Miracle-dz/UniFAR-FTUs huggingface dataset:
Community response to removals of plant functional groups and species from a Chihuahuan Desert shrubland

Arid and semi-arid ecosystems often exhibit diverse plant growth forms in water-limited environments, but it is unclear whether resource competition (interference) is actually important in structuring communities. We chose a diverse Chihuahuan desert shrubland to examine the response of the plant community to experimental removals of selected perennial plant species or groups of species. Four treatments involved the removal of all individuals of all species of a single functional group (functional group removals: shrub removal, succulent removal, subshrub removal, perennial grass removal). Three other treatments involved removing species within functional groups. These seven treatments plus a control (no plants removed) were replicated six times each in 25 x25 m experimental plots, in summer 1995. Permanent belt transects were surveyed for number and sizes of all vascular plants in spring and fall in 1997, 1999, 2000, and 2001. Those plots from which the dominant shrub, Larrea tridentata, was removed had not recovered in total plant cover or volume by 2001, but cover and volume in all other treatments were similar to those in control plots. Relatively few species demonstrated a positive response to the removal of other species or functional groups. The perennial grass group and forbs were the most responsive; perennial grass cover increased in the shrub removal treatment relative to the control but treatment differences diminished after dry growing seasons in 2000 and 2001. Results over the first five years suggest that either environmental conditions or intrinsic biological characteristics limit the ability of most plant species to respond to the removal of substantial fractions of community biomass and composition in the short term. Such slow response by both dominant and less abundant components of the community has implications for the recovery of semi-arid systems after human disturbance or other events leading to the reduction of biological diversity.
Effects of soil types and enhanced nutrient levels on the productivity of earthworm (eudrilius eugeniae, kinberg)

The productivity, in terms of ability to reproduce, of the earthworm Eudrilius eugeniae (Kinberg), was studied in the laboratory under three (sandy, loamy and clayey) soil conditions with and without cow dung enrichment, in order to determine their individual suitability for the culture and breeding of the species. Ten earthworms of equal sizes were each introduced into two groups of twelve pots, each subdivided into three groups of four pots each, containing 9500g of ordinary sandy, loamy or clayey soils (served as control), and 300g cow dung enriched sandy, loamy and clayey soils (served as experimental). Experimental and control pots were moistened with 750cm3 of water every three days for ten weeks. Both sets of pots were assessed for total earthworm population, their weights and lengths. Percentage increases in earthworm population in the control soil media were 72.5%, 92.5% and 170% in clayey, sandy and loamy soils respectively. Experimental pots yielded 560%, 1700% and 3395% increments in earthworm population for clayey, sandy and loamy soils respectively. Population increments amongst the three soil media differed significantly (P<0.05). Nutrient enriched soils produced significantly higher earthworm population than ordinary soils (P<0.05). The study shows superiority of loamy and nutrient enhanced soil in enhancing earthworm productivity.
Perturbation and Recovery Patterns of Starfish-Dominated Intertidal Assemblages in Chile, New Zealand, and Washington State

When starfish are removed from small portions (<63-m2 areas) of certain marine communities, mussels increase the percentage of space that they occupy. When compared to other studies in New Zealand and Washington State, new results from Chile indicate that none of these assemblages is stable when perturbed in this fashion. That is, all attain a different state within relatively brief periods. When starfish were permitted to return, we observed two different recovery patterns. In Chile, the experimental site converged rapidly toward the undisturbed control; at the other sites, mussels too large to be eaten by starfish continued to dominate the space. The results indicate the importance of size escapes from predation for marine communities. Whether these persistent, but diminishing in spatial coverage, stands of mussels are alternative stable states or not is dependent on the definition of stability employed.
Sprinkler Irrigation Changes Maize Canopy Microclimate and Crop Water Status, Transpiration, and Temperature

