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1.
张希然  罗旋  陈研华 《土壤学报》1991,28(1):94-102
雷州半岛东海岸潮间带及其紧邻5m等深线以上海涂约211万亩,土壤分1个土类(潮滩土)3个亚类和8个土种。因腹地植被生长较差和成土母质的矿质养分较低,故海涂土壤的有机质和磷、氮含量不高,铜、锌、锰等微量元素含量也低于全国土壤平均水平。土壤含盐量是随质地和滩面水的总盐量的变化而不同,如潮滩沙土由小于0.5%至3.3%。本区地表水量不充裕,但滩面平坦和避浪条件较好,适宜发展海水养殖,部分泥质或沙泥质潮滩土尚有围垦种植的可能。  相似文献   

2.
张希然  罗旋 《土壤》1988,20(2):103-105
海涂土壤是指发育于涨潮淹没,落潮露出的潮间带内的土壤。由于潮间带是海岸带的重要组成部分,因而研究海涂土壤对发展沿海经济和维护海岸带生态平衡都有重要意义。  相似文献   

3.
我国沿海滩涂资源十分丰富,开发利用历史悠久。我国东部黄淮海平原、长江下游平原、珠江三角洲及辽河平原,约有2亿余亩属于古海涂地区,是我国农业、工商业、交通、航运发展的先驱地带,也是近代经济和科学文化发展的重要地区。我国著名的商埠和大、中城市多集中于此。据近期调查,我国沿海理论基准面以上的潮间带面积近3,000万亩,基准面以下至-15米之间共有2亿余亩,更有潮上带未利用的滩涂约700万亩左右。  相似文献   

4.
王繁  周斌  蒋钏 《土壤通报》2006,37(6):1048-1052
作为浙江省海涂土壤资源动态监测系统的子系统,针对浙江省“数字海涂”建设中用户的要求和实际工作的需要,采用ESR I ArcIMS4.0的体系结构和网络发布模块,同时进行了客户端界面二次开发和一些特殊功能的定制,实现了研究区土壤资源、海涂围垦等信息的电子地图网络发布功能。  相似文献   

5.
不同土地利用方式下围垦海涂微生物群落和土壤酶特征   总被引:1,自引:0,他引:1  
利用DGGE技术,从微生物多样性的角度,结合土壤酶活性研究不同农林利用方式对围垦海涂养分特征的影响。结果表明:未利用海涂盐分含量最高,而有机质和碱解氮含量最低;相比于蔬菜地和林地,棉花地和水稻田的有机质、碱解氮、过氧化氢酶和蛋白酶活性更高。四种利用方式土壤的脲酶和磷酸酶活性差异不显著。细菌是土壤中的主要种群,其数量与土壤有机质、碱解氮等养分特征呈显著正相关,表现为水稻田、棉花地>蔬菜地、林地>未利用。DGGE图谱分析结果显示未利用土壤shannon多样性指数最高为2.81,与水稻田、棉花地较为接近,其次为蔬菜地和林地,分别为2.52和2.38。围垦利用引起土壤中的Gaetbulibacter marinus与Gillisia mitskevichiae种属变化。围垦利用后土壤质量优于未利用海涂。相比而言,种植水稻对提高土壤肥力水平,维持土壤质量较为有利。  相似文献   

6.
浙江省海涂资源丰富,建国以来,特别是无产阶级文化大革命以来,海涂的围垦利用发展得很快,并取得了很大成绩。  相似文献   

7.
何守成  董炳荣 《土壤》1986,18(4):181-185
杭州湾南岸拥有大量海涂资源,解放以来已围垦八十三万亩,尚待围垦的海涂面积约有百万亩。但是由于新围海涂地下水位高,矿化度大,土壤盐分重,返盐强烈,围垦后改良土壤速度迟缓,农业产量低而不稳。  相似文献   

8.
江苏沿海潮间带面积广阔,土壤资源丰富,人工地面调查花费大、周期长。本文用卫星遥感的方法,着重就比值处理、非监督分类和监督分类等计算机图象处理方法对江苏沿海潮间带土壤类型识别的效果进行试验和比较。在结合专业知识的基础上,用13个训练类别的监督分类方法可以识别出潮间带7种土壤类型。对分类精度进行了检验,平均相对误差为17.6%。  相似文献   

9.
沿海一些围垦后的海涂土壤,酸性极强,水稻生长困难甚至无收。本研究采用深埋暗管与农业措施相结合的办法,对其进行综合治理。结果表明,治理效果极为显著。水稻长势接近正常,重成酸田山原来的不毛之地变为年亩产达500 kg的中产田,而且,随着洽理措施的不断延续,水稻产量可望逐年提高。  相似文献   

