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Technical efficiency of cocoa farms at varying elevation levels in davao city, Philippines: implications to sustainable upland farming systems

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Journal of Mountain Science 2024年第1期21卷 33-48页

作者： Francis Levi A.dURANO Jon Marx SARMIENTO Larry N.dIgaL pedro A.ALVIOLA IV School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in davao city, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation

关键词： cocoa farms cobb-douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

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Successful eradication of the European rabbit(Oryctolagus cuniculus)and house mouse(Mus musculus)from the island of Selvagem Grande(Macaronesian archipelago),in the Eastern Atlantic

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Integrative Zoology 2010年第1期5卷 70-83页

作者： Paulo OLIVERA dilia MENEZES Roger TROUT Alan BUcKLE pedro GERALdES JoséJESUS Parque Natural da Madeira Quinta do Bom SucessoCaminho do MeioMadeira Forest Research Alice Holt LodgeFarnhamSurrey School of Biological Sciences The University of ReadingReadingUK University of Madeira Department of BiologyCampus of PenteadaPortugal

The Portuguese island of Selvagem Grande(Great Salvage)in Macaronesia is an important seabird breeding station in the eastern *** populations of cory’s shearwater calonectris diomedea(Scopoli,1769),Bulwer’s petrel Bulweria bulweria(Jardine&Selby,1828)and little shearwater Puffinus assimilis baroli(Bonaparte,1857)are present,and white-faced storm-petrel Pelagodroma marina(Latham,1790)and Madeiran storm-petrel Oceanodroma castro(harcourt,1851)populations are of global *** Grande also provides diverse habitats for an extensive flora,including 11 endemic *** 270-ha island was also inhabited by two alien invasive mammals:the European rabbit Oryctolagus cuniculus(Linnaeus,1758)and the house mouse Mus musculus(Linnaeus,1758).Both are known to have had adverse impacts on breeding seabirds and island *** 2002,the Natural Park of Madeira conducted a program using brodifacoum bait formulations aimed at rabbit and mouse *** 17000 individual baiting points were established on a 12.5×12.5 m *** were also applied by hand“seeding”on steep slopes and cliffs where bait stations could not be *** were removed after a ***,mice persisted for considerably longer and strategic bait applications against them continued for a further six *** assessments by trapping,bait takes and systematic observa-tion of signs over three years,has confirmed the removal of both alien invasive *** paper presents information on these operations,on measures adopted to mitigate adverse impacts of the eradication program on important vertebrate non-target species,including Berthelot’s pipit Anthus berthelotii Bolle,1862 and a species of gecko Tarentola bischoffi Joger,1984 and on the initial response of the island’s ecosystem to the eradication of rabbits and mice.

关键词： alien invasive island restoration Mus musculus non-target mitigation Oryctolagus cuniculus

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Ecophysiology and multivariate analysis for production of Tachigali vulgaris in Brazil:Influence of rainfall seasonality and fertilization

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林业研究:英文版 2023年第5期34卷 1289-1305页

作者： pedro Henrique Oliveira Simoes candido Ferreira de Oliveira Neto Manoel Tavares de Paula dênmora Gomes de Araújo Rodrigo Silva do Vale Joao Olegário Pereira de carvalho Universidade Federal de Mato Grosso Campus Universitario de SinopSinop 78550728Mato GrossoBrazil Universidade Federal Rural da Amazonia Campus BelemBelem 66077830ParaBrazil Universidade do Estado do Para Centro de Ciencias Naturais e TecnologiaBelem 66095015ParaBrazil Universidade Federal Rural da Amazonia Campus Capitao-PocoCapitao Poco 68650000ParaBrazil

Studies on fertilization management of species native to the Amazon for energy plantations contribute to the diversity of species use and reduce biological risk due to the excessive use of clones or hybrids of *** study evaluates the effect of precipitation seasonality and phosphorus and potassium fertilization on gas exchange in a Tachigali vulgaris *** levels of P(zero,65.2,130.4 kg ha^(-1))and three of K(zero,100.0,200.0 kg ha^(-1))were applied in a 3×3 factorial randomized block *** exchange measurements were conducted in April and November *** low rainfall,high irradiance period,photo synthetic rates were up to four times higher than in the high rainfall period,reaching 20.3μmol m^(-2)s^(-1)in the treatment with 130.4 g kg^(-1)of P and 100.0 g kg^(-1)of *** analysis and principal component analysis reduced the initial eight gas exchange variables to two and three principal components in periods of high and low rainfall,*** multivariate method used in this study readily identified variations in the variables as a function of rainfall,with high reliability in explaining the data set.

