人参提取物对蛋鸡产蛋性能、蛋品质、血清生化指标及经济效益的影响

文章旨在评估日粮添加不同水平人参提取物对蛋鸡产蛋性能、蛋品质及血清生化指标的影响。试验选择产蛋性能一致的450只海兰褐壳蛋鸡,随机分为3组,每组5个重复,每个重复30只。对照组饲喂基础日粮,处理组分别在基础日粮中添加0.04%和0.08%人参提取物,试验共进行6周。结果：与对照组相比,0.04%和0.08%人参提取物组产蛋率分别显著提高10.21%和8.77%（P＜0.05）,平均蛋重分别显著提高11.68%和9.07%（P＜0.05）。0.04%人参提取物组料蛋比较对照组显著降低6.51%（P＜0.05）,蛋壳颜色较对照组显著提高26.50%（P＜0.05）。对照组血清胆固醇浓度较处理组分别显著提高52.02%和58.32%（P＜0.05）。0.04%人参提取物组血清超氧化物歧化酶活性较对照组显著提高30.50%（P＜0.05）。0.04%和0.08%人参提取物组血清IgG和IgM浓度较对照组分别显著提高53.47%、60.72%和36.44%、42.43%（P＜0.05）。与对照组相比,0.04%和0.08%人参提取物组盲肠乳酸杆菌含量分别显著提高15.13%和12.82%（P＜0.05）。结论：在本试验条件下,日粮添加0.4?g/kg人参提取物可以提高蛋鸡饲料效率和蛋壳颜色。 [关键词]人参提取物|蛋鸡|产蛋性能|蛋品质|血清生化     

光敏核不育水稻的光温反应研究 Ⅲ.减数分裂期温度对两个籼稻光敏不育系育性转换的影响

在人工控制条件下研究了在15小时长光照下减数分裂期的不同温度(23.3～30.3℃)对籼稻光敏不育系W6154S和5460S育性转换的影响。结果表明,温度对育性的影响因温度的高低及处理持续时间长短而异,不同的材料对温度的反应不同。5460S从不育转为可育的临界温度在26.4℃左右,而W6154S在处理温度范围内均出现自交结实现象,表明供试的W6154S株系育性转换的临界温度可能超过30.3℃。提出了深入研究影响籼稻光敏不育系育性转换的临界温度的建议。     

光敏核不育水稻的光温反应研究

在人工控制条件下研究了在15小时长光照下减数分裂期的不同温度（23.3-30.3℃）对籼稻光敏不育系W6154S和5460S育性转换的影响。结果表明，温度对育性的影响因温度的高低及处理持续时间长短而异，不同的材料对温度的反应不同。5460S从不育的临界温度在26.4℃左右，而W6154S在处理温度范围内均出现自交结实现象，表明供试的W61     

达乌尔黄鼠(Spermophilus dauricus)生态学研究进展

达乌尔黄鼠(Spermophilus dauricus)是广泛分布于中国的主要啮齿类物种,栖息于森林、草原和农田耕地等各类生境中,具有个体小、数量多、适应性强、分布广等特征,携带鼠疫杆菌,对农、林、牧业危害和人类卫生健康影响较大。综述了其生态学和实验动物化开发与防控等方面的研究概况及其进展,展望了可能的研究方向和存有的问题。旨在为该物种的有效监测、综合控制和管理与开发利用等提供参考。     

温室营养液循环检测系统中离子选择电极的数学建模与测量

针对目前设施农业中使用离子选择电极对营养液养分进行在线测量所存在的长时间测量和测量准确性问题,提出使用基于最小二乘法的“逐步拟合法”拟合钾、钙、硝态氮等离子选择电极模型,建立被测溶液浓度,电极测量电压和被测溶液温度的三维数学模型。并由此设计出营养液各养分含量的在线测量方法。以钾离子选择电极为例介绍了离子选择电极的试验测量方法、建模原理和过程。通过建模得到了钾离子选择电极的一个以温度的一次函数作为常数项和测量电压自变量的系数项、溶液浓度为应变量的函数模型。大量的实验结果表明：所建立的离子选择电极模型准确,可用于在线检测,提出的方法在工程上简洁实用,具有广泛的应用价值。     

Organic manure stimulates biological activity and barley growth in soil subject to secondary salinization

