Constructing Universities as Organizations: University Reforms in Poland in the Light of Institutional Theory

This chapter shows that apart from changes at the systemic and institutional levels, successful reform implementation struggles with a gradual change in academic beliefs, attitudes and behaviours. Currently, visions of the university proposed by the Polish academic community and visions of it proposed by Polish reformers and policymakers (within ongoing reforms) are worlds apart. I shall study recent reforms in the context of specific academic self--protective narratives being produced in the last two decades (at the collective level of the academic profession) and in the context of the Ivory Tower university ideals predominant at the individual level (as studied comparatively through a large--scale European survey of the academic profession). Institutions change both swiftly, radically – and slowly, gradually. Research literature on institutional change until recently was focused almost exclusively on the role of radical changes caused by external shocks, leading to radical institutional reconfigurations. And research literature about the gradual, incremental institutional change have been emergent for about a decade and a half now (Mahoney and Thelen 2010; Streeck and Thelen 2005, 2009; Thelen 2003). Polish higher education provides interesting empirical grounds to test institutional theories. Both types of transformations (radical and gradual) may lead to equally permanent changes in the functioning of institutions, equally deep transformations of their fundamental rules, norms and operating procedures. Questions about institutional change are questions about characteristics of institutions undergoing changes. Endogenous institutional change is as important as exogenous change (Mahoney and Thelen 2010: 3). Moments in which there emerge opportunities of performing deep institutional reforms are short (in Poland these moments occurred in 2009-2012), and between them there are long periods of institutional stasis and stability (Pierson 2004: 134-135). The premises of theories of institutional change can be applied systematically to a system of higher education which shows an unprecedented rate of change and which is exposed to broad, fundamental reform programmes. There are many ways to discuss the Kudrycka reforms - and "constructing Polish universities as organizations" (rather than traditional academic "institutions") is one of more promising. In this account, Polish universities are under construction as organizations, and under siege as institutions. They are being rationalized as organizations, following instrumental rather than institutional logics. Polish academics in their views and attitudes are still following an institutional logic, while Polish reforms are following the new (New Public Management-led) instrumental logics. Both are on a collision course about basic values. Reforms and reformees seem to be worlds apart. I am discussing the the two contrasting visions of the university and describing the Kudrycka reforms as the reistitutionalization of the research mission of Polish universities. The core of reforms is a new level of funding and governance - the intermediary one (and no longer the state one), with four new peer-run institutions, with the KEJN, PKA and NCN in the lead. Poland has been beginning to follow the "global rules of the academic game" since 2009. I am also discussing two academic self-protection modes agains reforms: (Polish) "national academic traditions" and "institutional exceptionalism" (of Polish HE). Both discourses prevailed for two decades, none seems socially (and politically) acceptable any more. Old myths do not seem to fit new realities. In this context I am discussing briefly and through large-scale empirical data the low connectedness to the outside world of Polish HE institutions, low influence of the government on HE policies and the low level of academic entrepreneurialism, as seen through the EUROAC/CAP micro-level data. The conclusion is that the Kudrycka reforms are an imporant first step only - Poland is too slow in reforms, and reforms are both underfunded and inconsistent. Poland is still accumulating disadvantages as public funding and university reforms have not reached a critical point. Ever more efforts lead to ever less results, as macro-level data show. Consequently, it may be useful to construct universities as organizations in Poland to a higher degree than elsewhere in Europe, and especially in Western Europe.

Dinámicas entre tensiones espaciales como instituciones sobre la propiedad de la tierra en la ley de reparación de víctimas y restitución de tierras: evolución histórica y situación actual.

Antes de que Colombia fuera país, ya existían disputas, enfrentamientos e injusticias en torno a la estructura de acceso, tenencia y usufructo de la tierra. Tal situación engendró tensiones espaciales, que se pueden abordar y caracterizar a partir de un marco teórico sobre neoinstitucionalismo político. Con lo anterior en mente, el objetivo de ésta investigación , fue el de determinar la manera en que las dinámicas entre tensiones espaciales históricas como instituciones, delinearon el contexto del cual surgió la Ley 1448 de 2011 (Restitución de tierras y reparación de víctimas del conflicto armado) y la intervención e incidencia que ésta pretende, en la coyuntura actual.