关键词： Photosynthesis rate Stomatal conductance Principal component analysis Factor analysis Tachigali vulgaris

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Synthesis of Solid Acid catalysts Based on TiO2- SO42-and Pt/TiO2- SO42-Applied in n-Hexane Isomerization

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Open Journal of Metal 2013年第3期3卷 34-44页

作者： Juan Manuel Hernández Enríquez Luz Aracely cortez Lajas Ricardo ga.cía Alamilla Estefanía ángeles San Martín pedro ga.cía.a.a.illa.edwa.d brent ha.dy Guadalupe cárdenas galindo Luz Arcelia ga.cía Serrano cIEP Facultad de Ciencias Químicas Universidad Autónoma de San Luis Potosí Av. Dr. Manuel Nava #6 Zona Universitaria 78210 San Luis Potosí San Luis Potosí México Instituto Politécnico Nacional Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo 30 de Junio #1520 Barrio La Laguna Ticomán 07340 México D.F. México Instituto Tecnológico de cd. Madero División de Estudios de Posgrado e Investigación Juventino Rosas y Jesús Urueta S/N Col. Los Mangos 89440 Cd. Madero Tamaulipas México Universidad Juárez Autónoma de Tabasco División Académica de Ciencias Agropecuarias Avenida Universidad S/N Zona Cultura Colonia Magisterial 86040 Villahermosa Tabasco México

The physicochemical properties and catalytic activity of pure and sulfated titanium oxide (TiO2 and ) is described in this work. Titanium hydroxide synthesized by the sol-gel method was impregnated with a 1 N H2SO4 solution, varying amount of sulfate ions () in the range from 10 to 20 wt%. Pure and modified hydroxides were calcined at 500°c for 3 h and then characterized by Tga-dTG, XRd, BET, FT-IR, potentiometric titration with n-butylamine and 2-propanol dehydration. catalytic activity of materials was tested in the n-hexane isomerization at 350°c. The results showed that TiO2 and mainly developed anatase phase. All have acceptable specific surface area (95-105 m2/g). Potentiometric titration with n-butylamine revealed that showed higher acidity (430-530 mV) than compared to pure TiO2 (﹣15 mV), indicating that this oxide only has weak acidity. The results showed good relationship between acidity determined by potentiometric titration with n-butylamine and the catalytic activity evaluated by 2-propanol dehydration and n-hexane isomerization. Titanium oxide with 20 wt% ofions was the material that demonstrated the highest catalytic activity for both reactions.

关键词： Acid catalysts Sulfated Titanium Oxide Physico-chemical Properties n-Hexane Isomerization

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Unpaved rural roads as source areas of sediment in a watershed of the Brazilian semi-arid region

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International Journal of Sediment Research 2019年第5期34卷 475-485页

作者： Teresa Raquel Lima Farias pedro Henrique Augusto Medeiros Joaquín Navarro-Hevia José carlos de Araújo Federal Institute of Education Science and Technology of Ceará University of Valladolid Campus La Yutera Federal University of ceará Department of Agricultural Engineering Campus do Pici

Approximately 80% of the road network in Brazil is unpaved and shows evidences of a high erosion potential. In the semi-arid caatinga Biome in the northeast of the country, a monitoring programme has been done for two years in order to analyze runoff and sediment production from unpaved rural roadways and from embankments. Sediment production ranged from 0.30 to 0.92 Mg/ha yr, higher than in undisturbed areas, but generally lower than that reported for unpaved roads in other regions. However,this is a semi-arid area with low rainfall and runoff and, hence, with a limited hydrological connectivity and sediment production. Sediment production on an embankment with no vegetation was around ten times higher than on an embankment with vegetation. On the road surface, annual sediment production(normalized for gradient) in a section with traffic was three times higher than for a road surface without traffic. In addition, events that occurred after roadway maintenance activities generated peaks of sediment concentration of over 5000 mg/L. These results suggest that sediment production from roads and embankments with bare surfaces is at least one order of magnitude higher than in undisturbed catchment areas. Maintenance activity and vehicle traffic contribute to an increase in sediment availability and impact on the sediment concentration, but less intensely on sediment loads, which depend on the runoff magnitude of the events occurring after roadway maintenance. It was also found that the natural vegetation of the semi-arid region potentially captures sediment on roadway embankments; thereby playing an important role in breaking connectivity between the sediment flow from unpaved roads and the natural drainage system of the catchment.

