Strategies to encourage better use of nitrogen in animal manures

Abstract. Research conducted in the MAFF Nitrate Programme has been used to formulate new and improved guidelines on the efficient use of manure nitrogen (N). In order to reduce nitrate leaching losses, manures containing large amounts of available N (i.e. slurries and poultry manures) should not be applied to free-draining soils in the period from autumn to early winter. Also, for efficient nutrient utilization manure application rates should be consistent with agronomic requirements (up to 250 kg total N ha⁻¹ yr⁻¹). Existing farm machinery was shown to be capable of applying manures evenly to grassland and arable stubbles, but required an accurate estimate of application rate and the careful matching of spreading widths. To provide growers with detailed guidance on the fertilizer N replacement value of manures the computer-based decision support system MANNER (MANure Nitrogen Evaluation Routine) has been developed. The much improved understanding of manure N losses and availability has been summarized in a series of 'Managing Livestock Manures' booklets, the MAFF Fertilizer Recommendation booklet and the Codes of Good Agricultural Practice.     

植物源杀菌包膜复合肥对番茄生长、氮肥利用率及病害的影响

利用植物源杀菌材料作为包衣剂研制出杀菌包膜复合肥, 在番茄小区试验中研究了其杀菌及对番茄生长的影响。结果表明: 各杀菌包膜复合肥处理(分别用ZYF1~ ZYF5 表示)均能有效延缓养分的释放, 与施普通复合肥处理(CK1)相比各杀菌包膜复合肥处理土壤硝态氮在番茄生长后期仍能保持较高含量。除ZYF4 处理外, 其余杀菌包膜复合肥处理番茄产量均明显高于CK1, 其中ZYF3 处理番茄产量最高, 达11.1 kg·m^-2, 较CK1 高16.8%。各杀菌包膜复合肥处理的氮肥利用率也均大于CK1(33.3%), 其中ZYF2、ZYF3 处理分别较CK1 处理高9.9 个和9.5 个百分点。各杀菌包膜复合肥对番茄的Vc 含量无显著影响, ZYF1 处理显著降低了番茄的硝酸盐含量, 而ZYF2、ZYF4、ZYF5 处理则促进了番茄对硝酸盐的累积。各杀菌包膜复合肥处理显著降低了番茄枯萎病、灰霉病的发病率, 其中ZYF1 处理对这两种病菌均有较高的抑制作用, 使发病率较CK1 分别下降17.7 个和12.5 个百分点。     

An enhanced software tool to support better use of manure nutrients: MANNER‐NPK

MANNER‐NPK (MANure Nutrient Evaluation Routine) is a decision support tool for quantifying manure (and other organic material) crop available nutrient supply. The user‐friendly design of an earlier version of MANNER was retained, but in response to user and stakeholder feedback, additional functionality was included to underpin new and revised nitrogen (N) transformation/loss modules (covering ammonia volatilization, nitrate leaching and nitrous oxide/di‐nitrogen emissions, and organic N mineralization) and also to estimate manure phosphorus (as P₂O₅), potassium (as K₂O), sulphur (as SO₃) and magnesium (as MgO) supply. Notably, MANNER‐NPK provides N availability estimates for following crops through the mineralization of organic N. Validation of the crop available N supply estimates was undertaken by comparing predicted values with data from more than 200 field experimental measurements. For cattle, pig and poultry manures, there was good agreement (P < 0.001) between predicted and measured fertilizer N replacement values, indicating that MANNER‐NPK provides robust estimates of manure crop available N supply and N losses to the wider environment.     

基于无人机图像的多尺度感知麦穗计数方法

小麦是世界上重要的粮食作物,其产量的及时、准确预估对世界粮食安全至关重要,小麦穗数是估产的重要数据,因此该研究通过构建普适麦穗计数网络(Wheat Ear Counting Network,WECnet)对灌浆期小麦进行精准的计数与密度预估.选用多个国家不同品种的麦穗图像进行训练,并且对数据集进行增强,以保证麦穗多样性...     

