An inventory of heavy metals inputs to agricultural soils in England and Wales

An inventory of heavy metal inputs (Zn, Cu, Ni, Pb, Cd, Cr, As and Hg) to agricultural soils in England and Wales in 2000 is presented, accounting for major sources including atmospheric deposition, sewage sludge, livestock manures, inorganic fertilisers and lime, agrochemicals, irrigation water, industrial by-product 'wastes' and composts. Across the whole agricultural land area, atmospheric deposition was the main source of most metals, ranging from 25 to 85% of total inputs. Livestock manures and sewage sludge were also important sources, responsible for an estimated 37-40 and 8-17% of total Zn and Cu inputs, respectively. However, at the individual field scale sewage sludge, livestock manures and industrial wastes could be the major source of many metals where these materials are applied. This work will assist in developing strategies for reducing heavy metal inputs to agricultural land and effectively targeting policies to protect soils from long-term heavy metal accumulation.     

Assessment of Doñana National Park contamination in Procambarus clarkii: Integration of conventional biomarkers and proteomic approaches

Aquatic ecosystems of Doñana National Park (DNP) were monitored using Procambarus clarkii as bioindicator in four campaigns carried out between 2003 and 2004 to assess environmental quality possibly threatened by agrochemicals used in nearby areas. An integrated approach was carried out, by combining the responses of well-established biomarkers and the massive analysis of biological effects at the proteomic level. In sites potentially polluted, lower catalase, glucose-6-P dehydrogenase, and esterase activities, and higher malondialdehyde, metallothionein and glutathione levels were found. Two-dimensional gel electrophoresis resolved > 2500 gill spots, and image analysis detected that 35 showed significant intensity differences between the reference site and the other seven sites studied. The superiority of proteomic approaches was clearly recognized in our study since four different protein expression patterns were established based in the fold-number of up-/down-regulation of the 35 differentially expressed proteins. Sites located within Doñana Biological Reserve were essentially free of contaminants and those near the DNP limits were only slightly polluted. The higher proteomic responses found at the upper “Rocina” and “Partido” courses indicate that non-persistent agrochemicals are mainly used in Doñana surroundings. The highest responses corresponded to rice growing areas placed between the Guadiamar stream and the Guadalquivir River, according to the extended and intensive use of agrochemicals in such areas.     

Relating nutrient and herbicide fate with landscape features and characteristics of 15 subwatersheds in the Choptank River watershed

Excess nutrients and agrochemicals from non-point sources contribute to water quality impairment in the Chesapeake Bay watershed and their loading rates are related to land use, agricultural practices, hydrology, and pollutant fate and transport processes. In this study, monthly baseflow stream samples from 15 agricultural subwatersheds of the Choptank River in Maryland USA (2005 to 2007) were characterized for nutrients, herbicides, and herbicide transformation products. High-resolution digital maps of land use and forested wetlands were derived from remote sensing imagery. Examination of landscape metrics and water quality data, partitioned according to hydrogeomorphic class, provided insight into the fate, delivery, and transport mechanisms associated with agricultural pollutants. Mean Nitrate-N concentrations (4.9 mg/L) were correlated positively with percent agriculture (R² = 0.56) and negatively with percent forest (R² = 0.60). Concentrations were greater (p = 0.0001) in the well-drained upland (WDU) hydrogeomorphic region than in poorly drained upland (PDU), reflecting increased denitrification and reduced agricultural land use intensity in the PDU landscape due to the prevalence of hydric soils. Atrazine and metolachlor concentrations (mean 0.29 μg/L and 0.19 μg/L) were also greater (p = 0.0001) in WDU subwatersheds than in PDU subwatersheds. Springtime herbicide concentrations exhibited a strong, positive correlation (R² = 0.90) with percent forest in the WDU subwatersheds but not in the PDU subwatersheds. In addition, forested riparian stream buffers in the WDU were more prevalent than in the PDU where forested patches are typically not located near streams, suggesting an alternative delivery mechanism whereby volatilized herbicides are captured by the riparian forest canopy and subsequently washed off during rainfall. Orthophosphate, CIAT (6-chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine), CEAT (6-chloro-N-ethyl-1,3,5-triazine-2,4-diamine), and MESA (2-[(2-ethyl-6-methylphenyl) (2-methoxy-1-methylethyl)amino]-2-oxoethanesulfonic acid) were also analyzed. These findings will assist efforts in targeting implementation of conservation practices to the most environmentally-critical areas within watersheds to achieve water quality improvements in a cost-effective manner.     

