Soil C and N dynamics, nutrient leaching and fertility in a pine plantation amended with wood ash under Mediterranean climate     

María Xesús Gómez-Rey  Manuel Madeira  João Coutinho 《European Journal of Forest Research》2013,132(2):281-295

Wood ash addition to forest soils can balance exported nutrients by tree harvesting and decrease soil acidity, but its effectiveness in Mediterranean areas has been scarcely evaluated. The aim of the present study was to assess the effects of wood ash application on soil C and N dynamics, nutrient leaching and fertility in a pine stand. Treatments were loose and pelleted ash application (11 Mg ha^?1), alone or combined with N fertilizer, and a control treatment. Nutrient leaching and soil chemical and biological properties were periodically evaluated for a 30-month period. Wood ash increased leaching of base cations (Ca, Mg, Na and K) and P, mainly at the beginning of the study. The effect was more pronounced for the loose formulation. As a consequence, a positive effect on soil nutrient availability (exchangeable base cations and extractable P) and soil acidity reduction was observed for the loose formulation in the 0–10-cm soil layer. Carbon and N dynamics were only affected when ash was applied with N fertilizer, which enhanced CO₂ flux during the study period.  相似文献   

Do harrowing and fertilisation at middle rotation improve tree growth and site quality in <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> Labill. plantations in Mediterranean conditions?     

Manuel Madeira  António Fabião  Marta Carneiro 《European Journal of Forest Research》2012,131(3):583-596

Effects of harrowing and fertilisation on tree growth, understory vegetation, forest floor litter and soil properties were studied in a field experiment installed in a 5-year-old first rotation eucalypt plantation. The treatments were harrowing (H), fertilisation (F), harrowing and fertilisation (HF) and a control without any treatments (C), with four replicates. Tree growth, root mass, tree nutrition status, understory vegetation, mass of forest floor litter and soil physical and chemical properties were monitored till the end of the rotation (stand was 14-year old). Effects of treatments on tree growth, root mass and timber production were not significant. Root nutrient concentration differed between treatments only few months after the beginning of the experiment, while differences regarding specific root length and area were observed during the first year. Harrowing (H and HF) led to significantly smaller biomass of understory vegetation (<13.4 g m⁻²) than other treatments (33−61 g m⁻²) during the first 3 years, but at the end of the experiment differences were less important. Forest floor litter mass after 3 years and at the end of the experiment were similar among treatments. Soil bulk density significantly decreased by harrowing (H and HF treatments), but 16 months after treatments were similar. Although soil chemical properties were not significantly affected by treatments, a decrease in base cations occurred during the rotation period. Fertiliser application is a questionable practice under the economic point of view, whereas harrowing can reduce the fuel load only during a short period, without negative effects on productivity and soil quality.  相似文献   

Carbon fractions as indicators of organic matter dynamics in chestnut orchards under different soil management practices     

Olga Borges  Fernando Raimundo  João Coutinho  Berta Gonçalves  Ivo Oliveira  Afonso Martins  Manuel Madeira 《Agroforestry Systems》2018,92(2):301-310

Several studies have emphasized the negative impact of the conventional soil management (CT) system on productivity and sustainability of chestnut orchards (Castanea sativa Mill.) when compared to no-tillage with grass cover (NT). However, scarce information is available regarding the effects of these soil management systems on soil organic matter (SOM) dynamics and soil quality. SOM or soil organic carbon is a key component of soil quality and has different fractions with different lability, namely, organic C (POC), active C (AC) and hot-water extractable carbon (HWC). These are considered as indicators of changes in management-induced soil quality. Thus, a study was carried out to evaluate the effects of NT and CT systems applied in the chestnut orchards on: (i) total amount of soil organic C (TOC), including C from both organic and mineral layers; (ii) soil organic C concentration of mineral horizons (OC); (iii) labile soil organic fractions (POC, AC, HWC); (iv) and soil mineral-associated C. The study was developed in two 30-year old chestnut orchards located in Northeast Portugal, that were kept under different soil management systems (NT or CT) during the preceding 17 years. Soil samples were taken at 0–10 and 10–20 cm soil depth. No significant differences in OC concentration were observed between NT and CT, while TOC was significantly higher in NT than in CT (22.54 and 12.17 Mg/ha or 34.16 and 22.90 Mg/ha, considering the organic layer plus mineral layers at 0–10 and 0–20 cm depth (set of two depths). The NT practice led to significantly higher concentration of labile C fractions (POC, AC and HWC) than CT at 0–10 cm soil depth. These results indicate that measurement of labile soil organic C fractions, such as POC, AC and HWC, may provide a sensitive and consistent indication of changes in soil C and SOM dynamics in response to soil management practices. Overall, NT seems to ensure better soil quality than CT in chestnut orchards under Mediterranean climate conditions.  相似文献   

High incidence of single nucleotide polymorphisms in the prion protein gene of native Brazilian Caracu cattle     

W.A. Kues  R.D. Ollhoff  J.W. Carnwath  F.P. de Souza  H.M.F. Madeira  & H. Niemann 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2006,123(5):326-330

