Microsite Effects on Physiological Performance of Betula ermanii at and Beyond an Alpine Treeline Site on Changbai Mountain in Northeast China

The alpine treeline demarcates the temperature-limited upper elevational boundary of the tree life form. However, this treeline does not always occur exclusively as a sharp “line”, outposts of tree groups (OTG) with a height of at least 3 m are often observed in microsites up to several hundred meters beyond the line of continuous forest on some mountains. This suggests that other factors such as microenvironment may play a significant role in compensating for the alpine tree facing growth-limiting low temperature conditions. To test the microenvironment effects, this study compared the differences in growing conditions (climate and soil properties) and ecophysiological performance of Erman’s birch (Betula ermanii Cham.) trees growing in a continuous treeline site (CTL, ~1950 m above sea level, a.s.l.) and OTGs (~2050 m a.s.l.) on Changbai Mountain in northeastern China. The results show the average 2-m air temperature for OTG was slightly lower in the non-growing season than which at the CTL (−10.2 °C < −8.4 °C), there was no difference in growing season air temperature and soil temperature at 10 cm depth between CTL and OTG. The contents of focal soil nutrients in CTL and OTG were similar. Difference in K and Mn contents between sites were detected in leaves, difference in K, Mn, and Zn in shoots. However, comparing similarity of ecophysiological performances at an individual level, trees at CTL and OTG show no significant difference. Our study reveals that mature trees at the CTL and OTG experience generally similar environmental conditions (climate and soil properties) and exhibit similar overall ecophysiological performance (reflected in carbon reserves and nutrients). This might provide insight into how mature trees might be able to survive in areas higher than the continuous treeline, as well as the importance of microclimatic amelioration provided by protective microsites and the trees themselves.

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Prospects of practical use of new potatoes state varietal resources in the north-east Forest-Steppe of Ukraine

Bulletin of Sumy National Agrarian University. The series: Agronomy and Biology ◽

10.32845/agrobio.2019.4.3 ◽

2019 ◽

pp. 15-21 ◽

Cited By ~ 1

Author(s):

N.S. Kozhushko ◽

M.M. Sakhoshko ◽

M.G. Bashtovyi ◽

D.V. Smilyk ◽

V.I. Avramenko ◽

...

Keyword(s):

Starch Content ◽

Growing Season ◽

Potato Production ◽

Climatic Conditions ◽

Forest Steppe ◽

North East ◽

The North ◽

Significant Difference ◽

New Varieties ◽

Growing Conditions

According to statistic evaluation of the manifestation of signs of the economic suitability of state sort resources of 2019 registration potatoes when growing it in different agro-climatic conditions, a significant advantage of influence of the forest-steppe conditions was determined. Compared to Polesia the increase of yield rose for 4.1 t/ha or 18 % (НІР05 = 2.18, Ffact= 12.65 > F05 = 4.22) and the amount of trade potato for 22.72 ha or 20 % (Ffact = 58.87). There is also a tendency to increase the number of starch from unit of area for – 17 % and the total consumer properties for – 8 %. However, there is a significant difference in the reduction of storability of products by 45 % and the lack of it’s resistance to macrosporiosis and late blight. It was proved that the yield of varieties for cultivation in the polesia zone by 25.7 % depended on the duration of the growing season (Ffact = 4.14 > F05 = 0.06). The relationship between yield and starch of potatoes in Polesia zone varieties was determined – 23.6 % and in forest-steppe – 17.3 % and starch collection, respectively, 33.6 % and 28.0 %. The dependence of storability of potato which grew in the polesia zone and in forest-steppe from the amount of starch for 15 % was mathematically proved (Ffact = 2.11 > F05 = 0.17) і 11.3 % (Ffact = 1.52 > F05 = 0.24); the dependence of storability on the duration of the growing season in the Forest-Steppe conditions was confirmed(Ffact = 0.66 > F05 = 0.43). In addition, the 12 % of tasting grade of the Forest-Steppe varieties depended on the starch content amount (Ffact = 1.65 > F05 = 0.22). According to the results of the regression analysis, mathematical models have been developed to predict yields, culinary and consumer properties, and the storability of new potato varieties under different growing conditions. The project of a conveyor for the consumption of fresh product in summer period with the involvement of varieties of early ripeness in the Forest-Steppe was presented: 80 days after planting – Sanibel, 90 days after planting – Medison, Paroli, 95 days after planting – Bazalia, Bernina, 100 days after planting – Donata, in the Polesia zone ‒ 80 days after planting – Sanibel, 90 days after planting – Paroli, 95 days after planting –Bazalia, 100 days after planting – Medison, Bernina, Donata. By distribution of varieties by predicted high content of phytonutrients there were bred varieties with red skin and creamy flesh – Bazalia and Sanibel, by high content with yellow flesh – Baltic Rosa and moderate content with white flesh – Oleksandrit, Fotynia, Ricarda. Introduction of new varieties with certain high adaptive potential of storability and content of bioactive compounds in potatoes will provide growth of potato production in the conditions of the northeast forest-steppe and increase its competitiveness in the domestic and foreign markets and will solve the problem of year-round consumption of fresh quality products.