基于穗粒分布图的玉米果穗表型性状参数计算方法

玉米果穗表型性状是玉米育种、产量预测的重要参数,提出一种基于穗粒分布图的玉米果穗性状计算方法,全面解析玉米果穗和穗粒的几何、数量和颜色等表型性状。该文利用步进电机驱动果穗转动来获取果穗主要侧面图像,采用果穗畸变校正方法生成标准果穗图像序列,在像素尺度进行果穗轮廓分析,建立图像序列中果穗轮廓映射关系并生成果穗三维模型,在穗粒尺度拼接果穗整个表面的穗粒分布图,计算出果穗和穗粒的各项表型性状。试验结果表明,提出的表型性状计算方法对穗型及穗粒分布规则的玉米果穗具有较高检测精度,其中穗行数、行粒数、总粒数、果穗长和果穗粗的平均计算精度分别为98.231%、94.351%、96.921%、98.956%和98.165%。     

Preliminary studies on triticale,wheat, barley,and rye responses to lime and N.

Abstract

The lime and N requirements for triticale (X Triticosecale Wittmack) have not been established because of the relatively short history of the crop. This study was designed to evaluate the effects of lime and high N rates on triticale, wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and rye (Secale cereale L.) on Dickson silt loam (Typic Paleudult) and Decatur silty clay loam (Rhodic Paleudult) in 1974–1976. The soils had pH values of 4.9 and 5.5 with no lime and 5.4 and 5.8, respectively, when limed as recommended. The fertilizer rates were 112, 140, and 170 kg N/ha. Yields and N, P, K, Ca, Mg, Mn, Fe, Al, Zn, Cu, and B were determined in straw and grain. Liming the Dickson soil increased the straw yields of barley at 112 kg N/ha and grain yields of the cultivars generally at the 170 kg N/ha rate. Liming the Decatur soil did not have consistent effects on straw yields but increased the grain yields of the wheat and rye cultivars. Increasing N rate increased the straw yields of wheat on Dickson but decreased the grain yields of barley in the same soil with no lime. Nitrogen fertilization did not have consistent effects on the Decatur soil. The N, P, K, Ca, Mg, and Mn compositions suggested that more differences occured at the species level than at the cultivar level.     

Field evaluation of soil moisture deficit thresholds for limits to trafficability with slurry spreading equipment on grassland

This study investigated the extent of soil damage caused by field traffic associated with different levels of soil moisture deficit (SMD). The hybrid SMD model was used for computing temporal patterns of SMD which can be accurately predicted for a range of soil types in Ireland. The aim of this study was to determine SMD threshold limits to trafficability for incorporation into a decision support system for safe slurry spreading. A tractor and a fully loaded single‐axle slurry tanker (total weight ca. 18 tonnes) were driven over well, moderate and poorly drained soils at SMD values of 0, 5, 10 and 20 mm during drying phases. The change in soil bulk density (SBD) was used as an indicator of soil compaction, and rut profile measurements were taken to determine soil deformation indicative of surface damage. The effect of traffic on the grass crop was determined by measuring dry matter yield at 30 and 60 days posttraffic in the wheel‐rut and nontrafficked area. Results showed that the SMD at the time of traffic had a significant (P < 0.05) effect on the magnitude of the changes in SBD on soils of different drainage status, and on rut dimensions following traffic. DMY was significantly (P < 0.05) reduced on the wheeled compared with the nonwheeled soil. No differences in the magnitude of DMY loss were identified between the sites having different drainage status. An SMD value of 10 mm was suggested as an SMD threshold for trafficability for safe slurry spreading purposes.     

