The Moral Economy of Water: Equity and Antiquity in the Andean Commons

This article focuses on irrigation and water use in a community in the Peruvian Andes, one of numerous villages in the region where these activities are carried out in an unusual way. The practices and principles that make up this tradition, defining the rights and duties of community members in making use of the resource most vital for life, are identified and evaluated based on comparative ethnographic research. It is argued that they provide a highly effective way of managing a scarce and fluctuating resource that is held in common, an older Andean tradition that may have been adopted by the Incas and endorsed as an official policy—all of which might help to account for its wide distribution in the region today. In this particular case, the principles help to create an extraordinary kind of community, a transparent and equitable one in which a basic material symmetry or proportionality is expressed at many levels. This symmetry is closely related to other basic commonalities among community members, but of particular interest are its effects on social solidarity and cooperation and its association with a strong sense of ethnic identity. The implications of this tradition for solving contemporary problems in water management are also briefly discussed, [sociocultural anthropology, irrigation, Andes, common-property]     

Deficit Irrigation as a Strategy to Save Water： Physiology and Potential Application to Horticulture

Water is an increasingly scarce resource worldwide and irrigated agriculture remains one of the largest and most inefficient users of this resource. Low water use efficiency （WUE） together with an increased competition for water resources with other sectors （e.g. tourism or industry） are forcing growers to adopt new irrigation and cultivation practices that use water more judiciously. In areas with dry and hot climates, drip irrigation and protected cultivation have improved WUE mainly by reducing runoff and evapotranspiration losses. However, complementary approaches are still needed to increase WUE in irrigated agriculture. Deficit irrigation strategies like regulated deficit irrigation or partial root drying have emerged as potential ways to increase water savings in agriculture by allowing crops to withstand mild water stress with no or only marginal decreases of yield and quality. Grapevine and several fruit tree crops seem to be well adapted to deficit irrigation, but other crops like vegetables tend not to cope so well due to losses in yield and quality. This paper aims at providing an overview of the physiological basis of deficit irrigation strategies and their potential for horticulture by describing the major consequences of their use to vegetative growth, yield and quality of different crops （fruits, vegetables and ornamentals）.     

水与村落关系的生态学思考

村落是地表突出且普遍的景观。从生态学角度而言 ,村落系以农村人群为中心 ,伴生生物为主要生物群落 ,建筑设施为重要栖息环境的人工生态系统。村落具有景观、分布、结构、功能、生命过程、新陈代谢和分类区划等生态学特征。从生态学角度对村落生态系统进行研究 ,形成具有特色的生态学分支村落生态学 (ｖｉｌｌａｇｅｅｃｏｌｏｇｙ) ,村落生态学具有确定性定义和研究内容[1 ] 。我国是一个农业大国 ,目前全国分布有 5 0 0多万个村落 ,6万多个集镇 ,市镇人口约占 30 % ,农村人口约占 70 % ,是农村生态系统的重要组成部分。我国 5 5个少数民…     

Deficit Irrigation as a Strategy to Save Water: Physiology and Potential Application to Horticulture

Water is an increasingly scarce resource worldwide and irrigated agriculture remains one of the largest and most inefficient users of this resource. Low water use efficiency (WUE) together with an increased competition for water resources with other sectors (e.g. tourism or industry) are forcing growers to adopt new irrigation and cultivation practices that use water more judiciously. In areas with dry and hot climates, drip irrigation and protected cultivation have improved WUE mainly by reducing runoff and evapotranspiration losses. However, complementary approaches are still needed to increase WUE in irrigated agriculture. Deficit irrigation strategies like regulated deficit irrigation or partial root drying have emerged as potential ways to increase water savings in agriculture by allowing crops to withstand mild water stress with no or only marginal decreases of yield and quality. Grapevine and several fruit tree crops seem to be well adapted to deficit irrigation,but other crops like vegetables tend not to cope so well due to losses in yield and quality. This paper aims at providing an overview of the physiological basis of deficit irrigation strategies and their potential for horticulture by describing the major consequences of their use to vegetative growth, yield and quality of different crops (fruits, vegetables and ornamentals).     

