Reconnecting crop and cattle farming to reduce nitrogen losses to river water of an intensive agricultural catchment (Seine basin,France): past,present and future

Nitrate and pesticide contamination of surface and groundwater has become a major problem in intensive farming regions in Europe, with nitrate concentrations reaching values above the standard defined in 2000 by the European Water Framework Directive. In the Seine basin, a major issue is the closure and abandonment of drinking-water wells, which force water managers and drinking-water producers to explore solutions for water resource protection. Organic farming has appeared as a credible alternative to conventional farming, and this study explores the potential of organic farming to reconcile agricultural production and water quality. On the basis of agricultural statistics, survey questionnaires and experimental data, the nitrogen soil surface balance (N-SSB) has been established at the scale of a small 104-km² catchment (The Orgeval sub-basin), representative of the intensive cash crop farming in the Seine basin. The N-surplus for arable land in specialized organic cash crop systems has been found to be half that of current conventional systems (15 kg N ha⁻¹ yr⁻¹ versus 30 kg N ha⁻¹ yr⁻¹, respectively). The N-yield in organic systems is 21% lower than in conventional systems, but total fertilization (mostly symbiotic N fixation) is also 26% lower. Whereas 2–3 years of forage legume (e.g., alfalfa) as a starter crop of the typical 7- to 10-year diversified rotation builds up N soil fertility and helps prevent weeds without pesticides, the existence of an outlet for this fodder production is a limiting factor for the economic sustainability and the environmental benefits of these farming systems. Therefore, we explored the possibility of a reconnection of livestock and crop farming systems in the Orgeval catchment, a traditional dairy farming and Brie cheese production region. We calculated the N-SSB for this type of a reconnected livestock and cropping system and found a value very close to the specialized organic cash crop system with full utilization of fodder production, leading to profitable animal production, essentially as milk in this farm design. This reconnected system is compared with the estimated situation in 1955 before separation of plant and livestock production. Furthermore, the N-SSB values were converted into infiltrating sub-root concentrations and used as a boundary condition to a biogeochemical model. Organic cropping and organic reconnected livestock cropping systems result in a 50% reduction of surface water nitrate concentrations, a surface water quality 20% better than that reconstructed for 1955, with an overall higher protein production.     

四川省畜牧养殖业污染现状及防治研究

畜禽养殖业污染问题近年已成为农村污染的主要来源.通过对四川省畜禽养殖业主要污染物排放现状进行阐述,分析四川省畜禽规模化养殖和养殖专业户生产情况,以及对5种畜禽主要污染物产排污系数的分析,提出四川省畜禽养殖污染防治的技术指导.     

Variations in land requirements for meat production

Production of meat requires substantial amounts of feed grains which in turn require vast amounts of land. Future population growth and increase in consumption will raise the demand for meat and with it the land required for meat production. This paper analyses the various factors that affect land requirements for meat production. Meat production by Dutch broilers, pigs and beef cattle on their current feeds are compared and options for change are evaluated with respect to their nutritional needs. Differences in land requirements of a factor of 3 were found between different agricultural production systems and feeds as well as between types of livestock. It is shown that broilers have the lowest land requirement while beef cattle have the highest. The variation in feed crop yields between agricultural systems is discussed. It is concluded that due to the large variation within the system there is potential for reduction in the land requirements for meat production.     

畜禽养殖场污染状况监测与评价

对河南省三个有代表性的规模化养殖场污染物排放及其对周围环境的影响进行了调查、监测及评价,结果表明,畜禽养殖污染已成为农业面源污染的重要来源,对其周围地表水和地下水产生较大影响。     

Living Amidst Large Wildlife: Livestock and Crop Depredation by Large Mammals in the Interior Villages of Bhadra Tiger Reserve,South India

Conflict with humans over livestock and crops seriously undermines the conservation prospects of India's large and potentially dangerous mammals such as the tiger (Panthera tigris) and elephant (Elephas maximus). This study, carried out in Bhadra Tiger Reserve in south India, estimates the extent of material and monetary loss incurred by resident villagers between 1996 and 1999 in conflicts with large felines and elephants, describes the spatiotemporal patterns of animal damage, and evaluates the success of compensation schemes that have formed the mainstay of loss-alleviation measures. Annually each household lost an estimated 12% (0.9 head) of their total holding to large felines, and approximately 11% of their annual grain production (0.82 tonnes per family) to elephants. Compensations awarded offset only 5% of the livestock loss and 14% of crop losses and were accompanied by protracted delays in the processing of claims. Although the compensation scheme has largely failed to achieve its objective of alleviating loss, its implementation requires urgent improvement if reprisal against large wild mammals is to be minimized. Furthermore, innovative schemes of livestock and crop insurance need to be tested as alternatives to compensations.     

