许艳
, 濮励杰, 张润森
XU Yan, PU Lijie, ZHANG Runsen
通讯作者:
收稿日期: 2017-04-10
修回日期: 2017-08-8
网络出版日期: 2017-11-20
版权声明: 2017 《地理学报》编辑部 本文是开放获取期刊文献，在以下情况下可以自由使用：学术研究、学术交流、科研教学等，但不允许用于商业目的.
基金资助:
作者简介:
作者简介：许艳(1986-), 女, 江苏滨海人, 博士后, 主要从事土地利用与规划研究。E-mail: xuyanxiaozz@126.com
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摘要
淤涨型沿海滩涂作为中国重要湿地和耕地后备资源,承担着生态保护、社会保障、经济发展等多重服务功能。选取江苏中部淤涨型滨海滩涂开展实证分析,分析围垦年限为0~40年滩涂垦区耕地质量因子空间差异,采用“时空代换”方法揭示滨海滩涂围垦后耕地质量的演变趋势,为沿海滩涂围垦区耕地资源可持续利用提供决策参考。结果表明：江苏中部沿海滩涂土壤总体呈现盐碱度高、养分贫瘠等特征且土壤理化性质变异程度高,土壤质地呈现显著南北和陆海梯度特征。滩涂垦区围垦初期地形、植被状态和围垦后滨海滩涂转变为耕地路径对耕地质量演变趋势均具有重要影响。沿海滩涂转为耕地路径由垦区自然条件、开发主体、开发规模等因素共同作用,江苏中部沿海滩涂转为耕地路径已从“盐生植被→养殖水体→耕地”转变为“盐生植被→耕地”,该转变缩短了滩涂转为耕地的周期,但同时也带来围垦滩涂撂荒闲置现象。围垦后沿海滩涂土壤逐步向耕地土壤转变,耕地质量因子演变趋势可分为四种：上升型,如土壤全磷、有效磷、粘粒含量;下降型,如土壤砂粒含量;下降—上升型,如有机质、全氮、碱解氮和CEC;上升—下降型,如土壤盐分和pH。围垦初期,滩涂土壤脱离海水环境,土壤有机质发生矿化过程呈现下降趋势,土壤盐分和pH受到蒸发和蒸腾作用急剧上升;围垦中期,受到人类耕作作物秸秆等有机物输入以及施肥的影响,土壤有机质、养分等呈现上升趋势,土壤盐分和pH呈现下降趋势;围垦后期,耕地质量因子受到耕作管理影响存在一定幅度的波动,由于沿海滩涂垦区耕地形成时间短,耕地质量对耕作管理等因素敏感度高。
关键词：
Abstract
Coastal prograding tidal flats are important wetlands and reserve resources of cropland in China, which provide the services of ecological protection, society security, and economic development. Taking the reclamation zones on the prograding coast of Jiangsu as a case study, this paper analyzed soil quality at the reclamation zones with a duration of 0-40 years to indicate the evolution of cropland quality following reclamation for sustainable use of cropland, by using the method of "space for time substitution". The results show that cropland soils had high salinity but low nutrients. The variation of soil physical and chemical properties is high in the coastal reclamation zones, and the soil particle sizes had obvious gradients of North-South and Land-Sea. The factors such as topography, vegetation status, and the path of tidal flats to cropland had significant impacts on cropland quality evolution following coastal reclamation. The path of tidal flats to cropland were jointly decided by physical condition of reclamation zones, development entity, and development scale in the coastal area of Jiangsu. The cropland trajectories have changed from "halophytes→aquaculture pond→cropland" to "halophytes→cropland" in the central part of the province's coastal area. This change shortened the period of tidal flats to cropland, but led to idle tidal flats after reclamation. The soils of coastal tidal flats have gradually transferred into soils of cropland. The changing trends of soil properties were divided into four types. The first one was the type of increase, such as soil total phosphorous, available phosphorous, and clay content. The second one was the type of decrease, such as sand content. The third one was the type of increase then decrease, such as soil salinity and pH. The fourth one was the type of decrease then increase, such as soil organic matter, total nitrogen, available nitrogen, and capacity of exchange cations. At the initial period of reclamation, soil organic matter showed a declining trend because of the process of mineralization. The soil salinity and pH increased due to transpiration and evaporation. At the middle period of reclamation, soil organic matter and nutrients increased because of the fertilization and organic matter input via human cultivation. Soil salinity and pH decreased as a result of precipitation and water resource facilities. At the later period of reclamation, the factors of soil quality fluctuated under the effect of cultivation management. The quality of cropland at the reclamation zones was fragile and sensible to cultivation management, because of the relatively short history of coastal reclamation.
Keywords：
中国海岸带北起辽宁省鸭绿江,南达广西壮族自治区的北仑河口,长达18000 km,土地资源丰富。海涂资源主要分布在大河三角洲平原海岸和华南海岸的一些港湾内,面积高达235万hm2,每年仍以2~3万hm2的速度淤涨[1]。随着围垦技术的提高,滨海滩涂围垦强度和广度均达到空前规模,滩涂围垦一方面加快了滨海湿地空间萎缩和功能退化,另一方面增加了人类生存空间,缓解人地矛盾[2-3]。国内外学者对海岸带滩涂自然环境演变[4-5]、盐生植被演替[6-9]、土地利用变化[3, 10-14]等方面做了大量的研究。沿海滩涂围垦后土壤理化性质的变化也逐步受到关注[15-22]。大量学者通过“时空代换”方法揭示滨海滩涂围垦耕地质量演变过程[16, 18-20, 23],但时间尺度较大,多为百年和近百年[19, 24],对于沿海滩涂围垦后滩涂土壤质量演变关键期（0~40年）的演变过程尚且模糊。
江苏沿海滩涂面积达50万hm2,以粉砂淤泥质海岸为主,约占中国滩涂总面积的四分之一,虽然已无巨量泥沙来源,受到自身海岸侵蚀和海底泥沙影响,江苏中部海岸线每年仍以较快速度向外海淤长[1, 4]。由于国家和江苏省对江苏沿海地区耕地后备资源战略定位等,耕地一直是江苏海岸带主要土地利用类型之一[14]。1951-2015年江苏沿海滩涂围垦面积高达33.46万hm2,增加农用地12.67万hm2,2009年《江苏沿海地区发展规划》规划未来10年江苏沿海面临前所未有的高强度、大规模的围垦活动,将新增耕地10.8万hm2。因此,本文选取江苏中部滨海滩涂开展实证分析,在围垦年限为0~40年的滩涂围垦区采集耕地土壤样品并开展实验分析,试图揭示滩涂围垦后耕地质量因子演变趋势,为淤涨型滨海滩涂围垦耕地可持续利用提供信息支持。
江苏海岸线长954 km,约占全国5%,然而江苏沿海滩涂资源却占全国的25%左右。江苏沿海经过13个县市,介于31°33′N~35°07′N、119°21′E~121°55′E之间,东临黄海,受季风气候控制,处于北亚热带向暖温带过渡地带,兼受海洋性和大陆性气候双重影响。苏北灌溉总渠以南,沿海全年太阳总辐射能量达110~118 k Cal/cm2,年日照量2100~2400 h,年平均气温为14~15 ℃;年平均降水量为1000~1100 mm[25]。江苏沿海滩涂围垦区土壤类型主要以滨海盐土为主。
江苏沿海滩涂围垦历史悠久,围垦空间上,盐城市围垦面积最大,南通市和连云港市较少[2]。江苏沿海滩涂围垦多为鱼鳞式的圈围为主,滩涂围垦重心不断向东南方向转移（图1）。江苏沿海滩涂围垦区土地利用方式近代主要以垦植业和盐业为主;20世纪50-60年代,治水兴垦,江苏沿海掀起创办农场和盐场热潮;20世纪70年代,基本是传统的“围垦—养垦—开垦”的利用方式;80、90年代江苏沿海滩涂围垦才逐步摆脱传统的开发方式,走上粮棉生产、盐业和水产养殖为主,农、林、牧、渔、盐、港等综合开发的模式[26]。总体来看,江苏沿海滩涂围垦用途主要以农业生产、水产养殖、国营盐场为主[2]。
本文研究的31幅Landsat TM和OLI遥感影像数据,主要来源于中国科学院计算机网络信息中心开发的地理空间数据云（http://www.gscloud.cn/）。选取1986-2016年年初遥感影像进行人工判读,将土地利用类型分为耕地（Cropland, C）、养殖水体（Aquaculture pond, A）、盐生植被（Halophyte vegetation, H）和光滩（Bareland, B）。耕地质量数据来源于野外土壤采样和实验室分析。垦区内农村道路、沟渠、河流水面、农村居民点矢量数据来源于江苏省国土资源厅2015年土地利用变更调查数据库。
江苏沿海围垦年限为0~40年垦区的土壤类型为滨海盐土[26],为了研究滩涂围垦后耕地土壤质量演变过程,本文在1979年（垦区N和O）、1981年（垦区M）、1984年（垦区L）、1986年（垦区K）、1989年（垦区G）、1990年（垦区I）、1997年（垦区H和G）、1998年（垦区F）、2001年（垦区E）、2005年（垦区D）、2006年（垦区C）、2009年（垦区B）和2012年（垦区A）这15个垦区采集表层土壤（0~20 cm）81个（图1）。采样时间为2016年5月26-31日以及6月3-8日,时处小麦收获期。采样期间东台市小雨,大丰区多云。耕地种植作物为小麦,耕地轮作方式多为水稻—小麦,新围垦区以旱作为主。所有土壤带回实验室后经自然风干,过2 mm筛后保存备用。
本文测定了12个土壤重要的理化指标：土壤有机质（OM）、全氮（TN）、全磷（TP）、碱解氮（AN）、有效磷（AP）、阳离子交换量（CEC）、土壤含水量（W）、土壤盐分（EC）、土壤pH、土壤砂粒含量（Sand,> 0.02 mm）、粉粒含量（Silt,0.002~0.02 mm）和粘粒含量（Clay,< 0.002 mm）。土壤有机质采用外加热硫酸—重铬酸钾氧化方法;土壤全氮采用硫酸—重铬酸钾氧化—碱化蒸馏方法;碱解氮采用氧化镁扩散—硼酸吸收;有效磷采用碳酸氢钠浸提—分光光度法;阳离子交换量采用氯化铵交换—氧化镁碱化—蒸馏—硼酸吸收方法;土壤含水量采用烘干法;土壤盐分和土壤pH均采用1:5土水比浸提液,分别用梅特勒托—利多电导率仪和pH计测定。土壤颗粒组成采用比重计法测定[27]。
3.3.1 “时空代换”方法 在物理学领域中,为了认识热现象规律,无需了解每个分子每一时刻的运动状态,而只需研究总体的宏观运动规律,用概率论的方法描述总体的平均行为。“各态遍历性”（ergodicity）的概念用于刻画粒子的空间分布状态,即假设单个粒子运动服从平稳随机过程,某一空间分布状态等同于某一时刻有大量粒子组成的总体在该空间中的分布状态。该理论后来被引入到生态学领域和地貌演化的研究中[28]。年代序列和时空代换（Space-for-time substitutions）是研究多时间尺度植物演替和土壤发生过程的重要和必要方法之一[29]。该方法适用于具有类似演变轨迹、具有不同年龄的研究区,目前也广泛应用于土壤研究领域[30-31],揭示土壤长期演化过程。
3.3.2 统计分析方法 单因素方差分析（One-way ANOVA）用于完全随机设计的多个样本均数间的比较,本文运用SPSS 23软件,对不同年限垦区土壤数据进行单因素方差分析比较组间差异显著性水平。典范对应分析（CCA）是将对应分析和多元回归模型相结合,揭示多元变量及其与环境因子的关系。本研究基于R语言软件运用CCA分析滩涂围垦区耕地土壤样品、土壤理化性质和滩涂围垦年限（Reclamation duration, RD）、耕作年限（Cropland duration, CD）、光滩年限（Bare land duration, BD）、盐生植被年限（Halophyte duration, HD）、养殖年限（Aquaculture duration, AD）、至海岸线距离（Distance to sea, SD）、垦区道路面积占比（Road proportion, RP）、居民点面积占比（Village proportion, VP）、水体面积占比（Water proportion, WP）以及垦区面积（Area）的排序关系。
江苏中部沿海滩涂围垦区耕地土壤基本理化性质如表1所示。按照全国土壤养分标准来看,江苏中部沿海滩涂围垦区土壤养分（有机质、全氮、全磷等）平均水平一般处于第四等级,波动于第三~第六等级,土壤养分贫瘠,且土壤养分变异程度处于中等水平,其中土壤速效磷变异程度较高。根据美国盐分实验室对盐碱土划分标准,土壤盐分平均值属于非盐土,然而土壤盐分波动于非盐土和强盐土之间,土壤盐分变异程度较高。从国际制土壤质地分类来看,江苏中部沿海滩涂土壤属于壤土和粘壤土两个类,土壤粘粒和粉粒占比变异程度高,土壤砂粒占比变异相对较小。江苏中部沿海滩涂围垦区土壤呈碱性,波动于中性至碱性之间。因此,江苏沿海中部滩涂围垦区耕地土壤呈现养分贫瘠、盐碱度高等特征,且变异程度较大。
