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101.
There has been a lengthy debate on whether the abundance of adult reef fishes depends on prerecruitment or postrecruitment processes; however, we still do not have the ability to predict the magnitude of local fish recruitment. Here we show that the success of the leopard grouper (Mycteroperca rosacea) recruitment in the Gulf of California, Mexico, is determined by the availability of nursery habitat, which in turn is strongly correlated to climate conditions. Observational and experimental studies showed that leopard grouper larvae recruit preferentially on shallow rocky bottoms with brown algal (Sargassum spp.) beds, and that abundance of recruits is determined by the availability of Sargassum. The biomass of Sargassum decreases linearly with an increase in the Multivariate El Ni?o Southern Oscillation (ENSO) Index (MEI; an index positively correlated with water temperature and negatively correlated with nutrient availability). We analyzed the relationship between the interannual variation of MEI and the recruitment of the leopard grouper using field estimates of abundance of juvenile groupers. Our results show that there is a nonlinear relationship between recruitment and the oceanographic climate, in that the density of recruits decreases exponentially with increasing MEI. The predictability of leopard grouper recruitment has important implications for fisheries management, since it could allow adaptive management without expensive stock assessment programs.  相似文献   
102.
The pyramid of human needs developed by Abraham Maslow is based upon the presumption that until a person's lower level needs are fulfilled, higher level needs remain irrelevant. Groundwater and land-use management can likewise utilize such a hierarchy in integrating plans and operations with the needs of the society. Only once a region's population has fulfilled more basic concerns can higher-level groundwater and land-use management needs be effectively achieved. Attaining the ultimate goal of resource sustainability would certainly require considerable public backing, both for financial support and minimizing ambient pollution. For efficient water management to supply a society's water needs for future generations, sustainable groundwater management will require the full support of an educated society. The objective of the authors is to point out how essential it is to integrate operational strategies into regional hierarchies of needs applicable to groundwater management, land-use, and social planning. The situation of groundwater resources in Israel's Sharon Coastal aquifer region is taken as a case in point. Remedial groundwater activities have been undertaken in the management program for this aquifer. But it appears that maximal management efficiency cannot be achieved until the public's basic concerns are satisfactorily addressed and water resources planners reach consensus and a working partnership with the society in question. Operational measures must be clearly shown to benefit the region's population as regards their social, economic, and environmental concerns. This can only be achieved through public education, promoting awareness of the issuesbreak involved.  相似文献   
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Environmental Science and Pollution Research - Antibiotic resistance genes (ARGs) and antimicrobial resistance elements (AMR) are novel environmental contaminants that pose a significant risk to...  相似文献   
105.
Regional Environmental Change - Local perspectives on changing weather and climate and analyses of meteorological data represent two different but potentially complementary ways of knowing about...  相似文献   
106.
Environmental Science and Pollution Research - The heterogeneous catalytic degradation of a model azo dye, acid red 1 (AR1), initiated by zero valent iron nanoparticles (ZVINP), and its synergic...  相似文献   
107.
A study of 6350 consecutive transvaginal ultrasound examinations was performed as part of a routine fetal evaluation. Twenty-one cases (0.33 per cent) of early second-trimester sonographic detection of minor renal abnormalities (unilateral renal agenesis, pelvic kidney, and double collecting system) are presented. The sonographic diagnosis was made at 14–18 weeks of pregnancy and confirmed, in all of the 21 fetuses, postnatally or by post-mortem. A high incidence of associated fetal anomalies (24 per cent) and parental renal abnormalities (14 per cent) was demonstrated. Transvaginal sonography was found to be a useful tool for diagnosing these renal anomalies as early as 14 weeks of pregnancy. The likelihood of various associated anomalies and long-term implications on renal function raise questions concerning the prenatal management of such patients.  相似文献   
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When utilized with a stochastic source of surface water for irrigation, groundwater may serve to mitigate fluctuations in the supply of water. The benefit corresponding to this service is the buffer value of groundwater. We show that the buffer value is positive. Numerical studies reveal that its magnitude can be significant. The paper also offers a characterization of groundwater extraction in such a setting.  相似文献   
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