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排序方式: 共有145条查询结果,搜索用时 15 毫秒
91.
An industrial-scale composting plant has been designed for producing organic fertilizers from olive mill waste using the windrow pile system. Materials to be composted, two phase olive mill waste (TPOMW) and sheep litter (SL), were characterized and made into three piles consisting of different proportions of each. Throughout the composting process, temperature (T), moisture (M), organic matter (OM), total organic carbon (Corg), total nitrogen (NT), germination index (GI), pH and electrical conductivity (EC) were monitored. The potential agronomic value of the final composts was ascertained by analyzing the bulk density, OM and Corg concentration, pH, EC, macro and micronutrient content (N, P, K, Ca, Mg, Fe, Cu, Mn, Zn, B), the concentration of humic and fulvic acids and inorganic nitrogen (NH4+,NO2?,NO3?). Each compost was applied to an area of one hectare within a six year-old olive plantation. Four months after application, the soils showed an increased OM concentration and cationic exchange capacity (CEC). 相似文献
92.
Alberto Gabino Martínez-Gutiérrez Angélica Bautista Cruz Cirenio Escamirosa Tinoco Juana Yolanda López Cruz Miguel Urrestarazu 《Journal of plant nutrition》2015,38(12):1877-1884
The bagasse of mezcal maguey and the fiber of coconut fruit are organic byproducts of the mezcal and copra agro-industries in Oaxaca, Mexico. The effects of different particle sizes and prior usage times as substrates on the production and quality of tomato (Lycopersicon esculentum Mill) were studied. Three independent and simultaneous experiments were conducted in multi-tunnel greenhouses. Three prior growing cycles of tomato crop, each 150 days in length days of use (DOU), were used for the usage time experiments with mezcal maguey bagasse as the growth medium. In the first experiment, tomato plants grown on substrate with 150 DOU produced the highest yields, the largest number of commercial quality fruits and the fewest non-commercial quality fruits. In the second experiment, the combination of fine particle size and maguey bagasse substrate with 150 DOU produced the highest yields. In the third experiment, fine and medium-sized particles of maguey bagasse and coconut fiber produced the highest yields. The data indicate that both coconut fiber and mezcal maguey bagasse can be used as substrates for tomato cultivation without affecting fruit quality; furthermore, the use of fine and medium-sized particles increases production. Maguey bagasse with up to 150 DOU as a substrate is best for culture, as prior usage beyond this length of time negatively affects production. 相似文献
93.
M. Pilar Bernal Antonio F. Navarro Asunción Roig Juan Cegarra Diego García 《Biology and Fertility of Soils》1996,22(1-2):141-148
Two types of compost, consisting of sweet sorghum bagasse with either sewage sludge or a mixture of pig slurry and poultry manure, were studied in a pilot plant using the Rutgers system. The total degradation of the piles as determined by the weight loss of organic matter during the bio-oxidative and maturation phases accounted for 64% of the organic matter applied and followed a first-order kinetic function. Concentrations of total and organic N increased during the composting process as the degradation of organic C compounds reduced the compost weight. Losses of N through NH3 volatilization were low, particularly in the compost with sewage sludge due to pH values of <7.0 and the low temperatures reached in the compost during the first 2 weeks. The C:N ratio in the two composts decreased from 24.0 and 15.4 to values between 12 and 10. Increases in cation exchange capacity and in fulvic and humic acid-like C revealed that the organic matter had been humified during composting. The humification index, the C:N ratio, fulvic:humic acid-like C, and cation exchange capacity proved to be the most suitable parameters for assessing the maturity of these composts. 相似文献
94.
Nutrient balances in calcareous soils after application of different rates of pig slurry 总被引:1,自引:0,他引:1
Abstract. Changes in amounts of macro-(N, P, K) and micro-nutrients (Fe, Mn, Zn and Cu) were determined in two calcareous soils amended over an eight-month period with pig slurry applications ranging from 0 to 500 m3 /ha, and planted in containers with green pepper ( Capsicum annuum ). Total N and exchangeable K increased after slurry applications of 300 m3 /ha or more, and available P increased after the smallest application rate (100m3 /ha). Maximum crop nutrient uptakes of 41, 40 and 91% for N, P and K occurred with the smallest dose of slurry. Large losses of N, ranging from 27 to 74% (mean 55%) of N added to soil, occurred with all slurry treatments. From 41 to 71% (mean 55%) of the total P added in pig slurry was fixed in non-assimilable forms. Most of the K from the pig slurry was available to the plants. Most of the micro-nutrients (Fe, Mn, Zn and Cu) from the slurry were immobilized in the soil, probably because of the high pH and the small amounts of organic matter in both the slurries and soils tested. 相似文献
95.
