Expansion of agricultural oasis in the Heihe River Basin of China: Patterns,reasons and policy implications

The Heihe River Basin (HRB) is the second largest inland river basin in the arid region of northwestern China. An agricultural oasis is a typical landscape in arid regions providing precious fertile soil, living space and ecological services. The agricultural oasis change has been one of the key issues in sustainable development in recent decades. In this paper, we examined the changes in the agricultural oasis in HRB and analyzed the socio-economic and climatic driving forces behind them. It was found that the agricultural oasis in HRB expanded by 25.11% and 14.82% during the periods of 1986–2000 and 2000–2011, respectively. Most of the newly added agricultural oases in HRB were converted from grassland (40.94%) and unused land (40.22%). The expansion in the agricultural oasis mainly occurred in the middle reaches of HRB, particularly in the counties of Shandan, Minle, Jinta and Jiuquan city. Changes in the rural labor force, annual temperature and precipitation have significant positive effects on agricultural oasis changes, while the ratio of irrigated agricultural oases has significant negative effects on agricultural oasis changes. The agricultural oasis expansion in HRB is the combined effect of human activity and climate change.     

The common agricultural policy and the general environmental policies concerned with agriculture in the European Community and their implications for fertilizer consumption

This paper traces the major developments in the European Common Agricultural Policy (CAP) and related environmental policy and examines their impact on the use of crop nutrients. The objectives of the CAP were set out in the Treaty of Rome in 1957 and have not been explicitly revised. The Community has, however, progressed from being a significant importer to a major exporter of food. Various changes in the policy measures/reforms, have been implemented, each to control the continuing increase in farm output. The latest of these in May 1992 reduced commodity prices towards world market levels, introduced 15% set aise for arable land, as well as agreeing a number of agri-environmental measures. Further changes are anticipated following the Uruguay Round of the General Agreement on Tariffs and Trade (GATT) and as new trade agreements are reached with the countries of the former Eastern Bloc. Inevitably, existing farm systems will be subject to careful reappraisal. The Community's environmental objectives were added to the Treaty in 1987 with the passing of the European Single Act. The interaction between agriculture and the environment has been a prominent concern. The Directive 91/676, which seeks to protect water against pollution caused by nitrate from agricultural sources, is the first Directive to have a major direct impact on farm practive. The Fifth Environmental Action Plan for 1993–2000 ‘Towards Sustainability’ selects agriculture as one of five industries for specific attention. The plan seeks an extensification of agriculture and a reduction in the use of chemicals. Changes in the amount of plant nutrients from both farmyard manure and mineral fertilizers used in agriculture are quantified. Methods of determining the efficiency with which they are utilized are assessed. New advisory techniques which will improve the efficiency of nutrient use on the farm are considered, as are the implications for the future demand for nutrients from mineral fertilizers. This paper is the view of the European Fertilizer Manufacturers Association.     

Bio-Organic Geochemistry research in China: Advances,opportunities and challenges

The discipline of “Bio-Organic Geochemistry” is a cross research field between biogeochemistry and traditional organic geochemistry, which focuses on geochemical processes related to the biosynthesis of organic molecules (particularly lipids) by (micro) organisms, organic matter production by primary producers, degradation of organic matter by microbial processes recorded by retainable lipid biomarkers, and organic proxies for studies of paleo-climate, paleo-environments, paleoecology and Earth evolution. This field aims to go beyond the traditional petroleum-oriented Organic Geochemistry by integrating with biogeochemical concepts concerned mostly with biomolecules from cellular material such as DNA and lipids. A formal Chinese organization in Bio-Organic Geochemistry was established in 2012 when the first conference was held in Guangzhou. This organization has witnessed rapid growth over the past six years with focused research addressing organic proxies in paleoclimate and paleoenvironmental applications, with particular rapid development in glycerol dialkyl glycerol tetraethers-derived proxies. Most progresses in China so far are made following or paralleling the international trend in biogeochemical studies. Things have begun to change with China’s ambitious initiatives in several bio-geo programs such as the Ocean Deep Drilling Program of China, the Microbial Hydrosphere Program, the Deep Carbon Observatory, and the Microbiome Program. Looking forward in the 21st Century, the growing Chinese research community in Bio-Organic Geochemistry faces grand opportunities and challenges as Chinese scientists propel themselves toward global research frontiers.     

