Paper · 2021 · Acta Ecologica Sinica

Changes in root biomass of grassland along the environmental gradient in the Loess Plateau

孙天雨,王雪,李丹洋,刘欣蕊,王瑞丽,张硕新 SUN Tianyu

12
claims
21
verbatim quotes
1
citations
2
research areas
—
Not open access

Abstract

草地是陆地生态系统的重要组成部分,根系生物量是研究草地生态系统的重要参数之一,研究草地根系生物量沿环境梯度的变化规律对当地的植被建设和恢复具有重要意义。以黄土高原3种不同草地类型(森林草原、典型草原和荒漠草原)为研究对象,沿环境梯度从东到西选择10个样地,每个样地内设置8个1 m×1 m样方进行根系生物量的调查,旨在分析不同草地类型根系生物量的垂直分布规律,并探讨了根系生物量沿环境梯度的变化规律及其影响因素。结果表明:(1)黄土高原3种草地类型根系生物量有显著差别(P<0.05),其中森林草原的根系生物量最大,典型草原最小;(2)3种不同草地类型根系生物量垂直分布均呈"T"型,土壤表层(0-10 cm)占55%以上的根系生物量,且荒漠草原根系有更多比例的生物量分布在土壤表层;(3)黄土高原草地根系生物量沿经度从东到西呈现先减少后缓慢增加的趋势,但浅层生物量与深层生物量比例(浅深比)没有表现出明显的经度格局;(4)总根系生物量的变化主要受年均温(MAT)影响(P<0.01),随MAT增大而增大;深层生物量同时受气候和土壤养分含量的影响(P<0.01);浅深比则与样点平均土壤全磷含量、深层土壤全磷含量有显著负相关性(P<0.05);(5)气候和土壤因素能解释根系生物量5.12%-39.36%的变异,独立作用中,气候因子对根生物量的解释度最大,可达到2.77%-9.12%的解释度。;Grassland is an important part of terrestrial ecosystem, plant root system plays a critical role in the growth and development of the whole plant, which has the basic functions of storing nutrients, transporting water and supporting plant body. And root biomass is one of the important bases and parameters for studying grassland ecosystem. Thus, studying how root biomass of the grassland changes along environmental gradient is of great significance to local vegetation construction and restoration. Here, we selected ten sites from east to west in the Loess Plateau, which covered the main grassland types, including forest grassland, typical grassland and desert grassland. At each site, the roots of grassland plant were sampled to 0 cm to 50 cm soil depth at eight experimental plots (1m×1m) by using roots cores. We aimed to reveal the vertical distribution of root biomass of three different grassland types in the Loess Plateau, and explore the pattern of root biomass along the environmental gradients and their influencing factors. Our results showed that: (1) the root biomass of three different grassland types in the Loess Plateau was significantly different (P<0.05), with the root biomass of forest grassland being the largest and that of typical grassland being the smallest. (2) All of the root biomass vertical distributions of the three different grassland types in the Loess Plateau were T type, and the surface soil (0-10 cm) accounted for more than 55% of total root biomass. Moreover, more proportion of the root biomass of the desert grassland was distributed on the surface soil. (3) As the longitude increased, the grassland root biomass of the Loess Plateau decreased first, and then increased. However, the ratio of the root biomass of shallow soil layer to the root biomass of deep soil layer (i.e., shallow-deep ratio) did not show an obvious longitudinal pattern. (4) The change in total root biomass was affected positively by the mean annual temperature (MAT)(P<0.01). But the root biomass of deep soil layer was affected by both climate and soil nutrient content(P<0.01), and the shallow-deep ratio was influenced negatively by the total soil phosphorus of average soli layer and deep soil layer (P<0.05). (5) Climate and soil factors could explain 5.12-39.36% of the variation in root biomass, among the independent effects, climate factors had the largest explanatory degree to root biomass, which could reach 2.77%-9.12%.

Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗

The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.

Claims 12

Observationobservedoriginal resultsignificant (as stated)measured

Claim · model-written summary

Root biomass differs significantly among three grassland types, greatest in forest grassland and least in typical grassland.

Taxon
grasslande0
Outcome
root biomasse0
Direction
largeste0
Comparator
typical grasslande0
Setting
Loess Plateaue0

Verbatim

e0

“the root biomass of three different grassland types in the Loess Plateau was significantly different (P<0.05), with the root biomass of forest grassland being the largest and that of typical grassland being the smallest.”

✓ located verbatim in the source · abstract, characters 1670–1890 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

All three grassland types show T type vertical root biomass distributions.

Taxon
grasslande0
Outcome
root biomass vertical distributionse0
Setting
Loess Plateaue0

Verbatim

e0

“All of the root biomass vertical distributions of the three different grassland types in the Loess Plateau were T type”

✓ located verbatim in the source · abstract, characters 1895–2013 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

The surface 0-10 cm accounts for more than 55% of total root biomass.

Taxon
grasslandt0
Organ / stage
surface soil (0-10 cm)e0
Outcome
total root biomasse0
Value
more than 55%e0

Verbatim

t0

“grassland”

✓ located verbatim in the source · title, characters 27–36 · show in text ↑
e0

“the surface soil (0-10 cm) accounted for more than 55% of total root biomass”

✓ located verbatim in the source · abstract, characters 2019–2095 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

Desert grassland has a greater share of root biomass in surface soil.