10.
苏北典型新围垦海涂农田盐碱障碍因子特征分析   总被引:3,自引:2,他引:1  
通过对苏北典型新围垦海涂农田(围垦于2005年,种植于2007年)盐碱障碍因子分析发现,农田土壤处于脱盐碱化阶段,其盐分均值为1.78 g/kg,属轻度偏中度盐渍化,但其变幅大,空间变异性强,盐分大值呈斑块状分布于田块中.同时,其pH高,均值达9.83,碱化特征明显.海涂围垦农田土壤盐分与pH的剖面分布均较均匀,垂直变异性弱.离子分析结果显示,海涂围垦农田土壤盐分以NaCl为主,除K+外,土壤可溶性离子按其与盐分和pH的关系大致可以分为两类,一类为Cl-、SO42-、Ca2+、Mg2+、Na+,分别与土壤含盐量呈显著正相关;另一类为CO32-、HCO3-,分别与pH值具有极显著的正相关关系;且同类离子之间互呈显著正相关,而两类离子相互之间呈显著负相关或极弱正相关.K+既与土壤含盐量和pH呈极显著正相关,同时也与除SO42-和Ca2+外的所有离子呈正相关.结合研究区气候特征,在消减新围垦海涂农田土壤盐碱障碍因子的过程中应积极改善土壤的物理性质以增强盐分的淋洗,并重点防止土壤的碱化过程.  相似文献   

11.
施用有机肥是盐碱土改良与培肥地力的有效方式。选鸡粪和木醋液为改良剂,通过土壤培养试验,研究未施肥(CK)、单施鸡粪(CM)、单施木醋液(PA)、鸡粪+木醋液配施(CP)共4个处理对滨海盐碱土化学性质和酶活性的影响。结果表明:与CM相比,CP处理的pH值显著降低0.34个单位,电导率(EC)降低14.52%。与PA相比,施用鸡粪处理(CM和CP)的土壤养分含量和酶活性均显著提高。CP的全氮、有效磷、水溶性有机碳、水溶性有机氮和硝态氮含量较CM分别高出55.32%、103.35%、16.64%、55.68%和45.43%;而土壤α-葡萄糖苷酶、β-葡萄糖苷酶、几丁质酶、亮氨酸氨基肽酶、碱性磷酸酶、多酚氧化酶和脱氢酶活性分别显著增加49.58%、67.85%、40.84%、104.94%、17.66%、62.05%和37.50%。回归分析表明,土壤有机质、全氮、有效磷和水溶性有机碳、氮含量的增加促进酶活性的提高。综上所述,鸡粪与木醋液配施可显著降低盐碱土的pH值,并能显著提高盐碱土养分含量和酶活性。  相似文献   

12.
The clay minerals of more than 200 soil samples collected from various sites of Fujian Province were studied by the X-ray diffraction method and transmission electron microscopy to study their distribution and evolution.Montmorillonite was found in coastal solonchak,paddy soils derived from marine deposit,lacustrine deposit and river deposit,and some lateritic red soil,red soil and yellow soil with a low weathering degree.Chlorite existed mainly in coastal solonchak and paddy soil developed from marine deposit.1.4nm intergradient mineral appeared frequently in yellow soil,red soil and lateritic red soil.The content of 1.4nm intergradient mineral increased with the decrease of weathering degree from lateritic red soil to red soil to yellow soil.Hydrous micas were more in coastal solonchak,paddy soils derived from marine deposit,lacustrine deposit and river deposit.and puple soil from purple shale than in other soils.Kaolinte was the most important clay mineral in the soils iun this province.The higher the soil weathering degree,the more the kaolinite existed.From yellow soil to red soil to lateritic red soil,kaolinite increased gradually,Kaolinite was the predominant clay mineral accompanied by few other minerals in typical lateritic red soil. Tubular halloysite was a widespread clay mineral in soils of Fujian Province with varying quantities.The soil derived from the paent rocks rich in feldspar contained more tubular halloysite.Spheroidal halloysite was found in a red soil and a paddy soil developed from olivine basalt gibbsite in the soils in this district was largely“primary gibbsite” which formed in the early weathering stage.Gibbsite decreased with the increase of weathering degree from yellow soil to red soil to lateritic red soil.Goethite also decreased in the same sequence while hematite increased.  相似文献   

