scholarly journals Characterization and Analysis of Gullies in the Sub-basin of Ribeirão Serra in Morrinhos, Goias, Brazil

2019 ◽  
Vol 11 (11) ◽  
pp. 70
Author(s):  
Breno A. da Silva ◽  
Pedro R. Giongo ◽  
Thais A. Barbosa ◽  
Victor H. Moraes ◽  
Thomas J. Cavalcante ◽  
...  

Due to the reduction of the vegetation cover, the exposed soil increases the erosive vulnerability, and reduces the organic matter content, factors that can aggravate with less production of vegetal mass and microbiological activity of the arable layers, rich in calcium carbonate and that increases the degradation of the soil structure leading to the formation of gullies. This study aimed to characterize and survey the physical, chemical and structural characteristics of soils of four gullies located in the sub-basin of Ribeirao Serra by means of physical-chemical parameters and subjected to multivariate analysis. Slope maps, hypsometry, drainage network and soil types were elaborated. Morphological description of the soil, georeferencing of the boundaries of each gullie, and collection of deformed soils samples for physical-chemical and structural analysis were performed. Soil samples were collected on the slopes of the gullies at three points of each erosion, with three replicates, one in each horizon (A, B and C) at depths ranging from 0 to 310 cm. Qualitative tests were also carried out to verify the presence of some substances in the soil, such as carbonates and manganese. The data were submitted to the multivariate analysis, by means of Discriminant Analysis of Partial Least Squares analysis to evaluate the grouping of gullies in relation to the analyzed elements (physical-chemical), identifying if the set of elements interact with each other and/or present similarities. There is a high degree of anthropization with the use of pasture cultivated around the four gullies studied. According to the multivariate analysis the gullies Barreiro, Vendinha and Capim, are different, while it resembles the gull of the Retreat with the gullies Vendinha and Capim. The chemical elements present greater weight than the physical ones, in the separation of the gullies through the multivariate model.

1983 ◽  
Vol 36 (2) ◽  
pp. 191 ◽  
Author(s):  
D Keast ◽  
C Tonkin

Soil pH, soil moisture content and soil organic matter content did not appear to influence significantly the total numbers of actinomycetes isolated from sample sites in Western Australia. However, seasonal influences exist with summer conditions leading to higher spore isolation. Substantial but non-specific antifungal activity against Phytophthora cinnamomi, P. cryptogea, P. nicotiana, Pythium proli/erum and L. laccata was detected in vitro from many of the 2367 actinomycetes isolated. Antifungal activity mayor may not occur in members of the same actinomycete group, suggesting segregation of antifungal capacity within all groups. A limited number of actinomycete groups was isolated from the rhizosphere of plants and these exhibited similar properties to their counterparts in soil or litter. Actinomycetes isolated from the rhizosphere of Pinus radiata produced a high degree of in vitro antifungal activity against the Phytophthora species but, in general, actinomycetes isolated from root surfaces exhibited antibiosis against all the fungi tested. More actinomycetes showed antifungal activity from soils where P. cinnamomi was causing dieback of jarrah and other understorey species.


2008 ◽  
Vol 8 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Yusmadi Yusmadi ◽  
Nahrowi Nahrowi ◽  
Muhammad Ridla

The quality and palatibility of silage and hay complete ration based on organic primer garbage in peranakan etawah (PE) poadABSTRACT. This research was conducted to study the quality and palatability of silage and hay complete ration based on organic primer garbage in nine heads of Peranakan Etawah (PE) Goat. The quality of silage and hay was evaluated By measuring pH, total number of lactic acid Bacteria (LAB), palatability, dry matter (DM) and organic matter (OM) aroma and color of silage. Nine heads of peranakan etawah were grouped based on their lactation periode and randomly assigned to one of tree dietary treatments. The treatments were (1) Control rations; (2) silage complete ration (SRK); and (3) Hay complete ration (HRK). The results indicated that the silage had PH 4.15 and total number of LAB was 2.4 x 10 cfu/g of silage. Dry matter and organic matter digestibility of SRK were better than those of HRK. The palatability of SRK was higher than HRK but less than control. Storage of SRK for did not change dry matter and organic matter content. Organoleptic analysis indicated that texture and color of HRK were changed at after storage, while SRK was still constant. It is concluded that silage composed of organic primer garbage has high quality in terms of physical, chemical and microbial characteristics, prolong storage.


