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Abstract:Reforestation has been widely adopted to restore soil fertility and ecosystem service function in the rocky desertification region of southwestern China. However, there has been limited research concerning the stoichiometry of carbon (C), nitrogen (N), and phosphorus (P) and nutrient resorption rate of plantations in karst ecosystems. In this study, we selected plantations of Pinus yunnanensis Franch. (PY) and Eucalyptus maideni F. Muell. (EM) in Yunnan Province. The C, N, and P concentrations and the C:N:P stoichiometry in different soil layers (0-10 cm, 10-20 cm, and 20-30 cm) were examined. The nutrient limitation and nutrient resorption efficiency were also analyzed. The leaf C and N concentrations in the PY plantation were higher than that in the EM plantation; the P concentration demonstrated the opposite trend, both in green and senesced leaves. Soil C, N, and P concentrations in the EM plantation were much greater than in the PY plantation at all three depths and decreased with the depth of the soil. In addition, the high ratios of C:P, N:P, C:Available P, and N:Available P in soil coupled with the ratios of N:P in leaves indicate that the EM plantation has a greater P deficiency than the PY plantation. In the EM plantation, the relatively low P concentrations in senesced leaves indicates efficient TP (Total phosphorus) resorption, which highlights that the high reuse proficiency of P could have favored moderating P limitation in the karst ecosystem. This research aids in understanding the stoichiometric characteristics that mediate forest properties, and provides a basis for management of vegetation in karst ecosystems.

In the past, iron-deficiency anemia in children has had a widespread presence in rural China. Given the recent economic growth in China, it is unclear if anemia among infants/toddlers remains a problem. The objective of this study is to measure the anemia rate in rural Chinese infants/toddlers across four major subpopulations and attempt to discover the sources of anemia. We use a mixed-methods approach combining quantitative data on 2909 rural Chinese infants/toddlers and their families with qualitative interviews with 84 caregivers of infants aged 6 to 30 months. Quantitative analysis indicates that the overall prevalence of anemia (43%) within sampled infants/toddlers was high, especially in comparison to the low rates of stunting (2–5%), being underweight (2%), and wasting (2–4%). These findings suggest that in rural China, anemia stems from the poor quality of the diets of infants/toddlers, rather than insufficient quantities of food being consumed. Qualitative analysis illustrates the factors that are contributing to anemia. Caregivers do not understand the causes of this condition, the symptoms that would lead one to recognize this condition, or the steps needed to treat their child with this condition. The findings offer a comprehensive understanding of the limited awareness of anemia among rural Chinese caregivers.

ObjectiveTo examine the correlation between birth season and early childhood development.BackgroundAlmost all previous studies that examine the effect of birth season on early childhood development were conducted in developed countries with a limited sample size. The present study was conducted in poor, rural areas of western China, a developing region with a continental monsoon climate.MethodWe administered a hemoglobin test to 650 infants (52% boys), aged 8–10 months, using a Hemocue Hb 201+ finger prick system, and assessed the cognitive and psychomotor development of sample infants using Bayley Scales of Infant Development.ResultsInfants born in winter have higher Hb concentrations (t = 3.63, p < 0.001) compared to infants born in summer. Similarly, cognitive development scores (t = 5.17, p < 0.001) and psychomotor development scores (t = 10.60, p < 0.001) were significantly higher among winter-born infants.ConclusionThe findings point to the involvement of birth season in early childhood development and suggest that aspects of the environment shape the experiences that contribute to early childhood development. Policy suggestions such as providing infants with ample opportunities for movement and stimulation during the cold season are discussed.

For schooling to play an important role in the development of human capital, the system of education needs to provide quality education, which among other things requires high‐quality teachers. Facing fiscal constraints and growing enrolments, school systems in developing countries often supplement their teaching staff by hiring contract teachers. However, there is limited evidence on how the effectiveness of these teachers compares to that of civil service teachers. We use a dataset from rural primary schools in western China to estimate the causal effect of contract teachers on student achievement and find that gains in student scores on standardised examinations in mathematics and Chinese are less in classes taught by contract teachers than in classes taught by civil service teachers. The results demonstrate that China's education system needs to focus on producing high‐quality teachers to improve the quality of schooling in its rural education system. The findings imply that educators in developing countries should not only seek to hire increasingly more civil service teachers in rural schools, but they should also identify ways of improving the quality of contract teachers. If efforts to improve teaching can succeed, rural students can learn more, earn higher incomes and contribute more to the productivity of the overall economy.