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51.
Ken R. Ito Tomonori Sato Hiro Goto Katsuyoshi Sato Jun Watanabe Masaki Yokoo 《The Journal of Poultry Science》2022,59(3):247
Increasing food loss and waste (FLW) is a global problem, and efforts are being made to use waste food as potential livestock feed material. The amount of self-supplied feed is lower in Japan than in other countries, and the government recommends FLW use for animal feed. Sake (Japanese rice wine) is a traditional alcoholic beverage. During the sake manufacturing process, large amounts of squeezed solids or “lees” (sake lees) are generated. Sake lees are nutritious and functional, but are prone to spoilage. In this study, we investigated whether sake lees should be mixed with animal feed immediately or after drying. To assess the usefulness of sake lees as a poultry feed ingredient and determine the effect of sake lees on intestinal immunity, we performed a feeding trial with three treatments: a raw sake lees (RSL) diet, dried sake lees (DSL) diet, and control diet. Three-week-old broilers were fed these diets (n=8 per group) for two weeks. We then calculated feed efficiency and performed RT-qPCR to assess the effects of diet on intestinal immunity. The growth performance in the RSL diet group was equivalent to that in the control diet group. The DSL diet became difficult for broilers to eat, resulting in decreased growth performance. In the ileum of RSL-diet broilers, the mRNA expression levels of TGF-β1 and avian β-defensin (AvBD)12 were significantly increased compared to those of control diet broilers (p<0.05), and a significant correlation was observed between the two genes (p<0.05). Our results indicated that sake lees should not be dried and should be mixed immediately with feed, and this sake lees when fed to chicken activates the intestinal immunity. However, sake lees have a lower fat content than corn, and it is thus important to combine sake lees with high-energy feed. 相似文献
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The effects of wind turbines and other physical landscape elements on field utilization by wintering pink-footed geese (Anser brachyrhynchus) were studied in a Danish farmland landscape. Within the study area geese were feeding on pastures, which together with cereals were the main crop types. Apart from wind turbines a variety of potentially disturbing landscape elements was present, e.g., high-power lines, windbreaks, roads and settlements. Patterns of field use were assessed by measuring goose dropping densities along transects perpendicular to wind farms (with turbines in clusters and in lines) and other landscape elements. Local effects were expressed in terms of `avoidance distance', i.e., the distance from a given landscape element to the point at which 50% of maximal dropping density was reached. The spatial distribution of landscape elements within an eight km radius from the goose roost was determined from aerial photographs. The area occupied by various elements, together with the adjacent zones which were not available to geese due to their associated avoidance distances, were quantified using Geographic Information System (GIS).The avoidance distance of wind farms with turbines in lines and in clusters were ca 100 m and ca 200 m, respectively. Geese did not enter the area between turbines within the cluster. At the landscape level, the combined effect of physical elements other than wind turbines caused an effective loss of 68% of the total field area (40 km2). Wind turbines caused an additional loss of 4% of the field area. However, of the remaining area available to geese (13 km2), wind turbines caused a loss of 13% of the total area. The habitat loss per turbine was higher for the wind farm with turbines arranged in a large cluster than for wind farms with turbines in small clusters or lines. This difference was mainly due to the fact that wind farms in small clusters or with a linear layout were generally placed close to roads or other elements with existing associated avoidance zones, whereas the large cluster was placed in the open farmland area. The avoidance zones associated with physical elements in the landscape do not take into account possible synergistic effects and, hence, actual field areas affected are likely to be minimum estimates. Implications of these findings for planning of wind farms in areas of conservation interest to geese are discussed. 相似文献
