不同降水条件下内蒙古荒漠草原主要植物物候对长期增温和氮添加的响应

doi:10.17521/cjpe.2021.0277

植物生态学报 ›› 2022, Vol. 46 ›› Issue (3): 290-299.DOI: 10.17521/cjpe.2021.0277

所属专题：全球变化与生态系统

不同降水条件下内蒙古荒漠草原主要植物物候对长期增温和氮添加的响应

田磊, 朱毅, 李欣, 韩国栋, 任海燕^*()

内蒙古农业大学草原与资源环境学院, 草地资源教育部重点实验室, 内蒙古自治区草地管理与利用重点实验室, 呼和浩特 010011

收稿日期:2021-07-26 接受日期:2021-09-26 出版日期:2022-03-20 发布日期:2021-12-16
通讯作者: 任海燕
作者简介:* (renhy@imau.edu.cn)
基金资助:
内蒙古自治区应用技术研究与开发资金项目(2021GG0088);内蒙古重大专项和成果转化项目(ZDZX2018020);内蒙古重大专项和成果转化项目(2019CG069)

Responses of plant phenology to warming and nitrogen addition under different precipitation conditions in a desert steppe of Nei Mongol, China

TIAN Lei, ZHU Yi, LI Xin, HAN Guo-Dong, REN Hai-Yan^*()

Key Laboratory of Grassland Resources of the Ministry of Education, Inner Mongolia Key Laboratory of Grassland Management and Utilization, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010011, China

Received:2021-07-26 Accepted:2021-09-26 Online:2022-03-20 Published:2021-12-16
Contact: REN Hai-Yan
Supported by:
Applied Technology Research and Development Fund of Inner Mongolia(2021GG0088);Inner Mongolia Major Projects and Achievements Transformation Projects(ZDZX2018020);Inner Mongolia Major Projects and Achievements Transformation Projects(2019CG069)

摘要/Abstract

摘要：

植物物候是生态系统对气候变化响应的重要指示器, 是植物生产力与植被动态模拟的重要参数。但是植物物候对全球变化的响应是否存在年际间变异、年内变异、物种间变异或生境间变异, 以及如何改变, 目前仍然不明确。该研究基于内蒙古荒漠草原长期增温和氮添加实验平台, 选择优势植物短花针茅(Stipa breviflora)、冷蒿(Artemisia frigida)和木地肤(Kochia prostrata)为研究对象, 使用物候打分观测方法和Richards生长曲线拟合方法, 研究了实验处理第11、12和13年(2016-2018年)期间增温和氮添加对植物物候的影响。研究结果表明: (1)短花针茅开花时间集中在第129-145天, 冷蒿开花时间集中在第230-248天, 木地肤开花时间集中在第194-222天。增温、氮添加和增温+氮添加均使短花针茅和木地肤开花时间趋于提前, 冷蒿开花时间趋于推迟。(2)短花针茅结果时间集中在第134-148天, 冷蒿结果时间集中在第241-260天, 木地肤结果时间集中在第207-231天。增温、氮添加和增温+氮添加处理均使短花针茅和木地肤结果时间趋于提前, 冷蒿结果时间趋于推迟。(3)短花针茅生殖生长持续12-25天, 冷蒿生殖生长持续48-55天, 木地肤生殖生长持续45-77天。增温、增温+氮添加缩短了短花针茅而延长了冷蒿和木地肤的生殖生长时间。

关键词: 荒漠草原, 植物物候, 增温, 氮沉降, 降水

Abstract:

Aims Plant phenology is an important indicator of ecosystem response to climate change, and it is also a central parameter for modelling plant productivity and vegetation dynamics. However, it remains unclear whether inner-annual, intra-annual, inter-species or inter-habitat variabilities exist in the response of plant phenology to environmental changes.
Methods Here we investigated the effects of long-term (>10 years) warming and nitrogen (N) addition on plant phenology in a temperate desert steppe. We used the phenological scoring observation method and Richards growth curve fitting method to monitor phenological shifts of three dominant species, Stipa breviflora, Artemisia frigida and Kochia prostrata, in the 11th, 12th and 13th treatment year.
Important findings We found that the flowering time ranged from the 129th to the 145th days of a year for S. breviflora, from the 230th to the 248th days for A. frigida, and from the 194th to the 222th days for K. prostrata. Warming and N addition tended to advance the flowering time of S. breviflora and K. prostrata, but tended to delay the flowering time of A. frigida. The fruiting time ranged from the 134th to the 148th days for S. breviflora, from the 241th to the 260th days for A. frigida, and from the 207th to the 231th days for K. prostrata. Warming and N addition tended to advance the fruiting time of S. breviflora and K. prostrata, but tended to delay that of A. frigida. The reproductive growth period lasted for 12 to 25 days for S. breviflora, 48 to 55 days for A. frigida, and 45 to 77 days for K. prostrata. Warming and N addition shortened the reproductive growth period for S. breviflora, but prolonged that period for A. frigida and K. prostrata.

