The multiple cropping is the main agricultural production pattern, including double cropping of rice in south China and double cropping of wheat and corn in north China. Household investigation, typical farmland survey and county statistics inspection were performed to analyze the status and countermeasure of nitrate pollution in China. The result showed that the nitrate rate of underground wat...

The objective of this paper is to report the cumulative effects of cropping system intensification on the near surface soil physical properties (surface one inch of soil) within the Colorado dryland agroecoystem project, which has been in existence since 1986. Intensifying cropping systems from wheat-fallow to wheat-com-fallow to continuous cropping, increased crop residue return to the soil. R...

This study was conducted to explore the changes in soil microbial populations, enzyme activity, and tuber yield under the rotation sequences of Potato-Common vetch (P-C), Potato-Black medic (P-B) and Potato-Longdong alfalfa (P-L) in a semi-arid area of China. The study also determined the effects of continuous potato cropping (without legumes) on the above mentioned soil properties and yield. T...

The Brazilian agro-industrial frontier in Mato Grosso rapidly expanded in total area of mechanized production and in total value of production in the last decade. This article shows the spatial pattern of that expansion from 2000 to 2010, based on novel analyses of satellite imagery. It then explores quantitatively and qualitatively the antecedents and correlates of intensification, the expansi...

The common phenomenon of sublethal predation in soft-bottom bivalves usually involves nipping of siphons. Here we show that foot cropping, hitherto documented only in Donax spp., is widespread in the New Zealand cockle Austrovenus stutchburyi (Veneridae). Depending on the locality, cropping frequency ranged between 14 and 34% of cockles, and the average proportion of the foot area cropped range...

Alfalfa is a perennial herbaceous forage legume that remarkably and negatively affected by monocropping. However, the contribution of changes in bacterial communities to soil sickness alfalfa have not been elucidated. Therefore, we investigated community structures response monocropped along chronosequence. Continuous cropping reduced alpha diversity altered structures, pH, total P available we...

the slow pool, with decadal turnover times, while 5% of the SOC is found in the rapidly cycling active fraction, Previous studies of no-till management in the Great Plains have with turnover times ranging from hours to months (Folshown that increased cropping intensity increased soil organic carbon (SOC). The objectives of this study were to (i) determine which soil lett, 2001; Shaffer et al., ...

Rates of soil erosion in the dryland cropping region of Saskatchewan are investigated under alternative cropping strategies. Chemical fallow is examined as an alternative to tillage fallow for moisture and soil conservation. Conclusions include: (a) flexible cropping increases net discounted returns and substantially reduces soil erosion compared to the predominant crop rotation; (b) chemical f...

crops every 3 yr) and even continuous (annual) cropping in some instances. For example, annualized grain yields Water is the principle limiting factor in dryland cropping systems. for WCF are 75 to 100% greater than WF (Peterson et Surface soil physical properties influence infiltration and cropping al., 2000). Cropping intensification has been possible systems under no-till management may affe...