曝光臺(tái) 注意防騙 網(wǎng)曝天貓店富美金盛家居專營(yíng)店坑蒙拐騙欺詐消費(fèi)者

map (Fig. 1) was drawn to indicate the four sample ar2
eas (A , B , C , D) . Section A is the airfield area and
is mainly covered with grass. It contains five different
identified bird habitats. A construction refuse dump
full of grasses is approximately 100 m to the north of
the eastern tip of the runway. There is a sewage dis2
posal facility at the northwest tip of the parking area ,
where a sewage puddle approximately 500 m2 is formed
in spring. The floral community in Section A mainly
consists of annual grasses , like Pennisetum centrasi2
aticum , Setaria viridis , Artemisia scoparia , Potentilla
tanacetifolia , Potentilla tanacetifolia , Medicago sativ .
Wood plants , such as Picea wilsonii , Pinus tabulae2
formis , Sabina chinensis and Platycladus orientalis are
mainly distributed near the Air Traffic Control head2
quaters and Fire Department areas.
Section B is in the north of the office area and veg2
etation is mainly coniferous and broadleaf forest , includ2
ing species such as Larix principis2rupprechtii , Pinus
sylvestris var . mongolica , J uniperus rigida , Populus ×
Canadensis and Prunus davidiana . Scrub species , like
Sorbaria sorbifolia and Prunus triloba are distributed a2
mong them , of which the dominant species are Les2
pedeza davurica and Heteropappus altaicus . There is ap2
proximately 015 ha of manufactured lawn , covering 40 %
of this area. This section includes three different identi2
fied habitats.
Section C lies in a inner level area except Sections
A and B. It contains seven bird habitats. This Section
overlaps agricultural farmland and villages and is cov2
ered with artificial forest ( such as Populus simonii ,
Populus alba var . pyramidalis and pine) , a few scrub
species (such as Rosa rugosa) and agricultural crops.
The dominant plant species are Chloris virgata and
Heteropappus altaicus .
Section D is the area between inner level and cone
area . Except for large patches of village and farmland ,
water bodies , such as rivers , ponds and ditches , are
dominant in this area . The terrestrial vegetation is sim2
ilar with that in Section C , while the plants in the wet2
land are predominantly Phragmites australis , and the
plants near the water bank include Echinochloa crus2
galli , Polygonum lapathifolium and Achnatherum
splendens. Section D contains 10 different identified
bird habitats.
Fig. 1 　A sketch map of sample areas at Baita airport
11212 　Settings of sample strips 　The 25 different
bird habitats in the four sample sections (5 , 3 , 7 and
10 habitats respectively) were identified and 6 , 3 , 39
and 32 sample strips were established in the sites re2
spectively (total sample strips = 80) . The investigation
lasted three months. Investigations strip were repeated
three times a month in Sections A and B but only once
each in Sections C and D.
162 　　　　　　　動(dòng)　物　學(xué)　研　究　　　　　　　　　　　　　　　　　　　　　　　28 卷
113 　Investigation method
Birds were investigated according to the sample
strip method (Zheng , 1995) and the species and num2
ber of all birds seen within 50 m of both sides of a cen2
tral line were recorded using 10 ×50 binoculars.
Species was identified by combing the flight behavior
and birdcalls. Unidentified birds were photographed
using a digital camera and identified using A Field
Guide to the Birds of China (Yan , 1999) .
114 　Statistical method
Bird density , distribution , probability of interac2
tive encounter and the comparative importance values
(Luan et al , 2004) were measured. The potential haz2
ard to flight security was based on this evidence .
The density was calculated using D = N/ 2LW , of
which , N is the number of birds in the sample strip , L
is the length and W is the width of one side of the sam2
ple strip . The distribution coeffient (Hou et al , 2001)
was calculated according to ADC = ( n/ N + m/ M) ×
100 % , in which , n is the number of sample strips and
m is number of habitats where a bird occurs. N is the
total number of strips in the investigation and M is the
total number of vegetation types investigated. According
to variable distribution coefficients , birds are grouped
into three distribution types : wide distribution (nearly
100 %) , middle distribution (25 %- 100 %) and narrow
distribution (below 25 %) . The probability of interactive
encounter (Ding et al , 1989) was calculated according
to PIE = Σ( ni / N) ×[ ( N - ni ) / ( N - 1) ] , in which ,
ni is the number of bird i , and N is the total number
of birds. The comparative importance values expresses
　
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