A county‐level estimation of renewable surface water and groundwater availability associated with potential large‐scale bioenergy feedstock production scenarios in the United States

This study examines fresh renewable water resources available for bioenergy feedstock production in the United States. The impacts of feedstock irrigation on surface and groundwater resources available to nonbioenergy sectors were quantified using a pair of water availability indexes: streamflow availability index and percolation flow availability index. The two metrics were applied to both historical (2008) and three possible future biomass production scenarios from the 2016 U.S. Billion‐Ton Report at the county level. For both historical and future scenarios, we found that the consumptive irrigation requirements for bioenergy feedstock account for <0.01% of annual streamflow in all but three counties in Nebraska. Results suggest that the irrigation demand of future biomass production could be supplied by annual renewable groundwater flow in about 94% of feedstock‐growing counties that use groundwater for irrigation, representing about 92% of production tonnage. Counties that require irrigation from nonrenewable groundwater resources are mostly located in the Northern Plains and Pacific regions. We also evaluated the sensitivity of crop water footprint estimation to soil moisture carryover by comparing blue water estimates from six different empirical and process‐based methods. Our findings suggest that accounting for preseason soil moisture is critical for representative blue water estimation, so that the irrigation water consumption is not overestimated. This is especially true in the Corn Belt region, where blue water estimates with and without preseason soil moisture would be about 1.9 versus 45.5 billion m³/year under the historical scenario. This difference is smaller in semiarid regions like the High Plains, but the blue water estimate can still triple if soil moisture is not considered. From the perspective of renewable surface water and groundwater resources, scaling feedstock production up in the High Plains and California will require careful planning integrated with water management strategies to improve water resource conservation.     

亏缺灌溉对棉花生长和水分利用效率的影响研究进展

棉花是世界上最主要的农作物之一。随着全球水资源的日益紧张,灌溉用水将成为限制棉花生产的主要因素。亏缺灌溉是一种低于作物正常腾发量的灌溉方式,可以在保证棉花产量和品质的前提下提高水分利用效率,是一种有效的节水灌溉方式。本文综述了亏缺灌溉对棉花生长和水分利用效率的影响。亏缺灌溉可以通过促进棉花由营养生长向生殖生长转化,降低棉花株高、叶面积、总生物量,从而提高收获指数、茎粗和水分利用效率。最后,综合现有的研究,结合棉花生产实际,提出亏缺灌溉应用推广建议,以期为旱区棉花可持续发展提供理论指导。     

Breeding of Anopheles mosquitoes in irrigated areas of South Punjab, Pakistan

As part of investigations on potential linkages between irrigation and malaria transmission, all surface water bodies in and around three villages along an irrigation distributary in South Punjab, Pakistan, were surveyed for anopheline mosquito larvae (Diptera: Culicidae) from April 1999 to March 2000. Samples were characterized according to exposure to sunlight, substratum, presence of vegetation, fauna, inorganic matter and physical water condition (clear/turbid/foul). Also water temperature, dissolved oxygen (DO), electroconductivity (EC) and pH of sites were recorded. A total of 37982 Anopheles larvae of six morphological types were collected from 2992 samples taken from irrigation/agricultural and village/domestic aquatic habitats. Anopheles subpictus Grassi sensu lato was by far the most abundant (74.3%), followed by An. culicifacies Giles s.l. (4.1%), An. stephensi Liston s.l. (2.6%), An. pulcherrimus Theobald (1.8%), An. peditaeniatus Leicester (0.3%) and An. nigerrimus Giles (0.1%). The four most abundant species were significantly associated with waterlogged fields and communal village drinking-water tanks. Habitat characteristics most correlated with occurrence of anophelines were the physical water condition and the absence/presence of fauna, particularly predators. Occurrence and abundance of Anopheles immatures were not significantly correlated with water temperature, DO, EC or pH. Malaria vectors of the Anopheles culicifacies complex occurred at relatively low densities, mainly in irrigated and waterlogged fields. In South Punjab, where rainfall is very low, it should be possible to reduce anopheline breeding through water management, as larvae develop mainly in water bodies that are directly or indirectly related to the extensive canal-irrigation system.     

