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41.
Javier Gonzalez-Romero Demetrio Antonio Zema Bruno Gianmarco Carrà Jonay Neris Alvaro Fajardo Pedro Antonio Plaza-Álvarez Daniel Moya Esther Peña-Molina Jorge de las Heras Manuel Esteban Lucas-Borja 《Soil Use and Management》2023,39(2):881-899
Soil erosion modelling applied to burned forests in different global regions can be unreliable because of a lack of verification data. Here, we evaluated the following three erosion models: (1) Water Erosion Prediction Project (WEPP), (2) Morgan-Morgan-Finney (MMF) and (3) Universal Soil Loss Equation-Modified (USLE-M). Using field plots that were either untreated or mulched with straw, this study involved observations of soil loss at the event scale at a burned pine forest in Central Eastern Spain. The erosion predictions of the three models were analysed for goodness-of-fit. Optimization of the MMF model with a new procedure to estimate the C-factor resulted in a satisfactory erosion prediction capacity in burned plots with or without the mulching treatment. The WEPP model underestimated erosion in the unburned areas and largely overestimated the soil loss in burned areas. The accuracy of soil loss estimation by the USLE-M model was also poor. Calibration of the curve numbers and C-factors did not improve the USLE-M model estimation. Therefore, we conclude that an optimized MMF model was the most accurate way to estimate soil loss and recommend this approach for in Mediterranean burned forests with or without postfire mulching. This study gives land managers insight about the choice of the most suitable model for erosion predictions in burned forests. 相似文献
42.
Loquat [Eriobotrya japonica (Thunb.) Lindl.] is a minor fruit-tree species which is grown commercially in the Mediterranean region. Given the current increase in loquat cultivation, there is a need to define basic crop-management procedures in order to obtain high yields and optimal fruit quality. The aim of this work was to develop a routine for loquat farmers to follow, in order to know the nutritional status of trees in order to establish a rational fertilization regime, and to correct nutrient deficiencies as soon as possible. This paper reports three experiments aimed at establishing: 1) leaf type, 2) time of leaf sampling and 3) the standard leaf nutrient levels as a function of maximum yield. Results indicate that the summer flush leaves could be the most representative of nutritional status. Thus, the most appropriate time to sample leaves for analysis is in summer (beginning of August to the end of September), taking mature 3–4 month old leaves. 相似文献
43.
Gamarra Delia Gamarra Villar Charo Milagros Suarez Gilberto Torres Esteban Walter Darlyn Ingaruca Contaldo Nicoletta Lozano Emerson Clovis Carrasco Bertaccini Assunta 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(1):223-235
European Journal of Plant Pathology - Corn plants showing symptoms of midribs chlorosis, and leaf reddening, short internodes, ear proliferation, and plant growth reduction were collected in Peru... 相似文献
44.
Simulated nitrogen deposition affects soil fauna from a semiarid Mediterranean ecosystem in central Spain 总被引:1,自引:0,他引:1
Raúl Ochoa-Hueso Iluminada Rocha Carly J. Stevens Esteban Manrique María José Luciañez 《Biology and Fertility of Soils》2014,50(1):191-196
Nitrogen (N) deposition is a major threat to the semiarid Mediterranean ecosystems. We simulated a gradient of N deposition (0, 10, 20 and 50 kg N ha?1 year?1?+?6.4 kg N ha?1 year?1 ambient deposition) in a Mediterranean shrubland from central Spain. In autumn 2011 (after 4 years of experimental duration), soil cores were taken to extract the soil fauna. Acari (45.54%) and Collembola (44.00%) were the most represented taxonomical groups, and their abundance was negatively related to soil pH. Simulated N deposition had an impact on the total number of individuals in soil as well as on Collembola and Pauropoda abundance. Collembola abundance increased with N loads up to 20 kg N ha-1 year-1 and then decreased. This response was attributed to soil acidification (between 0 and 20 kg N ha-1 year-1) and increased soil ammonium (between 20 and 50 kg N ha-1 year-1). Pauropoda were favoured by additions of 50 kg N ha-1 year-1, and it was the only taxonomical group whose abundance was exclusively related to N deposition, suggesting their potential as bioindicators. Contrary to predictions, there was a negative relationship between soil faunal abundance and plant diversity. In conclusion, soil faunal communities from semiarid Mediterranean ecosystems in central Spain seem to be primarily influenced by soil chemistry (mainly pH) but are also susceptible to increased N deposition. The main drivers of change under increased N deposition scenarios seem to be soil acidification and increased ammonium in soils where nitrate is the dominant mineral N form. 相似文献
45.
