Long-term photoacclimation ofHaslea ostrearia(Bacillariophyta): effect of irradiance on growth rates, pigment content and photosynthesis

The problem of the Russian economy’s growth rates is considered in the article in the context of Russia’s backwardness regarding GDP per capita in comparison with the developed countries. The author stresses the urgency of modernization of the real sector of the economy and the recovery of the country’s human capital. For reaching these goals short- or mid-term programs are not sufficient. Economic policy needs a long-term (15-20 years) strategy, otherwise Russia will be condemned to economic inertia and multiplying structural disproportions.

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Adjacency to a harvest trail increases drought resistance of interior Douglas-fir (Pseudotsuga menziesii var. glauca) in partially harvested stands in central British Columbia

Canadian Journal of Forest Research ◽

10.1139/cjfr-2018-0007 ◽

2018 ◽

Vol 48 (7) ◽

pp. 809-820 ◽

Cited By ~ 1

Author(s):

Neil P. Thompson ◽

Kathy J. Lewis ◽

Lisa M. Poirier

Keyword(s):

British Columbia ◽

Drought Tolerance ◽

Pseudotsuga Menziesii ◽

Growth Rates ◽

Habitat Management ◽

Odocoileus Hemionus ◽

Douglas Fir ◽

Ring Analysis ◽

The Relationship

Drought tolerance of trees may be affected by competition, but most studies quantifying the relationship do not consider the effect of stem clustering. Trees are often clustered in interior Douglas-fir (Pseudotsuga menziesii var. glauca (Mayr) Franco) forests near the grassland interface in central British Columbia due to past harvesting practices or habitat management for mule deer (Odocoileus hemionus hemionus (Rafinesque, 1817)). Climate change projections indicate continued increases in temperature, an outcome that would stress trees growing in dry environments. Trees placed in different states of competition by mechanical harvesting in the 1970s were sampled to provide a 40-year comparison of three levels of competition during 1–2 year droughts. Tree-ring analysis was used to assess the reduction in growth during drought years and resumption of growth in subsequent years. A clear separation of growth rates was evident between open-growing trees, trees on the edge of harvesting trails, and trees within the unharvested interior. Edge trees had intermediate growth rates but no differences were found in the long-term climate–growth relationship compared with open-growing trees. Both Edge and Open classes showed less relative growth reduction during droughts than Interior trees growing between harvest trails. Precipitation throughfall rates and competition for resources are likely driving short-term drought tolerance in combination with other factors.

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Seasonal patterns of pasture production in the Bay of Plenty and Waikato

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1991.53.2007 ◽

1991 ◽

pp. 67-72

Author(s):

J.A. Baars ◽

G.J. Goold ◽

M.F. Hawke ◽

P.J. Kilgarriff ◽

M.D. Rolm

Keyword(s):

Growth Rates ◽

Early Spring ◽

Early Summer ◽

Growth Patterns ◽

Climatic Data ◽

Large Contribution ◽

Pasture Production ◽

Summer Peak ◽

The Difference

Patterns of pasture growth were measured on 3 farms in the Bay of Plenty (BOP) and at No2 Dairy (Ruakura Agricultural Centre) in the Waikato from 1989 to 199 1. A standardised trim technique with cages and 4-weekly cutting under grazing was used. Long-term seasonal growth patterns, using a predictive pasture model, were also simulated. Simulated pasture growth from long-term climatic data shows that pasture growth rates are higher in winter, early spring and late autumn in the BOP than the Waikato. However, the actual measurements over the 2 years show that pasture growth over the latter periods is lower at the BOP sites than at the Waikato site. In the BOP the spring peak is much later than in the Waikato while an early summer peak, with higher growth rates than in the Waikato, occurred in the BOP. No such summer peak was evident in the Waikato. The difference between the two regions is caused by the large contribution of subtropical grasses to sward production in summer and autumn, The prolific summer growth of subtropical grasses may explain the low ryegrass content and low pasture production in winter. The lower than expected autumn, winter, spring production may also becaused by low clover content, possibly a result of competition from subtropical grasses and a sulphur deficiency. The apparent low amount of nitrogen fixed by clover may explain the low rates of pasture production over the cooler season. Applications of nitrogen fertiliser may substantially increase dry matter production from April to September. Keywords pasture,simulation,subtropical grasses, Paspalum, Digitaria sanguinalis, growth rates

