How Viable will the Agricultural economy be in the New State of Palestine?

A key objective of the Israeli occupation of the West Bank and Gaza Strip in Palestine has been to render the economy of these regions dependent on the Israeli economy and thus hamper their economic development. Large areas of land have been confiscated or expropriated by the Israeli authorities to establish Jewish settlements. Other severe measures imposed include control of irrigation water and obstacles for the Arab agricultural and industrial sector in the Occupied Territories aimed at preventing Arab competition with Israeli products.Palestinian agriculturalists have met this challenge and have worked to achieve higher production levels in agriculture. Nonetheless, economic development there was blocked, and many agriculturalists sought employment inside Israel. The Intifada since December 1987 has aimed at encouraging Arab economic independence and intensification of efforts to meet national requirements of greater self-sufficiency in subsistence crops and stimulation of agriculture-related industries. The Intifada is thus functioning as a stimulus to development and economic viability.     

Desalination,space and power: The ramifications of Israel’s changing water geography

Desalination alters a basic premise of water geography – fresh water flows from the sea inward, rather than the other way around. But, is this observation important? To address this question it is necessary to identify the potential ramifications of the changes in the water geography brought about by desalination. Israel is used as a basis for identifying these ramifications as it has recently embarked on a large-scale desalination program. The direct readily observable implications of the three main attributes of desalination, the reversal of flow direction, the continuity of water production, regardless of weather and climate vagrancies, and its cost are first spelled out. Then the potential ramifications for internal power structures, pricing and transboundary water agreements are discussed for the Israeli and Israeli–Arab scene. It is shown that the spatial flexibility introduced by desalination may undermine existing power relations within the water sector, which were based on the previous water geography. In the Israeli case these changes may be used to undermine the monopoly power of the national water company and of its organized labor, thereby advancing a neoliberal agenda. Desalination may have also significant distributional implications, as a function of the pricing effects it may have. Finally, the new water geography raises new issues in the Israeli–Arab water scene. The general insights gained from the Israeli case are then spelled out.     

有咸水区深层淡水可持续利用研究

天津市东丽区第四系Ⅱ组深层淡水在长期较强开采状态下未发生水位持续下降及大面积深层淡水成化污染,十余年来地层沉降基本消失.该地多年来中更新统淡水及上更新统、全新统咸水水位具有同步不等幅的动态,证明它们之间联系密切,地层中渗透系数小于10-3m/d的历次海侵沉积层及压实的粘土层具有半透膜特性,咸水越流补给第Ⅱ承压含水组的是淡水.适量加大Ⅱ组淡水开采强度,使其产生越流系统,稳定后不会再加大地面沉降.最终使全新统地下水下入渗水位降低,夺取潜水蒸发的水量.在有咸水分布区,地表入渗水是尚没有引起足够重视的可持续利用地下淡水的补给来源.     

济南市设施农用地发展现状与对策建议

随着我国农业现代化发展,传统农业逐步向现代农业转变,尤其是近年来农村土地承包经营权流转进程加快,农业生产经营规模不断扩大,农业设施快速增加,势必要占用大量的农用地。因此,为适应现代农业发展需求,必须加强和完善设施农用地管理,防止以发展设施农业为名,滥占乱用土地,促进耕地保护和设施农业的健康有序发展。     

水资源合理调控利用发展农业节水灌溉

南皮县淡水资源短缺,咸水广布,制约农业生产的可持续发展.解决途径是合理调控利用当地水资源,开发利用浅层地下水包括微咸水和半咸水抗旱灌溉,调蓄雨季降雨径流及汛后河流来水作为补源,地下水地上水联合运用,发展农业节水灌溉,调整农业种植结构,提高水的利用效率.实现水资源可持续利用,农业生产可持续发展,生态环境良性循环,人与自然和谐相处.     

