scholarly journals Pengaruh Kerapatan Vegetasi Terhadap Produktivitas Serasah Hutan Taman Nasional Gunung Leuser

Elkawnie ◽  
2017 ◽  
Vol 3 (2) ◽  
Author(s):  
Sri Jayanthi ◽  
Zulfan Arico
Keyword(s):  
High Density ◽  
Biological Factor ◽  
Systematic Sampling ◽  
Line Transect ◽  
Vegetation Density ◽  
Location Determination ◽  
Aceh Province ◽  
Chemical Content ◽  
Chemical Factors ◽  
Physical And Chemical

The research was conducted in January-September 2017 and will continue until December 2017 at Gunung Leuser National Park Resort Tenggulun, Aceh Tamiang District, Aceh Province. The method used to determine the vegetation density is purposive sampling by using a combination of line method and the method of with 20 m x 20 m. For determination of litter productivity by using Litter Trap method, and to analyze physical and chemical content of soil by laboratory test and calculate soil fauna density (biological factor) location determination by using line transect along 100 m, then on every line taken 10 point by method Systematic Sampling is systematically on the 3 (three) research sites that have been determined. Based on the research results for the highest density of tree vegetation found in plot 4 with the absolute density of 175 Ind/ ha this is in line with the highest litter productivity value also found at high density (plot 4) which is 14,5 gr/m2/week. Physical chemical factors are found in high density of air temperature 26 0C, humidity 80 %, soil temperature 25 0C, light intensity 118 Candella, soil pH 5.6, C-Organic 4.80 %, N-Total 0.55%, C/N of 4,24 %, P-Bray 23,03 ppm and K-tukar 0,41 Me/100.

Further Studies upon Chemical Factors Affecting the Breeding of Anopheles in Trinidad

1934 ◽  
Vol 25 (4) ◽  
pp. 491-494 ◽  
Author(s):  
P. A. Buxton
Keyword(s):  
Analytical Study ◽  
Chemical Constituents ◽  
Physical Factors ◽  
Factors Affecting ◽  
Early Stages ◽  
Freshwater Biology ◽  
Chemical Technique ◽  
Chemical Factors ◽  
Physical And Chemical

During the last decade, entomologists have made progress in understanding the environment in which certain insects live; in particular, we begin to understand the effect of certain physical and chemical factors, which make up a part of the environment. With this gain in knowledge, it is sometimes possible to forecast outbreaks of insects and of diseases conveyed by them, and one can sometimes say that a particular alteration of the environment will result in loss or gain. But so far as mosquitos are concerned, one must admit that though much work has been devoted to the analytical study of the water in which the early stages are passed, the results are disappointing. A consideration of the published work suggests several reasons for this. Investigation into the ecology of the mosquito has had a vogue, and much of it has been done by workers who were isolated and whose knowledge of chemical technique and freshwater biology was limited. Apart from that, the inherent difficulties are great, for the worker must hunt for the limiting chemical and physical factors among a host of others which are doubtless unimportant, and there are few clues to indicate which of the chemical constituents of the water affects the mosquito. The data are therefore voluminous and it is difficult to reduce them to order and present them so that they can be readily understood.

Menadione nicotinamide bisulphite as a source of vitamin K and niacin activities for the growing pig

2000 ◽  
Vol 71 (1) ◽  
pp. 111-117 ◽  
Author(s):  
M. Marchetti ◽  
M. Tassinari ◽  
S. Marchetti
Keyword(s):  
Vitamin K ◽  
Control Diet ◽  
Live Weight ◽  
Organic Salt ◽  
Free Form ◽  
Food Supplementation ◽  
Sodium Bisulphite ◽  
Chemical Factors ◽  
And Control ◽  
Physical And Chemical

AbstractWhen compared with other menadione derivatives such as menadione sodium bisulphite (MSB), menadione nicotinamide bisulphite (MNB), an organic salt combining menadione and nicotinamide, shows better stability towards physical and chemical factors once it is added to pre-mixes or foods. The present work evaluates the bioavailability of the two vitamins present in this compound and toxicity in the pig. To assess vitamin bioavailability, pigs were given small amounts of food containing MNB or equivalent amounts of MSB and nicotinamide in the free form. Menadione and nicotinamide concentrations in blood samples drawn at set times after the diets were given did not reveal any significant differences between the two modes of administration. Haematic levels of both vitamins in animals receiving MNB, or MSB and nicotinamide, were after 2, 4, 8 and 12 h higher (P < 0·001) than those of untreated animals. The tolerance level to MNB was evaluated in pigs given diets containing graded amounts of MNB (100, 500, 2500 mg/kg) for 28 days. No significant (P > 0·05) differences were recorded in live weight, food intake and gain/food ratio in pigs given these diets when compared with those given an unsupplemented diet. Haemoglobin and bilirubin levels did not differ between animals given various amounts of MNB and control animals. Plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in pigs given 100 mg/kg of MNB did not show significant differences when compared with those observed in pigs given an unsupplemented control diet. In pigs on the diets supplemented with 500 and 2500 mg/kg of MNB there was a significant increase in the two enzymatic activities as compared with controls (P < 0·001 and P < 0·01). In the case of ALT this had disappeared by 28 weeks. MNB is a good source of vitamin K for the pig and does not appear to have any adverse effects, even when administered at levels higher than those normally used in pig food supplementation.

