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1.
基于水量平衡及水源涵养深度计算方法,研究了2000 ? 2018年甘肃祁连山国家级自然保护区水源涵养深度的时空变化及其驱动力。结果表明,多年平均水源涵养深度为34.23 mm,水源涵养总量为8.56 × 108 m3·a?1。林地、草地和湿地的水源涵养深度显著高于耕地和未利用地(P < 0.05)。多年平均水源涵养深度的空间分布表现为中东部高而西北部低,水源涵养深度越高其年际变幅越大。研究时段内水源涵养深度总体呈不显著变化,显著增加区主要集中在中高海拔区,显著减少区主要分布在低海拔区(P < 0.05)。水源涵养深度的时空变化主要受降水量和土地覆盖类型的影响,其次是叶面积指数和温度。水源涵养深度与降水量显著正相关(P < 0.05),与叶面积指数和气温负相关。建议将保护区中东部设为水源涵养保护优先区,强化对林地、草地和湿地的保护。在气候暖湿化背景下,未来保护区水源涵养深度将保持稳定态势。 相似文献
2.
承德市武烈河流域是京津冀水源涵养功能区的重要组成部分,对国家可持续发展议程创新示范区的建设具有重要意义.本研究基于InVEST模型估算了1990-2018年武烈河流域的水源涵养量时空分布特征.结果表明:1)当Zhang系数为3.7时,模拟效果最佳,29年来,研究区多年平均水源涵养深度为83.85 mm,平均水源涵养总量为2.18×108 m3,总体呈微弱减小的变化趋势;2)研究区水源涵养深度与降水量显著正相关(P<0.05),与潜在蒸散发量显著负相关(P<0.05),与气温负相关,但不显著(P>0.05);3)各土地利用类型单位面积变化对水源涵养量的影响强度依次为林地、草地、耕地、建筑用地;4)通过情景模拟法得出,气候是研究区水源涵养量变化的主导因素,土地利用变化对水源涵养的抑制作用逐渐增强. 相似文献
3.
承德市武烈河流域水源涵养功能的时空特征 总被引：1，自引：0，他引：1
《草业科学》2021,(6)
承德市武烈河流域是京津冀水源涵养功能区的重要组成部分,对国家可持续发展议程创新示范区的建设具有重要意义。本研究基于InVEST模型估算了1990-2018年武烈河流域的水源涵养量时空分布特征。结果表明:1)当Zhang系数为3.7时,模拟效果最佳,29年来,研究区多年平均水源涵养深度为83.85 mm,平均水源涵养总量为2.18×108 m~3,总体呈微弱减小的变化趋势;2)研究区水源涵养深度与降水量显著正相关(P 0.05),与潜在蒸散发量显著负相关(P 0.05),与气温负相关,但不显著(P 0.05);3)各土地利用类型单位面积变化对水源涵养量的影响强度依次为林地、草地、耕地、建筑用地;4)通过情景模拟法得出,气候是研究区水源涵养量变化的主导因素,土地利用变化对水源涵养的抑制作用逐渐增强。 相似文献
4.
基于InVEST模型的张家口市水源涵养功能时空差异分析 总被引：1，自引：0，他引：1
《草业科学》2020,(7)
张家口市是"首都水源涵养功能区和生态环境支撑区",对维护区域生态安全具有重要作用。本研究基于InVEST年产水模型,估算了张家口市1981–2015年的产水量、水源涵养量,并对其时空变化特征进行分析。结果表明:1)张家口市多年平均产水深度为42.51 mm,多年平均水源涵养深度为18.16 mm;2) 35年来,张家口市产水量呈微弱上升趋势,水源涵养量呈微弱下降趋势,最高值均出现在1995年,最低值均出现在1993年;3)产水深度及水源涵养深度具有明显的空间差异,且分布相似,表现为康保、宣化周围区县增加,沽源、蔚县等减少;4)降水是张家口市产水量、水源涵养量变化的主要影响因素,其次为土地利用方式;5)张家口市多年平均产水量以草地和耕地为主,水源涵养量以草地为主。 相似文献
5.
