Annual Fall Research Articles

Evaluation of Classification Algorithms to Predict Largemouth Bass (Micropterus salmoides) Occurrence

This study aimed to evaluate classification algorithms to predict largemouth bass (Micropterus salmoides) occurrence in South Korea. Fish monitoring and environmental data (temperature, precipitation, flow rate, water quality, elevation, and slope) were collected from 581 locations throughout four major river basins for 5 years (2011–2015). Initially, 13 classification models built in the caret package were evaluated for predicting largemouth bass occurrence. Based on the accuracy (>0.8) and kappa (>0.5) criteria, the top three classification algorithms (i.e., random forest (rf), C5.0, and conditional inference random forest) were selected to develop ensemble models. However, combining the best individual models did not work better than the best individual model (rf) at predicting the frequency of largemouth bass occurrence. Additionally, annual mean temperature (12.1 °C) and fall mean temperature (13.6 °C) were the most important environmental variables to discriminate the presence and absence of largemouth bass. The evaluation process proposed in this study will be useful to select a prediction model for the prediction of freshwater fish occurrence but will require further study to ensure ecological reliability.

Exploring the Role of Cognition in the Annual Fall Migration of the Monarch Butterfly (Danaus plexippus).

Simple SummaryEach year, millions of monarch butterflies in eastern North America undergo a spectacular fall migration to overwintering sites in central Mexico, where they remain until returning northward in the spring. In addition to the navigational challenges faced during the southward flight, migratory individuals are also challenged with the foraging task of locating high-quality nectar sources for overwinter survival in the face of unfamiliar floral landscapes that change in complex and unpredictable ways. In the research reported here, a proboscis extension paradigm is used to investigate learning and long-term memory abilities that might help fall migrants meet these unique foraging demands. Male and female migratory and captive-reared individuals were consecutively trained to perform color and odor cue discriminations and then tested for their ability to simultaneously retain reward information associated with each cue in memory without reinforcement over a period of 7 days. Results showed that male and female fall migrants can learn the reward properties of color and odor cues with over 75% accuracy after less than 40 s of exposure and can simultaneously retain visual and olfactory information predicting the availability of floral rewards in memory without reinforcement for at least 7 days. Captive-reared male butterflies also showed the ability to retain visual and olfactory information in long-term memory for 7 days; however, 80% of captive-reared females could not retain color cues in long-term memory for more than 24 h. These novel findings are consistent with the view that monarch butterflies have enhancements to long-term memory that enable them to minimize the amount of time and energy wasted searching for suitable nectar sources during their annual fall migration, thereby optimizing migratory performance and increasing the chance of overwinter survival. The possibility that female monarchs undergo a seasonal change in visual long-term memory warrants further empirical investigation.Each fall, monarch butterflies in eastern North America undergo an extraordinary long-distance migration to wintering areas in central Mexico, where they remain until returning northward in the spring. Migrants survive the overwintering period by metabolizing lipid reserves accumulated exclusively though floral nectar; however, there is little known about how individuals maximize foraging efficiency in the face of floral environments that constantly change in complex and unpredictable ways along their migratory route. Here, a proboscis extension paradigm is used to investigate the role of cognition during the foraging phase of monarch migration. Male and female migratory butterflies were consecutively trained to discriminate between two color and odor cues and then tested for their ability to simultaneously retain the information on the reward value of each cue in memory without reinforcement over a period of 7 days. To gain further insight into cognitive abilities of monarchs as a migratory species, a second set of captive-reared males and females were tested under harnessed conditions at the same time as wild-caught fall migrants. Results showed that male and female migrants can learn the reward properties of color and odor cues with over 75% accuracy after less than 40 s of exposure and can simultaneously retain visual and olfactory information predicting the availability of floral rewards in memory without reinforcement for at least 7 days. Captive-reared male butterflies also showed the ability to retain visual and olfactory information in long-term memory for 7 days; however, 80% of captive-reared females could not retain color cues in long-term memory for more than 24 h. These novel findings are consistent with the view that monarch butterflies, as a migratory species, have enhancements to long-term memory that enable them to minimize the amount of time and energy wasted searching for suitable nectar sources during their annual fall migration, thereby optimizing migratory performance and increasing the chance of overwinter survival. The possibility that female monarchs undergo a seasonal change in visual long-term memory warrants further empirical investigation.

