Jack beans and vetiver grass growth on iron ore tailing sediments from the Doce River dam disaster in Brazil: plant growth regulator effects under different edaphic conditions

Journal of Soils and Sediments - After the greatest environmental disaster in the history of Brazil and the deposition of the iron ore tailings in alluvial regions, the process of revegetation for...     

Fertilization rate,motility, lipid peroxidation and pH changes after chilled storage of rainbow trout (Oncorhynchus mykiss) eggs and spermatozoa by a RMPI medium

The aim of this study was to evaluate the effects of Roswell Park Memorial Institute (RPMI) 1,640 medium on chilled storage of eggs and spermatozoa of rainbow trout (Oncorhynchus mykiss). After 3 days of storage, eggs in RPMI 1,640 media (pH 8.2, 9 and 10), Cortland medium and coelomic fluid were inseminated with fresh spermatozoa (Experiment 1). Eggs in RPMI 1,640 medium at pH 8.2 shown the lowest thiobarbituric acid‐reactive substances (TBARS, 0.053 ± 0.003 nmol/ml) and pH changes (from 8.20 ± 0.01 to 8.18 ± 0.01), the highest fertilization rate (82 ± 3%). Undiluted and diluted spermatozoa at ratios of 1:2 and 1:9 with RPMI 1,640 media (pH 8.2, 9 and 10) and Cortland medium were inseminated with fresh eggs (Experiment 2). Spermatozoa in RPMI 1,640 medium at pH 9 (1:9) caused the lowest TBARS content (0.037 ± 0.002 nmol/ml) and pH changes (from 9.00 ± 0.01 to 8.98 ± 0.01), the highest fertilization rate (77 ± 2%) and motility parameters. Based on Experiments 1 and 2, eggs and spermatozoa were stored for another 3 days in RPMI 1,640 medium at pH 8.2 and 9 (1:9) respectively (Experiment 3). Fertilization rate of storage eggs and spermatozoa in Experiment 3 was 79 ± 5%, showing successfully storage of rainbow trout gametes with the same medium.     

A primer of acoustic analysis for landscape ecologists

In this paper we present an introduction to the physical characteristics of sound, basic recording principles as well as several ways to analyze digital sound files using spectrogram analysis. This paper is designed to be a “primer” which we hope will encourage landscape ecologists to study soundscapes. This primer uses data from a long-term study that are analyzed using common software tools. The paper presents these analyses as exercises. Spectrogram analyses are presented here introducing indices familiar to ecologists (e.g., Shannon’s diversity, evenness, dominance) and GIS experts (patch analysis). A supplemental online tutorial provides detailed instructions with step by step directions for these exercises. We discuss specific terms when working with digital sound analysis, comment on the state of the art in acoustic analysis and present recommendations for future research.     

Histology of corpuscles of Stannius in Lake Van fish (Alburnus tarichi Güldenstädt, 1814) (Cyprinidae)

In the present study, the location, histology and number of corpuscles of Stannius (Sc), which are endocrine glands associated with the kidneys of teleost fish, were investigated for the first time in Lake Van fish (Alburnus tarichi), an anadromous and endemic inhabiting Turkey's Lake Van Basin. The Sc, which were ovoid or spheroid and white or cream in colour, were found to vary in number between three and five among the examined fish. The glands were located in the caudal part of the kidney, and either partially or completely embedded, and found to be present on both the ventral and dorsal surface of either side of the caudal part of the kidney. The Sc were surrounded by a connective tissue capsule that penetrated and divided the gland into incomplete lobules. Two types of cells were determined in the parenchyma of the gland. Type-I cells were predominant throughout the parenchyma and larger than the second (type-II). In the type-I cells, the cytoplasm was observed as weakly or moderately eosinophilic with haematoxylin and eosin staining and weakly or moderately acidophilic with Mallory's triple staining. In the type-I cells, the cytoplasm exhibited weak to moderate periodic acid-Schiff staining and slight or uniform staining with aldehyde fuchsin. The type-II cells were round, had a darkly stained spherical nucleus and were dispersed among the type-I cells. They displayed no cytoplasmic staining with the abovementioned stains.     