Revolution or evolution? New Zealand agriculture since 1984

Agriculture was the primary target of moves to deregulate the New Zealand economy in 1984. Within twelve-months all production subsidies had been removed, including those for fertiliser and other inputs, as well as funding for drought relief, floods and other natural weather disasters. Whereas at the start of 1984, subsidies were estimated to represent as much as 33% of farm income, by 2003 this had fallen to less than 2% with most of this spent on agricultural research. The anticipated shift of thousands of people off the land did not appear to occur, and by conventional measures at least New Zealand agriculture in 2003 is a major success story. At the core of the changes imposed on agriculture was a commitment to remove all state or government distortions from the system and to fully expose the agricultural sector to market forces. This included wide-ranging and fundamental changes in the broad institutional context within which agriculture must operate. All this was achieved at great social cost and with a significant impact on the environment. In many respects New Zealand agriculture is now very different from that in 1984. Some sectors, such as dairying, have grown and become increasingly industrialised. On the other hand, sheep farming, particularly for wool has struggled to maintain its market share, while other enterprises have emerged as significant sources of income, including horticulture, viticulture and fruit. It is argued here that the trends evident in New Zealand agriculture since 1984 pre-existed the reform period and that the apparent success of the reforms evident at a national scale have not addressed or removed the fundamental problems which face New Zealand agriculture, just as they do modern agricultural systems elsewhere. This revised version was published online in July 2006 with corrections to the Cover Date.     

Hydrochemical evolution and variation of groundwater and its environmental impact at Sohag, Egypt

Groundwater resources of Sohag, Egypt are currently threatened by contamination from agricultural and urbanization activities. Groundwater in Sohag area has a special significance where it is the second source for fresh water used for agricultural, domestic, and industrial purposes. Due to growing population, agriculture expansion, and urbanization, groundwater quality assessment needs more attention to cope with the increasing water demand in this arid zones and limited water resources. The aim of this paper is to address the integrated role of geochemical processes, agriculture and urbanization in evolution of groundwater composition, and their impact on groundwater quality to help in management and protection of groundwater resources of study area using geochemical modeling techniques and geographical information systems. Spatial variation of groundwater hydrochemical properties, rock–water interaction, ion exchange, and assessment of groundwater quality were investigated. Results indicated that groundwater properties are varied spatially and its evolution in the study area is generally controlled by the prevailed geochemical processes represented by leaching, dissolution, and precipitation of salts and minerals, ion exchange, in addition to human activities represented by agriculture and urbanization as well as climatic and poor drainage conditions. Management alternatives should be followed in the study area to avoid degradation of groundwater quality and provide sustainable development.     

松嫩平原农业水资源优化管理模型

松嫩平原是我国重要的商品粮生产基地，水资源短缺和不合理利用严重制约着农业的可持续发展。研究中选择国家“九五”农业重点科技攻关吉林省大安试验作为研究区，针对农业发展状况和目标、次生盐碱化形成机理和水资源开发利用现状及其存在的问题等多种自然和人为条件，建立区域农业水资源优化管理模型，确定水资源最优利用方案，为农业发展规划提供理论依据和科学指导。同时，拟把此套模型技术推广和应用到整个松嫩平原地区，保证农业安全生产，促进生态环境稳定健康发展。     

黑龙港地区农业—水资源—环境系统分析

通过现状农业—水资源—环境系统分析与诊断发现,黑龙港地区农业结构失调,背离资源条件发展农业,超采地下水,已使该区面临水资源不能永续利用、环境不断恶化的威胁;认为①立足水资源条件发展农业,是建立协调优化的农业—水资源—环境系统,实现农业可持续发展的必要前提;②采用综合措施有效利用土壤水,科学灌溉微咸水,合理开发利用地下水和地表水,是提高水资源对农业贡献的关键;③加强综合科技投入和农村市场经济建设,发展集约化农业,是在有限水资源条件下提高农业生产效率的重要保证;④提高全社会对可持续发展的认识,进行相应的能力建设,是实现黑龙港地区农业—水资源—环境协调可持续发展的社会基础。     

农田排水沟渠的环境效应与生态功能综述

农田排水沟渠作为农业景观中重要的景观单元,能够调节农田生态系统水分平衡,改变流域水文情势。农田养分可以随排水过程迅速流失,也可以通过沉淀与吸附机制被农田沟渠所截留或者通过植物吸收后收割与反硝化去除等机制脱离农田生态系统。作为农田生态系统边缘的交错带,农田排水沟渠较高的植物多样性可以提供动物栖息地和避难场所,增加农田生态系统生物多样性。清淤、收割和控制排水等管理措施对于农田排水沟渠的环境效应和生态服务功能有着不同的影响。今后应加强从多个学科研究农田排水沟渠的环境效应和生态功能,探索生态排水沟渠的构建和管理技术,实现农田排水沟渠水利功能和生态功能的"双赢"。     