A pot experiment was performed to compare the impact of organic manure on soil enzymatic activity, respiration rate and the growth of two barley cultivars (Hordeum vulgare L.) differing in their salt tolerance under a simulated salinized environment. A plastic pot with a hole (2 cm in diameter) in the center of bottom was filled with an anthropogenic (paddy) soil and placed in a porcelain container containing NaCl solution (3.0 g L⁻¹) such that a secondary salinization process was simulated via upward capillary water movement along the soil profile. A treatment with neither organic manure nor simulated soil salinization was taken as a control (CK1). The organic manure was applied either inside or outside rhizobag made of nylon cloth (40 μm of pore size). The soil was treated with: 20 g kg⁻¹ rice straw (RS), 20 g kg⁻¹ pig manure (PM), or 10 g kg⁻¹ rice straw plus 10 g kg⁻¹ pig manure (RS+PM). No organic manure was added in an additional control treatment (CK2). The results indicated that the placement of organic manure both inside and outside rihzobags significantly increased the activity of urease, alkaline phosphatase and dehydrogenase, as well as respiration rate in both rhizosphere and bulk soils. Also, nutrient uptake by barley plants was enhanced in the treatments with organic manure amended either inside or outside rhizobags. The activity of these enzymes along with the respiration rate was higher in rhizosphere than in non-rhizosphere when organic manure was supplied inside rhizobags, while the opposite was found in the case of manure incorporated outside rhizobags. Among all the treatments, RS+PM treatment had most significant stimulating effects on enzymatic and microbial activity and shoot dry weight of barley, followed by PM and RS. Moreover, more significant stimulating effects on both enzyme activity and plant growth were achieved in the treatments with manure amended inside rhizobags than outside rhizobags. The results of the present study confirmed the view that incorporation of organic manure especially into soil-root zones is an effective low-input agro-technological approach to enhancing soil fertility and minimizing phytotoxicity induced by secondary salinization.     

用卫星磁带图象制水土流失图的实验研究

自1972年美国发射资源卫星以后,国内外土壤学界纷纷用卫片来作为土壤调查的工具^[1-3,6]。在水土流失调查制图中也是如此^[9,11]。然而,由于卫星胶片信息损失达20%以上^[7]、目视判读的主观性和难于定量化,故即使用1/25万-1/20万的合成片调查判读,也只能达到1/50万-1/100万的调查制图精度。随着计算机图象处理技术和设备的发展,用卫星磁带图象进行分类制图的应用试验,日益增多,并取得了一定的进展^[5,10],甚至有的达到应用的程度¹⁾。这与卫星磁带图象的信息很少损失有关;同时也因这种技术具有比目视判读更客观、更定量的突出优点。因此,这种遥感技术有可能达到1八。万-1/20万的调查制图精度。     

Arsenite and arsenate leaching and retention on iron (hydr)oxide-coated sand column

Purpose

Arsenite and arsenate leaching from iron (hydr)oxides is one major parameter affecting the mobility of arsenic in the natural environment. In the process of arsenic transfer to groundwater, the retention capacity of arsenic by different iron (hydr)oxides needs to be investigated. The aim of this study is to determine the retention capacity of arsenite or arsenate from the ferrihydrite, lepidocrocite, or magnetite-coated sand column in the leaching process as well as the influence factors on leaching.

Materials and methods

The leaching of arsenite and arsenate from columns loaded with ferrihydrite, magnetite, or lepidocrocite-coated quartz sand was examined, and the influence factors such as pH, phosphate, and humic acid (HA) contents on leaching and retention were also investigated.

Results and discussion

The retention performance of As(III) and As(V) depended on the type of iron (hydr)oxides: ferrihydrite?>?magnetite?>?lepidocrocite. The retention capacities of As(III) and As(V) by amorphous ferrihydrite versus magnetite and lepidocrocite are 3.25, 5.63 (As(III)) and 1.75, 3.65 (As(V)) times higher. The retention capacity of arsenic is largely affected by the pH of leaching solutions. The retention of As(III) by ferrihydrite is efficient in near-neutral or slightly acidic environments. The addition of phosphate or HA significantly affected the leaching and retention. The addition of phosphate severely inhibited the leaching and retention of As(III) and As(V) by ferrihydrite, and the inhibitory effect was more obvious along with the increase of phosphate concentration. The retention of As(III) and As(V) by ferrihydrite was significantly enhanced by the addition of low-dose HA but was inhibited by the addition of excessive HA.

Conclusions

Retention performance of As(III) and As(V) from a ferrihydrite-coated sand column is greater than a magnetite- or a lepidocrocite-coated sand column, and the influence factors such as pH, phosphate, and HA affect the leaching and retention of As(III) and As(V). The results theoretically underlie the application of iron (hydr)oxide in arsenic pollution control.

     

凉城县黄土丘陵沟壑区水土保持生态经济林基础效益分析

凉城县黄土丘陵沟壑区营造的各种水土保持生态经济林 ,其水土保持基础效益十分显著 ,表现在延滞径流产生时间、减少径流量 ,涵养水源蓄存水量 ,缓冲雨强、减弱水力侵蚀强度 ,减少表土流失、控制土壤侵蚀 ,增加降水的有效性 ,培肥地力等方面 ,使生态环境得到较大改善 ,由此也收到较好的生态效益、社会效益和经济效益。对凉城县黄土丘陵沟壑区水土保持生态经济林的保水保土效益做出的客观分析论述 ,为该县进一步合理利用宜地林资源、促进生态环境建设提供依据 ,也为其它受水土流失危害的黄土地区提供借鉴。     

苏北滨海盐渍土中颉抗性放线菌的分布

放线菌是土壤微生物的重要组成部分。与其它微生物相比,它是产生抗菌素较多的菌类。由于医药工业和农业病害防治上的需要,长期以来对放线菌的研究,几乎都围绕在颉抗性放线菌的筛选工作上。有关它们在土壤中的作用,特别是对放线菌生态因素方面的研究,国内外报道均甚少^[3,7,6]。本文主要介绍土壤盐渍化对放线菌分布及颉抗特性的影响。