During a sprinkler irrigation event some water is lost due to wind drift and evaporation (WDEL). After the irrigation event, plant-intercepted water is lost due to evaporation. The water lost causes microclimatic changes which could result in positive or negative plant physiological changes. We studied the microclimatic and physiological changes on two fields grown with maize (Zea mays L.) irrigated with a solid-set sprinkler system. The temperature and vapor pressure deficit (VPD) of the air were measured at the crop canopy level and above and below the canopy. Changes in maize canopy temperature, transpiration, and leaf water potential (LWP) were determined. Sprinkler irrigation during daytime strongly modified the microclimate where plants grow during the irrigation time and for a short period after the irrigation event finished. Daytime irrigation decreased air temperature by 3.3 to 4.4°C and VPD by 1.0 to 1.2 kPa at 0.5 m below the crop canopy height. The decrease was lower as the measurement height increased. Microclimatic changes during nighttime irrigation were minimal. Daytime irrigation reduced maize canopy temperature by 4 to 6°C and plant transpiration by 58%, and increased LWP from ―1.2 and ―1.4 MPa to ―0.54 MPa. Transpiration reduction must be considered positive because it supposes a reduction of WDEL. The decrease in maize canopy temperature could be positive or negative, but the increase in LWP is a positive effect.
Cytomixis in Thinopyrum intermedium, Thinopyrum ponticum and its Hybrids with Wheat

Cytomixis has been described in many plant species, but not in Thinopyrum . The present study reports spontaneous cytomixis during microsporogenesis in Thinopyrum intermedium (2n = 42), Thinopyrum ponticum (2n = 70), and their F 1 hybrids with wheat. Cytomixis frequently occurred in early prophase I but very rarely in meiosis II. The type of cytomixis that occurred most often was where chromatins migrate from one nucleus into an adjacent cel1. Migration from one nucleus into two or more cells or from two or more nuclei into one cel1 was also observed. After a donor cell transferred chromatin to a recipient cell, the recipient cell would sometimes pass the chromatin on to another cell. Migration did not necessarily occur between cells in the same stage. Cytomixis in Th. ponticum and its hybrids with wheat was more complex than that in Th. intermedium . The possible causes, cytological consequences and genetic significance of cytomixis are discussed.
Contrasting seasonal modulation of the stress response in male and female rainbow trout

Between June and September the magnitude of the plasma cortisol response of maturing male and female rainbow trout to confinement was indistinguishable. A progressive increase in confinement-induced cortisol levels in both sexes occurred during the period May to September, associated with the seasonal rise in water temperature. Between September and January there was a more than 50% reduction in the magnitude of the cortisol response to confinement in male fish which coincided with declining water temperature and significant increases in plasma 11-ketotestosterone and elevated plasma testosterone levels. In contrast, female trout showed no evidence of a decline in cortisol responsiveness to confinement during the period September to January. Plasma estradiol-17β levels were significantly greater in females than males throughout the study period and this difference was maximal between September and January. However, plasma testosterone was also elevated in females during this period and levels overall were higher than those in male fish. Previous studies have shown estradiol-17β and testosterone to have diametrically opposed effects on stress responsiveness in trout, with the former enhancing, and the latter suppressing, the cortisol response to a stressor. The relative roles of androgens, estrogen and water temperature in modulating the stress responsiveness of rainbow trout is discussed.
Dueling Posterior Sampling for Interactive Preference-Based Learning

Ellen R. Novoseller1, Maegan Tucker2, Yibing Wei1, Yanan Sui3, Aaron D. Ames2, Yisong Yue1, Joel W. Burdick1, 2 1 Department of Computing and Mathematical Sciences, California Institute of Technology, {enovoseller, ywwei, yyue}@caltech.edu; jwb@robotics.caltech.edu 2 Department of Mechanical and Civil Engineering, California Institute of Technology, {mtucker, ames}@caltech.edu 3 School of Aerospace Engineering, Tsinghua University, ysui@tsinghua.edu. cn
The Impact of Fish Exclusion on the Abundance and Species Composition of Larval Odonates: Results of Short-Term Experiments in a North Carolina Farm Pond