Water-Saving and High-Yielding Irrigation for Lowland Rice by Controlling Limiting Values of Soil Water Potential

The present study investigated whether an irrigation system could be established to save water and increase grain yield to enhance water productivity by proper water management at the field level in irrigated lowland rice （Oryza sativa L.）. Using two field-grown rice cultivars, two irrigation systems; conventional irrigation and water-saving irrigation, were conducted. In the water-saving irrigation system, limiting values of soil water potential related to specific growth stages were proposed as irrigation indices. Compared with conventional irrigation where drainage was in mid-season and flooded at other times, the water-saving irrigation increased grain yield by 7.4% to 11.3%, reduced irrigation water by 24.5% to 29.2%, and increased water productivity （grain yield per cubic meter of irrigation water） by 43.1% to 50.3%. The water-saving irrigation significantly increased harvest index, improved milling and appearance qualities, elevated zeatin-I-zeaUn riboside concentrations in root bleedings and enhanced activities of sucrose synthase, adenosine diphosphate glucose pyrophosphorylase, starch synthase and starch branching enzyme in grains. Our results indicate that water-saving irrigation by controlling limiting values of soil water potential related to specific growth stages can enhance physiological activities of roots and grains, reduce water input, and increase grain yield.     

水肥一体化技术在海南干热香蕉种植区的应用

海南为我国栽培香蕉的主产区之一,西南部干热地区（昌江、东方、乐东、三亚）是海南省目前发展香蕉规模最大的区域,也是中国规模化反季节香蕉生产的主要基地之一。由于位处干热气候影响下的半干燥区,干旱较严重,加上施肥欠合理,对香蕉产业的可持续发展影响极大。发展节水灌溉是解决海南干热地区干旱缺水的必由之路,应用水肥一体化技术对香蕉实施节水灌溉, 根据作物需要进行施肥,在保证香蕉的产量和质量的前提下,实现节水、省肥、节省人工之效,从而达到产业增效目的。     

Temporal Persistence of Resource Polymorphism in Brook Charr, Salvelinus Fontinalis

Resource polymorphisms are believed to be an important intermediate step in competitive sympatric speciation. Reports of resource polymorphisms in fishes are becoming more common, but tests of the temporal persistence of resource polymorphisms remain scarce. We examined the temporal persistence of a body shape dimorphism reported previously for stream dwelling young-of-the-year brook charr, Salvelinus fontinalis, inhabiting slow vs. fast running water. In the year of our study, we found no difference in body shape between individuals in slow vs. fast flowing water, although fish in fast flowing water were of greater standard length than those in slower flowing water. We conclude that the resource polymorphism reported earlier for brook charr in streams is not stable temporally.     

华北冬小麦降水亏缺变化特征及气候影响因素分析

为了探究气候变化背景下作物降水亏缺变化规律和影响因素,该文基于华北地区1971－1980年和2001－2010年气象数据和冬小麦生育期资料,研究了冬小麦生育期内降水亏缺变化特点,利用构建的敏感度分析模型探讨了降水亏缺量对主要气候要素的敏感性特征,主要结论：2001－2010年华北中部地区冬小麦全生育期内干旱加重,降水亏缺面积略有增加;播种—返青期内降水亏缺程度自江苏徐州—河南许昌一线往北都有所加剧,返青—拔节期内降水亏缺程度缓解,拔节—抽穗期内降水亏缺程度加重,仅在山西中部太原地区降水略有盈余,抽穗—成熟期内降水亏缺有所缓解;冬小麦拔节—抽穗期降水亏缺量对日照时数高度正向敏感站点最多,主要分布在河北北部地区和安徽省,其次是风速,对温度和降水的高度正向敏感站点最少。该文为制定灌溉定额,农业水资源管理和缓解水资源供需矛盾提供科学依据。     

