Effect of Phosphorus and Irrigation Levels on Yield,Water Productivity,Phosphorus Use Efficiency and Income of Lowland Rice in Northwest Pakistan

With decreasing availability of water for agriculture and increasing demand for rice production, an optimum use of irrigation water and phosphorus may guarantee sustainable rice production. Field experiments were conducted in 2003 and 2004 to investigate the effect of phosphorus and irrigation levels on yield, water productivity (WP), phosphorus use efficiency (PUE) and income of low land rice. The experiment was laid out in randomized complete block design with split plot arrangements replicated four times. Main plot consisted of five phosphorus levels, viz. 0 (P0), 50 (P50), 100 (P100), 150 (P150), and 200 (P200) kg/hm2, while subplots contained of irrigation times, i.e. 8 (I8), 10 (I10), 12 (I12), and 14 (I14) irrigation levels, each with a water depth of 7.5 cm. Mean values revealed that P150 in combination with I10 produced the highest paddy yield (9.8 t/hm2) and net benefit (1 231.8 US$/hm2) among all the treatments. Phosphorus enhanced WP when applied in appropriate combination with irrigation level. The highest mean WP [13.3 kg/(hm2?mm)] could be achieved at P150 with I8 and decreased with increase in irrigation level, while the highest mean PUE (20.1 kg/kg) could be achieved at P100 with I10 and diminished with higher P levels. The overall results indicate that P150 along with I10 was the best combination for sustainable rice cultivation in silty clay soil.     

中国茶产业政策与全要素生产率变动

梳理了1986—2018年我国茶产业政策变迁趋势,并利用数据包络分析法测算了我国茶产业的全要素生产率,使用Tobit模型检验了茶产业政策对全要素生产率变动的影响。结果表明：（1）产业政策数量能够显著提升茶产业全要素生产率,这一促进作用在解决了内生性后依然存在;（2）鼓励型政策数量和直接政策数量对茶产业全要素生产率的影响具有持久性,限制型政策数量和间接政策数量对茶产业全要素生产率的影响具有时滞效应;（3）直接政策对茶产业全要素生产率的影响最大,间接政策对茶产业全要素生产率的影响最小。为提升茶产业全要素生产率,应加强政策支持,提高产业政策时效性。     

巴基斯坦宜茶区域的气候特点和茶树栽培的关键技术

本文根据在巴基斯坦(Pakistan)曼赛拉(Mansehra)贝达蒂(Bedadi)3年多的茶树试种实践和建园15公顷的经验,认为当地5、6月间的高温干旱,是影响茶树生长的主要障碍。苗期遮荫,用营养钵培育壮苗,秋冬季移栽建园,是茶树栽培的关键技术。     

农业科研单位科研项目管理中存在的问题与对策

科研项目管理是科学研究的重要组成部分,对科学研究、科技发展以及自主创新能力的增强具有重要作用。分析农业科研单位科研项目管理中存在的问题,从加强科研项目全过程服务、打造高绩效的科研团队、完善科研评价机制、提高科研管理人员的综合素质4个方面提出应对策略,实现农业科研单位科研项目管理工作的可持续发展。     

江西滨湖地区籼粳杂交稻品种适应性和丰产性鉴定与分析

为鉴定江西滨湖地区单季粳稻的适应性和丰产性,对8个籼粳杂交稻品种生产力开展了评价试验。结果表明,这8个籼粳杂交稻品种均可在江西滨湖地区作单季稻种植,但产量差异显著,甬优系列品种具有较强的适应性和丰产性。其中,甬优12、甬优1538表现出超强的生产潜力,在滨湖地区种植优势明显。     

广西农村供水工程建设管理思路

分析了当前广西农村供水工程建设管理过程中普遍存在的问题;借鉴各地的典型做法,从项目规划、前期工作、投资筹措、水价管理、机构建设、电力安装等方面探讨解决问题的思路和对策。     

