Cerrado Ecosystem Research Articles

Annual variation in soil respiration and its component parts in two structurally contrasting woody savannas in Central Brazil

Background and aims: Due to the high spatial and temporal variation in soil CO₂ efflux, terrestrial carbon budgets rely on a detailed understanding of the drivers of soil respiration from a diverse range of ecosystems and climate zones. In this study we aim to evaluate the independent influence of vegetation structure and climate on soil CO₂ efflux within cerrado ecosystems. Methods: We examine the seasonal and diel variation of soil CO₂ efflux, including its autotrophic and heterotrophic components, within two adjacent and structurally contrasting woody savannas in central Brazil. Principle results: We found no significant difference in the annual soil CO₂ efflux between the two stands (p=0.53) despite a clear disparity in both LAI (p<0.01) and leaf litterfall (p<0.01). The mean annual loss of carbon from the soil was 17.32(± 1.48) Mg Cha⁻¹ of which approximately 63% was accounted for by autotrophic respiration. The relative contribution of autotrophic respiration varied seasonally between 55% in the wet season to 79% of the total soil CO₂ efflux in the dry season. Furthermore, seasonal fluctuations of all the soil respiration components were strongly correlated with soil moisture (R²=0.79-0.90, p<0.01). Conclusions: Across these two structurally distinct cerrado stands, seasonal variations in rainfall, was the main driver of soil CO₂ efflux and its components. Consequently, soil respiration within these ecosystems is likely to be highly sensitive to any changes in seasonal precipitation patterns.

Wickerhamiella pagnoccae sp. nov. and Candida tocantinsensis sp. nov., two ascomycetous yeasts from flower bracts of Heliconia psittacorum (Heliconiaceae)

Two novel yeast species were isolated from nectar of flower bracts of Heliconia psittacorum (Heliconiaceae) collected in a Cerrado ecosystem in the state of Tocantins, northern Brazil. Wickerhamiella pagnoccae sp. nov., which is closely related to Candida jalapaonensis, is heterothallic and produces one spheroid ascospore per ascus. Candida tocantinsensis sp. nov. belongs to the Metschnikowiaceae clade and its nearest relative is Candida ubatubensis, but the sequence identity (%) in the D1/D2 domains of the rRNA gene is low. The type strain of W. pagnoccae is UFMG-F18C1(T) ( = CBS 12178(T) = NRRL Y-48735(T)) and the type strain of C. tocantinsensis is UFMG-F16D1(T) ( = CBS 12177(T) = NRRL Y-48734(T)).

Activity of some hypocrealean fungi collected in a Cerrado ecosystem against Rhodnius spp. (Hemiptera: Reduviidae) under laboratory conditions

The hypocrealean invertebrate-pathogenic fungi Lecanicillium psalliotae, Paecilomyces lilacinus and Pochonia chlamydosporia isolated from soils in Central Brazil were tested against palm-dwelling Rhodnius neglectus, R. nasutus, R. prolixus, and R. robustus; all of these insects are vectors of Chagas disease. Particularly R. neglectus and R. nasutus, which are both important secondary intruders of human habitations were susceptible to all three of the fungi tested, and fungi sporulated successfully on the cadavers. This is the first report of activity of L. psalliotae, P. lilacinus and P. chlamydosporia against Rhodnius spp., and these fungi have interest for integrated control of triatomine vectors.

Comparative biogeography of Chromobacterium from the neotropics

The genus Chromobacterium encompasses free-living Gram-negative bacteria. Until 2007, the genus consisted of only one species but six species are now recognized. Chromobacterium violaceum is the type species of the genus and is commonly found in soil and water in tropical and sub-tropical regions. We have investigated a collection of 111 isolates displaying violet pigmentation from undisturbed aquatic and soil environments from Brazilian Cerrado ecosystem. The 16S rRNA gene phylogeny revealed that all isolates were allocated in a monophyletic cluster inside the Chromobacterium genus and formed few clusters related most closely with Chromobacterium piscinae. The two sets of isolates from water and soil were analyzed by the repetitive extragenic palindromic (rep)-PCR genomic fingerprinting technique using a BOX-AR1 primer. The antimicrobial susceptibility and the different carbon sources utilized by these isolates were also investigated. Physiological profiles of the isolates generated by BIOLOG GN2 plates showed great versatility in the substrate utilization, much higher than the C. violaceum ATCC 12472. All isolates exhibited a high minimum inhibitory concentration (MIC) to ampicillin (MIC>512μg/ml) and were inhibited by ciprofloxacin, tetracycline and mercury at the lowest concentration tested (MIC<2μg/ml). Thirteen BOX-PCR band patterns were identified from 33 individual fingerprints. Eleven patterns provided evidence for endemic distributions. Antimicrobial susceptibility and BOX-PCR fingerprint clustering showed a clear distinction between Chromobacterium isolates from the water and soil. The results suggested that microenvironment barriers such as water and soil can play an important role in the periodic selection and diversification of Chromobacterium population ecotypes.

