排序方式: 共有4条查询结果,搜索用时 15 毫秒
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应用地统计学的方法,研究了祁连山北坡石羊河上游,6—10月之间红腹牧草蝗Omocestus haemorrhoidalis(Charpentie)雌雄虫的空间分布格局、动态变化及空间相关性。结果表明:红腹牧草蝗雌雄虫的半变异函数为球状模型与高斯模型,二者空间分布类型相同,均呈聚集分布;随时间的变化均呈现"扩散-聚集-扩散-聚集"的动态特征,7—8月之间雌虫的变化强度明显强于雄虫;二者的模糊贴近度指数在0.53~0.71之间,且指数随红腹牧草蝗的生长呈逐渐增加到减少的变化特征,表明雌雄虫在数量与空间上有较强的跟随关系,且跟随关系随红腹牧草蝗的生长发生明显的阶段性变化。 相似文献
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José Antonio Rodríguez Martín Antonio Vazquez de la Cueva José Manuel Grau Corbí Celia Martínez Alonso Manuel López Arias 《Soil & Sediment Contamination》2009,18(1):30-42
This study characterized the sources and scales of mercury variability in agricultural soils of the river Ebro (9.5 million ha) using geostatistical methods and data from 624 samples. The Ebro basin (20% of Spanish land mass) is an important agricultural area that is industrialized. Spatial analysis was done on a local scale (20 km) and indicated that high Hg concentrations were related to mining and specific agronomic practices, such as sewage effluents from irrigation. The intermediate scale (100 km) was associated with mercury from atmospheric deposition (mining, smelting, and industrial activities). The regional scale (220 km) corresponded to mineralogical structure and bedrock influence. The analysis demostrates that while geographical and geochemical processes and anthropogenic influences, such as industrialization and agricultural practices, can influence the content and distribution of mercury in the valley, the calcareous nature of the soils (alkaline pH and low organic matter) minimize the effect of the mercury load. 相似文献
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越北腹露蝗若虫空间格局的地学统计学分析 总被引:10,自引:0,他引:10
应用地学统计学研究广东北部桑田中越北腹露蝗(Fruhstorferiola tonkinensis Will)1~5龄若虫的空间格局动态.结果表明:越北腹露蝗1~5龄若虫种群变异曲线函数均为球状模型,表现为聚集分布,但各龄若虫的空间依赖范围分别为1.973、1.968、2.169、2.302和4.307 m.利用Kriging插值法由地学统计学软件Surfer 8.0产生的各龄若虫等值线图清晰地反映了各龄若虫的空间位置, 表明越北腹露蝗有别于其它一些蝗虫,其低龄若虫呈聚居型,高龄若虫呈散居型分布. 相似文献
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