《草业科学》2020,(7)
基于InVEST模型,定量评价张北坝上水源涵养功能,识别水源涵养重要性等级,分析其空间分布特征,为提升张北县水源涵养功能提供科学依据。结果表明:1)张北县水源涵养总量为1.42×108 m3,平均深度为33.98 mm,空间分布不均。水源涵养量与降水量呈正比,与潜在蒸散发呈反比。2)林地的水源涵养能力最强,旱地的水源涵养总量最大。3)水源涵养重要性主要为中等重要,该区域人类活动集中、旱地分布广、水源涵养量低。水源涵养极重要区分布于东部、南部以及中部稀疏的林地和草地。4)张北县水源涵养量和重要性低的主要原因在于林地和草地稀疏生长、旱地分布广。建议在保留适当旱地规模的基础上,继续实施退耕还草还林工程,提高水源涵养能力。 相似文献
6.
土地利用是生态系统水源涵养功能的一个重要驱动力。随着全球气候变化的发展，准格尔旗水源短缺问题日益严重。本研究基于FLUS模型预测自然发展、城市发展与生态保护情景下2040年准格尔旗土地利用变化，运用InVEST模型分析了准格尔旗水源涵养的时空变化，结果表明：三种情景下FLUS模型的Kappa系数为0.87,0.88和0.83,均大于0.80,说明FLUS模式能很好地模拟研究区的土地演替。运用InVEST模型得出2040年城市发展情景水源涵养量最低为2.98×108 m3,生态保护情景水源涵养量最多为3.37×108 m3。全旗的水源涵养量总体表现为“东高西低”“北高南低”的基本分布模式。根据各土地利用类型单位面积水源涵养能力的差异，其强度按以下顺序排列：草地>林地>耕地>水域>建设用地>未利用土地。通过对准格尔旗的土地利用状况和水源涵养功能的研究，能够为规划生态保护区提供管理建议，为社会经济发展提供理论支撑。 相似文献
7.
祁连山国家级自然保护区土地利用时空变化及与气候因子关系研究 总被引：1，自引：0，他引：1
土地利用类型变化是植被变化最直接的表现形式。祁连山是我国西部地区重要的水源涵养区,生态环境比较脆弱,研究区域内土地利用时空变化对区域生态环境保护具有重要意义。本文基于2000—2018年土地利用类型数据,分析祁连山土地利用时空变化特征及影响因子。结果表明：草地、林地、未利用地是研究区主要的土地利用类型,耕地、城乡、工矿居民用地、水域面积较小;2000—2018年间祁连山范围内草地、林地、水域面积增加,未利用地面积减少,且2005—2010年期间土地利用类型变化最为明显;2000—2018年期间祁连山区域草地覆盖度增加,中、高覆盖草地面积增加,低覆盖草地面积较少;2000—2018年土地利用类型变化主要发生在祁连山西部地区,主要为草地与未利用地之间的相互转化。草地变化受降水、相对湿度的影响较大。 相似文献
8.
土地利用类型影响土壤团聚体稳定性及碳氮分布,进而改变土壤碳氮循环过程.本研究对热水河小流域草地、灌丛和林地3种不同林草恢复措施下0?100 cm剖面土壤团聚体、碳氮及其他理化性质进行了系统研究,以探索适宜的林草恢复措施.结果表明:不同林草恢复对侵蚀区土壤团聚体分布、稳定性和碳氮特征具有显著的影响.在0?10、10?30和30?60 cm各土层中,草地>2 mm粒级团聚体含量显著大于灌丛和林地(P<0.05),而在60?100 cm土层中,则表现为灌丛>林地>草地(P<0.05);土壤团聚体重量平均直径(mean weight diameter,MWD)和几何平均直径(geometric mean diameter,GMD)分布趋势与大于0.25 mm粒级团聚体(the ratio of>0.25 mm aggregate,R0.25)相似.在0?10和10?30 cm土层中,草地总氮和有机碳含量显著大于灌丛和林地(P<0.05);但随土层加深,草地深层土壤碳氮含量分布减少,在30?60和60?100 cm土层中,土壤总氮和有机碳含量分布趋势表现为灌丛>林地>草地(P<0.05);此外,草地碳氮计量比在3种土地利用中始终处于较低水平.土壤团聚体稳定性、碳氮含量与土壤pH、土壤机械组成等土壤性质密切相关.MWD与pH极显著正相关(P<0.01),GMD与pH和粉粒含量显著正相关(P<0.05),而R0.25与土壤机械组成极显著相关(P<0.01),与总氮和有机碳含量则显著相关(P<0.05);土壤总氮和有机碳含量与pH和粉粒含量极显著负相关(P<0.01),与砂粒含量极显著正相关(P<0.01).本研究结果表明,在表层土壤中草地具有较好的稳定土壤结构,具有稳固碳氮的作用,而在较深土层中,灌丛和林地等植被恢复措施的团聚体稳定性较强,碳氮含量也较高.本研究为干热河谷地区的生态修复提供了数据支持. 相似文献
9.
