Articles by Carl Johan Westman

A simple, manually-operated and easily portable device for sampling volumetric soil cores to a depth of 100 cm with a minimum soil disturbance is described. The device consists of a sample tube, a sampler and an extension tube. A dead blow nylon mallet is used to force the sampler into the soil and a small winch attached to an aluminium tube pulls the sampler from the soil. The total weight of the equipment (sampler, mallet and winch) is 18.5 kg and may be carried in the trunk of a small car. Sampling is easily done by one person in good physical condition but four-handed operation is recommended as more efficient. The sampling device has been in heavy use during the summers of 1993–95 when several hundred soil cores have been extracted on various sites all over Finland.

• Westman, E-mail: cw@mm.unknown

In soil profiles from a series of uplands of different site types bulk density, density of solids and porosity of soil were clearly related to soil organic matter content and its distribution in the soil profile. Soil organic matter contents were also strongly correlated to effective cation exchange capacity (CEC) and soil acidity. Site fertility was primarily related to the fine fraction (ø<0.06 mm) content in the C horizon and related properties (i.e. CEC). In the humus layer, the content of exchangeable bases and base saturation most strongly related to site fertility.

The PDF includes an abstract in English.

• Westman, E-mail: cw@mm.unknown

A method for calculation of the effect of practical fertilization for economic evaluation is presented and discussed. 55 Norway spruce (Picea abies (L.) H. Karst.) dominated stands on Oxalis-Myrtillus type sites were surveyed five to eight years after fertilization with nitrogen (90-170 kg/ha). The relationships between the fertilization effect and various stand characteristics were discussed. Fertilization increased the growth of the stands on an average by 2.2 m³/ha/year. In total the increase of tree growth during the research period was 17.5 m3/ha. This corresponds to a yield of 525–659 FIM/ha.

The PDF includes a summary in English.

• Westman, E-mail: cw@mm.unknown
• Leikola, E-mail: ml@mm.unknown
• Nummi, E-mail: tn@mm.unknown

Transects from upland to peatland sites were laid out so as to encounter a wide range of nutritional and hydrological conditions and volumetric soil samples were taken at 20 m intervals. For organic material, in particular peats, the correlation of ignition loss with CEC and total N were clearly higher when the variables were expressed volumetrically. The volumetric expression of variables made comparison of soils with varying organic matter contents possible. In preliminary analyses of the relationships between soil variables and dominant height of the tree stand on mineral soil sites volumetric exchangeable bases, pH and C/N -ratio in the raw humus layer showed a significant correlation.

The PDF includes a summary in Finnish.

• Westman, E-mail: cw@mm.unknown
• Laine, E-mail: jl@mm.unknown
• Starr, E-mail: ms@mm.unknown

Application of nitrogen at levels of 200, 400 and 600 kg ha^-1 resulted in increases of 35, 18 and 12% in the photosynthetic rate in young Scots pine (Pinus sylvestris L.). The number of buds, degree of branching, and needle size were positively related to the amount of nitrogen applied. A 10–40% increase in the average needle area was found. A positive correlation was found between total photosynthesis and stem growth.

The PDF includes a summary in Finnish.

• Kellomäki, E-mail: sk@mm.unknown
• Puttonen, E-mail: pp@mm.unknown
• Tamminen, E-mail: ht@mm.unknown
• Westman, E-mail: cw@mm.unknown

The paper deals with the nutrient status of surface peat layer from virgin sedge-pine swamps and its relationship to peatland types. When the nutrients are expressed in mg/100 g peat, only easily extractable Ca and Mg correspond to the productivity status of the peatland type. N, P, and K levels in the herb rich sedge-pine swamp are generally lower than in the small sedge-pine swamps, which are the least productive ones. The differences between the site types in all the five nutrients become much clearer when the results are expressed in kg/ha. P, K, and Ca are significantly different between the site types, and correspond to the productivity of the site type. For N and Mg the same tendency can be seen. The organically bound nutrients N, and to a lesser extent, P appear to comply with the hypothesis of an increase in nutrient availability in Southern Finland.

