巴尔喀什湖流域土地利用/覆被变化过程与趋势

doi:10.13866/j.azr.2021.05.28

Abstract

Abstract:

The Balkhash Lake basin is an important transboundary basin spanning China’s Xinjiang region (domestic) and Kazakhstan (overseas). Existing since 1972, the Kapuchagai Reservoir, which is the largest water conservancy project within the Balkhash Lake basin has experienced different stages of ecological change, especially since the collapse of the Soviet Union. This study analyzed three periods in which change occurred and trends in Land Use and Land Cover (LULC) starting from the 1970s, 2005 and year 2015, using the Markov model and other methods. Moreover, the differences between internal and external basin characteristics where identified and compared. The results showed that, in the Balkhash Lake basin, LULC changed; both cultivated and wood lands initially showed a decreasing trend between the 1970s and 2005, then an increasing trend afterward (2005-2015). In contrast, the change processes observed in water areas and unused lands showed a completely opposite trend. In addition, grassland and urban land uses maintained a steady increasing trend. This indicates that later changes in LULC had a greater impact on the overall LULC changes throughout the study period. These changes mainly assume a two-way conversion process, so the change process of the whole river basin was always in equilibrium during the study period. The structure and change process of LULC types outside and inside were different: Internal land use types were more evenly distributed than those located externally, and both the single type and regional LULC variation in trends, and the status index indicated that the domestic change process was more stable than that outside the watershed. However, because the external area accounted for 86% of the entire river basin, it dominated the structure and change process of LULC types in the whole area. This study provides a basis for sustainable land resource management and ecological environment protection in the region.

Key words: Balkhash Lake basin, land use/cover change, land transfer matrix, spatio-temporal changes

LIU Wanru,CHENG Chunbo,LUO Geping,HE Huili. Change processes and trends of land use/cover in the Balkhash Lake basin[J].Arid Zone Research, 2021, 38(5): 1452-1463.

Figures/Tables 8

Fig. 1

Fig. 2

Fig. 3

Tab. 1

Dynamic changes of land use/cover in the Balkhash Lake basin"

		1970s—2005年			2005—2015年			1970s—2015年
		$Δ U$ /%	$Δ S$ /%	$P s$ / $P t$	$Δ U$ /%	$Δ S$ /%	$P s$ / $P t$	$Δ U$ /%	$Δ S$ /%	$P s$ / $P t$
耕地	全流域	-12.58	49.82	-0.25	16.05	63.58	0.25	1.45	81.84	0.02
	境内	30.79	54.32	0.57	5.39	46.05	0.12	37.84	84.35	0.45
	境外	-31.68	47.83	-0.66	25.04	78.36	0.32	-14.57	80.73	-0.18
林地	全流域	-0.29	71.46	0.00	32.58	149.27	0.22	32.19	156.61	0.21
	境内	-0.35	81.27	0.00	4.83	128.04	0.04	4.47	136.08	0.03
	境外	0.00	31.02	0.00	146.95	236.74	0.62	146.95	241.51	0.61
草地	全流域	0.28	6.59	0.04	4.72	27.58	0.17	2.87	29.69	0.17
	境内	-5.69	19.99	-0.28	-3.10	30.00	-0.10	-8.61	34.31	-0.25
	境外	1.36	4.17	0.33	6.05	27.17	0.22	7.49	28.85	0.26
水域	全流域	1.64	11.01	0.15	-5.54	27.98	-0.20	-3.99	29.36	-0.14
	境内	6.56	87.73	0.07	11.10	120.36	0.09	18.39	138.29	0.13
	境外	1.39	6.94	0.20	-6.46	22.81	-0.28	-5.15	23.56	-0.22
城乡建设用地	全流域	17.31	74.38	0.23	40.94	127.38	0.32	65.35	165.68	0.39
	境内	26.08	116.83	0.22	36.98	170.30	0.22	72.70	228.62	0.32
	境外	12.75	52.24	0.24	43.25	102.37	0.42	61.51	132.87	0.46
未利用地	全流域	1.09	4.89	0.22	-13.43	43.15	-0.31	-12.48	43.26	-0.29
	境内	0.18	34.06	0.01	1.59	63.93	0.02	1.77	70.60	0.03
	境外	1.15	2.95	0.39	-14.45	41.78	-0.35	-13.46	41.43	-0.32
整个区域	全流域	-	-	0.13	-	-	0.23	-	-	0.19
	境内	-	-	0.24	-	-	0.08	-	-	0.21
	境外	-	-	0.43	-	-	0.29	-	-	0.28

Tab. 1

Tab. 2

Land use transfer matrix in the Balkhash Lake basin /102 km2"

