Drivers and assemblies of soil eukaryotic microbes among different soil habitat types in a semi-arid mountain in China.
Ontology highlight
ABSTRACT:
SUBMITTER: Zhao H
PROVIDER: S-EPMC6286657 | biostudies-literature | 2018
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Arbuscular mycorrhizal fungi (AMF) play an essential role in complex ecosystems. However, the species diversity and composition of AMF communities remain unclear in semi-arid mountains. Further, it is not well understood if the characteristics of AMF community assemblies differ for different habitat types, e.g., agricultural arable land, artificial forest land, natural grassland, and bush/wood land. Here, using the high-throughput technology by Illumina sequencing on the MiSeq platform, we explored the species diversity and composition of soil AMF communities among different habitat types in a semi-arid mountain (Taihang Mountain, Mid-western region of China). Then, we analyzed the effect of nutrient composition and soil texture on AMF community assembly. Our results showed that members of the Glomus genera were predominated in all soil types. The distance-based redundancy analysis indicated that the content of water, available phosphorus, and available potassium were the most crucial geochemical factors that significantly affected AMF communities (p < 0.05). The analysis of the soil texture confirmed that AMF diversity was negatively correlated with soil clay content. The comparison of AMF diversity among the various habitat types revealed that the artificial forest land had the lowest AMF diversity in comparison with other land types. Our findings suggest that there were differences in species diversity and composition of soil AMF communities among different habitat types. These findings shed new light on the characteristics of community structure and drivers of community assembly in AMF in semi-arid mountains, and point to the potential importance of different habitat types on AMF communities.
| S-EPMC5724403 | biostudies-literature
Project description:Soil microbial in arid and semi-arid ecosystem Raw sequence reads
| PRJNA1067364 | ENA
Project description:Soil microbial in arid and semi-arid ecosystem Raw sequence reads
| PRJNA883931 | ENA
Project description:An understanding of the habitat selection patterns by wild herbivores is critical for adaptive management, particularly towards ecosystem management and wildlife conservation in semi arid savanna ecosystems. We tested the following predictions: (i) surface water availability, habitat quality and human presence have a strong influence on the spatial distribution of wild herbivores in the dry season, (ii) habitat suitability for large herbivores would be higher compared to medium-sized herbivores in the dry season, and (iii) spatial extent of suitable habitats for wild herbivores will be different between years, i.e., 2006 and 2010, in Matetsi Safari Area, Zimbabwe. MaxEnt modeling was done to determine the habitat suitability of large herbivores and medium-sized herbivores. MaxEnt modeling of habitat suitability for large herbivores using the environmental variables was successful for the selected species in 2006 and 2010, except for elephant (Loxodonta africana) for the year 2010. Overall, large herbivores probability of occurrence was mostly influenced by distance from rivers. Distance from roads influenced much of the variability in the probability of occurrence of medium-sized herbivores. The overall predicted area for large and medium-sized herbivores was not different. Large herbivores may not necessarily utilize larger habitat patches over medium-sized herbivores due to the habitat homogenizing effect of water provisioning. Effect of surface water availability, proximity to riverine ecosystems and roads on habitat suitability of large and medium-sized herbivores in the dry season was highly variable thus could change from one year to another. We recommend adaptive management initiatives aimed at ensuring dynamic water supply in protected areas through temporal closure and or opening of water points to promote heterogeneity of wildlife habitats.
| S-EPMC5040439 | biostudies-literature
Project description:Indaziflam, a broad-spectrum, pre-emergence herbicide was the focus of a field investigation conducted after the identification of sporadic injury symptoms on the pecan trees a few months after the application. The study was conducted in two pecan orchards located in southern New Mexico, USA, and southeastern Arizona, USA. The objectives of this study were to evaluate the occurrence and distribution of indaziflam in the soil profile of areas where pecan trees were injured (impacted) and areas where no injury symptoms were observed (unimpacted), and to determine the relationship between indaziflam concentrations and soil properties in those locations. Soil samples were collected, one year after applications, from six depth representing 0-7, 7-15, 15-30, 30-60, 60-90 and 90-120 cm depth to determine the concentration of indaziflam in impacted and unimpacted areas of the two orchards. Soil samples were analyzed to determine texture, bulk density, organic matter content, cation exchange capacity, pH, nitrate, chloride and calcium concentrations. The detection frequency of indaziflam was higher in Arizona than in New Mexico, likely due to the differences between the tillage practices and sand contents of the orchards. No significant correlations were observed between indaziflam and soil properties, however indaziflam was mostly detected in areas where pecan trees were unimpacted probably as result of greater organic matter content and soil porosity. More research is needed to understand the causes of injury to pecan trees by indaziflam application.