TransparC2U–A two-pool, pedology oriented forest soil carbon simulation model aimed at user investigations of multiple uncertainties

The dynamic character of forest soil organic carbon (SOC) stocks is demonstrated in the simulation model TransparC2U. The model has up to 10 layers, each with two pools with first order kinetics running for 40 years. The model is aimed at teaching soil science to a broad audience in academia, extension services, secondary schools and public life. The learning objective of the model is to bring about an understanding of SOC dynamics over time, uncertainty, and the complexity of the soil profile with its pedogenesis represented by soil horizons. The user works in an illustrated spreadsheet calculator with options for instant and interactive exploration of the multiple uncertainties and constraints on forest SOC stocks. The user divides the initial SOC stock in each horizon into two pools, Cnew with faster mineralization, and Cold with very slow mineralization, based on their knowledge of horizon designations and stabilization mechanisms.Data from 23 soil Nordic and Baltic forest soil profiles with horizons characterized by chemical and physical properties are available. Site information to the user intended for reflections on choosing parameter values includes soil classification, tree species, climate, stand age, soil nutrient status and properties that govern physical or chemical protection of soil C (extractable phosphorus (P), total nitrogen (N), subsoil clay content and extractable iron (Fe)). Other changeable inputs are the average annual aboveground litter fall, root litter allocation to individual soil horizons as a fraction (%) of aboveground input, and decomposition rates of each pool. The game played aims for preservation of the initial C stock by manual calibration by the user. The sensitivity of the potential C change (dC ±) is tested by changing the parameter values and watching the effects on model results, i.e. C stocks in each horizon over time. The sensitivity analysis can involve the uncertainty of the input, the initial C content in each horizon, the fraction of Cold and the turnover rates that represent heterotrophic respiration.The processes representing C input to deeper horizons (roots and exudates), bioturbation by macrofauna, as well as podzolisation provide optional transfer of C between the forest floor and mineral soil layers when judged appropriate by the user based on the site and stand information.The user may interpret results of the simulation by examining the outputs of total C stock change over 40 years by inspecting total N and P requirements for new litter inputs against potentially available current and future N and P stocks in the soil and the capacity of C binding by subsoil clay and Fe-oxides. It highlights the physical and chemical soil properties required to justify the simulated fate of new and old SOC and the sensitivity of controlling parameters on a decadal timescale to the user.

Phytotoxic Substances Involved in Teak Allelopathy and Agroforestry

Teak (Tectona grandis L.f.) is one of the most valuable timber species, and is cultivated in agroforestry systems in many countries across the tropical and subtropical regions of the world. The species is also one of the most essential trees in home gardens in South Asia due to its wood quality and medicinal value in folk remedies. It is a deciduous tree species, and the amount of litter that falls from teak trees is huge. The decomposition rate of the litter is relatively fast in tropical humid conditions. The interactions between teak and weeds, or crops, under the teak trees have been evaluated in terms of allelopathy. Evidence of allelopathy is documented in the literature over the decades. The leachate and extracts of teak leaves suppress the germination and growth of several other plant species. Phytotoxic substances, such as phenolics, benzofurans, quinones, terpens, apocarotenoids and phenylpropanoids, in the teak leaves, were isolated and identified. Some phytotoxic substances may be released into the soil under teak trees from leaf leachate and the decomposition of the litters, which accumulate by annual leaf fall and can affect the germination and growth of undergrowth plant species as allelopathic substances. The allelopathy of teak is potentially useful for weed management options in agroforestry and other agriculture systems to reduce commercial herbicide dependency. It was also reported that agroforestry systems with teak enhance income through the production of crops and woods, and provide energy efficiency for crop cultivation.

The stabilizing effects of economic policies in Spain in times of COVID-19

Purpose This paper aims to analyse the stabilizing macroeconomic effects of economic policies during the COVID-19 crisis in Spain. Design/methodology/approach The contribution of the structural shocks that explain the behaviour of the main macroeconomic aggregates during 2020 are estimated, and the effects of economic policies are simulated using a dynamic stochastic general equilibrium (DSGE) model estimated for the Spanish economy. Findings The results highlight the importance of supply and demand shocks in explaining the COVID-19 crisis. The annual fall in gross domestic product (GDP) moderates at least by 7.6 points in the most intense period of the crisis, thanks to these stabilizing policies. Finally, the potential effects of Next Generation EU in the Spanish economy are estimated. Assuming that Spain may receive from the EU between 1.5 and 2.25 percentage points (pp) of GDP, activity could increase to between 2 and 3 pp in 2024. Originality/value To the best of the authors’ knowledge, the exercises and findings are original. All these results show the usefulness of a DSGE model, such as the estimated rational expectation model for Spain, as a practical tool for the applied economic analysis, the macroeconomic assessment of economic policies and the understanding of the Spanish economy.