时段	土地利用类型	耕地	林地	草地	水域	城乡建设用地	未利用地	合计	$∆ U out$
1970s—2005年	耕地	143	0	48	1	4	11	208	65
	林地	0	29	15	0	0	0	45	16
	草地	35	15	2421	9	2	17	2500	79
	水域	1	0	6	248	0	5	260	12
	城乡建设用地	2	0	2	0	10	0	14	4
	未利用地	1	0	15	6	0	1116	1137	22
	合计	182	45	2507	264	17	1150	4164	-
	$∆ U in$	39	16	86	16	7	34	-	-
2005—2015年	耕地	139	0	33	1	7	1	182	43
	林地	0	19	25	0	0	1	45	26
	草地	63	40	2220	18	7	159	2507	287
	水域	1	0	33	220	0	9	264	44
	城乡建设用地	5	0	2	0	10	0	17	7
	未利用地	4	0	311	10	0	824	1150	325
	合计	211	59	2625	250	24	995	4164	-
	$∆ U in$	72	41	405	30	14	171	-	-
1970s—2015年	耕地	124	0	72	1	8	2	208	84
	林地	0	17	26	0	0	1	45	28
	草地	77	41	2191	20	8	162	2500	308
	水域	1	0	32	217	0	10	260	43
	城乡建设用地	4	0	2	0	7	0	14	7
	未利用地	3	0	302	11	0	820	1137	317
	合计	211	59	2625	250	24	995	4164	-
	$∆ U in$	87	42	434	33	17	175	-	-

Tab. 2

Fig. 4

Tab. 3

Land use transfer matrix in Kazakhstan /102 km2"

时段	土地利用类型	耕地	林地	草地	水域	城乡建设用地	未利用地	合计	$∆ U out$
1970s—2005年	耕地	87	0	45	0	2	11	144	57
	林地	0	7	1	0	-	0	9	1
	草地	11	1	2087	8	1	9	2117	30
	水域	0	0	5	240	0	2	247	7
	城乡建设用地	1	-	1	0	8	0	9	2
	未利用地	1	0	7	2	0	1056	1066	10
	合计	99	9	2146	250	11	1078	3592	-
	$∆ U in$	12	1	59	10	3	22	-	-
2005—2015年	耕地	72	0	23	0	2	1	99	26
	林地	0	5	4	0	-	0	9	4
	草地	47	17	1919	16	5	142	2146	227
	水域	0	0	32	214	0	5	250	37
	城乡建设用地	1	0	2	0	8	0	11	3
	未利用地	3	0	296	5	0	775	1078	303
	合计	123	22	2276	234	15	922	3592	-
	$∆ U in$	51	17	356	20	8	147	-	-
1970s—2015年	耕地	76	0	64	0	3	1	144	69
	林地	0	5	4	-	-	0	9	4
	草地	44	17	1891	17	6	142	2117	226
	水域	0	0	30	211	0	5	247	35
	城乡建设用地	1	0	2	0	6	0	9	3
	未利用地	2	0	285	5	0	773	1066	293
	合计	123	22	2276	234	15	922	3592	-
	$∆ U in$	48	17	385	23	9	149	-	-

Tab. 3

Tab. 4

Land use transfer matrix in China /10² km²"

时段	土地利用类型	耕地	林地	草地	水域	城乡建设用地	未利用地	合计	$∆ U out$
1970s—2005年	耕地	56	0	4	1	3	0	64	7
	林地	0	21	14	0	0	0	36	15
	草地	24	14	333	2	1	8	382	49
	水域	1	0	1	8	0	3	13	5
	城乡建设用地	2	0	0	0	3	0	5	2
	未利用地	0	0	8	3	0	58	70	12
	合计	83	36	360	14	6	71	570	-
	$∆ U in$	27	15	27	6	4	12	-	-
2005—2015年	耕地	66	0	10	1	5	1	83	17
	林地	0	14	21	0	0	1	36	22
	草地	16	23	301	2	2	17	360	60
	水域	1	0	2	6	0	5	14	8
	城乡建设用地	3	0	1	0	2	0	6	4
	未利用地	1	0	15	6	0	49	71	22
	合计	88	38	349	15	9	72	570	-
	$∆ U in$	21	24	48	9	6	23	-	-
1970s—2015年	耕地	49	0	8	1	5	1	64	15
	林地	0	12	22	0	0	1	36	24
	草地	33	24	300	3	2	19	382	82
	水域	1	0	2	5	0	5	13	8
	城乡建设用地	3	0	1	0	1	0	5	4
	未利用地	1	0	17	6	0	46	70	24
	合计	88	38	349	15	9	72	570	-
	$∆ U in$	39	25	49	10	7	25	-	-

Tab. 4

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Change processes and trends of land use/cover in the Balkhash Lake basin

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