Changes in soil phosphorus fractions across a toposequence in the estuary plains of Pakistan

Understanding the regional dynamics of soil phosphorus (P) chemistry is essential for developing the best fertilizer management practices aimed at enhancing P use efficiency in cropping systems. The soil content of apatite, an important P-containing lithogenic mineral, can be influenced by its position in the local relief of a landscape. The objective of this study was to determine quantitative distribution of various P-forms in estuary plains of southern Pakistan in relation to soil genesis. Soils at different positions within the estuary plain were sampled at various genetic horizons. Apatite-P was the most abundant inorganic P constituent (380-590 mg kg^?1) in all cases, followed in decreasing abundance by iron oxides surfaces adsorbed phosphorus (Fe-P), octacalcium phosphates (Ca₈-P), aluminum oxides with surface bound P (Al-P) and the least abundant was the phosphorus occluded in iron oxides mineral (Occl-P). The abundance of apatite-P and these other forms of secondary phosphate varied for the soils at different relief positions in these estuary plain landscapes.     

郑汴一体划区域内的土地资源优化配置研究

在中部崛起战略的带动下河南地区特别是郑汴地区社会经济发展取得了显著成就,当前郑汴一体化正在积极推进和实施中。但是目前中国经济发展过程中也存在比较棘手的问题,即人地矛盾突出。针对该问题,该文从中原地区和郑汴2地实际情况出发,探讨郑汴一体化地区土地资源优化配置的途径,提出针对郑汴一体化区域内土地资源优化配置的具体措施,以提高土地利用的综合效益。     

Zero tillage impacts in India's rice–wheat systems: A review

To date, the most widely adopted resource conserving technology in the Indo-Gangetic Plains (IGP) of South Asia has been zero-tillage (ZT) wheat after rice, particularly in India. The paper reviews and synthesizes the experience with ZT in the Indian IGP. ZT wheat is particularly appropriate for rice–wheat systems in the IGP by alleviating system constraints by allowing earlier wheat planting, helping control the weed Phalaris minor, reducing production costs and saving water. ZT wheat after rice generates substantial benefits at the farm level (US$97 ha⁻¹) through the combination of a ‘yield effect’ (a 5–7% yield increase, particularly due to more timely planting of wheat) and a ‘cost savings effect’ (US$52 ha⁻¹, particularly tillage savings). These benefits explain the widespread interest of farmers and the rapidity of the diffusion across the Indian IGP, further aided by the wide applicability of this mechanical innovation.     

Performance of Turmeric and Soil Moisture Depletion Pattern Under Different Water Regimes and Nutrient Sources at New Alluvial Zone of Indo-Gangetic Plains,India

In India, the production of turmeric is not even half compared to its potential. To analyze the possibilities for higher production in turmeric, this study was conducted at the BCKV, Gayeshpur, West Bengal, during 2011 and 2012, to evaluate the effect of irrigation scheduling (0.6, 0.9, and 1.2 irrigation water (IW)/cumulative pan evaporation (CPE) and rainfed) in main plots and nutrient management [100% inorganic, 75% inorganic + 25% FYM (Farm yard manure), and 50% inorganic + 25% FYM + 25% vermicompost] in subplots on soil moisture depletion and productivity of turmeric. The highest value of fresh rhizome yield (23.90 kg ha^?1) and qualitative indices were obtained with irrigation schedule at 0.9 IW/CPE ratio water regimes and 50% inorganic + 25% FYM + 25% vermicompost. The correlation coefficients of water use and yield of turmeric were found at 0.943. The combination of 0.9 IW/CPE and 50% inorganic + 25% FYM + 25% vermicompost improved the overall performance of turmeric crop.     

江汉平原苏丹草-黑麦草轮作中氮磷钾肥效果及养分利用率

本试验研究了江汉平原苏丹草-黑麦草轮作制中氮磷钾肥配合施用效果及养分利用率。结果表明:氮磷钾配施(NPK)的饲草鲜草产量分别比不施氮(PK)、不施磷(NK)和不施钾(NP)增产123.3t/hm²、34.5t/hm²和24.7t/hm²;氮、磷和钾肥显著增加鲜草、干草产量,鲜草增产率分别为313.1%、26.9%和17.9%,干草增产率分别为196.3%、22.2%和9.7%;氮磷钾配施显著促进饲草对氮、磷和钾的吸收,3种养分两季吸收总量分别达到500kgN/hm²、208kgP₂O₅/hm²和1196kgK₂O/hm²;氮磷钾配合施用条件下苏丹草和黑麦草的养分吸收比例(N:P₂O₅:K₂O)分别为1:0.37:1.96和1:0.50:3.19;轮作体系中,N、P、K肥利用率分别为60.0%、21.7%和61.6%;氮、磷和钾肥对饲草吸收相应养分的贡献率分别为81.0%、32.7%和23.2%。     