Caracterización del comportamiento emprendedor de los estudiantes de jurisprudencia de la Universidad del Rosario

Hoy en día, el emprendimiento se ha convertido en uno de los factores esenciales para promover el desarrollo y fomentar la evolución de la sociedad a nivel mundial. Enfocándonos en Colombia y más específicamente en una población delimitada, el centro de emprendimiento de la Universidad del Rosario desarrolló un estudio que permitiera medir la caracterización del perfil emprendedor de sus estudiantes, éste con el objetivo de identificar diferentes variables que inciden en el entorno de los estudiantes al momento de edificar su perfil emprendedor. Por lo anterior, esta investigación se centró en realizar un análisis de la caracterización del comportamiento del perfil emprendedor de los estudiantes de Pregrado de la Facultad de Jurisprudencia de la Universidad del Rosario, la cual permitió comprender un perfil mucho más detallado a la luz de variables identificables. Para su desarrollo, se utilizó la herramienta homologada a nivel internacional conocida como "Características del Comportamiento Emprendedor" o CCE de EMPRETEC basándose en la teoría de McClelland donde se observaron los factores motivacionales que se asocian directamente al comportamiento emprendedor. La metodología usada permitió caracterizar el comportamiento de los estudiantes de la facultad de Jurisprudencia de 1° a 10° semestre mediante la evaluación de 10 factores asociados a necesidades de logro, poder y afiliación.

东北地区不同纬度梯度农田土壤Olsen-P���分布特征

本文研究了中国东北地区不同纬度梯度农田土壤Olsen-P���0～100cm剖面中的分布特征。结果表明,除公主岭和大石桥外,其他各点土壤Olsen-P���量在0～20cm土层较高,20～40cm土层迅速下降,40～100cm各土层又逐渐升高,但底层要远低于表层。不同纬度梯度下各点0～20cm土层Olsen-P���量为暗棕壤>黑土>棕壤,高纬度地点Olsen-P���量具有高于低纬度地点的趋势;20～100cm各土层Olsen-P���量总体表现为黑土和暗棕壤相对较高,棕壤区偏低,没有明显的纬度分异现象。施肥等农田管理措施对0～20cm土壤Olsen-P���量有明显影响,其他土层Olsen-P���量可能主要受磷素运移特点和成土母质等因素影响。

Fósforo adsorbido : su relación con el P Bray y Olsen en grandes grupos de suelos de la Provincia de Buenos Aires

p.253-262

Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization

The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ∼8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD.

Aging, retirement, and changes in physical activity : prospective cohort findings from the globe study

There is increased recognition that determinants of health should be investigated in a life-course perspective. Retirement is a major transition in the life course and offers opportunities for changes in physical activity that may improve health in the aging population. The authors examined the effect of retirement on changes in physical activity in the GLOBE Study, a prospective cohort study known by the Dutch acronym for "Health and Living Conditions of the Population of Eindhoven and surroundings," 1991–2004. They followed respondents (n = 971) by postal questionnaire who were employed and aged 40–65 years in 1991 for 13 years, after which they were still employed (n = 287) or had retired (n = 684). Physical activity included 1) work-related transportation, 2) sports participation, and 3) nonsports leisure-time physical activity. Multinomial logistic regression analyses indicated that retirement was associated with a significantly higher odds for a decline in physical activity from work-related transportation (odds ratio (OR) = 3.03, 95% confidence interval (CI): 1.97, 4.65), adjusted for sex, age, marital status, chronic diseases, and education, compared with remaining employed. Retirement was not associated with an increase in sports participation (OR = 1.12, 95% CI: 0.71, 1.75) or nonsports leisure-time physical activity (OR = 0.80, 95% CI: 0.54, 1.19). In conclusion, retirement introduces a reduction in physical activity from work-related transportation that is not compensated for by an increase in sports participation or an increase in nonsports leisure-time physical activity.