表1 滩涂围垦区耕地表层土壤理化性质统计值
Tab. 1 Statistics of cropland soil physical-chemical properties at the coastal reclamation zones
| 单位 | 最小值 | 最大值 | 平均值 | 标准差 | 变异系数 | 偏度 | 峰度 | |
|---|---|---|---|---|---|---|---|---|
| OM | % | 0.57 | 2.81 | 1.36 | 0.48 | 0.35 | 0.82 | 0.34 |
| TN | ug/g | 387.00 | 1636.00 | 822.41 | 277.57 | 0.34 | 0.93 | 0.39 |
| TP | ug/g | 625.00 | 1342.00 | 879.00 | 179.27 | 0.20 | 0.43 | -0.63 |
| AP | mg/kg | 2.64 | 89.20 | 26.01 | 19.67 | 0.76 | 0.96 | 0.18 |
| AN | mg/kg | 16.70 | 111.00 | 55.77 | 22.74 | 0.41 | 0.37 | -0.64 |
| CEC | mmol/kg | 28.70 | 151.00 | 65.47 | 21.63 | 0.33 | 1.50 | 3.53 |
| 盐分 | us/cm | 80.80 | 1456.00 | 272.49 | 228.15 | 0.84 | 2.36 | 8.42 |
| pH | 无量纲 | 7.75 | 8.96 | 8.25 | 0.25 | 0.03 | 0.64 | 0.39 |
| 含水量 | % | 7.86 | 46.18 | 32.93 | 4.85 | 0.15 | -1.40 | 8.70 |
| 粘粒 | % | 5.99 | 25.99 | 10.93 | 3.84 | 0.35 | 1.93 | 4.24 |
| 粉粒 | % | 6.00 | 44.00 | 27.27 | 8.56 | 0.31 | -0.10 | -0.50 |
| 砂粒 | % | 37.01 | 85.01 | 61.80 | 11.31 | 0.18 | -0.38 | -0.36 |
从中国海岸带空间分布来看,江苏中部沿海滩涂围垦区有机质含量介于0.57%~2.81%,略高于渤海湾和辽河口滩涂,与江苏如东有机质含量差异不大,比崇明岛、杭州湾、慈溪、闽江口、珠江口滩涂有机质含量低,主要原因是受到气候因素的影响,气候温暖地区滩涂生物量相对较大（表2）,与其他学者研究一致[33]。土壤全氮的含量空间分布与有机质类似。江苏中部沿海地区滩涂土壤磷含量与江苏如东、崇明岛差异不大,但比辽河口、渤海湾、杭州湾、珠江口相对较高,主要原因在于磷的原生矿物主要存在粗颗粒中,而苏北滩涂、长江口等滩涂沉积物以砂粒和粉砂为主,粘粒含量较小。
表2 中国沿海滩涂土壤理化性质特征比较
Tab. 2 Comparision of soil physical-chemical properties at the coastal tidal flats, China
| OM | TN | TP | 粘粒 | 粉粒 | |
|---|---|---|---|---|---|
| % | ug/g | ug/g | % | % | |
| 本研究 | 0.57~2.81 | 0.39~1.64 | 0.62~1.34 | 6~26 | 6~44 |
| 辽河口[34, 35] | 0.1~2.27 | 0.8~3.43 | 0.36~0.66 | 12.83~26.12 | 66.83~72.29 |
| 渤海湾[36, 37] | 0.06~1.77 | 0.07~0.76 | 0.41~0.71 | 0~26.0 | 60.1~84.7 |
| 江苏如东[38-40] | 0.06~2.11 | 0.08~1.84 | 0.46~1.39 | 6.2~13.3 | 7.5~36.6 |
| 崇明岛[19, 41] | 0.98~4.20 | 0.59~2.12 | 1.319 | 6.5~13.3 | 54.4~76.1 |
| 杭州湾[16, 42] | 0.27~6.21 | 0.25~1.05 | 0.33~0.67 | 5~34.2 | 20.4~69.4 |
| 慈溪[40, 43] | 0.36~3.04 | 0.28~1.63 | 0.57~2.37 | 16.4~28.0 | 44.6~55.4 |
| 闽江口[33] | 0.22~4.36 | 0.24~1.91 | 0.21~1.34 | 19 | 75 |
| 珠江口[44, 45] | 2.32~7.62 | 1.2~2.4 | 0.27~0.59 | 13.09~32.28 | 20.34~42.23 |
沿海滩涂转变为耕地路径是垦区地形、植被、土壤以及区位等自然条件和滩涂围垦开发主体等人文因素共同作用的复杂过程。通过对1986-2016年31幅Landsat TM和OLI遥感影像人工判读得到江苏沿海15个垦区滩涂转变为耕地的演变路径,其中2个垦区滩涂围垦后经历“盐生植被→养殖水体→耕地”的变化过程;13个垦区均经历了“盐生植被→耕地”的变化过程（表3）,与其他研究一致[3],李建国研究1977-2014年江苏中部沿海,光滩/盐生植被转变为耕地占比高达87.76%,养殖水体转变为耕地占比仅为12.24%[3]。
表3 1986-2016年滩涂围垦区耕地利用演变路径
Tab. 3 Trajectories of cropland use at the coastal reclamation zones from 1986 to 2016
| 垦区 | 年份 | 1986-2016年土地利用转移路径 | 围垦时间(年) | 耕作时间(年) |
|---|---|---|---|---|
| O | 1979s | AAAAAAAAAAAAAAAAAAAAAAAAAACCCCC | 37 | 5 |
| N | 1979 | CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC | 37 | >31 |
| M | 1981 | HCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC | 35 | 30 |
| L | 1984 | BHHHHHHCCCCCCCCCCCCCCCCCCCCCCCC | 32 | 24 |
| K | 1986 | HHHHHHHHHHHHHHHHHHCCCCCCCCCCCCC | 30 | 13 |
| J | 1989 | HHHHACCCCCCCCCCCCCCCCCCCCCCCCCC | 27 | 26 |
| I | 1990 | BBBBBBBBBAAAAAAAAAAAACCCCCCCCCC | 26 | 10 |
| H | 1997s | HHHHHHHHHHHHHHHHHHHCCCCCCCCCCCC | 19 | 12 |
| G | 1997 | HHHHHHHHHHHHHCCCCCCCCCCCCCCCCCC | 19 | 18 |
| F | 1998 | HHHHHHHHHHHHHHCCCCCCCCCCCCCCCCC | 18 | 17 |
| E | 2001 | HHHHHHHHHHHHHHHHCCCCCCCCCCCCCCC | 15 | 15 |
| D | 2005 | BBBBBBHHHHHHHHHHHHHHCCCCCCCCCCC | 11 | 11 |
| C | 2006 | BBBBBBBBBBBBBBBBHHHHHHHHHHCCCCC | 10 | 5 |
| B | 2009 | BBBHHHHHHHHHHHBBBBBBBBBHHHHCCCC | 7 | 4 |
| A | 2012 | HHHHHHHHHHHHHHHHHHHHHHHHHHHCCCC | 4 | 4 |
结合垦区调研情况,初步探析江苏中部沿海滩涂转变为耕地演变路径的内在驱动机制。通过分析得到,20世纪70年代以茅草和芦苇为主要植被的滩涂围垦区,由于土壤盐分低,由农户进行开垦直接进行农业耕作（垦区N）;临近海堤且由临港工业园开垦的耕地经历“盐生植被→养殖水体→耕地”的变化过程（垦区O）。20世纪80年代以后,随着滩涂围垦强度加大,围垦区不断向海推进,垦区滩涂类型多样,有光滩和盐生植被滩,且盐生植被密度和种类不一,该阶段滩涂围垦开发主体以农场为主,沿海滩涂转变为耕地的方式主要为“盐生植被→耕地”。20世纪90年代,由市区级沿海开发集团开发的滩涂围垦区经历“盐生植被→养殖水体→耕地”的演变过程（垦区I）;而省级沿海开发集团开的滩涂围垦区经历“盐生植被→耕地”的演变过程（垦区H、G、F）。21世纪以来,滩涂围垦后,农场开发一般直接开垦为耕地（垦区D）。沿海经济开发区在将滩涂开发为城镇之前,先将滩涂开垦为耕地（垦区B和垦区D）,提高已围滩涂利用效益。同时,对于面积相对较小的滩涂垦区,开发主体也会将其直接开发为耕地（垦区E）。因此,江苏中部沿海滩涂垦区滩涂转为耕地演变路径受到围垦初期地形、植被等自然条件作用的同时,也受到开发主体如农户、农场、经济开发区、工业区等开发主体以及开发规模等因素共同影响。江苏中部沿海滩涂“盐生植被→耕地”的演变虽然缩短了滩涂农垦的周期,但是由于土壤盐分含量高等因素,也会带来滩涂围垦后抛荒闲置现象的出现,围垦时间远大于耕作时间,围垦闲置抛荒多年后开始耕作,如垦区L、K、H、B和C。
土地利用/覆被变化能够引起与土壤相联系的生物化学过程发生改变[23],因此,滩涂围垦区滩涂转变为耕地的演变路径对于耕地质量演变具有重要影响。运用“时空代换”的方法,通过比较不同年限滩涂围垦区耕地质量空间差异,揭示滩涂围垦后耕地质量演变趋势。从滩涂围垦区初始状态和滩涂转变为耕地演变路径两个方面,本文将垦区分为四类,第Ⅰ类是植被稀少的混合滩或者光滩经过围垦直接转为耕地,如垦区A、B、C、D、G、H和L;第Ⅱ类是有潮沟分布的混合滩或者光滩经过围垦转为耕地,如垦区E和N;第Ⅲ类是植被稀少的混合滩或者光滩经过养殖水体,再转为耕地,如垦区I和O;第Ⅳ类是围垦初期植被浓密的混合滩经过围垦直接转为耕地,如垦区F、J、K和M。
4.3.1 土壤有机质演变趋势分析 沿海淤泥质滩涂具有重要的生态服务功能,比如碳汇等。随着滩涂围垦后,沿海淤泥质滩涂失去了湿地淹水条件,滩涂土壤固碳等生态服务功能逐步发生转变。围垦初期盐生植被浓密的垦区耕地土壤,土壤有机质含量较高,如垦区F、J、K和M（图2）,其中垦区J土壤有机质含量最高（1.88%）,该垦区覆盖植被为芦苇、茅草、盐蒿和互花米草混合[46]。地势低洼且有潮沟分布的垦区耕地,土壤盐分高,作物长势不好,土壤有机质含量相对较低,如垦区E和N。经过养殖水体再转为耕地的垦区耕地土壤,由于耕作时间短,土壤有机质含量偏低,如垦区I和O。围垦初期盐生植被覆盖、潮沟分布和围垦过程中开展养殖（第Ⅱ、Ⅲ和Ⅳ类型垦区）对土壤有机质含量影响较大。
图2 不同滩涂围垦区土壤有机质差异
Fig. 2 Differences of soil organic matter at different reclamation zones
第I类型垦区滩涂转变为耕地的演变路径基本一致,从第Ⅰ类型垦区（A、B、C、D、G、H和L）揭示滩涂围垦后耕地质量演变趋势。图3a显示围垦后滩涂土壤有机质含量呈现“下降→上升→波动”趋势,土壤有机质从最初的1.39%下降到0.75%,而后增加到1.37%,继而下降至1.24%。滩涂围垦后,滩涂土壤因脱离海水环境从还原状态转变为氧化状态,滩涂植被滩已累积的土壤有机碳发生矿化过程,土壤有机质围垦初期（0~7年）呈现下降趋势;围垦中期（7~19年）,人类耕作将大量作物秸秆残根输入土壤,土壤有机质含量呈现上升趋势,由于滩涂垦区耕地土壤较为敏感,受到耕作管理等因子影响较大,围垦后期（20~22年）会出现一定幅度波动。与其他研究结果一致,有学者认为围垦后20年土壤有机碳由于海洋沉积物矿化过程呈现下降趋势,而后由于农业围垦有机物输入再呈现上升趋势[16, 19]。然而也有学者研究围垦3年以上表层土壤有机碳可增加0.24%,围垦52年后,有机碳增加1.5%[20],认为土壤有机质一直处于增加趋势,其结果不同的主要原因是滩涂围垦初期土壤有机碳含量初始状态不同。
4.3.2 土壤全氮和碱解氮演变趋势分析 土壤全氮含量主要以有机氮为主,主要受到土壤有机质含量的影响。土壤全氮含量最高的垦区是盐生植被覆盖密集的垦区F、J、K和M。有潮沟分布的垦区全氮含量低,如垦区E和N。滩涂围垦后经过养殖水体的垦区I和O土壤全氮含量也很低（图4）。围垦初期盐生植被覆盖、潮沟分布和围垦过程中开展养殖（第Ⅱ、Ⅲ和Ⅳ类型垦区）对土壤全氮影响较大。从第Ⅰ类型垦区来看,随着围垦时间,土壤全氮含量呈现“下降→上升→波动”趋势,从初期的778 ug/g下降至493 ug/g,然后上升至859 μg/g,继而下降至712 μg/g（图3b）。滩涂围垦10年内,全氮含量下降并逐步上升,围垦10~19年全氮含量相对稳定,19年后存在下降趋势。土壤碱解氮,包括无机态氮和易水解的有机态氮,与土壤全氮含量密切相关。垦区F、J、K和M受到盐生植被密集覆盖影响,土壤碱解氮含量高。有潮沟分布的垦区E和N和经历养殖的垦区I和O的土壤碱解氮含量低下。围垦初期盐生植被覆盖、潮沟分布和围垦过程中养殖对土壤碱解氮影响较大。从第Ⅰ类型垦区来看,随着围垦时间,土壤碱解氮呈现“下降→上升”趋势（图3d）,从初期的57.91 mg/kg下降到26.52 mg/kg,之后上升到68.77%。滩涂围垦7年内土壤碱解氮含量下降,围垦7~32年内呈现逐步上升趋势。
4.3.3 土壤全磷和有效磷演变趋势分析 土壤全磷分为无机磷和有机磷,其中有机磷主要以高分子形态存在,有效性不高,无机磷以吸附态和钙、铁、铝等磷酸盐为主,存在形态受到pH影响很大[40]。土壤磷素的缺乏主要受到土壤母质的限制[47]。江苏中部沿海盐生植被滩分布的垦区全磷含量较高,与其他研究存在差异,有学者认为光滩沉积物中总磷的含量最高（1026 mg/kg）,其次为芦苇滩、互花米草滩、混合滩、盐蒿滩[8],主要原因在于磷素被植物吸收[48],然而江苏中部沿海滩涂沉积物砂粒和粉粒含量较高,原生磷灰石磷主要存在于粗颗粒中。潮沟分布和养殖水体对滩涂垦区全磷含量影响较小。从第Ⅰ类型垦区来看,围垦初期土壤全磷含量较小,受到人类耕作施肥影响,土壤全磷含量有所上升,围垦后土壤全磷呈现“上升”趋势（图3c）。
图3 滩涂围垦后土壤理化性质变化趋势
Fig. 3 Change trends of soil properties following reclamation duration
图4 不同滩涂围垦区土壤养分差异
Fig. 4 Differences of soil fertility at different reclamation zones
土壤有效态磷主要为水溶性磷、吸附态磷和有机态磷,由于土壤对磷具有吸附和释放作用。盐生植被密集垦区、经历养殖的垦区以及有潮沟分布的垦区土壤有效磷含量相对较高。滩涂围垦后,土壤中Ca2+的不断流失,Ca/P比不断减小,P的有效性会相对提高,同时,人类耕作加大对磷肥施入量,土壤有效磷含量逐步提高。围垦10年内,土壤有效磷变化不显著,围垦10~32年土壤有效磷呈现增加趋势（图3e）。
4.3.4 土壤阳离子交换量演变趋势分析 土壤阳离子交换量是土壤肥力重要影响因素之一,直接反映土壤保蓄、供应和缓冲阳离子养分的能力[49]。土壤阳离子交换量受到土壤质地影响较大,如垦区K（图4,图5）,受到盐生植被、养殖以及潮沟等影响较小。从第Ⅰ类型垦区来看,滩涂围垦后,土壤阳离子交换量呈现“下降→上升”趋势（图3f）。
图5 不同滩涂围垦区土壤颗粒组成
Fig. 5 Differences of soil particle sizes at different reclamation zones