The PDF includes a summary in Finnish.

• Starr, E-mail: ms@mm.unknown
• Westman, E-mail: cw@mm.unknown

The paper describes an attempt to determine whether ammonium, nitrate and urea nitrogen are bound in peat used as a filling material in containerized seedling production, what is the effect of the nutrients on certain chemical properties in the peat, and what is the effect of the nitrogen fertilizers on the primary growth of containerized (paper-pot VH 608) Scots pine (Pinus sylvestris L.) seedlings in connection with planting out. The seedlings were fertilized with ammonium sulphate, potassium nitrate and urea.

The results show that none of the fertilizers used were bound in the peat. The nitrogen content in the above ground part of the seedlings increased clearly. Fertilization with ammonium sulphate resulted in the greatest increment and this increase appears to be permanent. The wintering process was somewhat delayed by the fertilization. The seedling mortality rate for all the treatments has been quite appreciable. However, fertilization particularly with ammonium sulphate on the poorer of the two sites studied has had a positive effect on seedling survival. Furthermore, it appears that fertilizer treatments have decreased growth after planting, but in the case of ammonium sulphate this decrease has changed into a clear growth increment.

The PDF includes a summary in English.

• Westman, E-mail: cw@mm.unknown

This study forms part of a project designed to elucidate the total nutrient budget of a Scots pine (Pinus sylvestris L.) stand in Central Finland during the 1974 growing period. Precipitation has been divided up into precipitation, throughfall and stemflow.

The acidity of the rainwater was found to increase in the order – Precipitation, throughfall and stemflow. The electrolyte content of the rain water from throughfall and stemflow was higher than that of precipitation. The nutrient contents of precipitation were rather low. Throughfall and stemflow were found to leach some nutrient from the trees. This was most clear in the case of potassium. The total amounts of nutrients reaching the ground in throughfall were found to be smaller than those in precipitation. On the other hand, the amounts of potassium, calcium and magnesium in stemflow were clearly greater than those in precipitation.

The PDF includes a summary in English.

• Lehtonen, E-mail: il@mm.unknown
• Kellomäki, E-mail: sk@mm.unknown
• Westman, E-mail: cw@mm.unknown

The paper describes a preliminary attempt to assess the long-term effect of urea application on the quantity of nitrogen available for plants in forest soil. The soil samples required for the study were collected from an experimental area which had been set up for investigations into both the single and joint effect on tree growth of two levels of each of urea and phosphorus application. The stand was a mixed forest of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) H. Karst.) on Myrtillus type site with an average volume of 217.5 m³/ha.

According to the results, the nitrogen available for plants of the humus layer was significantly higher in fertilized than in unfertilized plots as late as four years after application. In terms of absolute values, the quantities were extremely small, only 3–4% of the amounts applied. In comparison with these results it was interesting to notice that urea application seemed to increase the C/N ratio.

The PDF includes a summary in English.

• Westman, E-mail: cw@mm.unknown

Multivariate methods are used to classify pine mires on the basis of edaphic properties into fertility groups in order to estimate the effect of fertilization in relation to site fertility. The data is based on two field inventories of NPK fertilization experiment in which 2,624 sample trees on 164 sample plots from 19 experimental fields were measured on Scots pine (Pinus sylvestris L.) dominated stands. The edaphic properties (total contents of nutrients and related properties) are based on 1,350 volumetric sub-samples of fertilized and non-fertilized control plots.

In a DECORANA ordination, based on standardised volumetric soil variables N-P and acid-base gradients jointly describing trophic status were distinguished. Mainly on the basis of these two gradients a TWINSPAN analysis divided the material into five edaphic groups. To independently allocate sample plots into fertility groups, discriminating multiple regressions were formed using the TS edaphic groups as class variable.

The effect of N, P, K, NP, NK, PK, and NPK treatments on tree growth was estimated on the basis of change in relative basal area increment during two growth periods. During five-year period immediately after fertilization N and P treatments evoked the strongest increase in growth. On the nutrient poor sites, the effect was almost double that on the fertile sites. The effect of N was short lasting while the P treatment still affected growth after 5–11 years. Although K treatment had little influence on tree growth needle samples collected 11 years after fertilization indicated increased K uptake on fertilized plots.