Why do poor people perceive poor neighbourhoods? : the role of objective neighbourhood features and psychosocial factors

Compared to people with a high socioeconomic status, those with a lower socioeconomic status are more likely to perceive their neighbourhood as unattractive and unsafe, which is associated with their lower levels of physical activity. Agreement between objective and perceived environmental factors is often found to be moderate or low, so it is questionable to what extent ‘creating supportive neighbourhoods’ would change neighbourhood perceptions. This study among residents (N=814) of fourteen neighbourhoods in the city of Eindhoven (the Netherlands), investigated to what extent socioeconomic differences in perceived neighbourhood safety and perceived neighbourhood attractiveness can be explained by five domains of objective neighbourhood features (i.e. design, traffic safety, social safety, aesthetics, and destinations), and to what extent other factors may play a role. Unfavourable neighbourhood perceptions of low socioeconomic groups partly reflected their actual less aesthetic and less safe neighbourhoods, and partly their perceptions of low social neighbourhood cohesion and adverse psychosocial circumstances.

Socioeconomic inequalities in cardiovascular mortality and the role of childhood socioeconomic conditions and adulthood risk factors : a prospective cohort study with 17-years of follow up

Background The mechanisms underlying socioeconomic inequalities in mortality from cardiovascular diseases (CVD) are largely unknown. We studied the contribution of childhood socioeconomic conditions and adulthood risk factors to inequalities in CVD mortality in adulthood. Methods The prospective GLOBE study was carried out in the Netherlands, with baseline data from 1991, and linked with the cause of death register in 2007. At baseline, participants reported on adulthood socioeconomic position (SEP) (own educational level), childhood socioeconomic conditions (occupational level of respondent’s father), and a broad range of adulthood risk factors (health behaviours, material circumstances, psychosocial factors). This present study is based on 5,395 men and 6,306 women, and the data were analysed using Cox regression models and hazard ratios (HR). Results A low adulthood SEP was associated with increased CVD mortality for men (HR 1.84; 95% CI: 1.41-2.39) and women (HR 1.80; 95%CI: 1.04-3.10). Those with poorer childhood socioeconomic conditions were more likely to die from CVD in adulthood, but this reached statistical significance only among men with the poorest childhood socioeconomic circumstances. About half of the investigated adulthood risk factors showed significant associations with CVD mortality among both men and women, namely renting a house, experiencing financial problems, smoking, physical activity and marital status. Alcohol consumption and BMI showed a U-shaped relationship with CVD mortality among women, with the risk being significantly greater for both abstainers and heavy drinkers, and among women who were underweight or obese. Among men, being single or divorced and using sleep/anxiety drugs increased the risk of CVD mortality. In explanatory models, the largest contributor to adulthood CVD inequalities were material conditions for men (42%; 95% CI: −73 to −20) and behavioural factors for women (55%; 95% CI: -191 to −28). Simultaneous adjustment for adulthood risk factors and childhood socioeconomic conditions attenuated the HR for the lowest adulthood SEP to 1.34 (95% CI: 0.99-1.82) for men and 1.19 (95% CI: 0.65-2.15) for women. Conclusions Adulthood material, behavioural and psychosocial factors played a major role in the explanation of adulthood SEP inequalities in CVD mortality. Childhood socioeconomic circumstances made a modest contribution, mainly via their association with adulthood risk factors. Policies and interventions to reduce health inequalities are likely to be most effective when considering the influence of socioeconomic circumstances across the entire life course and in particular, poor material conditions and unhealthy behaviours in adulthood.