Ecologically and economically efficient and sustainable use of agricultural landscapes

Agricultural landscape use serves many purposes and many different people. For this reason, many public and private institutions are involved in the problem of optimal landscape use. In farms and rural family households basic decisions are taken on the intensity of agricultural landscape use. The decision-makers of these private institutions try to adapt optimally to the socio-economic framework. Public institutions play a key role in creating the socio-economic framework by policy-making. Thus, their members determine at least the use of agricultural landscapes and whether the use is ecologically and economically efficient and sustainable or not. To guide landscape use in an optimal direction, however, is a hard task for public decision-makers because nobody knows exactly what an ecologically and economically efficient and sustainable use of agricultural landscapes is. This problem results from unknown values, unknown interrelations between technology and nature, and unknown evolutionary processes in nature and in societies. Thus, there is a broad area for speculation about optimal landscape use. Such speculation, however, can be minimized by analysing options for action systematically. This is demonstrated in the case of an agricultural landscape in Southern Germany. In this case study, eight parts of a naturally homogeneous region are analysed by using multi-criteria valuation, linear programming and trade-off analyses. By combining these methods, the ecological and economical status quo of the uses of an agricultural landscape and possibilities for its improvement are evaluated to find out how the landscape can be used ecologically and economically in the most efficient way. Trade-offs representing a production frontier between the production of marketable and nonmarketable landscape goods are identified. With these findings, efficient agricultural policy options are revealed for the simultaneous achievement of ecological and economic efficiency and sustainability.     

Loss rates of urban biocides can exceed those of agricultural pesticides

Biocides and pesticides are used to control unwanted organisms in urban and agricultural areas. After application, they can be lost to surface waters and impair water quality. Several national consumption studies have shown that urban and agricultural use may be in the same range. It is difficult to judge whether this results in similar loadings of surface waters because there is a lack of sound, comparative studies addressing urban and agricultural losses simultaneously.The aim of this study is thus to relate the biocide and pesticide loads found in surface waters to their respective urban and agricultural usage (loss rates). To simultaneously assess the loss rates, we conducted a comprehensive field study in a catchment of mixed land use on the Swiss Plateau. The study area was divided into four sub-catchments with different degrees of urban and agricultural land use. In addition, we studied the only wastewater treatment plant, a combined sewer overflow and a storm sewer within the area. Rain events were sampled at high temporal resolution from March to November, 2007. Information on agricultural applications was gained from local farmers. For urban uses, consumption estimations were conducted based on statistical and product information.Despite substantially lower amounts used, the measured loads of urban biocides were in the same range as the most widely-used agricultural pesticides. The lower usage was compensated by urban loss rates that were up to ten times higher than agricultural ones (0.6 to 15% for urban, 0.4 to 0.9% for agricultural compounds). For most biocides and pesticides, the loads were controlled by rain events. Besides the rain-controlled losses, some urban-used biocides (e.g. diazinon) showed a continuous load independent of rain events and season. This study demonstrates that in catchments with mixed land use, mitigation strategies have to pay sufficient attention to the urban sources.     

Towards a faster and broader application of biochar: appropriate marketing mechanisms

Biochar derived from organic wastes and incorporated in soils offers multiple environmental and financial benefits. This approach tackles several critical global issues including waste management, renewable energy production, greenhouse gas mitigation, soil degradation prevention, food security, reduced water pollution from agrochemicals, and water quality and quantity enhancement. But farm level production and use of biochar is not yet viable, largely due to financial and technical constraints. Thus, an incentive mechanism for farmers is crucial for its successful adoption. This paper analyses both the current provisions and the marketing mechanisms of the Clean Development Mechanism (CDM), one of the three market‐based mechanisms of the Kyoto Protocol which links developed and developing countries in achieving global emission targets, and identifies appropriate marketing vehicle for biochar projects.     

