Question: We present a general structural carbon nutrient balance hypothesis parallel to Bryant et al.’s defensive chemistry hypothesis. Our hypothesis suggests that because herb species require a lower investment of carbon per unit length of stem than do woody plants, herbs should be at a competitive advantage where the leaf area of plants in the ground layer is limited by light (or fixed carb...

Jack A. Morgan is plant physiologist and Feike Dijkstra is post-doc research ecologist at the Rangeland Resources Research Unit, Ronald F. Follett is research leader and soil scientist and Stephen Del Grosso is a soil scientist and ecologist at the Soil Plant Nutrient Research Unit, USDA Agricultural Research Service Northern Plains Area, Fort Collins, Colorado. Leon Hartwell Allen Jr. is soil ...

Arbuscular mycorrhizal fungi (AMF) are critical links in plant-soil continuum and play a critical role in soil carbon cycles. Soil respiration, one of the largest carbon fluxes in global carbon cycle, is sensitive to precipitation change in semiarid ecosystems. In this study, a field experiment with fungicide application and water addition was conducted during 2010-2013 in a semiarid steppe in ...

A bioassay arena was developed to test the response of the Japanese beetle, Popillia japonica Newman (Coleoptera: Scarabaeidae), to various plant-derived factors that may influence the selection of oviposition sites. In choice experiments with natural and artificial plant cues, females preferred to lay eggs in ryegrass rather than in artificial resources. Artificial grass stems received more eg...

It is important to indicate at the outset that I do not intend to argue for more funding for soil conservation programs, but rather for more efficient use of the resources presently committed. Before we can go very far in evaluating the impacts of soil conservation spending changes, we need additional background on soil conservation programs. It is hoped that such information will tell us somet...

Soil erosion forms a major threat to European soil resources. Although soil is a vital and largely non-renewable resource, it has not been the subject of comprehensive EU action so far. A thematic strategy for soil protection, which recognises soil erosion as one of the major threats, has currently been placed high on Europe’s political Agenda. Assessing and monitoring soil erosion is needed to...

Executive Summary Soil quality is an account of the soil's ability to provide ecosystem and social services through its capacities to perform its functions under changing conditions (after Tóth et al. 2007.) The concept of soil quality expressed by this definition allows practical applications with regards to targeted social and/or ecosystem services, including agri-environmental services. The ...

If all resources are harnessed, and adequate measures taken to minimize soil degradation, sufficient food to feed the population in 2020 can be produced, and probably sufficient for a few billion more. These were the key conclusions from a Discussion Meeting held at the Royal Society in London in December 1996. The meeting entitled ‘Land resources: on the edge of the Malthusian precipice?’ atte...

At present, such research is still very rare in soil science literature. Soils typically exhibit complex spatial variation of multi-categorical For characterizing the spatial correlation of categorivariables such as soil types and soil textural classes. Quantifying and cal variables in geosciences, the main descriptive tools assessing soil spatial variation is necessary for land management and ...

There is currently much interest in the interactions between exotic plants and soil organisms. Exotic invasive species can have profound effects on the microbial community of the soil and positive feedback of soil biota to invasive plants may facilitate their successful invasion. To better understand the impacts of Ambrosia artemisiifolia L. invasion on microbial carbon source utilization and r...