四川农业大学学报
四川農業大學學報
사천농업대학학보
JOURNAL OF SICHUAN AGRICULTURAL UNIVERSITY
2014年
4期
355-361
,共7页
民勤%绿洲荒漠过渡带%群落特征%重要值%物种多样性
民勤%綠洲荒漠過渡帶%群落特徵%重要值%物種多樣性
민근%록주황막과도대%군락특정%중요치%물충다양성
Minqin%oasis-desert ecotone%community characteristics%important value%species diversity
【目的】以民勤绿洲荒漠过渡带为研究对象，沿绿洲向荒漠演变方向，测定和分析不同区段各物种在群落组成中的地位和作用，以期为该区域荒漠化防治和生态恢复提供依据。【方法】从绿洲外围边界开始，沿绿洲至荒漠（东南－西北）方向，采用样线调查方法，测计区域内不同区段群落中植物种类、数量、频度、冠幅、高度和地径等，计算获得各物种重要值及其多样性指数。【结果】研究区不同区段共有23种植物，隶属于10科23属，其中灌木6科8种，草本8科15种；灌木层重要值最大的为Ⅲ-灌丛沙包区唐古特白刺，达到153．48％，草本层则以藜科占据主导地位；基于重要值计算得到的不同区段灌木层和草本层的多样性均无明显差异，灌木层和草本层的H′、D和Dmc随着绿洲向荒漠过渡均逐渐减小，Jsw值由于唐古特白刺出现单优现象呈现波动变化。【结论】研究区内群落灌木层更新和生长相对稳定，但群落整体结构简单，物种多样性低，克隆植物的有效生长在一定程度上加速了物种多样性的简单化。
【目的】以民勤綠洲荒漠過渡帶為研究對象，沿綠洲嚮荒漠縯變方嚮，測定和分析不同區段各物種在群落組成中的地位和作用，以期為該區域荒漠化防治和生態恢複提供依據。【方法】從綠洲外圍邊界開始，沿綠洲至荒漠（東南－西北）方嚮，採用樣線調查方法，測計區域內不同區段群落中植物種類、數量、頻度、冠幅、高度和地徑等，計算穫得各物種重要值及其多樣性指數。【結果】研究區不同區段共有23種植物，隸屬于10科23屬，其中灌木6科8種，草本8科15種；灌木層重要值最大的為Ⅲ-灌叢沙包區唐古特白刺，達到153．48％，草本層則以藜科佔據主導地位；基于重要值計算得到的不同區段灌木層和草本層的多樣性均無明顯差異，灌木層和草本層的H′、D和Dmc隨著綠洲嚮荒漠過渡均逐漸減小，Jsw值由于唐古特白刺齣現單優現象呈現波動變化。【結論】研究區內群落灌木層更新和生長相對穩定，但群落整體結構簡單，物種多樣性低，剋隆植物的有效生長在一定程度上加速瞭物種多樣性的簡單化。
【목적】이민근록주황막과도대위연구대상，연록주향황막연변방향，측정화분석불동구단각물충재군락조성중적지위화작용，이기위해구역황막화방치화생태회복제공의거。【방법】종록주외위변계개시，연록주지황막（동남－서북）방향，채용양선조사방법，측계구역내불동구단군락중식물충류、수량、빈도、관폭、고도화지경등，계산획득각물충중요치급기다양성지수。【결과】연구구불동구단공유23충식물，대속우10과23속，기중관목6과8충，초본8과15충；관목층중요치최대적위Ⅲ-관총사포구당고특백자，체도153．48％，초본층칙이려과점거주도지위；기우중요치계산득도적불동구단관목층화초본층적다양성균무명현차이，관목층화초본층적H′、D화Dmc수착록주향황막과도균축점감소，Jsw치유우당고특백자출현단우현상정현파동변화。【결론】연구구내군락관목층경신화생장상대은정，단군락정체결구간단，물충다양성저，극륭식물적유효생장재일정정도상가속료물충다양성적간단화。
Obj ective]Along the evolution direction from oasis to desert in the Minqin oasis-desert ecotone,the position and function of each species in the community composition among different segments were investigated and analyzed.The results could provide the basis for the regional de-sertification control and ecological restoration.[Method]From oasis to desert (northwest-south-east),line transect method was used to investigate the vegetation types,volume,crown breadth, height and ground diameter,etc.The important value and species diversity index were calculated.[Results]There were 23 species in different sections in the area,belonging to 10 families and 23 genera.There were 6 families 8 species in shrubs and 8 families 15 species in herbs.The largest important value of shrub (153. 48%)was the Nitrariatangutorum in the sandbags area.The Chenopodiaceaedominated herb layer.There were no obvious differences in the diversity of shrub and herb based on important value in the different stages.The H′,D and Dmc of shrub and herb decreased from oasis to desert transition.The Jsw value fluctuated due to individual advantage of Nitrariatangutorum.[Conclusion]In the study area,shrubs regeneration and growth was rela-tively stable.However,community structure was simple and species diversity was low.The growth of clonal plants,to some extent,accelerated the simplification of species diversity.
