长江三峡地区灌丛草地山羊放牧利用研究
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摘要
本研究于1999年5月—9月和2000年6月—9月在湖北省长阳县贺家坪天然灌丛草
地上进行。试验分为三个处理：对照、轻牧和重牧，并在此基础上选用9只当地羯山羊，
较系统地研究了灌丛草地在不同山羊放牧率下的群落结构、生产力和营养价值动态以及在
不同放牧强度下山羊对灌丛草地植物的喜食性变化。
试验结果表明：（1）试验地区灌木植物的冠幅（D）与当年生枝叶产量和地上生物量
（Y）均呈显著正相关（p＜0.01）：Y=a·D，a为常数，因灌木种的不同而不同。（2）本试
验中，灌丛草地植物粗蛋白含量最高的是灌木植物黄檀，其次是宜昌木蓝和美丽胡枝子，
它们嫩枝叶干物质的粗蛋白含量分别为17%、16%和15.7%，而草本植物芒的粗蛋白含量
最低，仅为4.6%。（3）试验结果表明，轻牧条件下灌木在山羊日粮中的比例均高于重牧：
1999年7月轻牧为62%，重牧为55%，9月轻牧为78%，重牧为51%，2000年6月轻牧
为61.2%，重牧为44.4%，8月轻牧为36.2%，重牧为23.2%；1999年试验中，山羊对
灌木植物的喜食性指数为33%，且极显著高于草本植物（p＜0.01），而禾草和杂类草的喜
食性指数分别仅为9%和4%，2000年的试验中，灌木、禾草和杂类草的喜食性指数分别
为21.3%、13%和11.6%，且三者的喜食性指数间没有显著差异（p＞0.05）。（4）试验发现，
在对照、轻牧和重牧处理下，三峡地区灌丛草地禾草、灌木和杂类草的产量组成依次分别
为：3.7：1.5∶1、5.3∶1.6∶1、1.5∶1.2∶1，故灌丛草地植物的产量主要取决于禾草的季
节消长，其产量动态变化趋势与总产草量的变化基本一致；9月份（9月23日测定）产草
量最高，对照、轻牧和重牧三个处理的总产草量分别为3042.8DM kg/ha、2518.4 DM kg/ha
和1180.3 DM kg/ha，总体来看，随放牧强度的增加，灌丛草地中禾草的月平均地上生物量
依次递减；充足的降雨量为植物在一定程度内补偿生长或超补偿生长提供了保障，从而补
充了被家畜采食掉的生物量。6月份生长季降雨量是8月份的1倍。8月份降雨严重不足，
故8月份轻度和重度放牧下，灌丛草地植物的净初级生长量都低于对照，都表现出欠补偿
生长的特性。6月份轻牧处理下灌丛草地植物的净生长量最高，分别比对照和重牧高出99
DM kg/ha和61 DM kg/ha，这说明6月份灌丛草地在轻度利用下，表现超补偿生长，而在
重牧利用下，逐渐表现出欠补偿生长趋势；从6月的平均放牧利用率来看，山羊对灌丛草
地三类植物的放牧利用程度由大到小依次分别为：禾草、杂类草和灌木，它们的平均放牧
利用率分别为53.4％、40.4％和9.1％；从8月的平均放牧利用率来看，山羊对灌丛草地三
类植物的放牧利用程度由大到小依次分别为：杂类草、禾草和灌木，它们的平均放牧利用
率分别为73％、47.4％和39％。（5）试验结果表明：对照区灌木群落的物种多样性和均匀
度指数随季节的推移变化不大，两者的平均值分别为2.0873和0.8715，轻牧区灌木群落的
物种多样性和均匀度指数总体上呈下降趋势，其下降幅度分别为 10二2％和 16．07％，重牧
区灌木群落的物种多样性和均匀度指数总体上呈上升趋势，其上升幅度均为 5．85％。总的
看来，放牧状态下灌木群落的物种多样性和均匀度指数的相对变化趋势一致：轻牧态下灌
木群落的物种多样性和均匀度指数均为下降趋势，重牧态下灌木群落的物种多样性和均匀
度指数均为上升趋势。放牧状态下草本群落的物种多样性和均匀度指数均为下降趋势，说
明只要存在外界干扰（放牧），就能使草本群落的物种多样性和均匀度指数下降，尤其是
重牧处理能使草本群落的物种多样性指数大幅下降，平均下降幅度为 门．42％。试验结果
表明，放牧尤其是重牧能使美丽胡枝子在灌木群落中的优势地位下降，这与其粗蛋白质含
量较高、适口性较好有关，而较长时间的再生又能恢复或提高其在灌木群落中的优势地位。
1999年的试验结果发现，放牧期间，宜昌木蓝在灌木群落中的重要值下降，说明放牧能影
响其再生，导致宜昌木蓝在灌木群落中的优势性下降。2000年的试验结果说明：轻牧能刺
激宜昌木蓝的再生，但由于其牧后的再生要比其它灌木植物缓慢，故宜昌木蓝的优势性下
降。因此，应该严格控制其放牧强度，才不致于使宜昌木蓝从灌木群落中衰减甚至消失。
（6）试验结果表明，不同放牧强度对山羊的日增重有明显的影响，轻牧区日增重高于重
牧区。不同放牧时间对山羊的日增重影响极显著，5月份放牧山羊的平均日增重极显著高
于（p＜0．of）7月和 9月放牧的山羊。5月、7月和 9月放牧山羊的平均日增重轻牧和重牧
分别为 190和 120g、38．46和 15．389、22．2和 11．ig。灌木中可利用营养物质的含量对山羊
的体重会产生明显的影响，当灌木中可利用的粗蛋白含量较高，而粗纤维含量较低时，有
利于提高山羊的生产性能。在本试验中，禾草、杂类草、灌木以及灌丛草地植物群落的总
体保护指标分别为 786．8、360．3、394．6和 1541．6DM kg／ha。如以生物量作为灌丛草地保护
指标的衡量标准，优势灌木植物白烁、麻株、美丽胡枝子和盐肤木的
A study was conducted on a naturely shrubland of Hejiaping on the
county of Changyang in
Hubei Province from May to September in 1999 and from June to
September in 2000.The study
with 9 local wethers was designed as three treatments including
the control, the light- and heavy-
grazing. The changes of community structure, yield, nutrition of
shrubland and acceptability index
of shrubland plant under the different grazing intensities were
systematically studied.
The results were showed as follows: (1) The extremely significant
(p<0.01)positive
correlation between the fresh weight (Y) of new branches and
leaves and up-ground and crown
width (D) could be expressed by a function as Y=a D in the study.
(2) The content of crude
protein of Dacbergia hupeana Hance. was the highest, those of