Data use and information creation: challenges for marine scientists and for managers

In the coastal waters of European countries and in the offshore waters of the north-east Atlantic, there is an increasing need for scientists to meet challenging objectives, such as to identify meaningful measures of 'quality', and to recommend 'indicators' to underpin implementation of directives, conventions, statutes and other more informal national and international initiatives. Those indicators may relate to particular species or habitats, to changes in physical and chemical characteristics, and even to the use to which the system is put. The problems to be overcome are difficult, but new and developing approaches will make a significant contribution. The approaches include: criteria to identify 'sensitivity' and 'importance', structures to organise information and electronic information resources to access data.The real challenge is to make the results of the various scientific initiatives relevant to and understandable by a wide range of customers with similar overlapping requirements, and thus make a genuine contribution to protecting the marine environment. Above and beyond that is the need for scientists to drive the agenda to enable real and lasting progress to be made towards ecosystem-based management of our seas and a proper consideration of what 'sustainability' may mean in the marine environment and how we utilise its resources.     

Prehistoric agriculture development in the Yunnan-Guizhou Plateau,southwest China: Archaeobotanical evidence

The origin, development and expansion of prehistoric agriculture in East Asia have been widely investigated over the past two decades using archaeobotanical analysis from excavated Neolithic and Bronze Age sites. Research on prehistoric agriculture has predominantly focused in the valleys of the Yellow River and the Yangtze River. Agricultural development during the Neolithic and Bronze Age periods in the Yunnan-Guizhou Plateau of southwest China, an important passageway for human migration into Southeast Asia, still remains unclear. In this paper, based on macrofossil and microfossil analysis and radiocarbon dating at the Shilinggang site, we investigate plant subsistence strategies in the Nujiang River valley during the Bronze Age period. Combined with previous archaeobotanical studies in the Yunnan-Guizhou Plateau, we explore agricultural development processes in this area during the Neolithic and Bronze Age. Our results indicate that rice and foxtail millet were cultivated in Shilinggang around 2500 cal a BP. Three phases of prehistoric agricultural development in the Yunnan-Guizhou Plateau can be identified: rice cultivation from 4800–3900 cal a BP, mixed rice and millet crop(foxtail millet and broomcorn millet) cultivation from 3900–3400 cal a BP, and mixed rice, millet crop and wheat cultivation from 3400–2300 cal a BP. The development of agriculture in the Yunnan-Guizhou Plateau during the Neolithic and Bronze Age periods was primarily promoted by prehistoric agriculture expansion across Eurasia, agricultural expansion which was also affected by the topographic and hydrological characteristics of the area.     

尼罗河三角洲早—中全新世气候—环境变化对早期农业发展的影响

对尼罗河三角洲平原东北部一个古埃及文化遗址(Kom El-Khilgan)1.5 m长的沉积物剖面KH1开展14C测年、沉积物粒度和孢粉分析.根据岩性、粒度和测年等结果综合判定:剖面150~100 cm地层为早全新世河流相沉积;100~27 cm地层为早、中全新世(8000—4000 cal a BP)三角洲冲积平原沉积,其中涵盖了古埃及前王朝至古王国时期(6500—4131cal a BP)的人类活动信息;27~0 cm为现代表土层.孢粉分析结果反映了在距今8000~4000 a期间:1)研究区气候由湿润过渡为温和,最后趋于干旱;2)随着气候变干,尼罗河上游水文变化对三角洲环境影响减小,研究区由沼泽湿地逐渐过渡为干草甸环境,更多的土地可以被人类利用;3)常被用来指示农业活动的35μm禾本科、陶器碎片和炭屑的出现并逐渐增加,表明该遗址附近的人类农业活动始于距今6500 a左右,并持续至距今4000 a前后.上述证据表明尼罗河三角洲全新世早—中期湿润向干旱过渡的气候驱动了人类农业活动的开展.本研究为进一步探讨尼罗河三角洲古文明对环境适应性研究提供了科学依据.     