4.3.5 不同围垦区土壤盐分和pH演变趋势 土壤盐分是沿海滩涂围垦区耕地土壤重要限制性指标之一[50-52],受到降雨和地形影响,土壤盐分的时空变异很高。从图6可以看出,受到降雨的影响,滩涂垦区土壤含水量高达32.93%（表1）,除了垦区J和O外,滩涂围垦区土壤盐分差异并不显著,其演变趋势（图3g）与前人研究不同[50-52]。前人研究得到随着滩涂围垦年限,土壤表层盐分不断下降,大约在30年左右达到稳定脱盐水平[50],土壤剖面盐分呈现“均匀型—表聚型—震荡型—底聚型—震荡型—均匀型”的过程[52]。围垦后,滩涂土壤在降雨和蒸发作用下,土壤盐分在剖面上下迁移,呈现季节性变化特征,1-6月处于积盐期,7-9月处于脱盐期[53]。研究土壤盐分随着滩涂围垦的变化趋势的最佳时间为秋季和冬季,降雨对分析滩涂围垦土壤盐分演变趋势影响很大。
图6 不同滩涂围垦区土壤盐分、pH和含水量差异
Fig. 6 Differences of soil water, salinity and pH at different reclamation zones
土壤pH在不同垦区之间无显著性差异（图6）。盐生植被覆盖垦区、经历“盐生植被—养殖—耕地”垦区以及有潮沟分布的垦区土壤pH值较高,主要原因在于这些垦区土壤Ca2+流失相对较慢,同时人们在养殖过程中会施入石灰调节pH值。从第Ⅰ类型垦区来看,滩涂围垦后,滩涂土壤pH值呈现下降趋势,垦区A（2012年）pH值最高。垦区pH值的变化主要受到CO32-–HCO3-–Ca2+平衡体系的影响[21, 54],滩涂围垦后Ca2+的不断流失导致pH值不断下降。
4.3.6 沿海滩涂土壤质地梯度特征分析 土壤粘粒、粉粒和砂粒在江苏沿海中部滩涂围垦区在经纬度方向上呈现显著空间差异（图7）。土壤粘粒和粉粒占比随着纬度增加,呈现增加趋势,即纬度每增加1°,土壤粘粒和粉粒占比分别增加7.69%和12.60%,土壤粘粒占比在纬度变化比土壤粉粒较为缓慢;土壤砂粒占比随着纬度增加,呈现下降趋势,即纬度每增加1°,土壤砂粒占比下降20.29%,土壤砂粒占比在纬度方向变化比土壤粉粒和粘粒较快。土壤粘粒和粉粒占比随着经度增加,呈现下降趋势,即经度每增加1°,土壤粘粒和粉粒占比分别下降20.04%和31.00%,土壤粘粒占比在经度方向上比土壤粉粒较为缓慢;土壤砂粒占比随着经度增加,呈现增加趋势,即经度每增加1°,土壤砂粒占比增加51.05%,土壤砂粒占比在经度方向上变化比土壤粉粒和粘粒较快。
图7 经纬方向上土壤颗粒组成的变化趋势
Fig. 7 Change trends of soil particle sizes along altitude and latitude
前两个典型排序轴能够解释87%的耕地质量因子的变异（表4）,第一轴主要解释有效磷、盐分、阳离子交换量、土壤含水量、粘粒、砂粒、粉粒和pH的变异;第二轴主要解释有机质、全氮、碱解氮和全磷的差异。从耕地质量因子、土壤样点以及耕地质量环境变量三序图（图8）中可以看出,耕地质量因子可分为三类,第一类为土壤砂粒、粉粒、粘粒、全磷、pH和含水量;第二类为有机质、全氮、碱解氮和阳离子交换量;第三类为有效磷和土壤电导率。从耕地质量因子与环境因子的关系来看,土壤有机质、全氮、碱解氮、CEC与耕作年限呈现正相关关系。土壤砂粒、粉粒、pH、全磷与围垦年限呈现负相关关系。土壤有效磷与围垦年限呈现正相关关系。土壤盐分与所选环境变量相关性不高。
表4 典范对应轴特征值、累计解释率和耕地质量因子得分
Tab. 4 Eigenvalue, cumulative proportion of components and the scores of cropland quality factors
| OM | TN | TP | AP | AN | CEC | EC | |
|---|---|---|---|---|---|---|---|
| CA1 | -0.10 | -0.09 | -0.06 | 0.31 | -0.13 | -0.11 | 0.57 |
| CA2 | -0.14 | -0.13 | 0.12 | 0.04 | -0.15 | -0.07 | -0.01 |
| pH | W | Clay | Silt | Sand | 累计贡献 | 特征值 | |
| CA1 | -0.15 | -0.18 | -0.11 | -0.09 | -0.19 | 0.67 | 0.04773 |
| CA2 | 0.16 | 0.14 | 0.04 | 0.14 | 0.18 | 0.87 | 0.01362 |
本文通过遥感影像目视解译、野外土壤采样采集和实验分析,揭示江苏中部沿海滩涂围垦耕地质量演变趋势,研究结果表明：
（1）江苏中部沿海滩涂土壤总体呈现盐碱度高、养分贫瘠等特征且变异程度较高。从中国海岸带分布来看,江苏中部沿海滩涂土壤有机碳含量高于辽河口和渤海湾,低于杭州湾、闽江口和珠江口,但由于滩涂沉积物以砂粒和粉砂为主,土壤全磷含量高于辽河口、渤海湾、杭州湾、闽江口以及珠江口。
（2）滨海滩涂转变为耕地路径是由垦区自然条件如围垦初期垦区地形、盐生植被状况和土壤等、开发主体（农户、农场、经济开发区和工业园区等）、开发规模等因素共同作用。江苏中部沿海滩涂围垦模式已从“盐生植被→养殖水体→耕地”转变为“盐生植被→耕地”,这种转变缩短了滩涂围垦转变为耕地资源的周期,但也会带来滩涂围垦后闲置撂荒等问题发生。
（3）滩涂围垦后,耕地质量因子演变趋势主要分为四种类型即上升型,如土壤全磷、有效磷、粘粒含量;下降型,如土壤砂粒含量;下降—上升型,如有机质、全氮、碱解氮和CEC;上升—下降型,如土壤盐分和pH。滩涂围垦初期,滩涂土壤脱离海水环境,盐生植被所固定的有机碳发生矿化过程而流失,同时,土壤盐分和pH受到蒸腾和蒸发作用呈现快速上升趋势。围垦中期,随着人类耕作向土壤中输入作物秸秆等有机物,土壤有机碳、养分等呈现上升趋势,土壤盐分和pH不断降低。围垦后期,耕地土壤因子呈现一定幅度的波动现象,由于沿海滩涂围垦区耕地土壤形成时间短,对耕作管理敏感性高。
本文在分析江苏中部沿海滩涂土壤基本理化性质的基础上,初步研究了淤涨型沿海滩涂转变为耕地路径的内在驱动机理,探索了沿海滩涂围垦后耕地质量演变趋势及其影响因素,对加强耕地后备资源潜力区——沿海滩涂围垦后耕地资源可持续利用具有一定的支撑作用。但由于耕地质量演变过程的复杂性,以及数据受限,本文在揭示自然状态的滩涂围垦耕地质量演变趋势和人工实施不同肥料下耕地质量演变趋势的共性和差异性等方面尚显不足。对此,作者在后续研究中,将选择典型垦区加强该方面的研究,不断完善和深化滨海滩涂围垦后耕地质量演变趋势及影响机理研究。
The authors have declared that no competing interests exist.
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The tidal flat resource of China. https://doi.org/10.11849/zrzyxb.1997.04.003 Magsci [本文引用: 2] 摘要
我国的海涂面积巨大,随着中国耕地资源的不断减少及人口的迅速增加,海涂资源作为后备土地资源的重要性越来越突出。在分析中国海涂资源的分布、成因、类型后,指出了泥沙供应量、潮差是影响我国海涂发育的两大重要因素,探讨了海涂开发的现状及开发利用中存在的问题,进而根据海涂资源分布的自然特点、开发利用现状、经济技术条件、开发利用前景等因素对我国的海涂进行了利用区划。
中国的海洋海涂资源 .https://doi.org/10.11849/zrzyxb.1997.04.003 Magsci [本文引用: 2] 摘要
我国的海涂面积巨大,随着中国耕地资源的不断减少及人口的迅速增加,海涂资源作为后备土地资源的重要性越来越突出。在分析中国海涂资源的分布、成因、类型后,指出了泥沙供应量、潮差是影响我国海涂发育的两大重要因素,探讨了海涂开发的现状及开发利用中存在的问题,进而根据海涂资源分布的自然特点、开发利用现状、经济技术条件、开发利用前景等因素对我国的海涂进行了利用区划。
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Historical evolution of tidal flat reclamation in the Jiangsu coastal areas. 近代以来江苏沿海滩涂围垦历史演变研究 . |
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The changes and dynamics of coastal wetlands and reclamation areas in central Jiangsu from 1977 to 2014. https://doi.org/10.11821/dlxb201501002 URL [本文引用: 4] 摘要
通过野外实地调研与遥感影像解译相结合的方式,研究1977-2014年(1977、1984、2000、2007与2014年)江苏中部滩涂湿地演化与围垦空间演变的规律。结果表明,1977-2014年江苏中部滨海湿地射阳河口以南岸线段总体以淤长为主,但是也存在侵蚀的岸线段,总体淤长/侵蚀速度在±20 m/yr左右,最高值出现在东台和如东洋口港附近。研究区湿地围垦的速度远高于岸线淤长的速度,基本维持在50 m/yr以上。1977-2014年江苏滨海湿地的生态关键区面积出现了快速的退化趋势,特别是盐生植被空间的快速萎缩,主要出现在射阳南部和大丰市。调查发现研究区传统的湿地围垦开发演变模式是光滩→盐生植被→养殖水面→耕地→建设用地。但是现在由于新技术和新方法的应用,极大地缩短了围垦演变路径和周期,有助于围垦经济效益的提高。江苏滨海湿地围垦后土地开发利用强度呈较为明显的上升趋势。同时,江苏滨海湿地开发的热点空间在区域上主要集中于几个重要的港口及其腹地建制镇附近,但总体规模不大。
1977-2014年江苏中部滨海湿地演化与围垦空间演变趋势 .https://doi.org/10.11821/dlxb201501002 URL [本文引用: 4] 摘要
通过野外实地调研与遥感影像解译相结合的方式,研究1977-2014年(1977、1984、2000、2007与2014年)江苏中部滩涂湿地演化与围垦空间演变的规律。结果表明,1977-2014年江苏中部滨海湿地射阳河口以南岸线段总体以淤长为主,但是也存在侵蚀的岸线段,总体淤长/侵蚀速度在±20 m/yr左右,最高值出现在东台和如东洋口港附近。研究区湿地围垦的速度远高于岸线淤长的速度,基本维持在50 m/yr以上。1977-2014年江苏滨海湿地的生态关键区面积出现了快速的退化趋势,特别是盐生植被空间的快速萎缩,主要出现在射阳南部和大丰市。调查发现研究区传统的湿地围垦开发演变模式是光滩→盐生植被→养殖水面→耕地→建设用地。但是现在由于新技术和新方法的应用,极大地缩短了围垦演变路径和周期,有助于围垦经济效益的提高。江苏滨海湿地围垦后土地开发利用强度呈较为明显的上升趋势。同时,江苏滨海湿地开发的热点空间在区域上主要集中于几个重要的港口及其腹地建制镇附近,但总体规模不大。
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The mechanism and trend of coastal erosion of Jiangsu Province in China. https://doi.org/10.3321/j.issn:1000-0585.2002.04.009 URL [本文引用: 2] 摘要
江苏省侵蚀海岸的总长度为 30 1 7km ,分为 4段 :废黄河三角洲海岸、港海岸、吕四海岸以及海州湾的沙质海岸。各段海岸侵蚀原因不同。废黄河三角洲海岸是因黄河改道失去泥沙来源 ;吕四与港海岸则因辐射沙洲调整过程中滨岸水道的向岸移动造成的 ;而北部沙岸则是因人类活动 (上游建设水库及开挖海滩沙 )的干扰。江苏海岸是一个沉积物准封闭系统 ,全球性海平面上升将加剧这一侵蚀过程 ,预计未来侵蚀海岸的长度将增加 ,辐射沙洲区的外围沙洲将因侵蚀而向中心区退缩。一些目前是隐型侵蚀的岸段将向显性侵蚀的阶段发展。由于连云港到长江口北支的岸段是软性海岸 ,缺乏硬质节点 ,在没有建造大型人工设施的前提下 ,估计江苏海岸动态及制定开发规划时必须考虑平直化的大趋势。
江苏海岸侵蚀过程及其趋势 .https://doi.org/10.3321/j.issn:1000-0585.2002.04.009 URL [本文引用: 2] 摘要
江苏省侵蚀海岸的总长度为 30 1 7km ,分为 4段 :废黄河三角洲海岸、港海岸、吕四海岸以及海州湾的沙质海岸。各段海岸侵蚀原因不同。废黄河三角洲海岸是因黄河改道失去泥沙来源 ;吕四与港海岸则因辐射沙洲调整过程中滨岸水道的向岸移动造成的 ;而北部沙岸则是因人类活动 (上游建设水库及开挖海滩沙 )的干扰。江苏海岸是一个沉积物准封闭系统 ,全球性海平面上升将加剧这一侵蚀过程 ,预计未来侵蚀海岸的长度将增加 ,辐射沙洲区的外围沙洲将因侵蚀而向中心区退缩。一些目前是隐型侵蚀的岸段将向显性侵蚀的阶段发展。由于连云港到长江口北支的岸段是软性海岸 ,缺乏硬质节点 ,在没有建造大型人工设施的前提下 ,估计江苏海岸动态及制定开发规划时必须考虑平直化的大趋势。
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The effect of reclamation on mud flat development in Chongming Island, Shanghai. https://doi.org/10.3969/j.issn.1000-6850.2006.08.117 URL Magsci [本文引用: 1] 摘要
由于长江口泥沙的淤积，使上海崇明东滩成为一个不断淤涨的土地资源。近50年来，崇明岛共进行了多次大规模的围垦。此项研究以近20年来的Landsat TM和ETM遥感卫星数据为主要数据源，并结合实地景观调查，对不同时期的人类围垦面积和滩涂发育面积之间的关系进行探讨。结果显示，滩涂湿地的面积在逐年变小：从1987年的19705.09 hm2 锐减到2002年的4773.08hm2，减少了75.78%；并且滩涂湿地面积的年减少率为995.47 hm2/a，比年围垦率的729.08hm2/a增加了36.54%。过度围垦后，滩面宽度变窄，自然植被破坏，影响自然促淤，淤涨速率明显减慢。随着滩涂围垦的加剧、未来海平面的上升和河流泥沙大量减少，将会导致潮滩植被进一步破坏。随着崇明东滩每年向外延伸，滩涂湿地也将会发生演替。因此，充分运用“3S技术”，探讨湿地发育和形成的机理，指导科学围垦和土地利用规划，是非常迫切也非常实用的方法。同时，还可以通过动态保护管理，进一步对围垦在经济、生态和环境上的得失作出正确的评价。
人类围垦活动对上海崇明东滩滩涂发育的影响 .https://doi.org/10.3969/j.issn.1000-6850.2006.08.117 URL Magsci [本文引用: 1] 摘要
由于长江口泥沙的淤积，使上海崇明东滩成为一个不断淤涨的土地资源。近50年来，崇明岛共进行了多次大规模的围垦。此项研究以近20年来的Landsat TM和ETM遥感卫星数据为主要数据源，并结合实地景观调查，对不同时期的人类围垦面积和滩涂发育面积之间的关系进行探讨。结果显示，滩涂湿地的面积在逐年变小：从1987年的19705.09 hm2 锐减到2002年的4773.08hm2，减少了75.78%；并且滩涂湿地面积的年减少率为995.47 hm2/a，比年围垦率的729.08hm2/a增加了36.54%。过度围垦后，滩面宽度变窄，自然植被破坏，影响自然促淤，淤涨速率明显减慢。随着滩涂围垦的加剧、未来海平面的上升和河流泥沙大量减少，将会导致潮滩植被进一步破坏。随着崇明东滩每年向外延伸，滩涂湿地也将会发生演替。因此，充分运用“3S技术”，探讨湿地发育和形成的机理，指导科学围垦和土地利用规划，是非常迫切也非常实用的方法。同时，还可以通过动态保护管理，进一步对围垦在经济、生态和环境上的得失作出正确的评价。
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The ecological response of typical mud flat to sea level change in Jiangsu coastal plain. 江苏滨海潮滩湿地对潮位变化的生态响应 . |