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Short-term grazing exclusion has no impact on soil properties and nutrients of degraded alpine grassland in Tibet, China

Solid Earth ◽

10.5194/se-6-1195-2015 ◽

2015 ◽

Vol 6 (4) ◽

pp. 1195-1205 ◽

Cited By ~ 65

Author(s):

X. Lu ◽

Y. Yan ◽

J. Sun ◽

X. Zhang ◽

Y. Chen ◽

...

Keyword(s):

Soil Properties ◽

Soil Quality ◽

Growing Season ◽

Available Phosphorus ◽

The Tibetan Plateau ◽

Alpine Grasslands ◽

Short Term ◽

Available Nitrogen ◽

Grazing Exclusion ◽

Significant Difference

Abstract. Since the 1980s, alpine grasslands have been seriously degraded on the Tibetan Plateau. Grazing exclusion by fencing has been widely adopted to restore degraded grasslands. To clarify the effect of grazing exclusion on soil quality, we investigated soil properties and nutrients by comparing free-grazing (FG) and grazing exclusion (GE) grasslands in Tibet. Soil properties – including soil bulk density, pH, particle size distributions, and proportion of aggregates – showed no significant difference between FG and GE plots. Soil organic carbon, soil available nitrogen, and available phosphorus contents did not differ with grazing exclusion treatments in both the 0–15 and 15–30 cm layer. However, soil total nitrogen and total phosphorus contents were remarkably reduced due to grazing exclusion at 0–15 cm depth. Furthermore, growing season temperature and/or growing season precipitation had significant effects on almost all soil property and nutrient indicators. This study demonstrates that grazing exclusion had no impact on most soil properties and nutrients in Tibet. Additionally, the potential shift of climate conditions should be considered when recommending any policy designed for restoration of degraded soil in alpine grasslands in the future. Nevertheless, because the results of the present study come from a short-term (6–8 years) grazing exclusion, the assessments of the ecological effects of the grazing exclusion management strategy on soil quality of degraded alpine grasslands in Tibet still need long-term continued research.

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Land Uses, Altitude and Texture Effects on Soil Parameters. A Comparative Study in Two Districts of Nagaland, Northeast India

Agriculture ◽

10.3390/agriculture11020171 ◽

2021 ◽

Vol 11 (2) ◽

pp. 171

Author(s):

Gaurav Mishra ◽

Rosa Francaviglia

Keyword(s):

Soil Properties ◽

Soil Texture ◽

Soil Parameters ◽

Available Phosphorus ◽

Land Uses ◽

Management Options ◽

Available N ◽

P Content ◽

Significant Difference ◽

Soc Stocks

Northeast (NE) India is a typical tropical ecosystem with a luxuriant forest vegetation cover, but nowadays forests are under stress due to exploitation and land use changes, which are known to affect soil health and productivity. However, due to a scarcity of data, the influence of land uses and altitude on soil properties of this peculiar ecosystem is poorly quantified. This study presents the changes in soil properties in two districts of Nagaland (Mon and Zunheboto) in relation to land uses (forest, plantation, jhum and fallow jhum), altitude (<500 m, 500–1000 m, >1000 m) and soil texture (coarse, medium, fine). For this, a random soil sampling was performed in both the districts. Results indicated that soil organic carbon (SOC) stocks and available potassium (K) were significantly influenced by land uses in the Mon district, while in Zunheboto a significant difference was observed in available phosphorus (P) content. SOC stocks showed an increasing trend with elevation in both districts. The influence of altitude on P was significant and the maximum concentration was at lower elevations (<500 m). In Mon, soil texture significantly affected SOC stocks and the available N and P content. The variability in soil properties due to land uses, altitudinal gradients and textural classes can be better managed with the help of management options, which are still needed for this ecosystem.

