Forest humus type governs heavy metal accumulation in specific organic matter fractions

Soils have the potential to accumulate heavy metals and the capacity to do so is strongly related the properties of each soil. Soil organic matter is a key factor in the retention, release, and bioavailability of heavy metals, and here we have determined the accumulation of heavy metals in various types of humus in the Rybnik Forest District in southern Poland. In a novel approach, we analyzed relationships between heavy metals within soil organic matter fractions and evaluated the role of organic fractions in mediating metal mobility. Specifically, we tested whether (i) the type of forest humus determines the heavy metal accumulation; (ii) heavy metals accumulation is associated with soil organic matter fractions; and (iii) heavy metals have an inhibitory influence on biochemical properties especially enzymes activity in different humus types. Four types of humus were sampled (mor, moder, moder-mull, mull), physically fractioned, and a number of chemical and biochemical properties were analyzed. Calculated geo-accumulation index (Igeo) and enrichment factor (EF) confirmed soil pollution with Cd and Pb. The type of humus differed in the accumulation of heavy metals, which is associated to the variable concentration of organic matter remaining at each decay class. We found no relationship between enzymatic activity and heavy metals concentration except for a positive correlation between urease activity and nickel concentration. Considering wider evidence, we propose a biogeochemical link between nickel deposition and the production of soil-borne urease in these forest soils

Influence of man-made edaphotopes of the spoil heap on biota

The aim of the work is to investigate the influence of man- made edaphotopes of colliery spoil heap on biota by bioindication method. The physicochemical properties of edaphotopes were investigated: humidity, substrate temperature, humus content at different intervals of their depth and on different sections of the waste heap. The storage technologies of mineral waste in the dumps disregard its further use and transforming that occurs over time. It was revealed that on the northern slope exposures the greatest amount of moisture was concentrated and temperature regimes were acceptable for the activity of the soil biota, which was proved by the largest amount of biomass. New dependences of humus content in edaphotopes of the heap in different intervals of their depth from biomass of humus-forming organisms were established. Slight successional processes on the surface of the heap were observed, where young flora began to develop. This positive phenomenon will contribute to the humus of the genetic horizons and the development of tree and shrub vegetation. Favourable conditions for the development of neo-terrain and the formation of a new landscape in mining regions were confirmed

Effect of humus supplement on growth, digestibility and nutritional efficiency of juvenile Helix aspersa snail

El humus es importante en la dieta de Helix aspersa y de otras especies de caracoles comestibles aunque su contribución nutricional es poco conocida. En el presente trabajo se evalúa el efecto de un suplemento con humus sobre el crecimiento, eficiencia nutricional y digestibilidad del caracol H. aspersa durante la fase juvenil. El experimento se hizo en laboratorio usando un diseño completamente al azar con dos tratamientos (dietas) con diez repeticiones de veinte caracoles: dieta I, concentrado comercial para gallinas ponedoras; dieta II, concentrado comercial para gallinas ponedoras más un suplemento con humus comercial de lombriz. Cuando los caracoles juveniles H. aspersa crecen en presencia de humus lo consumen regularmente y aumentan la velocidad de crecimiento (478.71±8.26 mg sin humus, dieta I; 912.21±9.42 mg con humus, dieta II; p≤0.01). El humus también aumenta la disponibilidad de los nutrientes orgánicos de la dieta, mejorando la digestibilidad de la materia seca (54.21±2.12% sin humus, dieta I; 80.13±1.37% con humus, dieta II; p≤0.001), energía bruta (56.32±3.13% sin humus, dieta I; 65.56±4.21% con humus, dieta II; p≤0.001), proteína cruda (63.14±3.41% sin humus, dieta I; 74.56±2.82% con humus; dieta II; p≤0.01), fibra detergente neutro (56.68±4.84% sin humus, dieta I; 66.64±3.21% con humus, dieta II; p≤0.01) y fibra detergente ácido (35.32±3.32% sin humus, dieta I; 47.42±2.13% con humus, dieta II; p≤0.001). Por tanto, se mejoró la razón de conversión alimenticia (1.12±0.14 sin humus, dieta I; 0.78±0.11 con humus, dieta II; p≤0.01) y la razón de eficiencia proteica (6.40±0.09 sin humus, dieta I; 11.09±0.15 con humus, dieta II; p≤0.01).Humus is important in the diet of Helix aspersa and other species of edible snails although its nutritional contribution is not well known. In this study the effect of a humus supplement on the growth, nutritional efficiency and digestibility of the snail H. aspersa in its juvenile stage was evaluated. The experiment was done under laboratory conditions using a completely randomized design with two treatments (diets) with ten replications of 20 snails: Diet I, commercial concentrate for laying hens; Diet II, the same commercial concentrate plus a commercial humus supplement for earthworms. When H. aspersa juvenile snails grow in the presence of humus, they feed regularly on the supplement and grow significantly faster (478.71±8.26 mg without humus, diet I; 912.21±9.42 mg with humus, diet II; p≤0.01). Humus also increases the availability of the diet’s organic nutrients, improving digestibility of dry matter (54.21±2.12% without humus, diet I; 80.13±1.37% with humus, diet II; p≤0.001), raw energy (56.32±3.13% without humus, diet I; 65.56±4.21% with humus, diet II; p≤0.001), crude protein (63.14±3.41% without humus, diet I; 74.56±2.82% with humus; diet II; p≤0.01), neutral detergent fiber (56.68±4.84% without humus, diet I; 66.64±3.21% with humus, diet II; p≤0.01) and acidic detergent fiber (35.32±3.32% without humus, diet I; 47.42±2.13% with humus, diet II; p≤0.001). Therefore, the feed conversion ratio was improved (1.12±0.14 without humus, diet I; 0.78±0.11 with humus, diet II; p≤0.01) and the protein efficiency ratio (6.40±0.09 without humus, diet I; 11.09±0.15 with humus, diet II; p≤0.01)