Canopy Herbivory and Insect Herbivore Diversity in a Dry Forest–Savanna Transition in Brazil

ABSTRACTThis study aimed to compare canopy herbivore diversity and resultant insect damage to vegetation in two distinct and adjacent ecosystems, specifically a dry forest ecosystem and a cerrado (savanna) ecosystem that occur together in an abrupt transition zone in southeastern Brazil. In the dry forest, the canopy was reached using a single rope climbing technique, whereas the shorter canopy of the cerrado was assessed using a 7 m ladder. Insect specimens were collected by beating the foliage, and 20 representative leaves were collected to calculate the specific leaf mass (SLM) and leaf area loss through herbivory. Also, we collected ten soil samples from each habitat to determine soil nutrient content. We sampled 118 herbivorous insects from ten families, mostly in dry forest trees (96 individuals belonging to 31 species). A higher abundance of chewing and sap‐sucking insects were observed in dry forest trees than in cerrado trees. The same pattern was observed for the richness of chewers, with a higher degree of diversity of chewers found in dry forest trees than in cerrado trees. Herbivorous insects were not affected by SLM regardless of guild and habitat. However, we observed a negative correlation between the herbivory rate and the specific leaf mass (SLM). The cerrado trees showed a higher SLM and lower herbivory rates than trees occurring in the dry forest. These results suggest that herbivory rates in the transition dry forest–cerrado may be driven by soil nutrient content, which is thought to influence leaf sclerophylly.

Spathaspora arborariae sp. nov., a d-xylose-fermenting yeast species isolated from rotting wood in Brazil

Four strains of a new yeast species were isolated from rotting wood from two sites in an Atlantic Rain Forest and a Cerrado ecosystem in Brazil. The analysis of the sequences of the D1/D2 domains of the large-subunit rRNA gene showed that this species belongs to the Spathaspora clade. The new species ferments D-xylose efficiently and is related to Candida jeffriesii and Spathaspora passalidarum, both of which also ferment D-xylose. Similar to S. passalidarum, the new species produces unconjugated asci with a single greatly elongated ascospore with curved ends. The type strain of Spathaspora arborariae sp. nov. is UFMG-HM19.1A(T) (=CBS11463(T)=NRRL Y-48658(T)).

Isotopic view of vegetation and carbon and nitrogen cycles in a cerrado ecosystem, southeastern Brazil

Carbon and nitrogen biogeochemical cycles in savannas are strongly regulated by the seasonal distribution of precipitation and pulses of nutrients released during the wetting of the dry soil and are critical to the dynamics of microorganisms and vegetation. The objective of this study was to investigate the spatial and temporal variability of C and N isotope ratios as indicators of the cycling of these elements in a cerrado sensu stricto area, within a protected area in a State Park in the state of São Paulo, Brazil. The foliar δ13C and δ15N values varied from -33.6 to -24.4 ‰ and -2.5 to 4.5 ‰, respectively. The δ13C values showed a consistent relationship with canopy height, revealing the importance of structure of the canopy over the C isotopic signature of the vegetation. Carbon isotopic variations associated with the length of the dry season indicated the importance of recent fixed C to the integrated isotopic signature of the leaf organic C. The studied Cerrado species showed a depleted foliar δ15N, but a wide range of foliar Nitrogen with no difference among canopy heights. However, seasonal variability was observed, with foliar δ15N values being higher in the transition period between dry and rainy seasons. The variation of the foliar C and N isotope ratios presented here was consistent with highly diverse vegetation with high energy available but low availability of water and N.