基于全景图像的玉米果穗流水线考种方法及系统

为提高玉米果穗考种效率和精度,该文提出一种基于全景图像的玉米果穗流水线考种方法和系统。利用托辊传送装置实现果穗自动连续推送,基于工业相机自动检测果穗运动状态并实时采集图像,获取覆盖果穗全表面的图像序列;建立果穗运动、摄像机成像、表面拼接关系,从图像序列中抽取果穗中心畸变最小区域拼接出果穗表面全景图像;最后,结合果穗边界检测、籽粒分割和有效性鉴定等技术提取出果穗表面上有效籽粒。试验结果表明,该文方法和系统较好地平衡了玉米果穗考种的效率和精度,图像采集和计算平均效率达15穗/min和4穗/min,穗长和穗行数指标计算精度可达99%和98.89%,可为研发全自动、高通量玉米果穗表型检测装置提供有益借鉴。     

Possibilities for modelling the effect of compression on mechanical and physical properties of various Dutch soil types

The state of compactness of the arable soil layer changes during the growing season as a result of tillage and traction. The aim of this study was to assess and predict some soil mechanical and physical properties governing machine performance and crop response. The following mechanical properties were studied: compressibility, workability and cone index, CI, the latter as indicator of load-bearing capacity or root penetration resistance. Compressibility of the soil could be described as a semi-log function of pressure versus air volume and moisture content, with texture-specific coefficients for three representative soils, in the range of 6–35% air content. The wet workability limit for 16 Dutch soils was reached when the compaction process turned from “dry” into “wet” at 408 kPa of pressure. Soil rebound after pressure release was taken into account and quantified. Semi-log relations were found for CI versus porosity and moisture. Other physical properties were also studied and it was found that the nature of the pF curve of three representative soils (for seven levels of bulk density) was highly affected by the initial seven pressure–moisture combinations. The “effectivity” of the pore system, indicating the effect of tortuosity and discontinuity on the oxygen diffusion rate, turned out to be proportional to air content in the range of 6–25%. Critical machine and plant related limits for aeration and mechanical resistance, CI, are available from the literature. Aeration is associated with minimum values for air volume and oxygen diffusion rate, respectively. Using this information, CI was associated with minimum values for load-bearing capacity and maximum values for root penetration.The applicability of the comprehensive laboratory approach is found in farming practices and evaluations of land management systems. On the operational level, machine performance can be predicted more accurately under fluctuating soil conditions. Also, the effects of modified equipment can be quantified more accurately in the case of unchanged field conditions. The same holds true for the prediction of crop response, as it is influenced by aeration and mechanical limits for plant growth. It was concluded that the approach of predicting the mechanical behaviour of soil, followed by the pF-derived determination of physical properties, will do justice to the dynamic character of the soil structure related input parameters in the present and future models and simulations for machine performance, crop production and soil conservation.     

超级稻精量穴盘播种机排土器设计与试验研究

针对新型超级稻精量穴盘育秧播种机对穴盘穴孔排覆土的要求,设计了2种排土器,双向4螺旋外槽轮式排土器和带式排土器。在保证每小时450盘(相应的秧盘输送速度为0.075m/s)的生产率情况下,做了不同土壤含水率、不同土壤颗粒尺寸、不同排土间隙对排土效果影响的试验研究。结果表明,对于双向4螺旋外槽轮式排土器,播过5mm筛和过3mm筛的土壤颗粒时,排土间隙分别为3和1mm为宜;对于带式排土器则分别为6～7和5mm左右为宜。2种排土器,均是播过3mm筛的小颗粒土壤的播土均匀性和播土质量要好于播过5mm筛的大颗粒土壤。对于相同颗粒尺寸的土壤,高含水率(13%左右,湿基)的土壤播土质量要好于低含水率(5.72%,湿基)的播土质量,更主要的是可以改善工作环境。在保证不增加高湿土壤处理难度的前提下,建议采用小颗粒湿土进行播土作业。所设计的2种排土器均能满足超级稻穴盘育秧的播土要求,但需要注意对带式排土器的张紧平衡调节,且要避免大于排土间隙的土壤颗粒进入带式排土器中。排土器的播土均匀性可以采用播土高度均值的多重比较检验方法进行评价。     

The use of Krenite to control birch on lowland heaths

Birch invasion is a major problem facing managers of lowland heath in southern England, and herbicides are likely to play a major part in controlling this ‘weed’ species. One herbicide, Krenite, has been tested in two experiments and in larger scale case-study on lowland heaths, and its effect on birch, bracken, and the ground flora noted. In general Krenite produced a good kill of birch, and caused little damage to the underlying Calluna-dominated vegetation, and it appears a suitable herbicide for birch control in lowland heaths, but is less effective against bracken and willows.     

