J. Handelsman, E. Stabb
Hasil untuk "Agriculture (General)"
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E. Bignal, D. McCracken
Qiong Yue, P. Guo
Abstract Water, energy, food, and environment are highly interconnected, with intricate dependencies and multiple uncertainties involved in agricultural system. This paper presents a novel water-energy-food-environment nexus (WEFEN) optimization model for sustainable development of agriculture. The developed model incorporates stochastic multi-objective programming, triangular fuzzy numbers, fuzzy credibility-constrained programming, mixed-integer programming, non-linear programming, and Stewart model into a general optimization framework. The model is capable of (1) balancing the tradeoffs among socio-economic, resources, and environmental concerns; (2) generating valid WEFEN management solutions achieving the targets of maximum net economic benefit, maximum renewable energy production, minimum water footprint, and minimum carbon footprint simultaneously; (3) dealing with complexities and uncertainties existed in agricultural WEFEN systems. The model was applied to the Zhanghe irrigation district to give policy-makers insights into what efforts should be made towards sustainable agricultural management. Flexible alternatives were generated under different scenarios and sensitivity analyses were conducted. Results highlighted the significance of improvement of internal water storage capacity, reasonable farmland management, and compromise decision preferences. The proposed methodology is applicable for other agriculture-centered regions suffering from multifold resources and environment crisis.
L. Garibaldi, M. Aizen, A. Klein et al.
L. D. Quin
Renan Souza, M. A. Rouf Mian, Justin N. Vaughn et al.
Soybean meal is a major component of livestock feed due to its high content and quality of protein. Understanding the genetic control of protein is essential to develop new cultivars with improved meal protein. Previously, a genomic region on chromosome 20 significantly associated with elevated protein content was identified in the cultivar Danbaekkong. The present research aimed to introgress the Danbaekkong high-protein allele into elite lines with different genetic backgrounds by developing and deploying robust DNA markers. A multiparent population consisting of 10 F5-derived populations with a total of 1,115 recombinant inbred lines (RILs) was developed using “Benning HP” as the donor parent of the Danbaekkong high-protein allele. A new functional marker targeting the 321-bp insertion in the gene Glyma.20g085100 was developed and used to track the Danbaekkong high-protein allele across the different populations and enable assessment of its effect and stability. Across all populations, the high-protein allele consistently increased the content, with an increase of 3.3% in seed protein. A total of 103 RILs were selected from the multiparent population for yield testing in five environments to assess the impact of the high-protein allele on yield and to enable the selection of new breeding lines with high protein and high yield. The results indicated that the high-protein allele impacts yield negatively in general; however, it is possible to select high-yielding lines with high protein content. An analysis of inheritance of the Chr 20 high-protein allele in Danbaekkong indicated that it originated from a Glycine soja line (PI 163453) and is the same as other G. soja lines studied. A survey of the distribution of the allele across 79 G. soja accessions and 35 Glycine max ancestors of North American soybean cultivars showed that the high-protein allele is present in all G. soja lines evaluated but not in any of the 35 North American soybean ancestors. These results demonstrate that G. soja accessions are a valuable source of favorable alleles for improvement of protein composition.
LI Yexin, LYU Gang, WANG Daohan et al.