黄土高原沟壑区不同年限苹果园土壤碳、氮、磷变化特征

管理措施是影响土壤质量演变的重要因素。分析和讨论了5、101、5年苹果园耕层(0—20 cm)和0—200 cm土壤有机碳、全氮、全磷、有效磷和硝态氮含量及其影响因素。结果表明,5年、10年和15年的塬面苹果园表层土壤有机碳依次为7.5、6.7和6.7 g/kg;全氮依次为0.940、.85和0.83 g/kg;但土壤全磷和速效磷含量随着种植年限而增加,与5年苹果园相比,塬面10年苹果园土壤全磷、速效磷含量分别提高了11%、60%,并且磷素的变异性随年限而增加。坡地10年、15年和20年苹果园土壤有机碳依次为6.36、.2和6.5 g/kg,全氮依次为0.76、0.76和0.81 g/kg;与10年苹果园相比,15年苹果园土壤全磷、速效磷含量分别提高了20%、28%。土壤剖面0—80 cm内不同土地利用方式土壤碳、氮、磷含量随土层加深而降低,80 cm以下不同利用条件苹果园土壤碳、磷含量差异不大,氮素含量在100 cm土层下随苹果园种植年限增加而增加。

活化剂对黑土磷有效性及玉米产量影响研究

磷肥低利用率造成了经济损失，给人们赖以生存的环境造成了不良后果，因而提高磷肥利用率意义重大。温度对植物磷营养及土壤磷有效性影响较大，然而探索不同温度下磷活化剂的效应（特别是对磷组成的影响）少有研究。本文以腐植酸（HA）、柠檬酸铵、活化剂H2为供试磷素活化剂，以吉林黑土为供试土壤，研究活化剂对土壤磷有效性及玉米产量的影响。 ①培养试验表明：自然不施磷水平下，在一定温度范围内，高温更有利于Olsen-P���量增加。施入磷肥后，情况相反，特别是培养前期，高温加速磷的固定。活化剂能有效提高土壤Olsen-P���，10℃和20℃时活化效果较好，主要通过增加Ca2-P���Ca8-P���Al-P���量来实现。10℃时三种活化剂活化能力为柠檬酸铵＞HA＞活化剂H2，分别提高土壤Olsen-P���达40.9%、33.1%、23.2%；20℃时活化能力为HA＞柠檬酸铵＞活化剂H2，分别提高32.4%、24.9%、16.7%；30℃时无明显增效。活化剂对无机磷总量无明显增效。通过相关分析、通径分析和回归分析证实，Al-P���Ca2-P���黑土有效磷的主要组分，与Olsen-P���极显著的相关性，其它形态的磷可以通过影响Al-P���Ca2-P���含量间接作用于Olsen-P��� ②大田试验表明：苗期-抽穗期-腊熟期各处理土壤有效磷含量都呈下降趋势，特别是苗期-抽穗期，有效磷含量急剧降低，下降幅度为47.1%~50.2%，活化剂处理都一定程度地减缓了有效磷下降的趋势。活化剂不同幅度的增大了玉米产量，以H2（450kg/hm2）产量为最，比对照增产9.32%，其次为柠檬酸铵（15kg/ hm2）和HA（150kg/ hm2），分别增产5.99%和4.99%。玉米产量与抽穗期土壤有效磷的相关性相对较大。活化剂处理对玉米产量的提高主要是通过增加千粒重来实现的。

