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1.
The increased recognition of the importance of soil is reflected in the UN Post‐2015 Development Agenda with sustainable development goals that directly and indirectly relate to soil quality and protection. Despite a lack of legally binding legislation for soil protection, the European Commission remains committed to the objective of soil protection. However, the achievement of a legally binding framework for soil protection relies on the implementation of a soil monitoring network (SMN) that can detect changes to soil quality over time. As beneficiaries do not pay for the provision of soil information, the options for soil monitoring are limited. The use of existing data sets should be considered first. Using Ireland as an example, this research explored the opportunities for a SMN for Ireland considering three existing national data sets. The options for a SMN are considered in terms of their spatial and stratified distribution, the parameters to be measured and an economic analysis of the options proposed. This research finds that for Ireland, either a 10 or a 16 km2 grid interval stratified by land use and drainage class offers the best potential in relation to the spatial distribution of existing data sets to reflect local data at a national level. With existing data, the stratified SIS data using the 16 km2 grid offers the best value for money, with baseline costs for analysis, excluding field costs, of between €706 481 and €2.8 million. Acknowledging the impossibility of measuring all parameters with ideal frequency, this study proposes a two‐tier system for optimized monitoring frequency. Parameters must anticipate future policy requirements. Finally, the implementation of a SMN must be accompanied by standardized methods, defined thresholds and action mandates to maintain soil quality within allowable limits.  相似文献   
2.
上虞市海涂实验农场中心试验区的排水系统,能满足十年一遇的年最大24h降雨,两天内排出的要求。滨海盐土的地下水位高,农田基本建设除用浅、密的排水沟布置外,还应结合平整土地、发展灌溉以及适用的农、林技术等综合措施,才能达到治盐改土的效果。  相似文献   
3.
田丰 《湖南农机》2016,(7):173-174
随着国内城市化的推进,市政工程的给排水工程越发显得重要。传统的给排水施工技术已经无法满足城市发展要求,社会对给排水的施工质量提出了更高地要求。文章结合当前给排水施工管理现状,对给排水施工的施工管理各方面进行简要探析。  相似文献   
4.
The change in the Common Agricultural Policy (CAP) of the European Union from product to producer support, including requirements for ‘good agricultural and environmental conditions’ and ‘greening’, is excellent. However, these requirements are now defined in rather general terms. Questions can be raised about suitable indicators, and there is a recognized need for effective management recommendations to support farmers in achieving the required ‘good’ conditions. These recommendations are bound to be quite different for different soils in different countries. A study of Dutch clay soils was based on a storyline describing current problems and management options for improvement, which were quantified using a soil–water–crop simulation model. Indicators were defined for agricultural conditions and suggestions made for the use of the model in a predictive mode to help farmers improve their soil management. Environmental conditions were judged by current environmental guidelines for water and air. When modelling, implicit assumptions that soils are homogeneous were shown to be unrealistic for these clay soils, requiring development of innovative methods and procedures, presenting a challenge for soil research.  相似文献   
5.
随着膜下滴灌技术在新疆的大力推广应用,灌排模式发生了改变,从而导致了新的土壤次生盐渍化问题。在阐述新疆3种排水措施——明沟排水、暗管排水和竖井排灌发展的基础上,分析了目前新疆节水灌区农田排水措施存在的问题,结合南疆某一节水灌区灌排试验,分析了排水措施对土壤盐分及地下水位、矿化度的影响,为当地灌排模式提出合理化建议,且为减轻节水灌区的土壤盐渍化提供参考借鉴。  相似文献   
6.

Objective

To describe the use of small-bore wire-guided catheters in the management of peritoneal effusion in cats and dogs and to detail any associated adverse events.

Design

Retrospective study.

Setting

University teaching hospital

Animals

Forty-five client-owned animals that had peritoneal catheters placed for management of peritoneal effusion between July 2010 and June 2021.

Interventions

None.

Measurements and Main Results

Forty-five cases were included (25 dogs and 20 cats). Twenty-eight animals had the catheter placed to aid management of a uroabdomen, 8 of which recovered without surgical management, 11 had the catheter placed to allow autotransfusion of hemoabdomen, 3 had peritonitis, and 3 had ascites secondary to cardiac disease. Twenty-seven cases (15 dogs and 12 cats) received sedation (n = 24) or local anesthesia alone (n = 3) to facilitate catheter placement, and 6 cases had the catheter placed while under general anesthesia. Median length of catheter persistence was 24 hours (range: 2–144 h). The most common adverse events reported were impaired drainage (n = 7) and leakage at the insertion site (n = 4).