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Characteristics of tidal flat sediment at different ecologic zones, north Jiangsu Province.
苏北潮滩不同生态带沉积物分布特征 .
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Distribution characteristics of organic carbon, nitrogen, and phosphorous in sediments from different ecologic zones of tidal flats in north Jiangsu Province. https://doi.org/10.3321/j.issn:1001-7410.2007.05.017 URL Magsci [本文引用: 1] 摘要
通过对比苏北潮滩湿地不同生态带的表层以及柱状沉积物中总有机碳、总氮、总磷和有机磷含量,并结合不同植被不同植株部位中碳、氮、磷的含量变化,分析了潮滩沉积物中碳、氮、磷的垂向和水平分布特征与规律,探讨了不同生态带以及潮滩植被对碳、氮、磷等生源要素的富集作用。对比分析结果表明:苏北潮滩湿地各生态带对不同的测量指标有着不同的富集作用,互花米草滩的总有机碳、总氮和有机磷含量要远大于其他几个生态带,光滩沉积物中总磷的含量最高; 粒度效应是控制互花米草前缘地带以及互花米草滩沉积物中有机碳和氮分布的一个重要因素,盐蒿和芦苇滩中有机碳和氮的分布更多的是受粒度之外的其他因素影响; 不同生态带表层沉积物中的C/N比值分布,大致可反映其有机物来源的差异,而不同生态带中柱状沉积物中的C/N比值相对接近,很难根据C/N比值大小来对不同生态带中的有机物来源进行判断,这可能是埋藏在柱状沉积物中的有机物更多的受到了早期成岩作用造成的。植被对潮滩湿地中碳、氮、磷的分布有着重要影响,3种物质在互花米草、盐蒿和芦苇中的含量差别不是很大,因此潮滩植被对沉积物中上述3种物质的贡献差别主要是由不同植被的生物量和其所处环境的沉积动力差异造成的。
苏北潮滩湿地不同生态带碳、氮、磷分布特征 .https://doi.org/10.3321/j.issn:1001-7410.2007.05.017 URL Magsci [本文引用: 1] 摘要
通过对比苏北潮滩湿地不同生态带的表层以及柱状沉积物中总有机碳、总氮、总磷和有机磷含量,并结合不同植被不同植株部位中碳、氮、磷的含量变化,分析了潮滩沉积物中碳、氮、磷的垂向和水平分布特征与规律,探讨了不同生态带以及潮滩植被对碳、氮、磷等生源要素的富集作用。对比分析结果表明:苏北潮滩湿地各生态带对不同的测量指标有着不同的富集作用,互花米草滩的总有机碳、总氮和有机磷含量要远大于其他几个生态带,光滩沉积物中总磷的含量最高; 粒度效应是控制互花米草前缘地带以及互花米草滩沉积物中有机碳和氮分布的一个重要因素,盐蒿和芦苇滩中有机碳和氮的分布更多的是受粒度之外的其他因素影响; 不同生态带表层沉积物中的C/N比值分布,大致可反映其有机物来源的差异,而不同生态带中柱状沉积物中的C/N比值相对接近,很难根据C/N比值大小来对不同生态带中的有机物来源进行判断,这可能是埋藏在柱状沉积物中的有机物更多的受到了早期成岩作用造成的。植被对潮滩湿地中碳、氮、磷的分布有着重要影响,3种物质在互花米草、盐蒿和芦苇中的含量差别不是很大,因此潮滩植被对沉积物中上述3种物质的贡献差别主要是由不同植被的生物量和其所处环境的沉积动力差异造成的。
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Characteristic of halophyte and associated soil along aggradational muddy coasts in Jiangsu Province. https://doi.org/10.3321/j.issn:1000-0933.2005.01.001 URL [本文引用: 1] 摘要
江苏沿海中部在辐射沙洲的屏蔽下,成为典型的淤长性岸段。滩涂土壤具有特殊的肥力特征。本文通过对东台市笆斗垦区这一典型淤长性海岸外侧潮滩断面的地形测量和盐土植被群落调查,结合历年TM遥感卫星影像图片,选择了5个地点,分别代表海堤内茅草滩、海堤外茅草滩、原生盐蒿滩、由互花米草演替而来的盐蒿滩及互花米草滩,并对各代表点进行群落样方调查和土壤采样,对土壤样品进行有机质含量、总氮含量等肥力特征的分析。结果表明:a.1号点的有机质和全氮最高,分别为1.632%和0.067%,3号点的全磷最高,为0.151%,而5号点的全钾和全盐最高,分别为1.724%和1.823%。b.1号点的有机质和全氮在表层非常高,到第二层急剧下降,再往下变化也较小,其变化幅度明显高于其他点。c.各点土壤的平均粒径从1号点向5号点逐渐变粗。最后,本文对这些土壤肥力特征和盐生植被的关系进行了分析和讨论,指出凡受互花米草影响的土壤,其垂直变化梯度较小,而其它盐土植被类型土壤的垂直变化梯度较大。
江苏典型淤长岸段潮滩盐生植被及其土壤肥力特征 .https://doi.org/10.3321/j.issn:1000-0933.2005.01.001 URL [本文引用: 1] 摘要
江苏沿海中部在辐射沙洲的屏蔽下,成为典型的淤长性岸段。滩涂土壤具有特殊的肥力特征。本文通过对东台市笆斗垦区这一典型淤长性海岸外侧潮滩断面的地形测量和盐土植被群落调查,结合历年TM遥感卫星影像图片,选择了5个地点,分别代表海堤内茅草滩、海堤外茅草滩、原生盐蒿滩、由互花米草演替而来的盐蒿滩及互花米草滩,并对各代表点进行群落样方调查和土壤采样,对土壤样品进行有机质含量、总氮含量等肥力特征的分析。结果表明:a.1号点的有机质和全氮最高,分别为1.632%和0.067%,3号点的全磷最高,为0.151%,而5号点的全钾和全盐最高,分别为1.724%和1.823%。b.1号点的有机质和全氮在表层非常高,到第二层急剧下降,再往下变化也较小,其变化幅度明显高于其他点。c.各点土壤的平均粒径从1号点向5号点逐渐变粗。最后,本文对这些土壤肥力特征和盐生植被的关系进行了分析和讨论,指出凡受互花米草影响的土壤,其垂直变化梯度较小,而其它盐土植被类型土壤的垂直变化梯度较大。
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Land use change and farmer behavior in reclaimed land in the middle Jiangsu coast, China. https://doi.org/10.1016/j.ocecoaman.2016.12.015 URL [本文引用: 1] 摘要
In order to find space for urban expansion and food production, China is rapidly converting its coastal wetlands through large-scale land reclamation. These conversions are dramatically altering the coastal environment, affecting the associated ecosystem services and threatening the regional ecological security. Since this trend is expected to continue for maintaining the economic growth and food security considerations, understanding the extent of reclamation and its related land use changes is important for sustainable coastal land use planning and management. In this study, we analyze land use changes between 1977 and 2015 in middle Jiangsu coast, China, an area that is characterized by land reclamation from wetland conversion. In addition, we surveyed local farmers occupying the reclaimed land and compared their farm characteristics and attitudes against their inland counterparts to understand their role in these processes. We observed that 17% of the reclaimed land was converted to farmland and 43% to aquaculture ponds during the study period. At the same time, the natural wetlands, which originally dominated the area, were substantially reduced by 96%. Characteristics of farmers cultivating the reclaimed land were relatively similar to the inland farmer in many aspects. However, coastal farmers owned larger farms with less fragmented parcels, have a higher income from their farm and showed more enthusiasms for implementing agricultural land use changes comparing to their inland counterparts. The environmental value of the coastal wetlands and the limited opportunities for further land reclamation will pose significant challenges in the context of the region being a hotspot of urban expansion and an important contributor to food production.
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Ecological security and ecosystem services in response to land use change in the coastal area of Jiangsu, China. https://doi.org/10.3390/su8080816 URL 摘要
Urbanization, and the resulting land use/cover change, is a primary cause of the degradation of coastal wetland ecosystems. Reclamation projects are seen as a way to strike a balance between socioeconomic development and maintenance of coastal ecosystems. Our aim was to understand the ecological changes to Jiangsu coastal wetland resulting from land use change since 1977 by using remote sensing and spatial analyses. The results indicate that: (1) The area of artificial land use expanded while natural land use was reduced, which emphasized an increase in production-orientated land uses at the expense of ecologically important wetlands; (2) It took 34 years for landscape ecological security and 39 years for ecosystem services to regain equilibrium. The coastal reclamation area would recover ecological equilibrium only after a minimum of 30 years; (3) The total ecosystem service value decreased significantly from $2.98 billion per year to $2.31 billion per year from 1977 to 2014. Food production was the only one ecosystem service function that consistently increased, mainly because of government policy; (4) The relationship between landscape ecological security and ecosystem services is complicated, mainly because of the scale effect of landscape ecology. Spatial analysis of changing gravity centers showed that landscape ecological security and ecosystem service quality became better in the north than the south over the study period.
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Spatial-temporal variation and driving forces of landscape patterns in the coastal zone of Yangcheng, Jiangsu.
苏北盐城海岸带景观格局时空变化及驱动力分析 .
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The variation of land use pattern in tidal flat reclamation zones in Jiangsu coastal area: A case study of Rudong County of Jiangsu Province.
江苏海岸带滩涂围垦区土地利用类型变化研究: 以江苏省如东县为例 .
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Spatial-temporal dynamics of land use and land cover change in the coastal zone of Jiangsu Province.