Occurrence of invertebrate-pathogenic fungi in a Cerrado ecosystem in Central Brazil

Occurrence of invertebrate-pathogenic fungi in a protected area of the Cerrado region of Brazil is reported. Fungi were baited with triatomines, ticks, aquatic snails or mosquito larvae from substrates or collected from infected insects. The findings underscore the importance to preserve these fungi and to investigate their potential for vector control.

Wickerhamomyces queroliae sp. nov. and Candida jalapaonensis sp. nov., two yeast species isolated from Cerrado ecosystem in North Brazil

Two novel yeast species, Wickerhamomyces queroliae sp. nov. and Candida jalapaonensis sp. nov., were isolated, respectively, from larvae of Anastrepha mucronata (Diptera: Tephritidae) collected from ripe fruit of Peritassa campestris ('Bacupari', Hippocrateaceae) and from flowers of Centropogon cornutus (Campanulaceae) in the Cerrado ecosystem of the state of Tocantins, Brazil. Analysis of the D1/D2 large-subunit rRNA gene sequences placed W. queroliae in the Wickerhamomyces clade near Wickerhamomyces ciferri and Candida silvicultrix. Candida jalapaonensis belongs to the Wickerhamiella clade and is related to Candida drosophilae. The type strain of Wickerhamomyces queroliae is UFMG-05-T200.1(T) (=CBS 10936(T)=NRRL Y-48478(T)) and the type strain of Candida jalapaonensis is UFMG-03-T210(T) (=CBS 10935(T)=NRRL Y-48477(T)).

Reação de cultivares de soja à mela (Thanatephorus cucumeris) em campo em dois estádios de desenvolvimento das plantas

A mela, causada pelo fungo Thanatephorus cucumeris, é uma das principais doenças da cultura da soja no estado de Roraima. O objetivo deste trabalho foi avaliar a reação de 15 cultivares de soja à mela em condições de cerrado em Roraima. Os parâmetros avaliados foram a porcentagem de área foliar infectada (AFI) no estádio R.5.5 e a porcentagem de vagens com sintoma de mela (VM) no estádio R.6. Houve diferença significativa entre as cultivares testadas segundo o teste de Fisher LSD a 1% de probabilidade nas duas avaliações. A AFI variou de 1,5% (cv. Padre) a 62% (cv.BR-36) e a VM de 8% (cv.UFV-9 e cv. Juçara) a 55% (cv. BR-36). A correlação entre as duas avaliações foi significativa e positiva.

Expansion of gallery forests into central Brazilian savannas

AbstractUpland tropical forests have expanded and contracted in response to past climates, but it is not clear whether similar dynamics were exhibited by gallery (riparian) forests within savanna biomes. Because such forests generally have access to ample water, their extent may be buffered against changing climates. We tested the long‐term stability of gallery forest boundaries by characterizing the border between gallery forests and savannas and tracing the presence of gallery forest through isotopic analysis of organic carbon in the soil profile. We measured leaf area index, grass vs. shrub or tree coverage, the organic carbon, phosphorus, nitrogen and calcium concentrations in soils and the carbon isotope ratios of soil organic matter in two transitions spanning gallery forests and savanna in a Cerrado ecosystem. Gallery forests without grasses typically show a greater leaf area index in contrast to savannas, which show dense grass coverage. Soils of gallery forests have significantly greater concentrations of organic carbon, phosphorus, nitrogen and calcium than those of savannas. Soil organic carbon of savannas is significantly more enriched in 13C compared with that of gallery forests. This difference in enrichment is in part caused by the presence of C4 grasses in savanna ecosystem and its absence in gallery forests. Using the 13C abundance as a signature for savanna and gallery forest ecosystems in 1 m soil cores, we show that the borders of gallery forests have expanded into the savanna and that this process initiated at least 3000–4000 bp based on 14C analysis. Gallery forests, however, may be still expanding as we found more recent transitions according to 14C activity measurements. We discuss the possible mechanisms of gallery forest expansion and the means by which nutrients required for the expansion of gallery forest might accumulate.