13.
荒漠盐生植物根际土壤酶活性的变化   总被引:12,自引:0,他引:12  
利用根袋法研究了荒漠盐土和灌耕灰漠土中6种不同荒漠盐生植物根际养分和酶活性特征.结果表明:两种土壤中,根际土全氮含量比非根际土高,但全磷却比非根际土低.根际土有效态养分的变化则与全态相反,6种植物的根际土有效氮含量均显著低于非根际土,除芦苇外,根际土有效磷含量均高于非根际土.6种植物中,钠猪毛菜根际土有效氮亏缺最高,有效磷富集也最少.分析测定了根际土和非根际土转化酶、蛋白酶、过氧化氢酶、脲酶、中性磷酸酶和碱性磷酸酶活性及其与土壤养分的关系.结果表明:过氧化氢酶、脲酶和蛋白酶在两种土壤的植物根际表现出相反的变化,荒漠盐土中,根际土3种酶的活性均高于非根际土;而灌耕灰漠土的根际土3种酶活性均低于非根际土.荒漠盐土碱性磷酸酶、过氧化氢酶和转化酶与几种主要养分含量有很强的相关性,较好地体现了荒漠盐土根际的养分状况,也说明盐生植物对荒漠盐土酶活性有较大的影响.  相似文献   

14.
The State of Kuwait has initiated an ambitious national program to establish greenery in 20000 ha of open spaces in inland and coastal areas. Afforestation of intertidal zones with mangrove plants is being considered as a viable option for greening coastal areas. In view of this fact, experimental plantations were established using two ecotypes of Avicennia marina (Bahrain and UAE) and one ecotype of Avicennia germinans (Florida). The study consisted of two 10-year old plantations and two 2-year old plantations. Seedlings established successfully and grew vigorously on some of the locations within the site. Therefore, studies were conducted during 2002-2003 to describe and classify soils that supported maximum mangrove establishment and growth under the harsh arid coastal conditions of Kuwait. For this purpose, eight soil profiles (four each representing areas where seedlings established successfully and grew vigorously and where all seedlings died in the initial stages of establishment) were investigated and classified according to the soil taxonomy. The main soil types observed in the study site were: Typic Aquisalids, Typic/sodic Aquicambids and Calcic Aquisalids. Mangrove growth performance in relation to the landform, soil type and properties of the soil at various depths is discussed in the paper. The plant growth appeared to be the better on the typic Aquisalid soil than that on the Typic/sodic Aquicambid soils. The relative proportions of the coarse sand fraction, occurrence of the anaerobic layer in the profile and the surface layer salinity influenced both the establishment and growth of mangrove plants.  相似文献   

15.
Mycelial fungi in a solonchakous chestnut soil, a sulfate solonchak, and a soda solonchak were studied in the western Lake Baikal basin. The humus content, the degree of salinization, and the composition of salts affected the structure of the micromycete communities. In the chestnut soil, more than half of the species identified were found. The species diversity was higher in the nonsaline and humus horizons. The eolian deposit on the soda solonchak was characterized by the presence of six species of fungi that did not occur in other soil horizons. Their occurrence in the fresh deposit seems to be related to the eolian transfer of fungi with the fine earth from the adjacent areas with the nonsaline soils. The soda solonchak fungi are dominated by the haloalkalitolerant and alkalophilic micromycetes, among which the representatives of the Acremonium (A. antarcticum and A. rutilum) and Verticillum genera and Mycelia sterilia were identified. There was also an alkalophilic ascomycete, which is an indicator of soda salinization??Heleococcum alkalinum. On the whole, the soda solonchak had the lowest number of fungal germs and the lowest species diversity of mycelial fungi among the soils compared.  相似文献   

16.
结合野外调查取样,采用Bremner法测定下辽河平原两种类型(草甸土型和滨海盐渍土型)水稻土有机氮组分含量。结果表明:1两种类型水稻土均以酸解氮为主体。草甸土型水稻土酸解氮含量显著高于滨海盐渍土型水稻土(P0.01),其分配比例则显著低于滨海盐渍土型水稻土(P0.01)。2两种类型水稻土酸解各组分氮含量及其分配比例的分布规律不同,其差异因酸解氮组分的不同而异。草甸土型水稻土表现为未知态氮氨态氮氨基酸态氮氨基糖态氮,滨海盐渍土型水稻土则表现为氨基酸态氮未知态氮氨态氮氨基糖态氮;草甸土型水稻土酸解氨态氮与氨基酸态氮总量及其分配比例显著低于滨海盐渍土型水稻土(P0.01),酸解未知态氮含量及其分配比例则显著高于滨海盐渍土型水稻土(P0.01)。3两种类型水稻土酸解氮含量均与其土壤有机碳、全氮含量呈显著正相关(P0.01)。因此,该地区两种类型水稻土有机氮组分含量及其分配比例的显著差异是影响土壤氮素有效性的重要因素。  相似文献   