Supplemental Colorado River water for a developed groundwater agriculture: A problem of quantities,qualities and conjunctive use

Upon completion of the Central Arizona Project (CAP), Colorado River water will be delivered some 200 miles inland for agricultural, domestic, and industrial use. Any new importation of water to an area implies adjustments in the organization of the economy of the area. For irrigated agriculture, adjustments will occur in input mix, output mix, acreage farmed, and in gross and net incomes. A complicating factor associated with importation of Colorado River water is that the imported water will contain different dissolved salt concentrations than the groundwater and surface water currently being used.Mathematical programming models of representative irrigated farms in Pinal County, Arizona, are used to project adjustments implied under several assumptions as to the availability, cost and salinity of the various sources of irrigation water. Conclusions are drawn as to the potential winners and losers from project development. Conclusions include the following: Increased salinity should not be of concern to the farmers in the county and Indian farms will reap the greatest share of benefits from the Project.     

Water resources management in Lebanon: institutional capacity and policy options

Worldwide water resources are not uniformly distributed and generally scarce in arid and semi-arid zones such as the Middle East. Lebanon, which is located along the Mediterranean shores of the Middle East, remains blessed with relatively more water in comparison to its neighboring countries. Increased pressure on its water resources requires the formulation and implementation of a comprehensive management plan and strategic policies to pre-empt potential future water shortages. This paper examines existing water laws and regulations under the current institutional framework in Lebanon. Developmental policies and management strategies to address the potential water supply demand imbalance and meet future challenges are presented in the light of existing legal and regulatory constraints and institutional capacities.     

Water quality assessment for sustainable agriculture in the Wet Tropics--a community-assisted approach

A number of studies in north Queensland over the past two decades have concluded that large amounts of nutrients and sediments are exported from agricultural watersheds, particularly during wet season rainfall events. With the co-operation of a number of growers, runoff from Queensland Wet Tropics banana and cane farm paddocks in two distinct tropical river catchments was examined to provide an estimate of nutrient and sediment concentrations and export, with comparison to water quality of flow through a small urban lakes system. Median total nitrogen concentrations in cane drainage runoff (3110 microg N/L) were higher than for banana paddock drainage (2580 microg N/L), although the maximum concentration was recorded from a banana paddock (20,900 microg N/L). Nitrogen losses during post-event drainage flow were supplemented by high proportions of NO(X) (nitrate + nitrite) sourced from groundwater inputs. Banana paddocks had the highest maximum and median total phosphorus and TSS concentrations (5120 and 286 microg P/L, and 7250 and 75 mg/L respectively) compared to the cane farms (1430 and 50 microg P/L, and 1840 and 14 mg/L respectively). The higher phosphorus and TSS concentrations in the banana runoff were attributed to higher paddock slopes and a greater proportion of exposed ground surface during the wet season. Highest nutrient and TSS concentrations corresponded with samples collected near the peak discharge periods; however, the rising stage of the drainage flows, where the highest nutrient and TSS concentrations are often reported, were difficult to target because of the manual sampling strategy used. This study shows that high concentrations of nutrients and TSS occur in the runoff from cane and banana paddocks. Median total nitrogen, total phosphorus and TSS concentrations in flow through the urban lakes were 369 microg N/L, 16 microg P/L and 11 mg/L, respectively. Flux estimates of 9.2 kg N, 0.8 kg P and 126 kg TSS/ha were determined for drainage runoff from a banana paddock during a single intensive storm event.     

Water safety: management,perception and health implications in Santa agricultural area,North-West Region,Cameroon

ABSTRACT

Santa agricultural area is a key production site for crops in Cameroon. This study aimed to look at the risk factors, knowledge and health implications of water pollution across 10 villages, in the area: 140 water points were visited and questionnaires randomly administered to water users, while health data were collected from the two local hospitals. Water sources are tap, stream, rain, well and spring and the water is used for agriculture, domestic activities, hygiene and sanitation. Pesticide pollution was illustrated by activities such as spraying, mixing and management of waste containers and purification methods are chlorination, boiling, sedimentation, filtration and refrigeration. Waterborne diseases are cholera, typhoid (the most prevalent), diarrhea, dysentery and skin diseases. Many water sources are close to toilets, farms and dumping sites. We found that 75% of respondents were not satisfied with the quality of water. Our results will be interest for water management, and to educate users on the risks linked to current practices.     