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Comparison of Building Simulation Methods for Modeling Apartment Balconies

Energies ◽

10.3390/en14133955 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3955

Author(s):

Yonghan Ahn ◽

Hanbyeol Jang ◽

Junghyon Mun

Keyword(s):

Heat Transfer ◽

Air Temperature ◽

Parameter Analysis ◽

Interior Space ◽

Heating And Cooling ◽

Significant Difference ◽

Calculation Results ◽

Infiltration Parameter ◽

The Difference ◽

Heating And Cooling Load

The purpose of this study is to compare the load calculation results by a model using the air changes per hour (ACH) method and a model using an airflow network (AFN) and to ascertain what causes the difference between the two models. In the basic case study, the difference in the heat transfer distribution of the model in the interior space was investigated. The most significant difference between the two models is the heat transfer that results from infiltration. Parameter analysis was performed to investigate the relationship between the difference and the environmental variables. The result shows that the greater the difference is between the air temperature inside the balcony and the outdoor air temperature, and the greater the air flows from the balcony to the residential area, and the greater the heating and cooling load difference occurs. The analysis using the actual weather files of five domestic cities in South Korea rather than a virtual case shows that the differences are not so obvious when the wind blows at a constant speed throughout the year, but are dominant when the wind does not blow during the night and is stronger alongside the occurrence of sunlight during the day.

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Prospective associations between ECG abnormalities and death or myocardial infarction in a cohort of 980 employed, middle-aged Swedish men

The Egyptian Heart Journal ◽

10.1186/s43044-020-00114-9 ◽

2020 ◽

Vol 72 (1) ◽

Author(s):

Lennart Dimberg ◽

Bo Eriksson ◽

Per Enqvist

Keyword(s):

Myocardial Infarction ◽

Health Examination ◽

Individual Level ◽

Increased Risk ◽

Significant Difference ◽

Ethical Approval ◽

Independent Association ◽

Repeat Examination ◽

Normal Ecgs ◽

Ecg Abnormalities

Abstract Background In 1993, 1000 randomly selected employed Swedish men aged 45–50 years were invited to a nurse-led health examination with a survey on life style, fasting lab tests, and a 12-lead ECG. A repeat examination was offered in 1998. The ECGs were classified according to the Minnesota Code. Upon ethical approval, endpoints in terms of MI and death over 25 years were collected from Swedish national registers with the purpose of analyzing the independent association of ECG abnormalities as risk factors for myocardial infarction and death. Results Seventy-nine of 977 participants had at least one ECG abnormality 1993 or 1998. One hundred participants had a first MI over the 25 years. Odds ratio for having an MI in the group that had one or more ECG abnormality compared with the group with two normal ECGs was estimated to 3.16. 95%CI (1.74; 5.73), p value 0.0001. One hundred fifty-seven participants had died before 2019. For death, similarly no statistically significant difference was shown, OR 1.52, 95%CI (0.83; 2.76). Conclusions Our study suggests that presence of ST- and R-wave changes is associated with an independent 3–4-fold increased risk of MI after 25 years follow-up, but not of death. A 12-lead resting ECG should be included in any MI risk calculation on an individual level.

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Differences in warming impacts on wheat productivity among varieties released in different eras in North China

The Journal of Agricultural Science ◽

10.1017/s0021859615000118 ◽

2015 ◽

Vol 153 (8) ◽

pp. 1353-1364 ◽

Cited By ~ 4

Author(s):

C. Y. ZHENG ◽

J. CHEN ◽

Z. W. SONG ◽

A. X. DENG ◽

L. N. JIANG ◽

...