Much Improved Irrigation Use Efficiency in an Intensive Wheat-Maize Double Cropping System in the North China Plain

Crop yield and water use efficiency （WUE） in a wheat-maize double cropping system are influenced by short and uneven rainfalls in the North China Plain （NCP）, A 2-year experiment was conducted to investigate the effects of irrigation on soil water balance, crop yield and WUE to improve irrigation use efficiency in the cropping system, Soil water depletion （~SWS） by crop generally decreased with the increase of irrigation and rainfall, while ASWS for the whole rotation was relatively stable among these irrigation treatments, High irrigations in wheat season increased initial soil moisture and ASWS for subsequent maize especially in the drought season, Initial soil water influenced mainly by the irrigation and rainfall in the previous crop season, is essential to high yield in such cropping systems, Grain yield decreased prior to evapotranspiraUon （ET） when ET reached about 300mm for wheat, while maize showed various WUEs with similar seasonal ET, For whole rotation, WUE declined when ET exceeded about 650 mm, These results indicate great potential for improving irrigation use efficiency in such wheat-maize cropping system in the NCP, Based on the present results, reasonable irrigation schedules according to different annual rainfall conditions are presented for such a cropping system.     

根系分区灌溉和水分利用效率

根系分区灌溉是指仅仅部分根系受到正常的灌溉,其余根系则受到人为的干旱,两项理论根据指出这种措施可减少植物的水分肖耗,并保持一定的生物产量,其一是植物蒸腾失水与气孔导性是线性关系,而光合作用与气孔导性则是一种渐趋饱和的关系,如果气孔导性从最大值适应调低,可显著降低蒸腾,但对光合影响应小得多,其二是处于干燥土壤中的根系可感觉干旱,产生干旱信号来调节地上部分的气孔开度,显然,这项措施在田间有多大效用值得深入研究。 先是大田作物的蒸腾失水仅部分地受气孔控制,界面层的扩散阻力起很大作用。因此该措施可能对界面层阻力较小的,如果树等作用大些,另外,根系干旱信号可否“长期”地产生和调控气孔仍需试验证明。     

地表水资源供给服务供需关系对节水政策的响应——以大清河流域为例

水资源是基础性自然资源和战略资源,科学量化水资源供给服务的供需关系、识别供需矛盾的突出区域是进行流域水资源管理的重要前提。以大清河流域为例,利用InVEST模型,建立了水资源供给服务空间流动量化方法,预测了用水效率提升、节水灌溉两种节水政策情景对水资源供给服务供需关系的影响。结果表明：(1)流域水资源供给服务和水资源需求量均呈现出上游低、下游高的空间分布格局,农业用水为流域主要用水类型,2010—2015年,流域水资源供给服务增长0.97%,水资源需求量出现了9.6%的下降;(2)2010—2015年,流域整体水资源供给服务的供需比由0.78提升至0.88,服务的空间流动使得上游盈余的水量缓解了中下游的用水压力,但中下游水资源需求大于供给的问题仍普遍存在;(3)提升用水效率、推行节水灌溉这两种节水政策均能够有效改善大清河流域的水资源供需关系,分别可将流域水资源供需比提升至0.97和0.96,基本达到供需平衡。研究可为北方资源型缺水流域水资源供需匹配度的提高、节水政策潜力的评估提供借鉴。     

Contested value and an ethics of resources: Water,mining and indigenous people in the Atacama Desert,Chile