Ergebnisse der Anwendung einer neuen Humusbilanzmethode in Dauerfeldversuchen

Humus balance methods aim at the assessment of humus reproduction in cropping systems as an effect of cropped plant species and management. They do not intend to predict actual humus dynamics, which are strongly dependent on land-use history and environmental site conditions. Therefore, the validation of humus balance methods is a methodical challenge. This paper presents results from the validation of a new method for humus balancing with different approaches. The first validation approach is relating humus balance saldi to humus content development in long-term field experiments. The second approach is relating humus balance saldi differences between field experiment treatments under similar site conditions to differences in humus dynamics indicators. In both validations the model performed satisfactory. Compared to standard humus balance methods applied in organic farming, the new method proved comparable quality in the validation. However, there is a clear demand for methodical improvement of validation approaches for humus balance methods

Organic substrates in the development of camu-camuzeiro (Myrciaria dubia (H. B. K.) McVaugh) in the amazon region

Amazon is the largest tropical forest on the planet, it has a variety of plant species with emphasis on manyfruit trees, such as the camu-camuzeiro (Myrciaria dubia (H. B. K.) McVaugh), which occurs naturally on thebanks of rivers, lakes, lowlands and flooded forest of the Amazon. The objective of this study is to evaluate thedevelopment of camu-camuzeiro seedlings in different organic substrates. The experiment was conductedin the seedling production nursery of the Federal Rural University of Amazon. The experimental design wasentirely randomized, with ten treatments and five repetitions, each portion was represented by ten plants,totaling 500 seedlings. The substrates evaluated were: T1 - Humus; T2 - Humus + Bird manure; T3 - Humus + Bovinemanure; T4 - Humus + Açaí kernel; T5 - Humus + Chestnut shell; T6 - Humus + Chestnut shell + Poultry manure;T7 - Humus + Bovine manure + Chestnut shell; T8 - Humus + Açaí kernel + Poultry manure; T9 - Humus + Açaíkernel + Bovine manure; T10 - Commercial. The different substrates used influenced the development of camucamuzeiroseedlings evaluated at 180 days. The treatments with a substrate based on Humus (T1), Humus + Açaíkernel (T4), Humus + Chestnut shell (T5), Humus + Chestnut shell + Poultry manure (T6), Humus + Bovine manure +Chestnut shell (T7), Humus + Açaí Kernel + Bovine manure (T9) and the commercial substrate (T10) are the bestfor a satisfactory development of this crop in the production field.Amazon is the largest tropical forest on the planet, it has a variety of plant species with emphasis on manyfruit trees, such as the camu-camuzeiro (Myrciaria dubia (H. B. K.) McVaugh), which occurs naturally on thebanks of rivers, lakes, lowlands and flooded forest of the Amazon. The objective of this study is to evaluate thedevelopment of camu-camuzeiro seedlings in different organic substrates. The experiment was conductedin the seedling production nursery of the Federal Rural University of Amazon. The experimental design wasentirely randomized, with ten treatments and five repetitions, each portion was represented by ten plants,totaling 500 seedlings. The substrates evaluated were: T1 - Humus; T2 - Humus + Bird manure; T3 - Humus + Bovinemanure; T4 - Humus + Açaí kernel; T5 - Humus + Chestnut shell; T6 - Humus + Chestnut shell + Poultry manure;T7 - Humus + Bovine manure + Chestnut shell; T8 - Humus + Açaí kernel + Poultry manure; T9 - Humus + Açaíkernel + Bovine manure; T10 - Commercial. The different substrates used influenced the development of camucamuzeiroseedlings evaluated at 180 days. The treatments with a substrate based on Humus (T1), Humus + Açaíkernel (T4), Humus + Chestnut shell (T5), Humus + Chestnut shell + Poultry manure (T6), Humus + Bovine manure +Chestnut shell (T7), Humus + Açaí Kernel + Bovine manure (T9) and the commercial substrate (T10) are the bestfor a satisfactory development of this crop in the production field