Water resources,their use,and water availability in Russia: Current estimates and forecasts

The results of recent studies carried out in the State Hydrological Institute were generalized to present new data on the estimation of long-term dynamics of water resources and water use for all administrative regions of RF, as well as current and anticipated variations in water resources in the nearest future. Estimates were constructed for changes in water use, load on water resources, and water availability, especially in the recent two decades, during which Russia experienced most significant changes in the major factors determining the state of water resources, i.e., climate change and socio-economic transformations. Estimates are given for constituent entities of RF and for hydroclimatic regions of the country as a whole.     

Water content of ignimbrites: Lunar implications

The most important lunar resource may be ignimbrite because of its water content. The variation of water in tuff as a function of degree of welding, oxidation and flow thickness is of direct significance to lunar basing in volcanic terrains on the moon. The fact that many calderas on earth have ignimbritic « aprons » extending from them is correlatable with the apron-type ray patterns around certain post-mare and highland craters on the moon. If lunar craters can be positively identified with associated ignimbritic flows then such areas are potentially water richer than impacted environments. Electrolytic hygrometry and static dehydration analysis of the Tumulo Creek, Wineglass, Bishop, Pelée and Gharvegh tuffs indicate a wide span in water content from 0.2 to 4.1 % even within one flow unit. Devitrification of the mesostasis of these tuffs expels water. Water content apparently varies as a function of flow geometry and possibly thickness. The lower portions of the Tumulo Creek tuff are more hydrous than the upper portions. A slight increase in water content is observed with increase in oxidation. Most of the water in all welded tuffs analysed with the hygrometer is driven off at around 300°C suggesting polymeric hydroxyl bonding with dissociation energies ranging from 2 to 8 kilocalories per mole. However, other types of bonding — Van der Waal, coordinated hydroxyl, free monomeric hydroxyl, etc. — are probably also present. No single, simple bond type controls water retention in rocks. Lunar exploration techniques for hydrous portions of ignimbrite flows include the lateral and vertical application of the epithermal log.     

Water, heat fluxes and water use efficiency measurement and modeling above a farmland in the North China Plain

Net radiation (Rn), water vapor flux (LE), sensible heat flux (Hs) and soil heat flux (G)were measured above a summer maize field with the eddy-covariance technique, simulation and analysis of water, heat fluxes and crop water use efficiency were made with the RZ-SHAW model at the same time in this study. The results revealed significant diurnal and seasonal variability of water vapor flux for summer maize. Most part of Rn was consumed by the evapotranspiration of the summer maize. The proportion of water vapor flux to net radiation ((LE/Rn) increased with the crop development and peaked around milk-filling stage with a value of 60%, a slightly lower than that obtained by the RZ-SHAW model. Daily evapotranspiration estimated by the model agreed with the results measured with the eddy-covariance technique, indices of agreement (IA) for hourly water vapor fluxes simulated and measured were above 0.75, root mean square errors (RMSE) were no more than 1.0. Diurnal patterns of Hs showed the shape of inverted "U" shifted to the forenoon with a maximum value around 11:30 (Beijing time), while LE exhibited an inverted "V" with a maximum value at around 13:00, about an hour later than Hs. Diurnal change of CO2showed an asymmetrical "V" curve and its maximal rates occurred at about 11:30. Variations of water use efficiency during the phonological stages of the summer maize showed a rapid increase with the photosynthetic photon flux density (PPFD) after sunrise, a state of equilibrium around 10:00 followed a decrease. Maximum values of water use efficiency were 24.3, and its average value ranged from 7.6 to 10.3 g kg-1.     

Strongly peraluminous granites of Mesozoic in Eastern Nanling Range,southern China: Petrogenesis and implications for tectonics

The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±AI-rich biotite±tourmaline±garnet, and lack of cordierite. In respect of petrography, geochemistry, Nd isotope, and single grain zircon U-Pb dating, the representative granite bodies of them are studied. The research shows that these granites were emplaced in two stages, namely 228-225 Ma BP and J2-3 159-156 Ma BP, belonging to Indosinian and early Yanshanian periods, respectively, and they have low εNd(t) values (-10.6--11.1), high A/CNK, Rb/Sr ratios and tDM values (1887-1817 Ma), and REE's tetrad effect (TE1,3=1.13-1.34). In comparison with related geology, petrology and chronology of granites in adjacent regions, it is suggested that Indosinian SPGs of ENR formed in the circumstance of post-collisional extension 20 Ma after the major collision of Indosinian Movement (258-243 Ma BP) in Indo-China Peninsula, and early Yanshanian SPGs formed in the     