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An Evaluation of RNA–DNA Ratio as a Measure of Long-Term Growth in Fish Populations

Journal of the Fisheries Research Board of Canada ◽

10.1139/f73-035 ◽

1973 ◽

Vol 30 (2) ◽

pp. 195-199 ◽

Cited By ~ 69

Author(s):

Terry A. Haines

Keyword(s):

Growth Rate ◽

Population Growth ◽

Growth Rates ◽

Population Growth Rate ◽

Environmental Changes ◽

Age Distribution ◽

Smallmouth Bass ◽

Fish Populations ◽

Population Growth Rates

The value of RNA–DNA ratio as a measure of long-term growth of fish populations under semi-natural conditions and when subjected to environmental manipulations was determined. Populations of carp and smallmouth bass of known age distribution were established in artificial ponds maintained at two fertility levels. After 15 months, population growth rates (as percent increase in weight) and RNA–DNA ratios of muscle tissue from selected fish were measured. Each species exhibited a range of population growth rates. The relation between population growth rate and individual fish RNA–DNA ratio for each species was significant. When reproduction occurred, the relation was not significant unless young-of-the-year fish were excluded from population growth rate calculations. Age of fish was also found to have an important effect on RNA–DNA ratio, with the ratio being higher in younger fish.RNA–DNA ratio can be a reliable indicator of long-term population growth in fish when population age structure is known and recruitment is controlled. The method has potential for use in detecting response to environmental changes before growth rate changes become severe.

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Long-term historical trends in air pollutant emissions in Asia: Regional Emission inventory in ASia (REAS) version 3.1

10.5194/acp-2019-1122 ◽

2019 ◽

Cited By ~ 8

Author(s):

Junichi Kurokawa ◽

Toshimasa Ohara

Keyword(s):

Economic Growth ◽

Growth Rates ◽

Emission Inventory ◽

Air Pollutant ◽

Pollutant Emissions ◽

Anthropogenic Sources ◽

Gridded Data ◽

Relative Contribution ◽

The Republic

Abstract. A long-term historical emission inventory of air and climate pollutants in East, Southeast, and South Asia from 1950–2015 was developed as the Regional Emission inventory in ASia version 3.1 (REASv3.1). REASv3.1 provides details of emissions from major anthropogenic sources for each country and its sub-regions and also provides monthly gridded data with 0.25° × 0.25° resolution. The average total emissions in Asia during 1950–1955 and from 2010–2015 (growth rates in these 60 years) are as follows: SO2: 3.15 Tg, 42.4 Tg (13.5); NOx: 1.83 Tg, 47.6 Tg (26.0); CO: 62.2 Tg, 319 Tg (5.13); non-methane volatile organic compounds: 9.14 Tg, 61.8 Tg (6.77); NH3: 7.99 Tg, 31.3 Tg (3.92); CO2: 1.12 Pg, 18.3 Pg (16.3); PM10: 5.76 Tg, 28.4 Tg (4.92); PM2.5: 4.52 Tg, 20.3 Tg (4.50); black carbon: 0.751 Tg, 3.38 Tg (4.51); and organic carbon: 2.62 Tg, 6.92 Tg (2.64). Clearly, all the air pollutant emissions in Asia increased significantly during these six decades, but situations were different among countries and regions. Due to China's rapid economic growth in recent years, its relative contribution to emissions in Asia has been the largest. However, most pollutant species reached their peaks by 2015 and the growth rates of other species was found to be reduced or almost zero. On the other hand, air pollutant emissions from India showed an almost continuous increasing trend. As a result, the relative ratio of emissions of India to that of Asia have increased recently. The trend observed in Japan was different from the rest of Asia. In Japan, emissions increased rapidly during 1950s–1970s, which reflected the economic situation of the period; however, most emissions decreased from their peak values, which were approximately 40 years ago, due to the introduction of regulations and laws for air pollution. Similar features were found in the Republic of Korea and Taiwan. In the case of other Asian countries, air pollutant emissions generally showed an increase along with economic growth and motorization. Trends and spatial distribution of air pollutants in Asia are becoming complicated. Datasets of REASv3.1, including table of emissions by countries and sub-regions for major sectors and fuel types, and monthly gridded data with 0.25° × 0.25° resolution for major source categories are available through the following URL: http://www.nies.go.jp/REAS/.