| S-EPMC4423937 | biostudies-other
Project description:Leachate migration from open landfills is an environmental concern of developing cities. This study investigated the base soil-profile pedo-physical and chemical properties of the South African Sepane soil form or referred to as Cutanic Luvisol at the Bloemfontein southern landfill under the Mangaung municipality in the Free State Province. Six soil-profiles pedo-physical, exchangeable-cations and heavy metals concentrations were characterized from in-situ, core and loose soil-samples. The DTPA Test from a 5g air-dried soil extracted heavy metals. The soil profile was characterized by a layered Orthic-A, pedocutanic B- and C-horizons with lower horizons containing mean-total clay of 72%, bulk-density (≥1.5 gcm-3) and saturated hydraulic-conductivity (Ks < 6mmhr-1). Mean soil pH increased with depth from 6.4 to 6.8 along-side exchangeable-cations ranging from 19 to 2573 mgkg-1 in the order Ca > Mg > K > Na > S > P and Ca > Mg > Na > K > S > P for the respective A- and B-horizons. The Mg/K and (Ca + Mg)/K exceeded norm ratios. Soil-profile horizons had respective 44%, 34% and 22% heavy-metal distribution with mean content range of 0.001-37.3 mgkg-1 in the order Mn > Fe > Cr > Zn > Cu > As > Pb > Ni > Cd and Fe > Mn > Cr > Cu > As > Pb > Zn > Ni > Cd for the surface and subsurface horizons, respectively. Heavy-metal mean concentrations were below the norm except for Cr that was higher than 150% from upper horizons and posed serious risk to the near-surface environment. Soil profiles heavy-metal content and pollution-index was unpolluted (0.3-0.4), decreased with depth and reflected no subsurface pollution concerns. This study findings highlighted low internal-migration potential of clay soils and the need for understanding the sources and mode of migration of Cr at the landfill alongside continued monitoring.
| S-EPMC6806662 | biostudies-literature
Project description:BackgroundIn a context of long-term highly intensive grazing in grassland ecosystems, a better understanding of how quickly belowground biodiversity responds to grazing is required, especially for soil microbial diversity.MethodsIn this study, we conducted a grazing experiment which included the CK (no grazing with a fenced enclosure undisturbed by livestock), light and heavy grazing treatments in a desert steppe in Inner Mongolia, China. Microbial diversity and soil chemical properties (i.e., pH value, organic carbon, inorganic nitrogen (IN, NH4+-N and NO3--N), total carbon, nitrogen, phosphorus, and available phosphorus content) both in rhizosphere and non-rhizosphere soils were analyzed to explore the responses of microbial diversity to grazing intensity and the underlying mechanisms.ResultsThe results showed that heavy grazing only deceased bacterial diversity in the non-rhizosphere soil, but had no any significant effects on fungal diversity regardless of rhizosphere or non-rhizosphere soils. Bacterial diversity in the rhizosphere soil was higher than that of non-rhizosphere soil only in the heavy grazing treatment. Also, heavy grazing significantly increased soil pH value but deceased NH4+-N and available phosphorus in the non-rhizosphere soil. Spearman correlation analysis showed that soil pH value was significantly negatively correlated with the bacterial diversity in the non-rhizosphere soil. Combined, our results suggest that heavy grazing decreased soil bacterial diversity in the non-rhizosphere soil by increasing soil pH value, which may be due to the accumulation of dung and urine from livestock. Our results highlight that soil pH value may be the main factor driving soil microbial diversity in grazing ecosystems, and these results can provide scientific basis for grassland management and ecological restoration in arid and semi-arid area.