2018 ◽  
Vol 13 (No. 3) ◽  
pp. 140-149 ◽  
Author(s):  
Šimanský Vladimír ◽  
Lukáč Martin

Soil structure is a key determinant of many soil environmental processes and is essential for supporting terrestrial ecosystem productivity. Management of arable soils plays a significant role in forming and maintaining their structure. Between 1994 and 2011, we studied the influence of soil tillage and fertilisation regimes on the stability of soil structure of loamy Haplic Luvisol in a replicated long-term field experiment in the Dolná Malanta locality (Slovakia). Soil samples were repeatedly collected from plots exposed to the following treatments: conventional tillage (CT) and minimum tillage (MT) combined with conventional (NPK) and crop residue-enhanced fertilisation (CR+NPK). MT resulted in an increase of critical soil organic matter content (St) by 7% in comparison with CT. Addition of crop residues and NPK fertilisers significantly increased St values (by 7%) in comparison with NPK-only treatments. Soil tillage and fertilisation did not have any significant impact on other parameters of soil structure such as dry sieving mean weight diameters (MWD), mean weight diameter of water-stable aggregates (MWD<sub>WSA</sub>), vulnerability coefficient (Kv), stability index of water-stable aggregates (Sw), index of crusting (Ic), contents of water-stable macro- (WSA<sub>ma</sub>) and micro-aggregates (WSA<sub>mi</sub>). Ic was correlated with organic matter content in all combinations of treatments. Surprisingly, humus quality did not interact with soil management practices to affect soil structure parameters. Higher sums of base cations, CEC and base saturation (Bs) were linked to higher Sw values, however higher values of hydrolytic acidity (Ha) resulted in lower aggregate stability in CT treatments. Higher content of K<sup>+</sup> was responsible for higher values of MWD<sub>WSA </sub>and MWD in CT. In MT, contents of Ca<sup>2+</sup>, Mg<sup>2+ </sup>and Na<sup>+</sup> were significantly correlated with contents of WSA<sub>mi </sub>and WSA<sub>ma</sub>. Higher contents of Na<sup>+</sup> negatively affected St values and positive correlations were detected between Ca<sup>2+</sup>, Mg<sup>2+ </sup>and Na<sup>+</sup> and Ic in NPK treatments.


Author(s):  
Vito Ferro ◽  
Vincenzo Bagarello

Field plots are often used to obtain experimental data (soil loss values corresponding to different climate, soil, topographic, crop, and management conditions) for predicting and evaluating soil erosion and sediment yield. Plots are used to study physical phenomena affecting soil detachment and transport, and their sizes are determined according to the experimental objectives and the type of data to be obtained. Studies on interrill erosion due to rainfall impact and overland flow need small plot width (2–3 m) and length (< 10 m), while studies on rill erosion require plot lengths greater than 6–13 m. Sites must be selected to represent the range of uniform slopes prevailing in the farming area under consideration. Plots equipped to study interrill and rill erosion, like those used for developing the Universal Soil Loss Equation (USLE), measure erosion from the top of a slope where runoff begins; they must be wide enough to minimize the edge or border effects and long enough to develop downslope rills. Experimental stations generally include bounded runoff plots of known rea, slope steepness, slope length, and soil type, from which both runoff and soil loss can be monitored. Once the boundaries defining the plot area are fixed, a collecting equipment must be used to catch the plot runoff. A conveyance system (H-flume or pipe) carries total runoff to a unit sampling the sediment and a storage system, such as a sequence of tanks, in which sediments are accumulated. Simple methods have been developed for estimating the mean sediment concentration of all runoff stored in a tank by using the vertical concentration profile measured on a side of the tank. When a large number of plots are equipped, the sampling of suspension and consequent oven-drying in the laboratory are highly time-consuming. For this purpose, a sampler that can extract a column of suspension, extending from the free surface to the bottom of the tank, can be used. For large plots, or where runoff volumes are high, a divisor that splits the flow into equal parts and passes one part in a storage tank as a sample can be used. Examples of these devices include the Geib multislot divisor and the Coshocton wheel. Specific equipment and procedures must be employed to detect the soil removed by rill and gully erosion. Because most of the soil organic matter is found close to the soil surface, erosion significantly decreases soil organic matter content. Several studies have demonstrated that the soil removed by erosion is 1.3–5 times richer in organic matter than the remaining soil. Soil organic matter facilitates the formation of soil aggregates, increases soil porosity, and improves soil structure, facilitating water infiltration. The removal of organic matter content can influence soil infiltration, soil structure, and soil erodibility.