长期绿肥还田对江南稻田系统生产力及抗逆性的影响

 依据江南丘陵地区双季稻田28年（1981-2008年）长期绿肥还田的田间定位试验和4年的养分耗竭盆栽试验,分析比较了长期不同量绿肥还田对稻田系统生产力和抗逆性的综合影响。结果表明,常量绿肥还田和高量绿肥还田处理下,早稻、晚稻和历年的全年平均籽粒产量和生物学产量及其变异系数与长期单施化肥处理差异不显著,但由于绿肥还田处理施用绿肥替代部分化肥,平均每年的化肥N、P和K投入量比单施化肥处理分别减少90.0、9.9和72.0 kg/hm2。绿肥处理的双季稻全年产量呈上升趋势,而长期化肥处理则呈下降趋势,且前者的全年产量可持续性产量指数均略高于后者,常量绿肥还田下稻田系统的耐瘠能力也显著高于长期单施化肥处理。不同量绿肥还田下稻田系统生产力差异不显著,但耐瘠能力常量还田处理较高。     

晋北丘陵山区马铃薯高产高效生产关键技术

晋北地区是山西马铃薯的主要产区,约占全省马铃薯种植面积的50%,但大部分丘陵山区由于生产条件差,生产方式粗放,生产力水平提升缓慢,单产低而不稳的问题一直没有得到很好的解决。本文简要分析了晋北地区马铃薯生产的优势与问题,从选择品种、水肥管理、种薯处理、规范化生产、病虫害防治及收获,提出了该地区马铃薯高产的关键技术措施,以达到指导生产,提高农民经济效益的目的。     

Restoring the Land Productivity of Eroded Land through Soil Water Conservation and Improved Fertilizer Application on Pothwar plateau in Punjab Province,Pakistan

Abstract

Crop production in a rainfed area is constrained by inappropriate management of soil and water by the resource-poor farmers. The present study addresses this issue through integration of practices for soil water conservation (SWC) and soil fertility enhancement as well. Extensive experimentation on wheat-maize was undertaken for two years (2004?2006) on the fields of eight farmers representing two soil types; Rajar (Typic Ustorthent; USDA soil taxonomy) and Guliana (Udic Haplustalf; USDA soil taxonomy) in the Gujar Khan Tehsil of Rawalpindi District, Pakistan. Four treatments consisting of: no SWC +farmer’s rate of fertilizer application (FP), no SWC+improved fertilizer application (IF), SWC practices i.e., deep plowing, bund improvement, plowing across contour+FP (SWC+FP) and SWC+IF. Wheat and maize grain yields in SWC and IF were statistically higher than in the treatments with no SWC and FP, respectively. Compared with the control without any treatment, increase in water use efficiency of both maize and wheat crop was higher in SWC+IF followed by IF alone. On the average, Guliana soil series showed better response to all treatments than Rajar soil. The integrated application of SWC and IF practices increased crop yields in the rainfed area.     

特大型沼气工程温室气体减排效益分析——以“海南澄迈日产3万Nm3车用沼气项目”为例

根据国际通用的温室气体减排计算方法,对海南澄迈日产3万Nm3车用沼气工程所带来的主要温室气体减排量和减排效益进行了估算分析。结果表明：项目每年可减少温室气体排放53 560 t(CO2当量),以上海碳交易市场近年平均交易价格(39.23元/t CO2)计算,可带来210.12万元的经济效益。     

Annual Nutrient Balance and Soil Chemical Properties in Heavy Multiple Cropping System in the Coastal Area of Southeast Lake Dianchi,Yunnan Province,China

Abstract

To ensure higher yields, farmers in China have increased cropping intensity with a large input of chemical fertilizer and livestock manure since 1980s, which has led to unsustainable agricultural productivity and environmental quality. This study aimed to evaluate the effects of intensive cropping on nutrient absorption and biomass production of crops and to determine the controllable source of residual nutrients in soil in the coastal area of Lake Dianchi, China. Soil and crops were sampled in 32 vegetable fields and four paddy fields; and simultaneously surveyed. In vegetable fields, cropping intensity and input to each crop were extremely high; and, 58, 72, and 20% of nitrogen, phosphorus, and potassium were not absorbed by the crop. Nitrogen absorption ratios of the vegetables were low. The amount of nitrogen absorbed from sources other than chemical fertilizer by vegetables, namely, from soil, manure, or irrigation water, in the fields with three to nine years cultivation duration was higher than those with zero to two years cultivation duration. Reduction of input should be more efficient than enhancing output to decrease soil nitrogen, phosphorus, and potassium; and, reducing input of chemical fertilizer should be more efficient than reducing input of manure. These results should be helpful for reducing agricultural pollution in China.