Mm In August Research Articles

The energy-limited water loss of an alpine shrubland on the northeastern Qinghai-Tibetan Plateau, China

Study regionAlpine shrubland on the northeastern Qinghai-Tibetan Plateau. Study focusWater provision ability is a pivotal ecological service of high-altitude alpine regions and is controlled by precipitation, evapotranspiration (ET), and soil water storage whereas the underlying ecohydrological processes remain highly unquantified. Here, we investigated continuous 19-year flux measurements to quantify the temporal patterns of ET and water budget (precipitation minus ET, P−ET), as well as 0-20 cm soil water storage change (ΔSWS). New hydrological insights for the regionAt a monthly scale, ET peaked in July (96.7 ± 26.4 mm, Mean ± S.D.) and averaged 41.7 ± 31.9 mm, whose variations were determined by the slope of the saturation vapor pressure curve at air temperature, air and soil temperatures, regardless of vegetation growth stage. P−ET averaged 18.3 ± 26.3 mm in August and September while stayed deficit during the other months. The variations in P−ET were controlled by precipitation in the May-October growing season whereas by ET in the non-growing season from November to April. ΔSWS peaked in May (28.8 ± 11.2 mm) and September (3.0 ± 2.7 mm) and almost accumulated to zero over the whole season. At annual scales, none of ET, P−ET, and ΔSWS changed significantly. ET averaged 512.2 ± 68.4 mm and exceeded precipitation (459.1 ± 58.4 mm), likely due to the lateral flow supply of uphill locations. The variations in ET were regulated directly by bulk canopy resistance and indirectly by net radiation. P−ET averaged −53.2 ± 95.4 mm and demonstrated a clear water deficit (−51.6 ± 21.0 mm) during the non-growing season. The variations of P−ET were driven jointly by precipitation and ET, with opposite but equivalent effects. The dominance of thermal conditions and energy availability on ET variability manifested an energy-limited feature of water loss in the alpine shrubland. The temporal patterns in P−ET elucidated that the alpine shrubland plays the water retention rather than water provision function through transforming variable precipitation input into stable ET loss.

IMPACT OF GLOBAL WARMING ON AQUACULTURE IN NORWAY

While aquaculture is predicted to play a significant role in addressing future global food demands, climate change is having a complex impact on aquaculture output. Climate change will have an effect on output levels, growth, feeding efficiency, and consequently farm productivity and profitability. The most significant challenges facing aquaculture are current and future climate change, which affects the viability of fish farming in Norway and around the world. Global warming and climate change have resulted in a decline in lake waters, an increase in sea level, changes in streams, and changes in precipitation models, all of which have begun to have a negative influence on all aquatic animals. According to the findings of this study, the yearly maximum temperature was 21.1 °C in July and the lowest was -2.8 °C in January, with the minimum temperature ranging from 13.5 °C in July to -7.5 °C in January. The highest average temperature was 17.4 °C in July, and the lowest was -5.1 °C in January. In terms of precipitation, the greatest was 118 mm in August, while the lowest was 56 mm in March. In terms of rainy days, the highest total was 11 mm in August, while the lowest total was 6 mm in March. In November, the humidity reached 90%, whereas in June, it was 66%. On bright days, the highest daylight hours were recorded in June at 12.1 hours, and the lowest hours were recorded in December at 2.5 hours. In this research, we explicitly investigated how these climate components may affect aquaculture in Norway. As a result, because it affects the stability of fish farming, this significant environmental issue must be addressed. It is critical to shed light on and thoroughly analyse the elements related to climate change in order to avoid the damages that result from them, as well as to identify strategies to adapt to these conditions and limit their effects on production and productivity. Corrective efforts should be implemented to reduce climate change and its consequences on fish output.