托木尔峰国家级自然保护区台兰河上游不同海拔草地土壤持水能力研究 总被引：3，自引：0，他引：3
为探究托木尔峰国家级自然保护区不同海拔草地土壤水源涵养能力的空间变化,本研究通过野外调查、土样采集及室内分析,对托木尔峰自然保护区台兰河上游河谷不同海拔草地表层土壤持水能力进行研究。结果表明:研究区草地土壤物理性质随海拔高度的增加表现有所不同,其中平均土壤含水量、非毛管孔隙度、毛管孔隙度和总孔隙度均与海拔表现出显著的正相关关系,随海拔高度的上升均呈现出不断增加的趋势;土壤容重则与海拔存在着极显著的指数负相关关系(R2=0.881 7),即随着海拔高度的增加,土壤容重呈减小趋势。研究区不同海拔草地土壤的水源涵养能力不同,其中最大持水量、非毛管蓄水量和毛管持水量的大小顺序均为山地栗钙土山地棕钙土山地棕漠土,即随海拔高度的增加而增大;土壤涵蓄降水量与有效涵蓄量的大小顺序均为山地棕漠土山地棕钙土山地栗钙土,随海拔高度的增加而呈下降趋势。海拔高度与放牧及人为活动的干扰强度是导致研究区草地土壤水源涵养功能差异显著的重要因子。 相似文献
10.
围栏封育对三江源区退化高寒草地植物光合作用及生物量的影响 总被引：2，自引：0，他引：2
在青海省果洛藏族自治州玛沁县选取4个不同退化程度的天然草地,以围栏封育和围栏外自由放牧草地作比较,调查草地围栏内外不同退化程度的植物群落组成和生物量,分别测定各植物群落光合速率和叶面积指数。结果表明:植物群落光合速率、叶面积指数和生物量随着退化程度的加剧而减小,围栏内植物群落的光合速率和叶面积指数和生物量均大于围栏外的植物群落(P<0.05);不同退化程度下围栏内外植物群落的光合速率、叶面积指数与生物量之间成显著正相关关系(P<0.05),且围栏内植物这3项指标间的相关系数大于围栏外植物(除光合速率和叶面积指数间的相关系数外)。围栏封育可以改变草地植物群落的光合作用速率和叶面积指数,有利于退化草地植物的生物量积累和植被恢复。 相似文献
11.
Slocombe JO McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(10):323-327
In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal.
Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection.
相似文献12.
13.
Slocombe JO McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(9):347-350
In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario.
Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously.
相似文献14.
15.
Slocombe JO Villeneuve A 《The Canadian veterinary journal. La revue veterinaire canadienne》1993,34(10):630-633
In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium. 相似文献
16.
Owen J Slocombe D McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1986,27(9):324-328
In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%).
Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada.
相似文献17.
Slocombe JO McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(6):504-508
In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%). 相似文献
18.
In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated.
Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively.
相似文献19.
Slocombe JO McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1988,29(8):641-646
In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%). 相似文献
20.
Owen J Slocombe D McMillan I 《The Canadian veterinary journal. La revue veterinaire canadienne》1987,28(8):491-495
In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%).
Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada.
相似文献