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F.M. Kiziloglu M. Turan U. Sahin Y. Kuslu A. Dursun 《Agricultural Water Management》2008,95(6):716-724
The use of wastewater for irrigation is increasingly being considered as a technical solution to minimize soil degradation and to restore nutrient content of soils. The aims of this study were to test if wastewater irrigation could improve soil fertility without affecting the quality of soils and plants. A field experiment was conducted in 2006 to investigate the effects of irrigation with untreated, and preliminary and primary treated wastewater on macro- and micronutrient distribution within the soil profile, yield and mineral content of cauliflower and red cabbage plants grown on a calcareous Aridisol in eastern Anatolia, Erzurum province, Turkey. Wastewater irrigation affected significantly soil chemical properties in the 0–30 cm soil layer and plant nutrient content after harvest. Application of wastewater increased soil salinity, organic matter, exchangeable Na, K, Ca, Mg, plant available phosphorus and microelements, and decreased soil pH. Wastewater irrigation treatments also increased the yield as well as N, P, K, Ca, Mg, Na, Fe, Mn, Zn, Cu, Pb, Ni and Cd contents of cauliflower and red cabbage plants. The highest yield, macro- and micronutrient uptake of cauliflower and red cabbage plants were obtained with the untreated wastewater. Undesirable side effects such as heavy metal contamination in soil and plant, and salinity were not observed with the application of wastewater. It can be concluded that untreated wastewater can be used confidently, in the short term, in agricultural land, while primary treated wastewater can be used in sustainable agriculture in the long term. 相似文献
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黑土区坡耕地施加生物炭对水土流失的影响 总被引：7，自引：0，他引：7
为了探索生物炭对黑土区坡耕地的水土保持作用效果,于2015年在东北黑土区典型黑土带上的黑龙江省北安市红星农场3°坡耕地上的径流小区内,开展了不同生物炭施用量(0、25、50、75、100 t/hm~2)对土壤结构、持水性能、径流泥沙控制等影响的试验研究。结果表明:生物炭可有效改善黑土区土壤结构,随着生物炭添加量的增加,土壤容重随之减小,而土壤孔隙度则会明显提高;土壤饱和含水率、田间持水量和土壤储水能力均随生物炭施用量的增加而增加;适当施加生物炭对黑土区坡耕地降雨径流及水土流失具有较好的控制作用,75 t/hm~2处理具有最好的径流泥沙控制效果,其中径流控制效果好于泥沙控制;施加生物炭还可以不同程度地减少黑土区坡耕地土壤养分流失,并可以改善养分的空间分布,4种生物炭用量处理的养分含量不仅在数量上高于对照处理,而且在均匀程度上有较大的改善,减缓了坡度对土壤养分造成的坡上与坡下的差异。研究结果为东北黑土区秸秆资源的高效、绿色、循环利用提供了一条新的途径,可为黑土区坡耕地水土流失防治提供理论依据和技术支撑,对该区农业可持续发展具有重要意义。 相似文献
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《Agricultural Systems》1998,56(2):225-251
Human-induced soil salinisation is a major resource degradation issue in Australia. While the processes and remedial activities are generally understood, the pressing questions remain as to whether the problem can be managed and who should take what action. This paper presents an analysis for a catchment in Eastern Australia where dryland salinisation is emerging in the plains. A spatial and dynamic mathematical programming model is developed as a systems analysis tool. The model results establish that salinisation on the plains is caused by water imports from surrounding areas. Salinity imposes severe external costs on affected landholders who have to change their land use systems, both as a response to its emergence and to control groundwater tables. Taking a catchment perspective, it is investigated what contribution different areas within the catchment ought to make to control soil salinisation on the plains. The results indicate that some land use changes for groundwater table control would optimally be implemented in uphill recharge areas but most of the cost would be borne by plains farmers. The results also demonstrate that climatic variability tends to exacerbate salinisation and lower agricultural incomes. 相似文献
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【目的】全面评价土地利用方式对喀斯特峡谷区土壤结构退化的影响。【方法】采用空间代替时间的方法,开展了不同土地利用方式对土壤水稳性团聚体分布特征及稳定性的研究。【结果】①不同土地利用方式均以>0.25 mm粒径水稳性团聚体为主,其量变化、MWD、GMD均表现为林草间作地>荒草地>退耕还草地>耕地;②在不同土层中,不同土地利用方式土壤水稳性团聚体量总体上随粒径的减小呈先增加后减少再增加的变化趋势,其中0~20 cm土层,土壤各粒级水稳性团聚体量分布及稳定性差异具有一定显著相关性,20 cm至母质层差异不显著;③5 mm粒径团聚体成为土壤团聚体从微团聚体向大粒径团聚体团聚化过程中关键的临界点;④GMD可以作为喀斯特峡谷区整个剖面土壤水稳性团聚体稳定性评价指标。【结论】林草间作模式能够增强喀斯特峡谷区土壤结构的稳定性,对防止土壤结构退化具有重要作用。 相似文献