Esteban R Jiménez ET Jiménez MS Morales D Hormaetxe K Becerril JM García-Plazaola JI 《Tree physiology》2007,27(10):1407-1414
Two xanthophyll cycles have been described in higher plants: the violaxanthin xanthophyll (V or VAZ) cycle, which is present in all species, and the taxonomically restricted lutein epoxide xanthophyll (Lx) cycle, which involves the light-induced de-epoxidation of Lx to lutein (L) and its epoxidation back to Lx in low light. Laboratory experiments indicate that the first reaction occurs quickly, but the second reaction is much slower. We investigated the Lx cycle under field conditions in several tree species of the Lauraceae family to determine its relationship with the ubiquitous V cycle. The field study was conducted in two natural laurel forests: one in the Canary Islands, where Laurus azorica (Seub.) Franco, Ocotea foetens (Aiton.) Benth, Apollonias barbujana (Cav.) Bornm. and Persea indica (L.) Spreng were studied; and one in the Basque Atlantic coast where Laurus nobilis L. was studied. The results were complemented by a taxonomic study. The presence of Lx was widespread among Lauraceae species, but its concentration varied even among closely related species. The V pool size correlated positively with growth irradiance, whereas the relationship between Lx pool size and growth irradiance varied with species. A functional Lx cycle was confirmed under field conditions only in O. foetens and L. nobilis. Furthermore, in O. foetens, a correlation between Lx de-epoxidation and photoinhibition suggested a protective role for this cycle. We conclude that, unlike the V cycle, which is normally correlated with irradiance, the operation and light dependence of the Lx cycle is species-dependent. 相似文献
46.
de Almeida Daniel Mageste Marcondes Marcos Inácio Rennó Luciana Navajas Pereira Silva Luiz Henrique Martins Leandro Soares Marquez David Esteban Contreras Castaño Villadiego Faider Alberto Velez Saldarriaga Felipe Franco Julian David Castaño Moreno Deilen Paff Sotelo de Moura Felipe Henrique Paulino Mário Fonseca 《Tropical animal health and production》2019,51(1):79-87
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of strategic supplementation in the dry period and dry/rainy transition period on the performance and... 相似文献
47.
Agustina Anson Carina Strohmayer Jose M. Larrinaga Esteban Iglesias Ramon Almela Gustavo Ramírez Vicente Cervera 《Veterinary radiology & ultrasound》2019,60(6):E66-E70
A one‐year‐old intact male German shepherd dog was referred with a 3‐month history of dysuria and pollakiuria. Physical examination revealed a large firm mass in the caudal abdomen. Findings from survey radiography, negative contrast cystography, computed tomographic (CT) retrograde positive contrast cystography, and CT excretory urography were consistent with a large urinary bladder diverticulum. An exploratory laparotomy revealed a normal wall appearance in the ventral compartment (true bladder) and marked thinning of the wall in the dorsal compartment (diverticulum). Both ureters inserted into the ventral compartment. The dorsal compartment was excised and histopathology confirmed the diagnosis of urinary bladder diverticulum. 相似文献
48.