Under natural conditions in a man-made North Carolina farm pond, a single small species, Perithelnis tenera, numerically dominates a littoral assemblage of larval dragonflies. Censuses of exuvia of larvae metamorphosing from the pond in three successive years demonstrated a consistent negative correlation between numerical dominance in the assemblage and species-specific size in the final larval instar. This pattern suggested that size-dependent processes, such as vertebrate predation, might structure the odonate assemblage. Exclusion of vertebrate predators from patches of emergent vegetation by screen enclosures for 3 mo increased total abundances of larval odonates by an order of magnitude. Dominance shifted from small species to species of intermediate size, especially Pach'dipl/a lo/ngipenllis. where fish were excluded. The largest species remained rare and were unaffected by fish exclusion. Four odonate species were facultatively multivoltine, completing larval development within 1-2 mo after coloni- zation of the fish enclosures. Fish exclusion also increased the abundance of large microcrustacea, especially the cladoceran Sitnocephalus serrulatuis. Large microcrustacea increased in abundance despite a corresponding increase in the abundance of their macroinvertebrate predators, where fish were excluded. The usual dominance of small Perithelnis in this assemblage was a probable consequence of differentially heavy predation by fish on moderate-sized species, and the unexplained failure of large species to recruit well under experimental or natural conditions. These results support the general importance of predation in structuring freshwater communities and document an important mode of population regulation operating during the aquatic larval phase of the odonate complex life cycle.
PERIPHYTIC DIATOM ASSEMBLAGES FROM BATHURST ISLAND, NUNAVUT, CANADIAN HIGH ARCTIC: AN EXAMINATION OF COMMUNITY RELATIONSHIPS AND HABITAT PREFERENCES

Diatoms are potentially the most important biomonitors of environmental change in high arctic lakes and ponds, but to date few autecological data are available. Because of the shallow nature of many of these water bodies, a large proportion of taxa are periphytic and planktonic diatoms are absent for the most part. By determining the microhabitat and substrate preferences of these benthic diatom taxa, the potential exists to infer past changes in available habitats from fossil diatom assemblages collected from sediment cores and ultimately to reconstruct past environmental and climatic changes responsible for these shifts in habitat availability. To refine our understanding of high arctic diatom habitat preference, the common diatom taxa found on submerged moss (bryophyte), sediment, and rock substrates from lakes and ponds on Bathurst Island, Nunavut, Canadian High Arctic were examined. The relationships among key limnological variables and the common taxa from each habitat were examined. Many diatom taxa exhibited varying degrees of microhabitat preference, with moss representing the more unique habitat. In addition, the following limnological variables significantly (P≤ 0.05) explained the species variance for each of the three substrates: Na+ and total nitrogen for moss; total phosphorus (filtered) and pH for rock; and Fe3+, total phosphorus (unfiltered), total nitrogen, temperature, and pH for sediment. These data can be used to help interpret monitoring and paleolimnological studies in this environmentally sensitive region.
Changes in the physiology and feed quality of cocksfoot (Dactylis glomerata L.) during regrowth

A glasshouse study was undertaken to determine the physiological and morphological changes in cocksfoot (Dactylis glomerata L.) during regrowth after defoliation. Individual plants were arranged in a mini-sward in a randomized complete block design. Treatments involved harvesting each time one new leaf had expanded (one-leaf stage), up to the six-leaf stage, with the plants separated into leaf, stubble (tiller bases) and roots. Stubble and root water-soluble carbohydrate (WSC), stubble and leaf dry matter (DM), tiller number per plant and leaf quality (crude protein (CP), estimated metabolizable energy (ME) and mineral content) were measured to develop optimal defoliation management of cocksfoot-based pastures. WSC concentration in stubble and roots was highest at the five- and six-leaf stages. Mean WSC concentration (g kg-1 DM) was greater in stubble than roots (32.7 ± 5.9 vs. 9.4 ± 1.5 respectively). There was a strong positive linear relationship between plant WSC concentration and leaf DM, root DM and tillers per plant after defoliation (Adj R2 = 0.72, 0.88 and 0.95 respectively). Root DM plant-1 and tiller DM tiller-1 decreased immediately following defoliation and remained low until the three-leaf stage, then increased from the four-leaf stage. Tillers per plant remained stable until the four-leaf stage, after which they increased (from 9.9 ± 0.5 to 15.7 ± 1.0 tillers plant-1). Estimated metabolizable energy concentration (MJ kg-1 DM) was significantly lower at the six-leaf stage (11.01 ± 0.06) than at any previous leaf regrowth stage, whereas CP concentration (g kg-1 DM) decreased with regrowth to the six-leaf stage. Both the levels of ME and CP concentrations were indicative of a high quality forage throughout regrowth (11.37 ± 0.04 and 279 ± 8.0 for ME and CP respectively). Results from this study give a basis for determining appropriate criteria for grazing cocksfoot-based pastures. The optimal defoliation interval for cocksfoot appears to be between the four- and five-leaf stages of regrowth. Delaying defoliation to the four-leaf stage allows time for replenishment of WSC reserves, resumption of root growth and an increase in tillering, and is before herbage is lost and quality falls due to onset of leaf senescence.
A live-trapping of Australian brush-tailed possums, Trichosurus vulpecula (Kerr), in the Orongorongo Valley, Wellington, New Zealand