Jndigofrra ic/zangensis Craib and
LespedezaformosaLes were in the second places, and their contents
of crude protein in the dry
matter were 17%, 16% and 15.7% respectively. The content of crude
protein of Miscanthus
sinensis was the lowest (4.6%). (3) The dietary composition of
shrub was higher under the light-
grazing treatment than under the heavy-grazing treatment (1999
and 2000). The dietary
composition of shrub (1999) under the light- and heavy-grazing
treatments were 62% and 55%
respectively in July, and were 78% and 51% respectively in
September. The dietary composition
of shrub (2000) under the light- and heavy-grazing treatments
were 6 1.2% and 44.4% respectively
in June, and were 36.2% and 23.2% respectively in August. The
acceptability index of shrubby
plants in 1999 was 33% and extremely significant (p than that of herbage plants, and
those of grasses and forb were 9% and 4% respectively. There were
no significant differences
(p>O.O5) in the acceptability index of shrubs, grasses and forb
in 2000 (21.3%, 13% and 11.6%
respectively). (4) The yield composition and seasonal change on
shrubland in the Three Gorges
Region of Yangtz river mainly depended on the seasonal growth and
decline of grasses, and the
changing trends of production of grasses and total yield of
shrubland were consistent. The yields
of the control, the light- and heavy-grazing treatments in
September were the highest and were
3042.8, 2518.4 and 1180.3DM kg/ha respectively. A lot of rainfall
could play a role in a certain
degree in the compensatory growth of plants that were consumed by
animals. The net primary
growth of plant on shrubland was lower under the light- and
heavy-grazing treatment than under
the control treatment in August because of the severe lack of
rainfall. The net growth of plant was
over-compensatory under the light-grazing treatment and
low-compensatory under the heavy-
grazing treatment. The average utilization efficiencies of
grasses, forb and shrubs were 53.4%,
40.4% and 9.1% respectively in June and were 47.4%, 73% and 39%
respectively in August. (5)
The species diversity and even index of shrubby community almost
kept constant under the
control treatment and their average values were 2.0876 and 0.8715
respectively. The species
diversity and even index of shrubby community declined under the
light-grazing treatment and
increased under the heavy-grazing treatment. The species
diversity and even index of herbage
community declined under the light- and heavy-grazing
treatments.The superiority of Lespedeza
formosa/es in shrubby community declined under the grazing
treatment especially the heavy-
grazing treatment because of its relatively high content of crude
protein and good preference, and
sequential regrowth would improve its superiority in shrubby
community. The regrowth of
Indigofera ic/langensis Craib was stimulated under the
light-grazing treatment and was affected
under the heavy-grazing treatment, so the stocking rate should be
control lest Indigofera