【Objective】 Restoring coal mining waste dumps is a way to alleviate their detrimental impact on environment. In this paper, we present the results of an experimental study on distribution and stability of soil aggregates in a reclaimed coal mining overburden dump. 【Method】 The experiment was carried out at a reclaimed coal mine dump site in a grassland region in northern China. We measured the development of fissures from Zone I (GF) to Zone three (GFIII) in the fissure zone. The composition and distribution soil aggregates in these zones were determined using dry-wet sieve method. Aggregate stability and its relationship with the fissures was analyzed. 【Result】 The content of the >0.25 mm air-dried aggregates over the fissure zones was 23.02%~42.70%, and content of the >0.25 mm water-stable soil aggregates was 16.9%~29.52%. There was no significant difference between air-dried aggregates and water-stable aggregates. The content of the >0.25 mm water-stable soil aggregates in the 0~60 cm soil layer in GF, GFⅡ and GF Ⅲ was 25.26%, 26.57%, 23.62%, respectively, while the percentage of aggregate destruction in the three fissure zones was 20.77%~36.17%, 20.52%~25.00%, and 26.58%~40.56%, respectively. The percentage of aggregate destruction in 0~10, 10~20, 20~30, 30~40, 40~50, and 50~60 cm soil layers was 28.81%, 29.96%, 26.19%, 23.50%, 24.91%, and 29.38%, respectively. The fractal dimension of air-dried and water-stable soil aggregates was 2.847~2.919 and 2.898~2.942, respectively. Small aggregates and fine particles are the dominant aggregates. The mean mass diameter (MWD) and geometric mean diameter (GMD) of the air-dried aggregates in three fissure zones were 1.11, 1.05, 1.28 mm, and 0.45, 0.44, 0.49 mm, respectively. The MWD and GMD of water-stable soil aggregates in the three fissure zones were 0.67, 0.73, 0.72 mm, and 0.36, 0.38, 0.37 mm, respectively. Soil in GFⅡ had good structure and aggregate stability. Most of water-stable soil aggregates in the fissure zones were unstable due to the formation and development of fissures. 【Conclusion】 The formation and development of fissures in the reclaimed coal mining overburden dump reduced the stability of soil aggregates, thereby resulting in aggregate segmentation. The larger and wider the fissures were, the less stable the soil aggregates were.
J. Pan, J. Plant, Nikolaos (Nick) Voulvoulis et al.
Daniel Hellerstein
The United States Department of Agriculture’s Conservation Reserve Program (CRP) has evolved from near open enrollment, to competitive enrollment, and now to a mixture of competitive and targeted enrollment. This paper reviews the history of the CRP and the evolution of its enrollment mechanism. I discuss the use of bid caps and the Environmental Benefits Index bid ranking mechanism in the “general” CRP; and the use of highly targeted, but non-competitive, “continuous” CRP. Possible challenges of these designs are discussed, and alternative auction mechanisms are considered that could be more cost effective.
M. Abad, P. Noguera, S. Burés
Xanthoula Eirini Pantazi, Dimitrios Moshou, Dionysis Bochtis
Luiz Cobiniano de Melo Filho, Ivanildo Guilherme Henrique, Orivaldo Arf et al.
O feijoeiro é uma planta exigente em nutrientes, com alta demanda por nitrogênio (N). A fixação biológica de N (FBN) é, provavelmente, a melhor solução para atender essa demanda, especialmente considerando as perdas no sistema solo-planta-atmosfera. O molibdênio (Mo), presente nas enzimas nitrogenase e redutase do nitrato, é fundamental no metabolismo do N, inclusive da FBN. Com objetivo de avaliar se a inoculação das sementes de feijão com Azospirillum brasilense, Rhizobium tropici, e possíveis interações com a adubação nitrogenada e molíbdica em cobertura tem efeito no desenvolvimento e na produtividade do feijoeiro, foi conduzida esta pesquisa. Utilizou-se delineamento experimental de blocos casualizados, em um esquema fatorial 4x2x2. Avaliou-se população de plantas, componentes de produção e produtividade de grãos, em dois cultivos (2017 e 2018). A inoculação das sementes, com A. brasilense, quando associada com 30 kg ha-1 de N em cobertura, incrementa a população de plantas, o número de vagens por planta e o rendimento de grãos. A adubação nitrogenada em cobertura é determinante no aumento de produtividade do feijão de inverno, independente da inoculação ou aplicação de Mo foliar.