Site adjusted organic matter balance method for use in arable farming systems

Common humus balance methods give distinct inexact results and do not meet nowadays requirements in Germany. Outgoing from the method of KOERSCHENS et al. (2004) an improved, site adjusted, semi-quantitative method was developed for manual use in agricultural practice and consultation. In the validation and optimization process over 300 variants from 39 long-term field trials were used, which represent the most important site conditions of Central Europe (Germany). The optimization work was done in four steps. Identification of site specific groups with homogenous humification levels. Distinct different humification characteristics were recognized for the organic matter of different German site conditions (soil, climate). Six site specific groups could be identified when comparing the results of the humus balancing with the field trial organic matter content changes of the soils. Humification coefficients of the crop species. The effects of the crop species cultivation, and the climate and soil conditions on the humification process were combined and expressed in the crop species humification coefficients. Optimal values were obtained when the results of the humus balancing were in accordance with the organic matter content chance of the trials (objective function: 0 kg Corg ha-1 ≈ 0 % Corg content change). Equal assessments of the site specific groups were reached by systematic adjustments of the humification coefficients of the crop species until the objective function was observed. Humification coefficients of the organic materials. Additional analyses of multiple long-term field trial results have shown, that the organic material coefficients of the common balance method were fixed at somewhat too high values. Over this, the humification values were negatively related to increasing supply of organic materials. Therefore, these coefficients were corrected according to the field trial results. Classification system for the humus balance results. The nitrogen surface balance of the field trials was suitable for to evaluate the soil fertility and environmental tolerance of the humus balance results. Under a specific N surplus constraint (e.g. 50 kg N ha-1), arable cultivation systems without mineral nitrogen fertilization (e.g. organic farming) can tolerate much higher humus surplus values than systems with increasing nitrogen fertilization. For use in different arable farming systems, therefore, the common classification scheme (A to E system of VDLUFA) was corrected. Through installation of humification coefficients in site-specific groups adjusted to the Corg content change in the soil, and adaptation of the humification coefficients of the organic materials, the optimization process resulted in a large improvement of the method accuracy (s2=0,034 to s2=0,011). For practical use, only a little information about site specific characteristics, the crop species in the crop rotation and the amounts of added organic materials are necessary in the calculations

Modelling Carbon Cycles as Basis of an Emission Inventory in Farms – The Example of an Organic Farming System

In organic farms, the internal carbon fluxes are of great importance. They are connected with soil fertility (humus contents, biological activity, soil structure) and the yield potential; some C pools (C fixation in humus) and C fluxes (CO2 and CH4 emissions) may affect the environment. The approach used in the described model software allows to quantify management related and site dependant C fluxes and also the resulting emissions as starting point for an inventory of emissions from farms. The software was validated on the basis of intensive investigations made in the Experimental Farm Scheyern over many years. The results corresponded well to the measured values and characterize Scheyern as a farming system of intensive ecological shaping

Vergleich zweier Humusbilanzmethoden in der praktischen Anwendung

Humus balance methods are used to estimate the humus situation on arable land of a farm. Guarantee for a stable yield is a sufficient supply of humus. There for it is necessary to use the appropriate balance method. The humus balance method from Leithold has been compared with the one that is described at Hülsbergen (2002) by using the Software Model REPRO. The humus balances of the investigated farm increased continuous throughout the study period. Based on the entire study period the humus supply increased 4 percentage points per year from 70% to 125%. The results of this study leads to the conclusion that improving the humus supply primarily resulted in the increase of livestock. The intensification of milk production has improved the supply of humus. Basically, it can be stated that the use of both methods has led to similar statements regarding the development of the farm

Relationships between tree and soil properties in Picea abies and Pinus sylvestris forests in Sweden

The exchange of elements between plants and the soil in which they are growing creates reciprocal control of their element composition. Within plants, the growth rate hypothesis from ecological stoichiometry implies a strong coupling between C, N, and P. No similar theory exists for predicting relationships between elements in the soil or relationships between plants and the soil. We used a data set of element concentrations in needles and humus of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) forests in Sweden to investigate the extent to which relationships between elements (C, N, P, S, K, Ca, Mg, Fe, Mn, Al) can be observed within and between plants and soils. We found element composition to be more strongly controlled in needles than in humus. Elements that are covalently bound were also more strongly controlled, with no apparent differences between macro- and micronutrients. With the exception of N/C, there were surprisingly few relationships between elements in needles and humus. We found no major differences between the two tree species studied, but investigations of additional forest types are needed for firm conclusions. More control over element composition was exercised with respect to N than C, particularly in needles, so it might be advantageous to express nutrient concentrations relative to N rather than on a dry weight or carbon basis. Variations in many ecosystem variables appeared to lack ecological significance and thus an important task is to identify the meaningful predictors