海委布置2013年度海河流域全国水土流失动态监测与公告项目

2013年3月9—10日,海河流域水土保持监测中心站在天津市布置了2013年度海河流域全国水土流失动态监测与公告项目。
　　会议介绍了2013年度全国水土流失动态监测与公告项目中海河流域的主要工作任务,明确了海河流域要对国家级水土流失重点治理区(永定河重点治理区、太行山重点治理区)、国家级水土流失重点预防区(滦河重点预防保护区)、不同土壤侵蚀类型区(5个典型小流域、8个典型监测点)的水土流失情况进行监测,对流域监测网络和信息系统进行运行维护,为年度中国水土保持公报编制提供海河流域水土流失监测数据。     

河北省太行山小流域经济开发模式研究

对太行山区重点治理小流域进行了深入调查研究 ,根据岩性、地理位置和地形条件 ,将太行山区小流域划分为 4种类型 ,即西部深山区片麻岩小流域、东部浅山区片麻岩小流域、地形坡度较陡的石灰岩小流域、地形坡度较缓的石灰岩小流域。通过运用多元线性回归和灰色预测方法对各类型小流域的土地利用结构、产业结构和投资结构进行分析 ,得出了太行山不同类型区的小流域经济开发优化模式     

因地制宜地发展聚流型农业──以党家水流域为例谈干旱草原区小流域综合治理的方式与途径

干旱草原类型区在我国北部黄土高原地区占有相当大的面积，其主要特点是干旱，风沙，水土流失，地广人稀。如何在这类地区开展以小流域为单元的水土保持综合治理工作，促使群众早日脱贫致富，是一项十分迫切的任务，但以往还没有一个较成熟的办法。党家小水流域经过５年的水土保持综合治理试点，根据本区的特点，因地制宜和科学地用洪用沙，发展聚流型农业，取得十分显的效果，为干旱草原类型区开展小流域水土保持综合治理提供了新     

蚂蚁河流域水土流失与水土保持生态建设

蚂蚁河流域是黑龙江省水土流失较为严重的区域，在综合调查的基础上，分析了流域水土流失类型、成因、危害,对水土流失类型区进行了划分，确定了流域水土保持生态建设任务和具体措施，并进行了效益分析。     

河北省太行山区小流域综合治理模式研究

划分了河北省太行山区小流域类型及其立地类型,通过对不同类型区相同立地条件下不同治理模式的经济,生态效益分析比较,提出了一套适合河北省太行山片麻岩区,石灰岩区小流域的综合治理模式。     

太行山低山丘陵区小气候条件与人工植被建设

为开发太行山低山丘陵区气候资源、营建高效生物群落，本文通过对大量野外定点小气候试验观测资料的分析，提示了该类型区小气候要素梯度分布规律，确定了低山丘陵区代表地形不同坡位的气候植被类型，进而分析了低山丘陵区人工植被建设的小气候适宜度。     

正宁县移风沟流域经济类型区划及发展方向分析

<正> 移风沟流域是黄河中游局在黄土高原沟壑区选择的第四批水土保持综合治理、开发、科学试验、示范的试点流域。总体来看,流域内有着较好的大农业基础,但是村与村之间的发展很不平衡,为了对全流域经济进行系统研究和宏观调控,便于分类指导,使不同类型区的经济都能稳步发展,我们采用了系统聚类的方法财流域的六个行政村进行了经济类型区的划分,并提出了今后各区的发展方向。     

宁夏南部山区流域分类及其综合治理模式

以宁南山区固原市原州区、彭阳县、隆德县的48个典型小流域作为研究对象，选取小流域内沟壑密度、人均耕地、立地类型（耕地、林地、牧草地）等作为指标，对研究区48个小流域进行聚类分析分为4个类型，即：低人口密度流域类型、中高人口密度流域类型、中人口密度流域类型Ⅰ、中人口密度流域类型Ⅱ。在此分类的基础上提出了各类型区综合治理模式。     