The question of value is fundamental to contexts of resource scarcity given that contest over use and distribution of scarce resources centres on judgments about rights, interests and access. In mining processes, the use and extraction of water in great volumes commodifies and threatens supplies of what others understand to be a substance essential to all forms of life. In the Atacama, while industrial extraction and commodification by the mining industry are the basis for indigenous people's contestations over water resources, an analysis of everyday water practice and performance (as ‘ordinary ethics’) demonstrates that an indigenous ethics of resources includes commodity values under certain conditions. This paper examines a field of competing actors engaging in extraction and use of scarce waters in order to make an argument for the importance of considering the complexities and dynamics of ethical practice and water value.     

民勤湖区地下水资源时空变化对灌区景观生态安全的影响研究

以生态安全面临着严重威胁的我国干旱区民勤绿洲湖区灌区景观为例,研究地下水资源的时空变化对灌区生态安全的影响．利用GIS进行地下水的空间插值得到地下水埋深与地下水矿化度的时空变化．结果表明,地下水埋深在14年间持续下降,且灌区中心地带的地下水埋深的下降速率较边缘地带快。导致地下水降落漏斗不断加深,并逐渐由灌区中心向边缘扩展．大于3m的地下水埋深面积比例逐年增加,由1987年占湖区总面积的81．2％上升到2001年的97．4％．地下水埋深的持续下降导致土壤含水量降低是除人为破坏而引起林木自然衰败、死亡,并引起灌区自然生态安全水平降低的主要原因．当地下水埋深超过8m,地下2m处土壤含水率达到12％以下,大部分乔木林枯梢率达到90％以上,而灌木林枯梢率也达到50％以上．受地下水位下降的影响,14年间有林地、灌木林地与疏林地的斑块面积分别减少了67％、54％与31％,斑块数量减少35、42与50块．地下水矿化度的上升导致作物的安全生长格局发生显著变化,导致农业经济效益降低、种植业结构调整受到严重制约,构成对灌区经济生态安全的严重影响．合理分配流域中、下游水资源量,限制人类不合理的土地利用方式,减少灌区耕地面积,构建安全的景观格局．逐渐恢复地下水采、补平衡,阻止地下水位的进一步下降与地下水矿化度的上升是提高灌区生态安全水平的重要途径．     

Agricultural resource use in an andean coastal ecosystem

Five concurrent systems of agricultural resource management in the Viru Valley in Peru's arid northern coastal plain are discussed as adjustments to microenvironmental variations in soil humidity. Widespread dependence on canal irrigation in an environment characterized by uncertainty in the availability of river water affects the agrarian population in several ways. The upper socioeconomic class has adapted to uncertainty by implementing a deviation-counteracting mechanism (tubular wells) that provides water on demand, giving them flexibility in choice of agricultural activities. Another class of farmers is unable to introduce this mechanism, however, and consequently must depend on a repertoire of inflexible decisions to cope with uncertainty. Each group exploits different opportunity costs to increase economic gain. One pattern provides for expansion, whereas the other at best establishes stability and maintenance. Noncanal techniques permit expansion of cultivation in conditions where canal irrigation is not feasible, thereby improving the overall level of effectiveness of resource use. Alternative techniques do not involve regulatory mechanisms nor do they require complex, interlocking social, economic, and political components. Their presence and persistence in the agricultural system provide variation that may ultimately be amplified as the need to intensify resource exploitation increases in the future.     