2011 ◽  
Vol 2011 ◽  
pp. 1-10
Author(s):  
Nathalia Flórez-Zapata ◽  
Daniel Uribe-Vélez

Nitrogen (N) plays an important role in agricultural production. This study was designed to evaluate the presence of cultivable N cycle-associated microorganisms (nitrogen-fixing bacteria—NFB, proteolytic bacteria—PR, ammonifiers—AMO, ammonium-oxidizing bacteria—AOB, nitrite-oxidizing bacteria—NOB, and denitrifiers—DEN), and their relationship with physical-chemical and agronomic soil descriptors, inSolanum phurejarhizospheric soil samples, from traditional and organic crop management farms. A cluster analysis with the physical and chemical properties of soil, allowed to identify the organic matter content as an important factor that determines the outcome of that grouping. Significant differences () between farms were found in the abundance of this groups, but correlation analysis showed that proteolytic and nitrogen fixing bacteria were the main nitrogen associated functional groups affected by soils' physical-chemical characteristics. The amount of ammonia available is affected by the agricultural management strategy, which consequently affects the NFB abundance. Finally the results showed that PR, protease activity and soil properties related with organic matter transformation has a positive relationship with productivity, which given the high organic matter content of the Andean soils being studied, we conclude that nitrogen mineralization process has an important role in the nitrogen cycle and its bioavailability in this ecosystem.


2019 ◽  
Vol 11 (1) ◽  
Author(s):  
Leandro Campos Pinto ◽  
Wantuir Filipe Teixeira Chagas ◽  
Francisco Hélcio Canuto Amaral

The relationship of management and soil quality may be evaluated by the behavior of soil physical, chemical and biological properties. In the assessment of soil structure, it is sought attributes in the view of measuring the porosity and the distribution of pores by size and its implication to permeability and rigidity of the pores, as well as the stability of the units that composes soil structure. The aim of this research was to assess the structure of a Dystroferric Red Latosol (Oxisol) under conventional corn crop, conventional coffee crop, eucalyptus crop and an equilibrium reference (native vegetation), by the determination of the particle density, bulk density, calculated total porosity, microporosity, macroporosity, moisture saturation, determined total porosity, blocked pores and aggregated stability. Soil under native vegetation presented the lowest values of particle density, probably due to the greatest soil organic matter content in this environment. It was verified a tendency of increasing blocked pores and decreasing bulk density. As expected, bulk density varied from 0.87 to 1.03 g cm-3, showing an inversely proportional distribution related to total porosity. The largest values of geometric mean diameter presented by the soil under native vegetation are due to thegreater structuration degree of this soil, which contributes to the stabilization of the aggregates in this environment. The native vegetation environment presented a better soil physical quality in relation to other land uses.


