This study was aimed to identify optimal indicators for microtopography-oriented soil quality assessment. Twenty-two soil physicochemical and biological parameters were investigated at 93 sampling points in five different microtopographic units in semiarid regions of the Loess Plateau, where the principal functions of eroded agriculture soils are related to productivity and anti-erosion ability...

As the world's population increases, marginal lands such as drylands are likely to become more important for food production. One proven strategy for improving crop production in drylands involves shifting from conventional tillage to no-till to increase water use efficiency, especially when this shift is coupled with more intensive crop rotations. Practices such as no-till that reduce soil dis...

Labile fractions of soil organic matter (SOM) respond rapidly to land management practices and can be used as a sensitive indicator of changes in SOM. However, there is little information about the effect of agroforestry practices on labile SOM fractions in semiarid regions of China. In order to test the effects of land use change from monocropping to agroforestry systems on labile SOM fraction...

The fungal loop model of semiarid ecosystems integrates microtopographic structures and pulse dynamics with key microbial processes. However limited data exist about the composition and structure of fungal communities in these ecosystems. The goal of this study was to characterize diversity and structure of soil fungal communities in a semiarid grassland. The effect of long-term nitrogen fertil...

Anthropogenic N deposition poses a threat to European Mediterranean ecosystems. We combined data from an extant N deposition gradient (4.3-7.3 kg N ha⁻¹ yr⁻¹) from semiarid areas of Spain and a field experiment in central Spain to evaluate N deposition effects on soil fertility, function and cyanobacteria community. Soil organic N did not increase along the extant gradient. Nitrogen fixation de...

The Columbia Basin of south-central Washington and north-central Oregon is a major potato-growing region in North America where more than 65,000 ha of potatoes are grown annually. The environment is semiarid (mean rainfall is between 15 and 22.5 cm), and the potato crop is irrigated mostly by center-pivot systems. Although the Columbia Basin is semiarid, potato production is annually threatened...

1. Definitions 1.1. Types of Aridity 1.2. Levels of Aridity 2. Paleoperspective 3. People and Land Use in Arid Lands 3.1. Foragers/Hunter–gatherers 3.2. Agriculturists 3.3. Pastoralists 4. Geomorphology of Arid and Semiarid Lands 5. Biological Diversity in Arid Lands 5.1. Arid and Semiarid Lands Plants and their Uses 5.2. The Future of the Conservation of Wild Plants in Arid Regions 6. Climatic...

BACKGROUND Biological soil crusts are common components of desert ecosystem; they cover ground surface and interact with topsoil that contribute to desertification control and degraded land restoration in arid and semiarid regions. METHODOLOGY/PRINCIPAL FINDINGS To distinguish the changes in topsoil affected by biological soil crusts, we compared topsoil properties across three types of succe...

In arid and semiarid areas, the effects of afforestation on soil organic carbon (SOC) have received considerable attention. In these areas, in fact, soil inorganic carbon (SIC), rather than SOC, is the dominant form of carbon, with a reservoir approximately 2-10 times larger than that of SOC. A subtle fluctuation of SIC pool can strongly alter the regional carbon budget. However, few studies ha...

Redistribution of soil, nutrients, and contaminants is often driven by wind erosion in semiarid shrublands. Wind erosion depends on wind velocity (particularly during episodic, high-velocity winds) and on vegetation, which is generally sparse and spatially heterogeneous in semiarid ecosystems. Further, the vegetation cover can be rapidly and greatly altered due to disturbances, particularly fir...