Abstract Background and Aims Renal osteodystrophy is highly prevalent among people with chronic kidney disease (CKD). We recently showed that inulin, a prebiotic fermentable dietary fiber, improved ...cortical bone parameters in rats with moderate-to-severe CKD. Our objective was to evaluate if this effect was unique to the prebiotic fibers or if other fiber properties, such as viscosity, could be beneficial to bone in a rat model of CKD-mineral and bone disorder (CKD-MBD). Method 22-week-old Cy/+ male rats (50% kidney function compared to normal; CKD hereafter) were randomly assigned to receive one of four fiber treatments (10% w/w each) based on fermentability and viscosity: 1) Cellulose (−fermentability, −viscosity), 2) Inulin (+fermentability, −viscosity), 3) Psyllium husk (−fermentability, +viscosity), or 4) Pectin (+ fermentability, +viscosity). These diets were formulated with a semi-purified, casein-based background diet with 0.7% calcium and 0.7% phosphorus. Treatments lasted 10 weeks, and rats were euthanized at 32 weeks of age (kidney failure; ∼15% of normal). Micro-computed tomography (μCT) at 12-μm resolution was performed on the proximal tibia. Serum creatinine, plasma phosphorus, and plasma calcium were analyzed using colorimetric assays. One-way ANOVA was used to test the effect of dietary fiber types on outcome measures. Results At 32 weeks of age, serum creatinine was lower in the inulin, psyllium, and pectin-treated CKD rats (<0.04). Plasma calcium concentrations were similar between treatments, but phosphorus was lower in the psyllium and pectin-treated CKD rats (p < 0.02). Bone cortical area was higher in the inulin and psyllium-treated CKD rats compared to cellulose-treated rats (p < 0.007). Cortical thickness was higher in the inulin, psyllium, and pectin-treated CKD rats compared to cellulose-treated rats (p < 0.02). There was less cortical porosity in the inulin, psyllium, and pectin-treated rats (p < 0.02). Fermentable or viscous fibers did not impact trabecular bone volume, thickness, spacing, and number (p < 0.05). Plasma phosphorus was negatively associated with cortical area (r = −0.56; p < 0.0001) and cortical thickness (r = −0.75; p < 0.0001), and positively associated with cortical porosity (r = 0.74; p < 0.0001). Conclusion Fermentable and viscous fibers improved cortical bone but had no effect on trabecular bone. This effect may be, at least in part, due to the fiber's ability to lower plasma phosphorus and likely parathyroid hormone.
Green water is primarily associated with the appearance of annual plants and plays a significant role in biomass production in both arid and semi-arid ecosystems. Herein, we aim to estimate the ...optimal threshold for determining the presence or absence of annual plants and use them as an ecological indicator to assess potential green water areas in Kuwait as a case study. We integrate remote sensing techniques and MaxEnt modeling. The AUC for the annual plant distribution with all examined factors is 0.847, and the standard deviation is 0.050. The results demonstrated that potential locations with high levels of green water cover <20% of the country. The annual plant distribution was significantly correlated with several types of perennial plants, maximum temperature, precipitation, and sandy soils. It was also found that annual plants are controlled by the spring and winter temperature decline and the timing of precipitation occurrence, especially the pattern and amount of rainfall received in November. Sandy loam and loam soils were found to be ideal for annual plants, although land depressions and soil types are crucial factors in determining annual plant distribution. Additionally, annual plants enhanced the growth of several perennial communities. To reiterate, our study's model helped to comprehend the significance of annual plants as an ecological indicator in sustaining soil moisture over a prolonged period, as well as factors controlling the distribution of annual plants. The developed model and indicators could support decision-makers in determining appropriate locations with adequate levels of green water for revegetation planning in arid landscapes.
•The distribution of annual plants, suitable soils, and green water are significantly interconnected.•Machine learning techniques are useful for selecting suitable locations for revegetation.•Revegetation of native plants could help grazing pastures to enhance food security.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•First study to investigate forest growth using multi-temporal terrestrial lidar data.•Estimation of tree level aboveground biomass using innovative methods.•Investigation of different conceptual ...approaches for estimating biomass change.•Results will benefit researchers to improve biomass change modeling with high accuracy.
Above ground biomass (AGB) is a crucial ecological variable and has to be accurately estimated to understand potential changes of the climate system and to reduce uncertainties in the estimates of forest carbon budget. The overall goal of this research is to estimate tree level AGB change using multi-temporal terrestrial laser scanning (TLS) datasets for trees in East Texas. Specific objectives are to (1) develop models using TLS parameters to estimate tree level AGB; and (2) investigate different conceptual approaches for estimating AGB change. Since majority of the AGB estimation models are developed only using diameter at breast height (DBH), we investigated the potential of TLS by extracting various geometric and statistical parameters for tree level AGB estimation. National and regional level AGB estimation models were developed for loblolly pines. To estimate the change in AGB, three different approaches were followed. The best AGB estimation model for loblolly pines had DBH, height variance, and interquartile distance as independent variables. The best AGB estimation model for hardwoods included volume and crown width as independent variables. For AGB change of loblolly pines, direct modeling of AGB change with TLS data available for 2009 and 2012 provided the best results. An extensive literature review reveals that this is the first study to model the change in AGB using different innovative and conceptual approaches with multi-temporal TLS data. The results of our study indicate the capability of TLS to model the change in tree level AGB, with potential for reducing the amount of field work when using multi-temporal terrestrial TLS datasets. We believe that the results of this study will benefit forest management and planners for prudent decision making, and other remote sensing studies from airborne and spaceborne platforms, for map upscaling, data fusion, or calibration purposes.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
This study focused on evaluating factors influencing the growth of perennial shrubs by integrating field-based experiments and spatial analysis using unmanned aerial vehicles (UAVs) to identify ...ecological indicators that can help detect potential locations for restoration and revegetation of native plants. The experiment was implemented in the Al-Abduli protected area in Kuwait, which is mainly dominated by a Rhanterium epapposum community (desert shrub). Aerial imagery of the study site was acquired using UAVs during the growing season to estimate the desert shrub biomass and carbon stock. Then, soil samples were collected based on vegetation density to determine the impact of the soil's physical and chemical properties on vegetation biomass, growth, and distribution. It was found that shrub biomass was significantly correlated with crown area and shrub volume. We also observed that annual plants support the growth of perennial shrubs, as the mean shrub height and crown area (CA) are significantly higher, with averages of 0.7 m and 3 cm, respectively, in the presence of high annual plant density. However, shrubs in plots with low annual density had an average shrub height of 0.5 m and CA of 1.4 cm. Annual plants also enhance the soil by providing approximately 50% higher soil moisture, phosphorous (P), organic matter (OM), and carbon dioxide (CO2) sequestration. In addition, annual plants are mainly supported by loamy soils in the deeper soil layers. We concluded that locations covered with annual plants represent suitable soils and that this can be considered a biological indicator for convenient locations for restoration and revegetation of native perennial shrubs. Remote sensing technologies could be utilized for initial assessments to detect sites that may support annual plant growth over a large scale for classification as potential restoration and revegetation areas.
•Unmanned Aerial Vehicles (UAVs) is a powerful technology used to measure desert shrub biomass.•Shrub size and density are associated with the high annual plant surrounding the shrub areas.•Annual plants play a significant role in enhancing the soil properties.•Annual plants can be used as a biological indicator of suitable revegetation sites.•More attention needs to be given to annual plants in restoration and revegetation planning.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