Clementina Barrera Bernal Gabriela Vázquez Icela Barceló Quintal Anne Laure Bussy 《Water, air, and soil pollution》2008,190(1-4):259-270
This study investigates the microalgal community dynamics associated with changes in municipal wastewater quality and discharges from the dairy industry in central Veracruz, Mexico, using an experimental stabilization-reactors system. Thirty one species of microalgae were recorded and 15 physicochemical variables were measured daily over 25 days in pretreated water. The biomass of microalgal groups displayed significant negative correlations with biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total suspend solids (TSS). Conversely, a significant positive correlation was found with dissolved oxygen, pH and nitrates. Using the Canonical Correspondence Analysis we identified an initial anaerobic phase (Phase I), characterized by high BOD, TSS and COD, ammonium and faecal coliforms. This was followed by a transition phase (Phase II), an initial aerobic phase (Phase III), when water quality improved considerably, and finally an aerobic phase (IV) with a high percent reduction in these parameters and almost complete organic load removal. The most abundant species associated with these phases were Arthrospira jenneri (Cyanophyceae) and Coccomonas sp. (Chlorophyceae) in Phase I; Polytomella sp. (Chlorophyceae) in Phase II; Polytoma tetraolare, Chlamydomonas caeca (Chlorophyceae) and some Cyanophyceae including Geitlerinema, Synechocystis, Cyanobium and Glaucospira in Phase III; Carteria sp. (Chlorophyceae), Lepocynclis ovum and Euglena clavata (Euglenophcyeae) in Phase IV. Maximum richness, diversity, and biomass levels occurred during the aerobic phase. Similar to other wastewater treatment systems the high succession rates decreased with reactor stabilization. These findings provide statistical evidence on the suitability of certain microalgae species as indicators of wastewater stabilization reactor status and effluent quality. 相似文献
96.
Martínez-Alcalá Isabel Clemente Rafael Bernal M. Pilar 《Water, air, and soil pollution》2009,201(1-4):283-293
Water, Air, & Soil Pollution - Chemical processes in the rhizosphere play a major role in the availability of metals to plants. The objective of this study was to assess the potential of white... 相似文献
97.
Bucci SJ Scholz FG Campanello PI Montti L Jimenez-Castillo M Rockwell FA Manna LL Guerra P Bernal PL Troncoso O Enricci J Holbrook MN Goldstein G 《Tree physiology》2012,32(7):880-893
Hydraulic traits were studied for six Nothofagus species from South America (Argentina and Chile), and for three of these species two populations were studied. The main goal was to determine if properties of the water conductive pathway in stems and leaves are functionally coordinated and to assess if leaves are more vulnerable to cavitation than stems, consistent with the theory of hydraulic segmentation along the vascular system of trees in ecosystems subject to seasonal drought. Vulnerability to cavitation, hydraulic conductivity of stems and leaves, leaf water potential, wood density and leaf water relations were examined. Large variations in vulnerability to cavitation of stems and leaves were observed across populations and species, but leaves were consistently more vulnerable than stems. Water potential at 50% loss of maximum hydraulic efficiency (P(50)) ranged from -0.94 to -2.44 MPa in leaves and from -2.6 to -5.3 MPa in stems across species and populations. Populations in the driest sites had sapwood and leaves more vulnerable to cavitation than those grown in the wettest sites. Stronger diurnal down-regulation in leaf hydraulic conductance compared with stem hydraulic conductivity apparently has the function to slow down potential water loss in stems and protect stem hydraulics from cavitation. Species-specific differences in wood density and leaf hydraulic conductance (K(Leaf)) were observed. Both traits were functionally related: species with higher wood density had lower K(Leaf). Other stem and leaf hydraulic traits were functionally coordinated, resulting in Nothofagus species with an efficient delivery of water to the leaves. The integrity of the more expensive woody portion of the water transport pathway can thus be maintained at the expense of the replaceable portion (leaves) of the stem-leaf continuum under prolonged drought. Compensatory adjustments between hydraulic traits may help to decrease the rate of embolism formation in the trees more vulnerable to cavitation. 相似文献
98.
