《自然》[Nature]13年2月7日出版pdf全文

nero1981

+ P" T5 \/ w7 d( h5 k" Q; I

* o0 J6 E3 u+ J* K" i) P
0 F/ L4 y( `. P2 N/ r8 IAbout the
& B) k: I+ {3 z# p. A7 bCover
: d: o& ~  ^  s- \$ y/ A5 `3 tStretches of oak savanna 8 K7 R+ _/ u- g. b8 ^4 Y9 z
in the Pacific Northwest of North America have been subject to fire-prevention
+ q( t) U4 `& m3 [: P! ^# n& Qmeasures since the mid-nineteenth century. The resulting grassland has lost # y' i; ^' m; a) J' J/ U! b  V8 T* ?
plant species but achieves stable high-yield annual production — rather like a & h) N$ |7 h: ^( r5 v3 g- O
high-yield agricultural system — and remains resilient to invasive species and
. J! ^* X$ Y7 C! wclimate fluctuation. A long-term study in which + q& _3 {) ?' x) d" p
selected grassland plots were periodically burned and allowed to recover now 8 q  k$ i: X) M
demonstrates the critical value of biodiversity when ecosystems experience ' D& O2 M1 C( `$ b+ U/ C
disturbance. Grasslands were able to recover from burning only in areas that had
) T! t' Y( R/ J8 @! _' ?+ aa relatively high diversity of native plants. This work demonstrates how
+ M# q. ^+ X) Q, hpersistent human activity can homogenize both structure and function of an $ C; q) p2 r+ X' a% R; B7 F
ecological system, while weakening the diversity-related mechanisms needed to
. M7 O6 S; s3 G# E3 j1 j! ]compensate for sudden disturbance. There are many terrestrial systems today that
& ?: t) X) `3 H2 {: [have become homogenized by persistent human activity that may be similarly ; ^- y6 n" d+ P: _7 w
vulnerable to sudden environmental change that will be only evident after the
8 o) B% D2 l) \( t' A$ M. q% d* e, Ucollapse occurs. On the cover 'grass fire' (Dariush ; Z9 V6 C  B: X  [6 j
M/Shutterstock).& C4 M8 r7 r3 Q6 v0 w
) ~& ]9 V: ^: i0 N2 B. M: E
9 E) f2 A% \, P' h( j

游客，如果你要查看本帖隐藏内容请回复

( C2 C: B3 J! F7 V# B3 X
& p- @, ]# Y' {: r& d