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71.
探索庐江地区不同栽培方式对油菜产量与经济效益的影响,在相同茬口条件下,以陕油28为试验材料,研究人工育苗移栽、机条播和无人机飞播等三种栽培方式对油菜生育特性、产量构成及经济效益等影响。结果表明,人工移栽产量最高,机条播经济效益最好,亦是目前农户主要栽培方式。作为规模生产主体,由于劳动力等因素,选择机条播为最佳。  相似文献   
72.
李波 《蔬菜》2021,(10):57-60
为了解决高寒及长江流域以南多雨地区土墙温室难建问题及实现温室育种、种植自动化、机械化作业,研发了一种新型装配式冬暖式C919温室,温室通过组装完成,采用钢制螺旋桩,不用焊接,只需在地下打螺旋桩,即可实现全天候施工。温室采用五防设计(防台风、防雨、防雪、防低温、防高温),具有土地利用率高(75%左右)、建设周期短(千亩园区建设周期90 d)、设计寿命长(50年)、材料环保(采用宝钢BFS 600高强不锈钢)、建设成本使用周期费用摊销低(土墙温室的70%)、运营维护成本低(土墙温室的50%)、机械作业用工少(减少人工60%以上)等优点,填补了高寒(-40 ℃以内)及长江流域以南多雨地区大跨度、装配式、全日光能源温室的空白。  相似文献   
73.
以‘克新1号’马铃薯为试验材料,试验设置低、中、高3个施肥量处理,在复合肥和有机肥的基础上,每个处理中固体胶冻样类芽孢杆菌微生物菌剂设置4个不同的梯度处理,在马铃薯块茎膨大期冲施定量的液体胶冻样类芽孢杆菌微生物菌剂,探究增施胶冻样类芽孢杆菌微生物菌剂对马铃薯生长指标、产量、品质及经济效益等的影响,旨在找出适合蒲县当地的科学施肥方法,为其马铃薯的高产优质生产提供理论和生产实践依据。结果表明,适量增施微生物菌剂有利于提高马铃薯产量、品质和经济效益等指标,但高浓度的微生物菌剂却抑制马铃薯的生长,在本试验中以低肥量处理下的T2组效果最佳,其株高、出苗率、维生素C含量、产量及净利润比常规施肥组分别提高了6.83%、5.31%、92.11%、27.0%和16.94%,还原糖含量降低了18.42%,是高产优质马铃薯的科学施肥配方及标准化生产技术方案。  相似文献   
74.
Composting and thermal drying are amongst the most commonly used post-digestion processes for allowing sanitation and biological stabilization of sewage sludge from municipal treatment plants, and making it suitable as soil conditioner for use in agriculture. To assess the impact of sludge-derived materials on soil microbial properties, fresh (LAF), composted (LAC) and thermally dried (LAT) sludge fractions, each resulting from a different post-treatment process of a same aerobically digested sewage sludge, were added at 1% (w/w) application rate on two contrasting (a loam and a loamy sand) soils and incubated under laboratory conditions for 28 days. Soil respiration, microbial ATP content, hydrolytic activities and arginine ammonification rate were monitored throughout the incubation period. Results showed that soil biochemical variables, including the metabolic quotient (qCO2), were markedly stimulated after sludge application, and the magnitude of this stimulatory effect was dependent on sludge type (precisely LAT > LAF > LAC), but not on soil type. This effect was related to the content of stable organic matter, which was lower in LAT. Genetic fingerprinting by PCR–DGGE revealed that compositional shifts of soil bacterial and, at greater extent, actinobacterial communities were responsive to the amendment with a differing sludge fraction. The observed time-dependent changes in the DGGE profiles of amended soils reflected the microbial turnover dependent on the sludge nutrient input, whereas no indications of adverse effects of sludge-borne contaminants were noted. Our findings indicate that composting rather thermal drying can represent a more appropriate post-digestion process to make sewage sludge suitable for use as soil conditioner in agriculture.  相似文献   
75.
李晨燕 《安徽农业科学》2015,(5):159-160,184
通过分析有林地生产力与立地条件和林分结构中各因子的关系,探索制约有林地生产力的主要因素.结果表明:不同立地质量中Ⅰ类地单位蓄积量最高(268.86±20.24 m3/hm2),不同坡向中东坡单位蓄积量最高(269.78±38.54 m3/hm2),不同树种组成中10杉类型单位蓄积量最高(259.33±14.62 m3/hm2);有林地生产力与林分年龄、林分密度正相关,相关系数R分别为0.590、0.460;有林地生产力与海拔、坡度相关性不显著.以上结果说明立地质量、坡向和树种组成对有林地生产力影响显著;有林地生产力与林分年龄、林分密度相关,与海拔、坡度无关.  相似文献   
76.