A Bayesian network approach for geotechnical risk assessment in underground mines

SYNOPSIS Underground mining gives rise to geotechnical hazards. A formal geotechnical risk assessment can help to forecast and mitigate these hazards. Frequentist probability methods can be used when the hazard does not have many variables and a lot of data is available. However, often there is not enough data for probability distributions, such as in the case of new projects. The risk assessment is often subjective and qualitative, based on expert judgement. The purpose of this research is to present the use of Bayesian networks (BNs) as an alternative to existing risk assessment methods in underground mines by combining expert knowledge with data as it becomes available. Roof fall frequency forecasting using parameter learning is demonstrated with 1141 sets of roof fall data across 12 coal mines in the USA. The prediction is nearly identical for individual mines, but when multiple mines are evaluated it is difficult to find a single best fit distribution for annual roof fall frequency. The BN approach with TNormal distribution was twice as likely to fit the observed data compared to the Poisson distribution assumed in the past. A hybrid approach using BN combining multiple probability distribution curves from historical data to predict annual roof fall is proposed. The BN models can account for variability for multiple parameters without increasing the complexity of the calculation. BNs can work with varying amounts of data, which makes them a good tool for real-time risk assessment in mines. Keywords: Bayesian network; expert opinion models; geotechnical risk; incident forecasting; parameter learning; roof fall risk.

Comparison of performance of F1 Romanov crossbred ewes with wool and hair breeds during fall lambing and body weight and longevity through six production years.

The objective of this study was to evaluate wool (Dorset and Rambouillet) and hair (Dorper, Katahdin, and White Dorper) breeds for their ability to complement Romanov germplasm in an annual fall lambing system by estimating direct maternal grandsire and sire breed effects on economically important lamb and ewe traits. After 3 yr of evaluation under spring lambing, ewes of the five F1 types were transitioned to spring mating, exposed to composite terminal sires, and evaluated under a barn lambing system at 4, 5, and 6 yr of age. A total of 527 first generation crossbred (F1) ewes produced 1,151 litters and 2,248 lambs from 1,378 May exposures. After accounting for differences in dam age, birth type, and sex, lamb survival to weaning was unaffected by maternal grandsire breed (P = 0.30). However, lambs born to 50% Dorset (16.8 ± 0.21 kg) or 50% White Dorper ewes (16.8 ± 0.28 kg) were heavier at weaning than those born to 50% Katahdin dams (13.8 ± 0.32 kg; P < 0.001). Additionally, lambs born to 50% Dorset ewes were heavier than those born to 50% Rambouillet (16.0 ± 0.22 kg) and 50% Dorper ewes (15.7 ± 0.33; P ≤ 0.03), but no other pairwise maternal grandsire breed differences were observed (P ≥ 0.06). Ewe body weight (n = 3,629) was recorded prior to each of six possible mating seasons and, across ages, was greatest for Dorset- and Rambouillet-sired ewes (56.7 ± 0.44 and 56.5 ± 0.45 kg, respectively), intermediate for Dorper- and White Dorper-sired ewes (54.7 ± 0.78 and 54.1 ± 0.64 kg, respectively), and least for Katahdin-sired ewes (51.5 ± 0.45 kg). Fertility after spring mating (0.80 ± 0.03 to 0.87 ± 0.02), litter size at birth (1.46 ± 0.09 to 1.71 ± 0.07), and litter size at weaning (1.25 ± 0.06 to 1.46 ± 0.06) were not impacted by sire breed (P ≥ 0.16). Ewe longevity, assessed as the probability of being present after 6 production years, was also not affected by sire breed (0.39 ± 0.03 to 0.47 ± 0.03; P = 0.44). Rambouillet-sired ewes weaned more total weight of lamb (21.5 ± 0.94 kg) than Katahdin-sired ewes (17.8 ± 0.94 kg; P = 0.05), but no other sire breed differences were detected (P ≥ 0.07). Results demonstrated that incorporating the Romanov into a crossbreeding system is a practical means of improving out-of-season ewe productivity.