长期施肥对潮棕壤无机磷组分的影响

本研究在潮棕壤上进行长期施肥试验(开始于1990年)，涵盖了中国颇具代表性的8种施肥模式：不施肥(CK)、单施循环猪圈肥(M)、单施氮肥(N)、氮肥+循环猪圈肥(N+M)、氮肥+磷肥(NP)、氮肥+磷肥+循环猪圈肥(NP+M)、氮肥+磷肥+钾肥(NPK)、氮肥+磷肥+钾肥+循环猪圈肥(NPK+M)。 对1990年本底和2004年耕层(0~20cm)土壤样品以及1995年、2001年和2007年耕层(0~20cm)土壤样品进行无机磷分级测定。纵观这18年施肥处理，结果表明：有效或缓效态无机磷(Ca2-P���Ca8-P���Al-P���Fe-P)在无磷肥直接投入的情况下皆有不同幅度的下降，导致土壤无机磷收支赤字，在有磷肥直接投入的情况下，这些形态的无机磷不但能满足当季作物需求还有盈余，丰富了土壤P���；而O-P���Ca10-P���两种形态的无机磷的生物有效性很低，但可由盈余的有效态无机磷缓慢转化而来，长期试验结果表明，盈余有效态无机磷会逐渐转变成无效态，肥效降低；所有的施加循环猪圈肥的处理相对于单施化肥的处理能减缓无机磷素的下降，促进磷素缓慢积累，甚至能逐步建立起小规模的P���，可见循环猪圈肥不但能发挥前期供磷作用，也有较好的后期供磷作用。 各形态无机磷与速效P(Olsen-P)之间存在很好的相关性，对土壤中各形态无机磷与速效进行通径分析及逐步回归分析，在全部引入各因子的情况下得出回归方程：Y=15.127+2.158x1+0.152x2+0.265x3+0.168x4-0.128x5-0.247x6 (R2=0.9997，F=571.78，Pr=0.032；Y、x1、x2、x3、x4、x5和x6分别代表Olsen-P���Ca2-P���Ca8-P���Al-P���Fe-P���O-P���Ca10-P���含量)，这进一步明确了各因子间的关系。无机磷分级与速效含量测定相结合，可以为评价土壤供磷力提供更科学的理论依据。 循环猪圈肥(M)对土壤无机磷形态的影响与矿质磷肥截然不同，对几种有机物料(大豆秸秆粉、玉米秸秆粉、新鲜猪粪和腐熟猪粪)进行无机磷分级测定，研究发现：秸秆粉中各形态无机磷的含量甚微，而新鲜猪粪中含量较高，各种有机物料中Ca2-P���Ca8-P���Al-P���含量明显高于其它组分，新鲜猪粪与秸秆粉混合堆腐，其Ca2-P���Ca8-P���量有所下降，腐熟猪粪中有效态的无机磷组分主要来自新鲜猪粪。循环猪圈肥(M)在施入土壤初期，会提供大量的Ca2-P���Ca8-P���这两部分主要来自新鲜猪粪，并且随着土壤微生物的活动，循环猪圈肥(M)将再次缓慢释放出Ca2-P���Ca8-P���发挥后效作用；循环猪圈肥(M)在施入土壤初期还能提供相当数量的Al-P���Fe-P���O-P���但是，与Ca2-P���Ca8-P���同的是，这三种形态无机磷后期释放较少。 为进一步明确土壤无机磷形态变化除了受施肥影响之外有无其它干扰，对三种茬口(一季玉米茬、大豆茬、连作玉米茬)的无机磷分级与速效P���行相关性分析，发现，一季玉米茬、大豆茬口中二者都表现出良好的相关性，而连作玉米茬口中二者相关性弱于前两者，可以说明不同的茬口对于无机磷组分含量影响是不同的。大豆根茬分解释放出的有效态无机磷素成为翌年植物生长一个重要的速效P���。这为合理地评价土壤供磷力、指导磷肥管理提供了科学的理论依据。 本研究选择8种典型的施肥模式来模拟我国农田土壤供磷力的发展。在早期单施有机肥的条件下，循环猪圈肥(M)能释放部分磷素以供作物生长所需，随着施肥年限的增加，其在土壤中残效累积，能建立起小规模的无机P���，在农业发展中对于提高土壤供磷力极为重要；氮肥的施用，加速了作物对磷素的吸收，使得磷素输出加剧，磷素利用率提高，充分利用土壤磷素，间接地提高土壤供磷力，但是土壤P���仍是入不敷出；氮肥配施循环猪圈肥(N+M)，尽管有循环猪圈肥的投入，还是很难满足作物对磷素的需求，土壤供磷力相对低下；磷肥开始施用以后，大大改善了土壤的供磷状况，每年土壤中残存的各无机磷组分有部分盈余，土壤P���逐步扩大，土壤供磷水平大大提高；钾肥的引入，农田土壤供磷水平开始出现转折，因为钾肥能促进磷素的吸收，使得磷素被大量带出农田系统，作物体内磷素含量数据也证明了这一点。