Factors affecting mass movement hazards in and around Djoundé (FarNorth Region, Cameroon)

Djoundé and its surroundings in Maroua, Cameroon, have been subjected to natural hazards in recent decades. This work aims at studying and mapping the factors of mass movement hazards in the study area to produce a hazard map. To achieve this, various field and indoor works have been carried out. The field studies facilitated the collection of data and information regarding the history of mass movements and the identification of mass movement hazard types. It also supported the analysis of factors controlling the hazards. The indoor work led to mapping factors and producing a mass movement hazard map for the study area. The inventory reveals that the most frequent mass movements are falls of rock blocks and debris, as well as debris flows. These phenomena are induced by natural and anthropogenic factors, predisposing and triggering. These factors are empirically ranked according to their importance in causing the hazards. Predisposing factors include inselbergs with basaltic and trachytic boulders, cracks and fissures on rocks, steep slopes (>65 % in places), vegetation cover dominated by grassland and sporadic trees, rainfall (747.69 mm/year), temperature (33.9 °C in April) and livestock farming. Triggering factors include the opening of quarries and summer rainfall (237.71 mm in August). From the generated hazards map, it can be deduced that approximately 35 %, 40 % and 25 % of the study area have high, medium and low probabilities of mass movement initiation, respectively. The low probability areas are often subject to gully erosion, not mass movements. This study contributes to understanding factors controlling the mass movement hazards in northern Cameroon. In addition, results from this study are helpful for the local authorities in implementing sustainable management policies.

Reproductive development of female wallago catfish (Wallago attu) in captivity

The wallago catfish (Wallago attu) is a new potential fish for aquaculture in Vietnam. Data related to the reproductive cycle of W. attu in captivity are, however, not available. To provide reliable indicators for oocyte maturation (OM) and the spawning season of the captive W. attu, this study investigated the temporal variation in hepatosomatic and gonadosomatic indices, oocyte diameter and color (greenish vs yellowish), germinal vesicle migration, and plasma concentrations of estradiol-17β (E2) and vitellogenin (Vtg) in female broodstock in association with changes in light density, temperature and amount of rainfall during the reproductive cycle. The results of this study displayed a clear seasonality in all the investigated parameters. The highest concentration of E2 (2.6 ± 3.5 ng/mL) was found in April, followed by a peak of Vtg (543 ± 43 ng/mL) in June. Meanwhile, the largest mean oocyte diameter (1.70 ± 0.02 mm) was observed in June. The shortest distance between the germinal vesicle and the edge of the oocyte (0.20 ± 0.01 mm) was recorded in July. Correspondingly, the amount of rainfall increased remarkably in July from 43.9 mm to over 200 mm in August. Taken together, we conclude that OM and the onset of the spawning season of captive W. attu occur in July and August, respectively. The percentage of greenish oocytes increased significantly over sampling time points. The changes in the color of oocytes combined with oocyte diameter could, therefore, be considered as promising indicators to predict the OM and spawning season of captive W. attu.

Precipitation patterns in the Gambia from 1981 to 2020

The present study used composite analysis and rainy season definition to investigate rainfall patterns in The Gambia from 1981 to 2020. Rainfall dataset as observed by 10 meteorological stations scattered across The Gambia was used. Results showed that the highest single month rainfall ever recorded in The Gambia during the study period was observed in Sapu, in the eastern sector of the country. The station recorded a total rainfall amount of 767 mm in August, 1999, while the lowest single month rainfall ever recorded was 463 mm in September 2012. It was observed in Jenoi, a station situated in the western sector of the country. Climatological results showed that the study area experienced monomodal rainfall regime during the West African Monsoon, and that the southern part of the western sector region such as Sibanor tend to receive more rainfall compared to other regions of the study area. Part of the central region receives the least annual rainfall. The eastern sector of The Gambia received much of its rain from May to October with July - September as the peak of the rain season. During May - October, Sapu received the heaviest rainfall while Fatoto received the least amount. Results also show that July - September is the period when significant amounts of rainfall are received over the eastern sector of the study area. While May and October are both transitional months, the eastern sector of the study area receives more rains in October than in May. The western sector of the study area, on the other hand, received much of its rain from June to October with July - September as the peak of the rain season. During June - October, Sibanor received the heaviest rainfall while Jenoi received the least amount. The results also show that July - September is the period when significant amounts of rainfall are received over the western sector of the study area. Although June and October are both transitional months, the western sector receives more or less the same rain amounts in June and October. Results further found that, to avert losses associated with excess or deficit in crop water requirement, in the eastern sector, crops with high water requirement should be grown before August as maximum rainfall is observed in August, whereas crops with minimum water requirement should be grown in May or October, that is when minimum rainfall is experienced. In the western sector, on the other hand, crops requiring high water amount should be grown before August or September when maximum rainfall is recorded in the sector, whereas crops with minimum water requirement should be grown in June or October. This study will help create awareness on the erratic rain seasons due to Climate Change, and to provide farmers with information on rainfall distribution in The Gambia to avert losses and impacts associated with water deficit or excess on society, agriculture, and the environment.