Many crop growth models require daily meteorological data. Consequently, model simulations can be obtained only at a limited number of locations, i.e. at weather stations with long-term records of daily data. To estimate the potential crop production at country level, we present in this study a geostatistical approach for spatial interpolation and aggregation of crop growth model outputs. As case study, we interpolated, simulated and aggregated crop growth model outputs of sorghum and millet in West-Africa. We used crop growth model outputs to calibrate a linear regression model using environmental covariates as predictors. The spatial regression residuals were investigated for spatial correlation. The linear regression model and the spatial correlation of residuals together were used to predict theoretical crop yield at all locations using kriging with external drift. A spatial standard deviation comes along with this prediction, indicating the uncertainty of the prediction. In combination with land use data and country borders, we summed the crop yield predictions to determine an area total. With spatial stochastic simulation, we estimated the uncertainty of that total production potential as well as the spatial cumulative distribution function. We compared our results with the prevailing agro-ecological Climate Zones approach used for spatial aggregation. Linear regression could explain up to 70% of the spatial variation of the yield. In three out of four cases the regression residuals showed spatial correlation. The potential crop production per country according to the Climate Zones approach was in all countries and cases except one within the 95% prediction interval as obtained after yield aggregation. We concluded that the geostatistical approach can estimate a country’s crop production, including a quantification of uncertainty. In addition, we stress the importance of the use of geostatistics to create tools for crop modelling scientists to explore relationships between yields and spatial environmental variables and to assist policy makers with tangible results on yield gaps at multiple levels of spatial aggregation.  相似文献   
77.
78.
光辐射染色木材的变色规律及化学组分结构的变化   总被引:1,自引:0,他引:1  
以I-214杨木染色单板为试材、氙光作为辐射光源,考察其在100h光照过程中表面颜色的变化规律;依据红外光谱图的谱峰位置和谱峰相对吸收强度,分析和确定光变色过程中染色杨木木材的化学组分。结果表明:染色杨木木材受光辐射易发生变色,其中酸性蓝染色单板的明度指数L*和色品指数b*变化显著,其光变色度显著大于酸性大红GR染色单板;若以波数1510cm-1为基准,非共轭羰基C=O振动的吸收峰(1738cm-1)吸收强度显著增强;共轭羰基C=O伸缩振动的吸收峰(1650cm-1)吸收强度有所增强;芳香环骨架C-C振动的吸收峰(1510cm-1)吸收强度明显减弱;C-O-H振动的吸收峰(1160~1052cm-1)吸收强度有所减弱。  相似文献   
79.
刘蕙兰  张建中 《安徽农业科学》2011,39(36):22457-22460
针对宁夏地区农民传统住宅抗震性差,建筑外围护结构保温性能差,采暖系统能源消耗量大,环境污染严重等问题,提出采用轻钢结构配以轻质保温板材的轻钢结构抗震节能体系,以期为宁夏农村住宅设计提供指导性建议。  相似文献   
80.
By burrowing galleries and producing casts, earthworms are constantly changing the structure and properties of the soils in which they are living. These changes modify the costs and benefits for earthworms to stay in the environment they modify. In this paper, we measured experimentally how dispersal behaviour of endogeic and anecic earthworms responds to the cumulative changes they made in soil characteristics. The influence of earthworm activities on dispersal was studied in standardised mesocosms by comparing the influence of soils modified or not modified by earthworm activities on earthworm dispersal rates.The cumulative use of the soil by the earthworms strongly modified soil physical properties. The height of the soil decreased over time and the amount of aggregates smaller than 2 mm decreased in contrast to aggregates larger than 5 mm that increased. We found that: (i) earthworm activities significantly modified soil physical properties (such as bulk density, soil strength and soil aggregation) and decreased significantly the dispersal rates of the endogeic species, whatever the species that modified the soil; (ii) the decreasing in the dispersal proportion of the endogeic species suggests that the cost of engineering activities may be higher than the one of dispersal; (iii) the dispersal of the anecic species appeared to be not influenced by its own activities (intra-specific influences) or by the activities of the endogeic species (inter-specific influences). Overall these results suggest that the endogeic species is involved in a process of niche construction, which evolved jointly with its dispersal strategy.  相似文献   
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