关于晋江流域水土流失类型区划分的探讨

晋江流域水土流失类型分区争议颇多，本在对当地实际情况充分调查的基础上，以突出区域地貌、土地开发利用、水土流失类型程度等特征的命名方式进行各类型区的划分，并提出针对性的防治策略。     

石窟小流域水土保持措施及效益分析

石窟小流域位于潞城市西北部店上镇,流域总面积4 026 hm^2,其中水土流失面积3 521 hm^2,占总面积87.46%。2016年该流域被列为国家太行山水土保持重点建设工程区,经过短期强化治理,水土保持程度大大提高。在分析当地自然环境、社会经济、水土流失与水土保持情况的基础上,根据当地农村经济发展形势和生态建设需要,确定了水土保持思路,制定了实施方案,分析了重点治理实施后的综合效益。     

Accumulation of copper in soils and leaves of tomato plants in greenhouses in Turkey

Copper (Cu)‐containing fertilizers, fungicides, and bactericides has been used extensively in the greenhouses in the Antalya province in recent decades with the use of such materials tending to increase year by year. The level of DTPA‐extractable Cu was determined in 210 soils (0–20 and 20–40 cm depth) and 105 leaf samples obtained from 105 tomato greenhouses. The DTPA‐extractable Cu contents of the soils taken from the 0–20 depth ranged between 0.76 and 88.03 mg kg^‐1 (mean 7.79 mg kg^‐1). The percentage of soils containing DTPA‐extractable Cu greater than the critical toxicity level (20 mg kg^‐1) was 8.1. The Cu content of tomato leaf samples ranged between 2.4 and 1,490 mg kg^‐1 (mean 166.5 mg kg^‐1). The Cu concentration in leaf samples was very high due to the intensive use of foliar applied Cu‐containing chemicals. As a consequence, 24.8% of the leaf tomato samples analyzed contained over 200 mg Cu kg^‐1, the maximum accepted tolerance level. Therefore, it may be necessary to reduce the use of Cu‐containing pesticides and fertilizers, or at least reduce the amount of Cu‐containing fertilizers being used in those greenhouses where Cu‐containing pesticides have been or are being used.     

Role of selenium in mitigation of cadmium toxicity in pepper grown in hydroponic condition

Selenium (Se) is an essential element for humans but is not considered as essential for plants. However, its beneficial role in improving plant growth and stress tolerances is well established. In order to study the role of Se in cadmium (Cd) toxicity in pepper (Capsicum frutescens cv. Suryankhi Cluster), this experiment was carried out in greenhouse conditions. Treatments comprised Cd [0, 0.25, and 0.5 mM cadmium chloride (CdCl₂)] and Se [0, 3, and 7 µM sodium selenite (Na₂SeO₃)] with three replications. The result showed that Cd decreased chlorophyll a, chlorophyll b, and carotenoids, whereas Se supplementation diminished Cd toxicity on photosynthetic pigment. Selenium at 7 µM significantly increased the leaf area in the plants grown at 0.25 mM Cd. The application of Se at 3 µM with 0.25 mM Cd and Se at 3 µM and Se at 7 µM with 0.5 mM Cd increased the activity of catalase (CAT). Selenium at 7 µM decreased the proline content of pepper leaves exposed to Cd at 0.5 mM (30%). Selenium significantly enhanced the antioxidant activity of leaves, which was diminished by Cd toxicity. In general, Se has a beneficial effect on plant growth and is an antioxidant enzyme of pepper cv. Suryankhi Cluster under Cd stress and non-stress conditions.     

