漫川漫岗黑土区作物根层土壤含水量受植被覆盖、地形、土壤温度、降雨等多因素的影响,是农业生产和农田管理的关键要素。以友谊农场两个不同坡度的典型耕地地块(平耕地与等高种植坡耕地)为研究对象,利用Landsat 8遥感数据结合气象数据...漫川漫岗黑土区作物根层土壤含水量受植被覆盖、地形、土壤温度、降雨等多因素的影响,是农业生产和农田管理的关键要素。以友谊农场两个不同坡度的典型耕地地块(平耕地与等高种植坡耕地)为研究对象,利用Landsat 8遥感数据结合气象数据等驱动SEBAL(Surface Energy Balance Algorithm for Land)模型估算根层土壤含水量,利用地面实测数据对估算结果展开验证。在此基础上分析根层土壤含水量空间分布的影响因素。结果表明:①SEBAL模型估算的根层土壤含水量6月27日决定系数R2为0.85,7月13日决定系数R2为0.68,且7月13日根层土壤含水量明显高于6月27日;平耕地6月27日决定系数R2为0.65,7月13日为0.84;等高种植坡耕地6月27日决定系数为0.64,7月13日为0.50。②地块不同导致作物根层土壤含水量影响因素也不同,平耕地主要影响因素为坡度、植被覆盖度和土壤温度;等高种植坡耕地为高程和土壤温度。使用SEBAL模型可以较为快速准确地估算根层土壤含水量,研究结果对于黑土区耕地的水分管理、农业灌溉及水分运移研究具有重要意义。展开更多
A study was carried out to investigate changes in the soil plant-available P,the P nutrition and the growth of Pinus radiata seedlings grown in association with understory,broom（Cytisus scoparius L.） or ryegrass（Lo...A study was carried out to investigate changes in the soil plant-available P,the P nutrition and the growth of Pinus radiata seedlings grown in association with understory,broom（Cytisus scoparius L.） or ryegrass（Lolium multiflorum） on Orthic Allophanic Soil,following the application of three rates of triple superphosphate（TSP）（0,50,and 100 mg·kg^-1P） under a glasshouse condition.The application of P fertilizer enhanced P availability in the rhizospheric of radiata seedlings and the bulk soils in a P-deficient site.P availability in the rhizospheric soils of ryegrass and broom,grown in association with radiata,were also increased by the presence of radiata roots.P concentrations in new shoot needles,old shoot needles,stem and roots of radiata pine increased with increase rates of TSP application,but the effects of ryegrass and broom on P nutrition of radiata seedlings depended on the soil P status.In the absence of P fertilizer addition（control treatment）,P concentrations in new shoot needles,old shoot needles,stem,and roots of radiata grown in association with broom were higher than those with ryegrass,whereas,when P fertilizer was added（50 and 100 mg·kg^-1） the P concentration was lower.This is probably related to the growth of broom that may have removed much of the plant-available P in the soil as indicated by the consistently lower Bray-2 P concentration in the rhizosphere soil of radiata in association with broom than that in the rhizosphere soil of radiata in association with grass at the two high P rates.Furthermore,in the high P fertile soil（application rate of 100 mg·kg^-1）,the dry matter yield of radiata was lower when it was grown with broom than with ryegrass.This result suggests that in moderate to high P fertile soils,P.radiata seedlings grow better with ryegrass than with broom,because broom grows vigorously in high P fertile soil and competes with P.radiata for P and perhaps for other nutrients as well.展开更多
文摘漫川漫岗黑土区作物根层土壤含水量受植被覆盖、地形、土壤温度、降雨等多因素的影响,是农业生产和农田管理的关键要素。以友谊农场两个不同坡度的典型耕地地块(平耕地与等高种植坡耕地)为研究对象,利用Landsat 8遥感数据结合气象数据等驱动SEBAL(Surface Energy Balance Algorithm for Land)模型估算根层土壤含水量,利用地面实测数据对估算结果展开验证。在此基础上分析根层土壤含水量空间分布的影响因素。结果表明:①SEBAL模型估算的根层土壤含水量6月27日决定系数R2为0.85,7月13日决定系数R2为0.68,且7月13日根层土壤含水量明显高于6月27日;平耕地6月27日决定系数R2为0.65,7月13日为0.84;等高种植坡耕地6月27日决定系数为0.64,7月13日为0.50。②地块不同导致作物根层土壤含水量影响因素也不同,平耕地主要影响因素为坡度、植被覆盖度和土壤温度;等高种植坡耕地为高程和土壤温度。使用SEBAL模型可以较为快速准确地估算根层土壤含水量,研究结果对于黑土区耕地的水分管理、农业灌溉及水分运移研究具有重要意义。
基金supported by Massey University and the Centre for Sustainable Forest Management at Forest Research Institute, New Zealand
文摘A study was carried out to investigate changes in the soil plant-available P,the P nutrition and the growth of Pinus radiata seedlings grown in association with understory,broom（Cytisus scoparius L.） or ryegrass（Lolium multiflorum） on Orthic Allophanic Soil,following the application of three rates of triple superphosphate（TSP）（0,50,and 100 mg·kg^-1P） under a glasshouse condition.The application of P fertilizer enhanced P availability in the rhizospheric of radiata seedlings and the bulk soils in a P-deficient site.P availability in the rhizospheric soils of ryegrass and broom,grown in association with radiata,were also increased by the presence of radiata roots.P concentrations in new shoot needles,old shoot needles,stem and roots of radiata pine increased with increase rates of TSP application,but the effects of ryegrass and broom on P nutrition of radiata seedlings depended on the soil P status.In the absence of P fertilizer addition（control treatment）,P concentrations in new shoot needles,old shoot needles,stem,and roots of radiata grown in association with broom were higher than those with ryegrass,whereas,when P fertilizer was added（50 and 100 mg·kg^-1） the P concentration was lower.This is probably related to the growth of broom that may have removed much of the plant-available P in the soil as indicated by the consistently lower Bray-2 P concentration in the rhizosphere soil of radiata in association with broom than that in the rhizosphere soil of radiata in association with grass at the two high P rates.Furthermore,in the high P fertile soil（application rate of 100 mg·kg^-1）,the dry matter yield of radiata was lower when it was grown with broom than with ryegrass.This result suggests that in moderate to high P fertile soils,P.radiata seedlings grow better with ryegrass than with broom,because broom grows vigorously in high P fertile soil and competes with P.radiata for P and perhaps for other nutrients as well.
