兰州大学学报(自然科学版)
蘭州大學學報(自然科學版)
란주대학학보(자연과학판)
JOURNAL OF LANZHOU UNIVERSITY(NATURAL SCIENCES)
2013年
6期
807-814,821
,共9页
张璐璐%王孝安%王海东%朱志红
張璐璐%王孝安%王海東%硃誌紅
장로로%왕효안%왕해동%주지홍
刈割%施肥%浇水%垂穗披碱草%生物量分配%可溶性糖%补偿生长
刈割%施肥%澆水%垂穗披堿草%生物量分配%可溶性糖%補償生長
예할%시비%요수%수수피감초%생물량분배%가용성당%보상생장
clipping%fertilizing%watering%Elymus nutans%biomass allocation%water-soluble carbohydrate%compensatory growth
以青藏高原东部高寒矮嵩草草甸常见种垂穗披碱草为研究对象,通过为期3年的野外控制实验,研究了生长季早期刈割(重度刈割:留茬1 cm、中度刈割:留茬3 cm及对照:不刈割)、施肥(施肥、不施肥)和浇水(浇水、不浇水)对垂穗披碱草生物量分配、根系可溶性糖质量分数及补偿生长的影响,探讨其补偿生长机制。结果表明:与不刈割相比,中度刈割后垂穗披碱草增加了生长分配,减少了繁殖分配,繁殖分配与生长分配及贮藏分配均呈显著负相关,生长分配与贮藏分配间呈显著正相关,同时根系可溶性糖质量分数随刈割强度的增加显著提高;地上生物量与地下生物量在刈割后均发生低补偿,且二者之间存在着正相关关系,植物根系可溶性糖贮藏量在刈割后发生了超补偿;施肥消除了刈割后垂穗披碱草生物量分配与不刈割处理间的差异,并显著增加了垂穗披碱草的补偿地上生物量,浇水对多数测量指标的影响不显著,只显著增加了垂穗披碱草根系可溶性糖质量分数。说明刈割后植物可以通过增加其生物量分配和营养物质贮藏的可塑性来适应恶劣的生存环境,实现补偿性再生长,同时会以牺牲一部分繁殖分配为代价,施肥能够减小刈割带来的负面影响,提高垂穗披碱草的补偿生长能力,但却依然不足以引起植物生物量发生超补偿效应,故应严格控制刈割强度。
以青藏高原東部高寒矮嵩草草甸常見種垂穗披堿草為研究對象,通過為期3年的野外控製實驗,研究瞭生長季早期刈割(重度刈割:留茬1 cm、中度刈割:留茬3 cm及對照:不刈割)、施肥(施肥、不施肥)和澆水(澆水、不澆水)對垂穗披堿草生物量分配、根繫可溶性糖質量分數及補償生長的影響,探討其補償生長機製。結果錶明:與不刈割相比,中度刈割後垂穗披堿草增加瞭生長分配,減少瞭繁殖分配,繁殖分配與生長分配及貯藏分配均呈顯著負相關,生長分配與貯藏分配間呈顯著正相關,同時根繫可溶性糖質量分數隨刈割彊度的增加顯著提高;地上生物量與地下生物量在刈割後均髮生低補償,且二者之間存在著正相關關繫,植物根繫可溶性糖貯藏量在刈割後髮生瞭超補償;施肥消除瞭刈割後垂穗披堿草生物量分配與不刈割處理間的差異,併顯著增加瞭垂穗披堿草的補償地上生物量,澆水對多數測量指標的影響不顯著,隻顯著增加瞭垂穗披堿草根繫可溶性糖質量分數。說明刈割後植物可以通過增加其生物量分配和營養物質貯藏的可塑性來適應噁劣的生存環境,實現補償性再生長,同時會以犧牲一部分繁殖分配為代價,施肥能夠減小刈割帶來的負麵影響,提高垂穗披堿草的補償生長能力,但卻依然不足以引起植物生物量髮生超補償效應,故應嚴格控製刈割彊度。
이청장고원동부고한왜숭초초전상견충수수피감초위연구대상,통과위기3년적야외공제실험,연구료생장계조기예할(중도예할:류치1 cm、중도예할:류치3 cm급대조:불예할)、시비(시비、불시비)화요수(요수、불요수)대수수피감초생물량분배、근계가용성당질량분수급보상생장적영향,탐토기보상생장궤제。결과표명:여불예할상비,중도예할후수수피감초증가료생장분배,감소료번식분배,번식분배여생장분배급저장분배균정현저부상관,생장분배여저장분배간정현저정상관,동시근계가용성당질량분수수예할강도적증가현저제고;지상생물량여지하생물량재예할후균발생저보상,차이자지간존재착정상관관계,식물근계가용성당저장량재예할후발생료초보상;시비소제료예할후수수피감초생물량분배여불예할처리간적차이,병현저증가료수수피감초적보상지상생물량,요수대다수측량지표적영향불현저,지현저증가료수수피감초근계가용성당질량분수。설명예할후식물가이통과증가기생물량분배화영양물질저장적가소성래괄응악렬적생존배경,실현보상성재생장,동시회이희생일부분번식분배위대개,시비능구감소예할대래적부면영향,제고수수피감초적보상생장능력,단각의연불족이인기식물생물량발생초보상효응,고응엄격공제예할강도。
A 3-year field manipulative experiment was conducted on Elymus nutans in a Kobresia humilis meadow of Qinghai-Tibet Plateau to study the effects of clipping (heavy clipped: stubbled 1 cm;medium clipped:stubbled 3 cm and control: unclipped), fertilizing (fertilized, unfertilized) and watering (watered, unwatered) on the biomass allocation, water-soluble carbohydrate content and compensatory growth at the early time of growing season, aiming at a discussion of the compensatory mechanism of Elymus nutans. The results showed that the growth allocation was increased while reproduction allocation was reduced after medium clipped state compared with the unclipped state, the reproductive allocation had significantly negative correlations with the growth allocation and the storage allocation, and the growth allocation had a significantly positive correlation with the storage allocation. Besides, with the increase of clipping intensity, the water-soluble carbohydrate content of roots was significantly increased. The aboveground and underground biomass occurred as under-compensated, while the water-soluble carbohydrate storage of roots occurred as over-compensated after clipping, and the compensation of aboveground biomass had a significantly positive correlation with the compensation of underground biomass. Fertilization eliminated the differences of biomass allocation between clipped and unclipped states, and increased the compensation of aboveground biomass. The effect of watering was not obvious on most measurable indicators, while only increased the water-soluble carbohydrate content of roots.The results above indicated that the adaptation abilities to the complex conditions of existence were inproved by means of increasing biomass allocation and storing nutrition plasticity, and the compensatory growth of plants would sacrifice parts of their reproduction allocation. Fertilization could reduce the negative effects of clipping, enhance the compensation ability of plants, but it was not enough to cause over-compensation of biomass. Therefore, the clipping intensity should be strictly controlled.