<p>海岸带是陆海生态系统交错带，具有重要的经济与生态价值，其生态环境具有脆弱性特征。海岸带的开发利用使其地区生态环境发生变化，而土地利用/覆被变化是地区生态环境变化的重要组成部分和主要原因之一。取1980、2000、2005、2008年4个时相的TM遥感影像为数据源，通过土地利用结构、土地利用多样性以及土地利用程度指数分析江苏省1980年以来海岸带土地利用/覆被变化的时空动态特征，揭示地域差异与梯度分异特征。研究结果表明：（1）江苏省海岸带土地利用结构表现为生态用地占比高，城镇与农村居民点占比低的特征。1980年以来，不同土地利用类型数量不断变化而结构相对稳定；类型趋于多样化且利用强度增加。（2）江苏省海岸带土地利用存在地域差异特征。土地利用结构存在不同模式且变化相对稳定；土地利用程度在南北方向上存在高低高分布特征，但逐步被打破。（3）江苏省海岸带土地利用在陆海方向上存在梯度特征。土地利用多样性陆海方向呈现低高低模式，土地利用强度陆海方向呈现高中低模式。土地利用多样性高值区逐步向海岸带中部移动；海岸带各缓冲区土地利用程度分异逐步增大。以射阳河口作为分界点，南北地区梯度规律存在差异性</p>
近年来江苏省海岸带土地利用/覆被变化时空动态研究 .
<p>海岸带是陆海生态系统交错带，具有重要的经济与生态价值，其生态环境具有脆弱性特征。海岸带的开发利用使其地区生态环境发生变化，而土地利用/覆被变化是地区生态环境变化的重要组成部分和主要原因之一。取1980、2000、2005、2008年4个时相的TM遥感影像为数据源，通过土地利用结构、土地利用多样性以及土地利用程度指数分析江苏省1980年以来海岸带土地利用/覆被变化的时空动态特征，揭示地域差异与梯度分异特征。研究结果表明：（1）江苏省海岸带土地利用结构表现为生态用地占比高，城镇与农村居民点占比低的特征。1980年以来，不同土地利用类型数量不断变化而结构相对稳定；类型趋于多样化且利用强度增加。（2）江苏省海岸带土地利用存在地域差异特征。土地利用结构存在不同模式且变化相对稳定；土地利用程度在南北方向上存在高低高分布特征，但逐步被打破。（3）江苏省海岸带土地利用在陆海方向上存在梯度特征。土地利用多样性陆海方向呈现低高低模式，土地利用强度陆海方向呈现高中低模式。土地利用多样性高值区逐步向海岸带中部移动；海岸带各缓冲区土地利用程度分异逐步增大。以射阳河口作为分界点，南北地区梯度规律存在差异性</p>
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Properties and development of soils on reclaimed alluvial sediments of the Humber estuary, eastern England. https://doi.org/10.1016/S0341-8162(02)00179-0 URL [本文引用: 1] 摘要
Sunk Island, an area of reclaimed estuarine alluvial sediments in the lower Humber estuary, provides a series of recent surfaces ranging from around 100 to 260 years old, upon which soil properties associated with soil ripening can be examined free from the disturbance of subsequent flooding and sedimentation. Within the first 100 years of pedogenesis, overall bulk density of the sediment has increased, and profile differentiation has resulted from structural development, organic matter accumulation and tillage. The original sedimentary structures of the soil have gradually become obscured and overprinted by ped and pore patterns related to wetting and drying, burrowing and root development. Aeration has accelerated organic matter decay and accentuated the difference between topsoil and subsoil contents. Variations in aeration and moisture content have resulted in mottling, which has become less prevalent as the soils develop. Properties such as available water content, organic C and cation exchange capacity (CEC) depend upon the grain size characteristics, in particular clay content. Exchangeable bases have been progressively removed, reaching a state of quasi-equilibrium within 150 years of reclamation. Crystallisation of goethite has extended progressively deeper into the profile through time, accompanied by a decrease in amorphous iron compounds.
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Chemical soil properties of reclaimed marsh soil from Zhejiang Province PR China. https://doi.org/10.1016/j.geoderma.2007.08.001 URL [本文引用: 3] 摘要
Initial pedogenesis of reclaimed saline marsh soils was studied along a chronosequence of reclaimed land at Hangzhou Bay, Zhejiang Province, P.R. China. The objective was to compare soil development of these soils with processes known for natural saline marsh soil development and to evaluate the presented form of artificial land recovery against the background of increasing population densities in China. Electrical conductivity (water) and exchangeable sodium percentage decreased rapidly after reclamation started. The decrease in pH and carbonate content suggest an incipient decalcification. Soil organic carbon decreased in the first 30cm within 20years, caused by mineralization of the organic sea sediments. After this process an accumulation of soil organic carbon due to organic matter input as a result of farming was observed. At all sites total contents of calcium, magnesium and potassium were classified as elevated to high and decreased slightly within 31years after reclamation and commencement of agricultural use. Only total phosphorus increased after construction of embankments, attributed to the application of fertilizer phosphorus. Available nutrient contents developed differently but none showed significant trends. Calcium slightly decreased as an effect of reclamation. Processes of pedogenesis were comparable to those known for natural marshes, but had an initial character. The reclamation of land in the presented manner is considered important to support high and growing population densities in China. However, agricultural management and fertilizer application has to be carefully evaluated.
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Saltmarsh soil evolution after land reclamation in Atlantic estuaries (Bay of Biscay, North coast of Spain). https://doi.org/10.1016/j.geomorph.2009.08.014 URL 摘要
Tidal wetland soils exhibit particular physical hemical properties governed mainly by tidal dynamics. On the Atlantic seaboard of the Iberian Peninsula a great swath of tidal wetlands, which correspond to semi-confined estuaries, represents land reclaimed from the 18th century to the first half of the 20th century and used for urban development or agricultural production. These interventions led to the end of tidal flooding in extensive areas of salt marshes, causing a drop in the water table that triggered pyrite oxidization processes, leaching of cations and salts and soil acidification. In many cases, these transformations have given rise to environmental problems such as the development of acid sulphate soils, a resulting decrease in pH, and the leaching of carbonates. The organic carbon storage capacity has also been altered, and the release of metal cations from sediments has caused toxic waters to appear. In order to investigate the alterations caused by the historic reclamation of estuarine soils on the north coast of Spain, natural and reclaimed lands were mapped in two estuaries (Villaviciosa and San Vicente de la Barquera) and zoned in accordance with flood frequency. The different evolutionary paths of the two studied estuarine sites after reclamation can be assessed through the description and analysis of their soils despite reclamation, some parts (i.e. lower areas) of the reclaimed lands do not remain fully isolated from tidal dynamics, whose influence varies throughout the soil profiles that have developed since. The strength of the morphological (e.g. genetic horizons), chemical (pH, metal cation concentration) and functional (balance of the carbon budget) changes suffered by the original soils seem to depend strongly on the remaining tidal influence as well as the land use of the area.
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| [18] |
Effect of reclamation time and land use on soil properties in Changjiang River Estuary, China. https://doi.org/10.1007/s11769-011-0482-0 URL [本文引用: 1] |
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Long-term changes in topsoil chemical properties under centuries of cultivation after reclamation of coastal wetlands in the Yangtze Estuary, China. https://doi.org/10.1016/j.still.2012.03.009 URL [本文引用: 3] 摘要
Dynamics of reclaimed coastal wetland soils under cultivation has not been well understood, especially at temporal scales longer than a century. In this study, we analyzed major chemical properties of plow-layer soils extensively sampled under two cropping systems (paddy rice vs. upland cropping) along a 500-year soil chronosequence created by intermittent reclamation of coastal salt marshes. The results suggested a rapid desalinization of soil immediately after reclamation. During 500 years of cultivation, the decalcification process lowered soil pH from >8 to nearly neutral. Soil organic carbon (SOC) contents markedly declined in the initial 16 years, but then rapidly recovered within 30 years and thereafter slowly accumulated with cultivation duration. Meanwhile, the recalcitrance of SOC increased. Soil nutrient status was enhanced after centuries of cultivation as indicated by the improved total nitrogen (TN) and phosphorous (TP). Amorphous Fe oxyhydrates progressively decreased, but the crystallinity of Fe oxyhydrates increased with cultivation time. Cropping system greatly affected plow-layer soil properties, with paddy soils having higher SOC, MBC, NH 4 OAc-extractable Ca 2+ , but lower TP, NH 4 OAc-extractable K + , potentially mineralizable nitrogen and Fe crystallinity than upland soils. Most soil properties revealed clear temporal patterns with more remarkable changes occurring in the first several decades after reclamation than in the following centuries. In conclusion, there was a transition phase of the soil system within the first several decades after reclamation of coastal wetlands, possibly harmful to agricultural production, but centuries of cultivation seemed to have significantly improved overall soil fertility.
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Transactions of the Chinese Scienty of Agricultural Engineering ,https://doi.org/10.3969/j.issn.1002-6819.2013.05.012 URL Magsci [本文引用: 2] 摘要
中国具有治理和修复潜力的滨海滩涂盐土面积约为2?000?hm2。滨海滩涂盐土作为新成土壤，土体发育不明显、理化性状差、肥力水平低下。该文通过对东台境内表层土壤有机碳的采样分析，在ArcGIS地理信息系统及SPSS16.0系统平台上，利用地统计分析模块中的克里格法分析东台市表层土壤有机碳的空间变异规律，并分析不同滩涂围垦年限下表层土壤有机碳、总氮、pH值、EC1:5的变化特征及其相关关系，结果显示滨海表层土壤有机碳含量与总氮、围垦年限呈极显著正相关，相关系数r分别为0.959和0.749，与pH值、电导率EC1:5呈极显著负相关，相关系数r分别为-0.478和-0.649。围垦3?a以上表层土壤有机碳可增加0.24%左右，总氮质量分数增加0.02%左右；围垦时间大于52?a，有机碳质量分数自0.1%增加到1.6%，全氮质量分数自0.03%增加到0.12%，养分等级也相应从6级增加到3级。该文研究表明，滨海盐土随着围垦年限的增长，土壤碳储量与总氮含量随之增加、pH值与EC1:5随之降低，耕地质量也相应提高。
滩涂土壤有机碳空间分布与围垦年限相关性分析 .https://doi.org/10.3969/j.issn.1002-6819.2013.05.012 URL Magsci [本文引用: 2] 摘要
中国具有治理和修复潜力的滨海滩涂盐土面积约为2?000?hm2。滨海滩涂盐土作为新成土壤，土体发育不明显、理化性状差、肥力水平低下。该文通过对东台境内表层土壤有机碳的采样分析，在ArcGIS地理信息系统及SPSS16.0系统平台上，利用地统计分析模块中的克里格法分析东台市表层土壤有机碳的空间变异规律，并分析不同滩涂围垦年限下表层土壤有机碳、总氮、pH值、EC1:5的变化特征及其相关关系，结果显示滨海表层土壤有机碳含量与总氮、围垦年限呈极显著正相关，相关系数r分别为0.959和0.749，与pH值、电导率EC1:5呈极显著负相关，相关系数r分别为-0.478和-0.649。围垦3?a以上表层土壤有机碳可增加0.24%左右，总氮质量分数增加0.02%左右；围垦时间大于52?a，有机碳质量分数自0.1%增加到1.6%，全氮质量分数自0.03%增加到0.12%，养分等级也相应从6级增加到3级。该文研究表明，滨海盐土随着围垦年限的增长，土壤碳储量与总氮含量随之增加、pH值与EC1:5随之降低，耕地质量也相应提高。
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Effects of long-time cultivation on physicochemical properties of coastal saline soil and wheat production at reclamation areas of Jiangsu Province. https://doi.org/10.5846/stxb201502060296 URL [本文引用: 1] 摘要
江苏沿海地区拥有丰富的滩涂资源,滩涂围垦长期以来为国家提供了大量土地利用后备资源,而耕地又是其围垦后最主要的土地利用方式之一.利用实验室土壤理化分析调查江苏东台滩涂围垦区耕种60a内耕地土壤理化属性及对应小麦产量的变化.结果表明:(1)在58a的耕种过程中,耕地土壤整体表现出脱盐、脱碱和养分积累的的趋势,土壤电导率(EC1∶5)、PH1∶2.5由耕种前的5.29dS/m和8.76下降至0.11dS/m和7.93,土壤有机质(SOM)和全氮(TN)则由2.64g/kg和0.15g/kg上升至13.72g/kg和1.12g/kg;(2)土壤碱解氮(AH-N)、有效磷(AP)和速效钾(AK)受施肥和作物生长影响强烈,除AK持续流失外,AH-N和AP均表现出先增长后减少的趋势;(3)土壤碳氮比(C/N)和阳离子交换量(CEC)在耕种15-53a经历了剧烈波动,反应出此期间该地区土壤的脆弱性,除AK外,各土壤理化指标均在耕种53a后开始影响20cm以下的深层土壤;(4)随着土壤环境的改善,小麦产量的上升经历了快速增产(0-15a)、波动中产(15-53a)和稳定高产(53a以上)3个阶段,在耕种53年后可达到该品种小麦(扬麦16)正常产量.虽然高强度的农业开发使土壤质量和小麦产量的都有了大幅提升,但耕种0-40年间所表现出的土壤环境的剧烈变化和波动,以及化肥投入与小麦产量之间不对应所可能导致的生态系统问题却应当引起重视,为日后的农业开发提供参考依据.
长期耕种对江苏沿海围垦区滨海盐土理化性质和小麦产量的影响 .https://doi.org/10.5846/stxb201502060296 URL [本文引用: 1] 摘要
江苏沿海地区拥有丰富的滩涂资源,滩涂围垦长期以来为国家提供了大量土地利用后备资源,而耕地又是其围垦后最主要的土地利用方式之一.利用实验室土壤理化分析调查江苏东台滩涂围垦区耕种60a内耕地土壤理化属性及对应小麦产量的变化.结果表明:(1)在58a的耕种过程中,耕地土壤整体表现出脱盐、脱碱和养分积累的的趋势,土壤电导率(EC1∶5)、PH1∶2.5由耕种前的5.29dS/m和8.76下降至0.11dS/m和7.93,土壤有机质(SOM)和全氮(TN)则由2.64g/kg和0.15g/kg上升至13.72g/kg和1.12g/kg;(2)土壤碱解氮(AH-N)、有效磷(AP)和速效钾(AK)受施肥和作物生长影响强烈,除AK持续流失外,AH-N和AP均表现出先增长后减少的趋势;(3)土壤碳氮比(C/N)和阳离子交换量(CEC)在耕种15-53a经历了剧烈波动,反应出此期间该地区土壤的脆弱性,除AK外,各土壤理化指标均在耕种53a后开始影响20cm以下的深层土壤;(4)随着土壤环境的改善,小麦产量的上升经历了快速增产(0-15a)、波动中产(15-53a)和稳定高产(53a以上)3个阶段,在耕种53年后可达到该品种小麦(扬麦16)正常产量.虽然高强度的农业开发使土壤质量和小麦产量的都有了大幅提升,但耕种0-40年间所表现出的土壤环境的剧烈变化和波动,以及化肥投入与小麦产量之间不对应所可能导致的生态系统问题却应当引起重视,为日后的农业开发提供参考依据.