京冀平原区不同类型农户耕地利用决策影响因素分析

农户土地利用目标转型的影响因素及其决策机制的研究,是科学分析区域耕地资源质量和生产能力驱动变化的基础。该文选择京冀平原区的北京市大兴区和河北省曲周县为研究样区,以典型乡镇农户调研数据为基础,采用二项Logistic回归模型,分析农户家庭、农户收入、农户土地资源状况和农户区位条件等因素对不同类型农户耕地利用决策的影响。研究结果表明：曲周主要的农户类型为粮食和利润协调型,大兴的主要农户类型为粮食和利润协调型农户和利润需求型。研究区域农户为了获得更高的农业收益,偏好于增加耕地的劳动力投入、农药投入、复种指数较高。农户家庭农业劳动力数量、耕地面积、土地质量和交通通达度对农户做出“保证家庭消费粮食的基础上,增加经济收入”和“只是为增加更多的收入”的耕地利用目标决策有显著的积极作用,即对于粮食和利润协调型农户或利润需求型农户有积极作用;城镇影响度对农户从粮食和利润协调型向利润需求型过渡和转型有积极作用。     

利用水均衡法确定建设项目水资源论证范围

建设项目水资源论证制度是完善取水许可制度,审查批准取水许可申请的重要依据。论证过程中,应首先确定论证范围。该文针对平原区特有的水文地质条件,提出应用水量均衡原理,以待定的水源地稳定水位降落漏斗面积为均衡区面积,建立水量均衡方程,进而求得该漏斗区面积,以此作为确定水资源论证范围的依据,具有较强的实用性。     

成陆时间和沉积环境对宁绍平原水耕人为土形成的影响

为了解低平原地区水耕人为土分布的空间规律,以宁绍平原为例,探讨了成陆时间和沉积环境对水耕人为土性状与剖面发育的影响。田间调查表明,宁绍平原因成陆时间和成因的差异可被划分为近代浅海沉积区、低洼湖沼沉积区、古水陆相沉积区和古滨岸河湖沉积区等4种沉积环境,相应地分布的水耕人为土类型及性状有较大的差别。近代浅海沉积区主要分布普通简育水耕人为土,其性状变化与海涂围垦时间有关。低洼湖沼沉积区主要分布普通潜育水耕人为土或底潜简育水耕人为土,其性状的差异主要与距古湖沼中心距离有关。古水陆相沉积区主要分布普通铁聚水耕人为土,局部区域因上层滞水可形成铁聚潜育水耕人为土。古滨岸河湖沉积区的土壤类型主要为普通铁聚水耕人为土或普通简育水耕人为土。研究认为,通过沉积环境的识别有助于低平原地区水耕人为土类型的鉴定。     

中原牡丹不同品种花期与其其他生物学性状的关系研究

[目的]汇集和研究牡丹种质资源,研究牡丹花期与其其他生物学性状的关系。[方法]采用比较法分析收集到的牡丹品种的生态适应性。采用数量分类法进行品种分类。[结果]从种质资源圃的818个牡丹品种中鉴定出576个,其中早花品种58个,中花品种400个,晚花品种118个。早、中、晚品种的花色均以红色系、紫红色系为主。早花品种的花型以荷花型、菊花型、蔷薇型居多,株型以半开张型为主,叶型分布较均匀,多数生长势较强;中花品种的花型以皇冠型、绣球型居多,株型以半开张、直立型为主,叶型以中形长、圆叶型为主,生长势以中等为主;晚花品种的花型以皇冠型、绣球型为主,株型以半开张型为主,叶型以中形长叶型较多,生长势有弱化的趋势。[结论]解决了"同物异名,同名异物"的现象,明确了牡丹不同品种花期与花色、花型、花态、株型、叶型、生长势的关系。     

黄淮海平原小麦棉花两熟制生产力研究

改革耕作制度,提高复种指数是扩大生产面积的一条有效途径。韩湘玲等（１９８６）对黄淮海平原粮食生产力做过研究〔２〕,得出一年两熟比一熟生产力高近１倍的结论。黄淮海平原麦棉两熟种植也形成规模生产,产生了显著的社会经济效益。本试验旨在研究该平原麦棉两熟制生产力。１　材料与方法１．１　试验地点于１９９６～１９９７年在黄淮海平原主产棉区的优质棉基地县安排５个试验点。南部是扶沟县（３４（０５′Ｎ）、商丘县（３４°２７′Ｎ）和巨野县（３５°２５′Ｎ）;北部是安阳市（３６°０７′Ｎ）、威县（３６°５１′Ｎ）。各…