Author(s):  
Alper Durak ◽  
Özlem Altuntaş ◽  
İbrahim Kutalmış Kutsal ◽  
Rabia Işık ◽  
Fırat Ege Karaat

Due to its importance for organic agriculture, one of the most important agricultural production systems, various sources have been proposed to increase soil organic matter content. Vermicompost is one of those sources known as the resistant last form of farmyard manure which is degraded by earthworms. Soil organic matter or humus and their compounds are nutrient sources that increase physical, chemical and biological quality of soil. Humus and humus compounds improve soil physical, chemical and biological quality parameters increasing rhizosphere aeration and water holding capacity, rehabilitating soil structure, providing plant nutrients and constituting natural media for microorganisms with their regulative effects on soil reactions. In this study, the effects of vermicompost on yield and some growth parameters of lettuce were investigated. For this purpose, a random block designed experiment with 5 different applications was conducted in 3 replicates. The applications were control, vermicompost applications of 100 kg, 200 kg and 300 kg per decare and conventional fertilization. According to the results obtained, yield and growth parameters were improved by vermicompost application when compared to control and conventional fertilization. As a result of this study, it was concluded that 300 kg vermicompost/da is a promising application in lettuce production for optimal yield and soil improvement.


2022 ◽  
Vol 43 (1) ◽  
pp. 7-24
Author(s):  
Iris Mariane da Silva Martins ◽  
◽  
Tatiane Carla Silva ◽  
Maria Julia Betiolo Troleis ◽  
Paulino Taveira de Souza ◽  
...  

Effects of soil attributes using the geostatistical tool improves the interpretation of specific soil management. Thus, this study aimed to evaluate the physical, chemical, and microbiological properties of a Typical Haplustox (Oxisol), identifying those with the best linear and spatial correlation with eucalyptus (Eucalyptus spp.) vegetative growth. The experiment was conducted at the Teaching, Research, and Extension Farm (FEPE) of the Universidade Estadual Paulista (UNESP), Campus of Ilha Solteira. Thirty-five points spaced 13 meters apart were demarcated for analysis, which were distributed in 5 rows of 7 points each. From each point, 2 soil samples were collected from the 0-10 cm depth layer. The physical, chemical, and microbiological soil properties evaluated were: sand, silt, and clay contents; penetration resistance (PR), gravimetric moisture (GM), real density (RD), microbial biomass carbon (MBC), respirometry (CO2-C), metabolic quotient (qCO2), organic matter content (OM), and hydrogenionic potential (pH). The eucalyptus attributes assessed were: plant height (PH) and circumference at breast height (CBH). Each attribute was analyzed by descriptive statistics using the SAS software. Data frequency distribution was verified by the Shapiro Wilk method, and geospatial changes were analyzed by the GS+ software. The soil property that best explained the variability in eucalyptus dendrometric attributes was real density (RD). Except for RD, all properties did not show spatial dependence (i.e., pure nugget effect), which significantly represents eucalyptus vegetative performance.


2021 ◽  
Author(s):  
Katharina Meurer ◽  
Thomas Keller ◽  
Nicholas Jarvis

&lt;p&gt;The pore structure of soil is known to be dynamic at time scales ranging from seconds (e.g. compaction) to seasons (e.g. root growth, macro-faunal activity) and even decades to centuries (e.g. changes in organic matter content). Nevertheless, soil physical and hydraulic functions are generally treated as static properties in most soil-crop models. Some models account for seasonal variations in soil properties (e.g. bulk density) due to tillage loosening and post-tillage consolidation or soil sealing. However, no model can account for longer-term changes in soil structure due to biological agents and processes. The development of such a model remains a challenge due to the enormous complexity of the interactions in the soil-plant system. Here, we present a new concept for modelling soil structure evolution impacted by biological processes such as root growth and earthworm activity. In this preliminary test of the model, we compare simulations against field observations made at the Soil Structure Observatory (SSO) in Z&amp;#252;rich, Switzerland, that was designed to provide information on soil structure recovery following a severe compaction event. In this simple application, we modelled changes in the pore size distribution in a bare soil treatment resulting from soil ingestion and egestion by earthworms and the loosening of compacted soil by casting at the soil surface. Following calibration, the model was able to reproduce the observed temporal development of total porosity, soil bulk density and pore size distribution during a four-year period following severe traffic compaction. The modelling approach presented here appears promising and could help support the development of cost-efficient strategies for sustainable soil management and the restoration of degraded soils.&lt;/p&gt;


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