垃圾填埋沼气的收集、净化与利用综述   总被引：9，自引：0，他引：9  

石磊  赵由才  唐圣钧 《中国沼气》2004,22(1):14-17

垃圾填埋沼气的回收利用是一项经济可行且对环境有益的技术.本文从填埋沼气的组成及其影响因素出发,探讨了沼气的收集、输送和贮存途径,介绍了当前的净化工艺,最后总结介绍了几种填埋沼气利用技术的特点及其适用性,并提出建立配备填埋沼气回收装置的卫生填埋场应成为我国城市垃圾处理的发展方向.  相似文献   

Monitoring forage production for farmers’ decision making     

Gonzalo Grigera  Martín OesterheldFernando Pacín 《Agricultural Systems》2007

Objective management of grazing livestock production systems needs monitoring of forage production at the managerial unit level. Our objectives were to develop a system that routinely estimates forage above-ground net primary production (ANPP) at the spatial and temporal resolution required by farmers in the Pampas of Argentina, and to facilitate adoption of the system by end users as a managerial support tool. Our approach was based on the radiation use efficiency (RUE) logic, which proposes that ANPP is determined by the amount of photosynthetically active radiation absorbed by the canopy (APAR), and the efficiency with which that energy is transformed in above-ground dry matter (radiation use efficiency, RUE). APAR is the product of incoming photosynthetically active radiation (PAR) and the fraction absorbed by the canopy (fPAR). We estimated fPAR as a non-linear function of MODIS normalized difference vegetation index (NDVI). RUE was empirically estimated for the two principal forage resources of the region, yielding the following relations: ANPP = 0.6 × APAR + 12, (R² = 0.86; p < 0.001; n = 18) for the upland sown pastures, and ANPP = 0.27 × APAR + 26, (R² = 0.74; p < 0.001; n = 18) for the lowland naturalized pastures, with ANPP in g/m²/60 days and APAR in MJ/m²/60 days. The models were able to predict independent ANPP values with acceptable accuracy. Computational procedures were automated and run in a Relational Data Base Manager System that stored and managed all the information. The system is currently monitoring 212,794 ha in 83 farms and provides monthly ANPP values for the previous month and a history of the last 6 years. The data so generated show ANPP differences between the two major forage resources, considerable variability of a given month’s ANPP among years and paddocks, and contrasting among-farm differences in the efficiency of conversion of ANPP and forage supplements into beef production. The system was well accepted by end users who utilize it mainly for making near real time decisions according to last month ANPP, and explaining results of previous production cycles by incorporating ANPP as an explicative variable. However, there were differences among farmers in the degree of utilization, apparently related to the advisor’s attitude toward this new technology. Our results indicate that (1) forage production of large extensions can be monthly monitored at the paddock level by a small laboratory with capabilities in geographic information systems, and (2) advisors and farmers apply this information to their managerial decisions.  相似文献   

Measuring versus estimating net radiation and soil heat flux: Impact on Penman–Monteith reference ET estimates in semiarid regions     

Pedro Gavilán  Joaquín Berengena  Richard G. Allen 《Agricultural Water Management》2007

The standardized ASCE Penman–Monteith and FAO-56 equations were used to estimate reference evapotranspiration (ET₀) using estimated and measured net radiation (R_n) and soil heat flux (G), based on hourly and daily meteorological data. The estimates were evaluated against lysimeter measurements. The results indicate that using measured or estimated values of R_n and G can have significant effect on the accuracy of the ET₀ estimations, especially when calculations were made on an hourly basis. The FAO-56 version performed very well during the irrigation season on a daily basis. The use of measured R_n and G did not improve ET₀ estimation on a daily basis, therefore, the use of estimated R_n and G appears to be dependable when calculations are based on 24-h weather data. When daily ET₀ was calculated from hourly estimations, the results were different depending on the version used. The ASCE version was more accurate, especially when R_n and G were measured. Therefore, measurement of R_n and G may have potential to improve estimation only when daily ET₀ is calculated from hourly estimations. The PM FAO-56 version was always a little less accurate than the ASCE version. For hourly calculations, using a constant surface resistance (as in FAO-56 version), the PM method underpredicted for high evaporative demand and vice versa. The ASCE version performed better than PM FAO-56 version when R_n and G were measured and estimated. Therefore, ASCE version tended to provide quite accurate values of hourly ET₀, even using estimated values of R_n and G. As conclusion, the methods proposed by FAO-56 for estimating R_n and G tended to produce accurate estimates for daily and hourly ET₀ under semiarid conditions and can be used with some degree of confidence for estimating ET₀. In addition, results suggest that the ASCE standardized equation on an hourly basis improved the accuracy of ET₀ estimation with respect to the FAO-56 version.  相似文献   