Do herbivores exert top‐down effects in Neotropical savannas? Estimates of biomass consumption by leaf‐cutter ants

AbstractQuestion:Plant communities in Paleotropical savannas are regulated by a combination of bottom‐up and top‐down effects. However, the paucity of ungulates and other large herbivores in Neotropical savannas has led to speculation that these communities are primarily structured by physical factors such as fire, precipitation and soil chemistry. We addressed the following question: How much plant biomass is consumed by leaf‐cutter ants in Neotropical savannas, and is it comparable to the amount of biomass consumed by herbivores in Paleotropical savanna sites?Location:Our study was conducted at the Estação Ecológica do Panga, located 30 km south of Uberlândia, Minas Gerais, Brazil. All field work was conducted in the vegetation type known as cerrado sensu stricto.Methods and ResultsUsing direct measurements of herbivory, coupled with estimates of plant productivity and ant colony density, we found that leaf‐cutter ants (Atta spp.) consume 13–17% of the foliar biomass produced annually by woody plants in a Neotropical savanna (Brazilian cerrado). Although comparisons with other savanna systems are complicated by methodological differences among studies, the proportion of biomass consumed by Atta species is about 25% of that consumed by the entire ungulate community in some African savannas and greater than or comparable to the total herbivory observed in some terrestrial ecosystems.Conclusions:We hypothesize that this intense biomass consumption by Atta will have important ecological consequences for the cerrado ecosystem, because leaf‐cutter abundance increases in fragmented or degraded habitats. These effects are likely to be exacerbated as anthropogenic pressure in this biodiversity hotspot increases.

In vitro Propagation of Lychnophora pinaster (Asteraceae): A Threatened Endemic Medicinal Plant

Lychnophora pinaster, known as arnica, is a medicinal plant of the Cerrado ecosystem in Brazil. It is widely used in the form of alcoholic extract for its anti-inflammatory and anesthetic and healing effects on sprains, bruises, and inflammation. Owing to the great difficulty of propagation, it is listed by the Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis in the category of plants vulnerable to extinction. Micropropagation offers a solution to this problem by allowing the preservation and expansion of germplasm. The objective of this research was to establish a protocol for in vitro propagation of arnica. The best medium for germination of arnica embryos and plantlet growth was a quarter strength semisolid Murashige and Skoog medium (MS/4) containing 0.75% (w/v) sucrose. For shoot induction, the best results were obtained on MS/4 with 2.76 μm of benzylaminopurine. Maximum shoot elongation before rooting occurred in the presence of 8.67 μm of gibberellic acid for 19 d. Microshoots were successfully rooted in the presence of 10.7 μm of naphthalene acetic acid for 15 d. After rooted plantlets were acclimatized in a greenhouse for 20 d, the survival rate was 100% when planted in a soil from the area of occurrence of the species, whereas 0% survived when planted in Plantmax.

Removal of nutrient limitations by long-term fertilization decreases nocturnal water loss in savanna trees

Under certain environmental conditions, nocturnal transpiration can be relatively high in temperate and tropical woody species. We have previously shown that nocturnal sap flow accounts for up to 28% of total daily transpiration in woody species growing in a nutrient-poor Brazilian Cerrado ecosystem. In the present study, we assessed the effect of increased nutrient supply on nocturnal transpiration in three dominant Cerrado tree species to explore the hypothesis that, in nutrient-poor systems, continued transpiration at night may enhance delivery of nutrients to root-absorbing surfaces. We compared nocturnal transpiration of trees growing in unfertilized plots and plots to which nitrogen (N) and phosphorus (P) had been added twice yearly from 1998 to 2005. Three independent indicators of nocturnal transpiration were evaluated: sap flow in terminal branches, stomatal conductance (g(s)), and disequilibrium in water potential between covered and exposed leaves (DeltaPsi(L)). In the unfertilized trees, about 25% of the total daily sap flow occurred at night. Nocturnal sap flow was consistently lower in the N- and P-fertilized trees, significantly so in trees in the N treatment. Similarly, nocturnal g(s) was consistently lower in fertilized trees than in unfertilized trees where it sometimes reached values of 150 mmol m(-2) s(-1) by the end of the dark period. Predawn gs and the percentage of nocturnal sap flow were linearly related. Nocturnal DeltaPsi(L) was significantly greater in the unfertilized trees than in N- and P-fertilized trees. The absolute magnitude of DeltaPsi(L) increased linearly with the percentage of nocturnal sap flow. These results are consistent with the idea that enhancing nutrient uptake by allowing additional transpiration to occur at night when evaporative demand is lower may avoid excessive dehydration associated with increased stomatal opening during the day when evaporative demand is high.