Evaluating the Spatio-Temporal Distribution of Irrigation Water Components for Water Resources Management Using Geo-Informatics Approach

Spatio-temporal distribution of irrigation water components was evaluated at the canal command area in Indus Basin Irrigation System (IBIS) by using a remote sensing-based geo-informatics approach. Satellite-derived MODIS product-based Surface Energy Balance Algorithm for Land (SEBAL) was used for the estimation of the actual evapotranspiration (ETa). The ground data-based advection aridity method (AA) was used to calibrate and validate the model. Statistical analysis of the SEBAL based ETa and AA shows the mean values of 87.1 mm and 47.9 mm during Kharif season (May–November) and 100 mm and 77 mm during the Rabi Season (December–April). Mean NSEs of 0.72 and 0.85 and RMSEs 34.9 and 5.76 during the Kharif and the Rabi seasons were observed for ETa and AA, respectively. Rainfall data were calibrated with the point observatory data of the metrological stations. The average annual ETa was found 899 mm for defined four cropping years (2011–2012 to 2014–2015) with the minimum average value of 63.3 mm in January and the maximum average value of 110.6 mm in August. Average of the sum of net canal water use (NCWU) and rainfall during the study period of four years was 548 mm (36% of ETa). Seasonal analysis revealed 39% and 61% of groundwater extraction proportion during Rabi and Kharif seasons, dependent upon the occurrence of rainfall and crop phenology. Overall, the results provide insight into the interrelationships between key water resources management components and the variation of these through time, offering information to improve the strategic planning and management of available water resources in this region.

КЛИМАТИЧЕСКИЕ И ГИДРОЛОГИЧЕСКИЕ ФАКТОРЫ, ДЕЙСТВУЮЩИЕ В РАЙОНЕ СТВОРА ДЛЯ СТРОИТЕЛЬСТВА МОСТА «САХАЛИН–МАТЕРИК»