农户土地利用投入变化及其土地利用意愿分析

认识农户土地利用投入的变化规律,把握当前农户的生产意愿,对制订相关政策,确保国家的粮食安全具有重要意义。该文采用分层随机抽取样本的方法,基于湖北省咸宁市1 252个农户家庭的调查数据,从粮食生产过程中涉及到的劳动力、土地资源、农业机械、化肥与农药等生产因素方面,对1981年以来农户的土地利用投入要素的变化特征及当前的土地利用意愿进行了分析。结果表明:近30 a来,农户在土地利用过程中投入的劳动力与用于主要粮食生产的土地面积明显下降,而化学肥料与农药总投入量明显增加;经济因子与农机技术进步是驱动农户行为变化最重要的2个因素,劳动力转移与"三补一免"等惠农政策对农户土地利用投入变化的影响有限;农户农地利用的目标出现显著分化,传统"全民式粮食生产模式"正向"专业化规模化农户生产模式"转变,专业化规模生产农户应是国家惠农政策重点补贴与扶持的对象;国家在进一步促进土地流转的同时,如何有效稳定主要粮食作物的生产面积,需要更加积极的调控对策引导;随着边际土地从农地利用范畴析出,区域性生态好转出现新的机遇,国家宜出台生态用地整理的相关政策,提升区域性生态服务功能。     

Formulation of humic substances coated fertilizer and its use to enhance K fertilizer use efficiency for tomato under greenhouse conditions

A greenhouse experiment was conducted at Land Resources Research Institute, NARC, Islamabad to examine the impact of humic substances (HSs) coating on potassium fertilizers use efficiency. Tomato variety “Rio Grande” was used. The treatments applied were T1= Control (N, P at 250 and100?mg kg^?1 respectively), T2?=?N, P?+?K at 200?mg kg^?1 as SOP, T3?=?N, P?+?K at 200?mg kg^?1 as NPK blend, T4?=?N, P?+?K at 200?mg kg^?1 HSs coated SOP) and T5?=?N, P?+?K at 200?mg kg^?1 HSs coated NPK blend. Results indicated a positive impact of sole and HSs coated products on agronomic traits, nutrient concentration, fruit quality traits, flower number, fruit umber, fruit weight, chlorophyll contents, fresh and dry biomass, tissue water contents, diameter and fruit mineral composition. The response of afore said traits to applied treatment varied.     

Assessing the use of erosion modeling to support payment for environmental services programs

Purpose

Payment for environmental services (PES) has assumed increasing importance in discussions about sustainable development strategies. Many of the PES programs are based on water erosion control and the corresponding environmental and economic benefits generated in the basins where they are implemented. The main objective of this study was to show how erosion susceptibility models can support PES programs.

Materials and methods

The application of the Universal Soil Loss Equation (USLE) in the Sarandi Experimental River Basin (32.7 km²), located in the Federal District, Brazil, was used as a study case. Then a scheme for organizing knowledge about ecosystem services related to erosion control and water resources was performed. Considering the generated scheme, the USLE results, the land use map, and the water use in the region, we evaluated how erosion modeling could support PES programs.

Results and discussion

The results show that a large part of the study basin (90%) presents “low” susceptibility to erosion, which is significant in terms of the use and conservation of ecosystem services, as well as being a limitation regarding the need for the implantation of PES programs for erosion control. Incentives for maintaining the natural vegetation in areas with higher erosion susceptibility have the greatest potential to justify PES programs in the study basin, and the sanitation company is the potential payer for erosion control in the Sarandi River Basin.

Conclusions

The application of the USLE in a spatially distributed form proved to be an important support tool for land management and the implementation of PES policies.     

