农业工程学报
農業工程學報
농업공정학보
2010年
2期
82-88
,共7页
土壤%质地%土壤水分%有效性%作物%生长指标%气体交换指标%生物量指标
土壤%質地%土壤水分%有效性%作物%生長指標%氣體交換指標%生物量指標
토양%질지%토양수분%유효성%작물%생장지표%기체교환지표%생물량지표
soils%textures%soil moisture%availability%crops%growth indices%gas exchange indices%biomass indices
为确定土壤质地对玉米不同生理指标水分有效性的影响,该文利用3种土壤(重壤土、中壤土和砂壤土)的盆栽控水试验和1种土壤(重壤土)的田间小区控水试验,研究了玉米不同生理指标随相对土壤含水率(土壤含水率占田间持水率的比)的动态变化.结果表明:3种土壤中各生理指标相对值在相对土壤含水率降低到土壤水分阈值之前保持不变,低于此阈值时随相对含水率的进一步降低而线性降低,且均可用分段函数来拟合(R~2=0.824~0.999).土壤水分有效性大小排序为:砂壤土>中壤土>重壤土,而且瞬时生理指标的土壤水分阈值低于日变化和整个试验阶段的累积指标.因此土壤质地和不同生理指标的时间尺度都会影响玉米生理指标对土壤水分有效性的响应.
為確定土壤質地對玉米不同生理指標水分有效性的影響,該文利用3種土壤(重壤土、中壤土和砂壤土)的盆栽控水試驗和1種土壤(重壤土)的田間小區控水試驗,研究瞭玉米不同生理指標隨相對土壤含水率(土壤含水率佔田間持水率的比)的動態變化.結果錶明:3種土壤中各生理指標相對值在相對土壤含水率降低到土壤水分閾值之前保持不變,低于此閾值時隨相對含水率的進一步降低而線性降低,且均可用分段函數來擬閤(R~2=0.824~0.999).土壤水分有效性大小排序為:砂壤土>中壤土>重壤土,而且瞬時生理指標的土壤水分閾值低于日變化和整箇試驗階段的纍積指標.因此土壤質地和不同生理指標的時間呎度都會影響玉米生理指標對土壤水分有效性的響應.
위학정토양질지대옥미불동생리지표수분유효성적영향,해문이용3충토양(중양토、중양토화사양토)적분재공수시험화1충토양(중양토)적전간소구공수시험,연구료옥미불동생리지표수상대토양함수솔(토양함수솔점전간지수솔적비)적동태변화.결과표명:3충토양중각생리지표상대치재상대토양함수솔강저도토양수분역치지전보지불변,저우차역치시수상대함수솔적진일보강저이선성강저,차균가용분단함수래의합(R~2=0.824~0.999).토양수분유효성대소배서위:사양토>중양토>중양토,이차순시생리지표적토양수분역치저우일변화화정개시험계단적루적지표.인차토양질지화불동생리지표적시간척도도회영향옥미생리지표대토양수분유효성적향응.
For estimating the influence of soil texture on soil water availability for different maize (Zea mays L.) physiological indices, maize plants were grown in pot experiments using three soil textural types (heavy loam, medium loam and sandy loam) and a plot experiment using one soil (heavy loam) under different water regimes. The changes of different maize physiological indices in response to the changes in relative soil water content (soil water content dividing by the field capacity) was studied. Results showed that the soil water availability on various physiological indices in the three textural types of soil remained constant until soil water content decreased below the threshold value and then declined linearly with further soil water depletion. A linear-plateau model well represented the relationships between each relative plant physiological index and the relative soil water content with an R~2 value in the range of 0.824-0.999. Soil water availability declined with soil texture in the order: sandy loam > loam > heavy loam. The threshold values for physiological indices at the transient scale were lower than those for the indices at the daily and seasonal scales. Therefore, the responses to soil water availability of different maize physiological indices were found to be affected by soil texture and by the time scale over which the various indicators were determined.