В настоящее время ни у одного нашего современника не вызывает сомнения целесообразность перевозок по Транссибирской магистрали, а ее значение для развития Сибири и Дальнего Востока вполне очевидно. Однако такое отношение к этой транспортной артерии сформировалось не сразу. Вспомним хотя бы тот факт, что томское купечество настояло на том, чтобы дорога проходила через Александровск (ныне Новосибирск). Решение Александра III о строительстве железной дороги сыграло судьбоносную роль. Проложенная дорога способствовала развитию городов, через которые она была проложена. Ситуация с решением вопроса об организации свободного перемещения с материка на Сахалин представляется нам схожей с той, которая была перед прокладкой линии через всю Сибирь. Вопрос придется рассматривать рано или поздно. Прокладка магистрали на остров даст мощный толчок социальному и экономическому развитию территорий, прилегающих к автомобильной и железной дороге, которые пройдут через мостовой переход. В этой статье изучается специфика климатических и гидрологических факторов, определяющих выбор створа гидротехнического сооружения в проливе Невельского. Актуальность исследования продиктована потребностью во всестороннем рассмотрении условий, определяющих выбор линии пересечения Татарского пролива мостовым переходом. После рассмотрения влияния геологических и геоморфологических факторов следует уделить внимание климатическим, погодным и гидрологическим процессам, которые будут оказывать постоянное воздействие на сооружение в период строительства и эксплуатации. Цель: свести воедино и проанализировать данные, характеризующие особенности атмосферных и гидросферных процессов в узкой части Татарского пролива, и провести научные исследования, которые послужат дополнением к инженерным изысканиям и помогут на основе моделирования выявить наиболее безопасный створ для возведения гидротехнического сооружения, которое соединит берега. Материалы и методы. Материалами для исследования послужили картографические материалы, данные дистанционного зондирования Земли, сведения о климатических и погодных условиях, данные гидрологических, метеорологических, океанографических наблюдений, информация, полученная в результате научно-исследовательских работ и инженерных изысканий, в которых принимали участие авторы, а также сведения из литературных источников. Картографирование в геоинформационной среде позволило создать тематические карты, отражающие динамику гидрометеорологических процессов. Полученная информация использовалась при построении моделей циркуляции вод, становления и деградации ледяного покрова в проливе Невельского с применением геоинформационных технологий. Авторы принимали непосредственное участие в исследованиях створа «Новый» в 2001 г. В результате изучения особенностей гидрометеорологических условий в пределах акватории пролива Невельского и его побережий, основанных на данных спутникового мониторинга, наблюдений на близлежащих метеостанциях, а также подтвержденных информацией, полученной во время изысканий, установлено, что в районе пролива Невельского неблагоприятные явления природы следует учесть при принятии технических проектных решений по выбору типа мостового или тоннельного перехода с материка на Сахалин. Пространственно-временное распределение сияния в районе обусловлено астрономическими причинами, а снижение продолжительности солнечного сияния в Де-Кастри и Погиби по сравнению с Николаевском-на-Амуре связано с частыми туманами, возникающими при атмосферных процессах на границе суши и моря. Экстремальные значения температуры воздуха в Погиби зарегистрированы на метеостанции Погиби – максимум 27,3 °С и минимум – –44,0 °С. Индекс континентальности весьма высокий (амплитуда 71,3 °С), что можно объяснить влиянием выноса воздушных масс с материка в зимний период. Важный для проектирования показатель – продолжительность безморозного периода – колеблется в Погиби от 88 до 186 дней (среднее значение – 137). Суточные суммы осадков теплого периода достигали максимальных значений 88 мм в октябре, 81 – в августе и 78 – в июле. Снежный покров в Погиби держится от 153 до 216 дней. Ветер ≥30 м/с случается весной и осенью ежегодно, иногда превышает 40 м/с. Туманы в описываемом районе наблюдаются в течение всего года. Метели в проливе и на его берегах очень частое явление. Любое усиление ветра зимой сопровождается метелевым переносом снега. Грозы случаются 4–5 раз в году. Пыльные бури бывают редко. Горизонтальная циркуляция воды в северной части пролива зимой имеет антициклоническую направленность, с мая по сентябрь действует циклоническая циркуляция. В целом весной на поверхности скорости движения вод составляют 2–7 см/с, а летом уменьшаются до 1–4 см/с. Изменения уровня моря в Татарском проливе находятся в диапазоне 3,2–4 м. Продолжительность ледового периода в умеренные типы зим составляет 201 сут. Толщина припая в Погиби в конце марта –начале апреля в среднем составляет 160 см и варьирует от 119 до 190 см в зависимости от типа зимы. Из-за сильных приливных течений сплошной ледяной покров в канале средней части пролива формируется крайне редко и на непродолжительное время. Следствием повышенной динамики ледяного покрова является многократное наслоение молодых льдов толщиной до 30 см. Берега в южной части пролива обладают устойчивостью к абразионным процессам и практически не разрушаются. Результаты изучения климатических и гидрологических условий показали, что строительство мостового перехода в проливе Невельского возможно. Наиболее благоприятными условиями для строительства сооружения обладает район, заключенный между линиями створов м. Лазарева – м. Погиби на севере и м. Южный – м. Тык на юге, климатические и гидрологические условия на всем протяжении имеют относительное сходство, что позволило нам выделить его при районировании как самостоятельную единицу. Выполненные исследования позволяют отдать преимущество створу «Новый» (м. Невельского – м. Лах).

Breeding Biology of Freshwater Goby Glossogobius Giuris Using Gonadosomatic Index and Gonadal Histology

The breeding season of fishes plays an important role in fish domestication and conservation of fish diversity. Freshwater goby, Glossogobius giuris is an important food fish of Bangladesh. Therefore, a study was performed to determine the breeding biology through assessing the gonadosomatic index (IG), fecundity and histology of gonad of G. giuris. A total of 1371 females and 1051 male fishes were collected from the Belai beel of Gazipur district. Significantly (P<0.05) higher values of mean IG were observed during March and from June to August for both females and males. The highest mean fecundity was recorded in August and the lowest was recorded in May. The smallest mean oocyte length was 0.037±0.005 mm in May and the largest was 0.071±0.001 mm in August. The early and late perinucleolar stages of oocytes were observed from January to March. The yolk vesicle stage was observed during April to May and yolk granule stage was observed during March and from June to August. These results revealed that G. giuris might breed in March and from June to August.
 Ann. Bangladesh Agric. (2019) 23(1) : 1-13

Quantifying evapotranspiration and crop coefficients for cotton (Gossypium hirsutum L.) using an eddy covariance approach