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Effects of distribution intensity on spatio-temporal differentiation of soil partical size in recalamtion areas of tidal flat. 不同干扰强度对滩涂围垦区土壤颗粒组成的时空分异特征的影响 . |
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The influence of land use change on soil quality of soil genetic layers: a case study on the coastal plain of south Hangzhou bay. https://doi.org/10.3321/j.issn:0375-5444.2006.04.005 URL [本文引用: 2] 摘要
以杭州湾南岸滨海平原为研究区，通过定点配对土壤采样分析，选取有机质、全氮、全磷、速效磷、速效钾、全盐、pH值等要素作为土壤质量评价指标．分析了1982-2003年土地利用变化对土壤发生层质量演化的影响。结果表明：①1982-2003年杭州湾南岸滨海平原土壤发生层质量的总体演化特征表现为A层综合质量指数明显下降，B（或P）、C（或W）层略有上升。整个土壤发生层全磷含量普遍下降．其他单质量指标的变化差异较大。②土地利用方式变化使得不同发生层的土壤有机质含量等单质量指标和综合质量指数的变化都明显大于土地利用方式未发生变化的土壤，其变化量表现为A层〉B（或P）层〉C（或W）层。③土地利用变化引起的土壤耕种、栽培、施肥和排灌制度的变化，改变着土壤成土过程．从而对土壤发生层质量演化产生直接影响．
土地利用变化对土壤发生层质量演化的影响: 以杭州湾南岸滨海平原为例 .https://doi.org/10.3321/j.issn:0375-5444.2006.04.005 URL [本文引用: 2] 摘要
以杭州湾南岸滨海平原为研究区，通过定点配对土壤采样分析，选取有机质、全氮、全磷、速效磷、速效钾、全盐、pH值等要素作为土壤质量评价指标．分析了1982-2003年土地利用变化对土壤发生层质量演化的影响。结果表明：①1982-2003年杭州湾南岸滨海平原土壤发生层质量的总体演化特征表现为A层综合质量指数明显下降，B（或P）、C（或W）层略有上升。整个土壤发生层全磷含量普遍下降．其他单质量指标的变化差异较大。②土地利用方式变化使得不同发生层的土壤有机质含量等单质量指标和综合质量指数的变化都明显大于土地利用方式未发生变化的土壤，其变化量表现为A层〉B（或P）层〉C（或W）层。③土地利用变化引起的土壤耕种、栽培、施肥和排灌制度的变化，改变着土壤成土过程．从而对土壤发生层质量演化产生直接影响．
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Soil quality evolution in coastal reclamtion zones: A case study of Rudong County of Jiangsu Province. https://doi.org/10.3724/SP.J.1011.2011.00415 URL Magsci [本文引用: 1] 摘要
<p>对江苏省如东县不同年限的滩涂围垦区和光滩土壤样品进行分析,运用SPSS软件对垦区间土壤指标进行单因素方差分析和差异显著性检验,采用土壤质量综合指数法进行土壤质量评价,引入土壤质量障碍因子诊断模型分析关键改良因子.结果表明:滩涂围垦60 a 来,研究区土壤质量随围垦时间变化轨迹为"急剧提高—相对稳定—持续提高".围垦前10 a 土壤质量急剧提高,土壤质量指数(<em>SQI</em>)由0.19 增至0.37,年均增长11.84%,垦区差异显著;围垦10~30 a<em>SQI</em> 由0.37 增至0.42,年均增长0.54%,围垦30~40 a<em>SQI</em> 由0.42 增至0.45,年均增长0.71%,垦区差异不明显,因此围垦30 a 左右土壤质量处于相对稳定状态;围垦40~60 a 土壤质量持续提升,<em>SQI</em>由0.45 增至0.56,年均增长1.22%,垦区差异显著.土壤质量的障碍因子分析显示较低的TOC、TN和粒含量是土壤质量的主要限制因子,且与pH、盐分显著负相关,因此盐碱度降低是研究区土壤质量提升的根本原因,肥力提高以及土壤质地的改善是土壤质量进一步提升的关键.</p>
沿海滩涂围垦区土壤质量演变研究: 以江苏省如东县为例 .https://doi.org/10.3724/SP.J.1011.2011.00415 URL Magsci [本文引用: 1] 摘要
<p>对江苏省如东县不同年限的滩涂围垦区和光滩土壤样品进行分析,运用SPSS软件对垦区间土壤指标进行单因素方差分析和差异显著性检验,采用土壤质量综合指数法进行土壤质量评价,引入土壤质量障碍因子诊断模型分析关键改良因子.结果表明:滩涂围垦60 a 来,研究区土壤质量随围垦时间变化轨迹为"急剧提高—相对稳定—持续提高".围垦前10 a 土壤质量急剧提高,土壤质量指数(<em>SQI</em>)由0.19 增至0.37,年均增长11.84%,垦区差异显著;围垦10~30 a<em>SQI</em> 由0.37 增至0.42,年均增长0.54%,围垦30~40 a<em>SQI</em> 由0.42 增至0.45,年均增长0.71%,垦区差异不明显,因此围垦30 a 左右土壤质量处于相对稳定状态;围垦40~60 a 土壤质量持续提升,<em>SQI</em>由0.45 增至0.56,年均增长1.22%,垦区差异显著.土壤质量的障碍因子分析显示较低的TOC、TN和粒含量是土壤质量的主要限制因子,且与pH、盐分显著负相关,因此盐碱度降低是研究区土壤质量提升的根本原因,肥力提高以及土壤质地的改善是土壤质量进一步提升的关键.</p>
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| [25] |
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| [26] |
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| [27] |
The status and its influence of reclamation on Jiangsu coast.
江苏沿海滩涂土地资源丰富,围垦活动较为频繁,了解围垦状况及其对环境的影响具有重要的现实意义。通过对江苏沿海围垦资料的统计,分析了建国后江苏沿海滩涂围垦的特点、目的和差异,并将之分为4个阶段;讨论了江苏沿海滩涂围垦的地区分布是以盐城为中心的不平衡状况,分析了围垦对江苏沿海自然环境及经济发展的影响;预测了江苏沿海滩涂围垦的发展方向,提出条子泥等地区是江苏沿海滩涂未来围垦的潜力地区。
江苏沿海滩涂围垦现状及其对环境的影响 .
江苏沿海滩涂土地资源丰富,围垦活动较为频繁,了解围垦状况及其对环境的影响具有重要的现实意义。通过对江苏沿海围垦资料的统计,分析了建国后江苏沿海滩涂围垦的特点、目的和差异,并将之分为4个阶段;讨论了江苏沿海滩涂围垦的地区分布是以盐城为中心的不平衡状况,分析了围垦对江苏沿海自然环境及经济发展的影响;预测了江苏沿海滩涂围垦的发展方向,提出条子泥等地区是江苏沿海滩涂未来围垦的潜力地区。
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| [28] |
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| [29] |
Theories and methods of space-for-time substitution in geomorphology. https://doi.org/10.11821/dlxb201701008 URL [本文引用: 1] 摘要
地貌的发育在特定的条件下往往呈现空间分布上由“新”至“老”的过渡,据此,对地貌类型与特征在空间上的序列采样,即可为研究某种地貌的个体发育提供基本依据.该方法即为地貌学研究中的空代时.本文首先介绍了空代时方法产生的背景与基本概念.分析了近年来空代时方法应用于河流地貌、构造地貌、河口海岸地貌等不同地貌类型演化过程的研究进展.在此基础上,明确了空代时方法在地貌学研究中的适用条件、影响因素及分类体系,并提出了地貌学空代时的研究范式.本文认为今后的研究工作一方面应充分利用海量的地理空间数据,运用空代时方法研究多种空间尺度下的地貌演化的问题;另一方面,应结合现有的物理机制和统计规律,构建集形、数、理一体化的地貌演化模型.
地貌发育演化研究的空代时理论与方法 .https://doi.org/10.11821/dlxb201701008 URL [本文引用: 1] 摘要
地貌的发育在特定的条件下往往呈现空间分布上由“新”至“老”的过渡,据此,对地貌类型与特征在空间上的序列采样,即可为研究某种地貌的个体发育提供基本依据.该方法即为地貌学研究中的空代时.本文首先介绍了空代时方法产生的背景与基本概念.分析了近年来空代时方法应用于河流地貌、构造地貌、河口海岸地貌等不同地貌类型演化过程的研究进展.在此基础上,明确了空代时方法在地貌学研究中的适用条件、影响因素及分类体系,并提出了地貌学空代时的研究范式.本文认为今后的研究工作一方面应充分利用海量的地理空间数据,运用空代时方法研究多种空间尺度下的地貌演化的问题;另一方面,应结合现有的物理机制和统计规律,构建集形、数、理一体化的地貌演化模型.
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The use of chronosequences in studies of ecological succession and soil development. https://doi.org/10.1111/j.1365-2745.2010.01664.x URL [本文引用: 1] 摘要
1. Chronosequences and associated space-for-time substitutions are an important and often necessary tool for studying temporal dynamics of plant communities and soil development across multiple time-scales. However, they are often used inappropriately, leading to false conclusions about ecological patterns and processes, which has prompted recent strong criticism of the approach. Here, we evaluate when chronosequences may or may not be appropriate for studying community and ecosystem development.2. Chronosequences are appropriate to study plant succession at decadal to millennial time-scales when there is evidence that sites of different ages are following the same trajectory. They can also be reliably used to study aspects of soil development that occur between temporally linked sites over time-scales of centuries to millennia, sometimes independently of their application to shorter-term plant and soil biological communities.3. Some characteristics of changing plant and soil biological communities (e.g. species richness, plant cover, vegetation structure, soil organic matter accumulation) are more likely to be related in a predictable and temporally linear manner than are other characteristics (e.g. species composition and abundance) and are therefore more reliably studied using a chronosequence approach.4. Chronosequences are most appropriate for studying communities that are following convergent successional trajectories and have low biodiversity, rapid species turnover and low frequency and severity of disturbance. Chronosequences are least suitable for studying successional trajectories that are divergent, species-rich, highly disturbed or arrested in time because then there are often major difficulties in determining temporal linkages between stages.5. Synthesis. We conclude that, when successional trajectories exceed the life span of investigators and the experimental and observational studies that they perform, temporal change can be successfully explored through the judicious use of chronosequences.
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Accelerated soil formation due to paddy management on marshlands (Zhejiang Province, China) .https://doi.org/10.1016/j.geoderma.2013.09.005 URL [本文引用: 1] 摘要
61Paddy soil formation was accelerated relative to pedogenesis in non-flooded systems.61Paddy soil formation on marshlands can be subdivided into three time phases.61Paddy soil formation is differentiated in topsoil and subsoil time domains.
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Chronosequence of paddy soils and phosphorus sorption-desorption properties .https://doi.org/10.1007/s11368-010-0301-8 URL 摘要
Purpose Accumulated soil phosphorus (P) in agricultural lands due to long-term organic manure and mineral phosphate fertilizer input is considered one of the main non-point pollution sources to surrounding surface water bodies. A chronosequence of soils is a potent instrument for pedological investigation and allows assessment of the effect of duration of agricultural cultivation on the environmental risk to water bodies of P loss from soil. Materials and methods The present study was conducted to evaluate the impact of pedogenesis on the retention of P in a chronosequence (25, 100, 300, 700, and 2,00002years) of rice paddy soils located on the south bank of Hangzhou Bay. Batch sorption–desorption experiments were performed on the samples of surface horizons from this chronosequence. Results and discussion P retention differed moderately among the studied soils ranging from 17.8% to 22.6% when 2,50002mg02P02kg 611 was added. Subsequent desorption experiment revealed that 11.2% to 21.9% of the recently sorbed P might move into solution. The maximum P sorption capacity as estimated by Langmuir isotherm ranged from 521.9 to 850.902mg02kg 611 , with a mean value of 726.202mg02kg 611 , while the degree of P saturation was less than 5%. The results indicate that P sorption is influenced by soil development with the maximum sorption capacity of studied soils significantly positively correlated to the organic carbon content of these soil materials. Conclusions The pH of the soil decreased from alkaline to neutral with increasing duration of rice cultivation due to continuing decalcification. The organic carbon content in the paddy surface soil materials increased with increasing duration of rice cultivation. The maximum P sorption capacity also slightly increased with increasing duration of rice cultivation likely due to organic carbon accumulation in topsoils. There is a very low risk of P in these paddy soils moving to the surrounding surface water bodies. This study of some possible long-term impacts helps to indicate that rice paddy agriculture is an environment friendly and sustainable land use.
