CAJ | 학술논문

将黄土高原典型草原植物亚生态系分为地上活体、立枯物、凋落物和地下根系4个部分,进行放牧与围封草地植物生物量及其碳、氮、磷贮量的研究.结果表明,放牧与围封草地各组分碳、氮、磷贮量的季节动态模式与其对应生物量变化规律一致;碳、氮、磷贮量均与生物量呈极显著正相关(P<0.01),其相关系数分别为0.990,0.899和0.936(FG),0.990,0.891和0.936(GG);封育和放牧草地植物间各部分碳、氮、磷贮量差异均由各自生物量差异引起.围封草地植物总生物量和地上、地下生物量、立枯物、凋落物的量,以及碳、氮、磷贮量一般高于放牧样地(P<0.05).地上活体氮、磷贮量在其生物量最大时最高(7月),此时围封草地地上活体氮、磷贮量(1.291 8,0.083 7 g/m~2)显著低于放牧草地(1.529 7,0.100 2 g/m~2)(P<0.05).放牧草地主要通过地上幼嫩器官生物量和氮、磷含量的增加来获得较大氮磷贮量,并以此提高草地利用率.
장황토고원전형초원식물아생태계분위지상활체、립고물、조락물화지하근계4개부분,진행방목여위봉초지식물생물량급기탄、담、린저량적연구.결과표명,방목여위봉초지각조분탄、담、린저량적계절동태모식여기대응생물량변화규률일치;탄、담、린저량균여생물량정겁현저정상관(P<0.01),기상관계수분별위0.990,0.899화0.936(FG),0.990,0.891화0.936(GG);봉육화방목초지식물간각부분탄、담、린저량차이균유각자생물량차이인기.위봉초지식물총생물량화지상、지하생물량、립고물、조락물적량,이급탄、담、린저량일반고우방목양지(P<0.05).지상활체담、린저량재기생물량최대시최고(7월),차시위봉초지지상활체담、린저량(1.291 8,0.083 7 g/m~2)현저저우방목초지(1.529 7,0.100 2 g/m~2)(P<0.05).방목초지주요통과지상유눈기관생물량화담、린함량적증가래획득교대담린저량,병이차제고초지이용솔.
The plant subsystem in typical steppe grassland of the Loess Plateau was divided into four components: live shoots, standing dead matter, litter, and underground roots. The plant biomass of these four components and their C, N, and P contents were studied in grazed (GG) and fenced (FG) grasslands. The seasonal dynamics of each component biomass was correlated with their C, N and P contents both in grazed and fenced grasslands. There were significant positive correlations between plant biomass and C, N, and P contents, with correlation coefficients of 0.990, 0.899, 0.936 (FG) and 0.990, 0.891, 0.936 (GG), respectively. The differences in C, N, and P contents of each plant component were caused by the difference in plant biomass. The total biomass, aboveground and underground biomass, standing dead matter and litter, and their C, N, and P contents were significantly (P<0.05) higher in fenced grassland than those in grazed grassland. The N and P contents in live shoots were highest in July, and significantly (P<0.05) lower in fenced (1.291 8 and 0.083 7 g/m~2 for N and P respectively) than in grazed (1.529 7 and 0.100 2 g/m~2 for N and P respectively) grassland. The results indicate that the higher plant N, P storages in grazed grassland were mainly attributed to the increases of young organ biomass and their N, P contents, which further improve the utilization of grassland.