Accurate quantification of consumptive water requirements (ETc, evapotranspiration) of cropping systems is a critical prerequisite for sustainable irrigation water management applications. For applying the ETc for irrigation scheduling across soils and climates other than the location in which it was measured, it is also critical to develop crop coefficients (Kc) that link a reference crop evapotranspiration computed from local weather data to ETc. A systematic study for deriving Kc for cotton (Gossypium hirsutum L.) - representing its growth stages from planting to harvest - in humid climates is lacking in the literature. In this study, we used an eddy covariance (EC) method to quantify ETc from irrigated cotton (Gossypium hirsutum L.) in a 250 ha field with a Tunica clay soil, in 2017 and 2018. In the EC experiment, an open-path infrared gas analyzer and a sonic 3-D anemometer were deployed in the constant flux layer above the cotton canopy for collecting crop-canopy water flux data. Using the measured ETc, Kc were derived for alfalfa (Kcr) and grass (Kco) reference crop ET computed from weather data. Cotton cv. Delta Pine Land 1522 was planted in the first week of May and harvested in the second week of September in both the years. Lint yield was 1269 kg ha−1 in 2017 and 1569 kg ha−1 in 2018. Measured monthly averaged daily ETc ranged between 2.5 mm in May/September to 4 mm in July in 2017, and between 2.9 mm in May and 4.4 mm in August in 2018. Maximum daily ETc in 2017 and 2018 crop seasons were 5.6 and 6.7 mm, respectively. Seasonal total ETc was 367 mm and 439 mm (on average 402 mm), respectively. Alfalfa (ETr) and grass reference crop ET (ETo) computed were 664 and 546 mm, respectively. Averaged across the two years, average daily Kcr ranged between 0.45 in May to 0.80 in August, and Kco ranged from 0.54 in May and 0.99 in August. On average, seasonal ETr was 18 % more than ETo. Seasonal ETr and ETo were, respectively, 39 % and 22 % more than ETc. The Kc data developed will be useful for irrigation scheduling in cotton grown in similar climates and soils.

Assessing the Need of Pre-germination Anaerobic Stress-Tolerant Varieties in Indian Soybean (Glycine max (L.) Merrill)

In the wake of unprecedented extreme precipitation scenario, this paper attempts to evaluate the need of breeding efforts to develop soybean ideotypes for moisture extremes in case of excessive rainfall in highly productive soybean areas of India. During the monsoon months, the decadal rainfall analysis in selected high soybean-producing districts of Madhya Pradesh (highest rainfall 350.27 mm in July), Maharashtra (highest rainfall 223.73 mm in July) and Rajasthan (highest rainfall 290.06 mm in August) indicated that the crop has every chance to get exposed to waterlogging stress in its initial stages of germination (pre-germination) and initial seedling establishment, thereby adversely affecting the vegetative phase of the crop. Hence, genetic enhancement of soybean through tolerant varieties/cultivars to pre-germination anaerobic stress should be a viable strategy to overcome waterlogging in any case, providing good yield to soybean producers.

Temperature and rainfall trend analysis at monthly scale in Dehradun District, Uttarakhand using variance corrected mann- kendall test

The climate variability trends in temperature and precipitation have tremendous effects on many future studies. Analysing the time-series properties of climate simulation modelling simulations offers the advantages of knowing the experimental design on which models were generated. This article addresses the two methodological aspects of time series analysis. The 20th-century climatic patterns were studied for all the 12 months (January- December) period separately. Our results show that there was a statistically significant change in the pattern of three weather parameters viz. rainfall, Tmax, Tmin during 1901-2002 in Dehradun District, Uttarakhand. The monthly rainfall trend in January and August period found to be decreasing and overall average reduction in rainfall amount 7.446 mm in January and 18.87 mm in August was observed during 102 years (1901-2002) periods. The increasing linear trend was observed during March and May months. The overall average increases in rainfall amount were 6.834 mm in March and 6.528 mm in May during 102 years (1901- 2002) period. Modified MK test was applied to monthly rainfall data (mm) from January to December month period, downward linear trend (p<0.05) observed for the January and August (Tau <0) of magnitude Sen’s slope -0.073 and -0.185 and intercept 26.98 and 254.91, respectively. The key findings of this study may be helpful for planning and managing seasonal and annual studies to policymakers/ planners/agricultural field workers for advising some policies to cope with anticipated climate variability and climate change.