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Spatial variation of carbon, nitrogen and phosphorous in tidal salt marsh soils of the Minjiang River estuary. https://doi.org/10.11821/yj2010070006 URL [本文引用: 2] 摘要
以闽江口区最大的鳝鱼滩潮汐盐沼湿地为研究对象,选择远、近潮沟区2个不同潮水水淹地段设置样线,采集3种优势植物芦苇(Phragmites australis)、咸草(Cyperus malac-censisvar.bervifolius)和藨草(Scirpus triqueter)下18个土壤剖面分层样品,分析土壤中DOC、TN和TP等含量和储量的空间分布规律及土壤物理特征对其的影响。结果表明:远、近潮沟区3种植物下土壤表层(0~10 cm)TN浓度范围为0.24~1.91g kg-1,TP为0.21~1.34 g kg-1,DOC为13.68~93.73 mg kg-1,无论是近潮沟区还是远潮沟区,芦苇和咸草下土壤DOC、TN和TP含量十分接近,且均大于藨草下土壤DOC、TN含量,藨草下土壤TN和TP含量和储量在近潮沟区均明显大于远潮沟区,而芦苇和咸草下土壤TN和TP含量在远、近潮沟区差距不大;土壤DOC、TN和TP含量与土壤粒径、容重和含水量呈显著相关,盐度对土壤中NH4+-N和NO3--N含量影响显著,与NH4+-N为正相关关系,与NO3--N为负相关关系。
闽江口潮汐盐沼湿地土壤碳氮磷的空间变化 .https://doi.org/10.11821/yj2010070006 URL [本文引用: 2] 摘要
以闽江口区最大的鳝鱼滩潮汐盐沼湿地为研究对象,选择远、近潮沟区2个不同潮水水淹地段设置样线,采集3种优势植物芦苇(Phragmites australis)、咸草(Cyperus malac-censisvar.bervifolius)和藨草(Scirpus triqueter)下18个土壤剖面分层样品,分析土壤中DOC、TN和TP等含量和储量的空间分布规律及土壤物理特征对其的影响。结果表明:远、近潮沟区3种植物下土壤表层(0~10 cm)TN浓度范围为0.24~1.91g kg-1,TP为0.21~1.34 g kg-1,DOC为13.68~93.73 mg kg-1,无论是近潮沟区还是远潮沟区,芦苇和咸草下土壤DOC、TN和TP含量十分接近,且均大于藨草下土壤DOC、TN含量,藨草下土壤TN和TP含量和储量在近潮沟区均明显大于远潮沟区,而芦苇和咸草下土壤TN和TP含量在远、近潮沟区差距不大;土壤DOC、TN和TP含量与土壤粒径、容重和含水量呈显著相关,盐度对土壤中NH4+-N和NO3--N含量影响显著,与NH4+-N为正相关关系,与NO3--N为负相关关系。
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| [34] |
Spatial distribution and seasonal dynamics characteristics of carbon, nitrogen, and phosphorous in the Liaohe estuary wetlands. 辽河口湿地碳、氮、磷空间分布及季节动态特征 . |
| [35] |
Geochemical characteristics of the sediment elements and its environmental efficiencies in the Liaohe River Estuary [D]. 辽河口潮滩沉积物元素地球化学特征及其环境效应 [D]. |
| [36] |
Spatiotemporal distribution characteristics of soil organic carbon in newborn coastal wetlands of the Yellow River Delta estuary .https://doi.org/10.1002/clen.201100511 URL [本文引用: 1] 摘要
The distribution and seasonal variation of soil organic carbon (SOC) in newborn coastal wetland of the Yellow River Delta (YRD) estuary at eastern China were studied based on monitoring data in 2009 at two transects from the bank of the Yellow River to the seaside. The results showed that SOC contents of 0–6065cm soil layer in transects ranged from 0.46 to 10.1565g65kg611 and average values of soil profiles ranged from 2.15 to 5.0065g65kg611. The SOC contents tended to increase from the river flood land to the salt beach, which could be accounted for the organic matters including large algae, the bodies and excretion of marine animals due to the feedback of tides. The significant difference of SOC contents at different vegetation communities was observed, while the difference of SOC in soil profiles was not obvious. The SOC contents in 0–3065cm soil layers decreased with plant growth period, while in 40–6065cm soil layers were relatively stable. The mean soil organic carbon density was 3.0565kg65C65m612 in study region, which was much lower than that reported in other ecosystems, and its spatiotemporal variations were consistent with that of SOC content. Further analysis revealed that SOC was positively correlated with total nitrogen and clay contents. Our findings indicated that the newborn coastal wetland in the YRD should be a potential sink of SOC.
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| [37] |
Spatial distribution of phosphorous and nitrogen in core sediments of Bohai bay .https://doi.org/10.3321/j.issn:1671-9387.2005.04.025 URL [本文引用: 1] 摘要
对2003-07在渤海湾采集的柱状沉积物中氮、磷的分布进行研究。结果表明,渤海湾柱状沉积物中氮、磷空间分布特征是近岸高,远岸低;近岸P含量达0.410mg/g,远岸含量为0.233mg/g。其中磷主要以无机磷形式存在,无机磷约占总磷的50%以上;渤海湾沉积物中氮含量较高,平均达5.96mg/g。
渤海湾沉积物中氮、磷的空间分布特征研究 .https://doi.org/10.3321/j.issn:1671-9387.2005.04.025 URL [本文引用: 1] 摘要
对2003-07在渤海湾采集的柱状沉积物中氮、磷的分布进行研究。结果表明,渤海湾柱状沉积物中氮、磷空间分布特征是近岸高,远岸低;近岸P含量达0.410mg/g,远岸含量为0.233mg/g。其中磷主要以无机磷形式存在,无机磷约占总磷的50%以上;渤海湾沉积物中氮含量较高,平均达5.96mg/g。
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| [38] |
Correlation between soil pH and nutrients of tidal flat reclamation with different years in Rudong County. https://doi.org/10.1870/cjlyzyyhj201402010 URL Magsci [本文引用: 1] 摘要
<p>滩涂围垦是沿海地区开拓土地资源和缓解人地矛盾的重要措施，土壤环境也因此发生剧烈变化。以江苏如东县沿海不同年限的垦区土壤为研究对象，探讨土壤pH值、有机质和氮、磷、钾速效养分的分布情况，pH值、有机质和速效养分之间的关系，以及这种相关性随垦区围垦年限而发生的变化。结果表明：如东滩涂围垦区土壤呈碱性，土壤养分较为缺乏；随着围垦年限的增加，垦区土壤pH值下降，土壤养分呈增加趋势，垦区围垦年限对土壤pH值、有机质与速效养分之间的相关性存在一定影响，其中10 a围垦期是pH与有机质、速效磷之间相关性变化的转折点。围垦年限不仅对垦区土壤pH值、土壤有机质和速效养分的绝对含量有着明显影响，还影响土壤pH值、有机质与土壤速效养分之间的相关关系，随着垦区围垦年限的增加，人为活动影响程度加深，土壤逐渐从自然的滨海盐土向农业土壤演化，土壤要素间的相关关系逐渐向一般耕作土壤靠近</p>
如东县不同年限滩涂围垦区土壤pH与养分相关性研究 .https://doi.org/10.1870/cjlyzyyhj201402010 URL Magsci [本文引用: 1] 摘要
<p>滩涂围垦是沿海地区开拓土地资源和缓解人地矛盾的重要措施，土壤环境也因此发生剧烈变化。以江苏如东县沿海不同年限的垦区土壤为研究对象，探讨土壤pH值、有机质和氮、磷、钾速效养分的分布情况，pH值、有机质和速效养分之间的关系，以及这种相关性随垦区围垦年限而发生的变化。结果表明：如东滩涂围垦区土壤呈碱性，土壤养分较为缺乏；随着围垦年限的增加，垦区土壤pH值下降，土壤养分呈增加趋势，垦区围垦年限对土壤pH值、有机质与速效养分之间的相关性存在一定影响，其中10 a围垦期是pH与有机质、速效磷之间相关性变化的转折点。围垦年限不仅对垦区土壤pH值、土壤有机质和速效养分的绝对含量有着明显影响，还影响土壤pH值、有机质与土壤速效养分之间的相关关系，随着垦区围垦年限的增加，人为活动影响程度加深，土壤逐渐从自然的滨海盐土向农业土壤演化，土壤要素间的相关关系逐渐向一般耕作土壤靠近</p>
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| [39] |
The effect of tidal flat reclamation and development on grain production capacity in the Jiangsu coastal zone [D].
江苏沿海滩涂围垦对粮食产能的影响研究[D] .
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| [40] |
Phosphorous distribution in soils and sediments from coastal areas in eastern China [D]. 华东沿海典型滩涂区土壤和沉积物磷分布特征[D] . |
| [41] |
Effects of reclamation on tidal flat and land use on soil microbial community. https://doi.org/10.5846/stxb201305271198 Magsci [本文引用: 1] 摘要
土壤微生物在生态系统营养物质循环过程，特别是碳、氮循环过程中扮演着重要的角色。上海市崇明岛位于长江入海口，因其土壤发育时间较短、土地利用历史背景清晰、土壤本底均一，不同土壤围垦年代的土壤，代表了土壤发育年代的不同时期。以空间变化代替时间变化，对崇明岛稻田和旱地6个不同围垦年代土壤的磷酸脂肪酸（PLFA）指纹图谱研究表明，湿地滩涂围垦16a后土壤微生物总PLFA、细菌PLFA、革兰氏阳性菌（G<sup>+</sup>） PLFA和革兰氏阴性菌（G<sup>-</sup>） PLFA含量显著降低。随着围垦时间的逐步增加，PLFA含量逐步上升。经过长时间的农业种植，G<sup>+</sup> PLFA在围垦120a和300a稻田和旱地土壤中没有显著性差异；而总PLFA、细菌和G<sup>-</sup> PLFA在围垦75、120a和300a的土壤中含量趋于稳定且没有显著性差异。围垦16a和40a稻田土壤中总PLFA和G<sup>+</sup> PLFA显著高于旱地土壤；围垦40a稻田土壤中细菌和G<sup>-</sup> PLFA显著高于旱地土壤。不同围垦年代土壤总PLFA、细菌PLFA与土壤总氮、粘土含量成显著的正相关关系。河口湿地围垦后微生物数量的变化与土壤营养含量存在强烈相关关系，提示土壤围垦及演替过程中微生物与土壤肥力之间的紧密关系，对探讨土壤演替过程中微生物群落的变化具有重要意义。
滩涂围垦和土地利用对土壤微生物群落的影响 .https://doi.org/10.5846/stxb201305271198 Magsci [本文引用: 1] 摘要
土壤微生物在生态系统营养物质循环过程，特别是碳、氮循环过程中扮演着重要的角色。上海市崇明岛位于长江入海口，因其土壤发育时间较短、土地利用历史背景清晰、土壤本底均一，不同土壤围垦年代的土壤，代表了土壤发育年代的不同时期。以空间变化代替时间变化，对崇明岛稻田和旱地6个不同围垦年代土壤的磷酸脂肪酸（PLFA）指纹图谱研究表明，湿地滩涂围垦16a后土壤微生物总PLFA、细菌PLFA、革兰氏阳性菌（G<sup>+</sup>） PLFA和革兰氏阴性菌（G<sup>-</sup>） PLFA含量显著降低。随着围垦时间的逐步增加，PLFA含量逐步上升。经过长时间的农业种植，G<sup>+</sup> PLFA在围垦120a和300a稻田和旱地土壤中没有显著性差异；而总PLFA、细菌和G<sup>-</sup> PLFA在围垦75、120a和300a的土壤中含量趋于稳定且没有显著性差异。围垦16a和40a稻田土壤中总PLFA和G<sup>+</sup> PLFA显著高于旱地土壤；围垦40a稻田土壤中细菌和G<sup>-</sup> PLFA显著高于旱地土壤。不同围垦年代土壤总PLFA、细菌PLFA与土壤总氮、粘土含量成显著的正相关关系。河口湿地围垦后微生物数量的变化与土壤营养含量存在强烈相关关系，提示土壤围垦及演替过程中微生物与土壤肥力之间的紧密关系，对探讨土壤演替过程中微生物群落的变化具有重要意义。
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| [42] |
Effect of long-term reclamation on soil properties on a coastal plain, southeast China. https://doi.org/10.2112/JCOASTRES-D-13-00129.1 URL [本文引用: 1] 摘要
The coastal plain of Cixi City, in southeast China, has experienced more than a thousand years of land reclamation history. Since 1047, 11 dikes have been built, dividing our study region into 11 zones. The main aim of this study was to evaluate the effects of long-term reclamation on the variability of soil properties. Using an integrated transect and nested sampling approach, a total of 329 surface soil samples were collected. Soil pH, organic matter, electrical conductivity, and particle size distribution were measured. Data were evaluated using classical statistics and geostatistics methods. Results indicate that reclamation exerted quantifiable effects on various soil attributes. There were significant differences in soil properties among the zones. The ranges in semivariograms were approximately equal to or twice the average zone span, suggesting that there was usually a break in continuity of soil properties at the boundary of reclamation zones. As illustrated by the lower nugget effect or larger range distance in semivariograms, soil pH, electrical conductivity, and organic matter similarly showed more continuous patterns in space compared with particle size distribution. With the increase of time since reclamation, salt content, alkalinity, and particle size tended to decrease, while organic matter content tended to increase. Most properties varied greatly in the initial reclamation stages. A relatively steady state was reached within 10 years following the reclamation for pH, about 30 years for organic matter, and 60 years for electrical conductivity, respectively. Further, similar land uses and parent materials produced similar inherent soil properties. These findings can be applied to broader spatial scales in other coastal regions to assist in transitioning from a coastal tidal plain to productive agricultural land, through reclamation, and targeted land management practices.
