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131.
Wildlife subsistence hunting is a major source of protein for tropical rural populations and a prominent conservation issue. The intrinsic rate of natural increase. (rmax) of populations is a key reproductive parameter in the most used assessments of hunting sustainability. However, researchers face severe difficulties in obtaining reproductive data in the wild, so these assessments often rely on classic reproductive rates calculated mostly from studies of captive animals conducted 30 years ago. The result is a flaw in almost 50% of studies, which hampers management decision making. We conducted a 15‐year study in the Amazon in which we used reproductive data from the genitalia of 950 hunted female mammals. Genitalia were collected by local hunters. We examined tissue from these samples to estimate birthrates for wild populations of the 10 most hunted mammals. We compared our estimates with classic measures and considered the utility of the use of rmax in sustainability assessments. For woolly monkey (Lagothrix poeppigii) and tapir (Tapirus terrestris), wild birthrates were similar to those from captive populations, whereas birthrates for other ungulates and lowland‐paca (Cuniculus paca) were significantly lower than previous estimates. Conversely, for capuchin monkeys (Sapajus macrocephalus), agoutis (Dasyprocta sp.), and coatis (Nasua nasua), our calculated reproductive rates greatly exceeded often‐used values. Researchers could keep applying classic measures compatible with our estimates, but for other species previous estimates of rmax may not be appropriate. We suggest that data from local studies be used to set hunting quotas. Our maximum rates of population growth in the wild correlated with body weight, which suggests that our method is consistent and reliable. Integration of this method into community‐based wildlife management and the training of local hunters to record pregnancies in hunted animals could efficiently generate useful information of life histories of wild species and thus improve management of natural resources.  相似文献   
132.
Environmental Science and Pollution Research - Agriculture faces many challenges such as climate change, droughts, and salinity, which requires urgent interventions for fast adaptation and...  相似文献   
133.
Environmental Science and Pollution Research - Water quality is one of the most important indices for public health especially for drinking water consumptions. This study was conducted to survey...  相似文献   
134.
Environmental Science and Pollution Research - Electrocoagulation (EC) is one of the emerging technologies in groundwater and wastewater treatment as it combines the benefits of coagulation,...  相似文献   
135.
Environmental Science and Pollution Research - We reported the tin (II) tungstate nanoparticles as the photocatalyst and sensor modifier that were synthesized via chemical precipitation reaction...  相似文献   
136.
The chromium(VI) biosorption onto guava seeds, as an alternative method for Cr6+ removal from aqueous solutions, was investigated. The parameters affecting kinetics and equilibrium of Cr6+ adsorption onto guava seeds were studied. An external mass-transfer diffusion coefficient k and intra-particle diffusion coefficient ki were determined to measure the rate-limiting step of adsorption. A single external mass-transfer diffusion model and intra-particle diffusion models were used. The effects of initial pH, sorbent mass, and initial Cr6+ concentrations on mass-transfer coefficients were investigated. The external mass-transfer coefficient has an average value of 7.2×10-3 cm s-1, while the intra-particle mass-transfer diffusion coefficient was 0.34 mg g-1 min-0.5. This indicates that external diffusion to the guava seeds surface and intra-particle diffusion are both involved in the sorption process. The isotherm equilibrium data were well fitted by the Langmuir and Freundlich models with an average correlation coefficient R2=0.98. The maximum removal of Cr6+ was obtained at pH 1 (about 100% for adsorbent dose of 15 g l-1 and 25 mg l-1 initial concentration of Cr6+). The results indicated that the guava seeds exhibit acceptable sorption capacity.  相似文献   
137.
Highly activated carbon from the seed husk of Casuarina Casuarinas equisetifolia, a worldwide famous plant, have been prepared and tested for the removal of toxic Cr(VI) from its aqueous solution. The adsorbent was investigated for influences of initial chromium concentration (75, 100, 125, and 150 mg l-1), pH, contact time, and quantity of carbon on removal of Cr(VI) from aqueous solution at room temperature (25±2 °C). The adsorption kinetic of Cr(VI) was studied, and the rates of sorption were found to conform to pseudo-second-order kinetics with a good correlation (R2≥0.99). The Langmuir and Freundlich models fit the isotherm data well. Furthermore, the Gibbs free energy was obtained for each system and was found to be-5.29 kJ mol-1 for removal of Cr(IV). The negative value of Δ G° indicates the feasibility and spontaneous nature of adsorption. The results indicate that acidic pH (1.05) supported the adsorption of Cr(IV) on activated carbon. The maximum adsorption capacity of Cr(VI) on activated carbon was about 172.4 mg g-1 at pH 1.05.  相似文献   
138.
139.

The current discourse addresses fiscal issues, financial decentralization, and environmental quality and significantly affects economic development and sustainability. This investigation aims to address the research gap in fiscal decentralization and haze pollution for innovation and sustainable growth. This study uses the annual data of 270 Chinese cities from 2007 to 2016 for comprehensive analysis and employs spatial regression methods. The key findings imply that haze pollution in neighbouring cities causes further ecological issues. While the environmental regulations of China tend to have negative impacts on pollution, fiscal decentralization was found to be a key contributor to environmental pollution in Chinese cities. Overall, the study supports the validity of the pollution refuge hypothesis in China. Lastly, the conclusions allow us to conclude that China might need micro-level reforms regarding fiscal decentralization, environmental tax laws, and encouragement of cleaner production technologies.

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140.
Journal of Polymers and the Environment - In the context of sustainable development and natural products valorization, new ecological materials enter a logic aimed at removing the causes of...  相似文献   
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