Search results for "forestry"

Die Wirkung von Säure und Aluminiumionen auf den Nährelementgehalt und den histologischen Zustand nichtmykorrhizierter Fichtenwurzeln (Picea abies [L…

1988

Dreijahrige Fichten wurden 2 Jahre lang in einer Spruhhydrokultur gehalten und anschliesend 6 Monate lang mit Nahrlosungen behandelt, die den Lysimeterlosungen unter Fichte im Solling entsprachen, wobei die pH-Werte auf 5.0, 3.5 und 2.5 eingestellt wurden. Ein Teil der Nahrlosungen mit pH 3.5 bzw. 2.5 wurde mit 1 oder 2 mmol Aluminium pro Liter angereichert. Die Ca- und Mg-Werte der Nadeln und Wurzeln sanken unter Saure- und Aluminiumseres nicht unter die Mangelgrenzen, auch wenn die Gehalte beider Elemente um bis zu 35% abnahmen. Weitere Veranderungen wurden fur Kalium, Phosphor und Aluminium beobachtet.

Investigation of European shot-hole borer, Xyleborus dispar (Coleoptera, Scolytidae), in apple orchards of Latvia

2015

European shot-hole borer is known to occur on a wide range of deciduous trees and frequently found on fruit trees in most of the Holarctic. During the last years increased activity of this beetle<em> </em>contributed necessity for investigation of it in apple orchards of Latvia. Because of the latent behavior it is difficult to control distribution of <em>Xyleborus dispar</em>. Often insecticides are not effective, especially if not used in an appropriate time and methods of integrated or biological plant protection are needed. In the current study, results of two year monitoring of <em>X. dispar</em> flying activity and effectiveness of two types of stic…

Mi.P.A.F. targeted project for evaluation of European and Japanese plum rootstocks in Italy: Results of six years of observations

2007

The Mi.P.A.F. (Italian Ministry of Agriculture) targeted project "National Lists of Recommended Rootstocks and Cultivars", coordinated by Prof. F. Loreti, University of Pisa, aims at evaluating the performance of fruit rootstocks introduced into the Italian nursery market. As part of this project, trials were established to compare some of the most interesting rootstocks for European and Japanese plum in 9 different locations in Italy. The rootstocks tested were: 'Citation-Zaipime', 'GF 31', 'Marianna GF 8/1', 'Ishtara-Ferciana', 'Jaspi-Fereley', 'Julior-Ferdor', 'Myrobalan 29C', 'Myrobalan B', 'MrS 2/5' and 'Myrocal'. In 1995, nine orchards were planted at 5 × 5 m spacing; in each orchard,…

Effect of primary mild stresses on resilience and resistance of the nitrate reducer community to a subsequent severe stress

2008

International audience; The factors regulating soil microbial stability (e.g. resistance and resilience) are poorly understood, even though microorganisms are essential for ecosystem functioning. In this study, we tested whether a functional microbial community subjected to different primary mild stresses was equally resistant or resilient to a subsequent severe stress. The nitrate reducers were selected as model community and analysed in terms of nitrate reduction rates and genetic structure by narG PCR-restriction fragment length polymorphism fingerprinting. Heat, copper and atrazine were used as primary stresses and mercury at a high concentration as a severe stress. None of the primary …

Effects of climate, land cover and topography on soil erosion risk in a semiarid basin of the Andes

2016

Understanding soil erosion processes in the Ecuadorian Andes with a tropical wet-dry climate and a variable topography, is fundamental for research on agriculture sustainable, environmental management, as well as for a stable water supply for the local populations. This work proposes method to estimate soil erosion risk in the semiarid Catamayo basin with limited data. The results show that the rainfall distribution and the erosivity along with the rugged topography, followed by the land cover (C-factor), are the most important factors to estimate soil erosion risk. The soil erodibility is the most important factor in the dry season for agricultural areas and where the ground cover is spars…

Crop Coefficient Curve for Paddy Rice from Residual Energy Balance Calculations

2017

AbstractThe crop coefficient (Kc) values of rice paddy are important for estimating accurate rice crop evapotranspiration (ETc), water transfers planning, efficient irrigation management, and hydrological studies. In this study, ETc was measured and a generalized Kc curve was calculated for paddy rice in the Sacramento Valley, California. Field experiments were conducted in three rice paddy fields during the 2011–2013 growing seasons. Surface renewal analysis, after calibration using eddy covariance method, was applied to obtain sensible heat flux values from high-frequency temperature readings; latent heat flux densities were characterized by the residual of the energy balance method. The …

Soil erosion and agriculture

2009

Role of rock fragment cover on runoff generation and sediment yield in tilled vineyards

2017

Summary The soil in conventional Mediterranean vineyards is an active and non-sustainable source of sediment and water. Lack of vegetation cover, small soil organic matter content and intense ploughing result in large rates of erosion in a millennia-old tillage system. There is a need for soil conservation strategies that enable sustainability of wine and grape production; therefore, it is essential to measure the rates and to investigate the processes and factors of soil erosion. This study evaluated factors that can reduce soil losses in traditional Mediterranean vineyards. The investigation was carried out with 96 rainfall simulation experiments at the pedon scale (0.24 m2) to measure so…

Developing an erodibility triangle for soil textures in semi-arid regions, NW Iran

2016

Abstract There is a strong need to develop a simple method for rapid estimation of erodibility using readily available data. In this study, soil erodibility was measured using eleven soil textures at the plot scale (60 cm × 80 cm) on a slope of 9% in a semi-arid region. A total of 110 soil erosion experiments were conducted using ten simulated rainfalls (50 mm h− 1 for 30 min). A regression model was developed based on silt and clay content (R2 = 0.82, p

Comparing different application procedures of the water drop penetration time test to assess soil water repellency in a fire affected Sicilian area

2019

Abstract The Water Drop Penetration Time (WDPT) technique was applied in two subsequent years (2016 and 2017) to check surface soil water repellency (SWR) in a Sicilian mountain area affected by a wildfire on June 2016. A total of 93 sites were sampled and from 3 to 100 droplets were used to characterize a site. The detected SWR varied with the severity of the wildfire, being practically absent in the unburnt control area and slight to extreme in the burnt areas. The percentage of extremely repellent sites increased with wildfire severity. SWR vanished one year after the passage of the fire in sites where fire severity was moderate but it persisted in the case of a severe wildfire. In gener…