A live-trapping study of a population of Australian brush-tailed possums, Trichosurus vulpecula (Kerr), in indigenous forest of the Orongorongo Valley, Wellington, N.Z. , was carried out from March 1966 to November 1968. In 14 ha of podocarp-mixed broadleaf forest, 301 possums (150; 151) were individually marked and repeatedly captured in a series of trapping periods. The population comprised residents and transients of both sexes with sub- adults forming the bulk of the latter, particularly in spring. The estimated population density varied from 10.6 per ha in November 1966 to 6.4 per ha in August 1968. There was one well-defined season of births each autumn and a few births in winter. On average, 73% (67-92%) of mature females produced pouch young each year. Females resident throughout the study had the highest breeding success (79%). Achievement of sexual maturity was delayed; no females bred until they were 2 yr old, and some not even at 3 yr. Losses occurred at all stages of the life history and averaged 62% between the pouch young and subadult stages; thus only 28 subadults per 100 females were recruited. Adult losses averaged 26% per annum. Adult males (mean weight 2.46 kg) were heavier than adult females (2.33 kg). Weights varied seasonally, with males heaviest in summer and lightest in spring, and females heaviest in winter and lightest in summer. Possums of both sexes were rather sedentary, with males (95% of captures within 115 m of the initial capture site) being less so than females (95 % of captures within 90 m of the initial capture site). More than half of the captures (55% for males, 62% for females) were made within 30 m of the site of initial capture. Males moved farther in autumn and summer than in other seasons, while females did so in autumn and winter. Subadults were apparently more sedentary than adults. Home ranges of adult males (mean 0.81 ha) were significantly larger than those of adult females (0.46 ha). Considerable overlapping of the ranges of both sexes occurred, and territorial behaviour was not conspicuous. The dispersion of the population remained the same throughout the study although the component individuals changed. The results of the present study are compared with those of similar studies in New Zealand and Australia, and the dynamics of the Orongorongo Valley possum population are discussed with reference to variable rates of reproduction and mortality.
Association of Pressure Induced Hypertension with Specific Area of Ventrolateral Surface of Medulla Oblongata and Catecholamine Neurons

The rostral ventrolateral medulla (RVLM) is considered to be a major center for the regulation of sympathetic and cardiovascular activities. Several clinical studies have indicated a possible causal relationship between vasculoneural contact of the RVLM and essential hypertension. We previously reported that pulsatile compression of the ventral surface of the unilateral RVLM with a pulsating probe in anesthetized (with urethane) and artificially ventilated rats elevates arterial pressure, heart rate, and sympathetic nerve activity [28]. However, we have not investigated how and what kind of neurons are activated by compression. Therefore, we performed compression experiments in rats and examined the expression of c-fos, a marker of neuronal activation. The data indicate that after the compression of the ventral surface of the RVLM, c-fos mRNA was increased in the rostral and caudal ventrolateral medulla and the number of neurons containing specifically induced Fos-protein was considerably larger. They also suggest that the Fos-positive neurons also contain tyrosine hydroxylase, indicating that mechanical pressure (compression)-stimulated neural excitation occurred in the A1/C1 catecholamine-neurons and the specific area in the ventral surface of the RVLM is sensitive to compression.
A model study on the relation between atmospheric boundary-layer dynamics and poleward atmospheric moisture transport in Antarctica

