Xylem sap analysis for determining nutritional status of trees: Pseudotsugamenziesii

1985 ◽  
Vol 15 (2) ◽  
pp. 429-437 ◽  
Author(s):  
N. Stark ◽  
C. Spitzner ◽  
D. Essig
Keyword(s):  
Xylem Sap ◽  
Time Of Day ◽  
Tree Age ◽  
Poor Growth ◽  
Field Problem ◽  
Soil Extracts ◽  
Growth Site ◽  
Ion Concentrations ◽  
The Poor ◽  
Time Of Year

Xylem sap extraction of branches as a new field problem-solving technique in forestry, environmental pollution, and botany is described. The influence of extraction pressure, crown aspect, height into the crown, tree age, time of year and day, and soil chemistry on the ion concentrations in xylem sap are discussed. Xylem sap extraction with a pressure chamber provides a good indication of the nutrient status of a species if the trees are of similar age, and if they are sampled at the same aspect, crown height, time of day, time of year, and on the same soils. Pseudotsugamenziesii (Mirb.) Franco (Douglas-fir), growing on nutrient-poor acid soils and moderately fertile alkaline soils showed significant differences in growth rate and ion concentrations in the xylem sap and soil. Trees on the faster growth site (< 12 rings/2.54 cm) had significantly more Ca, K, Mn, P, and N in the xylem sap. Trees on the poor growth site had high levels of Mg in the sap. Trees growing on the poor site which was also K deficient transpired more rapidly than those with faster growth. It is hypothesized that insufficient plant K could reduce the ability of the guard cells to control water loss. The stem water potential was slightly, but not significantly, higher on the poor growth site. Although there is no proof that the deficient ions are the cause of poor growth, they are suspect, given the similar water availability on the two sites. The concept of nutrient supplying potential of a tree, or its ability to supply its needles and meristems with water and nutrients is discussed. Distilled water soil extracts and foliar analyses would not have reflected the same ion relationships (deficiencies or excesses) that are evident in the xylem sap. Evidence for the factors controlling growth in these stands is being sought through fertilizer tests.

Xylem sap analysis for determining the nutrient status and growth of Pinusponderosa

1985 ◽  
Vol 15 (5) ◽  
pp. 783-790 ◽  
Author(s):  
N. Stark ◽  
C. Spitzner
Keyword(s):  
Ponderosa Pine ◽  
Soil Chemistry ◽  
Natural Variation ◽  
Xylem Sap ◽  
Tree Height ◽  
Nutrient Status ◽  
Time Of Day ◽  
Ion Concentration ◽  
Ion Concentrations ◽  
Energy Stress

Natural variation in the ion concentration of the xylem sap of ponderosa pine (Pinusponderosa Laws.) in Montana was studied relative to tree height, crown aspect, age, time of day and year, species, tree to tree (within-stand variation), soil chemistry, and growth prediction. Xylem sap was extracted from branches at 2.4–2.7 MPa. The sap was analyzed chemically for 13 ions and total nitrogen. Extraction and analysis are fast and inexpensive. The top third of the crowns of P. ponderosa normally had higher ion concentrations in the sap for all but four ions. Crown aspect has little effect on the ion concentrations in sap. Age is a significant factor in xylem sap ion concentrations. Trees to be compared should be within 10 years in age. Time of day causes significant changes in ion concentration in the sap, but two stands can be compared over the same 2 to 8 sunlight hours. Xylem sap can be collected easily in the winter from frozen branches or in the summer when transpiration should be measured as well. Most ions decrease in concentration in the sap from the time of flush through hardening off. Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) sap has higher Ca than P. ponderosa sap. Slowly growing P. ponderosa had low Ca, Mn, K, P, and N, but high Mg and Si in the sap, compared with more rapidly growing trees. Xylem sap shows promise as a means of simultaneously evaluating the water, nutrient, and energy stress of trees and may be useful as a rapid means of predicting various parameters of tree growth.

scholarly journals Key soil parameters affecting the survival of Panax notoginseng under continuous cropping

