摘要
为揭示小尺度植被与土壤相互作用在维持草地稳定性中的作用,研究以放牧干扰下退化短花针茅草地为对象,以临近的围栏封育草地为对照(CK),对比研究了放牧干扰下短花针茅植丛边缘(丛内)以及丛外裸斑(丛外)处表层土壤颗粒组分与养分的小尺度分布规律,及其相关关系在空间上的变化。结果表明:(1)整体而言,黏粒(<2μm)与砂粒(50～2 000μm)的分布规律相反,呈显著负相关关系,围封使土壤黏粒含量显著提高,砂粒和粉粒(2～50μm)显著降低(p<0.05);有机碳(SOC)与黏粒的分布变化规律一致,全氮(TN)无显著变化;植丛内外无显著区别(p>0.05)。(2) 2 cm间隔精细分层下,围封使任意土层土壤黏粒和砂粒分别显著提高和显著降低,0—8 cm土层的粉粒显著降低(p<0.05);SOC 2—8 cm和12—14 cm土层显著提高,TN无显著变化,但植丛的存在显著提高了围封区植丛内0—4 cm土层SOC含量(p<0.05)。(3)随土层垂直变化,围封区黏粒含量逐步提高,粉粒和砂粒逐步降低;SOC和TN无显著变化(p>0.05)。放牧区黏粒12—14 cm土层显著增高,粉粒逐步递减,砂粒先增高后降低(p<0.05);SOC表聚性分布,TN植丛内"V"型分布中间土层降低,丛外无显著变化(p>0.05)。围封区颗粒组分间的相关关系变化基本稳定,放牧区部分土层显著相关性丧失;围封区颗粒组分与SOC,TN无显著相关(p>0.05),放牧区则与SOC的显著相关集中在10—14 cm土层,与TN集中在8—14 cm土层。总之,放牧干扰不仅导致了土壤质地和养分水平的显著下降,同时也改变了土壤内部不同理化指标间的相互关系及其分布格局,但是植丛的存在并未显著改善丛下土壤质地和养分状况。
In order to reveal the role of small-scale plants-soil interactions in maintaining grassland stablity, we used the grazing degraded Stipa breviflora grassland as the site and the adjacent fenced grassland as the control(CK) to compare and analyze the spatial distribution of particle sizes and nutrient characteristics of surface soil in the small-scale on the plexus edge(inside of the plant community) and the bare spot(outside of the plant community) of Stipa breviflora under the grazing disturbance, and spatial changes in their correlation. The results showed that:(1) in general, the distribution pattern of clay(<2 μm) was opposite to that of and sand(50~2 000 μm), showing a significantly negative correlation between clay and sand, and enclosure significantly increased soil clay content, decreased and sand content and silt content(2~50 μm) significantly(p<0.05);the distribution of organic carbon(SOC) and clay was consistent, total nitrogen(TN) did not significantly change;and there is no significant difference between the inside and outside of the plant community;(2) enclosure significantly increased and significantly reduced soil clay and sand in any soil layer divided by 2 cm interval;the silt content of 0—8 cm soil layer was significantly low(p<0.05);the SOC in 2—8 cm and 12—14 cm soil layers were significantly improved, and TN had no significant change, but the presence of planting clumps significantly improved SOC content of 0—4 cm soil layer(p<0.05) inside of the enclosed area;(3) with the vertical change of soil layer, the content of clay in the enclosed area gradually increased, and the contents of silt and sand gradually decreased;SOC and TN did not change significantly(p>0.05);the content of caly increased significantly, and the content of silt gradually decreased in 12—14 cm soil layer in the grazing area, the content of sand increased first and then decreased(p<0.05). The SOC accumulation in the surface layer of soil, and the contents of TN presented the V-shape distribution, and was lowe
作者
苗翻
杨新国
古君龙
杨东东
MIAO Fan;YANG Xinguo;GU Junlong;YANG Dongdong(Key Laboratory for Restoration and Reconstruction of Degraded Ecosystem in North-Western China,Ministry of Education,Yinchuan 750021,China;Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration of Northwestern China,Ningxia University,Yinchuan 750021,China;Union Research Center for Ecological and Exploitation of Biological Resources in Western China,Ningxia University,Yinchuan 750021,China)
出处
《水土保持研究》
CSCD
北大核心
2019年第3期49-57,共9页
Research of Soil and Water Conservation
基金
国家自然科学基金(31460161)
宁夏大学西部一流学科建设项目(NXYLXK2017B06)
宁夏大学西部一流大学建设项目(GZXM2017001)
关键词
空间分布
植丛边缘
丛外裸斑
土壤性质
短花针茅
放牧干扰
spatial distribution
plexus edge
bare spot outside plants
soil properties
Stipa breviflora
grazing interference