M. Khamseh Mahabadi, M. Shirvani, M. R. Mosaddeghi
Shortage of water resources and deterioration of water quality have urged the need to develop new technologies for the removal of contaminants from water. Heavy metals produced by municipal and industrial activities are among the most toxic contaminants present in the natural and waste waters. Different methods have been developed for the elimination of heavy metals from water resources and industrial waste waters. Adsorption is an effective and economic method for the water purification purposes. Nowadays, clays and natural polymers have been widely used as the adsorbents for heavy metals, due to their eco-friendly nature, natural abundance, low cost and high specific surface area. If these adsorbents are used as a hybrid material, some of their physical and chemical restrictions would be alleviated. In this study, polyacrylic acid–bentonite hybrids and natural bentonite were compared in terms of Pb adsorption in the batch and fixed-bed column systems. Besides, the effect of pH on Pb retention was investigated in both systems. The results of the batch studies showed that Langmuir and Freundlich isotherm models were appropriate in ing quilibrium Pb sorption data. Pb sorption by the sorbents was increased with the rise in solution of pH from 4 to 6, showing the greatest Pb sorption capacity at pH values of 4 (83.29 mg g-1) and 6 (103.3 mg g-1). Different indices of filtration and adsorption, including average relative effluent concentration, relative adsorption index, relative transmitted index, and filtration coefficient, were calculated from the break-through curves, indicating that the polyacrylic acid-bentonite nanocomposite was superior in the Pb sorbtion, as compared to bentonite. Also, a higher pH value resulted in the greater Pb removal from the solutions.
Zaman Subhi Madlool, Satar Abood Faris, Ali M. Hussein
The present study was designed to know the effect of sertraline and fluoxetine on the reproductive abilities of male rats. The experiment consisted of five groups (each group contains of 5 males), the first (control) group was injected (I.P) with 0.25ml of normal saline, the second group was injected with sertraline (10 mg / kg), the third group was injected with sertraline (20 mg / kg), the fourth group was injected with fluoxetine (5 mg / kg) and the fifth group was injected with fluoxetine (10 mg / kg). .The results showed a significant decrease (P?0.05) in the number of sperms and in the level of testosterone hormone and a significant increase (P?0.05) in the percentage of sperm deformities in all treated groups when compared with control group. The histologically examination showed that there was changes in the testis including the dissociation of the connective tissue in second and fifth groups, decrease in the number of spermatgonia, and Leydig cells, bloody congestion in third and fifth groups, hemorrhage and necrosis in forth group.
R. Ibidhi, H. Ben Salem
Water scarcity is among the main challenges making vulnerable the livestock farming systems in drylands. The water footprint (WF) indicator was proposed as a metric to measure the impacts of livestock production on freshwater resources. Therefore, this study aimed to assess water use in five different Tunisian sheep production systems using the Water Footprint Network methodology. The primary data were obtained from 1050 sheep farms located in 13 Tunisian provinces. A multivariate analysis was performed to characterize the different farming systems. A validation step of the WF modeled values of sheep meat was conducted in 12 sheep farms belonging to two different farming systems. This was done through year-round monitoring of on-farm practices using water metres and recording equipment’s taking into account the direct and indirect water use. The typology analysis came up with five sheep farming systems that are the mixed sheep-cereal (MSC), the agro-sylvo-pastoral (ASP), the agro-pastoral (AP), the extensive agro-pastoral (EAP) and the mixed sheep-olive tree farming systems. The WF of sheep meat produced under the target farming systems ranged from 8654 to 13 056 l/kg live weight. The evaluation of WF of five different sheep production systems figured out that sheep raised under the EAP farming system had the greatest WF per ton of live animal. However, the ASP farming system exhibited the lowest WF. Water used to grow feedstuffs for sheep production accounts for 98% of the total WF of sheep. The green WF accounts for more than 92% of the total WF in all farming systems. Results of monitoring water use at farm scale show that the modeled values of WF are overestimated by an average of 23.3% and 24.1% for the selected farms assigned to the MSC and AP farming systems, respectively. Water use for sheep production is high in most of the Tunisian farms. Therefore, the general assumption that ‘meat production is a driver of water scarcity’ is supported and should be considered as an important focal point in agricultural and water policies. Particular attention should be given to forage crops with low WFs and high contribution to dry matter to provide ration with low WF. The efficient use of green water along the meat value chain is essential to minimize the depletion of blue water resources and to reduce the economic dependency on virtual water through the import of feedstuffs.
