黑河流域中游荒漠典型区域植被生物量及其影响因素

以黑河流域中游荒漠区地表植被和土壤水分2008—2016年长期定位监测数据为依据，深入分析了试验区植被高度、盖度、密度和土壤水分变化对植被地上生物量的影响，确定了各相关因子的贡献率，为黑河流域荒漠化区生态治理提供数据支撑。结果表明：龙首荒漠区9年间的生物量变幅85.8—214.6 g·m^-2，2015年的群落平均盖度和生物量最大，分别为33.7%和214.6 g·m^-2，群落密度对生物量的年际变化贡献大，贡献率27%，群落高度、10—20 cm层次土壤水分对生物量的年际变化贡献次之，贡献率14%；西洞荒漠区生物量变幅55.1—109.8 g·m^-2，群落盖度、植株密度和高度等生物因子对其生物量的年际变化影响较小，而0—40 cm层次土壤含水量的变化对西洞荒漠区生物量年际变化的贡献较大，为20%以上。

The characteristics of desert vegetation biomass and its influencing factors in the middle reaches of the Heihe River

Through the long-term positioning monitoring on aboveground vegetation and soil water contents of 0-40 cm layer in the middle Heihe River Basin from 2008 to 2016,we researched the effects of vegetation height,coverage,density and soil water variations on aboveground vegetation biomass in different desert areas,and confirmed contribution rates of different influencing factors to biomass.We hoped the result can provide the data support to ecological management of desertification in the region.The results showed that the interannual variations of biomass in Longshou desert area fluctuate greatly from 85.8 g·m^-2to 214.6 g·m^-2.In 2015,the coverage of plants community and biomass were the largest and reached to 33.7%and 214.6 g·m^-2,respectively.The density of community had a great contribution with a rate of 27%to interannual changes of biomass.Then those of the community height and soil water content in 10-20 cm layer were also higher and up to 14%.In Xidong desert area,the interannual variations of biomass were 55.1-109.8 g·m^-2,having small fluctuation range.The community coverage,plant density and height had little effects on the interannual variations of biomass.However,the changes of soil water contents in 0-40 cm layers contributed more than 20%rates to the changes of biomass.