A Postural Assessment Utilizing Machine Learning Prospectively Identifies Older Adults at a High Risk of Falling.

Introduction: Falls are the leading cause of accidental death in older adults. Each year, 28.7% of US adults over 65 years experience a fall resulting in over 300,000 hip fractures and $50 billion in medical costs. Annual fall risk assessments have become part of the standard care plan for older adults. However, the effectiveness of these assessments in identifying at-risk individuals remains limited. This study characterizes the performance of a commercially available, automated method, for assessing fall risk using machine learning.Methods: Participants (N = 209) were recruited from eight senior living facilities and from adults living in the community (five local community centers in Houston, TX) to participate in a 12-month retrospective and a 12-month prospective cohort study. Upon enrollment, each participant stood for 60 s, with eyes open, on a commercial balance measurement platform which uses force-plate technology to capture center-of-pressure (60 Hz frequency). Linear and non-linear components of the center-of-pressure were analyzed using a machine-learning algorithm resulting in a postural stability (PS) score (range 1–10). A higher PS score indicated greater stability. Participants were contacted monthly for a year to track fall events and determine fall circumstances. Reliability among repeated trials, past and future fall prediction, as well as survival analyses, were assessed.Results: Measurement reliability was found to be high (ICC(2,1) [95% CI]=0.78 [0.76–0.81]). Individuals in the high-risk range (1-3) were three times more likely to fall within a year than those in low-risk (7–10). They were also an order of magnitude more likely (12/104 vs. 1/105) to suffer a spontaneous fall i.e., a fall where no cause was self-reported. Survival analyses suggests a fall event within 9 months (median) for high risk individuals.Conclusions: We demonstrate that an easy-to-use, automated method for assessing fall risk can reliably predict falls a year in advance. Objective identification of at-risk patients will aid clinicians in providing individualized fall prevention care.

DETEKSI DINI RESIKO JATUH PADA LANSIA DI POSYANDU LANSIA KENTINGAN, KECAMATAN JEBRES, SURAKARTA

Background :The falling risk is an event reported by a patient or family who sees an incident, which results in a person suddenly lying, sitting on the floor or lower place with or without loss of consciousness or injury. Falls can occurwhen the body’s postural, control system fails to detectshifting and not repositioning the center of gravity toward the body support at the right time. In Indonesia, the elderly who live in communities experience an annual fall or around 30%. The incidence of falls in the elderly living in the community increased from 25% at the age 70 to 35% after being over 75 years old. One cause of the fall is a disturbance in the pattern of roads. Therefore it is necessary to practice early detection of the risk of falling in the elderly. Target and output 100% of extension participants consisting of the elderly can increase their knowledge and understanding of early detection training on the risk of falling on the elderly. Methods of conducting lectures and demonstrations or exercises. The result of the elderly can mention how to detect risk in the elderly and can do exercises to prevent falls. Conclusion elderly know how to detect the risk of early fall in the elderly.

Shaping the Future of Science

As Earth and space scientists gather this December for AGU’s annual Fall Meeting, Eos looks at the ways in which the community is reimagining itself to create a more diverse and adaptable future.

Metapopulation dynamics over 25\xa0years of a beetle, Osmoderma eremita, inhabiting hollow oaks

Osmoderma eremita is a species of beetle that inhabits hollows in ancient trees, which is a habitat that has decreased significantly during the last century. In southeastern Sweden, we studied the metapopulation dynamics of this beetle over a 25 year period, using capture-mark-recapture. The metapopulation size had been rather stable over time, but in most of the individual trees there had been a positive or negative trend in population development. The probability of colonisation was higher in well-connected trees with characteristics reflecting earlier successional stages, and the probability of extinction higher in trees with larger diameter (i.e. in later successional stages), which is expected from a habitat-tracking metapopulation. The annual tree mortality and fall rates (1.1% and 0.4%, respectively) are lower than the colonisation and extinction rates (5–7%), indicating that some of the metapopulation dynamics are due to the habitat dynamics, but many colonisations and extinctions take place for other reasons, such as stochastic events in small populations. The studied metapopulation occurs in an area with a high density of hollow oaks and where the oak pastures are still managed by grazing. In stands with fewer than ten suitable trees, the long-term extinction risk may be considerable, since only a small proportion of all hollow trees harbours large populations, and the population size in trees may change considerably during a decade.