Dynamics of natural bovine herpesvirus-1 (BoHV-1) infection in a dairy herd

In this study, natural cycling of BoHV-1 infection was investigated in two groups of dairy cattle containing 2120 head. Group 1 comprised 127 animals and they were monitored for BoHV-1 infection virologically and serologically in six consecutive sampling periods. It consisted of naive heifers between 6 and 8 months of age, while in group 2, age, sex and the BoHV-1 serostatus of the animals were disregarded. The animals in group 1 were found to have seroconverted at the second sampling. Results of the serological study showed slight antibody response after natural BoHV-1 infection in the herd and neutralizing titres fell below protective levels in the 6–8 months after the peak. During the 2-year study period, one recurrence was detected after primary infection. Virus isolation studies revealed a cytopathic effect indicative of BoHV-1 in two nasal swabs taken during the fifth sampling period from animals with mild upper respiratory tract symptoms. As the study was carried out under natural conditions, it is not known whether the viruses isolated were from recurrences or re-infections. Data from cross-neutralization tests with herd isolates showed higher antibody response than those with the reference virus. The dynamics of BoHV-1 in both groups were found to be statistically similar.     

Modeling acoustic diversity using soundscape recordings and LIDAR-derived metrics of vertical forest structure in a neotropical rainforest

We determined the relationship between acoustic diversity and metrics of vertical forest structure derived from light detection and ranging (LIDAR) data in a neotropical rainforest in Costa Rica. We then used the LIDAR-derived metrics to predict acoustic diversity across the forest landscape. Sound recordings were obtained from 14 sites for six consecutive days during dusk chorus (6?pm). Acoustic diversity was calculated for each day as the total intensity across acoustic frequency bands using the Shannon index and then averaged over the 6?days at each site. A 10?m radius around each site was used to obtain several LIDAR-derived metrics describing the vertical structural attributes of the forest canopy. Multiple linear regression (MLR) with Akaike information criterion was used to determine a top-ranked model with acoustic diversity as the dependent variable and the LIDAR metrics as independent variables. Acoustic diversity was modeled for forested areas (where canopy height was?>20?m) at 20?m resolution using coefficients obtained from the MLR, and a hotspot analysis was conducted on the resulting layer. Acoustic diversity was strongly correlated (R ² ?=?0.75) with the LIDAR metrics suggesting that LIDAR-derived metrics can be used to determine canopy structural attributes important to vocal fauna species. The hotspot analysis revealed that the spatial distribution of these canopy structural attributes across the La Selva forest is not random. Our approach can be used to identify forest patches of potentially high acoustic diversity for conservation or management purposes.     

Regional inflation persistence in Turkey

The purpose of the current study is to investigate the degree of inflation persistence, its geographical variation, sources of cross‐regional variation, and presence of geographical/sectoral aggregation bias in national monetary policy. Our data set covers 26 NUTS‐2 level Turkish regions and monthly CPI inflation over the period 2003–2019. We first estimate the degree of regional inflation persistence by autoregressive regressions, check its robustness against the presence of structural breaks (by Bai–Perron's algorithm) and nonlinearities (by Markovian Regime Switching regressions). Second, we examine the possibility of geographical and sectoral aggregation bias. Third, we investigate the cross‐regional determinants of inflation persistence by panel data analysis, employing hybrid‐effects spatial panel regressions. We analyze the direct and indirect effects of the determinants and test for regional spillover effects. Three main results are obtained. First, estimated persistence degrees are heterogeneous across regions. The geographical pattern is empirically robust against structural breaks and nonlinearities. We find that inflation persistence is distributed in a spatially correlated manner. Second, when sectoral and regional aggregation bias is tested, only sectoral aggregation indicates a considerable level of bias. Third, we find that the presence of large firms in the region and a higher share of agricultural output in GDP leads to lower persistence, while an increased share of industrial output, and increased trade volume leads to higher inflation persistence. Moreover, we find spatial spillovers of price variability evident in regression analysis. From a policy standpoint, it is required that structural policy programs are targeted to maintain flexibility in the regions where persistence is high (i.e., providing market entry/exit, institutional quality, policy credibility, stimulation of SMEs). Moreover, sectors that have high persistence, such as Hotels and Restaurants (persistence degree 0.55) and Health Services (0.39) should be weighted more in CPI calculations.     