村庄整合建设的两类依托——社会结构与资源利用方式

我国传统村庄聚落的建设,源于农耕社会的人群结构和农业资源的利用方式,家族式聚居与小农式生产方式为农耕社会中典型村庄建设的基础特征。当前在全国范围内,传统村庄正以每年近9万个的速度消失,标示出农耕社会村庄建设基础依托的失效。随着当代社会逐渐由工业向后工业和信息社会的转变,人群的社会结构和资源利用方式相较传统农耕社会发生了根本的改变,并导致当代的村庄建设突破原有的格局而发生整合更新。社会结构和资源利用方式作为村庄建设的两类依托基础,当代协作化的社会组织结构和规模化的农业生产方式,使得传统的"农耕型"村庄向当代的"农产型"村庄更新整合。     

由单一走向多样：平原农业区生物多样性 保护的规划途径——以辽宁省黑山县为例

平原农业区的生产和土地利用方式严重影响区域的生物多样性,利用融合多学科的景观空间规划构建有效的评价方法和格局优化模式以实现多样化的生境保护和恢复,提升生物多样性具有重要的作用。以辽宁省黑山县为例,首先梳理了平原农业区对于生物多样性威胁的机制和研究的框架;其次识别平原农业区的特殊生境类型,使用景观格局指数和In VEST模型的生境质量评价构建多尺度生境质量评价机制;同时使用基于图论和电路理论的LinkageMapper软件,识别和分级空间中的重要生态源地、潜在廊道及廊道上的关键夹点区域。结果显示,农业景观中空间异质性和连接性影响生物多样性;研究区有主要生境23类,整体生境质量较差,农田面积较大是造成该问题的主要原因;识别出核心斑块33个,重要廊道34条,通过与卫星图比照,廊道位置与线性生境重合;关键夹点区域位于靠近农村居民点的自然生境上,故营造人类干扰与生态平衡农村居住区是空间规划的重点;同时根据以上研究提出了多尺度的空间规划途径,为平原农业区生境优化和生物多样性保护提供了一定的理论参考。     

基于“三生”功能的柳州市国土空间适宜性评价

国土空间适宜性评价是空间规划的前提和基础。文章以国土资源现状为本底,从土地资源、水资源、生态、环境、气候、灾害和区位等资源环境要素角度构建评价指标体系,从资源本底和土地利用现状两方面分别对柳州市开展生态保护、农业生产及城镇建设适宜性评价,并将生态、农业和城镇综合评价结果在空间上进行叠加分析,逐块分析每个网格单元需要的生态保护、利于农业生产与适宜城镇开发建设的功能等级,确定各图斑单元的功能属性,划分形成以生态保护、农业发展和城镇开发为主导功能的三类国土空间格局。     

A multi-scale, multi-model approach for analyzing the future dynamics of European land use

Europe’s rural areas are expected to witness massive and rapid changes in land use due to changes in demography, global trade, technology and enlargement of the European Union. Changes in demand for agricultural products and agrarian production structure are likely to have a large impact on landscape quality and the value of natural areas. Most studies address these changes either from a macro-economic perspective focusing on changes in the agricultural sector or from a local perspective by analyzing recent changes in landscapes for small case studies. This paper describes a methodology in which a series of models has been used to link global level developments influencing land use to local level impacts. It is argued that such an approach is needed to properly address the processes at different scales that give rise to the land use dynamics in Europe. An extended version of the global economic model (GTAP) and an integrated assessment model (IMAGE) are used to calculate changes in demand for agricultural areas at the country level while a spatially explicit land use change model (CLUE-s) was used to translate these demands to land use patterns at 1 km² resolution. The global economic model ensures an appropriate treatment of macro-economic, demographic and technology developments and changes in agricultural and trade policies influencing the demand and supply for land use related products while the integrated assessment model accounts for changes in productivity as result of climate change and global land allocation. The land use change simulations at a high spatial resolution make use of country specific driving factors that influence the spatial patterns of land use, accounting for the spatial variation in the biophysical and socio-economic environment. Results indicate the large impact abandonment of agricultural land and urbanization may have on future European landscapes. Such results have the potential to support discussions on the future of the rural area and identify hot-spots of landscape change that need specific consideration. The high spatial and thematic resolution of the results allows the assessment of impacts of these changes on different environmental indicators, such as carbon sequestration and biodiversity. The global assessment allows, at the same time, to account for the tradeoffs between impacts in Europe and effects outside Europe.     

