集雨限灌对旱作马铃薯产量及水分利用效率的影响

在大田条件下研究了集雨有限补偿灌溉对旱区马铃薯产量及水分利用效率的影响。结果表明,补灌能显著提高旱作马铃薯的产量、水分利用效率和经济系数。与对照相比,补灌处理产量增幅在3.99%~21.21%之间,苗期补灌产量高于薯块膨大期补灌,苗期补灌45 mm具有超补偿效应,补灌90 mm具有高补偿效应。低定额补灌有利于水分利用效率和灌水利用效率的提高,且苗期补灌高于薯块膨大期补灌。补灌明显降低了薯块小薯率而提高了大薯率和中薯率,另外单株薯重也提高了,单株薯重与大薯率对马铃薯的产量贡献最大。综合分析认为苗期补灌45 mm和90 mm是最优补灌方案和备选方案。     

龟石灌区节水改造的潜力与效益分析

针对龟石灌区农业用水效率低下、浪费严重等问题，提出了节水措施，分析了节水改造的潜力与效益。灌区水资源优化配置与合理利用，提高灌溉水利用率和水分生产率，富余水量用于城市供水及发电，提高单位水量的价值不仅是必要的，而且是灌区发展的必由之路。     

杂交早稻吸氮特性与产量形成的初步研究

研究了在不同施氮水平下,杂交早稻吸氮特性及其与产量形成的关系。结果表明;杂交早稻威优49亩产500千克左右,植株每亩总吸氮量平均为9.78千克,其中土壤供氮量占52.45%。杂交早稻一生中前期吸氮量占50.72%,中期占31.08%,后期占18.30%,以中期施氮对叶片含氮率影响最大。在高氮水平下,中期施氮导致茎鞘醣含量急剧下降。抽穗前植株吸氮量与每亩发育颖花数呈极显著正相关,但结实率受每朵颖花占有抽穗前醣量的影响。最适 LAI 为6.5～7.5。     

反硝化聚磷一体化设备中微生物数量变化的研究

对反硝化聚磷除磷脱氮污水处理新工艺运行初期系统中的微生物数量进行了跟踪检测，并对细菌总数，霉菌，放线菌，硝化细菌，亚硝化细菌，反硝化细菌在不同日期的数量变化进行了研究。     

施肥对红三叶群落营养元素含量和积累量的影响

本文研究了施肥对红三叶群落地上部和地下部 1 0种营养元素的影响 ,结果如下 :( 1 )从含量看 ,施氮肥后 ,地上部B明显降低 ,地下部B明显升高 ;施磷肥后 ,地上部N、B显著下降 ,地下部K、P、N上升幅度较大。 ( 2 )就积累量而言 ,施氮肥后 ,地上部大多数元素增高 ,地下部多数元素降低或无变化 ;施磷肥后 ,无论地上部还是地下部 ,大多数元素均有所增高     

霉形体膜蛋白溶解及含量测定方法研究

本文选择双蒸水；０．１ｍｏｌ／ＬＮａＯＨ；１．０ｍｏｌ／ＬＮａＯＨ；４％ＤＯＣ和１％ＳＤＳ条件分别对猪肺炎霉形体膜制剂作增溶处理，使膜蛋白溶解，然后采用Ｌｏｗｒｙ法进行蛋白质含量的测定．测定结果表明：０．１ｍｏｌ／ＬＮａＯＨ溶解效果较好，所测得膜蛋白含量达６８．８％左右。，数据更为接近实际含量．     

Physiological Basis of Irrigation Scheduling for Seed Production in Egyptian Clover Syn. Berseem (Trifolium alexandrinum L.) Crop

A field experiment was conducted to find out the critical physiological stages of irrigation schedules inducing better growth, physiological efficiency and seed yield potential of berseem ( Trifolium alexandrinum L., Var. S-99-1). For this purpose eight irrigation treatments were made comprised of four treatments of three irrigation (W₁, W₂, W₃ and W₄), three treatments of four irrigation (W₅, W₇ and W₈) and one treatment of five irrigation (W₆) at various physiological stages i. e. regeneration, flower initiation, full bloom, seed initiation and advance seed development stage.
Thus based on the experimental results the physiological role of watering in berseem seed production could be discussed as:
With-holding of irrigation either at regeneration or at full bloom stage developed potential water stress in plants as indicated by high proline content of irrigation treatments — W₄, W₁ and W₇; and further brought out disturbance on the formation of carotene, synthesis of water soluble sugar and translocation of sugar towards reproductive organs during grain development stage. These stresses adversely affected the plant growth and flowering behaviour. The irrigation at seed initiation stage increased the seed yield. Continuous irrigation did not appear to be useful. Thus it can be concluded that irrigation at three critical physiological stages i. e. regeneration, full bloom and seed initiation was found to be essential for obtaining potential seed yield of berseem.     

Impact of pig slurry on soil properties, water salinization, nitrate leaching and crop yield in a four-year experiment in Central Spain

Abstract. The repeated application of pig slurry to agricultural soils may result in an accumulation of salts and a risk of aquifer pollution due to nitrate leaching and salinization. Under Mediterranean conditions, a field experiment on a sandy loam soil (Typic Xerofluvent) was performed with maize (Zea mays) in 1998, 1999 and 2001 to study the effects of applying optimal (P1) and excessive rates (P3) of pig slurry on soil salinization, nitrate leaching and groundwater pollution. The rate of pig slurry was established considering the optimal N rate for maize in this soil (170, 162 and 176 kg N ha^?1 for 1998, 1999 and 2001, respectively). Pig slurry treatments were compared to an optimal N rate supplied as urea (U) and a control treatment without N fertilizer (P0). The composition of the slurries showed great variability between years. Mean NO₃^? leaching losses from 1998 to 2001 were 329, 215, 173 and 78 kg N ha^?1 for P3, P1, U and P0 treatments, respectively. The amount of total dissolved salts (TDS) added to the soil in slurry application between 1998 and 2001 was 2019 kg TDS ha^?1 for the P1 treatment and 6058 kg TDS ha^?1 for the P3 treatment. As a consequence, the electrical conductivity (EC) of the slurry‐treated soils was greater than that of the control soil. The EC correlated significantly with the sodium concentration of the soil solution. Over the entire experimental period, 2653, 2202 and 2110 kg Na ha^?1 entered the aquifer from the P3, P1 and P0 treatments, respectively. The P3 treatment did not significantly increase grain production in 1999 and 2001 compared with that achieved with the optimal N rate treatment (P1). This behaviour shows the importance of establishing application guidelines for pig slurry that will reduce the risk of soil and groundwater pollution.     

哈达门国家森林公园游客量动态预测

根据哈达门国家森林公园的票房数据，应用灰色系统理论建立旅游量灰色动态模型。基此，对哈园游客量进行了中短期预测，其预测检验精度为９３．７２。旨在对该园建设、管理等项决策提供科学依据。     

林木资源消耗量估测方法的初步研究

本文主要通过应用统计学的有关知识,提出适应南方集体林区木材市场开放新格局的一种估测林木资源消耗量的方法;并将这种方法在沙县进行了实地验证;分析了其可靠程度与经济意义。