Morphological Characterization and Evaluation of Mungbean (Vigna radiata (L) Wilczek) Genotypes in Western Tigray, Ethiopia

The experiment was conducted to characterize and evaluate mung bean accessions, to identify diseases, shattering, lodging resistant and suitable for combine harvesting. The accessions sown in a plot area of 2.1 m by 5 m with 1 m, 1.5m between plots and blocks keeping inter and intra row spacing of 40 cm and 10 cm, respectively. 73 entries along with two checks summing up 75 genotypes evaluated at field condition for their yield and yield components characters during 2019 main cropping season using augmented RCBD design without replication. R-software were used to analyze different characters including the descriptive statistics and SPSS20 used to analyze clustering. Mean of different traits days to maturity (76.46±11.21,), shattering(0.93±0.14), lodging (2.71±2.03), root length(21.±5.54), root volume(201.05±43.76), pods/plant (16.81±6.38), nodule number( 16.22±1.96), Seed yield(10.64±4.01), seeds/pod (11.77±2.80) and 100sw(3.26±0.97) was recoded. The accessions recorded different range of parameters; nodule number (0 to71.75), root length (8 cm to 34.5), shattering (0 to 100), lodging (0% to 1-10%), number of seeds/pod (7 to 23), hundred seed weight (1.8 to 3.26 gram), root volume (4.71 to 230.46 CM) respectively this big variation among accessions of different traits helps to promote breeding programme in mung bean. The seed yield of genotypes ranged from ZURD01(3.88) to ILRI6831(19.79) qtha-1. Days to maturity was ranged from 61(ARKEBE) to 103(MEND01) after emergence. Three maturity groups; early (61 to 69days), medium (71 to 79 days) and late maturing (81 to 103days). Mean yield performance; cluster one had the highest mean yield (16.31qtha-1) followed by cluster two (12.43 qtha-1), cluster three (9.8), cluster four (6.65 qtha-1) and cluster five (1.21 qtha-1) respectively. The genotypes grouped in to three clusters based on their maturity and cluster one had the highest mean maturity days (91.74) followed by cluster two (75.97) and cluster three (66.37) respectively. The early, medium and late maturing genotypes recommended for moisture stress (350-500mm), optimum (600-800 mm) and high rain fall (900-2000 mm) areas respectively according to annual rain fall of the agro ecologies. Genotypes with high nodule number, high yielding, diseases resistance, better root length, shattering and lodging resistance will be important for variety development for mechanization, commercial production and further breeding programme.

The ICDP Dead Sea deep drilling project – introduction

This research provides insights into the formation of the coastal cliffs comprising the staircase morphology along the western coast of the Dead Sea as a result of its anthropogenic, regressive modern (last ~50 years) lake-level fall. The analysis of this morphology is based on observations and measurements of the impact of seasonal lake-level rises of 0–0.2 m and 0.7–2 m in normal versus exceptionally wet winters, respectively. We conducted repeated detailed topographic surveys of the shores for characterizing the evolving morphology with time, and coupled them with wind speed and wave amplitude during cliff formations. The detailed lake-level curve and the almost monotonic level decline allow associating each cliff with the exact year and season of its formation. This detailed chronology allowed, in turn, to identify and associate the pronounced and well-documented seasonality in the lake-level fall with the wind and wave data during specific seasons, years, and multi-year episodes. As a result, we can point at the controlling processes and environmental conditions for cliff formation. Under the regional Mediterranean climate with its distinct seasonality, winters are characterized by eastern Mediterranean low-pressure systems, generating the Jordan River flow in its northern headwaters and its discharge into the lake; this discharge controls the level fluctuations. At the Dead Sea area, these winter systems precipitate little. However, they generate high winds and storm waves that erode an additional coastal cliff at the base of the preexisting staircase every winter. Therefore, at the seasonal scale, a clear separation exists between (a) individual, cliff-forming, stronger wind storms operating only during winters under relatively stable water levels, and (b) the ~1-m annual lake-level fall, mostly during summers. This pronounced seasonality in both the wind and lake level (a) dictates the seasonal pace of cliff formation at vertical intervals similar to the magnitude (~1 m) of the annual lake-level fall by evaporation and artificial brine diversion, and (b) facilitates the cliff separation in the landscape. This regular pacing by winter storms, the minor lake-level rises, and the annual evaporation and diversion support the preservation of the individual cliffs that assemble into the staircase morphology in the coarse-clastic delta fronts and mudflats characterizing the recently emerging coast. Anomalous lake-level rises during exceptionally wet winters are more erosive, even with regular wind storms; they create the largest lateral erosion. Under the emerging shore topography, which results from the steep bathymetry, the outcome is cliffs often much higher than the respective amplitude of their causative lake-level rises. This depends on the duration of the rise and of individual storms and indicates that under the variance of the modern hydroclimatology, the abnormal seasonal lake-level rises operating with regular winter storms, can aggressively erode the shore.Proposed plans to stabilize or raise the falling water level of the Dead Sea would induce coastal erosion and stream incision, which would threaten the existing highway and other infrastructure built close to its shore.