黑河流域节水生态农业与流域水资源集成管理研究领域

概述了中国内陆河流域面临的水问题和日益激化的用水矛盾,强调了内陆河地区支柱产业——绿洲农业应该坚持节水和生态的方向,流域集成管理是持续农业的基础。长期从事该方面研究的黑河流域是个较好借鉴,同时也提供了深入开展相关研究的基础,为此提出了以黑河流域为背景的四大研究流域：水文、生物、经济系统水循环与水资源形成演变,节水农业的生物学研究与抗旱品种繁育,农业节水新材料研发与工程节水技术集成,水资源合理配置与流域集成管理;并简述了各领域的主要方向。     

基于地学规律的科尔沁沙地土地整治与生态修复规划方法

内蒙古科尔沁沙地历史上曾是科尔沁大草原,现在是农牧交错区,该区的土地利用关系到生态安全、国家粮食安全和农民生计。该区域“坨甸相间”地貌特点造成不同地形部位土壤含水量存在差异,降水量年际变化大。通过卫星影像数据解译出土地利用/覆被类型图与土壤图进行叠加,获得了显性沙地和隐性沙地数量与分布信息。首先保留耕地以外的其他地类,再利用卫星影像数据反映不同降水年型耕地的归一化植被指数(NDVI),将偏欠水年NDVI低于平均值的耕地退耕还草,消除这些耕地的冬春沙化风险,以进行土地利用布局调整。这种直接利用遥感数据获取土地利用/覆被类型和耕地的NDVI进行土地利用空间布局调整的方法,十分简单实用。本文还根据地貌和沙地降水入渗快的特点,提出了与高标准农田建设模式不同但与区域地理环境相吻合的农田整治模式,即利用自然沙丘作为区域风沙防护工程,土地开发不做大平整,不修建灌溉系统,发展雨养农业。以上根据区域地理环境条件进行土地利用布局和确定农田开发建设模式,可将农业生产与荒漠化防治和谐结合在一起,实现土地可持续利用。     

Farming the urban fringes of Barcelona: Competing visions of nature and the contestation of a partial sustainability fix

While the concept of urban agriculture investigates the way in which disused land within the consolidated city is returned to its citizens through a variety of farming practices, many pockets of rural land in peri-urban areas continue to be contested by institutions and communities – including informal farmers, formal farmers, municipal planners, metropolitan agencies, and investors – with contrasting interests. To date however, little scholarly attention has been paid to informal practices within the degraded areas of urban fringes and, more specifically, to the link between the expansion of peri-urban agriculture and the civic appropriation and negotiation of space in neglected peripheral areas. In this paper, we ask how a metropolitan sustainability fix is produced and contested both materially and discursively. We also explore how local residents involved in peri-urban agriculture claim the use of land for agricultural practices and in turn attempt to influence the urban agenda of the neoliberal city. Inquiring how competing visions of nature act as obstacles in this negotiation process, our analysis of the peri-urban Baix Llobregat Agricultural Park in Barcelona reveals that the imposition of official visions about how needs for food and agriculture should be fulfilled, which landscapes are esthetically acceptable, what nature is, and how land should be controlled and developed indicate why apparently “marginal” and informal urban agriculture in the periphery has come to be subordinated to the planning of the neoliberal city and of a metropolitan sustainability fix – a partial sustainability fix that is however progressively being questioned and renegotiated.     

北极沿岸地区水体中氢氧稳定同位素组成及水分转化过程研究

2010年7月参加第三届北京中学生北极科学考察活动,收集了北极沿岸地区的挪威斯瓦尔巴德群岛(Svalbard)、冰岛、格陵兰沿岸地区的海水、沿岸海水、海冰表面冰样、地表径流等水体样品,对样品进行了氢氧稳定同位素成分测定,分析了北极沿岸地区水体的水循环过程.结果表明,该地区不同水体中的稳定同位素具有不同特征.沿岸海水中δ...     

农业土地利用对岩溶地下水影响研究综述

地球表层系统最突出的景观标志是土地利用/土地覆被。人类通过土地利用改变天然土地覆被从而对脆弱敏感的岩溶水文系统产生了重大的影响。文章着重从农业土地利用出发综述了当前农业土地利用对岩溶水影响的研究。农业土地利用对岩溶地下水的影响主要围绕着水质和水量两个核心从以下几个方面展开:天然植被的清除,农业灌溉和排水,农业集约化所带来的化肥杀虫剂等的使用以及污染物质在岩溶含水层中的运移和影响。在此基础上作者从研究内容,理论方法和建立模型等方面都提出了自己的想法和建议。      