| S-EPMC10924786 | biostudies-literature
Project description:Fertilization can significantly affect the quality of crop and soil. To determine the effects of long-term fertilization on crop yield and carbon:nitrogen:phosphorus (C:N:P) stoichiometry in soil, a study was conducted on the terraced fields of the Loess Plateau from 2007 to 2019. Nine fertilization treatments were included: no fertilizer; organic fertilizer (O); organic and nitrogen fertilizers (ON); organic, nitrogen, and phosphorus fertilizers (ONP); organic and phosphorus fertilizers (OP); phosphorus and nitrogen fertilizers; potash and nitrogen fertilizers; potash, nitrogen, and phosphorus fertilizers; and potash and phosphorus fertilizers. Under these treatments except for CK and PK, crop yields initially decreased but later increased. The nutrient content and C:N:P stoichiometry increased in soil depth of 0-20 cm. The soil available nutrients did not change significantly with the duration of fertilization. The O, ON, ONP, and OP had the most evident effect on the enhancement of soil nutrient content, whereas O and ON had the most evident effect on the increase in soil organic carbon (SOC):total phosphorus (TP) and total nitrogen (TN):TP. In soil depth of 0-20 cm, crop yield, SOC:TN, SOC:TN, SOC:TP, and TN:TP significantly correlated with soil nutrients. This study indicated that long-term fertilization can effectively improve crop yield, soil fertility, and soil C:N:P stoichiometry. Meanwhile, the single application of an organic fertilizer or the combination of organic and nitrogen fertilizers can improve the condition of nitrogen limitation in arid and semi-arid areas.
| S-EPMC8072689 | biostudies-literature
Project description:Herbivory is a major fitness pressure for plants and a key driver of crop losses in agroecosystems. Dense monocultures are expected to favor specialist herbivorous insects, particularly those who primarily consume crop species; yet, levels and types of herbivory are not uniform within regional cropping systems. It is essential to determine which local and regional ecological factors drive variation in herbivory in order to support functional agroecosystems that rely less on chemical inputs. Crops in the genus Cucurbita host a suite of both generalist and specialist herbivores that inflict significant damage, yet little is known about the relative contribution of these herbivores to variation in herbivory and how local- and landscape-scale Cucurbita resource concentrations, management practices, and natural enemies mediate this relationship. In this study, we tested whether three foundational ecological hypotheses influenced Cucurbita herbivory across 20 pumpkin fields in the semi-arid Southern High Plains Region of Texas. We used generalized linear mixed models and confirmatory path analysis to assess whether the Density-dependent Herbivory Hypothesis, Resource Concentration Hypothesis, or the Natural Enemies Hypothesis, could explain variation in Cucurbita herbivory and insect dynamics in the context of conventional agronomic practices. We found that herbivory increased over time, indicating that herbivores were causing sustained damage throughout the growing season. We also found that fields with higher local Cucurbita resources had lower herbivory, suggesting a resource dilution effect. Natural enemy communities were more abundant and taxonomically rich in sites with greater generalist herbivore abundance, though predator abundance declined over time, indicating that late-season crop fields are most at risk given high herbivory and low natural enemy-based control. Our findings also suggest that while local resource availability may drive the abundance and richness of arthropod communities, additional agronomic and phenological information is needed to anticipate herbivory risk in an agriculturally dominated landscape.
| S-EPMC11233904 | biostudies-literature
Project description:Comprehension of whether human and livestock presence affects wildlife activity is a prerequisite for the planning and management of humans and livestock in protected areas. Xinglong Mountain Nature Reserve (XMNNR) in northwest China, as a green island in a semi-arid mountain ecosystem, is one of the scattered and isolated areas for Alpine musk deer (AMD), an endangered species. AMD cohabits their latent habitat area with foraging livestock and humans. Hence, habitat management within and outside the distribution areas is crucial for the effective conservation of AMD. We applied camera traps to a dataset of 2 years (September 2018-August 2020) to explore seasonal activity patterns and habitat use and assess the impacts of AMD habits in XMNNR. We investigated AMD responses to livestock grazing and human activities and provided effective strategies for AMD conservation. We applied MaxENT modeling to predict the distribution size under current conditions. The activity patterns of the AMD vary among seasons. The optimum habitat average distance to cultivated land ranges of AMD (150~3300 m during grass period/100~3200 m during withered grass period), distances to the residential area ranges (500~5700 m during the grass period/1000~5300 m during the withered grass period), elevation ranges (2350~3400 m during the grass period/2360~3170 m during the withered grass period), aspect ranges (0~50° and 270~360°), normalized vegetation index ranges (0.64~0.72 during the grass period/0.14~0.60 during the withered grass period), and land cover types (forest, shrub, and grassland). Results present that the predicted distributions of AMD were not confined to the areas reported but also covered other potential areas. The results provide evidence of strong spatial-temporal avoidance of AMD in livestock, but gradually adjusting to human activities. These camera trap datasets may open new opportunities for species conservation in much wider tracts, such as human-dominated landscapes, and may offer guidance and mitigate impacts from livestock, as well as increase artificial forest planting and strengthen the investigation of the potential population resources of AMD.
| S-EPMC9658949 | biostudies-literature