Livestock grazing and habitat for a threatened species: Land-use decisions under scientific uncertainty in the White Mountains,California, USA

The North Fork of Cottonwood Creek, in the White Mountains, Inyo National Forest, California, is a critically important refuge for the Paiute cutthroat trout (Oncorhynchus clarki seleniris), a federally listed threatened species. Habitat for these fish appears to be limited by excessive levels of fine sediment in the channel, and livestock grazing of riparian meadows has been implicated in delivery of sediment to the channel. However, the relationships between land use and sediment yield have not been conclusively determined, in large part because there are no historically ungrazed sites to serve as long-term controls. Accordingly, land-use decisions must be made under scientific uncertainty. To reduce erosion and sedimentation in the stream, the Forest Service spent approximately US$260,000 from 1981 to 1991 to repair watershed damage from livestock grazing, prevent livestock from traversing steep banks, and limit livestock access to the channel. Throughout this period, livestock grazing has continued on these lands, yielding less than $12,000 in grazing fees. In revising its Allotment Management Plan for the basin, the Forest Service rejected the “no-grazing” alternative because it was inconsistent with its Land and Resource Management Plan, which specifies there is to be no net reduction of grazing. Joint appointment with the University of California White Mountain Research Station, East Line Street, Bishop, California 93518, USA.     

畜禽养殖废水的硝化性能研究

针对近年来我国规模化养殖场迅速发展所带来的严重环境污染,特别是畜禽养殖废水中氨氮污染物所产生的污染,文章采用硝化反应器对其进行处理。首先进行了硝化细菌的培养驯化,然后通过连续运行试验和间歇运行试验,考察氨氮的去除效果和操作参数的影响。试验结果表明:当温度为25℃,pH为6.0~8.0,DO为4.0~6.0 mg/L,HRT为12 h,进水氨氮为200 mg/L时,出水氨氮浓度可以降低到1.0 mg/L左右,氨氮的去除率达到接近100%。     

The role of economic invisibility in development: veiling women's work in rural Pakistan

The thesis in this article is that both women's work and its invisibility are essential to development, and at two levels: to the economy of rural households and to the wider development process. For rural households, the case of Pakistan suggests that the veils that conceal women's work shield a portion of household production from the risks and extractions inherent in their involvement with development. This shielded production depends on off-farm natural resources of which the use is also veiled. For States and other development interests, the author suggests that women's work constitutes a subsidy which is intentionally invisible. The subsidy of women's labour is linked to a forest-to-farm subsidy. Women's invisible work, in other words, is not invisible because it is not seen, but because the process of economic development—for both rural households and States and other development actors—requires that it be hidden.     

畜禽养殖废水的三维荧光特征

对某畜禽养殖废水连续采样,利用荧光光谱法研究畜禽养殖废水的三维荧光特性.结果表明:该废水的三维荧光光谱有两个荧光峰,分别为270 nm/297 nm和315 nm/410 nm,两峰的强度之比为3.45～4.94;该畜禽养殖废水由蛋白质、腐酸、尿液及阴离子表面活性剂组成;各峰的峰位置及峰强度比值都可作为判断废水是否为该...     

基于监测数据的规模化畜禽养殖面源污染总量测算研究

随着我国规模化畜禽养殖业的发展,畜禽养殖面源污染已超过工业源和生活源污染,成为最大的污染源,也成为"十二五"污染减排的重点。本文从规模化畜禽养殖面源污染影响因素分析着手,提出基于监测数据的"产生-削减-面源体现系数法"的畜禽养殖面源污染总量测算方法,并给出了计算公式和总量测算流程,最后以内江市规模化畜禽养猪场为例,介绍了总量测算过程,给出了内江市规模化养猪场面源污染总量。