Keyword(s):

Winter Wheat ◽

Grain Yield ◽

Biomass Production ◽

Air Temperature ◽

North China ◽

Growth Period ◽

Wheat Breeding ◽

Wheat Growth ◽

Positive Effects ◽

Significant Difference

SUMMARYTen leading varieties of winter wheat released during 1950–2009 in North China were tested in a free-air temperature increase (FATI) facility. The FATI facility mimicked the local air temperature pattern well, with an increase of 1·1 °C in the daily mean temperature. For all the tested varieties, warming caused a significant reduction in the total length of wheat growth period by 5 days and especially in the pre-anthesis period, where it was reduced by 9 days. However, warming increased wheat biomass production and grain yield by 8·4 and 11·4%, respectively, on an average of all the tested varieties. There was no significant difference in the warming-led reduction in the entire growth period among the tested varieties. Interestingly, the warming-led increments in biomass production and grain yield increased along with the variety release year. Significantly higher warming-led increases in post-anthesis biomass production and 1000-grain weight were found in the new varieties compared to the old ones. Meanwhile, a significant improvement in plant productivity was noted due to wheat breeding during the past six decades, while no significant difference in the length of entire growth period was found among the varieties released in different eras. The results demonstrate that historical wheat breeding might have enhanced winter wheat productivity and adaptability through exploiting the positive effects rather than mitigating the negative impacts of warming on wheat growth in North China.

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Log landings are methane emission hotspots in managed forests

Canadian Journal of Forest Research ◽

10.1139/cjfr-2021-0109 ◽

2021 ◽

Author(s):

Juliana Vantellingen ◽

Sean C. Thomas

Keyword(s):

Organic Matter ◽

Soil Properties ◽

Management Practices ◽

Emission Rate ◽

Woody Debris ◽

Organic Matter Content ◽

Growing Season ◽

Matter Content ◽

Emission Rates ◽

Managed Forests

Log landings are areas within managed forests used to process and store felled trees prior to transport. Through their construction and use soil is removed or redistributed, compacted, and organic matter contents may be increased by incorporation of wood fragments. The effects of these changes to soil properties on methane (CH4) flux is unclear and unstudied. We quantified CH4 flux rates from year-old landings in Ontario, Canada, and examined spatial variability and relationships to soil properties within these sites. Landings emitted CH4 throughout the growing season; the average CH4 emission rate from log landings was 69.2 ± 12.8 nmol m-2 s-1 (26.2 ± 4.8 g CH4 C m-2 y-1), a rate comparable to CH4-emitting wetlands. Emission rates were correlated to soil pH, organic matter content and quantities of buried woody debris. These properties led to strong CH4 emissions, or “hotspots”, in certain areas of landings, particularly where processing of logs occurred and incorporated woody debris into the soil. At the forest level, emissions from landings were estimated to offset ~12% of CH4 consumption from soils within the harvest area, although making up only ~0.5% of the harvest area. Management practices to avoid or remediate these emissions should be developed as a priority measure in “climate-smart” forestry.

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The Street Air Warming Phenomenon in a High-Rise Compact City

Atmosphere ◽

10.3390/atmos9100402 ◽

2018 ◽

Vol 9 (10) ◽

pp. 402 ◽

Cited By ~ 4

Author(s):

Xiaoxue Wang ◽

Yuguo Li ◽

Xinyan Yang ◽

Pak Chan ◽

Janet Nichol ◽

...

Keyword(s):

Thermal Comfort ◽

Air Temperature ◽

Thermal Environment ◽

Urban Climate ◽

Pollutant Dispersion ◽

Urban Morphology ◽

Air Temperatures ◽

Significant Difference ◽

Sensitivity Studies ◽

Weather Stations

The street thermal environment is important for thermal comfort, urban climate and pollutant dispersion. A 24-h vehicle traverse study was conducted over the Kowloon Peninsula of Hong Kong in summer, with each measurement period consisting of 2–3 full days. The data covered a total of 158 loops in 198 h along the route on sunny days. The measured data were averaged by three methods (direct average, FFT filter and interpolated by the piecewise cubic Hermite interpolation). The average street air temperatures were found to be 1–3 °C higher than those recorded at nearby fixed weather stations. The street warming phenomenon observed in the study has substantial implications as usually urban heat island (UHI) intensity is estimated from measurement at fixed weather stations, and therefore the UHI intensity in the built areas of the city may have been underestimated. This significant difference is of interest for studies on outdoor air temperature, thermal comfort, urban environment and pollutant dispersion. The differences were simulated by an improved one-dimensional temperature model (ZERO-CAT) using different urban morphology parameters. The model can correct the underestimation of street air temperature. Further sensitivity studies show that the building arrangement in the daytime and nighttime plays different roles for air temperature in the street. City designers can choose different parameters based on their purpose.