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| [43] |
Short-term variation of soil chemical properties after tidal flat reclamation in a typical coastal area. 典型滩涂围垦区土壤化学性质的短期变化特征 . |
| [44] |
Heavy metals content and distribution in the surface sediments of the Guangzhou section of the Pearl River, Southern China. https://doi.org/10.1007/s12665-011-1172-z URL [本文引用: 1] 摘要
The long-term industrialization and urbanization of Guangzhou city may lead to heavy metal contamination of its aquatic sediment. Nevertheless, only few studies have been published on the distribution and contamination assessment of heavy metals in this urban river sediment. Thus, the major objective of this study was to quantitatively assess contamination of heavy metals and their chemical partitioning in the sediments of the Guangzhou section of the Pearl River (GSPR). Surface sediment samples were collected at 10 sites in the main river and 12 sites in the creeks of the GSPR. The total content of Cd was determined by graphite furnace atomic adsorption spectrometry (GF-AAS), and content of Cr, Cu, Pb and Zn was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The chemical partitioning of these heavy metals in the sediments of the main river was determined by the sequential selective extraction (SSE) method. Results indicated that the average total concentrations of Cd, Cr, Pb, Cu and Zn in the sediments of the main river were 1.44, 63.7, 95.5, 253.6 and 370.0 mg/kg, respectively, whereas they were 2.10, 125.5, 110.1, 433.7 and 401.9 mg/kg in the sediments of the creeks. The sediment at M4 and C9 sites was heavily contaminated with about 8 and 11 of toxic unit, respectively. Cr, Cu, Pb and Zn were mostly bound to organic matter and in the residual phase, whereas Cd was mostly associated with the soluble and exchangeable phase and the residual phase. The mobility and bioavailability of Cd, Zn and Cr in the sediments of the main river were relatively higher than Cu and Pb, due to higher levels in the soluble and exchangeable fraction and the carbonate fraction. The potential acute toxicity in the sediments of the main river and creeks was mainly caused by Cu contamination, accounting for 21.7 37.1% and 16.9 46.3% of the total toxicity, respectively, followed by Zn and Pb. Adverse biological effects induced by heavy metals would be expected in the sediments of the GSPR. Therefore, the sediments of the GSPR, especially at M4 and C9 sites, need to be remediated to maintain aquatic ecosystem health.
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| [45] |
Species of phosphorous in sediments from Pearl River estuary. https://doi.org/10.3969/j.issn.1007-6336.2001.04.006 URL [本文引用: 1] 摘要
采用较为系统的化学提取法,对珠江口柱状沉积物中TP、各形态无机磷及有机磷进行分析,重点考虑了分离提取碎屑和自生钙结合磷.结果表明:在无机磷中以钙结合磷占主要地位(49%),其中又以碎屑磷含量较高(43%),有机磷含量在TP中占有一定比例(38.8%). 沉积物中TP及其不同形态无机磷在垂向上的分布变化规律为:TP、有机磷和Fe-P含量随深度增加而降低,而碎屑态磷含量随深度增加而增高,自生钙磷变化幅度不大.TP、有机磷和Fe -P含量自下而上增高,在一定程度上反映了近年来陆源环境污染加剧的趋势.综合调查区域各种理化条件,认为在珠江口仅有铁结合磷与有机磷为潜在的生物可利用P,自生钙结合磷与原生碎屑结合磷总的来说占沉积物中TP的49%,因此我们可估计有将近一半的P不能为生物利用.
珠江口沉积物中磷的赋存形态 .https://doi.org/10.3969/j.issn.1007-6336.2001.04.006 URL [本文引用: 1] 摘要
采用较为系统的化学提取法,对珠江口柱状沉积物中TP、各形态无机磷及有机磷进行分析,重点考虑了分离提取碎屑和自生钙结合磷.结果表明:在无机磷中以钙结合磷占主要地位(49%),其中又以碎屑磷含量较高(43%),有机磷含量在TP中占有一定比例(38.8%). 沉积物中TP及其不同形态无机磷在垂向上的分布变化规律为:TP、有机磷和Fe-P含量随深度增加而降低,而碎屑态磷含量随深度增加而增高,自生钙磷变化幅度不大.TP、有机磷和Fe -P含量自下而上增高,在一定程度上反映了近年来陆源环境污染加剧的趋势.综合调查区域各种理化条件,认为在珠江口仅有铁结合磷与有机磷为潜在的生物可利用P,自生钙结合磷与原生碎屑结合磷总的来说占沉积物中TP的49%,因此我们可估计有将近一半的P不能为生物利用.
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| [46] |
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| [47] |
Soil parent material: A major driver of plant nutrient limitations in terrestrial ecosystems. https://doi.org/10.1111/gcb.13691 URL PMID: 28317232 [本文引用: 1] 摘要
Because the capability of terrestrial ecosystems to fix carbon is constrained by nutrient availability, understanding how nutrients limit plant growth is a key contemporary question. However, what drives nutrient limitations at global scale remains to be clarified. Using global data on plant growth, plant nutritive status, and soil fertility, we investigated to which extent soil parent materials explain nutrient limitations. We found that N limitation was not linked to soil parent materials, but was best explained by climate: ecosystems under harsh (i.e., cold and or dry) climates were more N-limited than ecosystems under more favourable climates. Contrary to N limitation, P limitation was not driven by climate, but by soil parent materials. The influence of soil parent materials was the result of the tight link between actual P pools of soils and physical hemical properties (acidity, P richness) of soil parent materials. Some other ground-related factors (i.e., soil weathering stage, landform) had a noticeable influence on P limitation, but their role appeared to be relatively smaller than that of geology. The relative importance of N limitation versus P limitation was explained by a combination of climate and soil parent material: at global scale, N limitation became prominent with increasing climatic constraints, but this global trend was modulated at lower scales by the effect of parent materials on P limitation, particularly under climates favourable to biological activity. As compared with soil parent materials, atmospheric deposition had only a weak influence on the global distribution of actual nutrient limitation. Our work advances our understanding of the distribution of nutrient limitation at global scale. In particular, it stresses the need to take soil parent materials into account when investigating plant growth response to environment changes.
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| [48] |
Analysis of the atmospheric deposition of nitrogen and phosphorous: Taking with Beili Lake as an example. https://doi.org/10.13637/j.issn.1009-6094.2015.03.066 URL [本文引用: 1] 摘要
为更好地了解大气氮磷沉降量的影响因素及其对水环境的影响,采用自制采样器,对杭州北里湖2011年4月—2012年2月大气氮、磷的总、湿沉降进行采集,并通过对干、湿沉降量的计算,探讨了大气干、湿沉降中TN、TP、NH+4-N和NO-3-N的变化趋势。结果表明,因秋季利于沉降而不利于扩散,夏季降水多,各物质的干沉降量表现出秋季高、夏季低的特点,湿沉降量则夏季较高。TN干沉降以NH+4-N为主,其干沉降量与气温、气压及降水量有关,而NO-3-N干沉降量与风速有关;大气湿沉降量除NO-3-N外,TN、TP和NH+4-N与降水量均呈现出较强的相关性,相关系数分别为0.882、0.700和0.827。在研究期间,TN、NH+4-N和NO-3-N以湿沉降为主,TP以干沉降为主;北里湖大气总沉降的入湖TN量为4 503.74 kg/km2,TP为100.14 kg/km2,入湖的TN/TP比值高达45,远超出正常水平,这对北里湖水体的富营养化产生了严重影响。
大气氮磷沉降量分析: 以杭州北里湖为例 .https://doi.org/10.13637/j.issn.1009-6094.2015.03.066 URL [本文引用: 1] 摘要
为更好地了解大气氮磷沉降量的影响因素及其对水环境的影响,采用自制采样器,对杭州北里湖2011年4月—2012年2月大气氮、磷的总、湿沉降进行采集,并通过对干、湿沉降量的计算,探讨了大气干、湿沉降中TN、TP、NH+4-N和NO-3-N的变化趋势。结果表明,因秋季利于沉降而不利于扩散,夏季降水多,各物质的干沉降量表现出秋季高、夏季低的特点,湿沉降量则夏季较高。TN干沉降以NH+4-N为主,其干沉降量与气温、气压及降水量有关,而NO-3-N干沉降量与风速有关;大气湿沉降量除NO-3-N外,TN、TP和NH+4-N与降水量均呈现出较强的相关性,相关系数分别为0.882、0.700和0.827。在研究期间,TN、NH+4-N和NO-3-N以湿沉降为主,TP以干沉降为主;北里湖大气总沉降的入湖TN量为4 503.74 kg/km2,TP为100.14 kg/km2,入湖的TN/TP比值高达45,远超出正常水平,这对北里湖水体的富营养化产生了严重影响。
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| [49] |
Spatial change and affecting factors of soil carbon exchange capacity in Tibet. https://doi.org/10.3321/j.issn:1009-2242.2004.05.001 URL [本文引用: 1] 摘要
根据西藏17个土类150个骨干剖面的分析资料,应用统计方法,探讨土壤CEC的空间变化和影响因素.结果表明,在西藏广阔的高原面上,土壤CEC的空间变化具有明显的水平地带特征:从东南向西北,土壤CEC随高山草甸型→高山草原型→高山荒漠型而急剧降低.土壤CEC垂直变化亦有表现,特别是在藏东南地区,山地湿润森林土壤的CEC从基带黄壤向上增高,至暗棕壤和灰化土达到最高,而在森林线以上土壤CEC又随黑毡土→草毡土→寒冻土而降低.西藏土壤CEC的空间变化,主要决定于各类土壤有机质积累的差异;有机质含量较低的土壤,粘粒含量也有重要影响;高山草甸型土壤还受粉砂粒含量的影响.土壤速效钾含量与CEC呈显著正相关,显示了土壤CEC的重要保钾功能.
西藏土壤阳离子交换量的空间变化和影响因素研究 .https://doi.org/10.3321/j.issn:1009-2242.2004.05.001 URL [本文引用: 1] 摘要
根据西藏17个土类150个骨干剖面的分析资料,应用统计方法,探讨土壤CEC的空间变化和影响因素.结果表明,在西藏广阔的高原面上,土壤CEC的空间变化具有明显的水平地带特征:从东南向西北,土壤CEC随高山草甸型→高山草原型→高山荒漠型而急剧降低.土壤CEC垂直变化亦有表现,特别是在藏东南地区,山地湿润森林土壤的CEC从基带黄壤向上增高,至暗棕壤和灰化土达到最高,而在森林线以上土壤CEC又随黑毡土→草毡土→寒冻土而降低.西藏土壤CEC的空间变化,主要决定于各类土壤有机质积累的差异;有机质含量较低的土壤,粘粒含量也有重要影响;高山草甸型土壤还受粉砂粒含量的影响.土壤速效钾含量与CEC呈显著正相关,显示了土壤CEC的重要保钾功能.
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| [50] |
Spatial variation of soil salinity in the coastal reclamation area, eastern China. https://doi.org/10.2112/JCOASTRES-D-13-00078.1 URL [本文引用: 3] 摘要
Reclamation of coastal saline tidal flats has become a common practice for coastal countries faced with a decrease in cultivated land and an increase in population. Because the variability of soil salinity is considerable, understanding the spatial distribution of this salinity and its components is essential for land use planning. This study was conducted in a coastal area in eastern China that has been reclaimed under various land use types at different times. The objective of the work was to assess the effect of the reclamation time and land use types on soil salinity and spatial variation of soil salinity by using conventional statistics and geostatistical techniques. The results indicate that reclamation times and land use types significantly influence soil salinity in coastal areas. Cropland and aquaculture pond have same effect on soil desalinization. Soil desalinization reached a balance after 30 years. According to the average soil salinity at the depth of 0-40 cm and soil salinity spatial stability of soil profile, the study area is divided into eight management zones, which is useful for soil sampling investigation and making decisions on the kind of crops that can be cultivated at the different fields of the study area.
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| [51] |
Salinity evolution of coastal soils following reclamation and intensive usage, Eastern China. https://doi.org/10.1007/s12665-016-6095-2 URL 摘要
Salinity is the main limiting factor for agriculture development in coastal areas. Knowledge of the spatial distribution and temporal evolution of soil salinity following reclamation is of great impor
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| [52] |
Characteristic of soil profile salt in tidal flats under different reclamation years in Jiangsu Province.
通过引入聚集系数、变异系数和分形维数等参数揭示了不同围垦年限下的沿海滩涂土壤剖面盐分和粒径的分布特征,并且运用灰色关联度方法计算了土壤盐分与土壤粒径的相关联程度,结果发现:①随着围垦年限和人类活动强度的增加,沿海滩涂土壤中总体盐分含量逐渐下降,且表现出有农作物生长的田间的脱盐效果明显快于、好于无农作物生长的田边土壤。同时沿海滩涂土壤经历了"均匀型-表聚型-震荡型-底聚型-震荡型-均匀型"的变化趋势;②围垦20～60a的无盐土盐分处于临界轻度盐化土的状态,土壤次生盐碱化风险较高;③沿海滩涂土壤各层盐分表现出"临层相关-隔层相关-上层相关"的变化过程,各层与平均含盐量的相关性体现了土壤剖面含盐量向均匀型转变的特征;④土壤粒径逐渐变小,土壤肥力逐渐增加,并且有作物生长的田中央增加速度大于田边。土壤盐分与土壤粒径的关联度总体不强,粒径对土壤盐分的影响弱于人类活动。
江苏沿海不同时期滩涂围垦区土壤剖面盐分特征分析: 以江苏省如东县为例 .
通过引入聚集系数、变异系数和分形维数等参数揭示了不同围垦年限下的沿海滩涂土壤剖面盐分和粒径的分布特征,并且运用灰色关联度方法计算了土壤盐分与土壤粒径的相关联程度,结果发现:①随着围垦年限和人类活动强度的增加,沿海滩涂土壤中总体盐分含量逐渐下降,且表现出有农作物生长的田间的脱盐效果明显快于、好于无农作物生长的田边土壤。同时沿海滩涂土壤经历了"均匀型-表聚型-震荡型-底聚型-震荡型-均匀型"的变化趋势;②围垦20～60a的无盐土盐分处于临界轻度盐化土的状态,土壤次生盐碱化风险较高;③沿海滩涂土壤各层盐分表现出"临层相关-隔层相关-上层相关"的变化过程,各层与平均含盐量的相关性体现了土壤剖面含盐量向均匀型转变的特征;④土壤粒径逐渐变小,土壤肥力逐渐增加,并且有作物生长的田中央增加速度大于田边。土壤盐分与土壤粒径的关联度总体不强,粒径对土壤盐分的影响弱于人类活动。
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| [53] |
Dynanmics of soil salt content in platform fields in Yangkou port of Jiangsu Province. 江苏洋口港台田土壤盐分动态变化特征研究 . |
| [54] |
Study on the increasing of pH value of seashore saline soil during its desalting in Jiangsu Province. 江苏省滨海盐土脱盐过程pH值上升原因的探讨 . |
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