红壤区不同肥力水稻土根际硝化作用特征

通过根际培养箱(三室)——速冻切片技术研究了红壤地区高、低两种肥力下水稻苗期根表、根际和土体土壤矿质态氮含量和硝化强度,以及水稻生长、氮素积累的差异。结果表明,肥力水平对水稻根表和根际土壤铵态氮(NH4+-N)含量无显著影响,但高肥力显著提高土体土壤NH4+-N含量,以及根表、根际和土体土壤硝态氮(NO3--N)含量及硝化强度。两种肥力水稻土硝化强度最大值均出现在距根表2 mm处,分别为0.20和0.31μmol kg-1 h-1。土体土壤硝化强度随距根表距离增加而降低,低肥力土壤在距根表10～40mm处时硝化强度接近本底值,而高肥力土壤在距根表20～40 mm处时接近本底值。与不种水稻的CK相比,种植水稻显著提高根际土壤硝化强度。高肥力能显著改善水稻生长,增加植株氮素积累量,尤其显著促进根系生长及通气组织发育。由于红壤稻田肥力水平的差异造成水稻根际硝化强度以及水稻吸收NO3-的差异,导致高肥条件下水稻显示出更强的生长势和氮素吸收利用能力。因此,合理提高红壤稻田肥力水平对改善红壤区水稻根际土壤硝化作用及水稻氮素营养具有重要意义。     

自由基在鸡肾病发生中的作用研究

肾病即急性肾小管坏死.鸡肾病在养鸡生产中极为常见,尤其近年来,鸡肾病的发生日益增多,由于其发生机制不清楚,临床治疗鸡肾病的依据不足,致使治疗效果不佳,为此,提出本研究以探讨鸡肾病的发生机制,为本病防治提供理论依据.     

Occurrence of Sexual Hormones in Sediments of Mangrove in Brazil

The presence of sexual hormones (female estrogens) was assessed in sediments of a mangrove located in the urban region of southern Brazil. The estrogens are involved in human sexual reproduction. They act as the chemical messengers, and they are classified as natural and synthetic. The estrogens inputs in the environment are from treated and untreated sewage. The presence of estrogens in sewage is excretion from the female due to natural production and use of contraceptives (synthetic estrogens). With the indiscriminate release of sewage into the environment, estrogens can be found in rivers, lakes, and even in oceans. In this work, the presence of estrone (E1), 17-??-estradiol (E2), and 17-??-ethynilestradiol (EE2) in eight sedimentary stations in Itacorubi mangrove located on Santa Catarina Island, south Brazil, was investigated. Historically, the Itacorubi mangrove has been impacted by anthropogenic activities because the mangrove is inserted in the urban area of the Florianopolis. The estrogen EE2, used as contraceptive, had the highest concentration in mangrove sediment, 129.75?±?3.89 ng/g. E2 was also found, with its concentration ranging from 0.90?±?0.03 to 39.77?±?1.19 ng/g. Following the mechanism, under aerobic or anaerobic conditions, E2 will first be oxidized to E1, which is further oxidized to unknown metabolites and finally to CO₂ and water (mineralized). EE2 is oxidized to unknown metabolites and also finally mineralized. Theoretically, under anaerobic conditions, EE2 can be reduced to E1 even in environments such as mangrove which is essentially anaerobic.     

Meta-analysis in the Selection of Groups in Varieties of Citrus

Brazil is the largest producer of oranges (Citrus sinensis) in the world. The nutrient management of tree orchards is designed from experiments with a limited number of varieties. This knowledge is transferred to other varieties by diagnosing tissue nutrient composition and tree demand. Compositional data analysis has been first applied to tissue analysis of agricultural crops using centered log ratios with compositional nutrient diagnosis (CND-clr). The isometric log ratio (ilr) transformation is a new approach based on binary nutrient ratios and the principle of orthogonality (CND-ilr). We analyzed eleven nutrients: nitrogen (N), sulfur (S), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), boron (B), copper (Cu), zinc (Zn), manganese (Mn), and iron (Fe) in leaf tissue samples across 108 commercial plots (thirty-one grow Valencia, twenty-two Hamlim, twenty Pera, and thirty-five Natal). Nutrients were partitioned between macro- and micronutrients as well as anionic and cationic species. The effect size of varieties over Valencia was quantified by the mean and standard deviation of ilr values across ilr coordinates. Specific varietal nutrient profiles and ilr norms were defined. The nutrient profile of orange varieties could be classified into homogeneous groups to take advantage of fertilizer trials conducted on varieties of the same group. The Aitchison distance and a perturbation vector could be instrumental for diagnostic purposes and nutrient management.     