Analysis of Runoff and Sediment Yield Characteristics in Small Watershed of Taihang Mountain Area

With the small watershed of Chongling in the Taihang Mountain area as the study area, and with the experimental data of the watershed test base collected for years, this paper studies the characteristics of rainfall, runoff and sediment yield of this area. The results show that the adequacy and inadequacy of rainfall in the study area was alternate from 1959 to 2017, and the interannual changes were large, showing non-significant trend of annual rainfall. Vegetation cover can retain surface runoff. When the rainfall was below 250mm in August, the runoff after afforestation was significantly reduced. When the rainfall was over 250mm in August, the runoff quantity changes before and after afforestation were not significant.

Pluvial conditions in Wroclaw, Poland

The paper presents rainfall conditions for the city of Wroclaw (Poland) in the multi-annual period 1960–2017. A decreasing tendency of annual precipitation totals on the level of –12.5 mm/decade and decreasing trend of the monthly total in November of –2.9 mm/decade has been shown. In remaining months, no statistically significant change trends were observed. The maximum daily rainfall amounts were recorded in summer months: 56.4 mm in June, 74.4 mm in July and 67.5 mm in August. The analysis of variability in the number of precipitation with daily amounts exceeding 10 mm showed statistically significant decreasing trends – a decrease in the number of days in the amount of 0.69 per decade (linear regression). In the case of rainfall exceeding 20 mm and 30 mm no statistically significant trends were noted – the number of days with such heavy precipitation is practically constant and amounts to an average of 3.84 and 1.44 precipitation per year.

Formation and influencing factors of dew in sparse elm woods and grassland in a semi-arid area

Dew is a significant source of available water in arid and semi-arid regions, and it is considered as being the primary water source that supports living things in extreme arid regions. The objective of the present study was to determine temporal and spatial variation and the influencing factors of dew in natural sparse elm woods and grassland in Hunshandak Sandland, Inner Mongolia. One of the goals of this study was to quantify dew accumulation and duration in different types of vegetation based ecosystems. Dew formation, duration, accumulation, and environmental factors were continuously measured from the end of July to early October, 2014 during the growing season utilizing the weighing method and condensation surface technique. Leaf surfaces of the natural ecosystem were used as the condensation surfaces and served as a tool to determine the atmospheric condensation water on the plant leaves. PVC tubes with undisturbed soil were weighed before being placed into the soil at night and were reweighed before sunrise the next morning to determine dew formation in the soil from both atmospheric and deep soil layer condensation. The experiment was conducted from July 22 to October 10, 2014 and there were 43days of dew formation during this time. Daily dew duration was averagely 4.04h and 5.69h in sparse elm woods and grassland, respectively, and daily dew accumulation was 0.12mm and 0.24mm, respectively. The total dew accumulation was 1.44mm in sparse elm woods and 5.95mm in the grassland ecosystem. Dew accumulation was significantly higher in grassland than in sparse elm woods (p=0.029). Daily dew accumulation was the highest in July, with a value of 0.11mm, followed by 0.10 mm and 0.03mm in August and September, respectively, for sparse elm woods, while the highest value for grassland was 0.26mm in July, followed by 0.22mm, 0.16mm, and 0.12mm in August, September, and October. Soil dew mainly depended on the water vapor arising from the deep soil layers, rather than atmospheric water vapor. The highest values occurred in September and were 0.29mm and 0.35mm in sparse elm woods and grassland. Soil displayed water vapor lost to the atmosphere and the evaporation of soil was larger than the amount of condensation even at night, which was due to higher soil temperature in the upper 5cm soil layer than that of the air temperature. Soil water evaporation also provided a large amount of water vapor for atmospheric dew, and enhanced by increasing relative air humidity near the ground surface. Dew was largely affected by air temperature and relative air humidity in both sparse elm woods and grassland, followed by wind speed. Dew accumulation increased with rising relative air humidity. In conclusion, dew was a variable water source and was affected by multiple factors, not only climatic factors but also vegetation coverage. Dew accumulation and duration were lower under sparse elm wood canopies than in grassland.