Metschnikowia cerradonensis sp. nov., a yeast species isolated from ephemeral flowers and their nitidulid beetles in Brazil

A novel yeast species, Metschnikowia cerradonensis sp. nov., is described from 12 strains isolated from flowers of Ipomoea carnea and from beetles of the genus Conotelus in the Cerrado ecosystem in the region of Jalapão, Tocantins State, Brazil. Analysis of the sequences of the rRNA gene cluster suggested that M. cerradonensis is closely related to Metschnikowia santaceciliae, Metschnikowia continentalis and an undescribed species represented by strain UWOPS 00-154.1. These species mate together but ascospores are very rarely formed, showing that they represent distinct biological species. M. cerradonensis is apparently endemic to the Cerrado ecosystem of the Jalapão area. The type strain of M. cerradonensis is UFMG 03-T67.1(T) (h(+)) (=CBS 10409(T)=NRRL Y-48067(T)) and the designated allotype is UFMG 03-T68.1 (h(-)) (=CBS 10410=NRRL Y-48068).

Diversidade de morcegos (Mammalia, Chiroptera) do Complexo Aporé-Sucuriú, Mato Grosso do Sul, Brasil

Realizou-se um inventário da fauna de morcegos entre abril e novembro de 2004 no norte de Mato Grosso do Sul, Brasil (Projeto Jauru/MMA). Oito pontos de coleta foram amostrados com redes-neblina em um ambiente de cerrado, sendo capturados 146 indivíduos de 28 espécies, distribuídos em seis famílias. O total de espécies neste estudo, representa apenas 30% da fauna de morcegos do cerrado. A família mais capturada foi a Phyllostomidae, representada por Glossophaga soricina (Pallas, 1766) e Artibeus lituratus (Olfers, 1818). Algumas espécies raras foram capturadas: Lophostoma brasiliense (Peters, 1866), Lonchophylla mordax Thomas, 1903 e Lionycteris spurrelli Thomas, 1913. O local de maior abundância (0,032 indivíduos/m²/h) mostrou um índice de Simpson de D = 3.86 e o de menor abundância (0,003 indivíduos/m²/h) um índice de Simpson de D = 3.03. A preservação dos mananciais de água e a cobertura florestal nestes pontos são discutidas.

Assessing potential production of maize using simulation models for land evaluation in Brazil

. The paper highlights the advantages of modelling to simulate dynamic processes and to couple environmental data more closely with effects on crops. The CERES-Maize crop model and the DSSAT software package were selected for the work and the region of the Triângulo Mineiro in the state of Minas Gerais was selected as the study area. The results showed that there are differences in the potential production of the Latosols of the Triângulo Mineiro and this should be taken into account when extrapolating or transferring technology for other regions within the same cerrado ecosystem of central-west Brazil. It is essential to improve the number of points with weather data collection since, as demonstrated for Frutal, the climate of the Triângulo can determine differences in potential agricultural production as well as risk for production. The study showed that the use of crop models can improve land suitability evaluations, for land use planning, or establishing strategies for rural funding.

Occurrence of magnetite in the sand fraction of an Oxisol in the Brazilian savanna ecosystem, developed from a magnetite-free lithology

It is relatively well established from many pedogenetic studies that, in deeply weathered Oxisols from Central Brazil, magnetite or maghemite are either inherited or transformed from magnetite of the mafic parent material. However, no similar pedogenetic pathways have been reported in the literature for other lithologies, such as limestone and pelitic rocks (shales and slates) of the Bambuí Group in Brazil. In these sedimentary, non-mafic lithologies, magnetic minerals are not likely to occur. Despite that, magnetic nodules were identified in a representative Oxisol pedon developed on this pedodomain, under savanna (Cerrado). Magnetic and non-magnetic fractions of nodules were separated with a hand magnet. Chemical and mineralogical compositions of these nodules were determined by conventional chemical methods, powder X-ray diffractometry (XRD), and 298 K Mössbauer spectroscopy. For the magnetic fraction, containing up to 84 dag/kg of Fe2O3 but also relatively rich in Al, Ti, Cr, and Si, Mössbauer measurements were also made at 4.2 K, without and with an externally applied magnetic field of 8 Tesla, and at 100 K. Mössbauer results and structural Rietveld refinement of the XRD data consistently suggest that the iron oxide mineralogy corresponds to approximately equivalent proportions of hematite and a partially oxidised magnetite, containing 3 dag/kg of iron as FeO. Laboratory tests were conducted in an attempt to produce magnetic material by heating this non-magnetic fraction. The sample was wrapped in filter paper and heated at 300°C for 30 min, and the results were compared with the naturally occurring magnetic nodules. The saturation magnetisation value of the thermally treated sample was found to be σ = 7 J/T.kg, well below σ = 16 J/T.kg of the magnetic soil nodules. Mössbauer and XRD results indicate that the iron oxide mineralogy of this laboratory-produced magnetic sample also corresponds to a mixture of partially oxidised magnetite and hematite. Two other parts of the same non-magnetic, naturally hematite-rich precursor were mixed with charcoal, to act as reducing agent, and oven-heated at 450°C and 600°C, respectively, for 1 h, producing increasing reduction of the hematite to magnetite. These laboratory simulations support the model in which magnetite in these hematite-rich nodules was formed under the influence of seasonal burning regimes of the covering vegetation, followed by partial re-conversion of the magnetite particles to hematite under long-term atmospheric exposure to air. This model is consistent with a long-term, seasonal fire history, assumed for the genesis of the Cerrado ecosystem in the Central Brazil, although a wider validity for the entire Bambuí Group area remains open.

