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以川东北巴中市为例,采用实地采样法和室内测定法,对土壤Se含量及其分布做了研究,以促进其现代农业的发展,合理选择优势作物。结果表明:不同土壤类型Se含量:黄棕壤 > 黄壤 > 紫色土壤。黄壤不同土地利用类型Se含量:其他用地 > 农田 > 蔬菜地;黄棕壤不同土地利用类型Se含量:蔬菜地 > 其他用地 > 林地 > 农田 > 旱地 > 果园地;紫色土壤不同土地利用类型Se含量:农田 > 果园地 > 旱地 > 蔬菜地 > 其他用地。黄壤不同耕作制度类型Se含量:旱作地 > 水耕地;黄棕壤不同耕作制度类型Se含量:水耕地 > 旱作地 > 水旱地;紫色土壤不同耕作制度类型Se含量:水旱地 > 旱作地。不同地域土壤剖面中Se元素含量:通江县 > 南江县 > 巴州区 > 平昌县。巴中市Se含量平均值为0.165 μg/g,低于全国平均值。四个富硒产业带分别为:通江县富硒马铃薯产业带;南江县富硒金银花产业带;南江县富硒蔬菜产业带;南江县富硒茶叶产业带。马铃薯、金银花、茶叶均为巴中的富硒优势作物。 相似文献
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花江喀斯特石漠化区不同经济型植物的土壤蓄水特征 总被引:2,自引:0,他引:2
选择贵州省花江喀斯特石漠化综合治理区分布广泛的几种典型生态经济型种植模式花椒、金银花、砂仁、火龙果、构树、花椒金银花混交林为研究对象,以荒草地为对照,对各植物的土壤物理性质和蓄水性能进行了对比研究。结果表明:(1)研究区土壤容重的浮动范围为1.09~1.40 g/cm3,并随土层深度增加而增加;孔隙度随土层深度增加而减小,上层土壤的蓄水性能和通透性能优于下层。(2)与荒草地相比,构树、火龙果、花椒金银花混交林、花椒、金银花的土壤容重和孔隙度状况都优于荒草地,只有砂仁比荒草地差。(3)从土壤含水量和0—30 m总蓄水量来看,混交林土壤含水量最大(37.69%),分别比金银花、火龙果、构树、花椒、荒草地、砂仁高3.18%,4.33%,4.83%,7.49%,10.15%,13.18%;总蓄水量表现为花椒金银花混交林(1 769.54 t/hm2) > 火龙果(1 732.94 t/hm2) > 构树(1 722.14 t/hm2) > 花椒(1 698.43 t/hm2) > 金银花(1 655.58 t/hm2) > 荒草地(1 640.79 t/hm2) > 砂仁(1 428.75 t/hm2)。(4)相关分析表明土壤容重和毛管孔隙度与最大持水率及毛管持水率均呈极显著相关(p < 0.01),相关系数分别为-0.931,0.897,-0.915,0.890。因此,在花江喀斯特石漠化植被恢复过程中应优先考虑以花椒金银花为代表的混交林与火龙果模式。 相似文献
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测土配方施肥对金银花产量和质量的影响 总被引:1,自引:0,他引:1
《核农学报》2017,(12)
为探讨氮、磷、钾肥对金银花产量和质量的影响,在山东临沂地区开展金银花测土配方施肥试验,设计了3个肥料因素(N、P_2O_5、K_2O),4个施肥水平(0水平:不施肥;1水平:常用施肥量0.5倍;2水平:常用施肥量;3水平:常用施肥量1.5倍),共14种配比施肥处理。结果表明,施肥处理对金银花产量的影响极显著,处理N_2P_3K_2的产量最高为391.8 g,比不施肥产量增加了37.6%;每施1 g氮、磷、钾肥分别能增加花蕾产量1.98、8.21、4.56 g;拟合了金银花单株产量与氮、磷、钾肥的肥料效应方程,其推荐施肥量为N、P_2O_5、K_2O分别施34.9~47.9、13.1~14.4、18.5~23.8 g,此时单株产量为387.0~430.3 g;氮、磷、钾肥与花蕾长度均呈正相关,其中磷肥效果显著,说明磷肥是影响千蕾重和产量的主要肥力因子,是花蕾生长发育的关键元素;不同施肥处理中,磷肥与绿原酸含量表现为正相关,且影响显著;磷肥和钾肥的协同作用与木犀草苷含量呈正相关。本研究结果为金银花氮、磷、钾合理配方施肥提供了理论参考。 相似文献
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通渭县从2013年开始,引进了名贵中药材金银花在全县不同气候条件区域进行试验种植。以试验点的种植情况、经济效益、质量安全评价等为依据,对通渭县金银花种植前景进行了研究,结果表明:金银花在通渭县海拔2 100 m以下、年均气温6℃以上、年降水量400 mm左右的地区可大面积推广种植,且通渭县种植的金银花主要成分绿原酸和木犀草苷含量高于原产地山东平邑和《中国药典》标准,铅、镉、铜3种重金属含量低于原产地和《中国药典》标准。因此,金银花在通渭县具有广阔的发展前景,是当地农民增收致富的又一新型产业。 相似文献
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为进一步研究植物篱在防控果园水土流失方面的效果,以赣南典型脐橙园梯壁裸露小区为对照,分析了种植金银花植物篱小区的水土保持综合效益。结果表明:梯壁种植金银花小区土壤>0.25 mm大团聚体比梯壁裸露小区有所提高;梯壁种植金银花2 a后土壤结构体破坏率比同年限梯壁裸露小区土壤降低了58.82%,WSA提高了19.63%;与梯壁裸露小区相比,梯壁种植金银花小区在中雨条件下减沙效益为20.89%,总氮、总磷流失量分别减少30.49%、35.00%,大雨条件下减沙效益可达73.49%,总氮、总磷流失量分别减少15.97%、59.78%;梯壁种植金银花1 a后土壤有机质、总氮、总磷含量分别比同年限梯壁裸露小区提高8.97%、27.78%和133.33%,种植2 a分别提高16.59%、25.71%和20.00%。因此,脐橙园梯壁种植金银花不仅可以提高土壤团聚体稳定性及土壤抗蚀性,减少土壤及其养分流失,同时还可以培肥土壤,提高其水土保持综合效益。 相似文献
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中国华北地区近40年物候春季变化 总被引:17,自引:4,他引:17
根据华北地区7个观测站物候资料,分析了华北地区1963-1996年及北京1963-2005年物候春季的变化特征及其与气温的关系。结果表明:华北地区的物候春季有明显提早来临的趋势,而造成这一变化的主要因素是本地区近40 a来冬春季气温的明显上升。其中1963-1996年间华北地区1-3月及4月的平均气温分别上升了2.3℃与1.7℃,物候春季起止日期分别提前了9d和4d,因而使得春季长度也延长了5d;北京1963-2003年间1-3月及4月的平均气温分别上升了3.5℃与2.6℃,物候春季的起止日期分别提前了11d和10d,但春季长度没有明显变化。 相似文献
