CAJ | 학술논문

为了揭示草地生态系统的现存生物量随时间的变化规律与气候条件和人为干扰(放牧压,施肥量等)之间的关系,从1974年开始至1994年,每年的4月至11月,在位于日本中部那须地区的国立草地研究所内的人造围栏放牧草场进行了放牧试验.结果表明,在1974至1994年的21年间,在不同放牧处理(放牧压分别为轻度和重度/施肥分少量和大量)的条件下,地上现存生物量的季节变化非常明显,其变化范围为:150～380 g DW m-2.用4次方多项式检验表明牧草成长模式呈双峰曲线,每一年中不同放牧条件下地上现存生物量的最大值都出现在6月份左右,第二个峰值出现在9,10月份.复合回归分析的结果得出了体现现存生物量和气温,放牧压(或施肥量)之间的定量关系的多项回归方程式.协方差分析结果表明放牧压力,施肥量以及季节和年度的变化,以及他们之间的相互作用对现存生物量有着显著影响 (P<0.05) 或极显著影响(P<0.01).本研究表明在现存放牧强度下不会对地上生物量造成毁灭性的影响,而是在其承受范围之内.
위료게시초지생태계통적현존생물량수시간적변화규률여기후조건화인위간우(방목압,시비량등)지간적관계,종1974년개시지1994년,매년적4월지11월,재위우일본중부나수지구적국립초지연구소내적인조위란방목초장진행료방목시험.결과표명,재1974지1994년적21년간,재불동방목처리(방목압분별위경도화중도/시비분소량화대량)적조건하,지상현존생물량적계절변화비상명현,기변화범위위:150～380 g DW m-2.용4차방다항식검험표명목초성장모식정쌍봉곡선,매일년중불동방목조건하지상현존생물량적최대치도출현재6월빈좌우,제이개봉치출현재9,10월빈.복합회귀분석적결과득출료체현현존생물량화기온,방목압(혹시비량)지간적정량관계적다항회귀방정식.협방차분석결과표명방목압력,시비량이급계절화년도적변화,이급타문지간적상호작용대현존생물량유착현저영향 (P<0.05) 혹겁현저영향(P<0.01).본연구표명재현존방목강도하불회대지상생물량조성훼멸성적영향,이시재기승수범위지내.
In order to understand the temporal changes of biomass in grassland ecosystem, and to clarify the relation between these changes and climatic factors and artificial disturbance, a grazing trail was carried out during a 21-year period from 1974 to 1994 at a sown grassland of the National Grassland Research Institute, located in Nishinasuno, the central area of Japan. The data sets of biomass for each month (from April to November) in the 21-year period were analyzed. It showed aboveground biomass ranged from 150 to 380 g DW m-2 from 1974 with large seasonal variation under the different grazing treatments,high or low grazing intensity/ high or low nitrogen application. A fourth-order polynomial in the ANOVA indicated that the seasonal changes in aboveground biomass tended to show a growth pattern with two peaks, which appeared in early summer and autumn for each of the treatment in all years. The result of a multiple regression analysis clarified the relation between aboveground biomass and meteorological conditions, and the result of an analysis of variance (ANOVA) showed aboveground biomass had significant differences (P<0.05) even more significant (P<0.01) with the effects of grazing intensity, nitrogen application,and the seasonal and annual factors.After 21 years grazing, aboveground biomass had no tendency to decrease by either high or low grazing intensity.