The Qualitative and Quantitative Distribution of Plankton in the Strait of Georgia in Relation to Certain Oceanographic Factors

1957 ◽  
Vol 14 (4) ◽  
pp. 521-552 ◽  
Author(s):  
Joseph Eugène Henri Légaré
Keyword(s):  
Salinity Gradient ◽  
General Distribution ◽  
Fraser River ◽  
Strait Of Georgia ◽  
Quantitative Distribution ◽  
Qualitative And Quantitative ◽  
Chemical Factors ◽  
Physical And Chemical ◽  
Plankton Communities ◽  
Made In

In order to gain some picture of the seasonal variations in the plankton communities two cruises were made in the Strait of Georgia, one in June 1955, and the other in November 1955; 165 plankton collections were taken, also surface temperatures.The correlation of these data have resulted in a number of conclusions concerning the distribution of plankton in the Strait of Georgia. The chief factor affecting the general distribution of plankton is the salinity gradient. The inflow of fresh water from the Fraser River forms zones of varying properties, and leads to the development of different plankton communities. The extent to which physical and chemical factors may determine the presence or absence of certain organisms from the zones described is discussed.

scholarly journals Density and Flock Size of the Raven (Corvus corax) In the Orawa - Nowy Targ Basin During Non-Breeding Season

Ring ◽  
2006 ◽  
Vol 28 (2) ◽  
pp. 119-125
Author(s):  
Michał Ciach ◽  
Dominik Wikar ◽  
Małgorzata Bylicka
Keyword(s):  
Breeding Season ◽  
Early Spring ◽  
Food Resources ◽  
High Density ◽  
Line Transect ◽  
Flock Size ◽  
Early Winter ◽  
Corvus Corax ◽  
Line Transect Method ◽  
Breeding Seasons

Density and Flock Size of the Raven (Corvus corax) In the Orawa - Nowy Targ Basin During Non-Breeding Season During the 2002/2003-2004/2005 non-breeding seasons the density of the Raven in the open habitats of the Orawa - Nowy Targ Basin was studied by line transect method. The results were analysed in four periods (autumn, early winter, winter and early spring). The median density of Ravens did not differ significantly between individual periods and was respectively: 3.5, 3.8, 4.8 and 3.8 indiv. / 10 km. Number of birds during particular controls varied from 1.0 to 24.8 indiv. / 10 km. However, while excluding flocks, the median density of single individuals and pairs of the Raven was considerably lower and in subsequent periods reached respectively: 2.2, 2.4, 2.2 and 1.7 indiv. / 10 km. Flock size did not differ significantly between individual periods. Single individuals and, less often, groups of two birds were recorded mostly. Small (3-5 indiv.) and medium (6-15 indiv.) flocks were recorded rarely and large flocks (16 indiv. and above) - only exceptionally. The high density and strong fluctuations of abundance of Ravens were determined by flocks presence, which was probably linked to irregular occurrence of food resources.

scholarly journals The first report of ants (Formicidae: Hymenoptera) in salt marshes and salt pans in central parts of Iran

2019 ◽  
Vol 20 (9) ◽  
Author(s):  
MOHAMMAD REZA MOHSENI ◽  
SHAHROKH PASHAEI RAD
Keyword(s):  
Salt Marshes ◽  
Dominant Species ◽  
Salt Lake ◽  
Vegetation Density ◽  
Chemical Parameters ◽  
Salt Pans ◽  
Mountain Station ◽  
Physical And Chemical Parameters ◽  
Physical And Chemical ◽  
First Time

The present study was conducted in Salt marshes and Salt pans in central parts of Iran. 121 specimens of ants were collected by trapping and hand during spring, summer and autumn 2017 to 2019. Nine species belong to two subfamilies of Myrmicinae and Formicinae were identified. The vegetation, physical and chemical parameters of soil such as salinity, Ph, and other factors were investigated. Darband Shoor Mountain station with five species had the highest diversity and vegetation density and the lowest salinity of soil (72.14 ds/m) whereas Salt Lake station had only one species, with no vegetation and the highest salinity of soil (153.15 ds/m). Cataglyphis lividus (André, 1881) was the dominant species in all the stations except in Darband Shoor Mountain station. All the species were reported for the first time from salt marshes and salt pans in the central parts of Iran and were approved by Prof. Brian Taylor, in Royal Entomological Society of London, England.

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