便携式GC-MS在石油污染土壤应急监测中的应用

目前,我国农业现代化建设与农村经济发展进入关键时期,设施农业用地备案监管问题突出。本文以设施农业用地备案监管工作为核心,通过分析设施农业用地备案监管工作需求,结合地理信息手段,通过搭建设施农业用地备案监管平台,科学辅助设施农业用地备案监管工作,科学引导设施农业用地选址和节约集约利用土地,更好地满足管理部门对设施农业用地进行日常监督管理、执法巡查、现场踏勘和用地审查的需求。     

Hotspots for Growth

Problem, research strategy, and findings: Our study contributes to the ongoing debate about the ability of Maryland's Priority Funding Area (PFA) program to control urban sprawl. We develop an economic-based land use conversion model to estimate if the PFA program steers urban growth to locations inside targeted growth areas within a fast-growing, exurban county. The results indicate that the size of an agricultural parcel, its distance from urban parcels, its proximity to highways, the productivity of agricultural land, and location in or outside PFAs influence the probability an agricultural parcel will be converted to urban use. We find that some of the parcels experiencing the greatest market pressure for development are located outside PFAs, and Maryland's incentive-based strategy is not completely effective at preventing sprawl.

Takeaway for practice: Careful design of the location of entrances and exits on and off highways, limitation of agricultural parcel fragmentation, and vigilant control of land use change in unproductive agricultural areas can limit sprawl. Our analysis highlights, yet again, the importance of communication between transportation and land use planners.

Research support: The research was supported by funding from the Harry R. Hughes Center for Agroecology, Inc.     

Using isopleth mapping to evaluate landslide activity in relation to agricultural practices

In comparison to urban or suburban areas, agricultural lands generally have a lower landslide risk. This does not necessarily reflect a lower degree of landslide hazard. The lower risk is more often due to the sparser population and lower property values of rural areas. Population and property values influence methods applicable to assessing landslide hazard in rural areas. The cost of data and size of areas over which assessments must be made for agricultural lands render many assessment procedures uneconomic. Their use is only justified in populous, high-value areas. Many agricultural practices may have the same potential for initiating landslide activity recognized for some land uses in urban areas. Like their urban counterparts, residents dependant onagriculture for their livelihood suffer from the consequences of landslides. For these reasons, a method for landslide hazard assessment suitable for rural areas is needed. This need is satisfied by isopleth mapping of landslides. Isopleth mapping provides an economical means for assessing the degree of landslide hazard present within a large area. Data needs are limited to topographic and landslide maps. Isopleth maps facilitate comparison of landslide data to other information for developing a better understanding of how agricultural practices affect landslide activity. Their use in the Tuscany region of Italy provide insight on how changing agricultural practices altered landslide activity. Isopleth maps serve as a simple way to accomplish landslide hazard zonation. Landslide hazard zonation identifies locations where land use controls should be applied to achieve hazard reduction. Hazard reduction based on isopleth mapping is illustrated by their use in timber sale planning in California, USA.     

Delineating cost‐effective wellhead protection zones in a rural area in Greece

The aim of this study is the protection of groundwater resources from nitrate pollution by regulating land use and by establishing guidelines for agricultural activities within specific wellhead protection areas. Wellhead protection zones are specifically designed in four wells in the municipality of Nea Moudania, an area of intensive agricultural activities in northern Greece. Recent water samples from these wells indicate high levels of nitrates concentrations. Wellhead protection areas are delineated through a geographic information systems (GIS) analysis in order to determine the boundaries of protection zones, as well as to identify the land use patterns and the specific crop types around the contaminated wells. Different land use management techniques for groundwater protection zoning are also examined with respect to their implementation cost. The purpose of this analysis is to identify the least expensive management strategy for wellhead protection. The results show that land use changes are always more expensive than implementing agro‐environmental measures.     