Polar climate system modeling in China: Recent progress and future challenges

The first fully coupled atmosphere-ocean-sea ice model developed in China was released in the mid-1990s. Since then, significant advances in climate system model developments have been achieved by improving the representations of major physical processes, increasing resolutions, and including an ice-shelf component. There have also been many modeling studies in China on the polar climate system, including weather and sea-ice numerical forecasts to meet the national needs of polar scientific expeditions, assessments of the state-of-the-art coupled model performance, and process-oriented studies. Future model developments and modeling activities will need to address several big scientific questions originating from the polar climate system: i) How will polar ice mass balance evolve and affect global sea level? ii) How can we properly simulate openocean deep convection and quantify its role in driving the lower branch of the global overturning circulation? iii) How are Arctic and Antarctic connected and what caused the contrasting sea ice trends in the two polar regions over the last decades? To address these questions, polar climate system modelers will need to analyze extended observational datasets on a global scale and work together with other polar researchers to develop a more comprehensive and sustainable observation system in the polar regions.     

Chrome-rich clinopyroxene in orthopyroxenite from Maowu, Dabie Mountains, central China: A second record and its implications for petrogenesis

A second occurrence of chrome-rich clinopyroxene has been discovered as inclusions in orthopyroxene in orthopyroxenite from Maowu, the Dabie Mountains, Central China. The average formula for chrome-rich clinopyroxene can be expressed as (Na_0.39Ca_0.54)_0.93(Mg_0.57Fe²⁺_0.06Fe³⁺_0.01Cr_0.24Al_0.15)_1.03Si_2.02O₆, with a maximum amount of kosmochlor component of 28.52 mol%. The unit cell parameters obtained from a single-crystal are a  = 9.614 Å, b  = 8.800 Å, c =  5.240 Å, β = 106.59°, space group C2 / c . The indices of refraction are α = 1.697, β = 1.704, γ = 1.726. Chrome-rich clinopyroxene, which coexists with chromite, chromian rutile and chromian pyrope, crystallized at a temperature of 1025 °C and very high pressure, and therefore represents a mantle relic. Together with the appearance of low-pressure inclusion mineral assemblage and the estimation of physical–chemical conditions for matrix minerals, the Maowu eclogite–ultramafic complex is considered to be formed during ultrahigh-pressure metamorphism from the mantle-derived protolith.     

Environmental challenges in Polish agriculture covering a main area of the Baltic Sea Basin

Poland largely encompases the estuary of the Vistula and Odra rivers, which drain into the Baltic Sea. Only a very small area of the south-east part of the country is within the Black Sea Basin. Poland contributes significantly to the pollution of the Baltic Sea, with biogenic nutrients and organic substances. Poland includes more than half the coastal inhabitants of the Baltic Sea, and they use 40% of the arable land situated there. The contribution to the pollution of this sea with nitrogen, phosphorus and organic substances is approximately 30, 40 and 22%, respectively. The main sources of nutrients are untreated sewage and the runoff and leakage of fertilizers from agricultural land. The natural conditions in Poland are poorer than in Western Europe due to the prevalence of light soils and a short growing period with frequent droughts. After correcting the synthetic index for soil and climate, it was estimated that for each inhabitant of Poland there are 0.3 ha of farmland, which is comparable to that of Western Europe. For the maintenance of the population, intensive agricultural production must be accompanied by environmental protection regulations. Polish agriculture is not only a polluter but also a recipient of pollution, especially the deposits of sulphur and heavy metals emitted by industry and municipal areas. The estimated annual emission of sulphur dioxide is about 4 million t, which equals an average deposit of about 90 kg of sulphur per hectare of farmland. The pedological processes and acid deposits cause more than 60% of agricultural land in Poland to be acidic. The contamination of soils with heavy metals in general is lower than in Western Europe, but in some areas (e.g. Upper Silesia) it exceeds the safe limits.