中水浇灌对3种绿地植物若干生理指标的影响

中水灌溉是缓解城市供水紧张和减少污水排放量的有效措施。通过短期盆栽试验和长期大田调查相结合的方法,以清水灌溉为对照;选用绿地植物台湾草、金叶假连翘和黄金榕为研究对象;以植物叶片中超氧化物歧化酶、过氧化物酶活性、丙二醛、脯氨酸含量、总叶绿素含量和叶片细胞膜透性6个生理指标作为评价。结果表明,在短期盆栽试验中,中水灌溉的三种植物叶片中总绿素含量显著高于对照,中水灌溉的台湾草叶片中的超氧化物歧化酶活性显著高于对照,其余指标差异不显著;长期大田调查的三种植物的6种指标在中水灌溉下与对照之间差异均不显著。     

微咸水滴灌对土壤酶活性、CO2通量及有机碳降解的影响

利用微咸水灌溉是解决干旱区水资源短缺的重要途径.通过田间小区滴灌试验,研究了不同矿化度微咸水(0.31、3.0、5.0 g·L^-1,NaCl浓度)对土壤过氧化氢酶、蔗糖酶、多酚氧化酶、β-葡萄糖苷酶和纤维素酶活性的影响,采用土壤碳通量和物料袋法研究了土壤CO₂通量和有机碳降解对微咸水滴灌的响应.结果表明: 微咸水(3.0 g·L^-1)处理下蔗糖酶、β-葡萄糖苷酶、纤维素酶的活性分别比淡水处理降低31.7%～32.4%、29.7%～31.6%、20.8%～24.3%,而土壤多酚氧化酶活性则随灌溉水矿化度提高而显著升高,在膜下微咸水、咸水处理多酚氧化酶较淡水处理提高2.4%、20.5%.土壤微生物生物量碳和微生物熵均随灌溉水矿化度提高呈降低趋势,而代谢熵则呈升高趋势.不同处理对土壤CO₂通量影响表现为淡水＞微咸水≥咸水,且膜下CO₂通量显著高于膜间(P<0.05),棉花吐絮期(9月20日)膜下淡水处理较咸水和微咸水处理的CO₂通量分别升高29.8%、28.2%,微咸水滴灌显著降低了土壤CO₂通量.不同矿化度微咸水滴灌对有机物(棉花和苜蓿秸秆)的降解率表现为淡水＞微咸水＞咸水,膜下有机物降解显著高于膜间.在培养第125天时,咸水、微咸水、淡水处理的膜间棉花秸秆回收率分别为39.7%、36.3%、30.5%,膜间苜蓿秸秆回收率分别为46.5%、36.5%、35.4%.微咸水灌溉明显抑制了北疆滴灌棉田土壤酶活性,造成土壤微生物量和CO₂通量下降,土壤有机物降解率降低,使绿洲农田土壤生物性状变差.     

高水位区暗管埋设下土壤盐分适时立体调控的生态效应

高水位地区作物生长关键期采用微咸水或咸水灌溉被证明在一定条件下可以起到增产正效应,但同时却存在着土体盐分积累及其对下茬或次年种植影响的生态负效应.为探讨消除或抑制微咸水或咸水灌溉对土壤盐分积累的生态负效应,保证作物种植增产的正效应,本文在河北近滨海高水位盐碱区开展了为期2年的试验研究,探讨了旱季微咸水或咸水灌溉带来的盐分异位积累与离子分布变化特征,分析了雨季关键期暗管适时排盐对土壤盐分的立体调控生态效应.结果表明：旱季咸水灌溉后土壤经历“积盐-脱盐-二次积盐”3个阶段;灌溉初期,1 g·L^-1咸水灌溉处理下0～50 cm土体脱盐,土壤含盐量随土壤深度增加而增加,HCO₃^-含量增加,其他离子含量降低;6与13 g·L^-1咸水灌溉处理下0～50 cm土体积盐,土壤含盐量随土壤深度增加而降低,HCO₃^-含量降低,其他离子含量增加;雨季暗管适时立体调控脱盐效果显著,土壤脱盐率达16.0%～45.7%,同降雨量下,降水分布越集中,脱盐效果越好;周年时间尺度上,咸水灌溉小区土壤积盐量小于对照区;咸水灌溉处理小区冬小麦产量显著高于对照处理,1 g·L^-1 处理高于6与13 g·L^-1处理.