Daniel Mageste de Almeida Marcos Inácio Marcondes Luciana Navajas Rennó Lívia Vieira de Barros Carla Heloísa Avelino Cabral Leandro Soares Martins David Esteban Contreras Marquez Felipe Vélez Saldarriaga Faider Alberto Castaño Villadiego Manuela Acevedo Cardozo Roman Maza Ortega Javier Enrique Garces Cardenas Virginia Lucia Neves Brandão Mário Fonseca Paulino 《Tropical animal health and production》2018,50(8):1771-1777
Beef cows’ milk yield is typically determined by measuring milk yield once daily and then doubling this value to estimate daily production. However, it is not known whether this is accurate. Thus, we aimed to determine the association between morning and afternoon milk yield in grazing Nellore cows. Eighty Nellore cows were used, with initial weight of 516.0?±?1.0 kg. The experiment was a completely randomized factorial scheme, with 20 replications and four treatments (i.e., +?or ??pre-partum supplementation in combination with +?or ??post-partum supplementation): PRMM—1 kg of supplement/cow/day for 90 days pre-partum; MMPS—1 kg of supplement/cow/day for 90 days post-partum; PRPS—1 kg of supplement/cow/day for 90 days pre-partum and 90 days post-partum; and MM—only mineral mix ad libitum during pre- and post-partum. Milk was sampled on days 45, 135, and 225 post-partum (early, middle, and late lactation, respectively). No effects were observed of pre- and post-partum supplementation on milk yield (P?>?0.05). The afternoon/morning proportion of 0.45 in the early third of lactation was higher than other stages, which had a proportion of 0.41 (P?<?0.05). Post-partum supplementation increased milk protein in the morning and afternoon milking (P?<?0.05). There was also no effect of pre- and post-partum supplementation on afternoon-morning proportion other milk components (P?>?0.05). We conclude that estimating daily milk production of grazing beef cattle by multiplying a once daily milking amount times two is not accurate. Under the conditions of this study, proportion of total daily production represented by the ratio of afternoon/morning milking was 0.45 in early lactation (first third) and 0.41 in mid- and late lactation. 相似文献
49.
The morphology–diet relationship and its role in the coexistence of two species of annual fishes
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Friedrich W. Keppeler Luis Esteban K. Lanés Ana S. Rolon Cristina Stenert Pablo Lehmann Martin Reichard Leonardo Maltchik 《Ecology of Freshwater Fish》2015,24(1):77-90
Annual fishes, which inhabit temporary pools with extremely limited habitat complexity and niche availability, display remarkable sexual dimorphism, rapid growth, and enormous investment into reproduction, all traits associated with high energy requirement. This study tests three hypotheses for two syntopic annual fishes (Austrolebias minuano and Cynopoecilus fulgens) found in six wetlands of southern Brazil: (i) considerable morphological differences result in low dietary overlap, (ii) sexual dimorphism in both species leads to intraspecific diet segregation, and (iii) dietary richness increases during ontogenetic development, and is narrower in C. fulgens than A. minuano due to morphological limitations imposed by reduced size. The diet of 82 A. minuano and 211 C. fulgens individuals was analyzed over two annual cycles. The morphology was characterized by 26 measurements covering the entire body of both species. There was no evidence of morphological specialization related to food competition and the diet of A. minuano and C. fulgens showed high overlap. High food availability, high predator abundance, and high connectivity of adjacent wetlands are likely the main mechanisms allowing coexistence of both species. Within species, sexual dimorphism did not result in a decrease in dietary overlap, which reinforces the idea that morphological differences between the sexes did not evolve as a mechanism to decrease food competition. Large A. minuano did not have a more diverse diet than the smaller C. fulgens; however, increase in body size allowed both species to ingest larger prey. Morphological variability in both species was mainly related to ontogenetic development and reproduction. 相似文献
50.
The extract of the rootbark of Hippocratea volubilis afforded a new triterpene caffeoyl ester, lupeol caffeate (1). Its structure was determined by means of spectroscopic evidence. 相似文献