Desertification, which affects more than two-thirds of the world's arid and semi-arid regions, is a significant global ecological and environmental problem. There is a strong link between desertification of the drylands and emission of CO₂ from soil and vegetation to the atmosphere. The Horqin Sandy Land is a severely desertified area in China's agro-pastoral ecotone due to its fragile ecology, combined with unsustainable land management.

An assessment of sensitivity to land degradation has been carried out in the Extremadura region, SW Spain, by means of a modelling approach developed by the European Commission funded MEDALUS project (Mediterranean Desertification and Land Use) which identifies such areas on the basis of an index (Environmentally Sensitive Area index, ESA index) that incorporates data on environmental quality (climate, vegetation, soil) as well as anthropogenic factors (management).

Land use and land cover changes in the Brazilian Amazon have major implications for regional and global carbon (C) cycling. Cattle pasture represents the largest single use (about 70%) of this once-forested land in most of the region. The main objective of this study was to evaluate the accuracy of the RothC and Century models at estimating soil organic C (SOC) changes under forest-to-pasture conditions in the Brazilian Amazon. We used data from 11 site-specific 'forest to pasture' chronosequences with the Century Ecosystem Model (Century 4.0) and the Rothamsted C Model (RothC 26.3).

PURPOSE: Many Mediterranean drylands are characterized by strong erosion in headwater catchments, where connectivity processes play an important role in the redistribution of water and sediments. Sediment connectivity describes the ease with which sediment can move through a catchment. The spatial and temporal characterization of connectivity patterns in a catchment enables the estimation of sediment contribution and transfer paths. Apart from topography, vegetation cover is one of the main factors driving sediment connectivity.

BACKGROUND AND AIMS: Stoichiometric relations drive powerful constraints on many ecosystem processes. However, our understanding of the hierarchical responses of plant C:N:P stoichiometry at different levels of biological organization to global change factors remains limited. METHODS: we examined the plant C:N:P stoichiometric responses to N deposition and mowing (hay making) at both species- and community-level by carrying out a 4-year field experiment in the temperate steppe of northern China.

1. Little is known about the diversity and land management response of native solitary bees in globally rare barrens restricted to the northeastern United States. Herein we assess solitary bee diversity in a scrub oak barrens 2 years after a mow and herbicide treatment. 2. Standard bowl‐trap and sweep‐net surveys were repeated six times during June–August in four treated scrub oak patches and a nearby untreated scrub oak patch. 3. Bee richness and total abundance (all specimens) did not differ appreciably between the treated and untreated scrub oak.

The composition and structure of bacterial communities were examined in soil subjected to a range of diverse agricultural land management and crop production practices. Length heterogeneity polymerase chain reaction (LH-PCR) of bacterial DNA extracted from soil was used to generate amplicon profiles that were analyzed with univariate and multivariate statistical methods. Five land management programs were initiated in July 2000: conventional, organic, continuous removal of vegetation (disk fallow), undisturbed (weed fallow), and bahiagrass pasture (Paspalum notatum var Argentine).

The present e-collection of scientific works deals with results of research on issues of economy, agrarian and engineering sciences studied by researchers, post-graduate students, magisters and students of Mykolayiv State Agrarian Univ. and other educational establishments of the Ministry of Agrarian Policy of Ukraine are elucidated. The issue comprises 30 scientific papers, distributed by three sections, in particular Economic sciences (18 papers), Agricultural sciences (10) and Engineering sciences (2 papers), and, what is important, except the Ukrainian-language contents (pp.

Soil erosion and subsequent degradation has been a contributor to societal collapse in the past and is one of the major expressions of desertification in arid regions. The revised universal soil loss equation (RUSLE) models soil lost to water erosion as a function of climate erosivity (the degree to which rainfall can result in erosion), topography, soil erodibility, and land use/management.

Highly managed biotic systems, such as agricultural crops and managed turf, often require multiple applications of pesticides that may be transported with runoff to areas beyond the intended target site. Pesticides have been detected in surface waters of rural and urban watersheds raising questions concerning their source, potential environmental effects and a need for strategies to reduce their inputs.

Ecosystem level processes and species interactions have become important concepts in conservation and land management. Despite being New Zealand’s greatest contributors to global diversity, native invertebrates have been largely overlooked in the assessment of land values, and their diversity has often been assumed to reflect native plant diversity without justification. Invertebrates can in fact affect plant species composition, and in ecosystems such as New Zealand’s remaining indigenous and semi-modified tussock grasslands can do so in excess of more conspicuous vertebrate grazers.

The excessive use of plant protection products (PPPs) has given rise to issues of public and environmental health because of their toxicity. Reducing the use of toxic PPPs and replacing them with products that are less toxic for human health and the environment have become socially, environmentally and economically indispensable.