ichangensis Craib decline. (6) The daily gains of grazi
地上进行。试验分为三个处理：对照、轻牧和重牧，并在此基础上选用9只当地羯山羊，
较系统地研究了灌丛草地在不同山羊放牧率下的群落结构、生产力和营养价值动态以及在
不同放牧强度下山羊对灌丛草地植物的喜食性变化。
试验结果表明：（1）试验地区灌木植物的冠幅（D）与当年生枝叶产量和地上生物量
（Y）均呈显著正相关（p＜0.01）：Y=a·D，a为常数，因灌木种的不同而不同。（2）本试
验中，灌丛草地植物粗蛋白含量最高的是灌木植物黄檀，其次是宜昌木蓝和美丽胡枝子，
它们嫩枝叶干物质的粗蛋白含量分别为17%、16%和15.7%，而草本植物芒的粗蛋白含量
最低，仅为4.6%。（3）试验结果表明，轻牧条件下灌木在山羊日粮中的比例均高于重牧：
1999年7月轻牧为62%，重牧为55%，9月轻牧为78%，重牧为51%，2000年6月轻牧
为61.2%，重牧为44.4%，8月轻牧为36.2%，重牧为23.2%；1999年试验中，山羊对
灌木植物的喜食性指数为33%，且极显著高于草本植物（p＜0.01），而禾草和杂类草的喜
食性指数分别仅为9%和4%，2000年的试验中，灌木、禾草和杂类草的喜食性指数分别
为21.3%、13%和11.6%，且三者的喜食性指数间没有显著差异（p＞0.05）。（4）试验发现，
在对照、轻牧和重牧处理下，三峡地区灌丛草地禾草、灌木和杂类草的产量组成依次分别
为：3.7：1.5∶1、5.3∶1.6∶1、1.5∶1.2∶1，故灌丛草地植物的产量主要取决于禾草的季
节消长，其产量动态变化趋势与总产草量的变化基本一致；9月份（9月23日测定）产草
量最高，对照、轻牧和重牧三个处理的总产草量分别为3042.8DM kg/ha、2518.4 DM kg/ha
和1180.3 DM kg/ha，总体来看，随放牧强度的增加，灌丛草地中禾草的月平均地上生物量
依次递减；充足的降雨量为植物在一定程度内补偿生长或超补偿生长提供了保障，从而补
充了被家畜采食掉的生物量。6月份生长季降雨量是8月份的1倍。8月份降雨严重不足，
故8月份轻度和重度放牧下，灌丛草地植物的净初级生长量都低于对照，都表现出欠补偿
生长的特性。6月份轻牧处理下灌丛草地植物的净生长量最高，分别比对照和重牧高出99
DM kg/ha和61 DM kg/ha，这说明6月份灌丛草地在轻度利用下，表现超补偿生长，而在
重牧利用下，逐渐表现出欠补偿生长趋势；从6月的平均放牧利用率来看，山羊对灌丛草
地三类植物的放牧利用程度由大到小依次分别为：禾草、杂类草和灌木，它们的平均放牧
利用率分别为53.4％、40.4％和9.1％；从8月的平均放牧利用率来看，山羊对灌丛草地三
类植物的放牧利用程度由大到小依次分别为：杂类草、禾草和灌木，它们的平均放牧利用
率分别为73％、47.4％和39％。（5）试验结果表明：对照区灌木群落的物种多样性和均匀
度指数随季节的推移变化不大，两者的平均值分别为2.0873和0.8715，轻牧区灌木群落的
物种多样性和均匀度指数总体上呈下降趋势，其下降幅度分别为 10二2％和 16．07％，重牧
区灌木群落的物种多样性和均匀度指数总体上呈上升趋势，其上升幅度均为 5．85％。总的
看来，放牧状态下灌木群落的物种多样性和均匀度指数的相对变化趋势一致：轻牧态下灌
木群落的物种多样性和均匀度指数均为下降趋势，重牧态下灌木群落的物种多样性和均匀
度指数均为上升趋势。放牧状态下草本群落的物种多样性和均匀度指数均为下降趋势，说
明只要存在外界干扰（放牧），就能使草本群落的物种多样性和均匀度指数下降，尤其是
重牧处理能使草本群落的物种多样性指数大幅下降，平均下降幅度为 门．42％。试验结果
表明，放牧尤其是重牧能使美丽胡枝子在灌木群落中的优势地位下降，这与其粗蛋白质含
量较高、适口性较好有关，而较长时间的再生又能恢复或提高其在灌木群落中的优势地位。
1999年的试验结果发现，放牧期间，宜昌木蓝在灌木群落中的重要值下降，说明放牧能影
响其再生，导致宜昌木蓝在灌木群落中的优势性下降。2000年的试验结果说明：轻牧能刺
激宜昌木蓝的再生，但由于其牧后的再生要比其它灌木植物缓慢，故宜昌木蓝的优势性下
降。因此，应该严格控制其放牧强度，才不致于使宜昌木蓝从灌木群落中衰减甚至消失。
（6）试验结果表明，不同放牧强度对山羊的日增重有明显的影响，轻牧区日增重高于重
牧区。不同放牧时间对山羊的日增重影响极显著，5月份放牧山羊的平均日增重极显著高
于（p＜0．of）7月和 9月放牧的山羊。5月、7月和 9月放牧山羊的平均日增重轻牧和重牧
分别为 190和 120g、38．46和 15．389、22．2和 11．ig。灌木中可利用营养物质的含量对山羊
的体重会产生明显的影响，当灌木中可利用的粗蛋白含量较高，而粗纤维含量较低时，有
利于提高山羊的生产性能。在本试验中，禾草、杂类草、灌木以及灌丛草地植物群落的总
体保护指标分别为 786．8、360．3、394．6和 1541．6DM kg／ha。如以生物量作为灌丛草地保护
指标的衡量标准，优势灌木植物白烁、麻株、美丽胡枝子和盐肤木的
A study was conducted on a naturely shrubland of Hejiaping on the
county of Changyang in
Hubei Province from May to September in 1999 and from June to
September in 2000.The study
with 9 local wethers was designed as three treatments including
the control, the light- and heavy-
grazing. The changes of community structure, yield, nutrition of
shrubland and acceptability index
of shrubland plant under the different grazing intensities were
systematically studied.
The results were showed as follows: (1) The extremely significant
(p<0.01)positive
correlation between the fresh weight (Y) of new branches and
leaves and up-ground and crown
width (D) could be expressed by a function as Y=a D in the study.
(2) The content of crude
protein of Dacbergia hupeana Hance. was the highest, those of
Jndigofrra ic/zangensis Craib and