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Wumei Xu ◽  
Fengyun Wu ◽  
Haoji Wang ◽  
Linyan Zhao ◽  
Xue Liu ◽  
...  
Keyword(s):  
Soil Ph ◽  
Pearson Correlation ◽  
Principal Component ◽  
Panax Notoginseng ◽  
Soil Parameters ◽  
Continuous Cropping ◽  
Poor Growth ◽  
Available N ◽  
The Poor ◽  
Replant Problem

AbstractNegative plant-soil feedbacks lead to the poor growth of Panax notoginseng (Sanqi), a well-known herb in Asia and has been used worldwide, under continuous cropping. However, the key soil parameters causing the replant problem are still unclear. Here we conducted a field experiment after 5-year continuous cropping. Sanqi seedlings were cultivated in 7 plots (1.5 m × 2 m), which were randomly assigned along a survival gradient. In total, 13 important soil parameters were measured to understand their relationship with Sanqi’s survival. Pearson correlation analysis showed that 6 soil parameters, including phosphatase, urease, cellulase, bacteria/fungi ratio, available N, and pH, were all correlated with Sanqi’s survival rate (P < 0.05). Principal component analysis (PCA) indicated that they explained 61% of the variances based on the first component, with soil pH being closely correlated with other parameters affecting Sanqi’s survival. The optimum pH for Sanqi growth is about 6.5, but the mean soil pH in the study area is 5.27 (4.86–5.68), therefore it is possible to ameliorate the poor growth of Sanqi by increasing soil pH. This study may also help to reduce the replant problem of other crops under continuous cropping since it is widespread in agricultural production.

Effect of time of day, time of year, and life history strategy on time budgeting in juvenile Atlantic salmon, Salmo salar

1999 ◽  
Vol 56 (12) ◽  
pp. 2397-2403 ◽  
Author(s):  
Sveinn K Valdimarsson ◽  
Neil B Metcalfe
Keyword(s):  
Life History ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Life History Strategy ◽  
Time Of Day ◽  
Life History Strategies ◽  
Foraging Efficiency ◽  
Atlantic Salmon Salmo Salar ◽  
Juvenile Atlantic Salmon ◽  
Time Of Year

Traditionally, behavioural studies on juvenile Atlantic salmon, Salmo salar, have been conducted during the day in summer. It is known that Atlantic salmon become nocturnal in winter, but very little is known about their behaviour at that time. Therefore, observations in a seminatural stream were carried out during the day and night, from February to June, comparing diel and seasonal differences in behaviour between fish adopting alternative life history strategies. The results showed a general trend for more activity in spring than in winter, and the fish were found to be foraging at surprisingly low light levels. There were differences in relative feeding rate between the life history strategies; the early migrant fish foraged mostly during the day whereas the delayed migrant fish did more foraging at night. There is some evidence that the early migrant fish made fewer feeding attempts over the winter, which is surprising, since they grow faster over that period. This suggests differences in foraging efficiency, which could contribute to the separation into these two life history strategies.

scholarly journals Potato Importance for Development Focusing on Prices

2021 ◽  
Vol 14 (3) ◽  
pp. 137
Author(s):  
Olli Salmensuu
Keyword(s):  
Developing Countries ◽  
Economic Effects ◽  
Social Significance ◽  
Poor Growth ◽  
The Poor ◽  
Potato Price ◽  
General Welfare ◽  
Advanced Economies ◽  
Inferior Good ◽  
Developed World

This paper studies potato prices and consumption in the progress of economic development. Potato status tends to evolve from a luxury to a normal and, lastly, to an inferior good. In the developed world, where the potato thrived and became a food for the poor, prices of the inferior potato attract little interest due to general welfare, which further complicates discerning economic effects by computation. Contrarily, in many developing countries, due to supply constraints the potato is a relative expensive, non-staple, normal good, with little social significance. Whereas it is a common misconception that tastes in developing countries differ from advanced economies, low incomes, together with relatively high potato prices, present a real and obvious hindrance to wider potato use among the poor in the underdeveloped world. Local regressions on FAO data reveal empirical advantages favoring potato price system research in developing countries, more likely yielding predictable, statistically significant, unbiased results. Correct policies could increase potato importance in developing countries and stimulate sustainable and pro-poor growth where consumers receive affordable potatoes, while also producer incentives for greater productivity improve. Furthermore, potato-led research presents widening potential into also understanding general social structures of underdevelopment as similar factors explain both cross-border incomes and potato prices.