After COVID-19, a future for the world's children?

After COVID-19, a future for the world's children?

Halophyte ion regulation traits support saline adaptation of Lepidium latifolium, L. draba, and L. alyssoides

Identification of saline resistance traits of invasive plants has received little study and could reveal how some plant species utilize salt to encroach upon salinized landscapes. We conducted a 3-mo greenhouse study to identify saline resistance mechanisms of three North American invasive Brassicaceae species, Lepidium latifolium, L. draba, and L. alyssoides, in response to increasing salinity. Seedlings of central and southern New Mexico, USA populations were exposed to NaCl irrigation solutions at 0, − 0.1, and − 0.2 MPa (0, 24, and 48 mM, respectively). Saline resistance of these populations was attributable to salt tolerance behavior commonly observed as signature traits of halophytes, including a combined Na and Cl accumulation in leaves of up to 13% of dry weight with no injury, dominance of leaves as the salt accumulation site, leaf tissue water Na and Cl at ≈ 300–400 mM, leaf K:Na molar ratio of less than 1, and the development of leaf succulence. In saline environments, high salt loads in shoots may increase soil salinity through annual litter fall and potentially alter vegetation community structure. A broader implication of this study is in the need to detect salt resistant traits of additional plant species to broaden the narrow understanding of how salinity affects vegetation communities.

Now that we have a State Microbe, where do we go from here?

This lecture on the state microbe was initially delivered at the annual fall meeting of the Medical History Society of New Jersey on Thursday, October 10, 2019 at the Nassau Club of Princeton.

Trustees Approve Changes to DSM, New Position Statements

Trustees Approve Changes to <i>DSM</i>, New Position Statements

Examining the glacial lake dynamics in a warming climate and GLOF modelling in parts of Chandra basin, Himachal Pradesh, India

The presented study reports applicability of Lake Detection Algorithm (LDA) for an automated extraction of glacial lakes over a large geographical region and dynamics of Samudra Tapu and Gepang Gath glacial lakes. The areal extent of lake boundary extracted through LDA and areal extent of manually interpreted lake boundary exhibit a remarkable agreement (R2~0.99). Glacial lake dynamics is assessed in terms of areal and volumetric expansion for two selected glacial lakes from 1979 to 2017, i.e. Samudra Tapu (0.95 km2), and Gepang Gath (0.67 km2). They show volumetric expansion from 8.52 × 106 m3 (1979) to 80.34 × 106 m3 (2017) and 2.04 × 106 m3 (1979) to 32.44 × 106 m3 (2017) respectively. Statistical analysis (Mann-Kendall and Sen's slope) of climate data indicates rise in mean annual temperature (0.021 °C yr−1; 1961–2015) and fall in annual precipitation (−2.74 mm yr−1; 1951–2015) at different confidence intervals. Further Glacial Lake Outburst Flood (GLOF) is modelled using empirical relationship and Simplified Dam Breach Model (SMPDBK). The SMPDBK demonstrates discharge of 3866.52 and 2100.90 m3 s−1 reaching Chhatru and Sissu village posing threat to life and property. The study also exhibits that glacial shrinkage under the influence of climate change causes expansion of glacial lakes. This expansion is expected to intensify catastrophic GLOF and resultant fatalities and destruction in the downstream region.