农业景观信息探研——以四库本王祯《农书》为例

元代王祯《农书》是中国重要农业典籍,其四库本相对于其他版本图像信息更为全面丰富,生动地记录了传统农具及相关生产技术状况,并反映出了当时的农业景观信息。选用《农书·农器图谱》中人、物、环境信息相对全面翔实的图像作为主要研究依据,对其进行分类与总结,描绘并探讨土地利用、农田水利、农作物种植、农村生活等方面的景观信息,再现古朴宁静的田园风貌,并由此揭示古人在农业活动中的技术发明和农业景观形态。这不仅可以促进农业文化遗产价值的挖掘,也对当今的传统村落保护和乡村景观建设带来一定的思考和启发。     

The economic impact of restricted water supply: a computable general equilibrium analysis

Water problems are typically studied at the level of the river catchment. About 70% of all water is used for agriculture, and agricultural products are traded internationally. A full understanding of water use is impossible without understanding the international market for food and related products, such as textiles. The water embedded in commodities is called virtual water. Based on a general equilibrium model, we offer a method for investigating the role of water resources and water scarcity in the context of international trade. We run five alternative scenarios, analyzing the effects of water scarcity due to reduced availability of groundwater. This can be a consequence of physical constraints, and of policies curbing water demand. Four scenarios are based on a "market solution", where water owners can capitalize their water rent or taxes are recycled. In the fifth "non-market" scenario, this is not the case; supply restrictions imply productivity losses. Restrictions in water supply would shift trade patterns of agriculture and virtual water. These shifts are larger if the restriction is larger, and if the use of water in production is more rigid. Welfare losses are substantially larger in the non-market situation. Water-constrained agricultural producers lose, but unconstrained agricultural produces gain; industry gains as well. As a result, there are regional winners and losers from water supply constraints. Because of the current distortions of agricultural markets, water supply constraints could improve allocative efficiency; this welfare gain may more than offset the welfare losses due to the resource constraint.     

Examples of Recent Models in Environmental Impact Assessment

Models are being used extensively to study the impact on the environment of a wide range of man-made influences. These include land-use change (e.g. afforestation), effluent discharges, flood-relief channels, reservoir developments, atmospheric pollution and the impacts of agrochemicals. In this paper several models are described which are being used by the Institute of Hydrology for environmental impact assessment. These models include MAGIC (Model of Acidification of Groundwater in Catchments), QUASAR (Quality Simulation Along Rivers) and a nitrogen simulation model for investigating the behaviour of nitrate in reservoirs.     

Alternatives to pesticides in Southeastern United States

A critical review of alternatives to the use of pesticides in agricultural practice in the Southeastern United States is presented. The methods, their stage of development and case histories are cited.     

废弃农膜对环境的污染防治及检测研究

我国全年地膜使用量达到几十万吨。废弃农膜如果不及时处理,对于环境可能造成严重的污染。分析废弃农膜对土壤环境的污染,提出防治污染的有效对策,对废弃农膜残留进行检测分析并实施科学管理,将会降低可能产生土壤污染问题,提升废弃农膜的综合再利用水平。     

Interdisciplinary Analysis of Hedgerow Network Landscapes' Sustainability

Hedgerows with pollarded trees are still emblematically shaping many agricultural landscapes in Western Europe; they are part of our heritage but their future is uncertain due to the enlargement of fields and loss of firewood use. As a consequence the sustainability of these agricultural landscapes is questioned. We studied changes in hedgerow management in a long-term ecological site in Brittany, France with an interdisciplinary approach. Importance, spatial distribution and relationship with the agricultural system have been assessed over 11 years in three contrasted hedgerow network landscapes, while management practices and farmers' perception were studied from an anthropological point of view. Two apparently opposed trends were found: first, an apparent decrease in the interest of farmers for hedgerows witnessed by the diminishing of the rate of pruning; second, changing attitudes of farmers not necessarily toward hedgerow abandonment but rather toward the production of novel shapes for pruned trees.