José Luis González Barrios

RADIAL GROWTH OF PECAN (Carya illinoinensis (Wangenh.) K. Koch) WOOD UNDERDIFFERENT WATER DEPTHS

Pecan (Carya illinoinensis (Wangenh.) K. Koch) has a genetic distinction due to the formation of annual growth rings, as a result of changes among environmental, management and genetic factors in the productivity of pecan. Such asseverations conducted to carry out the present study with the objective of describing the relationship between water availability corresponding to annual irrigation and annual wood growth (rings) using an image analyzer. Comments and analysis of these images allowed us to distinguish the extent of annual growth in relation to the irrigation. As a result, three groups were identified: wood growth with water stress (0.6mm), without water stress (2.3 to 2.7 mm) and with water excess (4.2 mm). Crecimiento radial... Guillermo González Cervantes et.al.

Impact of Land Use Changes in the Surface Hydrodynamics of a Water-harvesting Basin

Watershed management requires systematic measurements in order to reach good resources control. Some processes conditioning water transfers in the environment such as rain, run-off, infiltration, deep percolation, water uptake by plants, and evapotranspiration should be quantified to improve our knowledge of hydrological characterization and of the best management practices (Descroix/Nouvelot, 1997; Descroix et al., 2004). This work presents infiltration measurements and results produced with the Suction Disc Infiltrometer method realized in the Upper Nazas River Basin. This basin is the main water supply for Irrigation District 017 in northern Mexico, called the Lagunera region. Results show that soil surface controls the hydrodynamic behaviour of the watershed. Land use changes can be linked with productive practices that are causing strong hydrological consequences.

Integrated Water Management in Hydrological Basins:Multidisciplinary and Multi-Institutionality as an Action Paradigm

The variability in space and time of natural processes - especially the weather - together with market uncertainties and the globalization of the economy are factors that have led decision-makers to seek an integrated approach to facing the problems of water management and to integrating divergent interests. Such an approach offers the potential for balancing competing interests over water in hydrological basins (Sanchez et al., 2009). The wider definition of a basin includes policies, plans and activities used to control water and resources, as well as the human-induced processes that are associated with the basin. An integrated management approach has distinctive features as it seeks to balance institutional interests with those of the region and its stakeholders. It is a representative process that includes the research area and accounts for the opinions of all participants, in order to achieve an action plan that is accepted by the majority, thus reflecting a negotiated balance of interests. It also incorporates available scientific information in order to adequately understand hydrological as well as environmental factors that influence the condition of the basin. It also designs effective and participatory methods that involve all stakeholders in such a way as to distribute costs and benefits proportionally. As well as this, it constitutes a framework of agreements between different government offices, and within each office it guarantees the execution of the plans that were developed throughout the decision-making process, based on collective compromises, and conforming to the law. Finally, it also includes an ongoing basin management monitoring scheme with steps that can be easily measured.

Evapotranspiration in the Upper and Middle Nazas River Basins

Evapotranspiration, a combination of two simultaneous physical processes which account for the loss of water in vegetation-covered soils, through water evaporation from the moist soil-vegetation surface and control of transpiration through specialized plant tissues (stomata), is a fundamental hydrological variable at regional and basin levels for decision-making aimed at improving the water planning and management demanded by farming activities so as to maximize its usefulness, especially in arid and semi-arid zones where water resources are scarce or uncertain (Pereira et al., 2006; Dinpashoh, 2006; Jacobs et al., 2008). Also, evapotranspiration is an important time and space describer for climate regime classification, especially when related to precipitation. This variable is also a major soil-water balance component (Arora, 2002; Mundo/Martinez, 2002).