LALIT GOEL, Vijay Shankar, R. K. Sharma
Purpose Mulching is a practice recommended for soil moisture conservation in potato. The wheat straw and rice straw obtained as major crop residues were used as mulching materials to compare their effectiveness for soil moisture retention in potato crop. Methods The field experiments were conducted in a randomized complete block design replicated thrice with three treatments viz. plots incorporated with wheat straw mulch, rice straw mulch at the rate of 10 tons per hectare each and no mulch serving as control. The soil moisture was determined using a soil moisture probe and data were recorded daily at 10 cm, 20 cm and 30 cm soil depths. The Field Emission Scanning Electron Microscopy was used to investigate moisture retention characteristics of the mulch materials. Results Soil moisture retention varied as wheat straw mulch>rice straw mulch>no mulch at 10 cm, 20 cm and 30 cm soil depths, respectively. Highest moisture retention in wheat straw mulch at 10 cm depth is attributed to better moisture absorption ability of wheat straw in comparison to rice straw. Field Emission Scanning Electron Microscope images indicated the presence of smaller sized micro tubes in wheat straw than rice straw, which resulted in more water retention, thereby substantiating the findings of the study. Conclusion Wheat straw mulch is more effective than rice straw mulch for shallow rooted crops like potato, due to better moisture absorption and retention in upper soil layer.
Suzana Kristek, Lidija Lenar, Jurica Jović et al.
The aim of this study was to investigate the possibility to reduce the application of mineral nitrogen fertilizers through the application of beneficial microorganisms (genus Bradyrhizobium, Azotobacter, bacteria Pseudomonas fluorescens, Bacillus spp., etc.). Research was conducted during 2013 and 2014 on Eutric brown soil. The experiment was set up in a split-block scheme with 12 different variants in 4 repetitions: two soybean cultivars were used; two different treatments of nitrogen fertilizers and three different treatments of microbiological preparation were applied. Analysed parameters were soybean grain yield (kg/ha) based on 13% moisture, protein content (%), oil content (%) and hectolitre mass (kg). Given that the climatic conditions in the second year of research were more favourable than in the first year of research, all the elements of research, including control variants, achieved better results in the second year of research. All variants treated with microbiological preparations, either by application in soil or by application in soil combined with foliar treatments, also achieved statistically significant differences compared to the control variants.
L. C. Gray
Alexis Lamz Piedra, Regla M. Cárdenas Travieso, Rodobaldo Ortiz Pérez et al.
Entre los principales factores que afectan la producción de frijol se encuentra la mala distribución de variedades para las diversas condiciones ambientales en que se cultiva. El objetivo de este trabajo fue evaluar el comportamiento agro-morfológico, considerando la caracterización de la variabilidad de líneas de frijol común promisorias para siembras tardías. La siembra se realizó el 20 de enero de 2014 con un diseño de bloques al azar y cuatro repeticiones en la finca “El Mulato”, perteneciente a la Cooperativa de Créditos y Servicios Fortalecida (CCSF) “Orlando Cuellar”, en el municipio San José de las Lajas, Mayabeque. La evaluación se realizó usando 14 variables agro-morfológicos que incluyeron parámetros fenológicos, morfológicos, rendimiento y sus componentes, y resistencia a la roya (Uromyces appendiculatus). Los resultados del análisis de parámetros estadísticos y componentes principales, permitió detectar la variabilidad genética entre las líneas evaluadas. Además, se detectó que las variables de mayor correlación con el rendimiento fueron el número de vainas por plantas y la masa de 100 granos. De forma general, seis de las líneas evaluadas combinan alto potencial de rendimiento y reacción entre intermedia y altamente resistente ante la roya, destacándose la línea SCR 15, con rendimiento potencial muy superior a los reportados en Cuba hasta la fecha. Esto sugiere evaluar estas líneas en ensayos regionales para una posterior generalización-extensión de los posibles cultivares que contribuyan a enfocar un manejo adecuado de estos genotipos y su empleo como fuentes de resistencia a la roya en los programas de mejoramiento genético del frijol.
J. Igual, A. Valverde, E. Cervantes et al.
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