A regional atmospheric model was used to study the relationship between atmospheric boundary-layerdynamics and moisture transport toward the Antarctic grounded ice sheet. The model was integratedfor a 14-yr period (1980—1993) using a grid spacing of 55 km. Re-analyses from the European centrefor medium-range weather forecasts were used to force the model from the lateral boundaries. Seasurface temperature and sea ice extent were prescribed from daily observations. It was found that theboundary layer responds passively to the large-scale circulation rather than being the driving force forthe meridional circulation and moisture advection toward the ice sheet. Moisture transport by the meancirculation is directed from the ice sheet toward the Southern Ocean and transient eddies are responsiblefor the moisture transport toward the ice sheet. Frequent interruption of the katabatic winds by passinglow-pressure systems characterise years with a large poleward moisture transport. Therefore there isa negative correlation between the annual mean poleward moisture transport and both the directionalconstancy and the southerly wind component in the boundary layer near the ice edge. A case study forJuly 1980 shows that the wind and the specific humidity in the middle and higher troposphere determinethe poleward atmospheric moisture transport in Wilkes Land and that the moisture advection in theboundary layer is insignificant in this region.
FARELO DO MESOCARPO DE BABAÇU NA TERMINAÇÃO DE TOURINHOS: CARACTERÍSTICAS DA CARCAÇA E CORTES SECUNDÁRIOS DO TRASEIRO ESPECIAL

We evaluated carcass characteristics, weight and percentage of prepared commercial cuts of the primal pistol cut (PC) of 30 young crossbred bulls fed diets which included replacement levels (0, 25, 50, 70 and 100% of the dry matter, DM) of corn by babassu mesocarp bran (BMB). The experiment was a completely randomized design with six replicates. Slaughter weight was not affected by treatments. Hot and cold carcass weights decreased linearly (P<.05) at 230 g and 250 g, respectively, for each 1 kg of replacement, and hot carcass yield (HC) decreased by 3.2 g/kg of HC for each 1 kg of DM of BMB in the diet (P<0.05). Subcutaneous fat thickness presented a quadratic (P<.05) response with maximum point estimated by the regression equation of 4.29 mm with 33.3% substitution. The proportion of PC of the carcass increased linearly as levels of BMB in the diet increased (P<.05). The percentage of side cut showed a quadratic response (P<.05), with maximum point estimated with 33.3% substitution. The weight of the prepared commercial cuts of the PC, striploin, knuckle and eye round, and the percentage of tenderloin, topside and shank, were influenced by the diet (P<0.05). There was no change in prepared meat cuts yields of PC (73.22%) (P<.05). The use of babassu mesocarp bran to replace corn in cattle finishing diets does not affect the weight and meat yield of the pistol cut, but decreases linearly hot carcass weight, and subcutaneous fat thickness at replacement levels above 33.3%. KEYWORDS: biofuel; by-products; carcass yield; feedlot; meat yield; tenderloin.
Probabilistic hindcasts and projections of the coupled climate, carbon cycle and Atlantic meridional overturning circulation system: a Bayesian fusion of century-scale observations with a simple model

Abstract How has the Atlantic Meridional Overturning Circulation (AMOC) varied over the past centuries and what is the risk of an anthropogenic AMOC collapse? We report probabilistic projections of the future climate which improve on previous AMOC projection studies by (i) greatly expanding the considered observational constraints and (ii) carefully sampling the tail areas of the parameter probability distribution function (pdf). We use a Bayesian inversion to constrain a simple model of the coupled climate, carbon cycle and AMOC systems using observations to derive multicentury hindcasts and projections. Our hindcasts show considerable skill in representing the observational constraints. We show that robust AMOC risk estimates can require carefully sampling the parameter pdfs. We find a low probability of experiencing an AMOC collapse within the 21st century for a business-as-usual emissions scenario. The probability of experiencing an AMOC collapse within two centuries is 1/10. The probability of crossing a forcing threshold and triggering a future AMOC collapse (by 2300) is approximately 1/30 in the 21st century and over 1/3 in the 22nd. Given the simplicity of the model structure and uncertainty in the forcing assumptions, our analysis should be considered a proof of concept and the quantitative conclusions subject to severe caveats.