Comparison of water-physical and microbiological properties of apple orchards soils with indicators in other agricultural lands

The aim of the research is to compare the physical properties and biological activity of the soil in apple orchards with the soils of other lands: strawberry, chokeberry, black currant plantations, field crop rotation, forest plantations, and deposits. In apple orchards, in a layer of 0-40 cm row-spacing, there is a relatively low content of agronomically valuable, water-resistant aggregates, and the lowest moisture capacity. Due to the significant accumulation of snow in the garden and the annual leaf fall of the apple tree in the trunk strips, the same high cellulolytic activity is maintained as in other woody phytocenoses.

서울대학교 음악대학 국악과 60년, 국악 정기연주회의 성과

서울대학교 음악대학 국악과는 1959년 신설되었으며, 1961년부터 매년 가을 국악 정기연주회를 개최하였다. 연주단체이자 교육기관으로서 국악계에서의 서울대학교 음악대학 국악과의 역할은 시대의 흐름에 따라 변화하였음을 국악 정기연주회를 통해 확인하였다. 1960~70년대는 정악 중심의 전통음악 전수 및 신작 국악 진흥에 기여하였다. 서울대학교 음악대학 국악과는 광복 이후 등장한 최초의 대학 국악교육기관이면서 동시에 중요한 국악 연주단체 중 하나였다. 때문에 서울대학교 음악대학 국악 정기연주회는 단순히 학생들의 연주회 그 이상의 의미를 갖고 있었으며, 그 중심에는 이 시기의 대표적인 지휘자와 작곡가로 활동한 한만영 교수와 이성천 교수의 기여가 있었다. 1980년대부터는 공연 프로그램과 편성이 정형화되었다. 이 시기 국악 정기연주회의 프로그램은 제1부 전통, 제2부 창작음악의 구성으로 정형화된 후 전통은 민속악, 창작은 국악관현악을 중심으로 레퍼토리 및 편성의 확장이 이루어졌다. 이러한 양상은 전문 국악 연주단체가 많아지고 활성화된 외부적 요인과 함께 입학정원의 증원 및 성악실기전공 개설 등의 내부적 요인이 작용하였기 때문이다. 2000년을 전후로 민속악 및 창작실내악을 중심으로 한 레퍼토리의 확장이 이루어지기 시작하였다. 이 시기 국악 정기연주회는 시대적 흐름을 받아들여 민속악합주, 소규모 편성의 실내악 등 다양한 규모와 편성의 창작음악을 레퍼토리로 확장하였다. 최근에는 다양한 편성의 창작음악을 다루는 공연으로의 전문화가 이루어졌다. 2015년부터 참가한 대학국악축제를 계기로 현대음악의 관점에서 창작국악을 학습할 수 있는 기회를 마련하였으며, 2017년부터는 창작음악만으로 공연 프로그램을 구성하는 한편 재학생의 작품을 프로그램에 편성하여 학생들의 창작의욕을 고취시키고자 하였다. 더불어 국악관현악 편성에 있어 찰현악기의 편성비율을 높이고 개량가야금과 아쟁을 기본악기로 편성하는 등 전문연주단체의 관현악편성의 변화양상이 동일하게 나타났다. 즉, 서울대학교 음악대학 국악 정기연주회는 1960~70년대에는 신작 국악을 선도적으로 소개하는 무대로, 1980년대 이후로는 공연계의 흐름을 파악하고 이를 연마하는 교육의 장으로서 레퍼토리와 악기편성을 확장하고 변화시켜 왔음을 확인하였다. 학과의 신설 초기에는 재학생들의 교육과 더불어 ‘작곡가들이 창작품을 발표할 수 있는 무대’로서 ‘국악의 현대화’에 선도적 역할을 하였다. 그러나 1980년대 이후 국립국악원, 서울시립국악관현악단 등의 전문연주단체들의 등장과 활동에 따라 연주자 양성교육의 일환으로 기성 국악연주단체들의 공연레퍼토리나 관현악편성 등을 참고하여 국악 정기연주회의 내용을 변화ㆍ발전시켜 왔다. 이상 60여 년간의 국악 정기연주회의 성과를 참고하여 앞으로도 대학교육기관의 정기연주회로서의 역할을 키워나가기를 기대한다.