Impacts of increased fire frequency and aridity on eucalypt forest structure,biomass and composition in southwest Australia

Water stress and fire disturbance can directly impact stand structure, biomass and composition by causing mortality and influencing competitive interactions among trees. However, open eucalypt forests of southwest Australia are highly resilient to fire and drought and may respond differently to increased fire frequency and aridity than forests dominated by non-eucalypt species. We measured the variation in stem density, basal area, stand biomass, sapwood area, leaf area and litterfall across 16 mixed jarrah (Eucalyptus marginata) and marri (Corymbia calophylla) forest stands along an aridity gradient in southwest Australia that had variable fire histories. Fire frequency was defined as the total number of fires over a ∼30-year period and aridity as the ratio of potential evapotranspiration to annual precipitation. Total stand biomass and sapwood area were predicted from diameter at breast height of individual jarrah and marri trees using allometric equations. Leaf area was estimated using digital cover photography. More arid and frequently burnt stands had higher stem density, especially of smaller trees, which were mainly jarrah. Overall, both standing biomass and leaf area decreased at more arid sites, while sapwood area was largely unaffected by aridity, suggesting that these stands respond to increased water limitation by decreasing their leaf area relative to their sapwood area. Biomass of marri was reduced at more arid and, to a lesser extent, at more frequently burnt stands. However, total stand biomass (jarrah and marri) and leaf area index did not vary with fire frequency, suggesting that less marri biomass (due to slower growth rates, higher mortality or less recruitment) was compensated by an increase in the density of jarrah trees (regeneration). We conclude that increased fire and drought shift tree species composition towards more fire-resistant species and result in denser stands of smaller trees. In contrast, total stand biomass declines with increasing aridity, but has no association with fire frequency.     

Unravelling zinc and lead distributions in dolomitic and metapelitic soils of the Brazilian Central Plateau: insight from physical fractionation,optical microscopy and X‐ray microfluorescence

Large zinc and lead concentrations occur in strongly weathered soils of Cambisol–Ferralsol toposequences in the Paracatu‐Vazante area (Central Plateau, Brazil). Weathering of the mineralized dolomite parent material of the Cambisols is hypothesized to be the geogenic source of zinc (Zn) and lead (Pb), with dissemination downslope into the Ferralsols. This leads to different metal distribution patterns in the two soils. We studied Zn and Pb distributions in selected A and B horizons of two typical profiles to examine this hypothesis and assess the contribution of sesquioxides to the retention of these metals. Physical separation into 200–2000, 50–200, 20–50 and < 20‐µm size fractions in water without chemical dispersants was carried out before (F1) and after (F2) ultrasonification. The fractions were analysed for total and extractable Zn and Pb concentrations and studied by X‐ray diffraction and optical microscopy. Microscale Zn and Pb distribution maps were obtained by using micro‐X‐ray fluorescence on thin sections. For the Cambisol, the composition, morphology and large Zn and Pb concentrations of coarse‐sized F2 fractions were consistent with a geogenic metal origin. In both soils, < 20‐µm fractions contained the largest amounts of Zn and Pb. In the Cambisol, this < 20‐µm fraction included poorly crystalline Mn‐rich material, encouraging strong Pb sorption. The Ferralsol < 20‐µm fractions contained more Al‐ and Fe‐oxide‐rich microaggregates, which also enhanced strong metal retention. Large sesquioxide contents in these and similar tropical soils reduce metal mobilities. This limits the risk of toxicity when such soils, with metal contents exceeding guidelines, are used for agriculture.