The conservation patterns of grassland ecosystem in response to the forage-livestock balance in North China

doi:10.1007/s11442-021-1856-6

Abstract

Abstract:

Being a key ecological security barrier and production base for grassland animal husbandry in China, the balance between grassland forage supply and livestock-carrying pressure in North China directly affects grassland degradation and restoration, thereby impacting grassland ecosystem services. This paper analyzes the spatiotemporal variation in grassland vegetation coverage, forage supply, and the balance between grassland forage supply and livestock-carrying pressure from 2000 to 2015 in North China. We then discuss the spatial pattern of grassland ecological conservation under the impacts of grassland degradation and restoration, and livestock-carrying pressure. Over the last 16 years, the total grassland area in North China decreased by about 16,000 km ², with vegetation coverage degraded by 6.7% of the grasslands but significantly restored by another 5.4% of grasslands. The provisioning of forage by natural grassland mainly increased over time, with an annual growth rate of approximately 0.3 kg/ha, but livestock-carrying pressure also increased continuously. The livestock-carrying pressure index without any supplementary feeding reached as high as 3.8. Apart from the potential livestock-carrying capacity in northeastern Inner Mongolia and the central Tibetan Plateau, most regions in North China are currently overloaded. Considering the actual supplementary feeding during the cold season, the livestock-carrying pressure index is about 3.1, with the livestock-carrying pressure mitigated in central and eastern Inner Mongolia. Assuming full supplementary feeding in the cold season, livestock-carrying pressure index will fall to 1.9, with the livestock-carrying pressure alleviated significantly in Inner Mongolia and on the Tibetan Plateau. Finally, we propose different conservation and development strategies to balance grassland ecological conservation and animal husbandry production in different regions of protected areas, pastoral areas, farming-pastoral ecotone, and farming areas, according to the grassland ecological protection patterns.

Key words: grassland degradation and restoration, forage supply, livestock-carrying pressure, grassland ecosystem conservation, North China

HUANG Lin, NING Jia, ZHU Ping, ZHENG Yuhan, ZHAI Jun. The conservation patterns of grassland ecosystem in response to the forage-livestock balance in North China[J].Journal of Geographical Sciences, 2021, 31(4): 518-534.

Figures/Tables 10

Table 1

Classification types of grassland degradation and restoration according to changes in vegetation coverage in North China"

Grassland types	Vegetation coverage change	Degradation and restoration types	Grassland types	Vegetation coverage change	Degradation and restoration types
Temperate grassland	Decreased by 10%‒20%	Slight degradation	Alpine grassland	Decreased by 10%‒20%	Slight degradation
	Decreased by 20%‒40%	Moderate degradation		Decreased by 20%‒30%	Moderate degradation
	Decreased by more than 40%	Severe degradation		Decreased by more than 30%	Severe degradation
	Increased by 10%‒20%	Slight restoration		Increased by 10%‒20%	Slight restoration
	Increased by 20%‒40%	Obvious restoration		Increased by 20%‒30%	Obvious restoration
	Increased by more than 40%	Extremely significant improvement		Increased by more than 30%	Extremely significant improvement
Temperate meadow	Decreased by 10%‒20%	Slight degradation	Alpine meadow	Decreased by 10%‒20%	Slight degradation
	Decreased by 20%‒30%	Moderate degradation		Decreased by 20%‒40%	Moderate degradation
	Decreased by more than 30%	Severe degradation		Decreased by more than 40%	Severe degradation
	Increased by 10%‒20%	Slight restoration		Increased by 10%‒20%	Slight restoration
	Increased by 20%‒30%	Obvious restoration		Increased by 20%‒40%	Obvious restoration
	Increased by more than 30%	Extremely significant improvement		Increased by more than 40%	Extremely significant improvement
Temperate desert	Decreased by 5%‒15%	Slight degradation	Alpine desert	Decreased by 5%‒10%	Slight degradation
	Decreased by 15%‒40%	Moderate degradation		Decreased by 10%‒20%	Moderate degradation
	Decreased by more than 40%	Severe degradation		Decreased by more than 20%	Severe degradation
	Increased by 5%‒15%	Slight restoration		Increased by 5%‒10%	Slight restoration
	Increased by 15%‒40%	Obvious restoration		Increased by 10%‒20%	Obvious restoration
	Increased by more than 40%	Extremely significant improvement		Increased by more than 20%	Extremely significant improvement

Table 1

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Figure 1

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Table 5

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Figure 3

Figure 4

Figure 5

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Grassland cover changes	Region	Forest	Cropland	Wetland	Desert	Others
From other ecosystems converted to grassland	Tibet	12.16	0.66	3.23	1.81	0
	Xinjiang	221.43	562.63	755.57	706.52	7.41
	Inner Mongolia	693.09	1733.76	682.47	3668.45	63.07
	Qinghai	20.78	77.02	16.35	304.43	2.14
	Gansu	75.79	891.26	56.38	400.42	4.95
	Total	1023.25	3265.33	1514	5081.63	77.57
From grassland converted to other ecosystems	Tibet	2.67	7.8	615.29	226.4	49.29
	Xinjiang	115.44	11459.14	733.74	190.90	545.71
	Inner Mongolia	1816.39	2924.24	633.75	3122.95	1840.80
	Qinghai	5.63	149.51	429.12	842.29	245.63
	Gansu	380.03	627.20	47.68	138.77	163.94
	Total	2320.16	15167.89	2459.58	4521.31	2845.37