Generally, the effect of fertilization on absolute stand volume growth was small. During the 11-year study period the total increase in growth gained with NPK was some 3–4 m³/ha. Despite strong relative response of individual sample trees, due to low stand volume fertilization (and drainage) had practically no effect on volume growth on the sites of lowest fertility.

The PDF includes a summary in Finnish.

• Westman, E-mail: cw@mm.unknown

The aims of the present study were to determine physical and physio-chemical properties of some Finnish forest tree nursery soils, and to examine relationships between these properties and the amount of organic matter in the soil.

The following soil tillage layer properties of 33 fields belonging to 8 forest tree nurseries were determined: soil particle size distribution, organic matter content, bulk density and density of solids, total pore space, soil water volume at potentials pF 2.0 and 4.2, available water content and air space at potential pF 2.0, active acidity, electrical conductivity index and cation exchange capacities at pH 4.5 and 8.0. The soil texture class of the tillage layer parent material was sand, only in a few cases did higher percentage of silt and clay indicate a morainic nature of parent material. The amount of organic material in the soils varied within wide limits, reflecting differences in amelioration policy between the single nurseries.

Relationships between the physical properties of the soil parent material and those related to fertility were in most cases strongly influenced by the amount of soil organic matter. Soil density values decreased as the organic matter content increased from 2 to 25%, giving rise to the increase in the total pore space. However, the amount of water held at potential pF 2.0 and the available water content did not increase with increasing organic matter content. This was due to the absence of the particle fraction in the sand. Nursery soil amelioration, involving in most cases a mixture of Sphagnum peat with sand, thus gives rise to an increase in the content of drainable water.

Cation exchange capacities were positively correlated with the organic matter content. However, the absolute number of exchange sites expressed as equivalents in the tillage layer did not increase in accordance with the increase in organic matter content due to the influence of the organic matter content upon the ratio of solids in the voids.

The PDF includes a summary in English.

• Westman, E-mail: cw@mm.unknown

Fertility of surface peat from sedge pine mires was studied by measuring several edaphic growth factors: bulk density, volume weight of organic matter, ash content, acidity, electric conductivity, effective cation exchange capacity, degree of base saturation, and total contents of N, P, K, Ca and Mg. The 168 temporal sample plots were situated on virgin sedge mires in different parts of Finland, and the 30 permanent sample plots on two uniform sedge mires.

The results showed that peat bulk density and volume weight of organic matter tend to increase with increasing site quality. Ash content increased gradually in the site series from small sedge mire to the herb-rich sedge mire. The relationship between the total content of macronutrients in peat and the site quality is clear. The importance of bulk density in evaluating the site quality is further emphasized when taking into account its significant correlation to contents of N and P. The soil variables follow the accepted quality gradient of the site series. Consequently, the plant sociologically based site classification seems to reflect satisfactorily the average soil properties. However, the within site variation was significant.

• Westman, E-mail: cw@mm.unknown

• Levula, University of Helsinki, Department of Forest Ecology, FIN-00014 University of Helsinki, Finland E-mail: janne.levula@helsinki.fi
• Ilvesniemi, University of Helsinki, Department of Forest Ecology, FIN-00014 University of Helsinki, Finland E-mail: hi@nn.fi
• Westman, University of Helsinki, Department of Forest Ecology, FIN-00014 University of Helsinki, Finland E-mail: cjw@nn.fi

• Chantal, University of Helsinki, Dept. of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: michelle.dechantal@helsinki.fi
• Eskola, University of Helsinki, Dept. of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: le@nn.fi
• Ilvesniemi, University of Helsinki, Dept. of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: hi@nn.fi
• Leinonen, University of Helsinki, Dept. of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: kl@nn.fi
• Westman, University of Helsinki, Dept. of Forest Ecology, P.O. Box 27, FIN-00014 University of Helsinki, Finland E-mail: cjw@nn.fi