Trends in food production and nitrous oxide emissions from the agriculture sector in India: environmental implications

We studied trends in food production and nitrous oxide emissions from India's agricultural sector between 1961 and 2000. Data from Food and Agricultural Statistics (FAO) have been gathered covering production, consumption, fertilizer use and livestock details. IPCC 1996 revised guidelines were followed in studying the variations in N₂O-N emissions. Results suggest that total N₂O-N emissions (direct, animal waste and indirect sources) increased ~6.1 times from ~0.048 to ~0.294 Tg N₂O-N, over 40 years. Source-wise breakdown of emissions from 1961–2000 indicated that during 1961 most of the N₂O-N inputs were from crop residues (61%) and biological nitrogen fixation (25%), while during 2000 the main sources were synthetic fertilizer (~48%) and crop residues (19%). Direct emissions increased from ~0.031 to ~0.183 Tg. It is estimated that ~3.1% of global N₂O-N emissions comes from India. Trends in food production, primarily cereals (rice, wheat and coarse grains) and pulses, and fertilizer consumption from 1961–2000 suggest that food production (cereals and pulses) increased only 3.7 times, while nitrogenous fertilizer consumption increased ~43 times over this period, leading to extensive release of nitrogen to the atmosphere. From this study, we infer that the challenge for Indian agriculture lies not only in increasing production but also in achieving production stability while minimizing the impact to the environment, through various management and mitigation options.     

Soil conservation policy in the United States

Soil conservation has been a matter of federal natural resource policy for over a half century in the United States. A variety of federal programs have been undertaken to encourage soil conservation. There are goals which are essential to these programs, and there are related ancillary programs with different goals which often have had an impact on the extent to which the central soil conservation objectives have been effectively implemented. This article analyzes four aspects of federal soil conservation goals and programs: the evolution of the constellation of soil conservation goals, the problems with goal implementation, implementation effectiveness, and the appropriateness of the implementation and administration of federal goals.     

Agricultural and non-agricultural settlements for drought-afflicted pastoralists in Somalia

The severe drought of 1973–1975 in Somalia had major impacts on pastoral populations, many of whom moved into specially established camps where food, water and medical assistance were provided by the government and international agencies. At the end of the drought it was decided to settle the remaining 120,000 people in six settlements, three of which were agricultural and three oriented towards fishing. This paper analyzes these settlements, with particular attention paid to agricultural systems, organization and socioeconomic characteristics. Some of the problems facing the settlements included their location, administrative structure and relative overemphasis on social services as opposed to development of production and income generating activities. It is shown that the socioeconomic viability of settlements would be enhanced if careful studies were undertaken beforehand and if a diversified development strategy were employed.     

AGRICULTURAL CONSERVATION PROGRAM: AN EVALUATION1

The Agricultural Conservation Program (ACP), is undergoing a new, rigorous evaluation to determine its effectiveness in conserving the Nation's agricultural soils and waters. ACP deals with many types of conservation practices, but the focus here is on the evaluation of soil and water related practices. ACP has depended heavily on the State and private forestry services, Soil Conservation Service, and the Cooperative Extension Services, for technical expertise. Thus, the process is an evaluation of the effectiveness of a “team of agencies,” as well as of the program itself. Results of the evaluation have helped to develop new thrusts which have moved ACP further into the position of treating the total conservation problem. Phase I has its limitations. It did not address the impact of wind erosion, water quality, change in productive capacity, soil quality, wildlife habitat, off site and farm income impacts. It does show that ACP has and is doing a very good job in meeting its stated purposes. It is clear that ACP's effectiveness can be improved with more and better advanced planning and more intensive use of soil maps, the USLE, and other scientific tools. ACP is headed in this direction.     