辽东山区次生林生态系统主要林型土壤磷素特征

磷是植物生长发育所必需的营养元素之一，由于磷在土壤中的难溶性和难移动性，使得磷在陆地生态系统的循环越来越受到重视，尤其是在明确土壤磷素存在形态和分布特征的基础上，探讨土壤磷素与土地利用方式以及植被生长发育状况之间的关系，对于指导土地利用和恢复植被建设具有重要意义。本研究以辽东山区天然次生林主要林型胡桃楸林、杂木林（由蒙古栎、花曲柳和山杨等树种组成）和蒙古栎林为主要研究对象，系统研究了辽东山区天然次生林土壤磷素的分布特征，并比较研究了落叶松人工林取代天然次生林后土壤磷素的变化特征。主要结论如下： 1. 辽东山区天然次生林土壤磷素特征：（1）次生林0-30 cm土壤全磷含量的变化范围为326.5 mg kg-1-984.9 mg kg-1，土壤总有机磷含量、总无机磷含量、Olsen-P���量和土壤微生物量磷含量占全磷含量的比例变化范围分别为47%-76%、24%-53%、1.23%-1.40%和2.67%-3.45%，土壤全磷与土壤有机碳、全氮之间呈显著正相关，说明次生林土壤有机质含量是影响土壤磷素含量的主要因素之一；土壤Olsen-P���微生物量磷季节变化明显，均表现为夏季最高，且土壤Olsen-P���微生物量磷的季节变化规律不受植被类型的影响；另外，土壤Olsen-P���土壤微生物量磷的季节变化均与土壤含水量相关。（2）三个林型土壤酸性磷酸酶与土壤有机碳、全氮、全磷、Olsen-P���微生物量磷之间存在密切的相关性，酸性磷酸酶可以作为评价次生林土壤磷素状况的一个指标。（3）不同林型土壤各形态无机磷分布不同，胡桃楸林以Fe-P���铁结合的磷酸盐）和Ca-P���钙结合的磷酸盐）为主，杂木林和蒙古栎林以O-P���闭蓄态磷）为主；不同林型土壤各形态无机磷随季节的变化规律不同，与Olsen-P���关系也不同，胡桃楸林土壤Olsen-P���Al-P���铝结合的磷酸盐）之间具有显著的相关性，杂木林土壤Olsen-P���Fe-P���Ca-P���间相关性显著，蒙古栎林土壤Olsen-P���Ca-P���间显著相关，说明辽东山区不同林型土壤磷素的有效来源不同。（4）辽东山区有机磷各形态的分布特征为：中等活性有机磷 > 中等稳定性有机磷 > 高稳定性有机磷 > 活性有机磷；土壤活性有机磷的季节变化与Olsen-P���化一致，中等活性有机磷、中等稳定性有机磷和高等稳定性有机磷的含量随季节变化无此规律；胡桃楸林、蒙古栎林土壤Olsen-P���活性有机磷、中等稳定性有机磷和高等稳定性有机磷之间显著相关，杂木林土壤Olsen-P���活性有机磷、中等活性有机磷、中等稳定性有机磷和高等稳定性有机磷之间相关性显著，说明在本研究区土壤有机磷对磷素有效性的贡献较大。（5）三个林型内主要树种叶片磷含量均较高，且叶片N/P < 10，土壤磷素不是辽东山区次生林植被生长的限制性养分因子。 2. 落叶松人工林取代天然次生林后土壤磷素特征的变化：（1）和天然次生林相比，落叶松人工林土壤全磷、总有机磷、Olsen-P���土壤微生物量磷和磷酸酶活性均显著降低（P<0.05），土壤总无机磷含量无明显变化，这说明次生林转变为落叶松人工林后土壤磷素状况下降。（2）随着次生林转变为落叶松人工林和落叶松人工林连栽后，土壤无机磷各形态含量变化显著，土壤Fe-P���Ca-P���量逐渐降低，O-P���量升高，土壤Olsen-P���无机磷形态中的Fe-P���Ca-P���间显著正相关，表明了Fe-P���Ca-P���Olsen-P���主要无机磷来源。（3）落叶松人工林取代次生林后，土壤活性有机磷、中等活性有机磷、中等稳定性有机磷和高等稳定性有机磷含量均降低，土壤Olsen-P���活性有机磷显著正相关，活性有机磷是补充Olsen-P���直接有机磷源；土壤微生物量磷与各有机磷组分及 Olsen-P���量之间均呈显著正相关，这说明微生物量磷在有机磷转化中起着重要作用。