Nesting biology, seasonality, and flower hosts of Epicharis nigrita (Friese, 1900) (Hymenoptera: Apidae: Centridini), with a comparative analysis for the genus

Nesting biology and foraging behaviour of Epicharis nigrita were studied in a cerrado ecosystem in São Paulo State, Brazil. Epicharis nigrita is a univoltine and seasonal bee species that collects pollen and floral oils from Byrsonima (Malpighiaceae) flowers. Activity of adults was observed on nesting sites and on flowers from October to December. Epicharis nigrita builds nests in aggregations in sandy soil. A nest consists of a single tunnel, which leads to a single urn-shaped cell. Cells are provisioned with a mixture of pollen and floral oils from Byrsonima. Cleptoparasitic species of the genera Rhathymus, Mesoplia, and Tetraonyx were active at the nesting sites. The biology of E. nigrita is compared to that of other species in the genus. Resumo A biologia da nidificação e o comportamento de forrageamento de Epicharis nigrita foram estudados em um ecossistema de cerrado no estado de São Paulo, Brasil. Epicharis nigrita é uma espécie de abelha univoltina e sazonal, que coleta pólen e óleos de flores de Byrsonima (Malpighiaceae). Atividade dos adultos foi observada na área de nidificação e nas flores entre outubro e dezembro. Epicharis nigrita constrói ninhos em agregações em solo arenoso. O ninho consiste de um único canal que leva a uma única célula isolada, com forma de urna. Células são aprovisionadas com uma mistura de pólen e óleos florais de Byrsonima. Espécies de cleptoparasitos dos gêneros Rhathymus, Mesoplia e Tetraonyx foram encontradas em atividade nas áreas de nidificação. A biologia de E. nigrita é comparada a de outras espécies no gênero.

Least limiting water range: A potential indicator of changes in near-surface soil physical quality after the conversion of Brazilian Savanna into pasture

The Brazilian savanna, or “Cerrado”, is an ecosystem that originally covered more than 200 Mha in Brazil. It is estimated that about 49.5 Mha in the Cerrado are now covered with cultivated pastures, which are responsible for half of Brazilian beef production. However, soil and pasture degradation represent a threat to this productive system and to the Cerrado ecosystem itself. Thus, the objective of this research was to evaluate the least limiting water range (LLWR) as an index of near-surface soil physical quality after conversion of Brazilian savanna to continuous and short-duration grazing systems. Three sites were evaluated: native Cerrado (NC), continuous grazing (CG), and short-duration grazing (SG). Thirty soil cores (5 cm height, 5 cm diameter) were collected at each site, and used for soil bulk density, soil water retention curve, and soil penetration resistance curve determinations. The results were used for quantification of LLWR and critical bulk density ( D bc), in which LLWR equals zero. The near-surface soil physical quality, as evaluated by the LLWR, was most restrictive for potential root growth in SG. In CG, potential restriction was moderate; however, the entire soil bulk density range was below the D bc. In NC, potential restriction was minimum. The soil structural degradation process was primarily related to the increase in stocking rates in the grazing systems. The LLWR proved to be a useful indicator of Cerrado soil physical quality, being sensitive to alterations in near-surface physical properties.