scholarly journals Phytosociology in areas of the Brazilian Cerrado: Cerrado stricto sensu, municipality of Porto Nacional, State of Tocantins

2020 ◽  
Vol 42 ◽  
pp. e50353
Author(s):  
Vanda Fernandes de Matos ◽  
Solange de Fátima Lolis ◽  
Ronaldo Rodrigues Coimbra ◽  
Rodney Haulien Oliveira Viana
Keyword(s):  
Monte Carlo ◽  
Wiener Index ◽  
Soil Samples ◽  
Conservation Strategies ◽  
Brazilian Cerrado ◽  
Monte Carlo Test ◽  
Soil Variables ◽  
Physical Chemical ◽  
Total Variability ◽  
Diameter Structure

Phytosociological studies are essential for the elaboration of conservation strategies for the Cerrado. The goal of this study was to survey two areas of cerrado stricto sensu: Fazenda Canaã and Fazenda Providência, located in the Municipality of Porto Nacional, State of Tocantins. There were 10 plots of 100 m2 allocated in each area. All individuals with circumference equal to or greater than 10 cm, at ground height ≥10 cm were sampled, soil samples were taken for physical-chemical analysis. Sampling in Canaã resulted in 379 individuals belonging to 28 families and 50 species. In Providência, there were 300 individuals from 27 families and 49 species. The Shannon-Wiener Index for the Canaã was 3.48 and for Providência, 3.45. The studied areas presented a large number of small sized individuals, presenting a reverse J-shaped diameter structure. The Canonical Correspondence Analysis showed significant scores for the first axes (p < 0.05) according to the Monte Carlo test, which explained 70% total variability of the data. The variables with the highest structure coefficient in axis 1 were clay (0.94), pH (0.62) and magnesium (-0.32). On axis 2, the most important variables were aluminum (0.29), silt (0.25) and potassium (-0.078). These soil variables show a differentiation of the study areas.

Crossover scaling in semidilute polymer solutions: a Monte Carlo test

1991 ◽  
Vol 1 (1) ◽  
pp. 37-60 ◽  
Author(s):  
Wolfgang Paul ◽  
Kurt Binder ◽  
Dieter W. Heermann ◽  
Kurt Kremer
Keyword(s):  
Monte Carlo ◽  
Polymer Solutions ◽  
Monte Carlo Test

scholarly journals KAJIAN ASPEK FISIKA, KIMIA, DAN BIOLOGI PERAIRAN SITU RAWABEBEK, KARAWANG, DALAM RANGKA PENGELOLAAN PERIKANAN BERBASIS BUDI DAYA

2016 ◽  
Vol 1 (1) ◽  
pp. 115
Author(s):  
Bambang Gunadi ◽  
Supriyono Eko Wardoyo
Keyword(s):  
Water Level ◽  
Diversity Index ◽  
Gonadosomatic Index ◽  
Stable Condition ◽  
Aquatic Organism ◽  
Wiener Index ◽  
Quality Parameters ◽  
Average Value ◽  
Physical Chemical ◽  
Biological Aspects

Penelitian tentang aspek-aspek fisika, kimia, dan biologi perairan bekas galian pasir telah dilakukan di Situ Rawabebek Kabupaten Karawang. Tujuan penelitian adalah untuk mendapatkan data dasar bagi penyusunan model pengelolaan perikanan di perairan bekas galian pasir berdasarkan prinsip perikanan berbasis budi daya (culture-based fisheries, CBF). Hasil pengamatan menunjukkan bahwa fluktuasi air di Situ Rawabebek mencapai hingga 1,90 m dan sangat dipengaruhi oleh ketinggian air Sungai Citarum. Nilai semua parameter kualitas air berada dalam kisaran yang layak untuk mendukung kehidupan ikan sementara kadar logam berat berada dalam ambang aman untuk kehidupan organisme akuatik termasuk ikan dan kesehatan manusia. Indeks keragaman plankton (Indeks Shanon-Wiener) pada setiap stasiun dan musim pengamatan berkisar antara 3,95—4,52 yang berarti bahwa komunitas plankton di Situ Rawabebek stabil dan perairannya dalam kondisi belum tercemar. Jenis ikan yang teramati untuk mengetahui pola reproduksinya di Situ Rawabebek antara lain lalawak (Puntius bramoides), paray (Rasbora argyrotaenia), dan seren (Cyclocheilichthys apogon) dengan tingkat Indeks Kematangan Gonad (IKG) masing-masing 3,43%; 12,82%; dan 3,95%. Dari analisis terhadap kondisi fisika, kimia, dan biologinya disimpulkan bahwa perairan bekas galian pasir Situ Rawabebek cukup layak untuk pengembangan perikanan berbasis budi daya.A study on the physical, chemical, and biological aspects of the abandoned sand mining reservoir was conducted in Rawabebek Reservoir (Karawang Regency, West Java). This study aimed to develop a model of fisheries management in the reservoir based on the culture based fisheries (CBF) system. The study showed that the fluctuation of water level in the Rawabebek Reservoir was monitored up to 1.90 m and highly influenced by the water level of Citarum River. The average value of all water quality parameters and heavy metals were in the suitable range for aquatic organism, fish and human health. The diversity index of plankton (Shanon-Wiener Index) at each station and sampling time observed, were ranged between 3.95 to 4.52 implied that the plankton community in the Rawabebek Reservoir was in the stable condition with no water pollution. Three fish species were observed for reproduction pattern in the Rawabebek Reservoir namely lalawak (Puntius bramoides), paray (Rasbora argyrotaenia), and seren (Cyclocheilichthys apogon) with the Gonadosomatic Index (GSI) were 3.43%, 12.82%, and 3.95%, respectively. Due to those physical, chemical and biological aspects, it was concluded that Rawabebek Reservoir was suitable for culture based fisheries (CBF) management system.

