卧龙及草坡自然保护区大熊猫的种群与保护

Population and Conservation of Giant Pandas In Wolong and Caopo Nature Reserves

卧龙和草坡自然保护区以保护大熊猫及其生态系统为主,面积3224km2,为中国大熊猫分布区最大的保护区。自1974年以来,我们经过多次调查,其栖息地由约2500km2缩减到现今约800km2。大熊猫在该地所选择的最适生境在海拔2800～3100m一带的三、四级夷平地带,面积约4×104hm2。大熊猫的种群数量,据1974年调查有195只(其中卧龙为145只),1983年冷箭竹大面积开花后种群有所下降,而上世纪90年代以后有所恢复,现在约有150只。在保护对策上,应在4个隔离种群间退耕还林,控制交通流量和禁止夜间通行,扩大保护范围到毗邻的县,对最适的栖息地实行绝对保护,并控制旅游规模及旅客流量。

Since 1974, many investigations on the population and conservation of giant pandas have been carried out in Wolong and Caopo Nature Reserves.The two reserves are located in the eastern foot of Qionglai Mountains, which is the central zone of the five mountains where Chinese giant pandas live.The area is 3 224 km^2, constituting 75.73% of the total area of the six reserves in Qionglai Mountains and 21.41% of 35 reserves in China. Located in the high mountain and deep valley belt which transits from Sichuan Basin to Qinghai-Tibet Plateau, there are advantageous natural conditions in the two reserves.Their faunas are old and complex, and their biodiversity also is extremely abundant.According to the relevant statistics, there are over 400 species of higher plants in the two reserves and 481 terrestrial vertebrate, species that constitutes 45.38% in Sichuan.Besides the giant panda,these two reserves are also the distributive central belt for -Rhinopithecus roxellana,Budorcas taxicolor-,and so on,which are rare and endangered animals.Furthermore,there are 100 Chinese native terrestrial vertebrate in the two reserves constituting 37% of that in Sichuan.As to the habitat selection of the giant pandas, the most desirable habitats lie in the third or fourth plane with 3×10~4 hm^2 at an altitude of 2 8003100m,wheretherearegentlelandforms,prosperousvegetations, green bamboos and abundant water sources.The more desirable habitats selected by part of the giant pandas in the summer with 2×10~4 hm^2 are located at an altitude of 3 100-3 600 m,where slopes are steeper and vegetations are lower with cold winter and cool summer.The habitats with worse quality are located at an altitude of 2 100-2 500 m,where the vegetation is needle-and-broad-leaf-mixed forests and has been relatively destroyed severely.As leaves on many trees fall, sunshine is reinforced and there is little snow on the ground.Some panda individuals may utilize this sort of habitats in the winter,or they eat bamboo shoot there in the summer.It covers 8 000 hm^2.The last sort of habitats with the worst quality are below the altitude of 2 100 m,down to valleys,where the gentle slopes have been turned into croplands and the forests only exist in steep valleys.A few pandas go down there to havebamboo leaves and drink and the area of that is 12 000 hm^2 or so.According to the investigation in 1974,there are 195 giant pandas in those two reserves with 145 of them.Sine -Bashania fangiana- bloomed and died off widely in 1983,the number of panda population decreased and only about 100 pandas survived,which was based on incomplete survey after the calamity.However,it should be mentioned that several graduate students,who studied at the Nanchong Teachers College made similar survey and their results indicated more than 100 pandas survived in the two reserves.In 1998, another investigation was carried out, indicating over 150 pandas living there. That indicated the number of the panda population had been increased gradually. According to the life table, which is based on the age determination of incisor sections of the skulls collected in the field, the net reproduction rate (R0) is 1.067 2 and the mean generation time is 11.679 year.The viability of Wuyipeng giant panda population has also been analyzed.Its results also show the net reproduction rate R_0 >1.There are significant differences for the genetic diversity of giant panda among the five mountains, and Qionglai Mountains takes the first place. Based all above researches, the local panda population may gradually increase at present. As to conservative strategies, croplands should be returned back to original forests to make it possible for the separated local population to diffuse and migrate one another. The rate of traffic flow should also be limited on the road, which crosses transversely Wolong Nature Reserve, especially prohibiting car driving at night. The absolute sealed of the conservationshouldbe in place to protect in the most desirable habitats for giant pandas, and the area for traveling