We investigated the relevance of understory vegetation in indicating site productivity as expressed by sessile oak (Quercus petraea Matt. Liebl.) site index over a large territory. The relationships ...between site index and (1) understory vegetation or (2) soil, topography and climate were studied using data from 99 even-aged high-forest stands located in northern France. Multiple regressions using floristic indices as predictors explained the same part of variance in site index as regressions using climate, topography, and soil factors (R2 = 0.49 to 0.60). However, better models were obtained by combining floristic and abiotic variables (R2 = 0.57 to 0.69). We concluded that (1) site productivity can be assessed with the same precision using understory vegetation or abiotic variables separately, even over a large region, but (2) it would be more appropriate to combine soil physical and chemical properties, climate and topography with floristic indices to estimate sessile oak site index.
La végétation du sous-bois peut-elle prédire correctement l'indice de fertilité ? Comparaison de l'efficacité des indices floristiques et abiotiques en futaie régulière adulte de chêne sessile dans la moitié nord de la France. L'objectif était d'étudier sur un vaste territoire la pertinence de la végétation du sous-bois pour prédire le niveau de productivité d'un peuplement, mesurée par l'indice de fertilité du chêne sessile (Quercus petraea Liebl.). Les relations entre cet indice et (1) la végétation du sous-bois ou (2) le climat, la topographie et le sol ont été étudiées sur 99 peuplements adultes de futaie régulière situés dans la moitié nord de la France. Les régressions multiples basées sur ces indices floristiques expliquent la même part de variance de l'indice de fertilité que les régressions basées sur le climat, la topographie et le sol (R2 = 0,49 à 0,60). Cependant, de meilleurs modèles sont obtenus en combinant les variables floristiques et abiotiques (R2 = 0,57 à 0,69). Nous concluons que la productivité d'une essence peut être évaluée avec le même niveau de précision en utilisant séparément la végétation du sous-bois et les descripteurs abiotiques, y compris sur un vaste territoire. Mais nous recommandons pour une meilleure estimation de combiner à la fois les propriétés physiques et chimiques du sol, le climat, la topographie et les indices floristiques.
The ability to establish cover using grass and legume species without any soil preparation was studied in a barren materials
quarry. The biodiversity indexes (Simpson) during the growing season as ...well as the vegetation cover and composition were
measured. The results showed that the established species had a satisfactory cover (up to 87.5%). This means that we can achieve
significant soil rehabilitation after mining using herbaceous plant cover and reduce the cost of rehabilitation by cutting the expenses
of soil preparation.
Soil preparation by ploughing in the floodplain forest and its influence on vegetation and primary soil characteristics Libus, J.,Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Ustav Zakladani a Pesteni Lesu; Mauer, O.,Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Ustav Zakladani a Pesteni Lesu; Vavricek, D.,Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Ustav Geologie a Pedologie
Journal of forest science (Praha),
(Apr 2010), Volume:
56, Issue:
4
Journal Article
Peer reviewed
Open access
The paper analyzes the effect of whole-area site preparation by ploughing and of alternate field and forest crops on the understorey, soil biological activity and physical and chemical ...characteristics in the commercial forest. Another factor of the study was to assess the effect of the clearcut size on forest stands. Analyzed were 20-years-old stands of pedunculate oak on alluvial sites 1L9 (Fraxino pannonicae-Ulmetum). It can be deduced from the analyses that after twenty years neither different site preparation nor clearcut size affected the understorey and soil biological activity. Field crops and forestry in alternation had a significantly adverse effect on porosity and water-retention capacity in the lower layer of top soil (25-30 cm). Whole-area ploughing had a negative influence on the loss of organic substances due to accelerated mineralization. Nevertheless, the observed differences are not significant; the values did not fall below critical limits and in no case did they affect other studied site characteristics or the development of root systems and aboveground parts of oak trees.