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Air versus water temperature of aquatic habitats in Delhi: Implications for transmission dynamics of Aedes aegypti

Geospatial health ◽

10.4081/gh.2018.707 ◽

2018 ◽

Vol 13 (2) ◽

Cited By ~ 2

Author(s):

Gaurav Kumar ◽

Veena Pande ◽

Shweta Pasi ◽

Vijay P. Ojha ◽

Ramesh C. Dhiman

Keyword(s):

Water Temperature ◽

Air Temperature ◽

Data Loggers ◽

Breeding Habitats ◽

Significant Difference ◽

The Difference ◽

Near Future ◽

Plastic Containers ◽

Local Weather ◽

Container Material

The present study was planned to characterize the microclimate experienced by Aedes larvae in different breeding habitats by determining the temperature variations in water kept in containers during different months under natural conditions. The study was conducted in three municipal zones of Delhi. In each site, four types of container material (plastic, cement, iron and ceramic) were chosen for recording the water temperature in the containers. Daily air and water temperatures (mean, maximum and minimum values) recorded by HOBO and Tidbit data loggers, respectively, were compared using analysis of variance and Tukey’s honest significant difference (HSD) tests. Mean monthly temperature of water varied from 16.9 to 33.0 °C in tin containers, 17.3 to 35.6°C in plastic containers, 14.3 to 28.5°C in ceramic pots, 23.3 to 30.4°C in cemented underground tanks (UGT) and 15.8 to 35.1°C in cemented overhead tanks (OHTs). Corresponding values for the air temperature ranged from 17.7 to 36.1°C. The difference between temperature of water in the containers and air temperature was highest for ceramic pots. Daily mean, maximum and minimum temperatures recorded by different data loggers differed significantly (P<0.05). When Tukey HSD test was applied for data analysis, the daily mean air temperature differed significantly from the water temperature in tin and ceramic pots as well as cemented OHTs. The temperature of water in the different breeding habitats investigated was lower than the air temperature. Moreover, actual air temperature as recorded by HOBO was higher than the temperature recorded by local weather stations. Considering the ongoing climate change, cemented UGT and earthen pots may be more productive breeding habitats for the Aedes mosquito in the near future, while plastic and cemented OHTs might no longer be suitable for Aedes breeding.

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Seasonal dynamics of methane emissions from a subarctic fen in the Hudson Bay Lowlands

Biogeosciences ◽

10.5194/bg-10-4465-2013 ◽

2013 ◽

Vol 10 (7) ◽

pp. 4465-4479 ◽

Cited By ~ 19

Author(s):

K. L. Hanis ◽

M. Tenuta ◽

B. D. Amiro ◽

T. N. Papakyriakou

Keyword(s):

Soil Temperature ◽

Air Temperature ◽

Growing Season ◽

Near Surface ◽

Growing Seasons ◽

Air Temperatures ◽

Soil Temperatures ◽

Surface Soil Temperature ◽

Filling Method ◽

Highly Correlated

Abstract. Ecosystem-scale methane (CH4) flux (FCH4) over a subarctic fen at Churchill, Manitoba, Canada was measured to understand the magnitude of emissions during spring and fall shoulder seasons, and the growing season in relation to physical and biological conditions. FCH4 was measured using eddy covariance with a closed-path analyser in four years (2008–2011). Cumulative measured annual FCH4 (shoulder plus growing seasons) ranged from 3.0 to 9.6 g CH4 m−2 yr−1 among the four study years, with a mean of 6.5 to 7.1 g CH4 m−2 yr−1 depending upon gap-filling method. Soil temperatures to depths of 50 cm and air temperature were highly correlated with FCH4, with near-surface soil temperature at 5 cm most correlated across spring, fall, and the shoulder and growing seasons. The response of FCH4 to soil temperature at the 5 cm depth and air temperature was more than double in spring to that of fall. Emission episodes were generally not observed during spring thaw. Growing season emissions also depended upon soil and air temperatures but the water table also exerted influence, with FCH4 highest when water was 2–13 cm below and lowest when it was at or above the mean peat surface.

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