Conclusions

Peritoneal catheters can be inserted percutaneously for management of peritoneal effusion. Indications include stabilization and conservative management of uroabdomen, and autotransfusion. They can often be placed with minimal or no sedation and adverse events appear infrequent in occurrence.  相似文献   
7.
A study of the water balances of The Fayoum irrigated lands and Lake Qarun was made to investigate the management of the irrigation system and the efficiency of irrigation water use. The two water balances are strongly interrelated. The drainage flow to Lake Qarun and the water level of the Lake are in delicate balance. A rise in Lake level causes the inundation of adjacent land. Management of The Fayoum water balance assumes control over irrigation water flows, but this control has technical and organizational limitations. Also discussed is the influence of irrigation practices in The Fayoum on the water balance (e.g., the autumn flushing of fields and farmers' preference for not irrigating at night in winter). Notwithstanding a high overall efficiency, irrigation efficiency during the winter is low. The reasons for this are given, together with the constraints against improving system management. Improved uniformity of the division and application of irrigation water will enable a better technical control of flows and will result in better water management in The Fayoum. Abbreviations: FID — Fayoum Irrigation Department, 1 feddan (fe) — 0.4 ha, 1 mcm — 1 million cubic metres: an average annual flow of 3.17 m3/s gives 100 mcm, m3/fe.year — supplied volume (m3) per surface area (fe) per year: 1000 m3/fe.year equals 240 mm/year, MSL — Mean Sea Level  相似文献   
8.
灌溉试验站规划的有关问题   总被引:1,自引:0,他引:1  
根据全国的气候、农业、水利及经济发展水平等区划,合理地选择各省的中心站及重点试验站,并对其进行科学地规划设计,对于总体把握我国灌溉试验基础数据尤为重要。针对目前正在全国进行的灌溉试验站网规划,对省级中心站及重点站的课题规划、试验站的总体布置及设施设备规划和做好本次规划的其他有关问题进行了探讨。  相似文献   
9.
Crop tolerance to land submergence is an important criterion for designing a surface drainage system for agricultural lands. This paper collates the available data from various places in India related to the studies on the submergence tolerance of crops. The paper hypothesizes that a piecewise linear model could be used to describe crop response to land submergence. According to this hypothesis, there would be no yield decline for a few initial days of submergence. If submergence continues beyond this period then there would be linear decline in yield. The unknown parameters in the model are: optimum yield, threshold time and the slope which represents the per cent yield reduction per day of additional submergence beyond the threshold.Data in respect of wheat, pigeon peas, cowpeas, pearlmillet, maize and groundnuts indicate that the model describes the data well, although in many cases the threshold is 0.0. The yield reduction varies from 5.3 to 23.2% for each day of submergence beyond the threshold. It appears that to allow for more than 1–2 days of submergence will result in more than 10% reducation in yield of dryfoot crops. For the maize crop, the seedling stage is the most sensitive stage followed by the silking stage. The grain formation stage is the least sensitive, although even at this stage the threshold is 0.0 and yield reduction is 9.3% for each day of submergence beyond the threshold. The data for 9 test crops from Texas and Venezuela were well described by the model. It is concluded that the piecewise linear model is a useful tool for describing submergence tolerance of crops and for working out surface drainage requirements for a given level of yield reduction. Frequency analysis of the daily rainfall data from some selected locations indicates that there is every likelihood of submergence at most of the stations. It is suggested that there is an urgent need for developing wet farming techniques analogous to dry farming techniques.  相似文献   
10.
Land retirement is ceasing irrigation withthe goal of reducing load, in general, ofdissolved constituents and, in particular,of trace elements, present in subsurfacedrainage generated from irrigated lands. Retirement is achieved through a process ofgoal setting, strategy development anddetermining effects, developing landselection criteria, implementation, andmonitoring. In this study, effects of landretirement are evaluated using hydrologic,soil and economic models as well as resultsfrom a field demonstration study. From themodeling and field monitoring, a process isdeveloped to meet the goals of a landretirement program in the San JoaquinValley of California.Potential negative effects listed for landretirement included loss of agriculturalproductivity, perhaps permanently, and lossof revenue to surrounding communities. Uncertainties included those associatedwith reuse of retired lands as wildlifehabitat, with retired-land maintenanceincluding dust control, with potentialpreservation of retired lands in reservefor future re-introduction to irrigated ordry-land agriculture, and withinstitutional changes concerning repaymentof federal and state water contracts. Benefits would accrue from economic returnto the landowner from the sale of property,the sale or lease of irrigation watersupply, the reduced cost of handlingdrainage, and allocation of freed-up waterto beneficial uses, and the reduced risk ofselenium exposure to fish and wildlife.A recommended sequential approach to selectand manage retired land is to identifyprimary objectives; formulate and implementarea-specific land retirement scenarios;measure biologic, hydrologic, soils andeconomic consequences in the short term andthe long term and manage and monitorretired lands based on dynamic biologic,hydrologic and soil conditions.  相似文献   
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