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Carcass additions increase juvenile salmonid growth, condition, and size in an interior Columbia River Basin tributary

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2019-0215 ◽

2020 ◽

Vol 77 (4) ◽

pp. 703-715 ◽

Cited By ~ 3

Author(s):

Matthew J. Kaylor ◽

Seth M. White ◽

Edwin R. Sedell ◽

Dana R. Warren

Keyword(s):

Body Size ◽

Growth Rates ◽

Life Histories ◽

Freshwater Ecosystems ◽

Steelhead Trout ◽

Juvenile Salmonids ◽

Early Fall ◽

Juvenile Chinook ◽

The Relationship

Numbers of anadromous fish returning to freshwater ecosystems have declined precipitously across much of western North America, reducing a potentially important resource subsidy for juvenile salmonids. We added carcasses to three sections of a Snake River tributary and assessed juvenile Chinook salmon (Oncorhynchus tshawytcha) and steelhead trout (Oncorhynchus mykiss) growth, body condition, size, and diet responses in summer and early fall. Juvenile salmonids consumed an abundance of eggs and carcass tissue, which increased energy rations. Within 3 weeks of carcass additions, juvenile Chinook and steelhead growth rates were 1.1–5 and 6–23 times greater in treatment reaches relative to control reaches, respectively. We used long-term tagging and detection data from this system to assess the relationship between juvenile Chinook size and emigration survival for two different juvenile life histories. The increased growth rates and body size in response to carcass additions, coupled with a positive relationship between body size and survival, suggest that juvenile salmonid rearing productivity and emigration survival may be limited by depressed returns of anadromous fishes in this system and potentially other tributaries of the Columbia Basin.

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Long-term passage of tachyzoites in tissue culture can attenuate virulence of Neospora caninum in vivo

Parasitology ◽

10.1017/s0031182006000539 ◽

2006 ◽

Vol 133 (4) ◽

pp. 421-432 ◽

Cited By ~ 47

Author(s):

P. M. BARTLEY ◽

S. WRIGHT ◽

J. SALES ◽

F. CHIANINI ◽

D. BUXTON ◽

...

Keyword(s):

Tissue Culture ◽

Body Weight ◽

Growth Rates ◽

Clinical Symptoms ◽

Neospora Caninum ◽

High Passage ◽

Low Passage

To determine whether prolonged in vitro passage would result in attenuation of virulence in vivo, Neospora caninum tachyzoites were passaged for different lengths of time in vitro and compared for their ability to cause disease in mice. Groups of Balb/c mice were inoculated intraperitoneally with 5×106 or 1×107 of low-passage or high-passage N. caninum tachyzoites. The mice were monitored for changes in their demeanour and body weight, and were culled when severe clinical symptoms of murine neosporosis were observed. Mice inoculated with the high-passage parasites survived longer (P<0·05), and showed fewer clinical symptoms of murine neosporosis, compared to the mice receiving the low-passage parasites. The parasite was detected in the brains of inoculated mice using immunohistochemistry and ITS1 PCR. Tissue cysts containing parasites were seen in mice inoculated with both low-passage and high-passage parasites. When the in vitro growth rates of the parasites were compared, the high-passage parasites initially multiplied more rapidly (P<0·001) than the low-passage parasites, suggesting that the high-passage parasites had become more adapted to tissue culture. These results would suggest that it is possible to attenuate the virulence of N. caninum tachyzoites in mice through prolonged in vitro passage.

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