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浙江嵊泗列岛,中街山列岛的岩礁上,生长着大量自然生裙带菜。因其形态上与北方裙带菜有明显差异,称它为南方型裙带菜。 相似文献
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萨福克、无角道赛特是世界著名肉用羊早熟品种,山西省介休种羊场分别于1999年7月和9月、2000年5月连续三次由澳大利亚和新疆引进这两个品种计96只种羊进行纯种繁育,到2002年底经过两个完整的畜牧年度饲养实践,认为萨福克和无角道赛特羊能够很好地适应山西省晋中盆地的自然环境条件,生长繁育指标均可达到或接近国外资料对这两个品种的要求。通过纯种繁育,核心羊群数量增加,同时向省内推广种羊近百只。1饲养地自然条件山西省介休种羊场位于晋中盆地南端,在介休城东北面。地区海拔740m,属半干旱大陆气候。全年平均气温11.5℃,1月平均气温-4℃7… 相似文献
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浙江省上虞县北部沿海有广阔的滩涂,现已围海涂13万多亩,其中咸淡水水面约1万亩,不能种植作物的低洼地近2万亩.为发展海水养殖;1981年,该县水产部门利用海涂低洼地挖了10.5亩水深1.5米的池塘,进行鲻鱼和白鲢、杂交鲤、福寿鱼混养试验.五个多月后,平均亩产达400斤,其中每亩净产鲻鱼180斤.1982年扩大了试养面积,鲻鱼亩产预计190斤以上.这一试养使人们看到了海涂挖塘养 相似文献
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施氮量·密度和苗龄对稻田免耕油菜苗期干物质积累的影响(英文) 总被引:1,自引:0,他引:1
[Objective] The aim of the research was to find the optimal nitrogen application rate, density and seedling age for no-tillage rape in seedling stage. [Method] With the D-optimal quadratic regression design for three factors, the 310 scheme was designed to study the effects of nitrogen application rate, density and seedling age on dry matter accumulation of no-tillage rape in seedling stage. [Result] With the increase of nitrogen application rate, density and seedling age, the dry matter content appeared like a parabola, increasing firstly and then declining. The change of nitrogen application rate caused greater influence than that of density and seedling age; the interaction effects between nitrogen application rate and density were greater than that between nitrogen application rate and seedling age as well as between density and seedling age. [Conclusion] Considered comprehensively, the dry matter content of no-tillage rape in seedling stage reached the highest level (4 768.2 kg/hm2) when the nitrogen application rate, the density and the seedling age were 195 kg/hm2, 93 000 plants/hm2 and 33 d, respectively. 相似文献
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施氮量、密度和苗龄对稻田免耕油菜苗期干物质积累的影响 总被引:1,自引:0,他引:1
[目的]寻求稻田免耕栽培条件下油菜适宜的施氮量、密度和苗龄。[方法]运用三因素二次回归饱和D-最优设计310方案,研究施氮量、密度和苗龄对稻田免耕油菜苗期干物质积累的影响。[结果]稻田免耕油菜苗期干物质含量随着施氮量、密度、苗龄的增加,呈现先升后降的抛物线。其中施氮量的变化量对干物质积累的影响大于密度和苗龄;施氮量与密度互作效应大于施氮量与苗龄和密度与苗龄的互作效应。[结论]综合考虑,施氮量在195 kg/hm2、密度在93 000株/hm2、苗龄在33 d时,免耕油菜苗期干物质含量达到最高(4 768.215 kg/hm2)。 相似文献
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