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Sediment denitrification in waterways in a rice-paddy-dominated watershed in eastern China 总被引:1,自引:0,他引:1
Xiaobo Li Yongqiu Xia Yuefei Li Todd M. Kana Sonoko D. Kimura Masanori Saito Xiaoyuan Yan 《Journal of Soils and Sediments》2013,13(4):783-792
Purpose
Rice-paddy-dominated watersheds in eastern China are intensively cultivated, and lands with two crops receive as much as 550–600 kg?ha–1?year–1 of nitrogen (N), mainly through the addition of N-based fertilizers. However, stream N concentrations have been found to be relatively low. Waterways in the watersheds are assumed to be effective “sinks” for N, minimizing its downstream movement. We directly measured net sediment denitrification rates in three types of waterways (ponds, streams/rivers, and a reservoir) and determined the key factors that control net sediment denitrification. Such information is essential for evaluating the impact of the agricultural N cycle on the quality of surface water.Materials and methods
The pond–stream–reservoir continuum was sampled every 2 months at nine sites in an agricultural watershed between November 2010 and December 2011. Net sediment N2 fluxes/net sediment denitrification rates were determined by membrane inlet mass spectrometry and the N2/Ar technique. A suite of parameters known to influence denitrification were also measured.Results and discussion
Net denitrification rates ranged between 28.2?±?18.2 and 674.3?±?314.5 μmol N2–N?m–2?h–1 for the streams, 23.7?±?23.9 and 121.2?±?38.7 μmol N2–N?m–2?h–1 for the ponds, and 41.8?±?17.7 and 239.3?±?49.8 μmol N2–N?m–2?h–1 for the reservoir. The mean net denitrification rate of the stream sites (173.2?±?248.4 μmol N2–N?m–2?h–1) was significantly higher (p?<?0.001) than that of the pond sites (48.3?±?44.5 μmol N2–N?m–2?h–1), and the three types of waterways all had significantly higher (p?<?0.01) mean net denitrification rates in summer than in other seasons. Linear regression and linear mixed effect model analysis showed that nitrate (NO3 ?–N) concentration in surface water was the primary controlling factor for net sediment denitrification, followed by water temperature. Using monitoring data on NO3 ?–N concentrations and temperature of the surface water of waterways and an established linear mixed effect model, total N removed through net sediment denitrification in the pond–stream–reservoir continuum was estimated at 46.8?±?24.0 t?year–1 from July 2007 to June 2009, which was comparable with earlier estimates based on the mass balance method (34.3?±?12.7 t?year–1), and accounted for 83.4 % of the total aquatic N. However, the total aquatic N was only 4.4 % of the total N input to the watershed, and thus most of the surplus N in the watershed was likely to be either denitrified or stored in soil.Conclusions
High doses of N in a rice-paddy-dominated watershed did not lead to high stream N concentrations due to limited input of N into waterways and the high efficiency of waterways in removing N through denitrification. 相似文献13.