scholarly journals Relationship between soil oxidizable carbon and physical, chemical and mineralogical properties of umbric ferralsols

2011 ◽  
Vol 35 (1) ◽  
pp. 25-40 ◽  
Author(s):  
Flávio Adriano Marques ◽  
Márcia Regina Calegari ◽  
Pablo Vidal-Torrado ◽  
Peter Buurman
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Clay Content ◽  
Selective Extraction ◽  
Total Carbon ◽  
Soil Matrix ◽  
Soil Variables ◽  
Physical Chemical ◽  
Mineralogical Properties ◽  
Extractable Al

The occurrence of Umbric Ferralsols with thick umbric epipedons (> 100 cm thickness) in humid Tropical and Subtropical areas is a paradox since the processes of organic matter decomposition in these environments are very efficient. Nevertheless, this soil type has been reported in areas in the Southeast and South of Brazil, and at some places in the Northeast. Aspects of the genesis and paleoenvironmental significance of these Ferralsols still need a better understanding. The processes that made the umbric horizons so thick and dark and contributed to the preservation of organic carbon (OC) at considerable depths in these soils are of special interest. In this study, eight Ferralsols with a thick umbric horizon (UF) under different vegetation types were sampled (tropical rain forest, tropical seasonal forest and savanna woodland) and their macromorphological, physical, chemical and mineralogical properties studied to detect soil characteristics that could explain the preservation of high carbon amounts at considerable depths. The studied UF are clayey to very clayey, strongly acidic, dystrophic, and Al-saturated and charcoal fragments are often scattered in the soil matrix. Kaolinites are the main clay minerals in the A and B horizons, followed by abundant gibbsite and hydroxyl-interlayered vermiculite. The latter was only found in UFs derived from basalt rock in the South of the country. Total carbon (TC) ranged from 5 to 101 g kg-1 in the umbric epipedon. Dichromate-oxidizable organic carbon represented nearly 75 % of TC in the thick A horizons, while non-oxidizable C, which includes recalcitrant C (e.g., charcoal), contributed to the remaining 25 % of TC. Carbon contents were not related to most of the inorganic soil variables studied, except for oxalate-extractable Al, which individually explained 69 % (P < 0.001) of the variability of TC in the umbric epipedon. Clay content was not suited as predictor of TC or of the other studied C forms. Bulk density, exchangeable Al3+, Al saturation, ECEC and other parameters obtained by selective extraction were not suitable as predictors of TC and other C forms. Interactions between organic matter and poorly crystalline minerals, as indicated by oxalate-extractable Al, appear to be one of the possible organic matter protection mechanisms of these soils.

scholarly journals Dynamics of top-down factors with relation to ecological attributes of an endangered species Commiphora wightii

2016 ◽  
Vol 8 (3) ◽  
pp. 1556-1564 ◽  
Author(s):  
R. N. Kulloli ◽  
Manish Mathur ◽  
Suresh Kumar
Keyword(s):  
Soil Samples ◽  
Available Phosphorus ◽  
Top Down ◽  
Commiphora Wightii ◽  
Ecological Attributes ◽  
Soil Variables ◽  
Explanatory Factors ◽  
Ecological Variables ◽  
Total Soil Nitrogen