配施有机肥提高化肥氮利用效率的微生物作用机制研究

采用15N示踪技术和盆栽试验研究了水稻生长期间不同施肥处理土壤微生物量氮的动态变化,探讨了配施有机肥提高化肥氮利用率的微生物作用机制。结果表明,在水稻生育前期,化肥配施鸡粪堆肥、猪粪堆肥和酒糟堆肥较化肥单施均提高了土壤微生物对化肥15N的固持率,降低了土壤矿质态15N含量。而随水稻生育进程推进,在先前被微生物固持的化肥15N化肥配施鸡粪堆肥、猪粪堆肥和酒糟堆肥处理分别有87%、81%和81%被释放,增加了同期水稻对化肥15N的吸收量。化肥配施鸡粪堆肥、猪粪堆肥和酒糟堆肥,化肥15N利用率均超过60%,而单施化肥利用率仅39%。可见,配施有机肥提高化肥氮利用率,其机制之一是通过促进土壤微生物对化肥氮的有效调控,使化肥氮更好地被转化利用。     

基于循环修正的灌溉用水效率综合评价方法

灌溉用水效率是最严格水资源管理制度建设中用水效率控制红线的重要组成部分,也是衡量灌区节水改造进展与效果的重要指标。针对灌溉用水效率评价中存在的单一方法评价结果不一致的难点问题,该文以12个灌区用水水平与用水效率实地调查分析为基础,首先采用突变理论评价方法、熵值法和层次分析法进行灌溉用水效率评价,再以Spearman等级相关系数作为检验标准,利用平均值法、Board法、Copeland法、模糊Borda法4种组合评价方法对单一评价结果进行组合,反复迭代,得到各灌区农业用水效率综合评价排序。最后,根据影响灌区排序的主要指标将灌区分为3类,指出了影响各灌区灌溉用水效率的主要因素及其改进措施,对灌区节水改造与农业用水效率管理具有参考意义。     

使用因素对发动机润滑油劣化影响的层次分析

为了有效控制发动机实际使用过程的润滑油衰变劣化。论文结合层次识别理论对发动机润滑油劣化的实际使用因素进行了识别。通过构建发动机润滑油劣化影响因素的指标体系和层次诊断结构图,运用层次判断矩阵识别出了影响发动机润滑油劣化的主要实际使用因素。结果发现温度是构成润滑油劣化的最主要影响因素,发动机工况变化、外界环境也会对润滑油劣化构成一定影响。     

低植酸作物遗传改良途径与磷资源高效利用

[目的]磷是作物生长发育所必需的营养元素.在植物体内,磷多以植酸形式储存在成熟籽粒中.非反刍动物,包括人类,无法消化植酸来获取磷及植酸螯合的有益元素,籽粒中收获的大量磷素进入人及动物排泄物,不仅造成磷资源浪费,也加大了环境风险.因此,培育籽粒低植酸品种是改善作物营养品质、降低磷素环境风险的重要途径.本文综述作物籽粒磷的...     

The use of Twitter for knowledge exchange on sustainable soil management

Encouraging the uptake of sustainable soil management practices often requires on‐farm experiential learning and adaptation over a sustained period, rather than the traditional knowledge transfer processes of identifying a problem and implementing a solution. Farmer‐to‐farmer learning networks are emerging with farmers experimenting and sharing knowledge about these practices amongst themselves. One potential communication channel for such interaction and knowledge sharing is social media and Twitter in particular. A content analysis of a Twitter account for an EU research project, SoilCare, and in‐depth qualitative interviews with five farmers using Twitter, was used to illustrate the extent and type of farmer‐to‐farmer knowledge sharing in relation to sustainable soil management practices. Evidence of farmer learning and knowledge sharing on Twitter with respect to these practices was identified. Twitter can capture the immediacy of the field operations and visual impacts in the field. Furthermore, the brief messages channelled through Twitter appeal to time‐constrained farmers. The ability for interaction around particular hashtags in Twitter is developing virtual networks of practice in relation to sustainable soil management. Within these networks, farmer champions are emerging that are respected by other farmers. Twitter works best for those actively seeking information, rather than passive recipients of new knowledge. Therefore, its use with other forms of face‐to‐face interaction as part of a blended learning approach is recommended. Twitter also offers a potential space for other actors, such as researchers and advisers, to interact and share knowledge with farmers.