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Sustainable use (in terms of nutrients) of soil resources by farmers in Sub-Saharan Africa is constrained by institutions and markets. This paper explores the case of northern Nigeria, by using a combination of multi-attribute utility theory and bio-economic modelling. This approach allowed us to identify heterogeneity in production strategies and to quantify its effect on the use of soil nutrient resources.We find that farmers with larger land holdings place more emphasis on gross margins in their utility function, while those with larger holdings of fertile fadama fields place more emphasis on sustainability. Risk aversion, operationalised through variance minimization, appears an important attribute in the utility function of many farm households that are more dependent on agriculture for their overall income.A regression analysis shows that differences in production strategies significantly affect nutrient balances, but also shows that such effects are heterogeneous across locations. We find more favourable nutrient balances for some of the more market-oriented farm households who place more emphasis on sustainability. In farm plans of the most risk-averse households, the production of cereals for subsistence consumption dominates and leads to negative soil nutrient balances, especially for potassium.Farmers who place a large importance on gross margins are likely to benefit most from policies aimed at enhancing profitability through improving functioning of markets. The large group of risk-averse farmers will have the largest immediate gain in utility from policies and technologies aimed at reducing production risk in high-value crops. Additional policies aimed at creating a stronger market-oriented production by the least-endowed farm households could play a role in reducing intensity of soil fertility mining. Under these conditions, the efficient cropping pattern shifts partially from cereal cropping to high-value crops, associated with higher input use.The main results are similar to those in other studies, although some of the nutrient balances are less negative. The results do appear to be sensitive to the type of cropping activities included in the analysis, and additional methodological research is required. Extensions of the used method should further account for temporal and spatial differences in soil fertility, leading to differences in nutrient uptake and production, as well as potential temporal heterogeneity in production strategies. 相似文献
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The Office de la Haute Vallée du Fleuve Niger (OHVN) zone in southern Mali is a small but important agricultural production region. Against a background of environmental degradation including decades of declining rainfall, soil erosion, and human pressure on forest resources, numerous farming communities stand out through the use of improved soil and water management practices that have improved agricultural and environmental conditions. Field surveys conducted in 1998–2001 indicated that environmental and agricultural conditions have improved in the past decade. In an effort to better quantify environmental trends, we conducted a study using medium- and high-resolution remotely sensed images from 1965 to 2001 in order to analyze land use and land cover trends in 21 village territories. The trends show clear indications of agricultural intensification and diversification among villages that have received assistance from the OHVN agricultural development agency. Some communities have improved environmental conditions by protecting their forest resources through community management actions. Four decades of remotely sensed images played a practical role in tracking and quantifying environmental and agricultural conditions over time. 相似文献
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Managing water by managing land: Addressing land degradation to improve water productivity and rural livelihoods 总被引：3，自引：0，他引：3
The premise of this paper is that the key to effective water resources management is understanding that the water cycle and land management are inextricably linked: that every land use decision is a water use decision. Gains in agricultural water productivity, therefore, will only be obtained alongside improvements in land use management. Expected increases in food demands by 2050 insist that agricultural production - and agricultural water use - must increase. At the same time, competition for water between agricultural and urban sectors will also increase; and the problem is further compounded by land degradation. A global survey suggests that 40% of agricultural land is already degraded to the point that yields are greatly reduced, and a further 9% is degraded to the point that it cannot be reclaimed for productive use by farm level measures. Soil erosion, nutrient depletion and other forms of land degradation reduce water productivity and affect water availability, quality, and storage. Reversing these trends entails tackling the underlying social, economic, political and institutional drivers of unsustainable land use. This paper is based on a review of global experiences, and its recommendations for improving water management by addressing land degradation include focusing on small scale agriculture; investing in rehabilitating degraded land to increase water productivity; and enhancing the multifunctionality of agricultural landscapes. These options can improve water management and water productivity, while also improving the livelihoods of the rural poor. 相似文献