天津半干旱地区不同种植年限菜田土壤微生物变化特征的研究 总被引:13,自引:1,他引:12
对天津周边半干旱地区不同种植年限的菜田土壤微生物状况调查研究表明 ,该地区土壤微生物以细菌为主 ,夏季微生物总量大大高于冬季 ;随着种菜年限的增加 ,耕层和亚耕层微生物总量都有增加趋势 ,其中细菌和放线菌增加明显 ,真菌有下降趋势 ;真菌类群分析表明 ,少数纤维素分解菌 ,如青霉 (Penicillium)、木霉 (Trichoderma)等为优势菌 ,而糖和木质素分解菌仅占少数。用尖孢镰刀霉 (Fusariumuoxysporum)、大肠杆菌 (Escherichia coli)接种不同种菜年限土壤 ,检测土壤拮抗菌状况发现 ,拮抗菌仅在种植年限长的老菜田的放线菌中发现。表明北方半干旱地区菜田土壤细菌为优势菌 ,主要存在于土壤微孔隙中 ;而适于生活在土壤疏松大孔隙中的真菌数量极少。应注意土壤结构的改良 ,为丰富土壤微生物提供良好的生态环境 相似文献
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天津半干旱地区不同种植年限菜田土壤微生物变化特征的研究 总被引:3,自引:0,他引:3
对天津周边半干旱地区不同种植年限的菜田土壤微生物状况调查研究表明 ,该地区土壤微生物以细菌为主 ,夏季微生物总量大大高于冬季 ;随着种菜年限的增加 ,耕层和亚耕层微生物总量都有增加趋势 ,其中细菌和放线菌增加明显 ,真菌有下降趋势 ;真菌类群分析表明 ,少数纤维素分解菌 ,如青霉 (Penicillium)、木霉 (Trichoderma)等为优势菌 ,而糖和木质素分解菌仅占少数。用尖孢镰刀霉 (Fusariumuoxysporum)、大肠杆菌 (Escherichia coli)接种不同种菜年限土壤 ,检测土壤拮抗菌状况发现 ,拮抗菌仅在种植年限长的老菜田的放线菌中发现。表明北方半干旱地区菜田土壤细菌为优势菌 ,主要存在于土壤微孔隙中 ;而适于生活在土壤疏松大孔隙中的真菌数量极少。应注意土壤结构的改良 ,为丰富土壤微生物提供良好的生态环境 相似文献
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Phytoremediation is an emerging technology based on the use of green plants to remove, contain, inactivate or destroy harmful
environmental pollutants. Recent developments in Europe and the USA show that the approach is somewhat different on both sides
of the Atlantic. In Europe, phytoremediation has more basically been research driven and, based on the outcomes, applications
have been envisaged. By contrast, the approach in the USA is more application and experience driven. In spite of a growing
track record of commercial success, more demonstration projects are needed to prove that phytoremediation is effective in
order to rigorously measure its underlying economics, and to expand its applications. More fundamental research is also required
to better understand the complex interactions between pollutants, soil, plant roots and micro-organisms at the rhizosphere
level, to increase the bioavailability of pollutants, to fully exploit the metabolic diversity of plants and, thus, to successfully
implement this new green technology. 相似文献
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Water, Air, & Soil Pollution - Epiphytic lichens were sampled in a Dutch national monitoring survey, which was carried out twice within 5 yr. The samples were analyzed by neutron activation... 相似文献
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Howard B. Ross 《Water, air, and soil pollution》1987,36(3-4):349-363
Trace metals (Cd, Cu, Fe, Mn, Pb, and Zn) concentrations in atmospheric precipitation have been routinely monitored in Sweden since the autumn of 1983. Concentrations are highest in southern Sweden and decrease northward. It is postulated that the long range transport of anthropogenic pollutants from the rest of Europe is the major source of Cd, Pb, and Zn in precipitation. Evidence for this hypothesis is that enrichment factors indicate anthropogenic origin, and Swedish atmospheric emissions of Zn and Cd are 2 to 3 times smaller than deposition fluxes. Also, Cd, Pb, and Zn concentrations are correlated in both space and time and are also well correlated with exSO4 +, a substance known to be of anthropogenic origin transported long distances. 相似文献