Pérez-Torres S Flores-Pérez FI Orihuela A Aguirre V Bernal G Nieto A Vázquez R Solano JJ 《Tropical animal health and production》2012,44(3):383-384
To evaluate the level of stress induced by the tongue inspection method during cysticercosis diagnosis in pigs at 60 and 90 kg,
27 animals were assigned to one of three experimental groups. In the first group (T1), pigs were held with a snout noose.
In addition, animals in T2 were subjected to tongue inspection, while in T0, none of the procedures described above were performed.
Resistance to be handled and serum cortisol concentration were higher (P < 0.05) than those from T0 in T1 and T2 groups, for 60- and 90-kg pigs. Time to return to the feeder observed the same pattern
than previous variables in 60-kg pigs, but T1 and T0 were similar (P > 0.05) for the heavier animals. T2 did not build up a significant amount of stress with respect to T1, where only more (P > 0.05) vocalizations were emitted by 90-kg pigs. It was concluded that the use of snout noose induces major changes in some
behavioral and physiological measures of stress in swine, while the opening of the mouth including tongue inspection does
not contribute significantly to this effect. 相似文献
99.
Diego Bernal Joseph P. Reid Julie M. Roessig Shinsyu Matsumoto Chugey A. Sepulveda Joseph J. CechJr. Jeffrey B. Graham 《Fish physiology and biochemistry》2018,44(3):949-967
In fish, regional endothermy (i.e., the capacity to significantly elevate tissue temperatures above ambient via vascular heat exchangers) in the red swimming muscles (RM) has evolved only in a few marine groups (e.g., sharks: Lamnidae, Alopiidae, and teleosts Scombridae). Within these taxa, several species have also been shown to share similar physiological adaptations to enhance oxygen delivery to the working tissues. Although the hemoglobin (Hb) of most fish has a decreased affinity for oxygen with an increase in temperature, some regionally endothermic teleosts (e.g., tunas) have evolved Hbs that have a very low or even an increased affinity for oxygen with an increase in temperature. For sharks, however, blood oxygen affinities remain largely unknown. We examined the effects of temperature on the blood oxygen affinity in two pelagic species (the regionally endothermic shortfin mako shark and the ectothermic blue shark) at 15, 20, and 25 °C, and two coastal ectothermic species (the leopard shark and brown smooth-hound shark) at 10, 15, and 20 °C. Relative to the effects of temperature on the blood oxygen affinity of ectothermic sharks (e.g., blue shark), shortfin mako shark blood was less affected by an increase in temperature, a scenario similar to that documented in some of the tunas. In the shortfin mako shark, this may act to prevent premature oxygen dissociation from Hb as the blood is warmed during its passage through vascular heat exchangers. Even though the shortfin mako shark and blue shark occupy a similar niche, the effects of temperature on blood oxygen affinity in the latter more closely resembled that of the blood in the two coastal shark species examined in this study. The only exception was a small, reverse temperature effect (an increase in blood oxygen affinity with temperature) observed during the warming of the leopard shark blood under simulated arterial conditions, a finding that is likely related to the estuarine ecology of this species. Taken together, we found species-specific differences in how temperature affects blood oxygen affinity in sharks, with some similarities between the regionally endothermic sharks and several regionally endothermic teleost fishes. 相似文献
100.
Rodríguez R Prieto-Montaña F Montes AM Bernal LJ Gutierrez-Panizo C Ayala I 《Avian diseases》2004,48(2):405-409
The mean duration and amplitudes of the lead II electrocardiogram were determined in the peregrine falcon (Falco peregrinus brookei) using 10 birds ranging in age from 1 to 5 yr. Electrocardiograms were performed on unanesthetized falcons in order to avoid the anesthesia effect on the electrocardiogram, by a method which seems to induce a tonic immobility-like reaction. All the falcons had a normal sinus rhythm, with a mean heart rate of 268 beats per minute. Mean durations of PR, ST, QT, and RR intervals were higher (but not statistically significant) in females than in males, except for the ST segment, with similar values in both sexes. P-wave deflections were positive in I, II, III, aVL, and aVF and negative in aVR. The normal patterns of wave forms of the QRS complexes in all leads were of QS and rS types, except for aVR and aVL, which presented an R configuration. The mean electrical axis was negative, with an average of -99.9 degrees. T-wave deflections were positive in I, II, III, and aVF leads II and negative in aVR and aVL. The data collected in this study may serve as a guide for electrocardiographic monitoring of peregrine falcons. 相似文献