农业气象灾害分析网络服务系统

以大量翔实的农业气象灾害资料为基础,结合实时农业气象灾情分析,在ｗｉｎｄｏｗｓＮＴＳｅｒｖｅｒ网络环境下,研制出具有网络功能的农业气象灾害分析服务系统,系统在Ｉｎｔｅｒｎｅｔ的ＮｅｔｓｃａｐｅＮａｖｉｇａｔｏｒ或Ｅｘｐｌｏｒｅｒｔｏ览器下运行,简便实用．系统以灾害服务为宗旨,体现了信息量大、服务迅速的特点。内容包括农业气象灾害类型库、逐年农业气象灾害评判库、实时农业气象灾害分析及灾情服务流程．     

Adsorption–desorption behavior of atrazine on agricultural soils in China

Adsorptionanddesorptionareimportantprocessesthataffectatrazinetransport,transformation,andbioavailabilityinsoils.Inthisstudy,theadsorption–desorptioncharacteristicsofatrazinein three soils (laterite, paddy soil and alluvial soil) were evaluated using the batch equilibrium method. The results showed that the kinetics of atrazine in soils was completed in two steps: a “fast” adsorption and a “slow” adsorption and could be well described by pseudo-second-order model.In addition,the adsorption equilibrium isotherms were nonlinear and were well fitted by Freundlich and Langmuir models. It was found that the adsorption data on laterite, and paddy soil were better fitted by the Freundlich model;as for alluvial soil,the Langmuir model described it better. The maximum atrazine sorption capacities ranked as follows: paddy soil > alluvial soil > laterite. Results of thermodynamic calculations indicated that atrazine adsorption on three tested soils was spontaneous and endothermic. The desorption data showed that negative hysteresis occurred. Furthermore, lower solution pH value was conducive to the adsorptionofatrazineinsoils.Theatrazineadsorptioninthesethreetestedsoilswascontrolled by physical adsorption, including partition and surface adsorption. At lower equilibrium concentration, the atrazine adsorption process in soils was dominated by surface adsorption;while with the increase of equilibrium concentration, partition was predominant.     

Local PM10 and PM2.5 emission inventories from agricultural tillage and harvest in northeastern China

Mineral particles or particulate matters(PMs) emitted during agricultural activities are major recurring sources of atmospheric aerosol loading.However,precise PM inventory from agricultural tillage and harvest in agricultural regions is challenged by infrequent local emission factor(EF) measurements.To understand PM emissions from these practices in northeastern China,we measured EFs of PM_(10) and PM_(2.5) from three field operations(i.e.,tilling,planting and harvesting) in major crop production(i.e.,corn and soybean),using portable real-time PM analyzers and weather station data.County-level PM_(10) and PM_(2.5) emissions from agricultural tillage and harvest were estimated,based on local EFs,crop areas and crop calendars.The EFs averaged(107 ± 27),(17 ± 5) and 26 mg/m~2 for field tilling,planting and harvesting under relatively dry conditions(i.e.,soil moisture 15%),respectively.The EFs of PM from field tillage and planting operations were negatively affected by topsoil moisture.The magnitude of PM_(10) and PM_(2.5) emissions from these three activities were estimated to be 35.1 and 9.8 kilotons/yr in northeastern China,respectively,of which Heilongjiang Province accounted for approximately45%.Spatiotemporal distribution showed that most PM_(10) emission occurred in April,May and October and were concentrated in the central regions of the northeastern plain,which is dominated by dryland crops.Further work is needed to estimate the contribution of agricultural dust emissions to regional air quality in northeastern China.     

A dual-interval fixed-mix stochastic programming method for water resources management under uncertainty

In this study, a dual-interval fixed-mix stochastic programming (DFSP) method is developed for planning water resources management systems under uncertainty. DFSP incorporates interval-parameter programming (IPP) and fuzzy vertex analysis (FVA) within a fixed-mix stochastic programming (FSP) framework to address uncertain parameters described as probability distributions and dual intervals. It can also be used for analyzing various policy scenarios that are associated with different levels of economic consequences since penalties are exercised with recourse actions against any infeasibility. A real case for water resources management planning of Zhangweinan River Basin in China is then conducted for demonstrating the applicability of the developed DFSP method. Solutions in association with α-cut levels are generated by solving a set of deterministic submodels, which are useful for generating a range of decision alternatives under compound uncertainties. The results can help to identify desired water-allocation schemes for local sustainable development that the prerequisite water demand can be guaranteed when the available water resource is scarce.