Taxon
desert grasslande0
Outcome
proportion of the root biomasse0
Direction
moree0

Verbatim

e0

“more proportion of the root biomass of the desert grassland was distributed on the surface soil”

✓ located verbatim in the source · abstract, characters 2107–2202 · show in text ↑
Associationobservedoriginal resultmeasured

Claim · model-written summary

Grassland root biomass first decreases and then increases as longitude increases.

Taxon
grasslande0
Outcome
root biomasse0
Direction
decreased first, and then increasede0
Setting
Loess Plateaue0

Verbatim

e0

“As the longitude increased, the grassland root biomass of the Loess Plateau decreased first, and then increased.”

✓ located verbatim in the source · abstract, characters 2208–2320 · show in text ↑
Associationobservedoriginal resultno effectmeasured

Claim · model-written summary

The shallow to deep root biomass ratio shows no obvious longitudinal pattern.

Taxon
grasslandt0
Outcome
shallow-deep ratioe0
Direction
did not show an obvious longitudinal patterne0

Not reportedSetting

Verbatim

t0

“grassland”

✓ located verbatim in the source · title, characters 27–36 · show in text ↑
e0

“the ratio of the root biomass of shallow soil layer to the root biomass of deep soil layer (i.e., shallow-deep ratio) did not show an obvious longitudinal pattern”

✓ located verbatim in the source · abstract, characters 2330–2492 · show in text ↑
Associationobservedoriginal resultsignificant (as stated)measured

Claim · model-written summary

Total root biomass is positively related to mean annual temperature.

Taxon
grasslandt0
Outcome
total root biomasse0
Direction
positivelye0
Qualifier
mean annual temperature (MAT)e0
Setting
grasslandt0

Verbatim

t0

“grassland”

✓ located verbatim in the source · title, characters 27–36 · show in text ↑
e0

“The change in total root biomass was affected positively by the mean annual temperature (MAT)(P<0.01).”

✓ located verbatim in the source · abstract, characters 2498–2600 · show in text ↑
Associationobservedoriginal resultsignificant (as stated)measured

Claim · model-written summary

Deep soil root biomass is associated with climate and soil nutrient content.

Taxon
grasslandt0
Outcome
root biomass of deep soil layere0
Qualifier
climate and soil nutrient contente0
Setting
grasslandt0

Not reportedDirection

Verbatim

t0

“grassland”

✓ located verbatim in the source · title, characters 27–36 · show in text ↑
e0

“the root biomass of deep soil layer was affected by both climate and soil nutrient content(P<0.01)”

✓ located verbatim in the source · abstract, characters 2605–2703 · show in text ↑
Associationobservedoriginal resultsignificant (as stated)measured

Claim · model-written summary

The shallow to deep root biomass ratio is negatively related to average soil layer total phosphorus.

Taxon
grasslandt0
Organ / stage
average soli layere0
Outcome
shallow-deep ratioe0
Direction
negativelye0
Qualifier
total soil phosphorus of average soli layere0

Verbatim

t0

“grassland”

✓ located verbatim in the source · title, characters 27–36 · show in text ↑
e0

“the shallow-deep ratio was influenced negatively by the total soil phosphorus of average soli layer and deep soil layer (P<0.05)”

✓ located verbatim in the source · abstract, characters 2709–2837 · show in text ↑
Associationobservedoriginal resultsignificant (as stated)measured

Claim · model-written summary

The shallow to deep root biomass ratio is negatively related to deep soil layer total phosphorus.

Taxon
grasslandt0
Organ / stage
deep soil layere0
Outcome
shallow-deep ratioe0
Direction
negativelye0
Qualifier
deep soil layere0

Verbatim

t0

“grassland”

✓ located verbatim in the source · title, characters 27–36 · show in text ↑
e0

“the shallow-deep ratio was influenced negatively by the total soil phosphorus of average soli layer and deep soil layer (P<0.05)”

✓ located verbatim in the source · abstract, characters 2709–2837 · show in text ↑
Associationobservedoriginal resultmeasured

Claim · model-written summary

Climate and soil factors explain 5.12-39.36% of variation in root biomass.

Taxon
grasslandt0
Outcome
variation in root biomasse0
Value
5.12-39.36%e0
Qualifier
Climate and soil factorse0
Setting
Loess Plateaue1

Not reportedDirection

Verbatim

t0

“grassland”

✓ located verbatim in the source · title, characters 27–36 · show in text ↑
e0

“Climate and soil factors could explain 5.12-39.36% of the variation in root biomass”

✓ located verbatim in the source · abstract, characters 2843–2926 · show in text ↑
e1

“the root biomass of three different grassland types in the Loess Plateau was significantly different (P<0.05), with the root biomass of forest grassland being the largest and that of typical grassland being the smallest.”

✓ located verbatim in the source · abstract, characters 1670–1890 · show in text ↑
Associationobservedoriginal resultmeasured

Claim · model-written summary

Climate has the largest independent explanatory contribution to root biomass, reaching 2.77%-9.12%.

Taxon
grasslandt0
Outcome
explanatory degree to root biomasse0
Value
2.77%-9.12%e0
Qualifier
climate factorse0

Not reportedSettingDirection

Verbatim

t0

“grassland”

✓ located verbatim in the source · title, characters 27–36 · show in text ↑
e0

“among the independent effects, climate factors had the largest explanatory degree to root biomass, which could reach 2.77%-9.12%.”

✓ located verbatim in the source · abstract, characters 2928–3057 · show in text ↑