Con el objetivo de evaluar un método alternativo para la cuantificación de diferentes formas de nitrógeno, se determinó la concentración de nitratos (NO3-) y amonio (NH4+) por dos métodos: ...Colorimetría y Electrodo de Ión Selectivo (EIS), en muestras de suelos cultivados con flores o banano en el departamento de Antioquia, Colombia. Se realizaron análisis de regresión y correlación para las concentraciones obtenidas por los dos métodos, que mostraron una asociación altamente significativa entre ellos. La determinación de NO3- mediante la formación de complejo coloreado con brucina ácida o mediante el uso de un electrodo selectivo para nitratos presentó un coeficiente de determinación altamente significativo (R² = 99,2). En forma similar, la determinación de NH4+ basada en la formación de complejo coloreado azul de indofenol ó utilizando el electrodo para amoniaco presentó un valor de R² = 98,4. El uso de electrodos presenta ventajas en comparación con las técnicas colorimétricas, que requieren mucho más tiempo y equipos mas costosos.In order to evaluate an alternative method for quantifying different forms of nitrogen, the concentrations of nitrates (NO3-) and ammonium (NH4) were determined by two methods: Colorimetry and Ion Selective Electrode (ISE), in soil samples from soils cultivated with flowers or banana in the department of Antioquia,Colombia. Regression and correlation analyses on the concentrations obtained from the two methods showed highly significant relationships among them. The determination of NO3- by means of colored complexes with brucine acid or by means of the use of an electrode selective for nitrates exhibited a highly significant coefficient of determination (R² = 99.2). In a similar way, determination of NH4 based on the formation of blue colored complexes of indophenol or employing the electrode for ammoniac yielded a value of R² = 98.4. The use of electrodes has advantages over the colorimetric techniques, that require much more time and more costly equipment.
The monitoring was carried on in the years 1996-2000 in the international IOSDV (Internationale Ökologische Stickstoff Dauer Versuche) field trial running since 1983 in Lukavec, Pelhřimov district. ...In the given locality, there are low fertility sandy-loamy cambisoils, long-term average annual rainfall 653 mm, average annual temperature 7°C, altitude 620 m. In the field trials there were introduced different organic fertilizations and graduate N-doses. According to the complex diffusion analysis, statistically significant for the yields of winter wheat after potatoes was the impact of N fertilization, years, and double interactions, with the exception of different organic fertilization. The N doses up to 120 kg.ha-1 after potatoes proved to be optimal from the viewpoint of winter wheat yields and quality. The situation was similar for winter barley. The results of diffusion analysis for individual years were analogical also in straw yields of both cereals. The highest N dose to potatoes (200 kg.ha-1) resulted in the highest tuber yields, but the starch content was significantly lower. Graduated N doses increased in cereals the numbers of ears per m2, but the mass of 1000 grains mostly decreased. In addition, N content in grain and straw increased with N doses, while pH annually decreased by 0.1 to 0.4. On plots without organic fertilization the N-balance was equilibrated with the annual application of 120 kg N.ha-1 with straw embedding after cereals at 90 kg N.ha-1 and on plots with stall dung to potatoes already at 70 kg N.ha-1. On plots without N fertilization, the balance was passive also in P and K on plots without organic fertilization. A balance surplus was obtained already with the annual application of 15 kg P.ha-1 and 83 kg K.ha-1 and organic fertilization. With the annual fertilization with 22 kg P.ha-1 and 83 kg K.ha-1 and stall dung (30 t.ha-1) once every three years the P and K content increased annually by 1 to 3 mg.kg-1 of soil. Maximum levels of crop growing profitability were obtained with those doses of fertilizers with which also an equilibrated balance of nutrients was obtained.
The monitoring was carried on in the years 1996-2000 in the polyfactorial P-A field trial in Lukavec, Pelhřimov district. The given locality is characterized by low fertility sandy-loamy cambisoils, ...by long-term average annual rainfall of 653 mm, by average annual temperature of 7°C and its altitude is 620 m. The field trial included different organic fertilizations; graduate N-doses, different soil tillage as well as different forecrops. It manifested in this group of field trials that the forecrop value of red clover and dung manured potatoes before winter wheat was practically the same in the given locality. The optimal N dose for potato yields was about 80 kg N.ha-1. In oats the yields after red clover with using the Horsch system in spring were significantly lower than after embedding of red clover in autumn. In cereals, graduated N doses increased the numbers of ears (panicles) per m2, but the mass of 1000 grains often decreased. In addition, N content in grain and straw increased with N doses, while pH annually decreased by 0.1 to 0.4.
The aim of this study is to determine the availability of cadmium (Cd) in the soil of Yonne district, Burgundy, France. Soil samples were collected from surface-ploughed layer in fields across the ...southern part of the Yonne district, Burgundy, France. Some results analysing soil Cd and Cu contents on Domérien region of Burgundy has been presented. This is to know the relationship between extracting time and extracted Cd and Cu contents from the two sites’ soils (Dubloc, Bierry) in the Domérien soil series. A total of 68-107% Cd and 20-28% Cu were extracted from the soil in 1440 min. The two soils were acidic, and around 70% of Cd contents were extracted in 20 min of extraction, while around 65% of Cu contents were extracted in 30 min of extraction. The Cd extraction was blocked at the mid-extraction time, while the Cu extraction kept on increasing up to the end of the extraction time. Cadmium extraction increased with increase in pH value in the present experiment. Copper content shows same tendency with Cd.
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