scholarly journals Pro-poor Growth: Concepts and Measurement with Country Case Studies (Distinguished Lecture)

2003 ◽  
Vol 42 (4I) ◽  
pp. 417-444 ◽  
Author(s):  
Nanak Kakwani ◽  
Hyun H. Son
Keyword(s):  
Economic Growth ◽  
Growth Rate ◽  
Poverty Reduction ◽  
Poor Growth ◽  
The Poor ◽  
Actual Growth Rate ◽  
Actual Growth ◽  
The Republic ◽  
Increasing Function ◽  
Proportional Reduction

This paper looks into the interrelation between economic growth, inequality, and poverty. Using the notion of pro-poor growth, we examine the extent to which the poor benefit from economic growth. First, various approaches to defining and measuring propoor growth are scrutinised using a variety of criteria. It is argued that the satisfaction of a monotonicity axiom is a key criterion for measuring pro-poor growth. The monotonicity axiom sets out a condition that the proportional reduction in poverty is a monotonically increasing function of the pro-poor growth measure. The paper proposes a pro-poor growth measure that satisfies the monotonicity criterion. This measure is called a ‘poverty equivalent growth rate’, which takes into account both the magnitude of growth and how the benefits of growth are distributed to the poor and the non-poor. As the new measure satisfies the criterion of monotonicity, it is indicative that to achieve rapid poverty reduction, the poverty equivalent growth rate—rather than the actual growth rate—ought to be maximised. The methodology developed in the paper is then applied to three Asian countries, namely, the Republic of Korea, Thailand, and Vietnam.

Pro-Poor Development through Tourism in Economically Backward Tribal Region of Odisha, India

2014 ◽  
pp. 983-994
Author(s):  
Soumendra Nath Biswas
Keyword(s):  
Social Institutions ◽  
Tribal Community ◽  
Skilled Workers ◽  
Poverty Eradication ◽  
Planning Commission ◽  
Poor Growth ◽  
Tribal Communities ◽  
Economic Progress ◽  
The Poor ◽  
Tribal Region

In India, tourism plays an important role in economic development and creation of jobs. The Approach Paper of the 12th Five Year Plan prepared by the Planning Commission highlights the need to adopt “pro-poor tourism” for increasing net benefits to the poor and ensuring that tourism growth contributes to poverty eradication. Tourism plays a key role in socio-economic progress through creation of jobs, enterprise, infrastructure, and revenue earnings. The Planning Commission has identified tourism as the second largest sector in the country in providing employment opportunities for low-skilled workers. Odisha has a large tribal population: out of India's 427 Scheduled Tribes, Odisha accounts for 62 tribal communities who constitute 27.08 percent of the state's population (2001). Of the 62 Scheduled Tribes, the state has declared 11 tribal communities as Primitive Tribal Groups. Each of these tribal communities is rich in social institutions and poor in economy. Achieving poverty eradication requires actions on a variety of complementary fronts and scales, but a prerequisite of significant progress is pro-poor growth – growth that benefits the poor tribal community. This chapter explores these.

STUDIES ON BROWNING ROOT ROT OF CEREALS: VI. FURTHER CONTRIBUTIONS ON THE EFFECTS OF VARIOUS SOIL AMENDMENTS ON THE INCIDENCE OF THE DISEASE IN WHEAT

1940 ◽  
Vol 18c (6) ◽  
pp. 240-257 ◽  
Author(s):  
T. C. Vanterpool
Keyword(s):  
Root Rot ◽  
Nutrient Deficiencies ◽  
Sweet Clover ◽  
Poor Growth ◽  
Prairie Soils ◽  
Pythium Root Rot ◽  
The Poor ◽  
Copper Manganese ◽  
Supplemental Nutrients ◽  
Severe Leaf

