江西寻乌样区两栖动物多样性的时空格局分析

Analyses on Spatial-temporal Distribution Patterns of the Amphibian Diversity in Xunwu Sample Zones, Jiangxi Province

江西省寻乌县位于赣南赣州市东南部,闽、赣、粤三省交界处,因独特的地理位置、温暖湿润的亚热带季风气候、发达的水系河网,被全国两栖动物多样性观测网络列为观测样区。根据地形、地貌和生境,选择河流、池塘、人工水渠设置12条调查样线,于2018年4月底、6月中旬和7月底进行观测。此次调查发现两栖动物755只,隶属于1目5科10属10种,黑眶蟾蜍(Duttaphrynus melanostictus)、沼水蛙(Boulengerana guentheri)和泽陆蛙(Fejervarya multistriata)的优势度指数(P_(i))均大于0.1,为调查期间优势种,被IUCN列为濒危(EN)等级的虎纹蛙(Hoplobatrachus chinensis)共调查到15只(P_(i)>0.01),其优势度高于长肢林蛙(Rana longicrus)、大树蛙(Rhacophorus dennysi)和饰纹姬蛙(Microhyla fissipes)(P_(i)<0.01)。区系组成表现为典型的华中华南区,而广布种仅为黑斑侧褶蛙(Pelophylax nigromaculatus),生态型以陆栖静水型和静水型为主,流水型和树栖型各有1种。两栖动物丰富度和相对多度在4月达最高,物种多样性时间格局受繁殖季节和繁殖期时长的影响,此次观测物种大部分为春季繁殖,而繁殖期集中于夏季的弹琴蛙(Nidirana adenopleura)和黄岗臭蛙(Odorrana huangangensis)仅在7月被观测到。空间格局分析显示,河流生境样线数量多,环境异质性高,物种丰富度高;池塘生境相对稳定,虽然样线数仅占调查总数的25%,相对多度则占观测总数的51.4%,人工水渠物种丰富度和相对多度最低。由于此次调查缺乏长期观测数据,且调查时间和空间未覆盖所有季节和生境,导致物种多样性低于江西省已有记录,有必要进行长期的数据积累和全面观测。

Xunwu County is located in southeastern Ganzhou City,Jiangxi Province,and at the junction of Fujian,Jiangxi,and Guangdong Provinces.Due to the unique geographical location,warm and humid subtropical monsoon climate,and developed river networks,Xunwu County has been listed as the observation region by the National Amphibian Diversity Observation Network.According to the topography,landform and habitat,12 survey lines were set up for rivers,ponds and artificial canals,and observations were conducted in Late April,Mid-June and Late July,2018.A total of 755 amphibian individuals were found and they belong to one order,5 families,10 genera and 10 species.The dominance index(P_(i))of Duttaphrynus melanostictus,Boulengerana guentheri,Fejervarya multistriata was greater than 0.1,and they were the dominant species during the surveys.Fifteen individuals of Hoplobatrachus chinensis,listed as endangered species(EN)by IUCN,were found and its dominance index(P_(i)>0.01)was higher than that of Rana longicrus,Rhacophorus dennysi and Microhyla fissipes(P_(i)<0.01).The fauna composition of amphibians in Xunwu belong to Southern China fauna,and only Pelophylax nigromaculatus is widely distributed.Most species were terrestrial aquatic and still water types,whereas only one flow type and one arboreal type species were found.The richness and relative abundance reached the highest in April,and the temporal pattern of the species diversity was affected by the breeding season and the length of the breeding period.Most of the observed species reproduced in spring,whereas Nidirana adenopleura and Odorrana huangangensis reproduced mainly in summer which were only observed in July.The spatial patterns show that the river habitat has more sample lines,higher environmental heterogeneity,and the highest species richness.The pond habitat was relatively stable and the relative abundance reached to 51.4%of the total in this survey,although the number of survey lines accounts for only 25%of the total numbers of this survey.The richness and relative abundance of artificial canals were the lowest.Due to only one year data of 2018 was obtained,there is a lack of long-term observations,and the cover of the season and habitats in this survey is incomplete,and the species diversity revealed is lower than that recorded in Jiangxi province.Long-term data accumulation and comprehensive observations should be conducted to address the issues of diversity,population size and threatened factors of amphibians and to provide scientific basis for the ecological protection and restoration of mountains,lakes,forests and grasses.