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111.
农业生产基地项目具有影响范围大、产品服务多元化等特点,涉及行业类别较多,其环境影响评价文件也相对复杂。环境影响评价报告编制单位应充分与建设方进行沟通,熟悉项目建设内容,挖掘项目可能的产生污染的环节和设施,明确环境影响范围和环境敏感点,并对项目损益进行两方面的分析。 相似文献
112.
《Soil Use and Management》2018,34(1):72-84
Soya bean [Glycine max (L.) Merr] yields >6719 kg/ha (100 bu/ac) have only recently and infrequently been achieved. Quantifying soil property differences between high‐ and average‐yielding areas can help to further identify non‐plant‐related properties contributing to soya bean yield potential. The objective of this study was to evaluate the effects of region and soil depth on soil property differences between high‐ and average‐yielding areas. In each of the seven regions of the ‘Grow for the Green’ yield contest in Arkansas, prior to or just after harvest in 2014 and 2015, soil samples were collected from the top 20 cm of one contest high‐yield (HY ) area that was in close proximity to an average‐yield (AY ) area. Across all regions and both years, soya bean yields differed (P < 0.05) between yield areas, averaging 4701 and 5498 kg/ha in AY and HY areas, respectively. Averaged across soil depth and years, numerous soil properties differed (P < 0.05) between HY and AY areas within at least one of seven regions. Total soil C content was at least 20.2% greater in the HY than in the AY area in three of seven regions. Extractable soil P content was, on average, 19.4 kg/ha greater in HY than in AY areas in three of the seven regions. Results from this study have the potential to help producers better understand soil properties that contribute to or hinder achieving ultra‐high (>6719 kg/ha) soya bean yields. 相似文献
113.
天然橡胶(顺式-1,4-聚异戊二烯)是一种重要的工业原料,主要来自橡胶树。以天然橡胶的生物合成与产量形成为主要内容的产胶生物学研究为橡胶树高产遗传改良提供理论指导,近10年取得了重要进展。本文从橡胶树基因组测序、橡胶转移酶、转基因、以及转录组和蛋白质组等4个方面介绍产胶生物学研究主要进展,并讨论了相关领域研究存在的问题,对未来5~10年需重点关注的研究内容提出了建议。在介绍橡胶转移酶时,同时概述其他几种产胶植物的相关研究进展。 相似文献
114.
李恩普 《农业科研经济管理》2011,(4):28-31
该文结合中国农科院及其所属研究所党建工作的情况,按照提高党的建设科学化水平的新要求,以科学发展观为指导,深刻理解和正确把握党的建设的科学化内涵,进一步深化对党的建设和执政规律的认识。此外,该文联系实际,分析农科院所党建工作的新特点,找准党建工作着力点,坚持以人为本,加强组织建设,深化创先争优,构建和谐院所,充分发挥党组织的政治核心作用等方面提高党建工作的科学化水平。 相似文献
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基于一种不依赖交通事故和交通冲突数据的事前安全评价方法——安全服务水平评价方法,分析了影响公路平面交叉口安全服务水平的客观因素,建立了设计阶段安全评价模型。结合江苏省临海高等级公路的平交口数据进行实例验证,提出了设计阶段平交口安全评价方案及优化流程,改善效果明显。 相似文献
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119.
André Fischer Sbrissia Daniel Schmitt Paulo Gonçalves Duchini Sila Carneiro Da Silva 《Journal of Agronomy and Crop Science》2020,206(5):630-639
It is well reported in the scientific literature that pastures can have similar net forage accumulation when managed with contrasting structures. However, we hypothesized that the dynamics of forage accumulation in grazed swards is linked to seasonal-environmental conditions. Marandu palisadegrass (Brachiaria brizantha [Hochst. ex A. Rich.] was used as the forage species model. The experimental treatments were four grazing heights (10, 20, 30 and 40 cm) allocated to experimental units according to a randomized complete block design with four replicates and evaluated throughout four contrasting environmental seasons (summer, autumn, winter–early spring and late spring). Under rainy and warm periods, greater net forage accumulation was observed in pastures maintained taller; on the contrary, during the mild and dry periods, net forage accumulation rate reduced as grazing height increased. Such patterns of responses were related to compensations between tiller population density and tissues flows during summer and late spring and the reduced capacity of taller canopies to compensate lower population with greater growth rates during autumn and winter–early spring. Grazed swards changed their patterns of forage growth as they transitioned from favourable to more abiotic stressful conditions, suggesting that seasonal adjustments in grazing intensities are necessary in order to maximize forage production. 相似文献
120.
This study aimed to evaluate the effect of different dose levels of aguamiel (Agave atrovirens) on in vitro cecal gas, methane (CH4), and carbon dioxide (CO2) productions of five forage species (Avena sativa [hay]), Moringa oleifera, Caesalpinia coriacea, Salix babylonica, and Eichhornia crassipes using inocula from the horse. The forage samples were incubated with three doses of aguamiel: 0, 34, and 68 μg of aguamiel/g dry matter (DM) of substrate. Cecal inocula were collected from four adult female Criolla horses (3–4 years of age and weighing 300 ± 15.0 kg) grazed on native grasses for about 8 hours without supplementation. Forage type affected (P < .001) cecal asymptotic, rate and lag time of gas, CH4 and CO2 productions (mL/g DM), pH and DM degradability. Aguamiel dose had linear and quadratic effects (P < .05) on the asymptotic and rate of CH4 productions and rate and lag time of CO2 productions (mL/g DM). Forage type × aguamiel dose interactions were significant (P < .05) for asymptotic, rate and lag time of gas, and CH4 and CO2 productions (mL/g DM). Forage species effects were pronounced (P < .05) on CH4 and CO2 productions (mL/g incubated and degraded DM) and proportional CH4 production at all hours of incubation, except for CO2 production (mL/g incubated DM). Aguamiel dose affected (P < .05) CO2 production (mL/g incubated DM) and proportional CO2 production at the incubated hours. Forage type × aguamiel dose interactions were observed (P < .05) for CO2 production (mL/g incubated DM) and proportional CO2 production at the incubated hours but had no impact on CH4 production. It is concluded that addition of aguamiel to five forage species affected fermentation kinetics of gas production resulting in different in vitro cecal gas, CH4 and CO2 productions from these substrates. 相似文献