甘蔗光降解地膜与普通地膜不同覆盖方式对比试验

通过新植甘蔗采用光降解地膜与普通地膜不同覆盖方式对比试验,结果表明：两种地膜全膜覆盖较半膜覆盖与不盖膜具有较好的增温保湿作用,农艺性状表现较好,增产增糖效果明显.全膜覆盖平均蔗茎产量10595kg/667m2,较半膜覆盖增产1748 kg/667m2、增19.8％,差异达5％显著水平;较不盖膜增产2650 kg/667m2、增33.4％,差异达1％极显著水平.试验实施90d未发现光降解膜降解破口迹象,降解效果不理想.     

袋栽金针菇2潮后脱袋增产技术研究

为满足商品性要求,袋栽金针菇2潮后一般不再进行出菇管理。实际上,这时的菌棒仍有出菇趋势,由于塑料皮限制其生长,且阻碍补水补养,致使无法产生商品性好的菇,培养基中养分无法利用充分。试验中割破塑料皮,采用脱袋排场盖膜法和脱袋拱棚盖膜法进行继续出菇管理,并设置对照。结果表明,2种措施可分别再出菇3潮,生物学效率分别提高34％和28％,商品性满足三级以上标准,是可推广的金针菇增产措施。     

Factors (type,colour, density,and shape) determining the removal of marine plastic debris by seabirds from the South Pacific Ocean: Is there a pattern?

1. While floating near the sea surface plastic debris interacts with a number of external factors, including many different organisms. Seabirds have the most extensive documented history of interactions with plastics, through ingestion, entanglement, and nest construction.
2. In the present study, eight seabird species from the South Pacific Ocean were used as a proxy to determine potential patterns of removal of marine plastic debris, and three hypotheses were tested in relation to their feeding habits and nesting areas.
3. Plastics from abiotic compartments (Chilean continental coast, South Pacific Gyre, and Rapa Nui beaches) and biotic compartments (surface-feeding seabirds, diving seabirds, and nesting areas) were compared, according to their type, colour, shape, and density.
4. Continental beaches had a relatively wide range of colours and shapes, with many non-buoyant plastics. Samples from the South Pacific Gyre (SPG) and Rapa Nui (Easter Island) beaches comprised mainly hard, rounded, buoyant, and white/grey plastics.
5. These results indicate that the composition of floating plastics from terrestrial sources changes during transport with oceanic currents, reducing the proportion of prey-like plastics present in the subtropical gyres.
6. The stomach contents of surface-feeding and diving seabirds were dominated by hard, white/grey, and round plastic items, similar to plastics from the SPG, suggesting non-selective (accidental or secondary) ingestion.
7. Nesting areas had a more variable composition of brightly coloured plastics, suggesting a pattern of selective removal of plastics by seabirds, probably from oceanic sources.
8. The present study reveals extensive interactions of seabirds with plastics on a broader scale, which is highly relevant given that the impacts of plastics on seabirds are increasing worldwide, compromising their efficient conservation.

     

花生覆膜栽培技术要点

根据农机与农艺相结合的原则,从地块选择、种子处理、地膜选用、铺膜要求、田间管理、除草、收获等方面,探讨花生覆膜栽培技术要点,为提高花生的产量和品质提供理论参考。     

玻璃温室与塑料温室春季保温性能比较

以双屋脊玻璃温室和双脊窗圆拱型薄膜温室为研究对象,观测春季时典型晴天和典型阴天天气条件下2种温室内的气温及地温日变化。结果表明:晴天及阴天时,玻璃温室的日均气温和日均地温均比塑料温室高。晴天时玻璃温室的室内最高气温、最低气温以及日均气温分别比塑料温室高1.7、0.6、1.5℃;玻璃温室的室内最高地温、最低地温以及日均地温分别比塑料温室高1.3、0.9、1.1℃。阴天时玻璃温室的日均气温、日均地温分别比塑料温室高0.5、0.6℃。因此,在保温性能方面,玻璃温室优于塑料温室。     

15%多效唑对覆膜除草花生的生长影响

试验研究覆盖除草地膜的花生在花期后喷施15%多效唑对花生生长的影响。结果表明,覆盖除草地膜的花生在结荚初期到结荚中期,喷施15%多效唑能明显抑制花生主茎和侧枝的徒长,协调花生营养生长和生殖生长,促进荚果的发育、提高单株结果数、结实率,从而实现花生的增产。     

新型地膜覆盖对玉米增产效应试验研究初报

以玉米为试验对象,研究采用不同地膜覆盖对农作物生长及产量的影响。结果表明：覆盖常规地膜、中达转蓝光膜、中达转红光膜均可明显改善玉米生育性状,使成熟期提前10 d,增产效果显著。其中以中达转蓝光膜增产效果最好,667 m2增产达65.57 kg,增产率为10.03%。     

土壤改良剂对大棚辣椒连作土壤理化性质的影响

[目的]为了研究土壤改良剂对上海高桥地区不同连作年限土壤理化性质的影响。[方法]选取连作年限土壤为1、5和6年的3个大棚,分别测定土壤p H、电导率、有机质、全氮、全磷、全钾等主要养分含量。[结果]施用土壤改良剂能够有效缓解土壤盐渍化和酸化程度,显著增加土壤有机质含量,均衡土壤营养元素,改善施用有机肥导致的元素富集现象,明显改良土壤理化性质。[结论]在上海高桥地区的农业实际生产中,施用主要成分为石灰氮、秸秆和有机质的土壤改良剂是切实可行的,能够明显改善高桥地区土壤的理化性质。     

仿真固沙灌木林与塑料网方格沙障防风固沙效能比较

干旱区的水资源限制了植物治沙应用范围,将仿真固沙灌木加入退化梭梭林,比较仿真固沙灌木＋梭梭的灌木林与塑料网方格沙障防风固沙效能,为仿真固沙灌木应用提供参考。在野外相同条件下观测比较仿真固沙灌木林与塑料网方格沙障内风速,结果显示：仿真固沙灌木＋梭梭灌木林的风速削减率与塑料网方格沙障的差异不显著;随着风速增大,仿真固沙灌木降低风速率与塑料网方格沙障降低风速率差异变小;在风速为8.1~8.9 m s-1时,仿真固沙灌木降低风速率达塑料方格沙障的80%;仿真固沙灌木＋梭梭灌木林的输沙率随高度变化为指数递减,是裸沙地的35%;仿真固沙灌木林的建立不受气候条件影响,可重复应用,与灌木搭配可增强防风固沙效能。     

基于模糊理论玻璃钢游艇总纵弯曲可靠度计算

基于玻璃钢游艇材料在被破坏时的模糊性,建立了模糊状态下玻璃钢游艇的可靠性模型,并计算了一艘玻璃钢游艇的总纵弯曲下的艇体结构可靠度.针对正态分布的结构极限方程和非正态分布的模糊变量,应用JC法计算结构经典可靠度;采用隶属度函数进行模糊可靠度的计算.最后,将计算的玻璃钢游艇总纵弯曲下的结构模糊可靠度结果与经典可靠度下的计算结果作对比,提出模糊可靠度的合理性及经典可靠度的保守性的结论.