Grassland types	North China			Tibet
Grassland types	Mean (%)	Mean change (%)	Annual trend (%/a)	Mean (%)	Mean change (%)	Annual trend (%/a)
Alpine grassland	18.97	0.11	0.01	15.38	-0.21	-0.06
Alpine meadow	53.35	-0.32	-0.06	45.86	-0.58	-0.13
Alpine desert	7.68	0.34	0.06	6.34	0.29	0.05
Temperate grassland	43.62	1.59	0.28	36.78	-1.16	-0.24
Temperate meadow	75.88	-0.99	-0.19	67.58	-1.31	-0.23
Temperate desert	9.41	0.52	0.10	6.03	-0.34	-0.06
Total	9.40	0.53	0.10	28.50	-0.37	-0.09
Grassland types	Inner Mongolia			Xinjiang
Grassland types	Mean (%)	Mean change (%)	Annual trend (%/a)	Mean (%)	Mean change (%)	Annual trend (%/a)
Alpine grassland	14.69	0.35	0.11	25.77	-0.09	-0.04
Alpine meadow	53.27	1.74	0.35	51.60	-0.76	-0.17
Alpine desert	-	-	-	5.41	0.38	0.07
Temperate grassland	45.03	2.13	0.36	43.71	-1.19	-0.22
Temperate meadow	85.27	0.54	0.07	76.41	-2.82	-0.55
Temperate desert	4.68	0.21	0.05	13.70	0.67	0.13
Total	29.41	1.33	0.23	28.17	-0.11	-0.02
Grassland types	Gansu			Qinghai
Grassland types	Mean (%)	Mean change (%)	Annual trend (%/a)	Mean (%)	Mean change (%)	Annual trend (%/a)
Alpine grassland	17.05	1.19	0.24	29.45	1.14	0.24
Alpine meadow	75.32	-0.05	0.00	59.85	0.01	0.01
Alpine desert	16.67	0.93	0.20	16.75	0.49	0.10
Temperate grassland	40.94	3.34	0.67	37.48	2.03	0.42
Temperate meadow	80.17	0.77	0.15	65.60	0.66	0.16
Temperate desert	7.29	0.75	0.13	9.58	0.77	0.16
Total	35.07	1.19	0.23	35.07	1.19	0.23

Types of grassland degradation and restoration	North China		Tibet		Inner Mongolia
Types of grassland degradation and restoration	Area (km²)	Proportion (%)	Area (km²)	Proportion (%)	Area (km²)	Proportion (%)
Severe degradation	444	0.02	302	0.03	47	0.01
Moderate degradation	5820	0.21	3315	0.38	1454	0.18
Slight degradation	177093	6.51	67514	7.65	66023	8.38
Total degradation	183357	6.74	71131	8.06	67524	8.57
Slight restoration	119270	4.38	15625	1.77	32784	4.16
Obvious restoration	21471	0.79	3266	0.37	2080	0.26
Extremely significant improvement	4879	0.18	629	0.07	170	0.02
Total restoration	145620	5.35	19520	2.21	35034	4.45
Types of grassland degradation and restoration	Xinjiang		Gansu		Qinghai
Types of grassland degradation and restoration	Area (km²)	Proportion (%)	Area (km²)	Proportion (%)	Area (km²)	Proportion (%)
Severe degradation	71	0.01	0	0.00	24	0.01
Moderate degradation	703	0.14	94	0.05	254	0.07
Slight degradation	25994	5.07	5426	3.14	12101	3.32
Total degradation	26768	5.22	5520	3.19	12379	3.40
Slight restoration	53245	10.38	11829	6.84	5748	1.58
Obvious restoration	14118	2.75	1595	0.92	404	0.11
Extremely significant improvement	3869	0.75	138	0.08	72	0.02
Total restoration	71232	13.89	13562	7.84	6224	1.71

Grassland types	North China		Tibet		Inner Mongolia
Grassland types	Mean (g/m²)	Annual trend (g/m²·a)	Mean (g/m²)	Annual trend (g/m²·a)	Mean (g/m²)	Annual trend (g/m²·a)
Alpine grassland	20.23	0.13	19.72	0.10	20.52	0.56
Alpine meadow	49.98	0.33	44.04	0.17	48.19	0.79
Alpine desert	15.79	0.13	16.07	0.20	-	-
Temperate grassland	42.75	0.43	36.41	-0.03	44.70	0.54
Temperate meadow	48.20	0.37	61.75	0.16	55.84	0.54
Temperate desert	14.80	0.15	11.33	0.07	12.38	0.14
Total	33.38	0.27	28.37	0.13	37.62	0.43
Grassland types	Xinjiang		Gansu		Qinghai
Grassland types	Mean (g/m²)	Annual trend (g/m²·a)	Mean (g/m²)	Annual trend (g/m²·a)	Mean (g/m²)	Annual trend (g/m²·a)
Alpine grassland	12.04	-0.02	10.82	0.02	28.78	0.43
Alpine meadow	25.41	-0.23	78.97	0.71	57.69	0.57
Alpine desert	9.41	0.11	13.22	-0.18	22.29	-0.24
Temperate grassland	34.06	-0.12	46.92	0.68	43.37	0.80
Temperate meadow	35.43	0.10	63.57	0.68	37.22	0.35
Temperate desert	17.24	0.14	12.93	0.15	16.80	0.22
Total	23.89	0.04	38.13	0.44	45.99	0.50

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