Water Use Dynamics of Peach Trees under Postharvest Deficit Irrigation

Postharvest deficit irrigation is a potential strategy for conserving valuable fresh water for production of early season tree fruit crops such as peaches. However, water use dynamics under deficit irrigation conditions that can be described as seasonal changes in crop evapotranspiration (ETc) and crop coefficient (Kc) are largely unknown. A three-year field study was carried out in a 1.6 ha peach orchard to determine seasonal ETc and Kc characteristics. The orchard was divided equally into 72 plots, in which 12 randomly selected plots received deficit irrigation and the remaining 60 plots received full irrigation. A Bowen ratio flux tower was installed in the orchard to make meteorological measurements for estimating an integrated ETc for the orchard. The study showed that from July to August 75-85% of the daily net radiation was used by latent heat or partitioned into ETc. The average monthly cumulative ETc was 151 mm in June, 162 mm in July, and 155 mm in August. Kc values under deficit irrigation conditions or termed as Deficit_Kc was computed as ratios of the ETc over potential evapotranspiration or ETo, and were compared with Kc derived from a lysimeter study under non-water stressed conditions or termed as Lysimeter_Kc. The maximum Deficit_Kc values were 0.90, 1.03, and 1.07 for the three field seasons but all were smaller than 1.20, the maximum Lysimeter_Kc. The study demonstrated that water stress under deficit irrigation can be characterized in Kc values. The approach may be used to detect if portions of an orchard or the entire orchard are under water stress. Conversely, the method may provide guidance on deploying deficit irrigation practices with pre-determined Deficit_Kc.

Prey availability and selective feeding of sea trout (Salmo trutta L., 1758) fry stocked in small forest streams

Summary The food base and stomach contents of stocked sea trout (Salmo trutta) fry were determined in the first 4 months (April–August 2010) of life in two small lowland streams after resorption of the yolk sac. In each stream, 600 individual trout were released in a 200 m stocking-section. The macrozoobenthos given as a food base for the fry were collected once a month from the streams using a bottom scraper. Three subsamples of macrozoobentos were considered as one sample from the stocking-section. On the same day, 50 stocked fry were captured in each stream using electric fishing gear. Preferred food components were usually the taxa represented by number in a given stream in a particular month. Width size range of the prey in fish stomachs in May was from 0.10 to 1.47 mm, and from 0.11 to 3.78 mm in August. All food items found in both streams during the study months were also represented in intensity in the fish: Cyclopoida, and larvae of Baetidae and Chironomidae. Almost all Helodidae and Simuliidae larvae as well as the majority of Limoniidae and Nemouridae larvae were available as food each month.

『각사등록』에 의한 조선시대 경기도지역 측우기 우량 관측자료 복원 및 분석(1830~1893)

Chugugi and Wootaeck rainfall data of Gyeonggi Province from 1830 to 1893 were restored from the "Gaksadeungnok" that is the government records between the central government and the local during the Joseon Dynasty. The restored data periods were 27, 10, 9 and 14 years for Kwangju, Suwon, Ganghwa and Gaeseong, and the total number of restored data was 655 for the Chugugi and 427 for the Wootaek, respectively. The variation pattern of monthly rainfall by Chugugi was investigated and it showed that the monthly rainfall more than 300 mm was recorded 25 times with 18 times in July, 5 times in August and 3 times in June. The cases of more than 500 mm were also recorded 8 times with the maximum 787 mm at the Kwangju in July 1862, showing the similar pattern to Seoul. The monthly mean rainfall for the Gyeonggi Province were 259 mm in July, 204 mm in August and 121 mm in June, which were about one third of that of Seoul. The correlation analysis between the Chugugi and Wootaek data was carried out to derive the quantitative values of Wootaek observations. It revealed that 1 'Ri' of Wootaek observation was equal to approximately 1 'Chon (Chugugi unit)' or 20 mm, while 1 'Seo' was very variable between 2 and 6 'Boon (Chugugi unit)' with the median value approximately 3 'Boon' or 6 mm. Recalculated Wootaek data showed that the monthly rainfall in July, August, and June were 289 mm, 154 mm, and 124 mm, respectively. Through this study, some features of the rainfall variation pattern during 1830~1893 were figured out, and quantitative interpretation of Wootaek data became possible based on the restored rainfall data from the "Gaksadeungnok". Though many pages of the book have been lost during the last hundreds years, "Gaksadeungnok" is still very meaningful and of practical use, for it contains plenty of the local data throughout the whole country during the latter part of Joseon Dynasty. Therefore, further studies are strongly recommended on the restoration of climate related data and on the climatic tendency of 19th century of Korean peninsular.