SIRIAS: a simulation model for sprinkler irrigation     

P. Carrión  J. Tarjuelo  J. Montero 《Irrigation Science》2001,20(2):73-84

Uniformity of distribution in irrigation systems plays an important role in the optimum use of irrigation water, with direct repercussions on water-use efficiency and production. To evaluate the effects of the wind on sprinkler water uniformity, it is necessary to measure infield water distribution under different wind conditions and then calculate the parameters that define water distribution. This paper perfects the SIRIAS simulation model for sprinkler systems, which can be used to design new irrigation installations or to improve existing ones. Using ballistic theory to simulate the trajectory of drops discharged by the sprinkler, the model obtains wind-distorted water distribution, with a new formulation for the air drag coefficient. It takes into account three options to distribute the evaporation and drift losses in the irrigation process. SIRIAS software has been programmed using Delphi language for Windows 95, 98 and NT.  相似文献   

Multivariate analysis of invasive plant species distributions in southern US forests     

Lázaro-Lobo  Adrián  Ramirez-Reyes  Carlos  Lucardi  Rima D.  Ervin  Gary N. 《Landscape Ecology》2021,36(12):3539-3555

Landscape Ecology - Invasive plants cause significant impacts in forested areas throughout the world. However, little is known about the relative importance of environmental drivers on the...  相似文献   

Glutathione Depletion and Insecticide Synergism in Triatoma infestans produced by the Butyl Ester of Buthionine Sulfoximine     

Hector Masuh  Andrea Fontn  María I. Picollo  Susana A. de Licastro  Eduardo Zerba 《Pest management science》1996,47(2):181-184

The butyl ester of buthionine sulfoximine (BBSO) applied topically to the nymph V stage of Triatoma infestans (Klug) caused glutathione depletion which was maintained for four days after treatment. Topical pre-treatment of nymph V with BBSO significantly synergised the toxicity of DDT and fenitrothion to T. infestans.  相似文献   

Honey as the Potential Natural Source of Cholinesterase Inhibitors in Alzheimer’s Disease     

Baranowska-Wójcik  Ewa  Szwajgier  Dominik  Winiarska-Mieczan  Anna 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):30-32

Plant Foods for Human Nutrition - Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized, among others by abnormal levels of acetyl- and butyrylcholinesterase in...  相似文献   

Exogenous Salicylic Acid Improves Phenolic Content and Antioxidant Activity in Table Grapes     

Blanch  Gracia Patricia  Gómez-Jiménez  Maria C.  del Castillo  Maria Luisa Ruiz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(2):177-183

Plant Foods for Human Nutrition - Grapes contain high contents of phenolics, which are known to possess health promoting properties. Exogenous application of phytoregulators, mainly methyl...  相似文献   

Sorghum Pasta and Noodles: Technological and Nutritional Aspects     

Palavecino  Pablo Martín  Curti  María Isabel  Bustos  Mariela Cecilia  Penci  María Cecilia  Ribotta  Pablo Daniel 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(3):326-336

Plant Foods for Human Nutrition - Sorghum is a major cereal crop with various agronomic advantages, contains health-promoting compounds and is gluten-free. There is a growing tendency to use...  相似文献   

Evaluation of long‐term protection from nursery to vineyard provided by Trichoderma atroviride SC1 against fungal grapevine trunk pathogens     

Mnica Berbegal  Antonio Ramn‐Albalat  Maela Len  Josep Armengol 《Pest management science》2020,76(3):967-977

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