Different alleles of the human and ovine prion protein gene correlate with a varying susceptibility to transmissible spongiform encephalopathies. However, the pathogenic implications of specific polymorphisms in the bovine prion protein gene (PRNP) are only poorly understood. Previous studies on the bovine PRNP gene investigated common European and North American cattle breeds. As a consequence of decades of intensive breeding for specific traits, these modern breeds represent only a small fraction of the bovine gene pool. In this study, we analysed PRNP polymorphisms in the native Brazilian Caracu breed, which developed in geographical isolation since the 16th century. A total of 10 single nucleotide polymorphisms (SNPs) were discovered in the coding region of the Caracu PRNP gene. Eight of the SNPs occurred at high frequencies in Caracu cattle (variant allele frequencies = 0.10–0.76), but were absent or only rarely observed in European and North American breeds. One of the Caracu SNPs was associated with an amino acid exchange from serine to asparagine (f = 0.17). This SNP was not detected in Holstein–Friesian, Simmental and German Gelbvieh and was only rarely detected in beef cattle (f = 0.01). We found 17 haplotypes for PRNP in the Caracu breed.  相似文献   

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil     

Madeira NG  Amarante AF  Padovani CR 《Tropical animal health and production》2000,32(4):225-232

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

Species richness and biomass of understory vegetation in a Eucalyptus globulus Labill. coppice as affected by slash management     

M. Carneiro  A. Fabião  M. C. Martins  C. Cerveira  C. Santos  C. Nogueira  M. Lousã  L. Hilário  André Fabião  M. Abrantes  M. Madeira 《European Journal of Forest Research》2007,126(4):475-480

The aim of this study was to assess the effect of different slash management practices on understory biodiversity and biomass in Eucalyptus globulus coppices in Central Portugal. The experiment consisted of four treatments: (a) removal of slash (R), (b) broadcast over the soil (S), (c) as in S but concentrating woody residues between tree rows (W) and (d) incorporation of slash into soil by harrowing (I). Understory vegetation was surveyed during 1–6, 9, and 10 years, the proportion of soil cover by plant species estimated, and diversity and equitability indexes determined. Above ground understory biomass was sampled in years 2–6, 9, and 10. The highest number of species in most years occurred in plots where slash was removed. Differences between treatments in the proportion of plant soil cover were never significant, whereas differences in diversity index were only occasionally significant and apparently related to the number of species. Thus, differences in the equitability index were not significant. Understory biomass did not decrease during the rotation period, and was usually highest in R and I, and lowest in S, but not significantly different. At the end of the rotation period, understory biodiversity indices and biomass were apparently independent of slash treatment.  相似文献   

Heparin binding proteins from Leishmania (Viannia) braziliensis promastigotes     

Azevedo-Pereira RL  Pereira MC  Oliveria-Junior FO  Brazil RP  Côrtes LM  Madeira MF  Santos AL  Toma L  Alves CR 《Veterinary parasitology》2007,145(3-4):234-239

  相似文献   

Histological studies of retroperitoneal lymphatic vessels in Cebus apella     

V de Freitas  V Dall Pai  E Gagete  M C Madeira  J E Moreira  G Seullner 《Anatomia, histologia, embryologia》1984,13(4):360-364

A histologic study of the retroperitoneal lymph vessels was carried out in the tufted capuchin (Cebus apella). The organization of the intima, media and surrounding adventitia is compared with that of other animals and man.  相似文献   

Root system of Quercus suber L. seedlings in response to herbaceous competition and different watering and fertilisation regimes     

Elena Cubera  Gerardo Moreno  Alejandro Solla  Manuel Madeira 《Agroforestry Systems》2012,85(2):205-214

Different management practices are commonly applied to increase pasture yield of Mediterranean open woodlands, but the consequences of increasing competition for soil resources with these practices on tree recruitment are still unknown. In a greenhouse study, belowground competition of Quercus suber L. seedlings growing together with natural (Oak_NP) or improved pasture (Oak_IP) was evaluated, and their root systems compared with those of seedlings growing in bare soil (Oak_BS). Two watering levels and two regimes of P₂O₅ fertilisation were also tested. Because of competition, the Oak_IP seedlings had their fine root mass density, coarse root length, and shoot mass reduced by up to 40, 36, and 39%, respectively, when compared to Oak_NP seedlings. Oak_NP and Oak_BS seedlings showed similar average root density parameters and shoot mass values, indicating that Q. suber seedlings growing with natural pasture is a low competitive system. High availability of water and phosphorus did not mitigate the strength of competition between herbaceous plants and oak seedlings, and favoured the pasture to the detriment of the trees. Our findings suggest that P₂O₅ fertilisation and irrigation practices performed to improve herbaceous productivity will negatively influence recruitment of Q. suber seedlings.  相似文献   

Productivity,nutrient immobilization and soil chemical properties in an Eucalyptus globulus plantation under different irrigation and fertilization regimes     

M. Madeira  J. S. Pereira 《Water, air, and soil pollution》1990,54(1):621-634

To evaluate the influence of irrigation and fertilization on the productivity of E. globulus a field experiment was started in 1986 in Central Portugal. The nutrients accumulated in the biomass and their allocation to the various biomass components as well as the changes in soil chemical characteristics were also followed. Irrigation and fertilization resulted in a significant increase of biomass production during the first 2 yr. A similar trend occurred with the net primary production and leaf litterfall. The differences between treatments in the amounts of accumulated nutrients in the aboveground biomass were similar to those of biomass accumulation. However, there was a small but consistent effect related to the average concentration of nutrients in the plant tissues. This effect occurred essentially in the leaves and branches. The concentration of N and P in the leaf litterfall was higher in the fertilized treatments than in the others. Fertilization alone induced a slight increase in the soil pH values, C content, exchangeable Ca and available P levels. Such increase was more pronounced in the fertilized with dripping irrigation treatment. This was due to the accumulation of nutrients in the wetted soil volume.  相似文献