生物能温室对水稻生长发育影响的研究

生物能温室比烧火温室育水稻秧苗无论在温度、湿度、光照、气体均利于秧苗生长发育,室内CO₂浓度可高出大气4倍多。并可防治早春低温阴雨对水稻分蘖期和低温对齐穗期的影响。     

Use of poultry manure and plant cultivation for the reclamation of burnt soils

Annual (Pisum sativum L. and Vicia sativa L.) and perennial (Trifolium repens L. and Lotus corniculatus L.) leguminous species were grown in pots containing samples from the ash layers of two Cambisols under Pinus sylvestris L., which has been affected by high-intensity wildfires 3 and 15 days before the sampling. The gramineous Lolium perenne L. was cultivated as a second plant after Trifolium and Lotus harvesting. Three treatments were compared: soils without fertilization and soils fertilized with two doses of poultry manure (1 and 2 g total N kg^-1 dry soil). The aim of the work was to study the capacity of the ash layer to sustain vegetation and the influence of plants and organic manure on the recovery of vegetation cover, ash layer fixation and soil structure formation to avoid erosion. The ash samples were able to sustain vegetation without fertilization. The organic manure increased the yields of all the plants tested, the lower dose being the optimal for the first crop whereas the higher dose was beneficial for the second crop. The annual legumes grew very quickly. The mixture of Trifolium and Lotus seemed very suitable for reclamation of soil degraded by wildfires because Trifolium produced more phytomass than Lotus in the first growing stages whereas the development of Lotus was higher in the later growing stages. Ash layer conditions did not inhibit nodulation, which was, however, stimulated by the organic manure, particularly in the case of Lotus. Lolium after perennial legumes was the best plant combination because it produced the highest phytomass, particularly root phytomass, and thus improved vegetation cover and ash layer fixation. All the plants tested improved the formation of soil aggregates, particularly the combination of perennial legumes and Lolium. However, wet aggregate stability was higher when plants were grown on soils fertilized with poultry manure than when plants were cropped on unmanured soils, which points to the favourable influence of the organic manure on soil aggregation.     

Coordinated pest management decisions in the presence of management externalities: The case of greenhouse whitefly in California-grown strawberries

Optimal pest management can be compounded by externalities associated with management decisions among adjacent crop fields managed by agricultural producers. In this paper, a bioeconomic model is used to measure the effects of management decisions on optimal pest management. The case of the greenhouse whitefly invasion of California-grown strawberries is considered. Results show that coordinated pest management decisions among host crop growers may improve returns, but only during certain parts of the strawberry growing season. Two generalizable pest management policy implications are presented.     

桐油控释复合肥在烤烟上的应用效果

以自然资源桐油为控释材料(从油桐果实中提取),生产控释肥料,进行烟草温室无土栽培盆栽试验,研究桐油控释复合肥在烤烟上的应用效果。结果表明:在温室环境条件下,桐油控释复合肥的养分初期溶出率为2.8%;施用控释复合肥的产量高出普通复合肥处理26.7 g/株;桐油控释复合肥与普通复合肥相比,每克肥料要多生产烤烟2.2 g。说明桐油控释复合肥具有很好的生产性。     

温室黄瓜叶面积计算及其与株高的相关性研究

利用5个黄瓜品种进行不同季节日光温室和现代温室的栽培实验,提出了一个简易的温室黄瓜叶面积计算经验公式,用长宽法计算温室黄瓜叶面积的矫正系数K=0.743。研究了温室黄瓜叶面积与株高的变化规律,二者间呈极显著线性相关,相关系数为0.991。提出了利用着叶株高替代叶面积,以实现温室黄瓜模式化研究的简化处理。     

GRP新型温室覆盖膜温热特性的研究

为解决现有温室塑料覆盖膜使用寿命短、变光性能差、造价高的问题, 研制成功了经济耐用、变光性能优的GRP新型覆盖材料。在实验基础上, 运用现代数理统计方法, 初步分析了GRP温室覆盖材料的温热特性, 防雾和防滴性能及对栽培作物产量的影响。结果证明, GRP膜具有良好的温热性与保温性, 在最低气温条件下, 试验温室室内最低气温比对照温室室内气温高2℃, 而最高气温均为32℃; 在阴天, GRP膜的增温效果较EVA膜好,最好时比对照温室内气温高3 30℃。另外, 在实验期间, 试验温室从未见过起雾, 滴水也很少, 说明新材料具有良好的防雾、防滴性能。因此, GRP膜对作物生产具有明显的增产效应, 与对照温室相比, 增产幅度高达16 2%。     

旱地农田N2O、CO2排放主要影响因素及研究进展

旱地农田是大气CO₂和N₂O的重要排放来源,农业生产活动对全球气候变化有着重要影响。全球气候变暖已成为不争的事实,探索农田温室气体排放情况对缓解气候变暖,实现农业节能减排具有重要意义。综述了旱地农田土壤N₂O和CO₂排放机理、影响因素和减排措施。结果表明：旱地农田N₂O和CO₂排放受土壤理化性质和田间管理措施多种因素影响。针对减少旱地农田N₂O和CO₂排放主要从合理施肥、灌溉和优化农作措施方面入手,因地制宜,“固碳”和“减排”同步,实现增产增汇减排的可持续发展农业。     

番茄整果在常温贮藏中的蠕变特性试验

蠕变特性是评价番茄果实品质的一个重要指标.本试验应用Instron万能试验机对常温贮藏的整番茄进行了蠕变特性的试验,对蠕变特性四参数、压缩弹性模量E、坚实度Fi、糖度及pH值等指标的变化规律进行了分析.结果表明:蠕变特性的粘弹性系数与压缩特性指标出现先下降,后逐渐上升,至第9 d达到最高峰,然后呈急剧下降的趋势.在常温贮藏期间,番茄的糖度和酸度均缓慢增加.     

晋南日光温室土壤微生物及土壤酶活性变化规律研究

笔者通过对晋南地区日光温室土壤微生物状况和土壤酶活性进行分析研究,结果显示:晋南地区日光温室土壤微生物总量由南往北呈增加趋势,显现出明显的地域性变化规律;随着种植年限的延长,土壤微生物总量和脲酶活性增加,过氧化氢酶活性保持相对稳定水平;土壤有机质含量和土壤微生物总量呈明显正相关,但生物总量的增加量远大于有机质的增加量,这可能是温室土壤有机质水平较低的原因之一。     

地源热泵技术在中国温室设施中的应用探讨

当前在中国温室设施中应用和推广地源热泵技术尚存在诸多不利因素,大大限制了该项技术在设施农业领域中的发展。为探寻合理的解决途径,对地源热泵空调系统的关键技术和其在中国的发展概况进行了相关的阐述和分析,并以中国农业大学上庄实验站已经建成使用的地下水式温室地源热泵空调系统为实例,介绍该系统的组成、工作流程、性能参数和使用情况,探讨温室地源热泵空调系统在推广和使用中可能出现的投资较高,长时间运行性能不稳定等问题,分析其原因并提出相应的对策建议。