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不同种植模式下菜地土壤腐殖质组分特性的动态变化 总被引:12,自引:0,他引:12
通过在南京普朗克有机农场开展的9年长期定位监测,研究了有机(露地和大棚)和常规种植模式下蔬菜地耕层土壤有机碳和土壤腐殖质组分特性的动态变化。结果表明,有机露地、有机大棚和常规露地种植土壤有机碳含量分别从11.41、9.29、9.00 g k g-1提高至15.35、20.90、10.00 g kg-1;胡敏酸碳(CHA)分别从1.79、1.23、1.14 g kg-1提高至2.11、3.11、1.31 g kg-1;富里酸碳(CFA)分别从2.19、1.88、1.73 g kg-1提高至2.44、2.68、1.91 g kg-1。两种有机种植模式的土壤有机碳及腐殖质组分含量增加达到显著水平,而常规种植模式下的变化不显著。两种有机种植模式下表征土壤腐殖质品质的胡/富比(CHA/CFA)、胡敏酸占总腐殖物质的比例(PQ值)均高于常规种植模式,土壤富里酸的E4/E6值、色调系数(ΔlogK)值随着种植时间增加的幅度较常规种植模式更大,土壤胡敏酸芳化度呈现先降低后增高的趋势,但在常规种植下变化不明显。说明土壤在长期有机种植模式下不仅更有利于土壤有机碳的积累,而且能促进土壤腐殖化进程。 相似文献
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Jenny Sundberg Per-Erik Karlsson Linda Schenk Hâkan Pleijel 《Water, air, and soil pollution》2006,173(1-4):339-354
Ozone (O3) concentration and air temperature/relative humidity were monitored using diffusive samplers (weekly, 3 m above ground) and Tinytag loggers (10 min sampling, 1 m above ground, self-ventilating radiation shields), respectively, in the forested landscape of south-west Sweden, 40 km north-east of Gothenburg. Two forest sites were included, one at a hilltop (175 m a.s.l.), and one in a nearby (~1 km) valley (110 m a.s.l.). In addition, a valley site (~3 km from the forest sites, 60 m a.s.l.) in an agricultural landscape was included, where ozone was measured using both a UV-based monitor and diffusive sampling. At the agricultural site measurements of temperature and relative humidity were made using a radiation shield with forced ventilation and with Tinytags, as on the forest sites, in addition to observations of wind speed and the vertical temperature gradient. Furthermore, comparison with O3 concentrations at urban and coastal sites in the region was made. The temperature dependent, systematic error of using a self-ventilating radiation shield was estimated and corrected for. It was found that the elevated forested site experienced higher O3 concentrations and lower evening cooling rates in calm situations as compared to the forest site in the valley and in particular as compared to the agricultural site. This can be explained by a stronger coupling with the planetary boundary layer at the elevated site and more pronounced night-inversions at the valley sites. The difference in weekly O3 concentration between the two forested sites was correlated with the difference in average minimum night-time temperature. The coastal site had the highest ozone concentrations, related largely, but not fully, to higher night-time O3 concentrations. The urban site showed a depression in O3 concentration associated with the combination of large NO emissions and slow air mixing during the morning traffic rush hours. 相似文献