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寻找环境友好型的土地整治工程修复材料,已经成为国内外土地整治工程领域中的新热点。随着材料科学的飞速发展,有机材料、无机材料、纳米材料、复合材料和生物材料等在土地整治工程领域中的应用越来越受到重视,这些材料由于具有巨大的比表面积、微界面性质、吸附特性、重金属螯合作用和降解有机污染物等特性,在重金属污染、有机物污染物等污染土壤的治理中,以及土壤理化性质的改良中有望发挥重要作用。综述了目前有机材料、无机材料、纳米材料、复合材料和生物材料在土地整治工程领域的应用研究进展,并总结了应用研究的不足,指明了研究方向,为深入研究提供借鉴。 相似文献
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以凌海市水土保持示范园区的耕作土壤作为对象,研究不同治理措施对土壤理化性质的影响。结果表明:不同土地治理措施和作物共同影响着土壤物理性质;土地治理措施和人为因素对土壤养分含量有显著影响。根据试验结果可选择效果较好的治理措施,为凌海市水土流失防治提供依据。 相似文献
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土壤养分含量是土壤肥力的重要指标,是提高作物产量的重要物质基础,不过土壤养分含量受多种因素的影响,其影响的主要因素包括成土母质、成土过程、生物气候因素和施肥及农业利用方式,尤其是人类活动,对其含量产生直接的关系。本文通过对青河县16个沙棘地块的田间采样分析,以0～10cm、10～20cm、20～30cm、30～40cm... 相似文献
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随着机械化耕整地设备的快速普及,在生产效率提升的同时,也因连年重复性的耕整地和轮式机具对土壤产生的压实造成土壤退化和犁底层深厚问题.为有效改善传统耕整地作业造成的耕地土壤退化问题,打破耕地犁底层的不良影响,深松整地作业近年来得到了快速推广与应用.在玉米生产过程中,应用深松整地技术能有效改善玉米生长环境并提高玉米产量.从... 相似文献
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《Agricultural Systems》1999,59(2):193-214
Past explanations of why rural people respond as they do to external development interventions have emphasized the role of key limiting factors or critical characteristics (wealth, education, land tenure, etc.) which are thought to influence peoples' behavior in predictable ways. Efforts to promote tree planting and soil conservation in eight neighboring villages in the Philippines revealed that variation in participation did not reflect clear patterns based on existing household or village characteristics. Instead, specific responses to interventions reflected a complex, but interpretable interaction between existing socio-economic factors and historic trends or events. Characteristics like the degree of local knowledge, security of land tenure and community cohesion affected peoples' participation, in general, but their specific influence was neither predictable nor consistent between, and even within, individual villages. An appreciation of the specific historic context was often sufficient to explain these variations. The following historic trends and events were found to have important consequences for peoples' participation: migration and settlement history; family and group lineages; history of socio-political organization and conflict; history of physical isolation; labor history; economic–ecological history; environmental history; and past exposure to development agents. The paper concludes with a preliminary checklist of questions intended to assist researchers and development agents to discover relevant and interesting historical information about rural villages. 相似文献
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《Agricultural Water Management》2005,71(3):211-224
Using a Probit regression model, this study uses data from 230 small farm households in northern Burkina Faso to identify and analyse the determinants for the adoption of two soil and water conservation techniques, the “zaï” and the stone strip. The “zaï” is a traditional technique for restoring degraded soils by creating a micro-environment favourable for crops by digging and sowing in holes in which manure or compost has already been deposited. In the stone strips, stones are arranged perpendicular to the slope of the land in order to slow down water flow, encourage water infiltration and increase the sedimentation of the materials reconstituting soil.The Results indicate that the most significant variables for the adoption of both of these conservation adoption are training and small ruminants holding. Variables such as education and perception of soil degradation are determinants only for the adoption of zaï technique. Membership in a farmer's association and area cultivated are positively related only in the case of the stone strips. Although stone strips is a technique suitable for larger areas, the results show that the perception of soil degradation is not positively correlated with this technique. These findings suggest, therefore, that support services for rural development should focus their intervention on making farmers convinced of the problem of soil degradation before training them on soil conservation practices. 相似文献