不同土壤磷流失过程模拟研究

本研究通过室内培养、淋溶模拟和径流模拟试验，分别对酸性土壤（红壤）和不同质地碱性土壤（潮褐土和黑钙土）磷流失过程进行模拟研究。结果表明，不同土壤相同水分条件下，土壤磷流失潜能不同：潮褐土磷流失潜能最强，黑钙土次之，红壤最低。不同水分条件下，相同土壤磷流失潜能也不同：淹水条件土壤磷流失潜能最高，其次为先干后湿条件和先湿后干条件，好气条件和淋溶最低。各种条件下土壤磷流失潜能均随施磷量的增加而增大。施肥初期或土壤环境变化初期，土壤磷通过地表径流和优先流流失的风险较高；通过基质流流失的磷在土壤中逐渐向下迁移，故磷流失风险发生在施肥后期。 分段模型（Split Line）方法适合于预测土壤磷通过径流向地表水或通过优先流向地下水体的流失，但不适合预测土壤磷通过基质流的流失。应针对土壤不同水分条件分别使用分段模型方法。若不考虑土壤不同水分条件，则用淹水条件下的临界值较为安全。在预测通过基质流淋失的磷时，使用深层土壤CaCl2-P���含量较使用表层土壤磷含量更为合理。对于红壤，由于在各种培养条件下土壤Bray-P���变化趋势与CaCl2-P���为一致，且土壤Bray-P���分辨度较高，用土壤Bray-P���征磷流失潜能优于Olsen-P��� 综合各种水分条件，红壤土壤磷流失安全值为Bray-P���量低于130 mg kg-1，黑钙土为Olsen-P���量低于138.2mg kg-1，潮褐土为Olsen-P���量低于88.9mg kg-1。

磷素活化剂对黑土磷形态及有效性影响的研究

试验研究了不同温度下活化剂对黑土各形态磷的影响,阐述了活化剂对Olsen-P���响的机制。结果显示,活化剂具有很好的增加土壤中有效磷的能力,在不同的温度条件下作用效果不同,施肥条件下,高温加速磷的固定。10℃时,3种活化剂活化能力为柠檬酸铵>腐植酸>活化剂H2,分别提高土壤Olsen-P���含量达40.93%、33.06%、23.20%;20℃时,活化能力为腐植酸>柠檬酸铵>活化剂H2,分别提高土壤Olsen-P���量达32.35%、24.89%、16.72%;30℃时,与CK相比Olsen-P���量没有明显增加。活化剂能促进各形态无机磷之间的转化,活化能力随温度升高而逐渐降低。SPSS分析结果证实,Al-P���Ca2-P���黑土有效磷的主要组分,与Olsen-P���相关;Ca8-P���负作用,而Fe-P���用效果不显著,但它们仍能通过影响Al-P���Ca2-P���间接影响Olsen-P���