Further work has substantiated earlier findings that phosphatic fertilizers and farm manure will give adequate control of Pythium root rot of wheat in infested prairie soils. The improvement in growth resulting from these amendments is considered to be due to the production of a larger number of quicker growing roots which lessens the chances for infection and leaves more roots healthy, though the same percentage may be affected as in diseased plants showing severe leaf discolorations. Experiments have failed to indicate that the phosphatic materials increase resistance appreciably. Nitrogenous materials when applied singly had virtually no effect on growth, but once ample phosphorus was added, further nitrogen applications gave substantially greater increases than phosphate alone. Phosphorus is apparently the chief limiting element. No difference was found in preliminary tests in the phosphate-fixing power of browning and normal soils. Typical browning soils responded irregularly to small applications of boron, copper, manganese, or zinc, but were not found to be seriously lacking in these elements. Moderate benefits resulted from heavy applications of gypsum and of sulphur. Browning soil was found also to be deficient in phosphate for non-cereals such as alfalfa, buckwheat, carrots, flax, lettuce, and sweet clover. These crops were not attacked by the Pythium spp. pathogenic to cereals. Consequently the poor growth of the non-cereals in browning soil appears to be due to nutrient deficiencies, while the poor growth of cereals is due to both root-destroying fungi and nutrient deficiencies. In both instances phosphorus is probably the chief limiting element. Ground cereal straw, sweet clover hay, and weed hay amendments gave moderate increases m the growth of wheat. No consistent differences were found in the carbon-nitrogen ratios of browning and normal soils. The results as a whole suggest that two of the most practicable means of meeting the browning root-rot situation are, firstly, to supply supplemental nutrients in the form of artificial fertilizers, and secondly, to add organic residues or farm manure regularly to fields subject to the disease.

Induction of Cryptococcus laurentii α-galactosidase

2012 ◽  
Vol 66 (9) ◽  
Author(s):  
Csilla Mészárosová ◽  
Nadežda Kolarova ◽  
Renáta Vadkertiová ◽  
Eva Stratilová
Keyword(s):  
Carbon Source ◽  
Surface Activity ◽  
Membrane Fraction ◽  
Cryptococcus Laurentii ◽  
Direct Influence ◽  
Galactose Metabolism ◽  
Cultivation Medium ◽  
Poor Growth ◽  
The Poor

AbstractThe surface activity of Cryptococcus laurentii α-galactosidase can be significantly (up to 80 times) influenced by a carbon source present in a cultivation medium. Induction of this enzyme is stimulated by the presence of saccharides containing bound galactose. The highest activity observed when the cells grew in a lactose medium was probably a consequence of the absence of cleavage products serving as repressors (glucose). This idea is supported by the poor growth of cells in the medium with lactose as the carbon source. The induction of surface α-galactosidase was accompanied by increased activities in cytosole. The membrane fraction also contained this enzyme, but the influence of the carbon source was not proportional. The induction of α-galactosidase may play an important role in galactose metabolism of the genus Cryptococcus with a direct influence on the virulence of these capsular yeasts.

Analysis of an Instaneous Census Method for Heathland Birds

1983 ◽  
Vol 10 (3) ◽  
pp. 521 ◽  
Author(s):  
GH Pyke
Keyword(s):  
Frequency Distribution ◽  
Bird Species ◽  
Time Of Day ◽  
Vegetation Height ◽  
Time Of Year

Birds were censused from the top of a 2.5-m ladder positioned at the centre of circles of radius 20 m. Every 1 min the observer visually scanned one half of a circle, recording the identity of and the distance to every bird seen. This procedure was carried out for about eight scans and then repeated for the complementary semicircle. Birds tended to be repulsed from the observer and/or ladder. Consequently the census method cannot be used to estimate absolute densities. However, the frequency distribution of bird-observer distances was found to be independent of time of day, time of year, and bird species. The method can, therefore, be used at a particular location to compare different bird species and different times. Vegetation height affected the frequency distribution of bird-observer distances and so the method cannot provide accurate comparisons of bird densities in different areas. Fewer birds were seen per scan when the census was carried out 4-6 h after sunrise. The two observers in the study saw the same average number of birds per scan.

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