关键词： Sediment production caatinga vegetation Road maintenance Embankment

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Evapotranspiration and water-use efficiency of irrigated colored cotton cultivar in semiarid regions

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Agricultural Sciences 2012年第5期3卷 714-722页

作者： pedro V.de Azevedo José R.c.Bezerra Vicente de P.R.da Silva Federal University of campina Grande Campina GrandeBrazil Brazilian company for Agriculture and Animal Research(Embrapa Algodão) Campina GrandeBrazil

Irrigation studies provide a framework for evaluating agricultural production and the water resource management in locations where water is scarce. Field experiments were conducted at Barbalha- cE (northwestern Brazil) during 2004 and 2005 cropping seasons to investigate the effects of different irrigation water depths on the water-use efficiency and yield of the BRS 200-brown cotton cultivar (Gossypium hirsutum L.). Three irrigation treatments were applied: T1 = 80%;T2 = 100% and T3 = 120% of the potential evapotranspiration (ETp). The Bowen ratio-energy balance was used to obtain crop evapotrnaspiration (ETc) while daily reference evapo-transpiration (ETo) was obtained by the Penman-Monteith approach. Irrigation water was applied by a sprinkler system during both cropping seasons. The daily evapotranspiration ranged from 2.59 mm·day-1 at the emergence to 5.89 mm·day-1 at first square growth stage with an accumulated value of 528.7 mm as a mean of the two cropping seasons. The average crop coefficient across both years (2004-2005) was 0.90, with minimum and maximum values of 0.46 and 1.17 at emergency and first flower growth stages, respectively. The results also showed that the increase in irrigation from 80% to 120% of ETp resulted in a significant increase in the seed-cotton yield (from 2476.0 to 3289.5 kg·ha-1), while lint percentage and water-use efficiency (WUE) were slightly reduced from 35.7% to 35.6% and from 0.60 to 0.53 kg·m-3, respectively. These results suggests that the cotton crop (cultivar BRS-200 brown) reaches higher water-use efficiency when irrigated with 80% of the crop evapotrnaspiration obtained as a function of the reference evapotranspiration and the crop coefficient proposed by FAO. However, the maximum seed-cotton yield is obtained when irrigated with 120% of that crop evapotranspiration.

关键词： Bowen Ratio crop Evapotranspiration Irrigation Treatments Seed-cotton Yield

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Potential Use of a Poultry Manure digestate as a Biofertiliser:Evaluation of Soil Properties and Lactuca sativa Growth

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Pedosphere 2019年第1期29卷 60-69页

作者： Natalia MóRTOLA Romina ROMANIUK Vanina cOSENTINO Maximiliano EIZA Patricia cARFAGNO pedro RIZZO Patricia BRES Nicolás RIERA Marcos ROBA Mariano BUTTI daiana SAINZ Lucrecia BRUTTI Soil Institute National Institute of Agricultural Technology (INTA) Institute of Zoology and Agricultural Microbiology National Institute of Agricultural Technology (INTA) Rural Engineering Institute National Institute of Agricultural Technology (INTA)

Anaerobic digestion is a process that is widely used for the treatment of organic wastes. The digestate can be used as a soil amendment or crop fertiliser. The aims of our work were to evaluate 1) the physicochemical composition and pathogen content in a digestate from poultry manure, according to international regulations, and 2) the effect of its soil application on the major chemical and biological soil properties and on the growth of Lactuca sativa. The experiment consisted of two groups of pots(with and without crop). Treatments applied to each group were as follows: low and high doses of digestate and inorganic fertiliser, and no application(control)(low dose: 70 kg nitrogen(N) ha^(-1) and 21 kg phosphorus(P) ha^(-1); high dose: 210 kg N ha^(-1) and 63 kg P ha^(-1)). Soil samples were taken 7 and 34 d(harvest) after treatment applications. Heavy metal and pathogen contents in the digestate were below the upper limit values. despite the high pH and electrical conductivity values of the digestate, both soil parameters presented acceptable values for crop growth. Although there were no initial increases in total inorganic N and available P in soil with digestate application, an increase in the fresh weight of crop was observed with the high dose application. This is probably associated with the slow nutrient release from the digestate during the development of the crop. changes in the microbial community were temporary and occurred at the initial sampling stage of the experiment.

关键词： anaerobic digestion crop yield organic fertiliser organic waste soil amendment soil chemical properties soil microbiological properties

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Interaction between Soybean cultivars and Seed density

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American Journal of Plant Sciences 2015年第9期6卷 1425-1434页

作者： Igor Oliveri Soares pedro Milanez de Rezende Adriano Teodoro Bruzi Alan Mario Zuffo Everton Vinicius Zambiazzi Vanoli Fronza cícero Monti Teixeira department of Agriculture Federal University of Lavras (UFLA) Lavras Brazil Brazilian Agricultural Research corporation (Embrapa-Soja) Londrina Brazil Agricultural Research company of Minas Gerais (Epamig) Uberaba Brazil

Plant, environmental conditions and management type will determine final crop yield. Enhanced yield can be reached by using well-adapted and potentially productive genotypes;all of them ally to crop cultural practices and management. Among these, seed density stands out, once it interferes with plant morphology and competition for water and nutrients. Thus, this study aimed to evaluate the effect of varied seed densities on agronomic traits in soybean, besides identifying cultivars with wide adaptability to different environments and seed densities. Six soybean cultivars were assessed under four seed densities (100, 200, 300 and 400 thousand plants·ha-1), in nine different environments from Minas Gerais State, Brazil. The experimental design was a completely randomized block design with three replications. The BRSMG 760SRR and BRSMG 820RR cultivars had the best average performance independent of the environments and seed densities. The seed density of 300 thousand plants per hectare showed to be as the most adequate for soybean cultivation on the evaluated environments. Furthermore, seed density interacted with the agronomic traits in soybean.