Present study was aimed to explore the influence of top down factors on ecological attributes of Commiphora wightii collected from seven districts of arid and semi arid parts of the Rajasthan. Ecological variables in respect of 46 accessions of this species were quantified. To assess the explanatory factors governing quantified ecological variables, soil samples were collected to analyze soil texture, soil EC, pH, available potassium, available phosphorus and total soil nitrogen. Results showed that there was a specific relationship between soil variables and occurence of C. wightii. The mid ranges of potassium (200-300 kg/ha) emerged as favourable to have better density and health of C. wightii: This is the first report on regulatory role of potassium on distribution and occurrence of C. wightii.

scholarly journals Biological activity of soils cultivated with yacón (Smallanthus sonchifolius Poep. & Endl) H. Robinson, inoculated with Azospirillum brasilense and native mycorrhizal fungi

2021 ◽  
Vol 38 (1) ◽  
pp. 125-133
Author(s):  
María Gabriela Di Barbaro ◽  
Horacio Enrique Andrada ◽  
Eleodoro Eduardo Del Valle ◽  
Celia Inés Brandán
Keyword(s):  
Biological Activity ◽  
Mycorrhizal Fungi ◽  
Azospirillum Brasilense ◽  
Microbial Consortium ◽  
Soil Samples ◽  
Biological Processes ◽  
Smallanthus Sonchifolius ◽  
Physical Chemical ◽  
Promote Plant Growth ◽  
Time Of Harvest

The soil is influenced by the roots of plants because the exudate radicals affect its physical, chemical, and biological processes. The aim of this research was to evaluate the microbial activity of soils cultivated with yacón (Smallanthus sonchifolius Poep. & Endl) H. Robinson and inoculated with microorganisms which promote plant growth. The experimental design used was randomized blocks with three repetitions per treatment. Each repetition corresponded to a 3m x 3m plot with 25 plants, in 5 cultivation lines with a distance of 70 cm apart. Four treatments were applied at the time of plantation. These consisted of yacón propagules inoculated with Azospirillum brasilense (T1) and native mycorrhizal fungi (T2) inoculated with the microbial consortium (T3). In the control treatments, the propagules were not inoculated with these microorganisms (T0). Soil samples were collected in lots cultivated with yacón located in the Province of Catamarca, in the northwest of Argentina. The samples were collected at the time of implantation and harvest during three agricultural cycles. The total Biological Activity (TBA) of the collected samples was determined by Fluorescein Diacetate Hydrolysis. The TBA of the soil was affected by the different crop treatments, which rose in the analyzed soils and was statistically different from the control treatments. Significant differences were also observed between the TBA of the soils at the beginning of the crops in comparison with the recorded values of the crop at the time of harvest. The inoculation of yacón propagules with A. brasilense and native mycorrhizal fungi affects the TBA of the cultivated soils marking a significant increase.

scholarly journals Selecting soil quality indicators for different soil management systems in the Brazilian Cerrado

2016 ◽  
Vol 51 (9) ◽  
pp. 1643-1651 ◽  
Author(s):  
Diane Cristina Stefanoski ◽  
Cícero Célio de Figueiredo ◽  
Glenio Guimarães Santos ◽  
Robélio Leandro Marchão
Keyword(s):  
Soil Quality ◽  
Quality Indicators ◽  
Soil Depth ◽  
Principal Component ◽  
Soil Management ◽  
Biological Indicators ◽  
Management Systems ◽  
Brazilian Cerrado ◽  
Soil Quality Indicators ◽  
Physical Chemical

Abstract The objective of this work was to assess soil quality indicators obtained with different datasets to compare soil management systems in the Brazilian Cerrado. Three criteria were used to select soil physical, chemical, and biological indicators: the full set of indicators obtained, with 36 parameters, for which all the physical, chemical, and biological soil properties were determined; a subset of indicators selected by principal component analysis (20 parameters); and a subset of indicators with some frequency of use in the literature (16 parameters). These indicators were obtained from the following management systems: no-tillage, conventional tillage, and native cerrado vegetation. Soil samples were collected at 0.0-0.1-m soil depth, and soil quality indicators were subjected to analysis of variance and their means were compared. The incorporation of soil native cerrado into agriculture decreased soil quality. The most commonly used indicators in the scientific literature are sensitive enough to detect differences in soil quality according to land use. Therefore, the selection of a minimum set of representative data can be more useful than a complex set of properties to compare management systems as to their soil quality.

Template-Based Monte-Carlo Test Generation for Simulink Models

2019 ◽  
pp. 63-78 ◽  
Author(s):  
Takashi Tomita ◽  
Daisuke Ishii ◽  
Toru Murakami ◽  
Shigeki Takeuchi ◽  
Toshiaki Aoki
Keyword(s):  
Monte Carlo ◽  
Test Generation ◽  
Monte Carlo Test
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