Key words: desert steppe, plant phenology, warming, nitrogen deposition, precipitation

田磊, 朱毅, 李欣, 韩国栋, 任海燕. 不同降水条件下内蒙古荒漠草原主要植物物候对长期增温和氮添加的响应. 植物生态学报, 2022, 46(3): 290-299. DOI: 10.17521/cjpe.2021.0277

TIAN Lei, ZHU Yi, LI Xin, HAN Guo-Dong, REN Hai-Yan. Responses of plant phenology to warming and nitrogen addition under different precipitation conditions in a desert steppe of Nei Mongol, China. Chinese Journal of Plant Ecology, 2022, 46(3): 290-299. DOI: 10.17521/cjpe.2021.0277

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链接本文: https://www.plant-ecology.com/CN/10.17521/cjpe.2021.0277

https://www.plant-ecology.com/CN/Y2022/V46/I3/290

图/表 10

图1 内蒙古短花针茅荒漠草原研究区2016-2018年降水量。A, 2016-2018年月降水量。B, 2016-2018年年降水量。

Fig. 1 Precipitation in the study area in the Stipa breviflora desert grassland of Nei Mongol from 2016 to 2018. A, Monthly precipitation of 2016 to 2018. B, Annual precipitation of 2016 to 2018.

表1 内蒙古短花针茅荒漠草原禾草类和非禾草类物候打分法赋值情况

Table 1 Specific phenological scoring of grass and forb in the Stipa breviflora desert grassland of Nei Mongol

分值 Score	禾草类 Grass	非禾草类 Forb
0	小穗尚在苞叶内 Spikelets in boot	尚未开花 Not blooming
1	小穗伸出苞叶内 Spikelets out of boot	花芽可见 Flower bud present
2	花粉囊、花柱已伸出 Exserted anthers & styles	开花 Blooming
3	种子正在发育形成 Seed developing	花开始衰老 Decaying
3.5	种子开始脱落、散布 Seed dropping	-
4	种子全部脱落 All seed dropped	-
4.5	-	果实可见 Fruit present
5.5	-	果实开始开裂 Fruit dehiscing
6	-	所有果实开裂 All fruits dehisced

图2 内蒙古短花针茅荒漠草原不同物种Richards生长方程拟合图。B, 开花时间; F, 结果时间; R, 生殖生长时间。

Fig. 2 Fitting diagram of Richards growth equation for different species in the Stipa breviflora desert grassland of Nei Mongol. B, blooming time; F, fruiting time; R, reproductive growth time.

图3 不同降水条件下增温和氮添加对内蒙古短花针茅荒漠草原植物开花时间(平均值±标准误)的影响。CK, 对照; N, 氮添加; W, 增温; WN, 增温+氮添加。不同小写字母表示不同处理间的差异达到显著水平(p < 0.05)。

Fig. 3 Effects of warming and nitrogen addition on plants flowering time (mean ± SE) under different precipitation conditions in the Stipa breviflora desert grassland of Nei Mongol. CK, control; N, nitrogen addition; W, warming; WN, warming + nitrogen addition. Different lowercase letters indicated significant differences among different treatments (p < 0.05).

表2 增温(W)、氮添加(N)和不同降水量(P)对内蒙古短花针茅荒漠草原物种开花时间影响的混合效应模型分析

Table 2 Mixed effects modeling analysis for the effects of warming (W), nitrogen addition (N) and different precipitation (P) on plant flowering time in the Stipa breviflora desert grassland of Nei Mongol

处理 Treatment	短花针茅 Stipa breviflora			冷蒿 Artemisia frigida			木地肤 Kochia prostrata
处理 Treatment	Num df	Den df	F	Num df	Den df	F	Num df	Den df	F
W	1	15	554.20^***	1	12	15.40^**	1	15	274.30^***
N	1	15	23.70^***	1	12	0.10	1	15	4.00
P	1	44	2176.20^***	1	31	1540.70^***	1	43	2750.40^***
W × N	1	15	1.60	1	12	46.30^***	1	15	5.10^*
W × P	1	44	27.90^***	1	31	10.00^**	1	43	12.80^***
N × P	1	44	3.80	1	31	12.70^**	1	43	16.00^***
W × N × P	1	44	5.90^*	1	31	6.50^*	1	43	2.30