17.
The stocks of organic carbon and mean rates of the CO2 emission during the growing season (May–September) and the entire year were estimated in a sequence of grass ecosystems along the transect encompassing chestnut and meadow-chestnut steppe soils, marsh and meadow alluvial soils, and a haloxerophytic community on a typical solonchak. The total stocks of organic carbon comprised 6.17–9.70 kg С/m2 in steppe, 7.41–10.04 kg С/m2 in floodplain, and 4.74 kg С/m2 in haloxerophytic ecosystems. The portion of humus carbon in the upper 50-cm-thick soil layer comprised 79–92% of the total carbon stock. The mean daily CO2 emission (С–CO2/(m2 day)) from alluvial soils was moderate (3.3–4.9) or low (1.5–2.5). The dependence of the CO2 emission on the moistening of steppe soils, temperature of alluvial soils, and temperature and moistening of solonchak was revealed. In comparison with the CO2 emission from the zonal chestnut soil, its mean values during the growing season and the entire year were 1.2 times higher for the meadowchestnut soil, 3.3 times higher for the marsh alluvial soil, 2.3 times higher for the meadow alluvial soil, and 1.7 times higher for the solonchak. The portion of the CO2 emission beyond the growing season in the mean annual emission averaged 19.8–24.2% and depended on the type of grass ecosystem and on weather conditions of particular years. The sink of carbon in the grass ecosystems exceeded carbon emission, especially in the steppe ecosystems.  相似文献   

18.
红树林湿地土壤CH4产生率及其土壤理化因素影响的研究   总被引:8,自引:0,他引:8  
本文对海南东塞港和厦门西港的两个红树林(白骨壤群落)的土壤CH4产生率及其土壤理化因子的影响进行了研究。海南红树林和厦门红树林的土壤CH4产生率平均值分别为3.59和11.59ng/gd,高于海岸光滩的值不(1.62ng/kg)而低于红树林伐迹地的值(48.96ng/gd),说明红树林植对显地CH4的产生有促进作用,且这种促进作用主要是通过根系腐解来实现的。相隔约5个纬度的两个红树林的土壤CH4产  相似文献   

19.
近19年江苏海岸带地区土地利用变化特征   总被引:2,自引:1,他引:2  
海岸带地区因其拥有丰富的水土资源成为人类生产活动最为集中的区域之一,然而近几十年来,由于人类强烈的开发利用活动导致海岸带地区土地利用类型发生显著改变。从时间序列上选取1995年、2002年、2009年、2013年四期遥感影像数据,借助RS和GIS技术对近19a江苏海岸带地区土地利用变化及其服务功能价值开展研究,以期为当地土地资源的合理开发利用、土地利用结构调整以及实现人地的和谐统一提供参考依据。结果表明:(1)从土地利用类型构成来看,耕地是江苏海岸带地区最为主要的土地利用类型,其次为人工塘,而林地、草地和滩地面积相对较小;(2)从土地利用类型面积变化趋势来看,研究区土地利用类型变化集中体现为耕地、水体、滩涂的减少和建设用地、人工塘面积的增加;(3)从土地利用类型转移来看,各研究时段土地利用类型转移有所不同,总体来看,耕地、建设用地、人工塘三种土地利用类型间的转移更为普遍与频繁,相互转移量大;水体主要与滩涂发生相互转换;而耕地则是林地与草地的主要转移目标和来源;(4)近19a来,江苏海岸带地区生态系统服务总价值逐渐减少,且减少速率明显加快。  相似文献   

20.
Abstract

Soil salinization and sodication affect large areas of agricultural land in the world. Amelioration of these soils to make them suitable for agricultural production depends on understanding sodium dynamics and chemical interactions governing nutrient availability. Three locations in eastern Croatia were characterized to the 5‐m depth. The two solonetz‐solonchak soils were alkaline, whereas the solonetz soil had near‐neutral A/E horizon and alkaline deeper horizons. Electrical conductivity of the saturated extract (ECe) was greater than 4 dS m?1 in the top horizons in the solonetz‐solonchak soils. The solonetz soil had 2.8–4.7 dS m?1 in shallow A/E, CG, and G horizons and up to 6.3 dS m?1 below 1.5 m. Highly alkalinized sodic horizons (exchangeable sodium percentage, ESP >20) had 24–47% Ca2+ and 27–33% Mg2+ on the cation exchange complex. Sodium adsorption ratio (SAR) was high (18–26) in the P horizon and even more so in Bt,na horizon (35–36) of solonetz‐solonchak soils. A strong negative exponential relationship existed between soluble Ca2+ and SAR (SAR increased greatly when Ca2+ dropped to around 3 mg dm?3). An increase in pH to greater than 8.4 resulted in an exponential increase in SAR. Leaching of Na+ with successive volumes of water was similarly effective for the P and Bt,na horizons in the solonetz‐solonchak soils, but SAR remained greater than 15 even after six successive cycles of leaching. In conclusion, extensive amelioration of tested soils with gypsum and leaching will be required to overcome poor physical and chemical characteristics caused by various degrees of alkalization and sodication to bring these soils into production.  相似文献   

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