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Gizaw Desta Lulseged Tamene Wuletawu Abera Tilahun Amede Anthony Whitbread 《国际水土保持研究(英文)》2021,9(4):544-554
Identifying land management practices (LMPs) that enhance on-site sediment management and crop productivity is crucial for the prevention, reduction, and restoration of land degradation and contributing to achieving land degradation neutrality (LDN). We reviewed studies in Ethiopia to assess the effects of LMPs on soil loss (84 studies) and crop productivity (34 studies) relative to control practice. Yield variability on conserved lands was assessed using 12,796 fixed plot data. Effects of LMP on soil loss were 0.5–55 t ha−1y−1 compared to control practices yielding 50 to 140 t ha−1y−1. More than 55% of soil loss records revealed soil loss less than the tolerable rate (10 t ha−1). Area closure, perennial vegetation cover, agronomic practices, mechanical erosion control practices, annual cropland cover, and drainage groups of practices led to 74.0 ± 18.3%, 69.0 ± 24.6%, 66.2 ± 30.5%, 66.1 ± 18.0%, 63.5 ± 20.0%, and 40 ± 11,1% soil loss reduction, respectively. A yield increase of 25.2 ± 15.0%, 37.5 ± 28.0%, and 75.4 ± 85.0% was found from drainage, agronomy, and mechanical erosion control practices, respectively. The average yield loss by erosion on fields without appropriate land management practice and on conserved fields was 26.5 ± 26.0% and 25 ± 3.7%, respectively. The findings suggest that practices that entail a continuous presence of soil cover during the rainy season, perennial vegetation, retention of moisture, and barriers for sediment transport were most effective at decreasing soil loss and increasing productivity. This review provides evidence to identify the best LMP practices for wider adoption and inform decision-making on LMP investments towards achieving sustainable solutions to reverse land degradation. 相似文献
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在河南省鹤壁和原阳采用田间试验,研究不施氮(CK)、种肥同播(T1)、5叶期一次性施肥(T2)和10叶期一次性施肥(T3),对夏玉米生长发育、氮素积累转运及产量的影响,明确夏玉米包膜尿素1∶1配施普通尿素适宜的一次性施肥时期。结果表明,鹤壁和原阳T1处理产量最高,分别为12 700 kg/hm2和10 945 kg/hm2,但与T2处理间差异不显著,较T3处理分别提高14.2%和10.9%;干物质积累量较其他处理分别提高5.6%~25.1%和1.6%~21.2%。不同生育期T1处理叶片SPAD值和叶面积指数均达最高。鹤壁和原阳T1氮肥表观利用率最高,分别为35.2%和35.5%,较其他处理分别提高5.6~14.7个百分点和3.2~13.6个百分点;氮素积累量较其他施氮处理分别提高13.8%~34.5%和14.5%~41.5%。T1处理土壤氮素依存率低于T2和T3处理。综上,种肥同播提高了夏玉米产量、氮肥效率、叶片SAPD值和叶面积指数,保持较高的氮素吸收速率,降低了土壤氮依存率,满足夏玉米整个生育期的氮素需求,实现了夏玉米高产和高效施肥。 相似文献
57.
密云水库上游流域氮流失规律研究 总被引:2,自引:0,他引:2
以1212.69km^2的密云水库上游流域为研究对象,研究了氮素在大尺度范围内的流失规律。结果表明,雨季中、雨季后氮的流失量明显高于雨季前,分别为雨季前的2.9倍、2.36倍;位于下游的监测点氮的浓度偏高;随着雨季的到来旅游景点、果园径流中氮的浓度会明显增加;各项污染物的季节变异系数较大的点,位于农业活动比较剧烈和径流季节变异较大的区域,而在水库或塘坝污染物的季节变异较小。不同水文期,河流水体中氮素的主要形态不同,各监测点雨季前、雨季后以溶解态氮为主,雨季中溶解态氮所占比例有所下降,在部分河道以颗粒态为主。雨季前径流中氮的流失以NO3^--N为主,约占总氮的65%,随着雨季的来临所占比例有所下降。 相似文献
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为研究塑料与稻壳共燃的氮氧化物生成规律,在自行设计的循环流化床装置上进行了二者的共燃实验。研究了温度、塑料粉和稻壳的混合比例及过量空气系数对NO生成量的影响。实验结果表明,随温度升高,NO生成量升高;随塑料粉与稻壳混合比例增加,NO生成量呈降低趋势,且NO的生成量低于二者单独焚烧时生成量的线性叠加;随着过量空气系数增加,NO生成量降低。为寻找二者共燃NO生成的一般性规律,采用径向基神经网络建立了NO生成的预测模型,预测结果显示该模型具有很高的精度。 相似文献
60.
东露天煤矿区采矿对土地利用和土壤侵蚀的影响预测 总被引:2,自引:2,他引:0
黄土区大型露天矿区是一种剧烈的人工扰动区域,采矿活动对土地资源和生态与环境破坏非常严重,正确预测人工开采引发的人为加速土壤侵蚀与土地利用变化,可为生态脆弱煤矿区的生态恢复和重建提供依据。该文采用RS、GIS技术、统计分析、类比和趋势外推相结合的方法,对东露天矿区2005~2080年的土地利用变化和水土流失进行了预测性研究。结果表明:75年间,在没有采取生态重建的措施下,农用地减少3666.07 hm2,未利用地减少1402.13 hm2,居民点用地减少121.80 hm2,全部变为独立工矿用地。土地利用结构和类型由多样性向单一类型的裸露的独立工矿用地发展,水土流失量由54.50万t/a变为77.85万t/a。 相似文献