关键词： Glycine max L. Merrill Genotypes Yield Plant Population

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Ar/N2/cH4 Glow discharge at Low Pressures

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Journal of Physical Science and Application 2012年第8期2卷 283-288页

作者： Leomar Salazar-Flores Horacio Martinez-Valencia Alfonso Guerrero-Tapia pedro Guillermo Reyes-Romero Posgrado en ciencias Fisicas Universidad Nacional Autonoma de Mexico Avenida Universidad 1000 05000 Mdxico D.F. Mexico Instituto de ciencias Fisieas Universidad Nacional Autonoma de Mexico Apartado postal 48-3 62251 Cuernavaca Morelos Mexico Estudiante del Posgrado de la Facultad de ciencias Universidad Autonoma del Estado de Mexico Instituto Literario 100 Centro 50000 Toluca Estado de Mexico Mexico Facultad de ciencias Universidad Autonoma del Estado de Mexico Instituto Literario 100 Centro 50000 Toluca Estado de Mexieo Mexico

Ar/N2/cH4 glow discharge at low-pressure are studied in a closed system. The plasma was produced in 79.6% N2-15.4% Ar- 5.0% cH4 ternary mixture at pressures between 0.5 and 10.0 Torr. The diagnostic has been made by optical emission spectroscopy （OES）. The principal species observed were： N2, N2＋, cH＋, cN, c2, c3, HI3, ha, c＋ and At. It presents the behaviour of the bands and lines intensities as a function of the pressure. Also, it displays the ratios of intensities of N＋2 （391.44 nm）, cN （392.08 nm）, and H （486.13 nm） to that of the N2 （337.13 rim） as function of pressure. The ratios show a slow decreasing behavior as a function of the pressure. Being the cH/N2 ratio more highest and H/N2 ratio the lowest one. The variations of excited species at different pressures may change the subsequent chemical reactions in the gas phase significantly. The present results suggest that the ion-molecule and molecule-molecule reactions in the gas phase are likely to play a dominant role in the present pressures.

关键词： Glow discharge optical emission spectroscopy low pressure discharge titan's atmosphere.

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Residual Effects of the Organic Amendments Poultry Litter,Farmyard Manure and Biochar on Soybean crop

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Agricultural Sciences 2014年第14期5卷 1376-1383页

作者： Alexandre Martins Abdao dos Passos pedro Milanez de Rezende Everson Reis carvalho Andreia Marcilane Aker EMBRAPA Rondonia Porto VelhoBrazil Federal University of Lavras(UFLA) LavrasBrazil Federal University of Rondonia(UNIR) Rolim de MouraBrazil

The use of organic wastes, as an alternative to inorganic fertilizer, can be an important strategy for Brazilian and tropical agriculture. despite the importance, few field studies have been done for evaluating organic amendments on soybean crops in Brazil. The study aimed to evaluate the residual effects of the organic amendments poultry litter, farmyard manure and biochar combined with mineral fertilizer on some agronomic attributes of a soybean crop. A field experiment was carried out in a split-split-plot scheme, with three replicates in a randomized block experimental design. The organic sources (plots) at rates of 0, 3, 6 and 9 Mg·ha-1 (subplots) combined with 0, 100, 200, 300 and 400 kg·ha-1 (sub subplots) of a mineral fertilizer were applied in 2008. In 2009, only the mineral fertilizer was used on the soybean crop. As a?result, all evaluated attributes were influenced by the treatments, except for the number of grains per pod. The application of poultry litter provided the highest yield (3715 kg·ha-1 using 9 Mg·ha-1 of the source). A synergistic effect between organic amendments and mineral fertilizer was observed. It was found the possibility of decrease doses of mineral fertilizers by prior use of organic amendments. The most effective dose combination application is 5.5 Mg·ha-1 of organic amendments associated with 200 kg·ha-1 of mineral fertilizer to provide optimum yield. The use of organic amendments, rich in nutrients, is a technology to sustainably increase the soybean grain yield.

关键词： Glycine max Integrated Production Organic Wastes Sustainability Yield

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