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Production Goals (production + goal)
Selected AbstractsBiodiversity in tropical agroforests and the ecological role of ants and ant diversity in predatory functionECOLOGICAL ENTOMOLOGY, Issue 4 2006STACY M. PHILPOTT Abstract 1.,Intensive agricultural practices drive biodiversity loss with potentially drastic consequences for ecosystem services. To advance conservation and production goals, agricultural practices should be compatible with biodiversity. Traditional or less intensive systems (i.e. with fewer agrochemicals, less mechanisation, more crop species) such as shaded coffee and cacao agroforests are highlighted for their ability to provide a refuge for biodiversity and may also enhance certain ecosystem functions (i.e. predation). 2.,Ants are an important predator group in tropical agroforestry systems. Generally, ant biodiversity declines with coffee and cacao intensification yet the literature lacks a summary of the known mechanisms for ant declines and how this diversity loss may affect the role of ants as predators. 3.,Here, how shaded coffee and cacao agroforestry systems protect biodiversity and may preserve related ecosystem functions is discussed in the context of ants as predators. Specifically, the relationships between biodiversity and predation, links between agriculture and conservation, patterns and mechanisms for ant diversity loss with agricultural intensification, importance of ants as control agents of pests and fungal diseases, and whether ant diversity may influence the functional role of ants as predators are addressed. Furthermore, because of the importance of homopteran-tending by ants in the ecological and agricultural literature, as well as to the success of ants as predators, the costs and benefits of promoting ants in agroforests are discussed. 4.,Especially where the diversity of ants and other predators is high, as in traditional agroforestry systems, both agroecosystem function and conservation goals will be advanced by biodiversity protection. [source] Regional water resource implications of bioethanol production in the Southeastern United StatesGLOBAL CHANGE BIOLOGY, Issue 9 2009JASON M. EVANS Abstract The Energy Independence and Security Act (EISA) of 2007 mandates US production of 136 billion L of biofuel by 2022. This target implies an appropriation of regional primary production for dedicated feedstocks at scales that may dramatically affect water supply, exacerbate existing water quality challenges, and force undesirable environmental resource trade offs. Using a comparative life cycle approach, we assess energy balances and water resource implications for four dedicated ethanol feedstocks , corn, sugarcane, sweet sorghum, and southern pine , in two southeastern states, Florida and Georgia, which are a presumed epicenter for future biofuel production. Net energy benefit ratios for ethanol and coproducts range were 1.26 for corn, 1.94 for sweet sorghum, 2.51 for sugarcane, and 2.97 for southern pine. Corn also has high nitrogen (N) and water demand (11.2 kg GJnet,1 and 188 m3 GJnet,1, respectively) compared with other feedstocks, making it a poor choice for regional ethanol production. Southern pine, in contrast, has relatively low N demand (0.4 kg GJnet,1) and negligible irrigation needs. However, it has comparatively low gross productivity, which results in large land area per unit ethanol production (208 m2 GJnet,1), and, by association, substantial indirect and incremental water use (51 m3 GJnet,1). Ultimately, all four feedstocks require substantial land (10.1, 3.1, 2.5, and 6.1 million ha for corn, sugarcane, sweet sorghum, and pine, respectively), annual N fertilization (3230, 574, 396, 109 million kg N) and annual total water (54 400, 20 840, 8840, and 14 970 million m3) resources when scaled up to meet EISA renewable fuel standards production goals. This production would, in turn, offset only 17.5% of regional gasoline consumption on a gross basis, and substantially less when evaluated on a net basis. Utilization of existing waste biomass sources may ameliorate these effects, but does not obviate the need for dedicated primary feedstock production. Careful scrutiny of environmental trade-offs is necessary before embracing aggressive ethanol production mandates. [source] Stearoyl CoA desaturase (SCD) gene polymorphisms in Italian cattle breedsJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 1 2008E. Milanesi Summary Stearoyl CoA desaturase (SCD) is the key enzyme involved in the endogenous synthesis of conjugated linoleic acid (CLA) in ruminants. Changes in the enzymatic activity as a result of SCD gene polymorphism and regulation have been hypothesized to cause diet-independent variations of CLA content in milk. Evidences for the direct influence of SCD polymorphism on fatty acid composition of milk and beef have also been reported. To evaluate genetic differences because of breed and/or selection goal, we investigated the polymorphism of three previously reported single nucleotide polymorphisms located in exon 5 of the SCD gene in 11 cattle breeds raised in Italy and selected for different production goals. Results obtained: (i) evidenced a high variability in the allele frequencies across breeds; (ii) detected three novel haplotypes, one of which is private to indigenous beef breeds, and (iii) showed a significant association between haplotypes and selective goal. [source] Genetic characterization of specific pathogen-free rhesus macaque (Macaca mulatta) populations at the California National Primate Research Center (CNPRC)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 7 2010Sree Kanthaswamy Abstract A study based on 14 STRs was conducted to understand intergenerational genetic changes that have occurred within the California National Primate Research Center's (CNPRC) regular specific pathogen-free (SPF) and super-SPF captive rhesus macaque populations relative to their conventional founders. Intergenerational genetic drift has caused age cohorts of each study population, especially within the conventional population, to become increasingly differentiated from each other and from their founders. Although there is still only minimal stratification between the conventional population and either of the two SPF populations, separate derivation of the regular and super-SPF animals from their conventional founders has caused the two SPF populations to remain marginally different from each other. The regular SPF and, especially, the super-SPF populations have been influenced by the effects of differential ancestry, sampling, and lost rare alleles, causing a substantial degree of genetic divergence between these subpopulations. The country of origin of founders is the principal determinant of the MHC haplotype composition of the SPF stocks at the CNPRC. Selection of SPF colony breeders bearing desired genotypes of Mamu-A*01 or -B*01 has not affected the overall genetic heterogeneity of the conventional and the SPF research stocks. Because misclassifying the ancestry of research stocks can undermine experimental outcomes by excluding animals with regional-specific genotypes or phenotypes of importance, understanding founder/descendent genetic relationships is crucial for investigating candidate genes with distinct geographic origins. Together with demographic management, population genetic assessments of SPF colonies can curtail excessive phenotypic variation among the study stocks and facilitate successful production goals. Am. J. Primatol. 72:587,599, 2010. © 2010 Wiley-Liss, Inc. [source] | ||||||||||