Root function in uptake of nutrients and the effect of soil water on the transfer and distribution of NO3^--N in arable soil were studied using summer maize （Zea mays L. var. Shandan 9） as a testing crop. Results sh...Root function in uptake of nutrients and the effect of soil water on the transfer and distribution of NO3^--N in arable soil were studied using summer maize （Zea mays L. var. Shandan 9） as a testing crop. Results showed that root growth and water supply had a significant effect on NO3^--N transfer and made NO3^--N distributed evenly from bulk soil to rhizosphere soil. Under a natural condition with irrigation, the difference of NO3^--N concentration at different distance points from a maize plant was smaller, while obvious difference of NO3^--N concentration was observed under conditions of limited root growth space without irrigation. Whether root growth space was restricted or not, the content of soil NO3^--N decreased gradually from 10 to 0 cm from the plant, being opposite to the root absorbing area in soils. When root-grown space was limited, changes of NO3^--N concentration at different distances from a plant were similar to that of water content in tendency. Results showed that NO3^--N could be transferred as solute to plant root systems with water uptake by plants. However, the transfer and distribution of NH4^--N were not influenced by root growth and soil water supply, being different to NO3^--N.展开更多
以广西壮族自治区马山县为研究区,在野外调查、室内实验测试获取182个土壤水分含量数据的基础上,采用半方差函数和 Moran’s I 统计量对研究区域土壤水分含量的空间自相关关系、空间相关尺度和空间分布规律进行了研究。结果表明：（1）...以广西壮族自治区马山县为研究区,在野外调查、室内实验测试获取182个土壤水分含量数据的基础上,采用半方差函数和 Moran’s I 统计量对研究区域土壤水分含量的空间自相关关系、空间相关尺度和空间分布规律进行了研究。结果表明：（1）研究区域土壤水含量平均值为16.97%,受结构性因素和随机因素共同作用,土壤水分含量具有中等强度的空间异质性；（2）研究区域土壤水分含量 Moran’s I 指数为0.423,表明研究区内土壤水分含量存在空间自相关性,在0-21 km 和31-34 km 范围内土壤水分含量自相关性为正,在21.7-31 km 和34-45 km 范围内自相关性为负；（3）Lisa 聚类图表明,土壤水分含量空间聚集区和空间孤立区相伴存在,其中“高-高”空间聚集主要分布在马山县东北部,“低-低”聚集区主要分布在东南部。“低-低”聚集区和“高-低”孤立区土壤水分含量缺乏风险大。展开更多
基金the National Natural Science Foundation of China （NSFC） （30230230）.
文摘Root function in uptake of nutrients and the effect of soil water on the transfer and distribution of NO3^--N in arable soil were studied using summer maize （Zea mays L. var. Shandan 9） as a testing crop. Results showed that root growth and water supply had a significant effect on NO3^--N transfer and made NO3^--N distributed evenly from bulk soil to rhizosphere soil. Under a natural condition with irrigation, the difference of NO3^--N concentration at different distance points from a maize plant was smaller, while obvious difference of NO3^--N concentration was observed under conditions of limited root growth space without irrigation. Whether root growth space was restricted or not, the content of soil NO3^--N decreased gradually from 10 to 0 cm from the plant, being opposite to the root absorbing area in soils. When root-grown space was limited, changes of NO3^--N concentration at different distances from a plant were similar to that of water content in tendency. Results showed that NO3^--N could be transferred as solute to plant root systems with water uptake by plants. However, the transfer and distribution of NH4^--N were not influenced by root growth and soil water supply, being different to NO3^--N.
文摘以广西壮族自治区马山县为研究区,在野外调查、室内实验测试获取182个土壤水分含量数据的基础上,采用半方差函数和 Moran’s I 统计量对研究区域土壤水分含量的空间自相关关系、空间相关尺度和空间分布规律进行了研究。结果表明：（1）研究区域土壤水含量平均值为16.97%,受结构性因素和随机因素共同作用,土壤水分含量具有中等强度的空间异质性；（2）研究区域土壤水分含量 Moran’s I 指数为0.423,表明研究区内土壤水分含量存在空间自相关性,在0-21 km 和31-34 km 范围内土壤水分含量自相关性为正,在21.7-31 km 和34-45 km 范围内自相关性为负；（3）Lisa 聚类图表明,土壤水分含量空间聚集区和空间孤立区相伴存在,其中“高-高”空间聚集主要分布在马山县东北部,“低-低”聚集区主要分布在东南部。“低-低”聚集区和“高-低”孤立区土壤水分含量缺乏风险大。