中国的用水何时达到顶峰

从中国实际用水增长业已放慢的趋势、已经开始启动的供水价格的大幅上升趋势和水价与用水的关系、经济增长方式由粗放型向集约型转变(高耗水行业已经接近顶峰)和用水与产业结构的关系、日益严格的环境立法和执法对用水的影响、中国水资源本身的限制等5个方面,分析中国的用水变化趋势,提出中国的农业用水量、工业用水量和总用水量目前均已接近顶峰,可望在10年内达到顶峰,最大用水量不大可能超过6500×108m3。     

Human-induced sedimentological changes in Manzala Lagoon, Nile Delta, Egypt

 The Manzala Lagoon in Egypt's Nile Delta has become a sediment sink of reduced area and depth, with increased contaminant levels. Loss of much-needed fresh to brackish water reserves and decreased fish catches have serious ramifications. Herein, maps of temporal and regional sediment distributions in Manzala incorporate petrological and statistical analyses of 200 surficial and short core samples. These provide baseline information needed to help implement protection measures for this vital wetland. Four periods are considered: 1920s, 1940s, ∼1965, and 1990. Important depositional changes between 1940s and ∼1965 resulted from anthropogenic effects on this quasi-closed lagoon system, including industrial buildup, wetland conversion to agricultural land, and irrigation waterway development. Further modification from ∼1965 to 1990 is associated with closure of the Aswan High Dam, continued construction of waterways that discharge waste water into lagoon margins, and marine incursion into the northern lagoon. If current practices continue, the lagoon could be reduced to about one-third of its present area by 2050 AD. Received: 2 October 1997 · Accepted: 13 January 1998     

The types,structure and results of the dike-pond system in South China

Conclusion The dike-pond system is an excellent artificial ecological agriculture system. With its special structure, it has many advantages compared with the other agricultural productions. In the system, the fertilizer, water and soil can be readjusted automatically, and flood and drought calamities can be prevented, so that the inferior land can be made fertile. The residues from planting and from stock/poultry raising can be recycled within the system. It is the most important that the fertilizer and feeds can be satisfied from within the system. This in itself could be a kind of break-through in agricultural development. A new form of fish feed supply is created saving input of purchased fertilizer and feeds as well as enhancing the development of planting, fishery and animal husbandry.The system has been attracting more and more attention from home and abroad. It has spread quickly to some other parts of China, and has begun to be appear abroad. The system is suitable for the areas with resembling the Pearl River delta elsewhere in Asia, Africa and South America, especially for lowlying water-logged land which is normally reclaimed by constructing water conservancy projects. In the latter case, the cost of pumping water is high, but the system is generally unstable compared with the stable, high yield dike-pond system. So a brilliant future can be envisaged for the dike-pond system.     

Simulation of nitrogen and phosphorus loads in the Dongjiang River basin in South China using SWAT

Population growth, urbanization, and intensified agriculture have resulted in mobilization of nitrogen and phosphorus, which is the main cause of river water quality deterioration. Environmental regulation has expedited the necessity for agricultural producers to design and implement more environmentally suitable practices. Therefore, there is a need to identify critical nutrients and their loss/transport potential. Watershed model can be used to better understand the relationship between land use activities/management and hydrologic processes/water quality changes that occur within a watershed. The objective of the study is to test the performance of the SWAT model and the feasibility of using this model as a simulator of water flow and nitrogen and phosphorus yields over the Dongjiang River basin in South China. Spatial data layers of land slope, soil type, and land use were combined with geographic information system (GIS) to aid in creating model inputs. The observed streamflow and sediment at Boluo station in the Dongjiang River basin were used to calibrate and validate the model. Time series plots and statistical measures were used to verify model predictions. Predicted values generally matched well with the observed values during calibration and validation (R ²≥0.6 and Nash-Suttcliffe Efficiency ≥0.5) except for underestimation of sediment peaks and overestimation of sediment valleys at Boluo. This study shows that SWAT is able to predict streamflow, sediment generation, and nutrients transport with satisfactory results.     

作物水生产力评估方法研究

农业用水作为消耗水资源最多的部分, 在全球和区域水资源消耗中占据很大比例. 农业水生产力的评价对于改进区域农业水资源利用方式, 促进农业经济发展具有重要意义, 尤其是在水资源匮乏地区. 首先阐述了作物水生产力的基本概念, 分析了影响作物水生产力的核心要素; 其次总结了作物水生产力的评价方法, 将其分为收获方法、 模型方法和集成遥感或GIS的模型方法, 并分析了这三类方法优缺点; 最后对作物水生产力研究发展趋势进行了展望, 认为将RS或GIS与模型结合用来估算作物水生产力的方法, 将是目前研究的发展方向.