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《Agricultural Systems》2005,85(1):59-81
Decision-making processes in agriculture often require reliable crop response models to assess the impact of specific land management. While process-based models are often preferred over empirical ones in current modelling communities, empirical crop growth models can play an important role in identifying the hidden structure of crop growth processes relating to a wide range of land management options. This study investigates the potential of predicting crop yield responses under varying soil and land management conditions by applying three different adaptive techniques: general linear models (GLMs), artificial neural networks (ANNs), and regression trees (RTs). The crop yield data used in this research consist of 720 maize yield indices from 11 different land management trials in southern Uganda. GLM showed the poorest results in terms of modelling accuracy, prediction accuracy, and model uncertainty, which might suggest its inability to model the non-linear causal relationships present in complex soil–land and crop-management interactions. The other two non-parametric adaptive models show significantly higher prediction accuracy than GLM. RT is the most robust technique for predicting crop yield at the study site. ANN is also a promising tool for predicting crop yield and offers insight into the causal relationships through the use of sensitivity analyses, but the complex parameterization and optimum model structure require further attention. The three adaptive techniques compared in this research showed different advantages and disadvantages. When these methods are used together, valuable information can be provided on crop responses, and more reliable crop growth models may result. 相似文献
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《Agricultural Water Management》2002,57(3):223-238
In the irrigated areas of semi-arid regions, especially in northwest India, a considerable recharge to the groundwater leads to waterlogging and secondary salinization. In several sub-areas groundwater is mined, water tables fall, and salts are added to the root zone because a high proportion of irrigation water is derived from pumped groundwater of poor quality. Out of 1 million hectares of irrigation induced waterlogged saline area in northwest India, approximately half a million hectares are in the state of Haryana. Taking a homogenous physical environment as a starting point, the way and the extent to which farmers’ activities will affect the salinity and sodicity situation depend on farming and irrigation practices. In the past, soil salinity was mainly associated with high groundwater tables, which bring salts into the root zone through capillary rise when water is pumped. But nowadays, increasing exploitation of groundwater for irrigation purposes has led to declining groundwater tables and a threat of sodification and salinization due to use of poor quality groundwater. Farmers in northwest India are facing a situation in which they have to deal with salt volumes that are harmful for water uptake of crops. They are also facing the problem of sodicity, which has an adverse effect on the physical structure of the soil, causing problems of water intake, transfer and aeration. To mitigate the adverse effect of soil salinity on crop yield, the farmers irrigate frequently, either mixing canal water and groundwater, or alternately using canal water and groundwater. Due to differences in environmental parameters in the farming systems, such as groundwater quality, soil types and uneven distribution of irrigation water, income losses to the farming community are not uniform. This paper highlights the economic loss due to environmental degradation through the twin problems of waterlogging and soil salinity, which threaten the sustainability of agricultural production in Haryana state. Our analysis shows that the net present value of the damage due to waterlogging and salinity in Haryana is about Rs. 23,900/ha (in 1998–1999 constant prices). The estimated potential annual loss is about Rs. 1669 million (about US$ 37 million) from the waterlogged saline area. The major finding of the paper is that intensification per se is not the root cause of land degradation, but rather the policy environment that encouraged inappropriate land use and injudicious input use, especially excessive irrigation. Trade policies, output price policies and input subsidies all have contributed to the degradation of agricultural land. 相似文献