LespedezaformosaLes were in the second places, and their contents
of crude protein in the dry
matter were 17%, 16% and 15.7% respectively. The content of crude
protein of Miscanthus
sinensis was the lowest (4.6%). (3) The dietary composition of
shrub was higher under the light-
grazing treatment than under the heavy-grazing treatment (1999
and 2000). The dietary
composition of shrub (1999) under the light- and heavy-grazing
treatments were 62% and 55%
respectively in July, and were 78% and 51% respectively in
September. The dietary composition
of shrub (2000) under the light- and heavy-grazing treatments
were 6 1.2% and 44.4% respectively
in June, and were 36.2% and 23.2% respectively in August. The
acceptability index of shrubby
plants in 1999 was 33% and extremely significant (p
those of grasses and forb were 9% and 4% respectively. There were
no significant differences
(p>O.O5) in the acceptability index of shrubs, grasses and forb
in 2000 (21.3%, 13% and 11.6%
respectively). (4) The yield composition and seasonal change on
shrubland in the Three Gorges
Region of Yangtz river mainly depended on the seasonal growth and
decline of grasses, and the
changing trends of production of grasses and total yield of
shrubland were consistent. The yields
of the control, the light- and heavy-grazing treatments in
September were the highest and were
3042.8, 2518.4 and 1180.3DM kg/ha respectively. A lot of rainfall
could play a role in a certain
degree in the compensatory growth of plants that were consumed by
animals. The net primary
growth of plant on shrubland was lower under the light- and
heavy-grazing treatment than under
the control treatment in August because of the severe lack of
rainfall. The net growth of plant was
over-compensatory under the light-grazing treatment and
low-compensatory under the heavy-
grazing treatment. The average utilization efficiencies of
grasses, forb and shrubs were 53.4%,
40.4% and 9.1% respectively in June and were 47.4%, 73% and 39%
respectively in August. (5)
The species diversity and even index of shrubby community almost
kept constant under the
control treatment and their average values were 2.0876 and 0.8715
respectively. The species
diversity and even index of shrubby community declined under the
light-grazing treatment and
increased under the heavy-grazing treatment. The species
diversity and even index of herbage
community declined under the light- and heavy-grazing
treatments.The superiority of Lespedeza
formosa/es in shrubby community declined under the grazing
treatment especially the heavy-
grazing treatment because of its relatively high content of crude
protein and good preference, and
sequential regrowth would improve its superiority in shrubby
community. The regrowth of
Indigofera ic/langensis Craib was stimulated under the
light-grazing treatment and was affected
under the heavy-grazing treatment, so the stocking rate should be
control lest Indigofera
ichangensis Craib decline. (6) The daily gains of grazi
引文
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