Influence Nonuniformity of the Atmospheric Water Vapor Field on the Phase Measurements of Radio Signals from Global Navigation Satellite Systems

We present the experimental results for the horizontal gradients of integrated content of atmospheric water vapor, which are retrieved from the phase measurements of signals in the receiver network of the global navigation satellite systems in 2011 in the Republic of Tatarstan. The seasonal gradient variation is found. The meridional gradient usually shows a decrease in integrated water vapor with increasing latitude, and its monthly mean values are equal to −1.8 mm and 0.1 mm of precipitable water per 100 km in August and December, respectively. The zonal monthly average gradient is somewhat smaller in magnitude than the meridional one and is equal 0.1 mm and −0.8 mm per 100 km in March/June and May/October, respectively. Instantaneous values of the gradients can by an order of magnitude higher than the monthly mean values. Contribution from the gradient of integral water vapor to the phase-measurement difference between two antennas spaced 30 km apart is shown to attain its maximum of 141.5 mm in August for the zenith angle 80°. Errors in determining the mutual location of the ground-based antennas of global navigation satellite systems due to the water vapor gradients can reach 66 mm and 16.9 mm in August and February, respectively.

Chemical characterization of rainwater over Suwon region during farming and non-farming periods

Recently, special attention has been givento acid rain and its problem to environment such as acid precipitation and air pollution in East Asia.In the present study, rainwater samples werecollected from Apr to Oct (farming period) and from Nov to Mar (non-farming period) in 2009 ~ 2011. The samples were chemically characterized for the assessment of emission sources. Suwon region, a typical agricultural area in Gyeonggi province (South Korea) was chosen as a study site. The content of ionic species and theirtemporal variation were used forfactor analysis, which was used to presume the natural and anthropogenic sources depending upon the farming and non-farming periods. The cationsobserved during farming and non-farming periods were > Na+> Ca2+> K+> H+> Mg2+and Na+> N >Ca2+> H+= Mg2+> K+, respectively. The anions during farming and non-farming periods were > > Cl- and > > Cl-, respectively. While the amounts of sulfate, one of the major dissolved components of rainwater were 113.5 and 177.0 ueq.L-1, the ones of NSS- (Non-Sea Salt sulfate) were 93.7 and 87.1% during farming and non-farming periods, respectively. The comparison of observed pH values (pHobs) with the theoretical pH values (pHthe) showed that the neutralization of rainwater considerably went along during farming and non-farming periods. The highest amountof rainfall throughout the year was310.5 mmin August and its corre sponding nitrogen loading was5.03 kg·ha-1. The major ion contents for crop growth, , Ca2+, K+, Mg2+, were 49.4, 5.5, 18.1,1.4 kg·ha-1from April to October. The major contributions to the existing chemical ions in rainwaters during farming and non-farming periods were from the natural sources (sea and soil) and the anthropogenic sources (human and animal waste, vehicular emission + fossil fuels combustion), respectively.

Susceptibility of Pinus nigra and Cedrus libani to Turkish Gremmeniella abietina isolates

Gremmeniella abietina causes shoot dieback and stem cankers on conifers throughout Northern hemisphere. The aim of this study was to investigate the virulence of Turkish G. abietina isolates in a field experiment. The lower branches of 15-20-year-old P. nigra and C. libani in a plantation site at 1,050 m a.s.l. in Isparta were inoculated at 1-2-month intervals during September-January. Five isolates obtained from high altitude mountainous forests were used. Each isolate was inoculated into two branches per tree and repeated ten times on both tree species at each inoculation date. The branches were sampled at the end of February, and in August, and lesion lengths in the inner bark measured. The mean lesion length on P. nigra and C libani were 10.6 ± 0.8 and 3.8 ± 0.2 mm in February and 17.6 ± 1.4 and 7.8 ± 0.8 mm in August, respectively. Differences in the mean lesion length between the isolates were small. Nevertheless, there were significant differences between the isolates on P. nigra in November and January inoculations, and on C. libani at all four inoculation times. The mean lesion lengths for all isolates at both sampling dates was the highest (p &lt; 0.01) in December inoculations for both P. nigra (22.0 ± 1.9 February; 32.9 ± 2.9 August) and C. libani (5.6 ± 0.7; 11.3 ± 1.2). There was no difference between the September and January inoculations on P. nigra, despite the almost six-fold difference in incubation period. During the December inoculations, the trees were most likely in winter dormancy, i.e. unable to defend themselves, which would explain the large lesions.