Effect of iron-quercetin complex on reduction of nitrite in in vitro and in vivo systems

This study investigated whether reducing agents such as quercetin and iron(II) facilitate formation of nitric oxide (NO) gas from orally ingested nitrite in an vivo study. When 3 mg/kg Na (15)NO2 was orally administered to rats with or without iron(II) or quercetin, Hb (15)NO, which is indicative of systemic (15)NO, was detected in the blood, with the maximum blood concentration of Hb (15)NO at 15 min after nitrite or nitrite plus quercetin treatment, whereas after administration of nitrite plus iron(II) or nitrite plus iron(II) and quercetin, the time was shortened to 10 min. Interestingly, iron(II), quercetin, or iron(II) plus quercetin did not affect the total amount of Hb (15)NO generated from orally administered Na (15)NO2. However, the systemic nitrite concentration was significantly decreased in the presence of iron(II) or iron(II) plus quercetin. These results may indicate that iron(II) is critical to the generation of NO gas from nitrite, whereas quercetin contributed little under the in vivo experimental conditions.     

旱地果园水肥管理模式研究进展

分析了旱地果园水肥管理模式的研究进展和存在问题,指出水肥胁迫尤其是水钾已成为旱区果树高产稳产优质化的主要限制因子。在系统探讨旱地果园水分管理、养分管理、综合管理以及果树叶营养综合诊断施肥标准的基础上,提出了旱地果园的高效水肥管理模式。     

Role of aldehyde oxidase in the hepatic in vitro metabolism of 3-methylindole in pigs

The metabolism of 3-hydroxy-3-methylindolenine (HMI), a recently discovered metabolite of 3-methylindole (3MI, skatole) produced by porcine liver microsomes, was investigated in vitro using porcine liver cytosol. HMI was rapidly metabolized to a single product, 3-hydroxy-3-methyloxindole (HMOI), by porcine cytosol. By the use of the selective inhibitors menadione and quinacrine, it was shown that the enzyme responsible for the oxidation of HMI into HMOI was aldehyde oxidase (AO; aldehyde:oxygen oxidoreductase, EC 1.2.3.1). The activity of AO in the conversion of HMI to HMOI was measured in a population of pigs (n = 30) with a wide range of 3MI levels in back fat (0.07-0.30 mg/kg). AO activity was found to be negatively correlated (r = -0.70; P < 0.001) with the level of 3MI in fat. The results of the present study suggest that AO plays an important role in the metabolism of 3MI in the pig and that its catalytic activity is related to an adequate 3MI clearance.     

东北黑土土壤磷的纬向分异

以中国东北的中纬度黑土区为样带,研究了有机磷浓度与有机质、全氮浓度的关系;全磷、有机磷、无机磷及有机磷和无机磷的比率与纬度分布的关系。结果表明,有机磷和有机质、全氮浓度具有良好的相关性,它们之间的相关系数分别为0.90和0.92,呈极显著正相关(P<0.01)。全磷、有机磷、无机磷、P_o/P_i在纬度上都存在不同程度的分异规律,即随着纬度的升高,其浓度或比率均有逐渐升高的趋势;其相关系数分别为0.68、0.77、0.26和0.60,相关分析表明,这些纬向分异规律都达极显著水平(P<0.01)。除了无机磷的纬向分异原因尚不明确之外,其他纬向分异的原因可能是由于黑土南北样带气候热量上的差异和人类活动的影响所致,从而造成南北样带之间有机质的矿化程度和速率产生差异。