incubation. Soil properties (chemical, physical, and biological) were analyzed from soil samples of three different paddy farming systems (organic, semi-organic, and conventional), whilst soil from teak forest was used as the control. A significant relationship was determined between soil properties and CH4-PP. The average amount of CH4-PP in the organic rice field profile was the highest among all the samples (1.36 µg CH4/kg soil/day). However, the CH4 oxidation potential (CH4-OP) is high as well, as this was a chance of mitigation options should focus on increasing the methanotrophic activity which might reduce CH4 emissions to the atmosphere. The factor most influencing CH4-PP is soil C-organic (Corg). Corg and CH4-PP of the top soil of organic rice fields were 2.09% and 1.81 µg CH4/kg soil/day, respectively. As a consequence, here the mitigation options require more efforts than in the other farming systems. Soil with various amounts of Corg reached a maximum point of CH4-PP at various time after incubation (20, 15, and 10 days for the highest, medium, and the lowest amounts of Corg, respectively). A high amount of Corg provided enough C substrate for producing a higher amount of CH4 and reaching its longer peak production than the low amount of Corg. These findings also provide guidance that mitigation option reduces CH4 emissions from organic rice fields and leads to drainage every10–20 days before reaching the maximum CH4-PP.

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Digital soil mapping: the challenge to obtain the best soil dataset and create a precise environmental model to support land use management at a national level (Ecuador).

10.5194/egusphere-egu2020-20873 ◽

2020 ◽

Author(s):

Daphne Armas ◽

Mário Guevara ◽

Fernando Bezares ◽

Rodrigo Vargas ◽

Pilar Durante ◽

...

Keyword(s):

Land Use ◽

Information System ◽

Soil Properties ◽

Soil Profile ◽

Soil Mapping ◽

Digital Soil Mapping ◽

Land Use Management ◽

National Scale ◽

Global Soil ◽

Soil Information

One of the biggest challenges for digital soil mapping is the limited of&#160;field&#160;soil information (e.g., soil profile descriptions, soil sample analysis) for representing soil variability across scales. Global initiatives such as the Global Soil&#160;Partnership&#160;(GSP) and the development of a Global Soil Information System&#160;(GloSIS), World Soil Information Service (WoSis) or SoilGrids250m for global pedometric mapping highlight new opportunities but the crescent need of new and better soil datasets across the world. Soil datasets are increasingly required for the development of soil monitoring baselines, soil protection and sustainable land use strategies, and to better understand the response of soils to global environmental change.&#160; However, soil surveys are a very challenging task due to their high acquisition costs such data and operational complexity. The use of legacy soil data can reduce these sampling efforts.The main objective of this research was the rescue, synthesis and harmonization of legacy&#160;soil profile information&#160;collected between 2009 and 2015 for different purposes (e.g., soil or natural resources inventory) across Ecuador. This project will support the creation of a soil information system at the national scale following international standards for archiving and sharing soil information (e.g., GPS or the GlobalSoilMap.net project). This new information could be useful to increase the accuracy of current digital soil information across the country and the future development of digital soil properties maps.We provided an integrated framework combining multiple data analytic tools (e.g., python libraries, pandas, openpyxl or pdftools) for the automatic conversion of text in paper format (e.g., pdf, jpg) legacy soil information, as much the qualitative soil description as analytical data, &#160;to usable digital soil mapping inputs (e.g., spatial datasets) across Ecuador. For the conversion, we used text data mining techniques to automatically extract the information. We based on regular expressions using consecutive sequences algorithms of common patterns not only to search for terms, but also relationships between terms. Following this approach, we rescued information of 13.696 profiles in .pdf, .jpg format and compiled a database consisting of 10 soil-related variables.The new database includes historical soil information that automatically converted a generic tabular database form (e.g., .csv) information.As a result, we substantially improved the representation of soil information in Ecuador that can be used to support current soil information initiatives such as the WoSis, Batjes et al. 2019, with only 94 pedons available for Ecuador, the Latin American Soil Information System (SISLAC, http://54.229.242.119/sislac/es),&#160; and the United Nations goals&#160; towards increasing soil carbon sequestration areas or decreasing land desertification trends.&#160; In our database there are almost 13.696 soil profiles at the national scale, with soil-related (e.g., depth, organic carbon, salinity, texture) with positive implications for digital soil properties mapping.&#160;With this work we increased opportunities for digital soil mapping across Ecuador. This contribution could be used to generate spatial indicators of land degradation at a national scale (e.g., salinity, erosion).This dataset could support new knowledge for more accurate environmental modelling and to support land use management decisions at the national scale.&#160;

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Land use changes after the period commodities rising price in the Rio Grande do Sul State, Brazil

Ciência Rural ◽

10.1590/0103-8478cr20160647 ◽

2017 ◽

Vol 47 (4) ◽

Cited By ~ 1

Author(s):

Vicente Celestino Pires Silveira ◽

◽

José Antonio González ◽

Eliana Lima da Fonseca ◽

◽

...

Keyword(s):

Land Use ◽

Atlantic Forest ◽

Rio Grande ◽

Raw Material ◽

Biodiesel Production ◽

World Population ◽

Rio Grande Do Sul ◽

Early 21St Century ◽

Pampa Biome ◽

The Impact

ABSTRACT: At the end of the 20th and early 21st century, agricultural systems incorporated definitively a new mission: to generate goods for a world population that continues to grow and whose way of life demand food with low environmental impact. Soybean is the main raw material for the production of biodiesel in Brazil, accountably responsible for 82.4% of the total produced between 2006 and 2013. The Brazilian state of Rio Grande do Sul (RS), which is formed by the Pampa and the Atlantic forest biomes, was responsible for 35.7% of the country's biodiesel production in the referred period. The aim of this paper was to verify the impact of the increased area of soybean cultivation in land use in Rio Grande do Sul State, in the period between 1990 and 2015, considering separately its two biomes (Pampa and Atlantic Forest) original areas, using both census dataset and satellite images. We used the period from 1990 to 2000 as before commodity rising price (BCRP) and the period from 2000 to 2013 as commodity rising price (CRP). The 505,162 ha from Atlantic Forest biome and 1,192,115ha from Pampa biome were added to soybean production in the CRP period. In the Atlantic Forest, this enlargement occurred in the border of the main production area, while in Pampa biome conversion of natural grassland to crop land was the main reason for the large increment in the cultivated area.

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