图4 不同降水条件下增温和氮添加对内蒙古短花针茅荒漠草原植物结果时间(平均值±标准误)的影响。CK, 对照; N, 氮添加; W, 增温; WN, 增温+氮添加。不同小写字母表示不同处理间的差异达到显著水平(p < 0.05)。

Fig. 4 Effects of warming and nitrogen addition on plants fruiting time (mean ± SE) under different precipitation conditions in the Stipa breviflora desert grassland of Nei Mongol. CK, control; N, nitrogen addition; W, warming; WN, warming + nitrogen addition. Different lowercase letters indicated significant differences among different treatments (p < 0.05).

表3 增温(W)、氮添加(N)和不同降水量(P)对内蒙古短花针茅荒漠草原植物结果时间影响的混合效应模型分析

Table 3 Mixed effects modeling analysis for the effects of warming (W), nitrogen addition (N) and different precipitation (P) on plant fruiting time in the Stipa breviflora desert grassland of Nei Mongol

处理 Treatment	短花针茅 Stipa breviflora			冷蒿 Artemisia frigida			木地肤 Kochia prostrata
处理 Treatment	Num df	Den df	F	Num df	Den df	F	Num df	Den df	F
W	1	15	1710.10^***	1	12	7.70^*	1	15	82.80^***
N	1	15	41.00^***	1	12	0.70	1	15	0.50
P	1	44	4947.80^***	1	31	1 448.70^***	1	44	922.00^***
W × N	1	15	2.10	1	12	6.00^*	1	15	0.00
W × P	1	44	32.90^***	1	31	8.20^**	1	44	18.90^***
N × P	1	44	6.60^*	1	31	12.10^**	1	44	23.90^***
W × N × P	1	44	19.00^***	1	31	0.00	1	44	10.60^**

图5 不同降水条件下增温和氮添加对内蒙古短花针茅荒漠草原植物生殖生长时间(平均值±标准误)的影响。CK, 对照; N, 氮添加; W, 增温; WN, 增温+氮添加。不同小写字母表示不同处理间的差异达到显著水平(p < 0.05)。

Fig. 5 Effects of warming and nitrogen addition on plants reproductive growth time (mean ± SE) under different precipitation conditions in the Stipa breviflora desert grassland of Nei Mongol. CK, control; N, nitrogen addition; W, warming; WN, warming + nitrogen addition. Different lowercase letters indicated significant differences among different treatments (p < 0.05).

表4 增温(W)、氮添加(N)和不同降水量(P)对内蒙古短花针茅荒漠草原植物生殖生长时间影响的混合效应模型分析

Table 4 Mixed effects modeling analysis for the effects of warming (W), nitrogen addition (N) and different precipitation (P) on plant reproductive growth time in the Stipa breviflora desert grassland of Nei Mongol

处理 Treatment	短花针茅 Stipa breviflora			冷蒿 Artemisia frigida			木地肤 Kochia prostrata
处理 Treatment	Num df	Den df	F	Num df	Den df	F	Num df	Den df	F
W	1	15	4.09	1	12	1.28	1	15	108.99^***
N	1	15	1.74	1	12	0.82	1	15	7.49^*
P	1	44	49.44^***	1	31	19.83^***	1	44	69.33^***
W × N	1	15	0.50	1	12	1.19	1	15	1.00
W × P	1	44	0.01	1	31	4.20^*	1	44	5.80^*
N × P	1	44	0.20	1	31	0.16	1	44	0.08
W × N × P	1	44	0.28	1	31	0.38	1	44	2.71

图6 不同降水条件对内蒙古短花针茅荒漠草原短花针茅、冷蒿和木地肤开花、结果和生殖生长时间的影响。CK, 对照; N, 氮添加; W, 增温; WN, 增温+氮添加。

Fig. 6 Effects of different precipitation conditions on flowering, fruiting and reproductive growth time of Stipa breviflora, Artemisia frigida and Kochia prostrata in the Stipa breviflora desert grassland of Nei Mongol. CK, control; N, nitrogen addition; W, warming; WN, warming + nitrogen addition.

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不同降水条件下内蒙古荒漠草原主要植物物候对长期增温和氮添加的响应

Responses of plant phenology to warming and nitrogen addition under different precipitation conditions in a desert steppe of Nei Mongol, China

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